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Gynecology_Novak. 74. Ahmed I, Nazir R, Chaudhary MY, et al. Triple assessment of breast lump. J Coll Physician Surg 2007;17:535–538. 75. Ciatto S, Houssami N. Breast imaging and needle biopsy in women with clinically evident breast cancer: does combined imaging change overall diagnostic sensitivity? Breast 2007;16:382–386. 76. Vimpeli SM, Saarenmaa I, Huhtula H, et al. Large-core needle biopsy versus fine needle aspiration biopsy in solid breast lesions: comparison of cost and diagnostic value. Acta Radiol 2008;49:863– 869. 77. Kuo YL, Chang TW. Can concurrent core biopsy and fine needle aspiration biopsy improve the false negative rate of sonographically detectable breast lesions? BMC Cancer 2010;10:371–377. 78. Ellis I, Humphreys M, Michell M, et al. Best Practice No. 179: guidelines for breast needle core biopsy handling and reporting in breast screening assessment. J Clin Pathol 2005;57:897–902. 79.


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Gynecology_Novak. Ellis I, Humphreys M, Michell M, et al. Best Practice No. 179: guidelines for breast needle core biopsy handling and reporting in breast screening assessment. J Clin Pathol 2005;57:897–902. 79. Blaylock RC, Byrne JLB, Clayton F, et al. The Internet pathology laboratory for medical education. Available online at: http://202.193.198.50/glblnet/severbj1/bl/WEBPATH.HTM 80. Ciampa A, Xu B, Bayiee D, et al. HER-2 status in breast cancer; correlation of gene amplification by FISH with immunohistochemistry expression using advanced cellular imaging system. Appl Immunohistochem Mol Morphol 2006;14:132–137. 81. Vaugh A, Crowe JP. Mammary ductoscopy and ductal washings for the evaluation of patients with pathologic nipple discharge. Breast 2009;15:254–260. 82. Courtillot C, Plu-Bureau, Binart N, et al. Benign breast diseases. J Mammary Gland Bio Neoplasia 2005;10:325–335. 83. Santen RJ, Mansel R. Benign breast disorder. N Engl J Med 2005;353:275–285. 84.


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Gynecology_Novak. 83. Santen RJ, Mansel R. Benign breast disorder. N Engl J Med 2005;353:275–285. 84. Berg Wa, Sechin AG, Marques H, et al. Cystic breast masses and the ACRIN 6666 experience. Radiol Clin North Am 2010;48:931– 987. 85. Schindler AE. Non-contraceptive benefits of hormonal contraceptives. Minerva Ginecol 2010;62:319–329. 86. Iwanitsu Y, Shimoda K, Abe H, et al. Anxiety, emotional suppression, and psychological distress before and after breast cancer diagnosis. Psychosomatics 2005;46:19–24. 87. Mannello F, Tonti GA, Papa S. Human gross cyst breast disease and cystic ﬂuid: bio-molecular, morphological and clinical studies. Breast Cancer Res Treat 2006;97:115–129. 88. Radowicki S, Kunicki M, Bandurska-Stankiewicz E. Prostate-specific antigen in the serum of women with benign breast disease. Eur J Obstet Gynecol Reprod Bio 2008;138:212–216. 89. Katz VL, Lentz G, Lobo RA, et al. Comprehensive gynecology: fibrocystic changes. Philadelphia, PA: Mosby, 2007. 90.


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Gynecology_Novak. 89. Katz VL, Lentz G, Lobo RA, et al. Comprehensive gynecology: fibrocystic changes. Philadelphia, PA: Mosby, 2007. 90. Daly CP, Bailey JE, Klein KA, et al. Complicated breast cyst on sonography: is aspiration necessary to exclude malignancy? Acad Radiol 2008;15:610–617. 91. Vargas H, Vargas M, Gonzalez KD, et al. Outcomes of sonographybased management of breast cysts. Am J Surg 2004;188:443–447. 92. Kabat GC, Jones JG, Olson N, et al. A multi-center prospective cohort study of benign breast and risk of subsequent breast cancer. Cancer Causes Control 2010;26:82–826. 93. Fitzgibbons P, Henson DE, Hutter RV, et al. Benign breast changes and the risk of subsequent breast cancer: an update of the 1985 consensus statement. Arch Pathol Lab Med 1998;122:1053–1055. 94. Chun J, El-Tamer M, Joseph KA, et al. Predictors of breast cancer development in a high-risk population. Am J Surg 2006;192:474– 477. 95.


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Gynecology_Novak. 94. Chun J, El-Tamer M, Joseph KA, et al. Predictors of breast cancer development in a high-risk population. Am J Surg 2006;192:474– 477. 95. Page D, Dupont WD. Anatomic markers of human premalignancy and risk of breast cancer. Cancer 1990;66:1326–1335. 96. Hartmann LC, Sellers TA, Frost MN, et al. Benign breast disease and the risk of breast cancer. N Engl J Med 2005;352:229–237. 97. Worsham MJ, Raju U, Lu M, et al. Risk factors for breast cancer from benign breast diseases in a diverse population. Breast Cancer Res Treat 2009;118:1–7. 98. Webb Pm, Bryne C, Schnitt SJ, et al. A prospective study of diet and benign breast disease. Cancer Epidemiol Biomarkers Prev 2004;13:1106–1113. 99. Ishitani K, Lin T, Manson JE, et al. Caffeine consumption and risk of breast cancer in a large cohort of women. Arch Intern Med 2008;168:2022–2031. 100.


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Gynecology_Novak. 99. Ishitani K, Lin T, Manson JE, et al. Caffeine consumption and risk of breast cancer in a large cohort of women. Arch Intern Med 2008;168:2022–2031. 100. Ganmaa D, Willett W, Fiskanich D, et al. Coffee, tea, caffeine and risk breast cancer: a 22-year follow-up. Int J Cancer 2008;122:2071– 2076. 101. Holmes MD, Willett WC. Does diet affect breast cancer risk? Breast Cancer Res 2004;6:170–178. 102. Parsay S, Olfati F, Nahidi S, et al. Therapeutic effects of vitamin E on cyclic mastalgia. Breast J 2009;15:510–514. 103. Kashanian M, Manzinami R, Jalalmanesh S. Pyridoxine (vitamin B6) therapy for premenstrual syndrome. Int J Gynaecol Obstet 2007;96:43–44. 104. Pruthis S, Wahner-Roedler DL, Torkelson CJ, et al. Vitamin E and evening primrose oil for management of cyclical mastalgia: a randomized pilot study. Altern Med Rev 2010;15:59–67. 105. Smallwood J, A-Kye D, Taylor I. Vitamin B6 in the treatment of premenstrual mastalgia. Br J Clin Pract 1986;40:532–533. 106.


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Gynecology_Novak. 105. Smallwood J, A-Kye D, Taylor I. Vitamin B6 in the treatment of premenstrual mastalgia. Br J Clin Pract 1986;40:532–533. 106. Ernster V, Goodson W 3rd, Hunt T, et al. Vitamin E and benign breast “disease”: a double-blind, randomized clinical trial. Surgery 1985;97:490–494. 107. Horner N, Lampe J. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368–1380. 108. Kaviani A, Mehrdad N, NajafiM, et al. Comparison of naproxen with placebo for the management of noncyclical breast pain: a randomized, double blind, controlled trial. World J Surg 2008;32:2464– 2470. 109. Bundred NJ. Breast pain. Clin Evid (Online). 2007;2007:pii0812. 110. Ramakrishnan R, Werbeck J, Khurana K, et al. Expression of interleukin-6, and tumor necrosis factor a and histopathologic findings in painful and nonpainful breast tissue. Breast J 2003;9:91–97. 111.


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Gynecology_Novak. 111. Ford O, Lethaby A, Roberts H, et al. Progesterone for premenstrual syndrome. Cochrane Database Syst Rev 2009;2:CD003415. 112. Olawaiye A, Withiam-Leitch M, Danakas G, et al. Mastalgia: a review of management. Reprod Med 2005;50:933–939. 113. Hadi M. Sports brassiere: is it a solution for mastalgia? Breast J 2000;6:407–409. 114. Eberl MM, Phillips RL Jr, Lamberts H, et al. Characterizing breast symptoms in family practice. Ann Fam Med 2008;6:528–533. 115. Browne M. Prevalence and impact of cyclic mastalgia in a United Stated clinic-based sample. Am J Obstet Gynecol 1997;177:126–132. 116. Smith R, Pruthi S, Fitzpatrick L. Evaluation and management of breast pain. Mayo Clin Proc 2004;79:353–372. 117. Rosolowich V, Saettler E, Szuck B, et al. Mastalgia. Society of Obstetricians and Gynecologists of Canada (SOGC). J Obstet Gynaecol Can 2006;28:49–71. 118.


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Gynecology_Novak. 117. Rosolowich V, Saettler E, Szuck B, et al. Mastalgia. Society of Obstetricians and Gynecologists of Canada (SOGC). J Obstet Gynaecol Can 2006;28:49–71. 118. DennersteinL,LehertP,B¨ackstr¨omTC,HeinemannK. Premenstrual symptoms—severity, duration and typology: an international cross-sectional study. Menopause Int 2009;15:120–126. 119. Davies E, Gateley C, Miers M, et al. The long-term course of mastalgia. J R Soc Med 1998;91:462–464. 120. Gumm R, Cunnick GH, Mokbel K. Evidence for the management of mastalgia [review]. Curr Med Res Opin 2004;20:681–684. 121. Ort´-Mendoza CM, Lucas Flores MA, et al. Mastalgia treatment with tamoxifen. Ginecol Obstet Mex 2003;71:502–507. 122. Ortiz-Mendoza CM, Olvera-Mancilla M. Danazol effectivity in control of moderate to severe mastalgia. Cir Cir 2004;72:479–482. 150. Alkhunaizi AM, Ismail A, Yousif BM. Breast fibroadenomas in renal transplant recipients. Transplant Proc 2004;36:1839–1840. 151.


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Gynecology_Novak. 150. Alkhunaizi AM, Ismail A, Yousif BM. Breast fibroadenomas in renal transplant recipients. Transplant Proc 2004;36:1839–1840. 151. Seo YL, Choi CS, Yoon DY, et al. Benign breast diseases associated with cyclosporine therapy in renal transplant recipients. Transplant Proc 2005;37:4315–4319. 152. Darwish A, Nasr AO, El Hassan LA, et al. Cyclosporine— a therapy-induced multiple bilateral breast and accessory axillary breast fibroadenomas: a case report. J Med Case Rep 2010;4:267. 153. Jayasinghe Y, Simmons PS. Fibroadenomas in adolescence. Curr Opin Obstet Gynecol 2009;21:402–406. 154. Tse GM, Niu Y, Shi HJ. Phyllodes tumor of the breast: an update. Breast Cancer 2010;17:29–34. 155. Guerrero M, Ballard B, Grau A. Malignant phyllodes tumor of the breast: review of the literature and case report of stromal overgrowth. Surg Oncol 2003;12:27–37. 156.


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Gynecology_Novak. 155. Guerrero M, Ballard B, Grau A. Malignant phyllodes tumor of the breast: review of the literature and case report of stromal overgrowth. Surg Oncol 2003;12:27–37. 156. Chen WH, Cheng Sp, Tzen Cy, et al. Surgical treatment of phyllodes tumors of the breast: retrospective review of 172 cases. J Surg Oncol 2005;91:185–194. 157. Zurrida S, Bartoli C, Galimberti V, et al. Which therapy for unexpected phyllode tumour of the breast? Eur J Cancer 1992;28:654– 657. 158. Karim RZ, Gerega SK, Ynag YH, et al. Phyllodes tumor of the breast: a clinicopathological analysis of 65 cases from a single institution. Breast 2009;18:165–170. 159. Grabrowski J, Salztein SL, Sadler GR, et al. Malignant phyllodes tumors: a review of 752 cases. Am Surg 2007;73:967–969. 160. Ben Hassouna J, Damak T, Gamoudi A, et al. Phyllodes tumors of the breast: a case series of 106 patients. Am J Surg 2006;192:141– 147. 161.


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Gynecology_Novak. 160. Ben Hassouna J, Damak T, Gamoudi A, et al. Phyllodes tumors of the breast: a case series of 106 patients. Am J Surg 2006;192:141– 147. 161. Belkacemi Y, Bousquet G, Marsiglia H, et al. Phyllodes tumor of the breast. Int J Radiat Oncol Biol Phys 2008;70:492–500. 162. Barrio AV, Clark BD, Goldberg JI, et al. Clinicopathologic features and long-term outcomes of 292 phyllodes tumors of the breast. Ann Surg Oncol 2007;14:2961–2970. 163. Chao T-C, Lo Y-F, Chen M-F. Phyllodes tumors of the breast. Eur Radiol 2003;13:88–93. 164. Kurt A, Tatlidede S, Sade C, et al. A giant cystosarcoma phyllodes. Breast J 2004;10:546–547. 165. Foxcroft LM, Evans EB, Porter AJ. Difficulties in the pre-operative diagnosis of phyllodes tumors of the breast: a study of 84 cases. Breast 2007;16:27–37. 166. Franceschini G, Masetti R, Brescia A, et al. Phyllodes tumor of the breast: magnetic resonance imaging findings and surgical treatment. Breast J 2005;11:44–45. 167.


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Gynecology_Novak. 166. Franceschini G, Masetti R, Brescia A, et al. Phyllodes tumor of the breast: magnetic resonance imaging findings and surgical treatment. Breast J 2005;11:44–45. 167. Kraemer B, Hoffmann J, Roehm C, et al. Cystosarcoma of the breast: a rare diagnosis: case studies and review of literature. Arch Gynecol Obstet 2007;276:649–653. 168. Giri D. Recurrent challenges in the evaluation of fibroepithelial lesions. Arch Pathol Lab Med 2009;133:713–721. 169. Bode MK, Rissanen T, Apaja-Sarkkinen M. Ultrasonography and core needle biopsy in the differential diagnosis of fibroadenoma and phyllodes tumor. Acta Radiol 2007;48:708–713. 170. Tomimaru Y, Komoike Y, Egawa C, et al. A case of phyllodes tumor of the breast with a lesion mimicking fibroadenoma. Breast Cancer 2005;12:322–326. 171. Roa JC, Tapia O, Carrasco P, et al. Prognostic factors of phyllodes tumor of the breast. Pathol Int 2006;56:309–314. 172.


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Gynecology_Novak. 171. Roa JC, Tapia O, Carrasco P, et al. Prognostic factors of phyllodes tumor of the breast. Pathol Int 2006;56:309–314. 172. Macdonald OK, Lee CM, Tward JD, et al. Malignant phyllodes tumor of the female breast: association of primary therapy with cause-specific survival from the Surveillance, Epidemiology, and End Results (SEER) program. Cancer 2006;107:2127–2133. 173. Cheng SP, Chang YC, Liu TP, et al. Phyllodes tumor of the breast: the challenge persists. World J Surg 2006;30:1414–1421. 174. Asoglu O, Ugurlu MM, Blanchard K, et al. Risk factors for recurrence and death after primary surgical treatment of malignant phyllodes tumors. Ann Surg Oncol 2004;11:1011–1017. 175. Barth RJ Jr, Wells WA, Mitchell SE, et al. A prospective, multi-institutional study of adjuvant radiotherapy after resection of malignant phyllodes tumors. Ann Surg Oncol 2009;16:2288–2294. 176.


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Gynecology_Novak. Barth RJ Jr, Wells WA, Mitchell SE, et al. A prospective, multi-institutional study of adjuvant radiotherapy after resection of malignant phyllodes tumors. Ann Surg Oncol 2009;16:2288–2294. 176. Goksel H, Yagmurdur M, Demirhan B, et al. Management strategies for patients with nipple discharge. Langenbecks Arch Surg 2005;390:52–58. 177. Montroni I, Santini D, Zucchini G, et al. Nipple discharge: is its significance as a risk factor for breast cancer fully understood? Observational study including 915 consecutive patients who underwent selective duct excision. Breast Cancer Res Treat 2010;123:895– 900. 178. Lang JE, Kuerer HM. Breast ductal secretions: clinical features, potential uses, and possible applications. Cancer Control 2007;14:350–359. 179. Alcock C, Layer GT. Predicting occult malignancy in nipple discharge. ANZ J Surg 2010;80:646–649. 180. Hussain AN, Policarpio C, Vincent MT. Evaluating nipple discharge. Obstet Gynecol Surv 2006;61:278–283. 181.


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Gynecology_Novak. 180. Hussain AN, Policarpio C, Vincent MT. Evaluating nipple discharge. Obstet Gynecol Surv 2006;61:278–283. 181. Morrogh M, Park A, Elkin EB, et al. Lessons learned from 416 cases of nipple discharge of the breast. Am J Surg. 2010;200:73–80. 182. Ling H, Liu GY, Lu JS, et al. Fiberoptic ductoscopy-guided intraductal biopsy improve the diagnosis of nipple discharge. Breast J 2009;15:168–175. 183. Dooley W, Francescatti D, Clark L, et al. Office-based breast ductoscopy for diagnosis. Am J Surg 2004;188:415–418. 184. Beechy-Newman N, Kulkarni D, Kothari A, et al. Throwing light on nipple discharge. Breast J 2005;11:138–139. 185. Wahner-Roedler D, Reynolds C, Morton M. Spontaneous unilateral nipple discharge: when screening tests are negative—a case report and review of current diagnostic management of a pathologic nipple discharge. Breast J 2003;9:49–52. 186.


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Gynecology_Novak. 186. Mandal S, Jain S. Purulent nipple discharge—a presenting manifestation in tuberculous mastitis. Breast J 2007;13:205. 187. El Idrissi F, Fadii A. Erosive adenomatosis of the nipple. J Gynecol Obstet Biol Reprod 2005;34:813–814. 188. Ku BS, Kwon OE, Kim DC, et al. A case of erosive adenomatosis of nipple treated with total excision using purse-string suture. Dermatol Surg 2006;32:1093–1096. 189. Haj M, Loberant N, Salamon V, et al. Membranous fat necrosis of the breast: diagnosis by minimally invasive technique. Breast J 2004;10:504–508. 190. Tan PH, Lai LM, Carrington EV, et al. Fat necrosis of the breast—a review. Breast 2006;15:313–318. 191. Dener C, Inan A. Breast abscesses in lactating women. World J Surg 2003;27:130–133. 192. Moazzez A, Kelso RL, Towfigh S, et al. Breast abscess bacteriologic features in the era of community-acquired methicillin-resistant Staphylococcus aureus epidemics. Arch Surg 2007;142:881–884. 193.


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Gynecology_Novak. Moazzez A, Kelso RL, Towfigh S, et al. Breast abscess bacteriologic features in the era of community-acquired methicillin-resistant Staphylococcus aureus epidemics. Arch Surg 2007;142:881–884. 193. Rizzo M, Gabram S. Management of breast abscesses in nonlactating women. Am Surg 2010;76:292–295. 194. Berna-Serna J, Madrigal M, Berna-Serna J. Percutaneous management of breast abscesses: an experience of 39 cases. Ultrasound Med Biol 2004;30:1–6. 195. Christensen AF, Al-Suliman, Nielsen KR, et al. Ultrasound-guided drainage of breast abscess: results in 151 patients. Br J Radiol 2005;78:186–188. 196. Dabbas N, Chand M, Pallett A, et al. Have the organisms that cause breast abscess changed with time? Implications for appropriate antibiotic usage in primary and secondary care. Breast J 2010;16:412–415. 197. Bharat A, Gao F, Aft RL, et al. Predictors of primary breast abscesses and recurrence. World J Surg 2009;33:2582–2586. 198.


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Gynecology_Novak. 197. Bharat A, Gao F, Aft RL, et al. Predictors of primary breast abscesses and recurrence. World J Surg 2009;33:2582–2586. 198. Li S, Grant C, Degnim A, et al. Surgical management of recurrent subareolar breast abscesses: Mayo clinical experience. Am J Surg 2006;192:528–529. 199. Lannin D. Twenty-two-year experience with recurring subareolar abscess and lactiferous duct fistula treated by a single breast surgeon. Am J Surg 2004;188:407–410. 200. Versluijs-Ossewaarde F, Roumen R, Goris R. Subareolar breast abscesses: characteristics and results of surgical treatment. Breast J 2005;11:179–182. 201. Gorczyca DP, Gorczyca SM, Gorczyca KL. The diagnosis of silicone breast implant rupture. Plast Reconstr Surg 2007;120:49–61. 202. Tanne J. FDA approves silicone implants 14 years after their withdrawal. BMJ 2006;333:1139. 203.


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Gynecology_Novak. 202. Tanne J. FDA approves silicone implants 14 years after their withdrawal. BMJ 2006;333:1139. 203. Chung K, Greenfield ML, Walters M. Decision-analysis methodology in the work-up of women with suspected silicone breast implant rupture. Plast Reconstr Surg 1998;102:689–695. 204. Lipworth L, Tarone RE, McLaughlin JK. Silicone breast implants and connective tissue disease: an updated review of the epidemiologic evidence. Ann Plast Surg 2004;52:598–601. 205. Fryzek JP, Holmich L, McLaughlin JK, et al. A nationwide study of connective tissue disease and other rheumatic conditions among Danish women with long-term cosmetic breast implantation. Ann Epidemiol 2007;17:374–379. 206. Janowsky E, Lawrence L, Hulka BS. Meta-analyses of relationship between silicone breast implants and the risk of connective-tissue diseases. N Engl J Med 2000;342:781–790. 207.


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Gynecology_Novak. 206. Janowsky E, Lawrence L, Hulka BS. Meta-analyses of relationship between silicone breast implants and the risk of connective-tissue diseases. N Engl J Med 2000;342:781–790. 207. Holmich LR, Lipworth L, McLaughlin JK, et al. Breast implant rupture and connective tissue disease: a review of the literature. Plast Reconstr Surg 2007;120:62–69. 208. Bar-Meir E, Eherenfeld M, Shoenfeld Y. Silicone gel breast implants and connective tissue disease—a comprehensive review. Autoimmunity 2003;36:193–197. 209. McLaughlin JK, Lipworth L, Murphy DK, et al. The safety of silicone gel-filled breast implants: a review of the epidemiologic evidence. Ann Plastic Surg 2007;59:569–580. 210. Lipworth L, Tarone R, McLaughlin J. Silicone breast implants and connective tissue disease: an update review of the epidemiologic evidence. Ann Plast Surg 2004;52:598–601. 211.


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Gynecology_Novak. 210. Lipworth L, Tarone R, McLaughlin J. Silicone breast implants and connective tissue disease: an update review of the epidemiologic evidence. Ann Plast Surg 2004;52:598–601. 211. Breiting V, Holmich L, Brandt B, et al. Long-term health status of Danish women with silicone breast implants. Plast Reconstr Surg 2004;114:217–226. 212. Friis S, Holmich LR, McLaughlin JK, et al. Cancer risk among Danish women with cosmetic breast implants. Int J Cancer 2006;118:998–1003. Daniel L. Clarke-Pearson Emily Ko Lisa Abaid Kevin Schuler The preoperative evaluation should be complete and thorough, taking into account the essential aspects of the patient’s general medical condition and prior surgical history. The risks, benefits, and potential complications of the surgical procedure should be discussed with the patient, including the most frequent complications of the particular surgical procedure. Alternative management, if any, should be presented.


Gynecology_Novak

Gynecology_Novak. A calculated body mass index (BMI) can be used as a surrogate marker for nutritional status. Careful and meticulous ﬂuid and electrolyte management is essential for all patients undergoing major surgical procedures. Although satisfactory analgesia is easily achievable with available methods, patients continue to suffer unnecessarily from postoperative pain. Prophylactic antibiotics should be employed judiciously. Prompt identification of perioperative infections and their specific treatments are critical to minimize the impact of this common morbidity. Early in the clinical course, a postoperative small bowel obstruction may exhibit signs and symptoms identical to those of ileus. Initial conservative management as outlined for the treatment of ileus is appropriate.


Gynecology_Novak

Gynecology_Novak. Because pulmonary embolism is the leading cause of death following gynecologic surgical procedures, the use of prophylactic venous thromboembolism regimens is an essential part of management. In patients at moderate risk, intermittent pneumatic compression (IPC) during and after gynecologic surgery reduces the incidence of deep venous thrombosis on a level similar to that of low-dose or low molecular weight heparin. A combination of mechanical (IPC) and pharmacologic prophylaxis is recommended for high-risk patients. Patients who are predisposed to cardiovascular, respiratory, and endocrine illnesses must be thoroughly evaluated preoperatively. Coronary artery disease and chronic obstructive pulmonary disease (COPD) are major risk factors for patients undergoing abdominal surgery. Patients with hypertension should receive medication to control their blood pressure before surgery. Perioperative management of medical complications must be prompt and meticulous.


Gynecology_Novak

Gynecology_Novak. The successful outcome of gynecologic surgery is based on thorough evaluation, careful preoperative preparation, and attentive postoperative care. This chapter discusses approaches to the general perioperative management of patients undergoing major gynecologic surgery with specific medical problems that could complicate the surgical outcome. Gynecologic surgery should be undertaken only after gaining a thorough understanding of a patient’s medical history and performing a complete physical examination. 1. The medical history should include detailed questions to identify any medical illnesses that might be aggravated by surgery or anesthesia. Coronary artery disease, pulmonary diseases, and obesity are the most common causes of postoperative complications. 2.


Gynecology_Novak

Gynecology_Novak. 2. Medications currently being taken (including nonprescription drugs) and those discontinued within the month before surgery should be recorded. Information about the use of “alternative therapies,” herbs, and vitamins should be elicited (1,2). Specific instructions must be given to the patient regarding the need to discontinue any medications before surgery (e.g., aspirin, antiplatelet agents, diuretics, hormone replacement, or oral contraceptives), and those medications that should be continued (e.g., beta-blockers, α-2 agonists, statins, H2 blockers, and proton pump inhibitors). Collaboration with the anesthesiologist in making decisions about continuing preoperative medications is essential. In the case of herbal medications, there is no evidence that herbal medications improve surgical outcomes and many may increase complications (Table 22.1). It is recommended that all herbal medications be discontinued at least a week before surgery. 3.


Gynecology_Novak

Gynecology_Novak. 3. The patient should be questioned regarding known allergies to medications (e.g., sulfa and penicillin), foods, or environmental agents. A history of sensitivity to shellfish may be the only clue of iodine sensitivity, which could be fatal if intravenous contrast is administered without corticosteroid preparation. 4.


Gynecology_Novak

Gynecology_Novak. 4. Previous surgical procedures, and the patient’s course following those surgical procedures, should be reviewed to identify and protect against potential complications. The patient should be asked about specific complications, such as excessive bleeding, wound infection, venous thromboembolism, peritonitis, or bowel obstruction. Prior pelvic surgery should alert the gynecologist to the possibility of distorted surgical anatomy such as adhesions or ureteral stricture from previous periureteral scarring. In such cases, it may be prudent to identify any preexisting abnormality by performing computed tomography (CT) or other imaging. Many patients may not be entirely clear about the extent of the previous surgical procedure or the details of intraoperative findings. Therefore, operative notes from previous procedures should be obtained and reviewed. 5. Family history may identify familial traits that might complicate planned surgery.


Gynecology_Novak

Gynecology_Novak. 5. Family history may identify familial traits that might complicate planned surgery. A family history of excessive intraoperative or postoperative bleeding, venous thromboembolism, malignant hyperthermia, and other potentially inherited conditions should be sought. 6. The review of systems should be detailed to identify any coexisting medical or surgical conditions. Inquiry about gastrointestinal and urologic function is particularly important before undertaking pelvic surgery because many gynecologic diseases involve adjacent nongynecologic viscera. The patient may have less serious symptoms, which could be corrected along with performing the primary surgery (e.g., stress urinary incontinence, fecal soiling, symptomatic cystocele). 7.


Gynecology_Novak

Gynecology_Novak. 7. Although many women undergoing gynecologic surgical procedures are otherwise healthy, with pathology identified only on pelvic examination, other major organ systems should not be neglected in the physical examination. Identification of abnormalities, such as a heart murmur, pulmonary compromise, hernia, or osteoarthritis of hips or knees should lead the surgeon to obtain additional testing and consultation to minimize intraoperative and postoperative complications.


Gynecology_Novak

Gynecology_Novak. Table 22.1 Potential Effects of Common Herbal and Dietary Supplements “Routine” preoperative laboratory testing of healthy women is to be discouraged as abnormal results are infrequent and are rarely of consequence in the surgical or anesthetic management of the patient (3). Despite well-established guidelines, approximately 90% of patients undergo unnecessary testing in a major university medical center (4). The selection of appropriate preoperative laboratory studies should depend on the type of the anticipated surgical procedure and the patient’s medical status. Chest x-ray: Over age 60 years undergoing major surgery American Society of Anesthesiologists (ASA) 3 or greater Cardiovascular disease Electrocardiogram (5): Over age 60 years undergoing major surgery Any cardiovascular disease or diabetes Complete blood count: Major surgery ASA 3 or greater


Gynecology_Novak

Gynecology_Novak. Electrocardiogram (5): Over age 60 years undergoing major surgery Any cardiovascular disease or diabetes Complete blood count: Major surgery ASA 3 or greater Renal function: Recognized renal or cardiovascular disease Coagulation studies (activated partial thromboplastin time [APTT], prothrombin time [PT], platelet count): Not recommended unless patient has history of bleeding or liver disease (6) Urinalysis: Not recommended; may be considered given symptoms or history Imaging of adjacent organ systems should be undertaken in individual cases as follows: 1. CT urography is helpful to delineate ureteral patency and course, especially in the presence of a pelvic mass, gynecologic cancer, or congenital m¨ullerian anomaly. A CT urogram is not of value in the evaluation of most patients undergoing pelvic surgery (7). 2.


Gynecology_Novak

Gynecology_Novak. 2. Upper endoscopy, colonoscopy, barium enema, or upper gastrointestinal studies with small bowel assessment may be of value in evaluating some patients before undergoing pelvic surgery. Because of the proximity of the female genital tract to the lower gastrointestinal tract, the rectum and sigmoid colon may be involved with benign (endometriosis or pelvic inﬂammatory disease) or malignant gynecologic conditions. Conversely, a pelvic mass could have a gastrointestinal origin such as a diverticular abscess or a mass of inﬂamed small intestines (Crohn disease) or, rarely, a gastric or pancreatic carcinoma. Any patient with gastrointestinal symptoms should be further evaluated. 3. Other imaging studies, including ultrasonography, CT scanning, or magnetic resonance imaging (MRI), may be useful in selected patients such as in the evaluation of a pelvic mass.


Gynecology_Novak

Gynecology_Novak. 3. Other imaging studies, including ultrasonography, CT scanning, or magnetic resonance imaging (MRI), may be useful in selected patients such as in the evaluation of a pelvic mass. The preoperative discussion should include a description of the surgical procedure, its expected outcome and risks and is the basis for obtaining signed informed consent (8,9). Informed consent is an educational process for the patient and her family and fulfills the physician’s need to convey information in understandable terms. The items listed in Table 22.2 should be discussed, and, after each item, the patient and family should be invited to ask questions. Documentation of the discussion is an important component of the patient’s record that the physician should always include with the preprinted consent form.


Gynecology_Novak

Gynecology_Novak. Following are components of the informed consent process: 1. A discussion of the nature and the extent of the disease process should include an explanation in lay terms of the significance of the disease or condition. Printed materials, computer-based learning programs, and videotapes may assist in this process. The patient’s competency to understand the discussion and written consent should be assessed. If the patient speaks a different language, a qualified interpreter should be present and the presence of the interpreter documented. Table 22.2 Outline of Key Points of the Preoperative Informed Consent Discussion 1. The nature and extent of the disease process 2. The extent of the actual operation proposed and the potential modifications of the operation, depending on intraoperative findings 3. The anticipated benefits of the operation, with a conservative estimate of successful outcome 4. The risks and potential complications of the surgery 5.


Gynecology_Novak

Gynecology_Novak. The anticipated benefits of the operation, with a conservative estimate of successful outcome 4. The risks and potential complications of the surgery 5. Alternative methods of therapy and the risks and results of those alternative methods of therapy 6. The results likely if the patient is not treated 2. The goals of surgery should be discussed in detail. Some gynecologic surgical procedures are performed purely for diagnostic purposes (e.g., dilation and curettage, cold knife conization, diagnostic laparoscopy), whereas most are aimed at correcting a specific problem. The extent of the surgery should be outlined, including which organs will be removed. Most patients like to be informed regarding the type of surgical incision and the estimated duration of anesthesia. 3.


Gynecology_Novak

Gynecology_Novak. The expected outcome of the surgical procedure should be explained. If the procedure is being performed for diagnostic purposes, the outcome will depend on surgical or pathologic findings that are not known before surgery. When treating an anatomic deformity or disease, the expected success of the operation should be discussed, and the potential for failure of the operation (e.g., failure of tubal sterilization or the possibility that stress urinary incontinence may not be alleviated). When treating cancer, the possibility of finding more advanced disease and the potential need for adjunctive therapy (e.g., postoperative radiation therapy or chemotherapy) should be mentioned. Other issues of importance to the patient include discussion of loss of fertility or loss of ovarian function. These issues should be raised by the physician to ensure that the patient adequately understands the pathophysiology that may result from the surgery and to allow her to express her feelings regarding


Gynecology_Novak

Gynecology_Novak. issues should be raised by the physician to ensure that the patient adequately understands the pathophysiology that may result from the surgery and to allow her to express her feelings regarding these emotionally charged issues. Unanticipated findings at the time of surgery should be mentioned. For example, if the ovaries are unexpectedly found to be diseased, the best surgical judgment may be that they should be removed.


Gynecology_Novak

Gynecology_Novak. 4.


Gynecology_Novak

Gynecology_Novak. The risks and potential complications of the surgical procedure should be discussed, including the most frequent complications of the particular surgical procedure. For most major gynecologic surgery, the risks include intraoperative and postoperative hemorrhage, postoperative infection, venous thromboembolism, injury to adjacent viscera, and wound complications. The patient should understand that minimally invasive surgery may have many of the same risks of injury or complications as does “open” surgery. Given the potential for transfusion of blood products, it should be clarified whether the patient would object to receiving a transfusion. Preexisting medical problems (e.g., diabetes, obesity, chronic obstructive pulmonary disease [COPD], coronary artery disease) result in additional risks and should be reviewed with the patient. Measures that will be taken to reduce the risk of complications should be described (e.g., prophylactic antibiotics, bowel preparation, venous


Gynecology_Novak

Gynecology_Novak. risks and should be reviewed with the patient. Measures that will be taken to reduce the risk of complications should be described (e.g., prophylactic antibiotics, bowel preparation, venous thromboembolism prophylaxis).


Gynecology_Novak

Gynecology_Novak. 5. The usual postoperative course should be discussed in enough detail to allow the patient to understand what to expect in the days following surgery. Information regarding the need for a suprapubic catheter, prolonged central venous monitoring, or an intensive care stay helps the patient accept her postoperative course and avoids surprises to the patient and her family that may be disconcerting. The expected duration of the recovery period, both in and out of the hospital, should be outlined. 6. Alternative methods of therapy should be discussed, including medical management or other surgical approaches. The patient should have an understanding of the outcome of the disease if nothing is done.


Gynecology_Novak

Gynecology_Novak. Nutrition Young patients undergoing elective gynecologic surgery have adequate nutritional stores and, for the most part, do not require nutritional support. All patients should have a nutritional assessment, especially elderly patients and those undergoing gynecologic cancer surgery or other major gynecologic procedures in which a prolonged postoperative recovery is expected. Nutritional status should be reassessed at regular intervals postoperatively until the patient successfully returns to a regular diet.


Gynecology_Novak

Gynecology_Novak. A nutritional assessment includes a careful history and physical examination, which are the most useful, reliable, and cost-effective methods of determining a patient’s nutritional status. In particular, information about recent weight loss, dietary history, fad diets, extreme exercise, or anorexia or bulimia should be elucidated. Physical evidence of malnutrition includes temporal wasting, muscle wasting, ascites, and edema. Accurate height and weight measurements should be obtained and an ideal body weight, percentage ideal body weight, and percentage usual body weight may be calculated. Many Internet-based body weight calculators are available. A variety of techniques were developed to determine a patient’s nutritional state; however, many methods lack clinical utility outside of a research setting. Anthropometric measurements of skin-fold thickness and arm-muscle circumference provide an estimate of total body fat and lean muscle mass.


Gynecology_Novak

Gynecology_Novak. The calculated body mass index (BMI) can be used as a surrogate marker for nutritional status. The BMI is calculated as body weight in kilograms divided by the height in square centimeters. A BMI less than 22 increases the risk of malnutrition, and a BMI less than 19 gives clear evidence of malnutrition (10).


Gynecology_Novak

Gynecology_Novak. Patients who have lost less than 6% of their ideal body weight do not need preoperative nutritional intervention. However, patients who have lost more than 10% of their ideal body weight in 6 months meet the definition of severely malnourished and should be considered for preoperative intervention (11). Patients who have lost between 6% and 10% should undergo further studies to determine if preoperative intervention is needed. Laboratory assessments of albumin, transferrin, and prealbumin may be obtained in addition to the routine preoperative tests. The degree of malnutrition can in part be determined by serum concentrations of albumin, transferrin, and prealbumin. The levels of these serum proteins are greatly inﬂuenced by the patient’s level of hydration. Prealbumin has the shortest half-life, at 2 to 3 days, and levels of this protein are depressed very early in comparison with serum transferrin and albumin, which have half-lives of 8 and 20 days, respectively (12). Serum albumin


Gynecology_Novak

Gynecology_Novak. at 2 to 3 days, and levels of this protein are depressed very early in comparison with serum transferrin and albumin, which have half-lives of 8 and 20 days, respectively (12). Serum albumin is a substitute for the Prognostic Nutritional Index, which is a time-consuming calculation, in assessing malnutrition in women with gynecologic malignancies (13). A serum albumin level of 3.5 to 5.0 is in the normal range, 2.8 to 3.4 is considered to indicate mild malnutrition, 2.1 to 2.7 moderate malnutrition, and less than 2.1 severe malnutrition (14). Hypoalbuminemia is correlated with morbidity, mortality, and increased postoperative complication rates in data from the National Surgical Quality Improvement Program (15). Decisions regarding the need for nutritional support should be based on several individualized factors. These factors include the patient’s prior nutritional state, the anticipated length of time in which the patient will not be able to eat, the severity of surgery, and the


Gynecology_Novak

Gynecology_Novak. individualized factors. These factors include the patient’s prior nutritional state, the anticipated length of time in which the patient will not be able to eat, the severity of surgery, and the likelihood of complications. The nutritional assessment should determine whether the cause of the malnutrition is increased enteral loss (malabsorption, intestinal fistula), decreased oral intake, increased nutritional requirements as a result of hypermetabolism (sepsis, malignancy), or a combination of these factors. Severe malnutrition, if not corrected, can further complicate the postoperative problem by causing altered immune function, chronic anemia, impaired wound healing, and eventually multiple organ system failure and death.


Gynecology_Novak

Gynecology_Novak. The patient’s nutritional requirements are increased by surgery for several reasons. First, there is a period following surgery during which oral intake is not allowed or is very limited. In addition, the operation itself causes increased protein catabolism, increased energy requirements, and a negative nitrogen balance. If the surgery is uncomplicated and the patient is without food for less than 7 days, this response is limited and patients usually recover without the need for nutritional support. An adequate diet is defined as providing 75% of estimated caloric and protein needs. Therefore, if an adequate oral diet is not expected for 7 to 10 days, perioperative nutritional support may be required to avoid progressive malnutrition and associated complications (14). Perioperative nutritional support reduces operative morbidity and decreases the length of hospitalization when commenced early in the postoperative course. Patients with either normal nutritional indices or mild or


Gynecology_Novak

Gynecology_Novak. support reduces operative morbidity and decreases the length of hospitalization when commenced early in the postoperative course. Patients with either normal nutritional indices or mild or moderate malnutrition, who will be undergoing surgical procedures likely to require a prolonged catabolic period of more than 7 to 10 days, should have enteral or parenteral nutrition instituted in the early postoperative period as soon as the patient is hemodynamically stable. This type of management should be strongly considered in patients undergoing pelvic exenterations, urinary diversions, or multiple enterectomies (16). Preoperative nutritional support is indicated for patients who have significant preexisting malnutrition or require major elective surgery. According to the American Society for Parenteral and Enteral Nutrition (ASPEN) guidelines, evidence-based medicine supports the use of preoperative nutritional support for 7 to 14 days in moderately to severely malnourished patients


Gynecology_Novak

Gynecology_Novak. for Parenteral and Enteral Nutrition (ASPEN) guidelines, evidence-based medicine supports the use of preoperative nutritional support for 7 to 14 days in moderately to severely malnourished patients undergoing major nonemergent gastrointestinal surgery (12). A Veterans Affairs Total Parenteral Nutrition Cooperative Study found that severely malnourished patients preconditioned with total parenteral nutrition (TPN) had fewer complications than did control patients, excluding infectious complications (17). In a meta-analysis review of 22 studies of preoperative TPN use, a 10% decrease in postoperative complications occurred in TPN-supported patients (18). In a prospective trial including 108 women with ovarian cancer who underwent surgical cytoreduction, 88 patients had prealbumin levels less than 18 mg/dL and 24 had prealbumin levels less than 10 mg/dL (19). All postoperative mortality (23%) and 61.5% of all complications occurred in women with prealbumin less than 10 mg/dL. Women who


Gynecology_Novak

Gynecology_Novak. than 18 mg/dL and 24 had prealbumin levels less than 10 mg/dL (19). All postoperative mortality (23%) and 61.5% of all complications occurred in women with prealbumin less than 10 mg/dL. Women who received preoperative TPN and had prealbumin levels that increased to greater than 10 mg/dL did not have significantly increased complications. These findings lend support to consideration of preoperative TPN or neoadjuvant chemotherapy with interval cytoreduction when the nutritional status improves. These findings are encouraging but not supported by all studies or meta-analyses (20). If preoperative TPN is prescribed, it should be tapered and stopped at midnight before surgery, restarted 24 to 72 hours after the procedure, and continued until the patient is able to meet nutritional requirements.


Gynecology_Novak

Gynecology_Novak. ASPEN guidelines do not support the routine use of nutritional support in the immediate postoperative period for patients undergoing major gastrointestinal surgery; however, the guidelines do indicate a role for nutritional support postoperatively in patients in whom oral intake will be inadequate for 7 to 10 days (12). Clinical trials demonstrate that TPN can improve nutritional status as measured by biochemical assays, immune function, and nitrogen balance. The effect of TPN on clinical outcome is less well established. Despite what seems reasonable, based on common sense and preoperative nutritional parameters, the data do not support TPN for mild to moderately malnourished patients. With severe malnutrition, preoperative TPN seems to be beneficial and should be instituted.


Gynecology_Novak

Gynecology_Novak. Route of Administration After the decision is made that nutritional support is required, the appropriate route of administration must be determined. Enteral nutrition should be considered primarily because it is easy to deliver, associated with the fewest complications, linked to enhanced wound healing, and relatively inexpensive (21). Contraindications to this route of delivery include intestinal obstruction, gastrointestinal bleeding, and diarrhea. Many types of preparations are commercially available and can be chosen based on their caloric content, fat content, protein content, osmolality, viscosity, and price. Depending on the patient’s problem, the route of delivery may be through a Dobhoff feeding tube, a gastrostomy tube, or a feeding jejunostomy tube (22). If the gastrointestinal tract is unusable for more than 7 days postoperatively, TPN should be implemented.


Gynecology_Novak

Gynecology_Novak. Total parenteral nutrition must be delivered through a central vein and has wide acceptance as a means of providing nutritional support for surgically ill patients. It must be delivered through a subclavian or internal jugular vein, and the catheter must be placed using meticulous sterile surgical technique. Only intravenous access lines in the right atrium, superior vena cava, or inferior vena cava can be truly deemed central lines (23). Proper daily care is required to avoid infectious complications. When managed by an experienced team, the most frequent complication, infection, can be minimized (24).


Gynecology_Novak

Gynecology_Novak. maximal rate of glucose oxygenation in adults is approximately 7 g/kg/day, and glucose administration in excess of the caloric requirements can lead to fatty infiltration of the liver and other metabolic complications. When given by TPN infusion, the dextrose tolerance in critically ill patients is 5 mg/kg/min (24). Insulin should be used to maintain serum glucose concentration between 150 and 250 mg/dL, and it may be added directly to the TPN solution. 4.


Gynecology_Novak

Gynecology_Novak. Fats. Lipids in a 10% to 20% emulsion can be given as further caloric supplement and supply the essential fatty acids, linoleic acid, and α-linoleic acids. More calories can be given in the form of free fatty acids, which are the major source of energy for most peripheral tissues. When lipids are used as a major source of calories, a minimum of 50 to 150 g per day of glucose should also be given to provide a substrate for the central nervous system. Most patients can tolerate up to 2 g of fat per kilogram of weight per day, and daily dosages should not exceed4goffatper kilogram of weight per day. In critically ill patients, the lipid content should not exceed 1 g/kg/day. These lipid emulsions are isotonic and can be delivered simultaneously with the protein and carbohydrate mixture in a 3-L bag over a 24-hour infusion. In general, 30% to 50% of nonprotein calories should be supplied in lipid form. Serum triglyceride levels should be monitored to ensure that the patient can metabolize


Gynecology_Novak

Gynecology_Novak. bag over a 24-hour infusion. In general, 30% to 50% of nonprotein calories should be supplied in lipid form. Serum triglyceride levels should be monitored to ensure that the patient can metabolize the fat.


Gynecology_Novak

Gynecology_Novak. 5. Electrolytes, vitamins, and minerals. In addition to calories and protein, nutritional support should be maintained in terms of electrolytes, vitamins, and trace elements. Daily maintenance requirements for electrolytes are as follows: sodium, 40 to 50 mEq; potassium, 30 to 40 mEq; magnesium, 8 to 10 mEq; calcium, 2 to 5 mEq; and phosphate, 13 to 25 mmol (24). A number of vitamins and trace elements must also be supplied to ensure that the patient is eumetabolic. Fluid and Electrolytes Water constitutes approximately 50% to 55% of the body weight of the average woman. Two-thirds of this water is contained in the intracellular compartment. One-third is contained in the extracellular compartment, of which one-fourth is contained in plasma, and the remaining three-fourths is in the interstitium.


Gynecology_Novak

Gynecology_Novak. Osmolarity, or tonicity, is a property derived from the number of particles in a solution. Sodium and chloride are the primary electrolytes contributing to the osmolarity of the extracellular compartment. Potassium and, to a lesser extent, magnesium and phosphate are the major intracellular electrolytes. Water ﬂows freely between the intracellular and the extracellular spaces to maintain osmotic neutrality throughout the body. Any shifts in osmolarity in any ﬂuid spaces within the body are accompanied by corresponding shifts in free water from spaces of lower to higher osmolarity, thus maintaining equilibrium.


Gynecology_Novak

Gynecology_Novak. The average adult daily ﬂuid maintenance requirement is approximately 30 mL/kg/day, or 2,000 to 3,000 mL per day (26). This level is offset partially by insensible losses of 1,200 mL per day, which include losses from the lungs (600 mL), skin (400 mL), and gastrointestinal tract (200 mL). Urinary output from the kidney accounts for the remainder of the ﬂuid loss, and this output will vary depending on total body intake of water and sodium. Approximately 600 to 800 mOsm of solute are excreted by the kidneys daily. Healthy kidneys can concentrate urine up to approximately 1,200 mOsm and, therefore, the minimum output can range between 500 and 700 mL per day. The maximal urine output of the kidney can be as high as 20 L per day, as seen in patients with diabetes insipidus. In healthy individuals, the kidney adjusts output commensurate with daily ﬂuid intake.


Gynecology_Novak

Gynecology_Novak. The major extracellular buffer used in the acid-base balance is the bicarbonate-carbonic acid system: CO2 + H2O ↔ H2CO3 ↔ H++ HCO3 + (27). Typically, the body will maintain a bicarbonate-to-carbonic acid ratio of 20:1 to maintain an extracellular pH of 7.4. Both the lung and the kidney play integral roles in the maintenance of normal extracellular pH via retention or excretion of carbon dioxide and bicarbonate. Under conditions of alkalosis, minute ventilation decreases and renal excretion of bicarbonate increases to restore the normal ratio of bicarbonate to carbonic acid; the opposite occurs with acidosis.


Gynecology_Novak

Gynecology_Novak. Ultimately, the kidney plays the most important role in ﬂuid and electrolyte balance through excretion and retention of water and solute. Circulating antidiuretic hormone and aldosterone help modulate the process. Serum osmolarity affects hypothalamic release of antidiuretic hormone and aldosterone secretion in response to renal perfusion. Under states of dehydration or hypovolemia, serum antidiuretic hormone levels increase, leading to increased resorption of water in the distal tubule of the kidney. Increased aldosterone release promotes increased sodium and water retention. The opposite occurs in states of ﬂuid excess. Individuals with normal renal function and circulating antidiuretic hormone and aldosterone levels maintain normal serum osmolarity and electrolyte composition, despite daily ﬂuctuations of ﬂuid and electrolyte intake.


Gynecology_Novak

Gynecology_Novak. Various disease states can alter the normal ﬂuid and electrolyte homeostatic mechanisms, making perioperative ﬂuid and electrolyte management more difficult. Patients with intrinsic renal disease are unable to excrete solute and to maintain acid-base balance. In patients undergoing the stress of chronic starvation or severe illness, there may be an inappropriately high level of circulating antidiuretic hormone and aldosterone, resulting in ﬂuid and sodium retention. With severe cardiac disease, secondary renal hypoperfusion can lead to increased aldosterone synthesis and increased sodium and water retention by the kidney. Patients with severe diabetes can have significant osmotic diuresis as well as acid-base dysfunction secondary to circulating keto acids. Treatment of renal, cardiac, or endocrine disorders preoperatively is imperative and often will rectify ﬂuid and electrolyte abnormalities.


Gynecology_Novak

Gynecology_Novak. Special attention is warranted in the elderly patient undergoing surgery. Normal physiological changes associated with aging can increase the likelihood of ﬂuid and electrolyte disorders. These changes include decreased glomerular filtration rate, decreased urinary concentrating ability, and narrowed limits for excretion of water and electrolytes (28). Fluid and electrolyte management in the perioperative period requires knowledge of the daily ﬂuid and electrolyte requirements for maintenance, replacement of ongoing ﬂuid and electrolyte losses, as well as correction of any existing abnormalities.


Gynecology_Novak

Gynecology_Novak. The body adjusts to higher and lower volumes of intake by changes in plasma tonicity. Alterations in plasma tonicity induce adjustments in circulating antidiuretic hormone levels, which ultimately regulate the amount of water retained in the distal tubule of the kidney. In the preoperative and the early postoperative periods, it is usually necessary to replace only sodium and potassium. Chloride is automatically replaced, concomitant with sodium and potassium, because chloride is the usual anion used to balance sodium and potassium in electrolyte solutions. There are various commercially available solutions containing 40 mmol of sodium chloride, with smaller amounts of potassium, calcium, and magnesium, designed to meet the requirements of a patient who is receiving3Lof intravenous ﬂuids per day. The daily requirement can be met by any combination of intravenous ﬂuids. For example, 2 L of D5 (5% dextrose)/0.45 normal saline (7 mEq sodium chloride each), supplemented with 20 mEq of


Gynecology_Novak

Gynecology_Novak. per day. The daily requirement can be met by any combination of intravenous ﬂuids. For example, 2 L of D5 (5% dextrose)/0.45 normal saline (7 mEq sodium chloride each), supplemented with 20 mEq of potassium chloride, followed by 1 L of D5W (5% dextrose in water) with 20 mEq of potassium chloride, would suffice.


Gynecology_Novak

Gynecology_Novak. Fluid and electrolyte losses beyond the daily average must be replaced by appropriate solutions. The choice of solutions for replacement depends on the composition of the ﬂuids lost. Often, it is difficult to measure free water loss, particularly in patients who have high losses from the lungs, skin, or the gastrointestinal tract. Weighing these patients daily can be very useful. Up to 300 g of weight loss daily can be attributable to weight loss from catabolism of protein and fat in the patient who is taking nothing by mouth (26). Any loss beyond this level represents ﬂuid loss, which should be replaced accordingly. Patients with a high fever can have increased pulmonary and skin loss of free water, sometimes in excess of 2 to 3 L per day. These losses should be replaced with free water in the form of D5W. Perspiration typically has one-third the osmolarity of plasma and can be replaced with D5W or, if the loss is excessive, with D5/0.25 normal saline.


Gynecology_Novak

Gynecology_Novak. Patients with acute blood loss need replacement with appropriate isotonic ﬂuid or blood or both. There is a wide range of plasma volume expanders, including albumin, dextran, and hetastarch solutions, that contain large molecular weight particles (<50 kDa molecular weight). These particles are slow to exit the intravascular space, and about one-half of the particles remain after 24 hours. Controversy exists over the ideal strategy for intravascular volume replacement (29). A systematic review of 25 randomized clinical trials demonstrated preserved renal function and reduced intestinal edema in surgical patients receiving hyperoncotic albumin solutions, as compared with control ﬂuids (30). Meta-analyses on the use of human albumin and crystalloids versus colloids in ﬂuid resuscitation did not show a benefit in mortality rates (31,32). Caution


Gynecology_Novak

Gynecology_Novak. Correction of Existing Fluid and Electrolyte Abnormalities is required in interpreting results from these pooled controlled trials because mortality outcome was not the end point of most of the studies, and publication bias is a limitation. Possible side effects with synthetic colloid solutions include adverse affects on hemostasis, severe anaphylactic reactions, and impairment of renal function (29). These solutions are expensive and for most cases, simple replacement with 0.9 normal saline or lactated Ringer’s solution will suffice. One-third of the volume of lactated Ringer’s solution or normal saline typically will remain in the intravascular space and the remainder goes to the interstitium.


Gynecology_Novak

Gynecology_Novak. One-third of the volume of lactated Ringer’s solution or normal saline typically will remain in the intravascular space and the remainder goes to the interstitium. Appropriate replacement of gastrointestinal ﬂuid loss depends on the source of ﬂuid loss in the gastrointestinal tract. Gastrointestinal secretions beyond the stomach and up to the colon are typically isotonic with plasma, with similar amounts of sodium, slightly lower amounts of chloride, slightly alkaline pH, and more potassium (in the range of 10 to 20 mEq/L). Under normal conditions, stool is hypotonic. However, under conditions of increased ﬂow (i.e., severe diarrhea), stool contents are isotonic with a composition similar to that of the small bowel contents. Gastric contents are typically hypotonic, with one-third the sodium of plasma, increased amounts of hydrogen ion, and low pH.


Gynecology_Novak

Gynecology_Novak. In patients who have gastric outlet obstruction, nausea, and vomiting, or who undergo nasogastric suction, appropriate replacement of gastric secretions can be provided with a solution such as D5/0.45 normal saline with 20 mEq/L of potassium. Potassium supplementation is particularly important to prevent hypokalemia in these patients, whose kidneys attempt to conserve hydrogen ions in the distal tubule of the kidney in exchange for potassium ions. In patients with bowel obstruction, 1 to 3 L of ﬂuid can be sequestered daily in the gastrointestinal tract. This ﬂuid should be replaced with isotonic saline or lactated Ringer’s solution. Similarly, patients with enterocutaneous fistulas or new ileostomies should receive replacement with isotonic ﬂuids.


Gynecology_Novak

Gynecology_Novak. Patients who have ﬂuid or electrolyte abnormalities preoperatively can pose a diagnostic challenge. The correct diagnosis and therapy is contingent on a correct assessment of total body ﬂuid and electrolyte status. The management of hyponatremia, for example, may be either ﬂuid restriction or ﬂuid replacement. The choice of treatment depends on whether there is overall extracellular ﬂuid excess and normal body sodium stores or decreased overall total body sodium stores and extracellular ﬂuid. A detailed history is necessary to disclose any underlying medical illness and to assess the amount and duration of any abnormal ﬂuid losses or intake. Initial evaluation should include an assessment of hemodynamic, clinical, and urinary parameters to determine the overall level of hydration as well as the ﬂuid status of the extracellular ﬂuid compartment. The patient who has good skin turgor, moist mucosa, stable vital signs, and good urinary output is well hydrated. Nonpitting edema is


Gynecology_Novak

Gynecology_Novak. as well as the ﬂuid status of the extracellular ﬂuid compartment. The patient who has good skin turgor, moist mucosa, stable vital signs, and good urinary output is well hydrated. Nonpitting edema is indicative of extracellular ﬂuid excess, whereas patients with orthostasis, sunken eyes, parched mouth, and decreased skin turgor have extracellular volume contraction. A patient’s overall extracellular ﬂuid status does not always reﬂect the hydration status of the intravascular compartment. A patient can have increased interstitial ﬂuid and yet be intravascularly dry, requiring replacement with isotonic ﬂuid.


Gynecology_Novak

Gynecology_Novak. The laboratory workup for patients who may have preexisting ﬂuid problems should include assessment of blood hematocrit, serum chemistry, glucose, blood urea nitrogen (BUN) and creatinine, urine osmolarity, and urine electrolyte levels. Serum osmolarity is mainly a function of the concentration of sodium and is given by the following equation: 2[Na+] + glucose (mg/dL)/18 + BUN (mg/dL)/2.8


Gynecology_Novak

Gynecology_Novak. Normal serum osmolarity is typically 290 to 300 mOsm. Blood hematocrit will rise or fall inversely at a rate of 1% per 500-mL alteration of extracellular ﬂuid volume. The BUN:creatinine ratio is typically 10:1 but will rise to a ratio of greater than 20:1 under conditions of extracellular ﬂuid contraction. Under conditions of extracellular ﬂuid deficit, urine osmolarity will typically be high (>400 mOsm), whereas urine sodium concentration is low (<15 mEq/L), indicative of an attempt by the kidney to conserve sodium. Under conditions of extracellular ﬂuid excess or in cases of renal disease in which the kidney has impaired ability to retain sodium and water, urine osmolarity will be low and urine sodium will be high (>30 mEq/L). Changes in sodium can give insight into the degree of extracellular ﬂuid excess or deficit. In the average person, the serum sodium rises by 3 mmol/L for every liter of water deficit and falls by 3 mmol/L for each liter of water excess. One must be careful in


Gynecology_Novak

Gynecology_Novak. ﬂuid excess or deficit. In the average person, the serum sodium rises by 3 mmol/L for every liter of water deficit and falls by 3 mmol/L for each liter of water excess. One must be careful in making these estimates because patients with prolonged water and electrolyte loss can have low serum sodium levels and marked water deficits.


Gynecology_Novak

Gynecology_Novak. Because sodium is the major extracellular cation, shifts in serum sodium levels are usually inversely correlated with the hydration state of the extracellular ﬂuid compartment. The pathophysiology of hyponatremia is usually expansion of body ﬂuids leading to excess total body water (27,33). Symptomatic hyponatremia usually does not occur until the serum sodium is below 120 to 125 mEq/L. The severity of the symptoms (nausea, vomiting, lethargy, seizures) is related more to the rate of change of serum sodium than to the actual serum sodium level.


Gynecology_Novak

Gynecology_Novak. Hyponatremia in the form of extracellular ﬂuid excess can be seen in patients with renal or cardiac failure and in conditions such as nephrotic syndrome, in which total body salt and water are increased, with a relatively greater increase in the latter. Administration of hypertonic saline to correct the hyponatremia would be inappropriate in this setting. The treatment should include, in addition to correcting the underlying disease process, water restriction with diuretic therapy. Inappropriate secretion of antidiuretic hormone (ADH) can occur with head trauma, pulmonary or cerebral tumors, and states of stress. The abnormally elevated ADH results in excess water retention. Treatment includes water restriction and, if possible, correction of the underlying cause. Demeclocycline, a tetracycline antibiotic, is effective in this disorder via its action in the kidney. The introduction of vasopressin receptor antagonists, such as tolvaptan, may replace demeclocycline as the drug of choice


Gynecology_Novak

Gynecology_Novak. antibiotic, is effective in this disorder via its action in the kidney. The introduction of vasopressin receptor antagonists, such as tolvaptan, may replace demeclocycline as the drug of choice for the syndrome of inappropriate ADH secretion (34).


Gynecology_Novak

Gynecology_Novak. Inappropriate replacement of body salt losses with water alone will result in hyponatremia. This situation will typically occur in patients who lose large amounts of electrolytes secondary to vomiting, nasogastric suction, diarrhea, or gastrointestinal fistulas, and who received replacement with hypotonic solutions. Simple replacement with isotonic ﬂuids and potassium will usually correct the abnormality. Rarely, rapid correction of the hyponatremia is necessary, in which case hypertonic saline (3%) can be administered. Hypertonic saline should be administered very cautiously to avoid a rapid shift in serum sodium, which will induce central nervous system dysfunction.


Gynecology_Novak

Gynecology_Novak. Hypernatremia is an uncommon condition that can be life-threatening if severe (serum sodium greater than 160 mEq/L). The pathophysiology is extracellular ﬂuid deficit. The resultant hyperosmolar state leads to decreased water volume in cells in the central nervous system, which, if severe, can cause disorientation, seizures, intracranial bleeding, and death. The causes include excessive extrarenal water loss, which can occur in patients who have a high fever, have undergone tracheostomy in a dry environment, or have extensive thermal injuries; who have diabetes insipidus, either central or nephrogenic; and who have iatrogenic salt loading. The treatment involves correction of the underlying cause (correction of fever, humidification of the tracheostomy, administration of desmopressin for control of central diabetes insipidus) and replacement with free water either by the oral route or intravenously with D5W. As with severe hyponatremia, marked hypernatremia should be corrected slowly,


Gynecology_Novak

Gynecology_Novak. of central diabetes insipidus) and replacement with free water either by the oral route or intravenously with D5W. As with severe hyponatremia, marked hypernatremia should be corrected slowly, no faster than 10 mEq per day, unless the patient is symptomatic from severe acute hypernatremia (35).


Gynecology_Novak

Gynecology_Novak. Hypokalemia may be encountered preoperatively in patients with significant gastrointestinal ﬂuid loss (prolonged emesis, diarrhea, nasogastric suction, intestinal fistulas) and marked urinary potassium loss secondary to renal tubular disorders (renal tubular acidosis, acute tubular necrosis, hyperaldosteronism, prolonged diuretic use). It can arise from prolonged administration of potassium-free parenteral ﬂuids in patients who are restricted from ingesting anything by mouth. The symptoms associated with hypokalemia include neuromuscular disturbances, ranging from muscle weakness to ﬂaccid paralysis, and cardiovascular abnormalities, including hypotension, bradycardia, arrhythmias, and enhancement of digitalis toxicity. These symptoms rarely occur unless the serum potassium level is less than 3 mEq/L. The treatment is potassium replacement. Oral therapy is preferable in patients who are on an oral diet.


Gynecology_Novak

Gynecology_Novak. If necessary, potassium replacement can be given intravenously in doses that should not exceed 10 mEq per hour.


Gynecology_Novak

Gynecology_Novak. Hyperkalemia is encountered infrequently in preoperative patients. It is usually associated with renal impairment but can be seen in patients who have adrenal insufficiency, are taking potassium-sparing diuretics, and have marked tissue breakdown such as that occurring with crush injuries, massive gastrointestinal bleeding, or hemolysis. The clinical manifestations are mainly cardiovascular. Marked hyperkalemia (potassium >7 mEq/L) can result in bradycardia, ventricular fibrillation, and cardiac arrest. The treatment chosen depends on the severity of the hyperkalemia and whether there are associated cardiac abnormalities detected with electrocardiography. Calcium gluconate (10 mL of a 10% solution), given intravenously, can offset the toxic effects of hyperkalemia on the heart. One ampule each of sodium bicarbonate and D5W, with or without insulin, will cause a rapid shift of potassium into cells. Over the longer term, cation exchange resins such as sodium polystyrene sulfate


Gynecology_Novak

Gynecology_Novak. ampule each of sodium bicarbonate and D5W, with or without insulin, will cause a rapid shift of potassium into cells. Over the longer term, cation exchange resins such as sodium polystyrene sulfate (Kayexalate), taken orally or by enema, will bind and decrease total body potassium. Hemodialysis is reserved for emergent conditions in which other measures are not sufficient or have failed (35).


Gynecology_Novak

Gynecology_Novak. Several hormonal and physiologic alterations in the postoperative period may complicate ﬂuid and electrolyte management. The stress of surgery induces an inappropriately high level of circulating ADH. Circulating aldosterone levels are increased, especially if sustained episodes of hypotension occurred either intraoperatively or postoperatively. The elevated levels of circulating ADH and aldosterone make postoperative patients prone to sodium and water retention.


Gynecology_Novak

Gynecology_Novak. Total body ﬂuid postoperative volume may be altered significantly. First, 1 mL of free water is released for each gram of fat or tissue that is catabolized and, in the postoperative period, several hundred milliliters of free water are released daily from tissue breakdown, particularly in the patient who has undergone extensive intra-abdominal dissection and who is restricted from ingesting food and ﬂuids by mouth. This free water is often retained in response to the altered levels of ADH and aldosterone. Second, ﬂuid retention is further enhanced by third spacing, or sequestration of ﬂuid in the surgical field. The development of an ileus may result in an additional 1 to3Lof ﬂuid per day being sequestered in the bowel lumen, bowel wall, and peritoneal cavity. In contrast to renal sodium homeostasis, the kidney lacks the capacity for retention of potassium.


Gynecology_Novak

Gynecology_Novak. In contrast to renal sodium homeostasis, the kidney lacks the capacity for retention of potassium. In the postoperative period, the kidneys continue to excrete a minimum of 30 to 60 mEq/L of potassium daily, irrespective of the serum potassium level and total body potassium stores (27). If this potassium is not replaced, hypokalemia may develop. Tissue damage and catabolism during the first postoperative day usually result in the release of sufficient intracellular potassium to meet the daily requirements. Beyond the first postoperative day, potassium supplementation is necessary.


Gynecology_Novak

Gynecology_Novak. Correct maintenance of ﬂuid and electrolyte balance in the postoperative period starts with the preoperative assessment, with emphasis on establishing normal ﬂuid and electrolyte parameters before surgery. Postoperatively, close monitoring of daily weight, urine output, serum hematocrit, serum electrolytes, and hemodynamic parameters will yield the necessary information to make correct adjustments in crystalloid replacement. The normal daily ﬂuid and electrolyte requirements must be met and any unusual ﬂuid and electrolyte losses, including those from the gastrointestinal tract, lungs, or skin, must be compensated. After the first few postoperative days, third-space ﬂuid begins to return to the intravascular space, and ADH and aldosterone levels revert to normal. The excess ﬂuid retained perioperatively is mobilized and excreted through the kidneys, and exogenous ﬂuid requirements decrease. Patients with inadequate cardiovascular or renal reserve are prone to ﬂuid overload during this


Gynecology_Novak

Gynecology_Novak. is mobilized and excreted through the kidneys, and exogenous ﬂuid requirements decrease. Patients with inadequate cardiovascular or renal reserve are prone to ﬂuid overload during this time of third-space reabsorption, especially if intravenous ﬂuids are not appropriately reduced.


Gynecology_Novak

Gynecology_Novak. The most common ﬂuid and electrolyte disorder in the postoperative period is ﬂuid overload. Fluid excess can occur concomitantly with normal or decreased serum sodium. Large amounts of isotonic ﬂuids are usually infused intraoperatively and postoperatively to maintain blood pressure and urine output. Because the infused ﬂuid is often isotonic with plasma, it will remain in the extracellular space. Under such conditions, serum sodium will remain within normal levels. Fluid excess with hypotonicity (decreased serum sodium) can occur if large amounts of isotonic ﬂuid losses (e.g., blood and gastrointestinal tract) are inappropriately replaced with hypotonic ﬂuids. The predisposition toward retention of free water in the immediate postoperative period compounds the problem. An increase in body weight occurs concomitantly with the ﬂuid expansion. In the patient who is not allowed anything by mouth, catabolism should induce a daily weight loss as great as 300 g per day. The patient who is


Gynecology_Novak

Gynecology_Novak. weight occurs concomitantly with the ﬂuid expansion. In the patient who is not allowed anything by mouth, catabolism should induce a daily weight loss as great as 300 g per day. The patient who is gaining weight in excess of 150 g per day is in a state of ﬂuid expansion. Simple ﬂuid restriction will correct the abnormality. When necessary, diuretics can be used to increase urinary excretion.


Gynecology_Novak

Gynecology_Novak. States of ﬂuid dehydration are uncommon but will occur in patients who have large daily losses of ﬂuid that are not replaced. Gastrointestinal losses should be replaced with the appropriate ﬂuids. Patients with high fevers should be given appropriate free water replacement, because up to 2 L per day of free water can be lost through perspiration and hyperventilation. Although these increased losses are difficult to monitor, a reliable estimate can be obtained by monitoring body weight.


Gynecology_Novak

Gynecology_Novak. A variety of metabolic, respiratory, and electrolyte abnormalities in the postoperative period can result in an imbalance in normal acid-base homeostasis, leading to alkalosis or acidosis. Changes in the respiratory rate directly affect the amount of carbon dioxide that is exhaled. Respiratory acidosis will result from carbon dioxide retention in patients who have hypoventilation from central nervous system depression. This condition can result from oversedation with narcotics, particularly in the presence of concurrent severe chronic obstructive pulmonary disease. Respiratory alkalosis can result from hyperventilation caused by excitation of the central nervous system by drugs, pain, or excess ventilator support. Numerous metabolic derangements can result in metabolic alkalosis or acidosis. Proper ﬂuid and electrolyte replacement as well as maintenance of adequate tissue perfusion will help prevent most acid-base disorders that occur during the postoperative period.


Gynecology_Novak

Gynecology_Novak. The most common acid-base disorder encountered in the postoperative period is alkalosis (27). Alkalosis is usually of no clinical significance and resolves spontaneously. Several etiologic factors may include hyperventilation associated with pain; posttraumatic transient hyperaldosteronism, which results in decreased renal bicarbonate excretion; nasogastric suction, which removes hydrogen ions; infusion of bicarbonate during blood transfusions in the form of citrate, which is converted to bicarbonates; administration of exogenous alkali; and use of diuretics. Alkalosis can be corrected with removal of the inciting cause and the correction of extracellular ﬂuid and potassium deficits (Table 22.3). Full correction usually can be safely achieved over 1 to 2 days.


Gynecology_Novak

Gynecology_Novak. Marked alkalosis, with serum pH higher than 7.55, can result in serious cardiac arrhythmias or central nervous system seizures. Myocardial excitability is particularly pronounced with concurrent hypokalemia. Under such conditions, ﬂuid and electrolyte replacement may not Table 22.3 Causes of Metabolic Alkalosis Disorder Source of Alkali Cause of Renal HCO Retention Nasogastric suction Gastric mucosa ↓↓ECF, ↓K Diuretics Renal epithelium ↓ECF, ↓K Respiratory acidosis ↓ECF, ↓K, ↑PCO2 and diuretics Exogenous base NaHCO3,Na Coexisting disorder of ECF, citrate, Na lactate K, PaCO2 ↓ECF, extracellular ﬂuid depletion; ↓K, potassium depletion; ↑↑PCO2, carbon dioxide retention; NaHCO3, sodium bicarbonate; PaCO2, partial pressure of carbon dioxide, arterial.


Gynecology_Novak

Gynecology_Novak. be sufficient to correct the alkalosis rapidly. Acetazolamide (250 to 500 mg) can be given orally or intravenously two to four times daily to induce renal bicarbonate diuresis. Treatment with an acidifying agent rarely is necessary and should be reserved for acutely symptomatic patients (i.e., those with cardiac or central nervous system dysfunction) or for patients with advanced renal disease. Under such conditions, hydrogen chloride (5 to 10 mEq per hour of a 100-mmol solution) can be given via a central intravenous line. Ammonium chloride can be given orally or intravenously but should not be given to patients with hepatic disease.


Gynecology_Novak

Gynecology_Novak. Metabolic acidosis is less common than alkalosis during the postoperative period, but acidosis can be serious because of its effect on the cardiovascular system. Under conditions of acidosis, there are decreased myocardial contractility, a propensity for vasodilation of the peripheral vasculature leading to hypotension, and refractoriness of the fibrillating heart to defibrillation (27). These effects promote decompensation of the cardiovascular system and can hinder attempts at resuscitation. Metabolic acidosis results from a decrease in serum bicarbonate levels caused by the consumption and replacement of bicarbonate by circulating acids or the replacement by other anions such as chloride. The proper workup includes a measurement of the anion gap: Anion gap = (Na++ K+) − (CI− + HCO3 −) = 10 to 14 mEq/L (normal) The anion gap is composed of circulating protein, sulfate, phosphate, citrate, and lactate (36).


Gynecology_Novak

Gynecology_Novak. With metabolic acidosis, the anion gap can be increased or normal. An increase in circulating acids will consume and replace bicarbonate ion, increasing the anion gap. The causes include an increase in circulating lactic acid secondary to anaerobic glycolysis, such as that seen under conditions of poor tissue perfusion; increased ketoacids, as with cases of severe diabetes or starvation; exogenous toxins; and renal dysfunction, which leads to increased circulating sulfates and phosphates (37). The diagnosis can be established via a thorough history and measurement of serum lactate (normal <2 mmol/L), serum glucose, and renal function parameters. Metabolic acidosis in the face of a normal anion gap is usually the result of an imbalance of the ions chloride and bicarbonate, which occurs under conditions leading to excess chloride and decreased bicarbonate. Hyperchloremic acidosis can be seen in patients who underwent saline loading. Bicarbonate loss will be seen in patients with small


Gynecology_Novak

Gynecology_Novak. conditions leading to excess chloride and decreased bicarbonate. Hyperchloremic acidosis can be seen in patients who underwent saline loading. Bicarbonate loss will be seen in patients with small bowel fistulas, new ileostomies, severe diarrhea, or renal tubular acidosis. In patients with marked extracellular volume expansion, which often occurs postoperatively, the relative decrease in serum sodium and bicarbonate will result in a mild acidosis. A summary of the various causes of metabolic acidosis is shown in Table 22.4.


Gynecology_Novak

Gynecology_Novak. The treatment of metabolic acidosis depends on the cause. In patients with lactic acidosis, restoration of tissue perfusion is imperative. This state can be accomplished through cardiovascular and pulmonary support as needed, oxygen therapy, and aggressive treatment of systemic Table 22.4 Causes of Metabolic Acidosis Adapted from Narins RG, Lazarus MJ. Renal system. In: Vandam LD, ed. To make the patient ready for anesthesia: medical care of the surgical patient, 2nd ed. Menlo Park, CA: Addison Wesley, 1984:67–114. Table 22.5 Acid-Base Disorders and Their Treatment NaHCl, sodium hydrochloride.


Gynecology_Novak

Gynecology_Novak. Table 22.5 Acid-Base Disorders and Their Treatment NaHCl, sodium hydrochloride. infection wherever appropriate. Ketosis from diabetes can be corrected gradually with insulin therapy. Ketosis resulting from chronic starvation or from lack of caloric support postoperatively can be corrected with nutrition. In patients with normal anion gap acidosis, bicarbonate lost from the gastrointestinal tract should be replaced, excess chloride administration can be curtailed, and, where necessary, a loop diuretic can be used to induce renal clearance of chloride. Dilutional acidosis can be corrected with mild ﬂuid restriction.


Gynecology_Novak

Gynecology_Novak. Bicarbonates should not be given unless serum pH is lower than 7.2 or severe cardiac complications secondary to acidosis are present. Close monitoring of serum potassium levels is mandatory. Under states of acidosis, potassium will exit the cell and enter the circulation. The patient with a normal potassium concentration and metabolic acidosis is actually depleted of intracellular potassium. Treatment of the acidosis without potassium replacement will result in severe hypokalemia with its associated risks. A summary of the various acid-base abnormalities and associated therapies is shown in Table 22.5.


Gynecology_Novak

Gynecology_Novak. Although satisfactory analgesia is easily achievable with available methods, patients continue to suffer unnecessarily from postoperative pain. Studies consistently show that 25% to 50% of patients suffer moderate to severe pain in the postoperative period (38,39). There are several reasons for the existing inadequacies in pain management. First, patient expectations of pain relief are low and they are not aware of the extent of analgesia that they should expect. In a study of the perception of pain relief after surgery, 86% of patients had moderate to severe pain after surgery, but 70% felt that the pain was as severe as they expected (40). Second, there is a lack of formal physician training in pain management. This lack is epitomized by the commonly written order prescribing a range of narcotic to be given intramuscularly every 3 to 4 hours as needed, leaving pain management decisions to the nursing staff, with no attempt made to titrate the dose of the prescribed narcotic


Gynecology_Novak

Gynecology_Novak. range of narcotic to be given intramuscularly every 3 to 4 hours as needed, leaving pain management decisions to the nursing staff, with no attempt made to titrate the dose of the prescribed narcotic commensurate with individual patient requirements. Third, attitudes continue to be inﬂuenced by the common misconception that the use of narcotics in the postoperative period results in opioid dependence. In one review, 20% of nurses responding to a staff questionnaire expressed concern that the use of opioid analgesics during the postoperative period could cause addiction (40). Studies confirm that nurses administer less than one-fourth of the total dose of narcotic that is prescribed on an as-needed basis. To facilitate acute pain management and reduce the number of adverse outcomes, the American Society of Anesthesiologists established practice guidelines for acute pain management in the perioperative setting (41).


Gynecology_Novak

Gynecology_Novak. The minimal effective analgesic concentration (MEAC) refers to the serum concentration of a drug below which very little analgesia is achieved. At the MEAC, receptor and plasma concentrations of a drug are in equilibrium. Steady-state drug concentrations above the MEAC are difficult to achieve with intramuscular depot injection (42). In one study, patients receiving intramuscular injections with meperidine hydrochloride (Demerol) every 4 hours experienced marked intrapatient and interpatient variations in narcotic drug peak concentrations and in the time required to reach these peaks. As a result, serum concentrations of drug were above the MEAC an average of only 35% of each 4-hour dosing interval (43). Variable pain control following intermittent intramuscular injections is the result of inadequate, highly variable, and unpredictable blood concentrations (44). Adequate analgesia can be achieved through intramuscular or subcutaneous modes of administration, but unpredictable


Gynecology_Novak

Gynecology_Novak. result of inadequate, highly variable, and unpredictable blood concentrations (44). Adequate analgesia can be achieved through intramuscular or subcutaneous modes of administration, but unpredictable absorption can make titration difficult. Small intravenous boluses can be more easily titrated but may be shorter acting, requiring more frequent injections and thus intensive nursing care, whereas larger intravenous boluses may be associated with a higher incidence of central nervous system and respiratory depression.


Gynecology_Novak

Gynecology_Novak. The patient-controlled analgesia (PCA) technique, which allows patients to self-administer small doses of narcotic on demand, allows titration of measured boluses of narcotic as needed to relieve pain. This technique can provide a more thorough analgesia with maintenance of steady-state drug concentrations above the MEAC.


Gynecology_Novak

Gynecology_Novak. Irrespective of the route of administration, analgesics must be front loaded to provide prompt analgesia from the start. Without front loading, attainment of the MEAC will not occur for at least three elimination half-lives of the narcotic agent that is used. After front loading, additional small boluses of narcotic can be administered until analgesia is achieved. From the total dose of drug required to achieve analgesia, maintenance drug dosages can then be determined and administered either as a continuous infusion or on a scheduled basis, so that the dose of drug administered offsets the amount that is cleared. Thereafter, prescribed doses of narcotic can be adjusted as needed.


Gynecology_Novak

Gynecology_Novak. Devices for administering PCA are electronically controlled infusion pumps that deliver a preset dose of narcotic into a patient’s indwelling intravenous catheter upon patient request. The devices all contain delay intervals or lockout times during which patient demands for more narcotic are not met. These devices eliminate the delay between the onset of pain and the administration of analgesic agents, a common problem inherent with on-demand analgesic orders in busy hospital wards. Patient-controlled analgesia has excellent patient acceptance. Compared with conventional intramuscular injections, serum narcotic levels have significantly lower variability in patients using PCA (42). Patients using PCA have improved analgesia, a lower incidence of postoperative pulmonary complications, and less confusion than those given intramuscular narcotics (45). The total dose of narcotic used is lower with PCA than with conventional intramuscular depot injection.


Gynecology_Novak

Gynecology_Novak. The use of PCA does not eliminate the adverse side effects of narcotics. Potentially life-threatening respiratory depression is seen in as many as 0.5% of patients using PCA. The use of a continuous narcotic infusion in addition to demand dosing is associated with a fourfold increase in respiratory depression. Elderly patients and those with preexisting respiratory compromise are at risk for respiratory depression (42). Carefully supervised regimens using continuous infusions, on-demand intramuscular therapy, or fixed dosage schedules (every 4-hour dosing) with on-demand supplementation can have analgesic efficacy comparable with PCA. The type of close supervision required to achieve adequate on-demand analgesia without PCA is difficult to maintain. Use of PCA shortens the time between the onset of pain and the administration of pain medication, provides more continuous access to analgesics, and allows for an overall steadier state of pain control.


Gynecology_Novak

Gynecology_Novak. Anesthetics and narcotics administered either in the epidural space or intrathecally are among the most potent analgesic agents available; the efficacy of these agents is greater than that provided by intravenous PCA techniques. These drugs can be administered in several ways, including a single-shot dose given by epidural or intrathecal injection, intermittent injection given either on schedule or on demand, and continuous infusion.


Gynecology_Novak

Gynecology_Novak. Because of the risk of central nervous system infections and headaches, intrathecal administration is usually limited to a single dose of narcotic, local anesthetic, or both. In comparison with epidural administration, duration of action for a single dose is increased via the intrathecal route as a result of the high concentrations of drug attained in the cerebrospinal ﬂuid. The risk of central nervous system and respiratory depression, and systemic hypotension, is increased. The low doses of opioids required for intrathecal analgesia are sufficient to be associated with an increased risk of respiratory depression (46). Some investigators warn against the use of intrathecal spinal analgesia outside the intensive care setting.


Gynecology_Novak

Gynecology_Novak. Epidural administration is the preferred approach and provides extended (>24 hours) pain control during the postoperative period. Relative contraindications are the presence of coagulopathy, sepsis, and hypotension. Both anesthetic and narcotic agents are used with excellent efficacy. Among the anesthetic agents, bupivacaine is the most popular, providing excellent analgesia with minimal toxicity. Epidural analgesia is most suited for pain control in the lower abdomen and extremities. Potential adverse effects of epidural anesthetic agents include urinary retention, motor weakness, hypotension, and central nervous system and cardiac depression. In contrast to anesthetic agents, opioids offer excellent analgesia without accompanying sympathetic blockade. Epidural opioids tend to have a much longer duration of action, and hypotension is a rare complication. Compared with epidural anesthetics, there is a higher incidence of nausea and vomiting, respiratory depression, and pruritus (47).


Gynecology_Novak

Gynecology_Novak. Compared with analgesics administered intramuscularly or intravenously, epidural analgesia is associated with improved pulmonary function postoperatively, a lower incidence of pulmonary complications, a decrease in postoperative venous thromboembolic complications (most likely secondary to earlier ambulation), fewer gastrointestinal side effects, a lower incidence of central nervous system depression, and shorter convalescence (47). A systematic review concluded that continuous epidural anesthesia is more effective than intravenous opioid PCA in reducing postoperative pain for up to 72 hours after abdominal surgery (48). Severe respiratory depression, which occurs in less than 1% of patients, is the most serious potential complication. A lower incidence of respiratory depression occurs with the more lipophilic drugs such as fentanyl, which is quickly absorbed within the spinal cord and is less likely to diffuse to the central nervous system respiratory control centers. Pruritus,


Gynecology_Novak

Gynecology_Novak. with the more lipophilic drugs such as fentanyl, which is quickly absorbed within the spinal cord and is less likely to diffuse to the central nervous system respiratory control centers. Pruritus, nausea, and urinary retention are common but can be managed easily and usually are of little clinical significance. Cost is perhaps the main and most limiting drawback of epidural analgesia.


Gynecology_Novak

Gynecology_Novak. Close monitoring by nursing staff is required for safe administration of epidural analgesia. An intensive care setting is not necessary. Epidural analgesics can be administered safely in a hospital ward setting under close nursing supervision, using respiratory monitoring with hourly ventilatory checks during the first 8 hours of epidural analgesia.


Gynecology_Novak

Gynecology_Novak. Current therapeutic strategies for perioperative pain control are largely dependent on multimodal therapy with opioid analgesics and nonsteroidal anti-inﬂammatory drugs (NSAIDs). The nonselective NSAID ketorolac is a potent drug that can be given orally or parenterally. Ketorolac has a slightly slower onset of activity than fentanyl but has an analgesic potency comparable to morphine. The theoretical advantages of NSAIDs over opioids include absence of respiratory depression, lack of abuse potential, decreased sedative effects, decreased nausea, early return of bowel function, and faster recovery. In clinical studies, ketorolac is found to have analgesic effects similar to those of morphine in postoperative orthopedic patients and, when used in conjunction with PCA, significantly reduced opioid requirements (49,50). Depending on the type of surgery, ketorolac has an opioid dose-sparing effect of a mean of 36% and improves analgesic control of moderate to severe pain 24 hours


Gynecology_Novak

Gynecology_Novak. reduced opioid requirements (49,50). Depending on the type of surgery, ketorolac has an opioid dose-sparing effect of a mean of 36% and improves analgesic control of moderate to severe pain 24 hours postoperatively (51). In the obstetric population, intravenous ketorolac is effective in reducing postoperative narcotic use after cesarean delivery (52). Although the U.S. Food and Drug Administration has not approved ketorolac for use during lactation, it was quantified in breast milk and has lower levels than ibuprofen (53).


Gynecology_Novak

Gynecology_Novak. Potential adverse effects associated with the use of NSAIDs include an increased risk of renal compromise (particularly in patients suffering from acute hypovolemia), gastrointestinal side effects, hypersensitivity reactions, and bleeding. The effects of ketorolac on bleeding are inconsistent. Studies of ketorolac on healthy volunteers showed transient increases in bleeding time and decreases in platelet aggregation, but these changes were not clinically significant (54). A retrospective cohort study showed increased risk of gastrointestinal and operative site bleeding in elderly patients receiving high doses of ketorolac, between 105 and 120 mg per day. Increased risk for all gastrointestinal bleeding was associated with use of ketorolac for more than 5 days (55). Controlled prospective studies did not show a significant increase in blood loss in patients who receive NSAIDs perioperatively. Ketorolac may be associated with elevated rates of acute renal failure when therapy exceeds 5


Gynecology_Novak

Gynecology_Novak. studies did not show a significant increase in blood loss in patients who receive NSAIDs perioperatively. Ketorolac may be associated with elevated rates of acute renal failure when therapy exceeds 5 days (56). A meta-analyses of the use of postoperative NSAIDs in patients with normal preoperative renal function showed a clinically insignificant reduction in renal function (57). These agents should be used with extreme care, if at all, in patients with asthma, because 5% to 10% of adult patients with asthma are sensitive to aspirin and other NSAID preparations.


Gynecology_Novak

Gynecology_Novak. With the advantages of less gastrointestinal toxicity and a lack of antiplatelet effects, selective cyclooxygenase-2 (COX-2) inhibitors are a valuable option in perioperative pain management (58). Although evidence exists showing an increased risk of serious cardiovascular events associated with COX-2 inhibitors, short-term use of these agents in the perioperative setting can be considered in low-risk patients without existing cardiovascular disease (59–64).


Gynecology_Novak

Gynecology_Novak. In addition to NSAIDs, other adjuvant analgesics are being explored to minimize opioid use and the accompanying side effects, which can delay recovery. Capsaicin is a nonnarcotic that promotes release of substance P, a neurotransmitter for pain and heat, which initially results in a burning sensation, but eventually leads to substance P depletion and a reduction in pain. It is available in both topical and injectable preparations. Ketamine blocks centrally located N-methyld-aspartate pain receptors, and at low subanesthetic doses can reduce central sensitization caused by surgery and prevent opioid-induced hyperalgesia. At higher doses, ketamine is associated with hallucinations, dizziness, nausea, and vomiting. Gabapentin and pregabalin are nonnarcotics that prevent the release of excitatory neurotransmitters that relay pain signals. They reduce opioid requirements and are effective antihyperalgesic agents (64).


Gynecology_Novak

Gynecology_Novak. Gynecologic procedures often involve breaching the reproductive and gastrointestinal tracts, which harbor endogenous bacteria capable of causing polymicrobial infections in the postoperative period (Table 22.6). Despite great advances in aseptic technique and drug development, bacterial contamination of the operative site and postoperative infections are an inevitable part of the practice of gynecologic surgery. Prevention of these surgical complications includes Table 22.6 Bacteria Indigenous to the Lower Genital Tract Lactobacillus Enterobacter agglomerans Diphtheroids Klebsiella pneumoniae Staphylococcus aureus Proteus mirabilis Staphylococcus epidermidis Proteus vulgaris Streptococcus agalactiae Morganella morganii Streptococcus faecalis Citrobacter diversus α-Hemolytic streptococci Bacteroides species Group D streptococci B. disiens Peptostreptococci B. fragilis Peptococcus B. melaninogenicus Clostridium Gaffky anaerobia Escherichia coli Fusobacterium Enterobacter cloacae