Surgery_Schwartz

Surgery_Schwartz. YH, Lee JH, Song HG, Byon HJ, Kim HS, Kim JT. The accuracy of noninvasive hemoglobin monitoring using the radical-7 pulse CO-Oximeter in children undergoing neurosur-gery. Anesth Analg. 2012;115(6):1302-1307. 65. Suehiro K, Joosten A, Alexander B, Cannesson M. Continu-ous noninvasive hemoglobin monitoring: ready for prime time? Curr Opin Crit Care. 2015;21(3):265-270. 66. Jubran A, Tobin MJ. Monitoring during mechanical ventilation. Clin Chest Med. 1996;17(3):453-473. 67. Sugrue M. Abdominal compartment syndrome. Curr Opin Crit Care. 2005;11(4):333-338. 68. Ivatury RR, Porter JM, Simon RJ, Islam S, John R, Stahl WM. Intra-abdominal hypertension after life-threatening penetrat-ing abdominal trauma: prophylaxis, incidence, and clinical relevance to gastric mucosal pH and abdominal compartment syndrome. J Trauma. 1998;44(6):1016-1021; discussion 21-23. 69. Kirkpatrick AW, Roberts DJ, De Waele J, et al. Intra-abdominal hypertension and the abdominal compartment syndrome: updated consensus


Surgery_Schwartz

Surgery_Schwartz. syndrome. J Trauma. 1998;44(6):1016-1021; discussion 21-23. 69. Kirkpatrick AW, Roberts DJ, De Waele J, et al. Intra-abdominal hypertension and the abdominal compartment syndrome: updated consensus definitions and clinical practice guidelines from the World Society of the Abdominal Compartment Syndrome. Intens Care Med. 2013;39(7):1190-1206. 70. Brain Trauma Foundation; American Association of Neurological Surgeons; Congress of Neurological Surgeons, et al. Guidelines for the management of severe traumatic brain injury. VI. Indications for intracranial pressure monitoring. J Neurotrauma. 2007;24(suppl 1):S37-S44. 71. Brain Trauma Foundation; American Association of Neurologi-cal Surgeons; Congress of Neurological Surgeons, et al. Guide-lines for the management of severe traumatic brain injury. VII. Intracranial pressure monitoring technology. J Neurotrauma. 2007;24(suppl 1):S45-S54. 72. Juul N, Morris GF, Marshall SB, Marshall LF. Intracranial hypertension and cerebral perfusion


Surgery_Schwartz

Surgery_Schwartz. injury. VII. Intracranial pressure monitoring technology. J Neurotrauma. 2007;24(suppl 1):S45-S54. 72. Juul N, Morris GF, Marshall SB, Marshall LF. Intracranial hypertension and cerebral perfusion pressure: influence on neurological deterioration and outcome in severe head injury. The Executive Committee of the International Selfotel Trial. J Neurosurg. 2000;92(1):1-6. 73. Eisenberg HM, Frankowski RF, Contant CF, Marshall LF, Walker MD. High-dose barbiturate control of elevated intracra-nial pressure in patients with severe head injury. J Neurosurg. 1988;69(1):15-23. 74. Brain Trauma Foundation; American Association of Neuro-logical Surgeons; Congress of Neurological Surgeons, et al. Guidelines for the management of severe traumatic brain injury. IX. Cerebral perfusion thresholds. J Neurotrauma. 2007;24(suppl 1):S59-S64. 75. Cremer OL, van Dijk GW, van Wensen E, et al. Effect of intra-cranial pressure monitoring and targeted intensive care on functional outcome after severe head


Surgery_Schwartz

Surgery_Schwartz. Neurotrauma. 2007;24(suppl 1):S59-S64. 75. Cremer OL, van Dijk GW, van Wensen E, et al. Effect of intra-cranial pressure monitoring and targeted intensive care on functional outcome after severe head injury. Crit Care Med. 2005;33(10):2207-2213. 76. Sigl JC, Chamoun NG. An introduction to bispectral analysis for the electroencephalogram. J Clin Monit. 1994;10(6):392-404. 77. Gan TJ, Glass PS, Windsor A, et al. Bispectral index monitoring allows faster emergence and improved recovery from propo-fol, alfentanil, and nitrous oxide anesthesia. BIS Utility Study Group. Anesthesiology. 1997;87(4):808-815. 78. Simmons LE, Riker RR, Prato BS, Fraser GL. Assessing seda-tion during intensive care unit mechanical ventilation with the Bispectral Index and the Sedation-Agitation Scale. Crit Care Med. 1999;27(8):1499-1504. 79. Qureshi AI, Sung GY, Razumovsky AY, Lane K, Straw RN, Ulatowski JA. Early identification of patients at risk for symp-tomatic vasospasm after aneurysmal subarachnoid


Surgery_Schwartz

Surgery_Schwartz. Med. 1999;27(8):1499-1504. 79. Qureshi AI, Sung GY, Razumovsky AY, Lane K, Straw RN, Ulatowski JA. Early identification of patients at risk for symp-tomatic vasospasm after aneurysmal subarachnoid hemorrhage. Crit Care Med. 2000;28(4):984-990. 80. Czosnyka M, Matta BF, Smielewski P, Kirkpatrick PJ, Pickard JD. Cerebral perfusion pressure in head-injured patients: a noninvasive assessment using transcranial Doppler ultrasonography. J Neurosurg. 1998;88(5):802-808. 81. Feldman Z, Robertson CS. Monitoring of cerebral hemody-namics with jugular bulb catheters. Crit Care Clin. 1997;13(1): 51-77. 82. Vigue B, Ract C, Benayed M, et al. Early SjvO2 monitoring in patients with severe brain trauma. Intensive Care Med. 1999;25(5):445-451. 83. Murkin JM, Arango M. Near-infrared spectroscopy as an index of brain and tissue oxygenation. Br J Anaesth. 2009;103(suppl 1):i3-i13. 84. Peters J, Van Wageningen B, Hoogerwerf N, Tan E. Near-infrared spectroscopy: a promising prehospital tool for


Surgery_Schwartz

Surgery_Schwartz. as an index of brain and tissue oxygenation. Br J Anaesth. 2009;103(suppl 1):i3-i13. 84. Peters J, Van Wageningen B, Hoogerwerf N, Tan E. Near-infrared spectroscopy: a promising prehospital tool for man-agement of traumatic brain injury. Prehosp Disaster Med. 2017;32(4):414-418. 85. Schober P, Bossers SM, Schwarte LA. Intracranial hematoma detection by near infrared spectroscopy in a helicopter emer-gency medical service: practical experience. Biomed Res Int. 2017;2017:1846830. 86. Stiefel MF, Spiotta A, Gracias VH, et al. Reduced mortality rate in patients with severe traumatic brain injury treated with brain tissue oxygen monitoring. J Neurosurg. 2005;103(5):805-811.Brunicardi_Ch13_p0433-p0452.indd 45122/02/19 2:21 PM


Surgery_Schwartz

Surgery_Schwartz. Brunicardi_Ch13_p0433-p0452.indd 45222/02/19 2:21 PMThis page intentionally left blank


Surgery_Schwartz

Surgery_Schwartz. Minimally Invasive Surgery, Robotics, Natural Orifice Transluminal Endoscopic Surgery, and Single-Incision Laparoscopic SurgeryDonn H. Spight, Blair A. Jobe, and John G. Hunter 14chapterINTRODUCTIONMinimally invasive surgery describes an area of surgery that crosses all traditional disciplines, from general surgery to neu-rosurgery. It is not a discipline unto itself, but more a philosophy of surgery, a way of thinking. Minimally invasive surgery is a means of performing major operations through small inci-sions, often using miniaturized, high-tech imaging sys-tems, to minimize the trauma of surgical exposure. Some believe that the term minimal access surgery more accurately describes the small incisions generally necessary to gain access to surgical sites in high-tech surgery, but John Wickham’s term minimally invasive surgery (MIS) is widely used because it describes the paradox of postmodern high-tech surgery—small holes, big operations.Robotic surgery today is practiced using a


Surgery_Schwartz

Surgery_Schwartz. Wickham’s term minimally invasive surgery (MIS) is widely used because it describes the paradox of postmodern high-tech surgery—small holes, big operations.Robotic surgery today is practiced using a single platform (Intuitive, Inc, Sunnyvale, CA) and should better be termed computer-enhanced surgery because the term robotics assumes autonomous action that is not a feature of the da Vinci robotic system. Instead, the da Vinci robot couples an ergonomic work-station that features stereoptic video imaging and intuitive micromanipulators (surgeon side) with a set of arms deliver-ing specialized laparoscopic instruments enhanced with more degrees of freedom than are allowed by laparoscopic surgery alone (patient side). A computer between the surgeon side and patient side removes surgical tremor and scales motion to allow 1precise microsurgery, which is helpful for microdissection and difficult anastomoses.Single-incision laparoscopic surgery (SILS), also called laparoendoscopic single-site


Surgery_Schwartz

Surgery_Schwartz. and scales motion to allow 1precise microsurgery, which is helpful for microdissection and difficult anastomoses.Single-incision laparoscopic surgery (SILS), also called laparoendoscopic single-site surgery (LESS), is a recent addi-tion to the armamentarium of the minimally invasive surgeon. As public awareness has grown, so too has its spread outside of larger institutions. SILS challenges the well-established paradigm of standard laparoscopic surgery by placing multiple trocars within the fascia at the umbilicus or through a single multichannel trocar at the umbilicus. The manipulation of tightly spaced instruments across the fulcrum of the abdomi-nal wall requires that the surgeon either operate in a crossed hands fashion or use specialized curved instruments to avoid clashing outside the body while working intra-abdominally. The primary advantage of SILS is the reduction to one surgical scar. Greater efficacy, safety, and cost savings have yet to be fully elucidated in the


Surgery_Schwartz

Surgery_Schwartz. the body while working intra-abdominally. The primary advantage of SILS is the reduction to one surgical scar. Greater efficacy, safety, and cost savings have yet to be fully elucidated in the increasing number of procedures that are being attempted in this manner. The advent of a robotic SILS platform now enables the computer reassignment of the surgeon’s hands, thus eliminating the difficult ergonomic challenges making the technique far more accessible.Natural orifice transluminal endoscopic surgery (NOTES) is an extension of interventional endoscopy. Using the mouth, anus, vagina, and urethra (natural orifices), flexible endoscopes are passed through the wall of the esophagus, stomach, colon, Introduction 453Historical Background 454Physiology and Pathophysiology of Minimally Invasive Surgery 455Laparoscopy / 455Thoracoscopy / 457Extracavitary Minimally Invasive Surgery / 457Anesthesia / 457The Minimally Invasive Team / 458Room Setup and the Minimally Invasive Suite /


Surgery_Schwartz

Surgery_Schwartz. Invasive Surgery 455Laparoscopy / 455Thoracoscopy / 457Extracavitary Minimally Invasive Surgery / 457Anesthesia / 457The Minimally Invasive Team / 458Room Setup and the Minimally Invasive Suite / 458Patient Positioning / 458General Principles of Access / 459Laparoscopic Access / 459Access for Subcutaneous and Extraperitoneal Surgery / 460Hand-Assisted Laparoscopic Access / 461Natural Orifice Transluminal Endoscopic Surgery Access / 461Single-Incision Laparoscopic Surgery Access / 462Port Placement / 462Imaging Systems / 463Energy Sources for Endoscopic and Endoluminal Surgery / 465Instrumentation / 467Robotic Surgery / 467Endoluminal and Endovascular Surgery / 469Natural Orifice Transluminal Endoscopic Surgery / 470Single-Incision Laparoscopic Surgery / 471Special Considerations 473Pediatric Laparoscopy / 473Laparoscopy During Pregnancy / 473Minimally Invasive Surgery and Cancer Treatment / 474Considerations in the Elderly and Infirm / 474Cirrhosis and Portal Hypertension /


Surgery_Schwartz

Surgery_Schwartz. Laparoscopy / 473Laparoscopy During Pregnancy / 473Minimally Invasive Surgery and Cancer Treatment / 474Considerations in the Elderly and Infirm / 474Cirrhosis and Portal Hypertension / 474Economics of Minimally Invasive Surgery / 474Education and Skill Acquisition / 474Telementoring / 475Innovation and Introduction of New Procedures / 475Brunicardi_Ch14_p0453-p0478.indd 45301/03/19 4:58 PM 454bladder, or vagina entering the mediastinum, the pleural space, or the peritoneal cavity. The advantage of this method of mini-mal access is principally the elimination of the scar associated with laparoscopy or thoracoscopy. Other advantages have yet to be elucidated, including pain reduction, need for hospitalization, and cost savings.HISTORICAL BACKGROUNDAlthough the term minimally invasive surgery is relatively recent, the history of its component parts is nearly 100 years old. What is considered the newest and most popular variety of MIS, laparoscopy, is in fact the oldest.


Surgery_Schwartz

Surgery_Schwartz. invasive surgery is relatively recent, the history of its component parts is nearly 100 years old. What is considered the newest and most popular variety of MIS, laparoscopy, is in fact the oldest. Primitive laparos-copy, placing a cystoscope within an inflated abdomen, was first performed by Kelling in 1901.1 Illumination of the abdomen required hot elements at the tip of the scope and was danger-ous. In the late 1950s, Hopkins described the rod lens, a method of transmitting light through a solid quartz rod with no heat and little light loss.1 Around the same time, thin quartz fibers were discovered to be capable of trapping light internally and conducting it around corners, opening the field of fiber optics and allowing the rapid development of flexible endoscopes.2,3 In the 1970s, the application of flexible endoscopy grew faster than that of rigid endoscopy except in a few fields such as gyne-cology and orthopedics.4 By the mid-1970s, rigid and flexible endoscopes made a rapid


Surgery_Schwartz

Surgery_Schwartz. application of flexible endoscopy grew faster than that of rigid endoscopy except in a few fields such as gyne-cology and orthopedics.4 By the mid-1970s, rigid and flexible endoscopes made a rapid transition from diagnostic instruments to therapeutic ones. The explosion of video-assisted surgery in the past 20 years was a result of the development of compact, high-resolution, charge-coupled devices (CCDs) that could be mounted on the internal end of flexible endoscopes or on the external end of a Hopkins telescope. Coupled with bright light sources, fiber-optic cables, and high-definition video monitors, the videoendoscope has changed our understanding of surgical anatomy and reshaped surgical practice.Flexible endoscopic imaging started in the 1960s with the first bundling of many quartz fibers into bundles, one for illu-mination and one for imaging. The earliest upper endoscopes revolutionized the diagnosis and treatment of gastroesophageal reflux and peptic ulcer disease and made


Surgery_Schwartz

Surgery_Schwartz. fibers into bundles, one for illu-mination and one for imaging. The earliest upper endoscopes revolutionized the diagnosis and treatment of gastroesophageal reflux and peptic ulcer disease and made possible early detec-tion of upper and lower gastrointestinal (GI) cancer at a stage that could be cured. The first endoscopic surgical procedure was the colonoscopic polypectomy, developed by Shinya and Wolfe, two surgeons from New York City. The percutane-ous endoscopic gastrostomy (PEG) invented by Gauderer and Ponsky may have been the first NOTES procedure, reported in 1981.5 Endoscopic pancreatic pseudocyst drainage is thought to be the next NOTES procedure developed; however, there was little energy and money put into the development of NOTES until a number of gastroenterologists claimed the ability to remove the gallbladder with a flexible endoscope, using a transgastric technique. With this pronouncement, the surgical community took notice and seized the momentum for NOTES


Surgery_Schwartz

Surgery_Schwartz. claimed the ability to remove the gallbladder with a flexible endoscope, using a transgastric technique. With this pronouncement, the surgical community took notice and seized the momentum for NOTES research and development. Today most intra-abdominal NOTES procedures remain within the realm of research or incorporate a hybrid laparoscopic technique outside of highly specialized centers. Clinically the transvaginal approach has been studied the most extensively. Evaluation of 551 female patients from the German NOTES registry has shown conversion and compli-cation rates similar to conventional laparoscopic surgery for cholecystectomy and appendectomy procedures.6 Endoscopic mucosal resection (EMR) of early-stage esophageal and gastric lesions has revolutionized the management of these malignan-cies. The peroral endoscopic myotomy (POEM) procedure for achalasia is showing clinical efficacy and gaining popularity.As the race to minimize the size and increase the function-ality of


Surgery_Schwartz

Surgery_Schwartz. malignan-cies. The peroral endoscopic myotomy (POEM) procedure for achalasia is showing clinical efficacy and gaining popularity.As the race to minimize the size and increase the function-ality of laparoscopic instruments progressed, the notion of using fewer access points to accomplish the same operations resulted in the development of single-incision laparoscopic surgery (SILS), synonymously termed laparoendoscopic single-site surgery (LESS). Viewed as a progression of laparoscopic surgery, SILS has recently garnered greater enthusiasm over its transvisceral NOTES counterpart.7 Currently the single-incision technique is used regularly across a wide variety of surgical areas including general, urologic, gynecologic, colorectal, and bariatric surgery.8 Although optical imaging produced the majority of MIS pro-cedures, other (traditionally radiologic) imaging technologies allowed the development of innovative procedures in the 1970s. Fluoroscopic imaging allowed the adoption of


Surgery_Schwartz

Surgery_Schwartz. the majority of MIS pro-cedures, other (traditionally radiologic) imaging technologies allowed the development of innovative procedures in the 1970s. Fluoroscopic imaging allowed the adoption of percutaneous vas-cular procedures, the most revolutionary of which was balloon angioplasty. Balloon-based procedures spread into all fields of medicine used to open up clogged lumens with minimal access. Stents were then developed that were used in many disciplines to keep the newly ballooned segment open. The culmination of fluoroscopic balloon and stent proficiency is exemplified by the transvenous intrahepatic portosystemic shunt and by the aortic stent graft, which has nearly replaced open elective abdominal aortic aneurysm repair.MIS procedures using ultrasound imaging have been limited to fairly crude exercises, such as fragmenting kidney stones and freezing liver tumors, because of the relatively low Key Points1 Minimally invasive surgery describes a philosophical approach to surgery in


Surgery_Schwartz

Surgery_Schwartz. crude exercises, such as fragmenting kidney stones and freezing liver tumors, because of the relatively low Key Points1 Minimally invasive surgery describes a philosophical approach to surgery in which access trauma is minimized without compromising the quality of the surgical procedure.2 The carbon dioxide pneumoperitoneum used for laparoscopy induces some unique pathophysiologic consequences.3 Robotic surgery has been most valuable in the performance of minimally invasive urologic, gynecologic, colorectal, and complex abdominal wall reconstruction procedures.4 Natural orifice transluminal endoscopic surgery represents an opportunity to perform truly scar-free surgery.5 Single-incision laparoscopic surgery reduces the amount of abdominal wall trauma but presents unique challenges to the traditional tenets of laparoscopic ergonomics.6 Laparoscopy during pregnancy is best performed in the sec-ond trimester and is safe if appropriate monitoring is performed.7 Laparoscopic surgery for


Surgery_Schwartz

Surgery_Schwartz. traditional tenets of laparoscopic ergonomics.6 Laparoscopy during pregnancy is best performed in the sec-ond trimester and is safe if appropriate monitoring is performed.7 Laparoscopic surgery for cancer is also appropriate if good tissue handling techniques are maintained.8 Training for laparoscopy requires practice outside of the operating room in a simulation laboratory.Brunicardi_Ch14_p0453-p0478.indd 45401/03/19 4:58 PM 455MINIMALLY INVASIVE SURGERYCHAPTER 14resolution of ultrasound devices. Newer, high-resolution ultra-sound methods with high-frequency crystals may act as a guide while performing minimally invasive resections of individual layers of the intestinal wall.Axial imaging, such as computed tomography (CT), has allowed the development of an area of MIS that often is not recognized because it requires only a CT scanner and a long needle. CT-guided drainage of abdominal fluid collections and percutaneous biopsy of abnormal tissues are minimally invasive means of


Surgery_Schwartz

Surgery_Schwartz. not recognized because it requires only a CT scanner and a long needle. CT-guided drainage of abdominal fluid collections and percutaneous biopsy of abnormal tissues are minimally invasive means of performing procedures that previously required a celi-otomy. CT-guided percutaneous radiofrequency (RF) ablation has emerged as a useful treatment for primary and metastatic liver tumors. This procedure also is performed laparoscopically under ultrasound guidance.9A powerful, noninvasive method of imaging that will allow the development of the least invasive—and potentially noninvasive—surgery is magnetic resonance imaging (MRI). MRI is an extremely valuable diagnostic tool, but it is only slowly coming to be of therapeutic value. One obstacle to the use of MRI for MIS is that image production and refreshment of the image as a procedure progresses are slow. Another is that all instrumentation must be nonmetallic when working with the powerful magnets of an MRI scanner. Moreover, MRI


Surgery_Schwartz

Surgery_Schwartz. and refreshment of the image as a procedure progresses are slow. Another is that all instrumentation must be nonmetallic when working with the powerful magnets of an MRI scanner. Moreover, MRI magnets are bulky and limit the surgeon’s access to the patient. Open magnets have been developed that allow the surgeon to stand between two large MRI coils, obtaining access to the portion of the patient being scanned. The advantage of MRI, in addition to the superb images produced, is that there is no radiation expo-sure to patient or surgeon. Some neurosurgeons are accumu-lating experience using MRI to perform frameless stereotactic surgery.Robotic surgery has been dreamed about for some time, and many science fiction–like devices have been developed over the years to provide mechanical assistance for the surgeon. The first computer-assisted robot was designed to accurately drill femoral shaft bone for wobble-free placement of hip prostheses. Although the concept was appealing, the robot


Surgery_Schwartz

Surgery_Schwartz. for the surgeon. The first computer-assisted robot was designed to accurately drill femoral shaft bone for wobble-free placement of hip prostheses. Although the concept was appealing, the robot proved no better than a skilled orthopedic surgeon and was a good deal slower. Following this, the first and only two commercially successful robots for laparoscopic surgery were developed in California. Computer Motion, founded by Yulun Wang in Santa Barbara, used National Science Foundation funds to create a mechanical arm, the Aesop robot, which held and moved the laparoscope with voice, foot, or hand control. In Northern California, a master-slave system first developed for surgery on the multina-tional space station by Philip Green was purchased by Fred Moll and Lonnie Smith, and then reengineered with the surgeon in mind to create a remarkably intuitive computer-enhanced surgi-cal platform. The company, Intuitive Surgical, was aptly named, and their primary product, the da Vinci robot, is


Surgery_Schwartz

Surgery_Schwartz. with the surgeon in mind to create a remarkably intuitive computer-enhanced surgi-cal platform. The company, Intuitive Surgical, was aptly named, and their primary product, the da Vinci robot, is currently the only major robotic platform on the market, although competi-tors are rapidly emerging in the horizon. Although eschewed by many experienced laparoscopists, the da Vinci achieved a toehold among many skilled surgeons who found that the robot could facilitate MIS procedures that were difficult with standard laparoscopic procedures. The latest iteration of the da Vinci Xi platform released in 2014 features high-defini-tion, three-dimensional vision and a dual-console capability allowing greater visualization, assistance, and instruction capa-bilities. Additionally, the new overhead boom design facilitates anatomical access from virtually any position enabling complex multiquadrant surgeries.PHYSIOLOGY AND PATHOPHYSIOLOGY OF MINIMALLY INVASIVE SURGERYEven with the least invasive of


Surgery_Schwartz

Surgery_Schwartz. design facilitates anatomical access from virtually any position enabling complex multiquadrant surgeries.PHYSIOLOGY AND PATHOPHYSIOLOGY OF MINIMALLY INVASIVE SURGERYEven with the least invasive of the MIS procedures, physiologic changes occur. Many minimally invasive procedures require minimal or no sedation, and there are few adverse consequences to the cardiovascular, endocrinologic, or immunologic systems. The least invasive of such procedures include stereotactic biopsy of breast lesions and flexible GI endoscopy. Minimally invasive procedures that require general anesthesia have a greater physi-ologic impact because of the anesthetic agent, the incision (even if small), and the induced pneumoperitoneum.LaparoscopyThe unique feature of laparoscopic surgery is the need to lift the abdominal wall from the abdominal organs. Two methods have been devised for achieving this.10 The first, used by most sur-geons, is a pneumoperitoneum. Throughout the early 20th century, intraperitoneal


Surgery_Schwartz

Surgery_Schwartz. wall from the abdominal organs. Two methods have been devised for achieving this.10 The first, used by most sur-geons, is a pneumoperitoneum. Throughout the early 20th century, intraperitoneal visualization was achieved by inflating the abdominal cavity with air, using a sphygmomanometer bulb.11 The problem with using air insufflation is that nitrogen is poorly soluble in blood and is slowly absorbed across the peritoneal surfaces. Air pneumoperitoneum was believed to be more pain-ful than nitrous oxide (N2O) pneumoperitoneum, but less pain-ful than carbon dioxide (CO2) pneumoperitoneum. Subsequently, CO2 and N2O were used for inflating the abdomen. N2O had the advantage of being physiologically inert and rap-idly absorbed. It also provided better analgesia for laparoscopy performed under local anesthesia when compared with CO2 or air.12 Despite initial concerns that N2O would not suppress combustion, controlled clinical trials have established its safety within the peritoneal


Surgery_Schwartz

Surgery_Schwartz. under local anesthesia when compared with CO2 or air.12 Despite initial concerns that N2O would not suppress combustion, controlled clinical trials have established its safety within the peritoneal cavity.13 In addition, N2O has been shown to reduce the intraoperative end-tidal CO2 and minute ventila-tion required to maintain homeostasis when compared to CO2 pneumoperitoneum.13 The effect of N2O on tumor biology and the development of port site metastasis are unknown. As such, caution should be exercised when performing laparoscopic can-cer surgery with this agent. Finally, the safety of N2O pneumo-peritoneum in pregnancy has yet to be elucidated.The physiologic effects of CO2 pneumoperitoneum can be divided into two areas: (a) gas-specific effects and (b) pressure-specific effects (Fig. 14-1). CO2 is rapidly absorbed across the peritoneal membrane into the circulation. In the circulation, 2Local effectsPeritoneal distentionVagal reactionElevated diaphragmAltered venous


Surgery_Schwartz

Surgery_Schwartz. effects (Fig. 14-1). CO2 is rapidly absorbed across the peritoneal membrane into the circulation. In the circulation, 2Local effectsPeritoneal distentionVagal reactionElevated diaphragmAltered venous returnPainSystemic effectsHypercarbiaAcidosisIncreased afterloadIncreased catecholaminesMyocardial stressCO2Figure 14-1. Carbon dioxide gas insufflated into the peritoneal cavity has both local and systemic effects that cause a complex set of hemodynamic and metabolic alterations. (Reproduced with permission from Hunter JG: Bailliere’s Clinical Gastroen-terology Laparoscopic Surgery. London/Philadelphia: Bailliere Tindall; 1993.)Brunicardi_Ch14_p0453-p0478.indd 45501/03/19 4:58 PM 456BASIC CONSIDERATIONSPART ICO2 creates a respiratory acidosis by the generation of carbonic acid.14 Body buffers, the largest reserve of which lies in bone, absorb CO2 (up to 120 L) and minimize the development of hypercarbia or respiratory acidosis during brief endoscopic pro-cedures.14 Once the body


Surgery_Schwartz

Surgery_Schwartz. buffers, the largest reserve of which lies in bone, absorb CO2 (up to 120 L) and minimize the development of hypercarbia or respiratory acidosis during brief endoscopic pro-cedures.14 Once the body buffers are saturated, respiratory aci-dosis develops rapidly, and the respiratory system assumes the burden of keeping up with the absorption of CO2 and its release from these buffers.In patients with normal respiratory function, this is not difficult; the anesthesiologist increases the ventilatory rate or vital capacity on the ventilator. If the respiratory rate required exceeds 20 breaths per minute, there may be less efficient gas exchange and increasing hypercarbia.15 Conversely, if vital capacity is increased substantially, there is a greater opportunity for barotrauma and greater respiratory motion–induced disrup-tion of the upper abdominal operative field. In some situations, it is advisable to evacuate the pneumoperitoneum or reduce the intra-abdominal pressure to allow time for


Surgery_Schwartz

Surgery_Schwartz. motion–induced disrup-tion of the upper abdominal operative field. In some situations, it is advisable to evacuate the pneumoperitoneum or reduce the intra-abdominal pressure to allow time for the anesthesiologist to adjust for hypercarbia.16 Although mild respiratory acidosis probably is an insignificant problem, more severe respiratory acidosis leading to cardiac arrhythmias has been reported.17 Hypercarbia also causes tachycardia and increased systemic vascular resistance, which elevates blood pressure and increases myocardial oxygen demand.14,17The pressure effects of the pneumoperitoneum on cardio-vascular physiology also have been studied. In the hypovolemic individual, excessive pressure on the inferior vena cava and a reverse Trendelenburg position with loss of lower extremity muscle tone may cause decreased venous return and decreased cardiac output.14,18 This is not seen in the normovolemic patient. The most common arrhythmia created by laparoscopy is brady-cardia. A rapid


Surgery_Schwartz

Surgery_Schwartz. tone may cause decreased venous return and decreased cardiac output.14,18 This is not seen in the normovolemic patient. The most common arrhythmia created by laparoscopy is brady-cardia. A rapid stretch of the peritoneal membrane often causes a vagovagal response with bradycardia and, occasionally, hypo-tension.19 The appropriate management of this event is desuf-flation of the abdomen, administration of vagolytic agents (e.g., atropine), and adequate volume replacement.20With the increased intra-abdominal pressure compressing the inferior vena cava, there is diminished venous return from the lower extremities. This has been well documented in the patient placed in the reverse Trendelenburg position for upper abdominal operations. Venous engorgement and decreased venous return promote venous thrombosis.21,22 Many series of advanced laparoscopic procedures in which deep venous thrombosis (DVT) prophylaxis was not used demonstrate the frequency of pulmonary embolus. This usually is an


Surgery_Schwartz

Surgery_Schwartz. thrombosis.21,22 Many series of advanced laparoscopic procedures in which deep venous thrombosis (DVT) prophylaxis was not used demonstrate the frequency of pulmonary embolus. This usually is an avoidable complication with the use of sequential compression stockings, subcutaneous heparin, or low molecular weight heparin.20,23 In short-duration laparoscopic procedures, such as appendectomy, hernia repair, or cholecystectomy, the risk of DVT may not be sufficient to warrant extensive DVT prophylaxis.The increased pressure of the pneumoperitoneum is trans-mitted directly across the paralyzed diaphragm to the thoracic cavity, creating increased central venous pressure and increased filling pressures of the right and left sides of the heart. If the intra-abdominal pressures are kept under 20 mmHg, the car-diac output usually is well maintained.22-24 The direct effect of the pneumoperitoneum on increasing intrathoracic pressure increases peak inspiratory pressure, pressure across the chest


Surgery_Schwartz

Surgery_Schwartz. the car-diac output usually is well maintained.22-24 The direct effect of the pneumoperitoneum on increasing intrathoracic pressure increases peak inspiratory pressure, pressure across the chest wall, and also, the likelihood of barotrauma. Despite these concerns, disruption of blebs and consequent pneumothoraces are rare after uncomplicated laparoscopic surgery.24 Pneumo-thoraces occurring with laparoscopic esophageal surgery may be very significant. The pathophysiology and management are discussed at the end of this section. Increased intra-abdominal pressure decreases renal blood flow, glomerular filtration rate, and urine output. These effects may be mediated by direct pressure on the kidney and the renal vein.25,26 The secondary effect of decreased renal blood flow is to increase plasma renin release, thereby increasing sodium retention. Increased circu-lating antidiuretic hormone levels also are found during the pneumoperitoneum, increasing free water reabsorption in the distal


Surgery_Schwartz

Surgery_Schwartz. renin release, thereby increasing sodium retention. Increased circu-lating antidiuretic hormone levels also are found during the pneumoperitoneum, increasing free water reabsorption in the distal tubules.27 Although the effects of the pneumoperitoneum on renal blood flow are immediately reversible, the hormonally mediated changes such as elevated antidiuretic hormone levels decrease urine output for up to 1 hour after the procedure has ended. Intraoperative oliguria is common during laparoscopy, but the urine output is not a reflection of intravascular volume status; intravenous (IV) fluid administration during an uncom-plicated laparoscopic procedure should not be linked to urine output. Because insensible fluid losses through the open abdo-men are eliminated with laparoscopy, the need for supplemen-tal fluid during a laparoscopic surgical procedure should only keep up with venous pooling in the lower limbs, third-space losses into the bowel, and blood loss, which is generally less


Surgery_Schwartz

Surgery_Schwartz. for supplemen-tal fluid during a laparoscopic surgical procedure should only keep up with venous pooling in the lower limbs, third-space losses into the bowel, and blood loss, which is generally less than occurs with an equivalent open operation.The hemodynamic and metabolic consequences of pneu-moperitoneum are well tolerated by healthy individuals for a prolonged period and by most individuals for at least a short period. Difficulties can occur when a patient with compromised cardiovascular function is subjected to a long laparoscopic pro-cedure. It is during these procedures that alternative approaches should be considered or insufflation pressure reduced. Alterna-tive gases that have been suggested for laparoscopy include the inert gases helium, neon, and argon. These gases are appeal-ing because they cause no metabolic effects, but are poorly soluble in blood (unlike CO2 and N2O) and are prone to create gas emboli if the gas has direct access to the venous system.22 Gas emboli


Surgery_Schwartz

Surgery_Schwartz. because they cause no metabolic effects, but are poorly soluble in blood (unlike CO2 and N2O) and are prone to create gas emboli if the gas has direct access to the venous system.22 Gas emboli are rare but serious complications of laparoscopic surgery.23,28 They should be suspected if hypotension develops during insufflation. Diagnosis may be made by listening (with an esophageal stethoscope) for the characteristic “mill wheel” murmur. The treatment of gas embolism is to place the patient in a left lateral decubitus position with the head down to trap the gas in the apex of the right ventricle.23 A rapidly placed central venous catheter then can be used to aspirate the gas out of the right ventricle.In some situations, minimally invasive abdominal surgery can be performed without insufflation. This is possible with the assistance of an abdominal lift device that can be placed through a 10to 12-mm trocar at the umbilicus.29 These devices have the advantage of creating little


Surgery_Schwartz

Surgery_Schwartz. insufflation. This is possible with the assistance of an abdominal lift device that can be placed through a 10to 12-mm trocar at the umbilicus.29 These devices have the advantage of creating little physiologic derangement, but they are bulky and intrusive. The exposure and working room offered by lift devices also are inferior to those accomplished by pneumoperitoneum. Lifting the anterior abdominal wall reduces space available laterally and thereby displaces the bowel medi-ally and anteriorly into the operative field. A pneumoperi-toneum, with its well-distributed intra-abdominal pressure, provides better exposure. Abdominal lift devices also cause more postoperative pain, but they do allow the performance of MIS with standard (nonlaparoscopic) surgical instruments.Endocrine responses to laparoscopic surgery are not always intuitive. Serum cortisol levels after laparoscopic opera-tions are often higher than after the equivalent operation per-formed through an open incision.30 The


Surgery_Schwartz

Surgery_Schwartz. to laparoscopic surgery are not always intuitive. Serum cortisol levels after laparoscopic opera-tions are often higher than after the equivalent operation per-formed through an open incision.30 The greatest difference Brunicardi_Ch14_p0453-p0478.indd 45601/03/19 4:58 PM 457MINIMALLY INVASIVE SURGERYCHAPTER 14between the endocrine response of open and laparoscopic sur-gery is the more rapid equilibration of most stress-mediated hormone levels after laparoscopic surgery. Immune suppression also is less after laparoscopy than after open surgery. There is a trend toward more rapid normalization of cytokine levels after a laparoscopic procedure than after the equivalent procedure performed by celiotomy.31Transhiatal mobilization of the distal esophagus is com-monly performed as a component of many laparoscopic upper abdominal procedures. If there is compromise of the mediastinal pleura with resultant CO2 pneumothorax, the defect should be enlarged so as to prevent a tension


Surgery_Schwartz

Surgery_Schwartz. a component of many laparoscopic upper abdominal procedures. If there is compromise of the mediastinal pleura with resultant CO2 pneumothorax, the defect should be enlarged so as to prevent a tension pneumothorax. Even with such a strategy, tension pneumothorax may develop, as medi-astinal structures may seal the hole during inspiration, allowing the chest to fill during expiration. In addition to enlargement of the hole, a thoracostomy tube (chest tube) should be placed across the breach into the abdomen with intra-abdominal pres-sures reduced below 8 mmHg, or a standard chest tube may be placed. When a pneumothorax occurs with laparoscopic Nissen fundoplication or Heller myotomy, it is preferable to place an 18-French red rubber catheter with multiple side holes cut out of the distal end across the defect. At the end of the procedure, the distal end of the tube is pulled out a 10-mm port site (as the port is removed), and the pneumothorax is evacuated to a primitive water seal using


Surgery_Schwartz

Surgery_Schwartz. across the defect. At the end of the procedure, the distal end of the tube is pulled out a 10-mm port site (as the port is removed), and the pneumothorax is evacuated to a primitive water seal using a bowl of sterile water or saline. During laparo-scopic esophagectomy, it is preferable to leave a standard chest tube, as residual intra-abdominal fluid will tend to be siphoned through the defect postoperatively if the tube is removed at the end of the case.ThoracoscopyThe physiology of thoracic MIS (thoracoscopy) is different from that of laparoscopy. Because of the bony confines of the thorax, it is unnecessary to use positive pressure when working in the thorax.32 The disadvantages of positive pressure in the chest include decreased venous return, mediastinal shift, and the need to keep a firm seal at all trocar sites. Without positive pressure, it is necessary to place a double-lumen endotracheal tube so that the ipsilateral lung can be deflated when the opera-tion starts. By


Surgery_Schwartz

Surgery_Schwartz. keep a firm seal at all trocar sites. Without positive pressure, it is necessary to place a double-lumen endotracheal tube so that the ipsilateral lung can be deflated when the opera-tion starts. By collapsing the ipsilateral lung, working space within the thorax is obtained. Because insufflation is unneces-sary in thoracoscopic surgery, it can be beneficial to use stan-dard instruments via extended port sites in conjunction with thoracoscopic instruments. This approach is particularly useful when performing advanced procedures such as thoracoscopic anatomic pulmonary resection.Extracavitary Minimally Invasive SurgeryMany MIS procedures create working spaces in extrathoracic and extraperitoneal locations. Laparoscopic inguinal her-nia repair usually is performed in the anterior extraperitoneal Retzius space.33,34 Laparoscopic nephrectomy often is per-formed with retroperitoneal laparoscopy. Endoscopic retro-peritoneal approaches to pancreatic necrosectomy have seen some limited use.35


Surgery_Schwartz

Surgery_Schwartz. Retzius space.33,34 Laparoscopic nephrectomy often is per-formed with retroperitoneal laparoscopy. Endoscopic retro-peritoneal approaches to pancreatic necrosectomy have seen some limited use.35 Lower extremity vascular procedures and plastic surgical endoscopic procedures require the development of working space in unconventional planes, often at the level of the fascia, sometimes below the fascia, and occasionally in nonanatomic regions.36 Some of these techniques use insuffla-tion of gas, but many use balloon inflation to develop the space, followed by low-pressure gas insufflation or lift devices to maintain the space (Fig. 14-2). These techniques produce fewer and less severe adverse physiologic consequences than does the ABCFigure 14-2. Balloons are used to create extra-anatomic working spaces. In this example (A through C), a balloon is introduced into the space between the posterior rectus sheath and the rectus abdom-inal muscle. The balloon is inflated in the preperitoneal


Surgery_Schwartz

Surgery_Schwartz. spaces. In this example (A through C), a balloon is introduced into the space between the posterior rectus sheath and the rectus abdom-inal muscle. The balloon is inflated in the preperitoneal space to create working room for extraperitoneal endoscopic hernia repair.pneumoperitoneum, but the insufflation of carbon dioxide into extraperitoneal locations can spread widely, causing subcutane-ous emphysema and metabolic acidosis.AnesthesiaProper anesthesia management during laparoscopic surgery requires a thorough knowledge of the pathophysiology of the CO2 pneumoperitoneum.20 The laparoscopic surgeon can influ-ence cardiovascular performance by reducing or removing the CO2 pneumoperitoneum. Insensible fluid losses are negligible, and therefore, IV fluid administration should not exceed that necessary to maintain circulating volume. MIS procedures are often outpatient procedures, so short-acting anesthetic agents are preferable. Because the factors that require hospitaliza-tion after


Surgery_Schwartz

Surgery_Schwartz. necessary to maintain circulating volume. MIS procedures are often outpatient procedures, so short-acting anesthetic agents are preferable. Because the factors that require hospitaliza-tion after laparoscopic procedures include the management of nausea, pain, and urinary retention, the anesthesiologist should minimize the use of agents that provoke these conditions and maximize the use of medications that prevent such problems. Critical to the anesthesia management of these patients is the use of nonnarcotic analgesics (e.g., ketorolac) when hemosta-sis allows it and the liberal use of antiemetic agents, including ondansetron and steroids.The Minimally Invasive TeamFrom the beginning, the tremendous success of MIS was founded on the understanding that a team approach was Brunicardi_Ch14_p0453-p0478.indd 45701/03/19 4:58 PM 458BASIC CONSIDERATIONSPART ITable 14-1Laparoscopic surgical proceduresBASICADVANCEDAppendectomyNissen fundoplicationLymph node dissectionCholecystectomyHeller


Surgery_Schwartz

Surgery_Schwartz. 45701/03/19 4:58 PM 458BASIC CONSIDERATIONSPART ITable 14-1Laparoscopic surgical proceduresBASICADVANCEDAppendectomyNissen fundoplicationLymph node dissectionCholecystectomyHeller myotomyRoboticsInguinal hernia repairParaesophageal herniaBariatricEnteral accessGastrectomyComplex abdominal wall reconstruction Lysis of adhesionsEsophagectomy Bile duct explorationHepatectomy ColectomyPancreatectomy SplenectomyProstatectomy AdrenalectomyHysterectomy Nephrectomy Figure 14-3. An example of a typical minimally invasive surgery suite. All core equipment is located on easily movable consoles.necessary. The many laparoscopic procedures performed daily range from basic to advanced complexity, and require that the surgical team have an intimate understanding of the operative conduct (Table 14-1). Minimally invasive procedures require complicated and fragile equipment that demands constant main-tenance. In addition, multiple intraoperative adjustments to the equipment, camera, insufflator,


Surgery_Schwartz

Surgery_Schwartz. Minimally invasive procedures require complicated and fragile equipment that demands constant main-tenance. In addition, multiple intraoperative adjustments to the equipment, camera, insufflator, monitors, and patient/surgeon position are made during these procedures. As such, a coordi-nated team approach is mandated to ensure patient safety and excellent outcomes. More and more, flexible endoscopes are used to guide or provide quality control for laparoscopic pro-cedures. As NOTES, SILS, and robotic surgery become more common, hybrid procedures (laparoscopy and endoscopy) and complicated robotics cases will require a nursing staff capable of maintaining flexible endoscopes and understanding the oper-ation of sophisticated technology.A typical MIS team may consist of a laparoscopic surgeon and an operating room (OR) nurse with an interest in laparo-scopic and endoscopic surgery. Adding dedicated assistants and circulating staff with an intimate knowledge of the equipment will add to


Surgery_Schwartz

Surgery_Schwartz. and an operating room (OR) nurse with an interest in laparo-scopic and endoscopic surgery. Adding dedicated assistants and circulating staff with an intimate knowledge of the equipment will add to and enhance team competency. Studies have dem-onstrated that having a designated laparoscopic team increases the efficiency and safety of laparoscopic surgery, which is trans-lated into a benefit for the patient and the hospital.37Room Setup and the Minimally Invasive SuiteNearly all MIS, whether using fluoroscopic, ultrasound, or opti-cal imaging, incorporates a video monitor as a guide. Occasion-ally, two images are necessary to adequately guide the operation, as in procedures such as endoscopic retrograde cholangiopan-creatography, laparoscopic common bile duct exploration, and laparoscopic ultrasonography. When two images are necessary, the images should be displayed on two adjacent video monitors or projected on a single screen with a picture-in-picture effect. The video monitor(s)


Surgery_Schwartz

Surgery_Schwartz. ultrasonography. When two images are necessary, the images should be displayed on two adjacent video monitors or projected on a single screen with a picture-in-picture effect. The video monitor(s) should be set across the operating table from the surgeon. The patient should be interposed between the surgeon and the video monitor; ideally, the operative field also lies between the surgeon and the monitor. In pelviscopic sur-gery, it is best to place the video monitor at the patient’s feet, and in laparoscopic cholecystectomy, the monitor is placed at the 10 o’clock position (relative to the patient) while the surgeon stands on the patient’s left at the 4 o’clock position. The insuf-flating and patient-monitoring equipment ideally also is placed across the table from the surgeon so that the insufflating pres-sure and the patient’s vital signs and end-tidal CO2 tension can be monitored.The development of the minimally invasive surgical suite has been a tremendous contribution to the


Surgery_Schwartz

Surgery_Schwartz. the insufflating pres-sure and the patient’s vital signs and end-tidal CO2 tension can be monitored.The development of the minimally invasive surgical suite has been a tremendous contribution to the field of laparoscopy in that it has facilitated the performance of advanced proce-dures and techniques (Fig. 14-3). By having the core equipment (monitors, insufflators, and imaging equipment) located within mobile, ceiling-mounted consoles, the surgery team is able to accommodate and make small adjustments rapidly and con-tinuously throughout the procedure. The specifically designed minimally invasive surgical suite serves to decrease equipment and cable disorganization, ease the movements of operative per-sonnel around the room, improve ergonomics, and facilitate the use of advanced imaging equipment such as laparoscopic ultra-sound.38 Although having a minimally invasive surgical suite available is very useful, it is not essential to successfully carry out advanced laparoscopic


Surgery_Schwartz

Surgery_Schwartz. imaging equipment such as laparoscopic ultra-sound.38 Although having a minimally invasive surgical suite available is very useful, it is not essential to successfully carry out advanced laparoscopic procedures.Patient PositioningPatients usually are placed in the supine position for laparo-scopic surgery. When the operative field is the gastroesophageal junction or the left lobe of the liver, it is easiest to operate from between the legs. The legs may be elevated in Allen stirrups or abducted on leg boards to achieve this position. When pel-vic procedures are performed, it usually is necessary to place the legs in Allen stirrups to gain access to the perineum. A lat-eral decubitus position with the table flexed provides the best access to the retroperitoneum when performing nephrectomy or adrenalectomy. For laparoscopic splenectomy, a 45° tilt of the patient provides excellent access to the lesser sac and the lateral peritoneal attachments to the spleen. For thoracoscopic surgery,


Surgery_Schwartz

Surgery_Schwartz. or adrenalectomy. For laparoscopic splenectomy, a 45° tilt of the patient provides excellent access to the lesser sac and the lateral peritoneal attachments to the spleen. For thoracoscopic surgery, the patient is placed in the lateral position with table flexion to open the intercostal spaces and the distance between the iliac crest and costal margin (Fig. 14-4). Additional con-sideration must be made in robotic operations to position the Brunicardi_Ch14_p0453-p0478.indd 45801/03/19 4:58 PM 459MINIMALLY INVASIVE SURGERYCHAPTER 14Figure 14-4. Proper padding and protection of pressure points is an essential consideration in laparoscopic and thoracoscopic approaches. In preparation for thoracoscopy, this patient is placed in left lateral decubitus position with the table flexed, which serves to open the intercostal spaces and increase the distance between the iliac crest and the inferior costal margin.patient appropriately before starting. Clashing of the robotic arms with


Surgery_Schwartz

Surgery_Schwartz. which serves to open the intercostal spaces and increase the distance between the iliac crest and the inferior costal margin.patient appropriately before starting. Clashing of the robotic arms with surrounding equipment or each other can occur if not positioned correctly. This is more common in predecessors of the da Vinci Xi platform. Unless an operative table with inte-grated table motion is available, once the robot is docked to the patient the bed cannot be moved without undocking.When the patient’s knees are to be bent for extended peri-ods or the patient is going to be placed in a reverse Trendelen-burg position for more than a few minutes, DVT prophylaxis should be used. Sequential compression devices should be placed on the lower extremities during laparoscopic procedures to increase venous return and provides inhibition of thrombo-plastin activation.General Principles of AccessThe most natural ports of access for MIS and NOTES are the anatomic portals of entry and exit. The


Surgery_Schwartz

Surgery_Schwartz. venous return and provides inhibition of thrombo-plastin activation.General Principles of AccessThe most natural ports of access for MIS and NOTES are the anatomic portals of entry and exit. The nares, mouth, anus, vagina, and urethra are used to access the respiratory, GI, and urinary systems. The advantage of using these points of access is that no incision is required. The disadvantages lie in the long distances between the orifice and the region of interest. For NOTES procedures, the vagina may serve as point of access, entering the abdomen via the posterior cul-de-sac of the pelvis. Similarly, the peritoneal cavity may be reached through the side wall of the stomach or colon.Access to the vascular system may be accomplished under local anesthesia by cutting down and exposing the desired vessel, usually in the groin. Increasingly, vascular access is obtained with percutaneous techniques using a small incision, a needle, and a guidewire, over which are passed a variety of


Surgery_Schwartz

Surgery_Schwartz. the desired vessel, usually in the groin. Increasingly, vascular access is obtained with percutaneous techniques using a small incision, a needle, and a guidewire, over which are passed a variety of different-sized access devices. This approach, known as the Seldinger technique, is most frequently used by general sur-geons for placement of Hickman catheters, but it also is used to gain access to the arterial and venous system for performance of minimally invasive procedures. Guidewire-assisted, Seldinger-type techniques also are helpful for gaining access to the gut for procedures such as PEG, for gaining access to the biliary system through the liver, and for gaining access to the upper urinary tract.In thoracoscopic surgery, the access technique is similar to that used for placement of a chest tube. In these procedures, general anesthesia and single lung ventilation are essential. A small incision is made over the top of a rib and, under direct vision, carried down through the


Surgery_Schwartz

Surgery_Schwartz. of a chest tube. In these procedures, general anesthesia and single lung ventilation are essential. A small incision is made over the top of a rib and, under direct vision, carried down through the pleura. The lung is collapsed, and a trocar is inserted across the chest wall to allow access with a telescope. Once the lung is completely collapsed, subse-quent access may be obtained with direct puncture, viewing all entry sites through the videoendoscope. Because insufflation of the chest is unnecessary, simple ports that keep the small inci-sions open are all that is required to allow repeated access to the thorax.Laparoscopic AccessThe requirements for laparoscopy are more involved because the creation of a pneumoperitoneum requires that instruments of access (trocars) contain valves to maintain abdominal inflation.Two methods are used for establishing abdominal access during laparoscopic procedures.39,40 The first, direct puncture laparoscopy, begins with the elevation of the relaxed


Surgery_Schwartz

Surgery_Schwartz. abdominal inflation.Two methods are used for establishing abdominal access during laparoscopic procedures.39,40 The first, direct puncture laparoscopy, begins with the elevation of the relaxed abdominal wall with two towel clips or a well-placed hand. A small inci-sion is made in the umbilicus, and a specialized spring-loaded (Veress) needle is placed in the abdominal cavity (Fig. 14-5). Figure 14-5. A. Tip of spring loaded (Veress) needle. B. Veress needle held at its serrated collar with a thumb and forefinger. At the umbilicus, the abdominal wall is grasped with fingers or penetrating towel clip to elevate the abdominal wall away from the underlying structures.ABBrunicardi_Ch14_p0453-p0478.indd 45901/03/19 4:58 PM 460BASIC CONSIDERATIONSPART IFigure 14-6. It is essential to be able to interpret the insufflator pressure readings and flow rates. These readings indicate proper intraperitoneal placement of the Veress needle.Figure 14-7. The open laparoscopy technique involves


Surgery_Schwartz

Surgery_Schwartz. able to interpret the insufflator pressure readings and flow rates. These readings indicate proper intraperitoneal placement of the Veress needle.Figure 14-7. The open laparoscopy technique involves identifica-tion and incision of the peritoneum, followed by the placement of a specialized trocar with a conical sleeve to maintain a gas seal. Spe-cialized wings on the trocar are attached to sutures placed through the fascia to prevent loss of the gas seal.With the Veress needle, two distinct pops are felt as the surgeon passes the needle through the abdominal wall fascia and the peritoneum. The umbilicus usually is selected as the preferred point of access because, in this location, the abdominal wall is quite thin, even in obese patients. The abdomen is inflated with a pressure-limited insufflator. CO2 gas usually is used, with maximal pressures in the range of 14 to 15 mmHg. During the process of insufflation, it is essential that the surgeon observe the pressure and flow readings on


Surgery_Schwartz

Surgery_Schwartz. CO2 gas usually is used, with maximal pressures in the range of 14 to 15 mmHg. During the process of insufflation, it is essential that the surgeon observe the pressure and flow readings on the monitor to confirm an intraperitoneal location of the Veress needle tip (Fig. 14-6). Laparoscopic surgery can be performed under local anesthesia, but general anesthesia is preferable. Under local anesthesia, N2O is used as the insufflating agent, and insufflation is stopped after 2 L of gas is insufflated or when a pressure of 10 mmHg is reached.After peritoneal insufflation, direct access to the abdomen is obtained with a 5or 10-mm trocar. This can be performed through a radially dilating sheath placed over the Veress needle or an optical viewing trocar. In the latter technique, a camera is placed inside of a clear pyramidal trocar. Direct puncture entry is observed as the trocar is passed through the abdominal wall. The critical issues for safe direct-puncture laparoscopy include the use of


Surgery_Schwartz

Surgery_Schwartz. inside of a clear pyramidal trocar. Direct puncture entry is observed as the trocar is passed through the abdominal wall. The critical issues for safe direct-puncture laparoscopy include the use of a vented stylet for the trocar, or a trocar with a safety shield or dilating tip. An optical viewing trocar can be used without prior insufflation; however, proper recognition of the abdominal wall layers is critical to avoid entry into the mes-entery or underlying structures. In all direct puncture entry the trocar must be pointed away from the sacral promontory and the great vessels.41 Patient position should be surveyed before trocar placement to ensure a proper trajectory.Occasionally, the direct peritoneal access (Hasson) tech-nique is advisable.42 With this technique, the surgeon makes a small incision just below the umbilicus and under direct vision locates the abdominal fascia. Two Kocher clamps are placed on the fascia, and with curved Mayo scissors, a small incision is made


Surgery_Schwartz

Surgery_Schwartz. a small incision just below the umbilicus and under direct vision locates the abdominal fascia. Two Kocher clamps are placed on the fascia, and with curved Mayo scissors, a small incision is made through the fascia and underlying peritoneum. A fin-ger is placed into the abdomen to make sure that there is no adherent bowel. A sturdy suture is placed on each side of the fascia and secured to the wings of a specialized trocar, which is then passed directly into the abdominal cavity (Fig. 14-7). Rapid insufflation can make up for some of the time lost with the initial dissection. This technique is preferable for the abdo-men of patients who have undergone previous operations in which small bowel may be adherent to the undersurface of the abdominal wound. The close adherence of bowel to the perito-neum in the previously operated abdomen does not eliminate the possibility of intestinal injury but should make great vessel injury extremely unlikely. Because of the difficulties in visual-izing


Surgery_Schwartz

Surgery_Schwartz. in the previously operated abdomen does not eliminate the possibility of intestinal injury but should make great vessel injury extremely unlikely. Because of the difficulties in visual-izing the abdominal region immediately adjacent to the primary trocar, it is recommended that the telescope be passed through a secondary trocar to inspect the site of initial abdominal access.40 Secondary punctures are made with 5and 10-mm trocars. For safe access to the abdominal cavity, it is critical to visualize all sites of trocar entry.41,42 At the completion of the operation, all trocars are removed under direct vision, and the insertion sites are inspected for bleeding. If bleeding occurs, direct pres-sure with an instrument from another trocar site or balloon tamponade with a Foley catheter placed through the trocar site generally stops the bleeding within 3 to 5 minutes. When this is not successful, a full-thickness abdominal wall suture has been used successfully to tamponade trocar site


Surgery_Schwartz

Surgery_Schwartz. through the trocar site generally stops the bleeding within 3 to 5 minutes. When this is not successful, a full-thickness abdominal wall suture has been used successfully to tamponade trocar site bleeding.It is generally agreed that 5-mm trocars need no site sutur-ing. Ten-millimeter trocars placed off the midline, through a radially dilating sheath or above the transverse mesocolon do not typically require repair. Conversely, if the fascia has been dilated to allow the passage of the gallbladder or other organ, it should be repaired at the fascial level with interrupted sutures. The port site may be closed with suture delivery systems simi-lar to crochet needles enabling mass closure of the abdominal wall. This is especially helpful in obese patients where direct fascial closure may be challenging, through a small skin inci-sion. Failure to close lower abdominal trocar sites that are 10 mm in diameter or larger can lead to an incarcerated hernia.Access for Subcutaneous and


Surgery_Schwartz

Surgery_Schwartz. may be challenging, through a small skin inci-sion. Failure to close lower abdominal trocar sites that are 10 mm in diameter or larger can lead to an incarcerated hernia.Access for Subcutaneous and Extraperitoneal SurgeryThere are two methods for gaining access to nonanatomic spaces. For retroperitoneal locations, balloon dissection is effec-tive. This access technique is appropriate for the extraperitoneal repair of inguinal hernias and for retroperitoneal surgery for adrenalectomy, nephrectomy, lumbar discectomy, pancreatic necrosectomy, or para-aortic lymph node dissection.43,44 The Brunicardi_Ch14_p0453-p0478.indd 46001/03/19 4:58 PM 461MINIMALLY INVASIVE SURGERYCHAPTER 14initial access to the extraperitoneal space is performed in a way similar to direct puncture laparoscopy, except that the last layer (the peritoneum) is not traversed. Once the transversalis fascia has been punctured, a specialized trocar with a balloon on the end is introduced. The balloon is inflated in


Surgery_Schwartz

Surgery_Schwartz. that the last layer (the peritoneum) is not traversed. Once the transversalis fascia has been punctured, a specialized trocar with a balloon on the end is introduced. The balloon is inflated in the extraperitoneal space to create a working chamber. The balloon then is deflated, and a Hasson trocar is placed. An insufflation pressure of 10 mmHg usually is adequate to keep the extraperitoneal space open for dissection and will limit subcutaneous emphysema. Higher gas pressures force CO2 into the soft tissues and may contribute to hypercarbia. Extraperitoneal endosurgery provides less working space than laparoscopy but eliminates the possibil-ity of intestinal injury, intestinal adhesion, herniation at the tro-car sites, and ileus. These issues are important for laparoscopic hernia repair because extraperitoneal approaches prevent the small bowel from sticking to the prosthetic mesh.34Subcutaneous surgery has been most widely used in car-diac, vascular, and plastic surgery.36 In cardiac


Surgery_Schwartz

Surgery_Schwartz. extraperitoneal approaches prevent the small bowel from sticking to the prosthetic mesh.34Subcutaneous surgery has been most widely used in car-diac, vascular, and plastic surgery.36 In cardiac surgery, subcu-taneous access has been used for saphenous vein harvesting, and in vascular surgery for ligation of subfascial perforating veins (Linton procedure). With minimally invasive techniques, the entire saphenous vein above the knee may be harvested through a single incision (Fig. 14-8).45,46 Once the saphenous vein is located, a long retractor that holds a 5-mm laparoscope allows the coaxial dissection of the vein and coagulation or clipping of Figure 14-8. With two small incisions, virtually the entire saphe-nous vein can be harvested for bypass grafting.each side branch. A small incision above the knee also can be used to ligate perforating veins in the lower leg.Subcutaneous access also is used for plastic surgery pro-cedures.46 Minimally invasive approaches are especially well


Surgery_Schwartz

Surgery_Schwartz. above the knee also can be used to ligate perforating veins in the lower leg.Subcutaneous access also is used for plastic surgery pro-cedures.46 Minimally invasive approaches are especially well suited to cosmetic surgery, in which attempts are made to hide the incision. It is easier to hide several 5-mm incisions than one long incision. The technique of blunt dissection along fascial planes combined with lighted retractors and endoscope-holding retractors is most successful for extensive subcutaneous surgery. Some prefer gas insufflation of these soft tissue planes. The pri-mary disadvantage of soft tissue insufflation is that subcutane-ous emphysema can be created.Hand-Assisted Laparoscopic AccessHand-assisted laparoscopic surgery is thought to combine the tactile advantages of open surgery with the minimal access of laparoscopy and thoracoscopy. This approach commonly is used to assist with difficult cases before conversion to celiotomy is necessary. Additionally, hand-assisted


Surgery_Schwartz

Surgery_Schwartz. surgery with the minimal access of laparoscopy and thoracoscopy. This approach commonly is used to assist with difficult cases before conversion to celiotomy is necessary. Additionally, hand-assisted laparoscopic surgery is used to help surgeons negotiate the steep learning curve associ-ated with advanced laparoscopic procedures.47 This technology uses an entryway for the hand that preserves the pneumoperi-toneum and enables laparoscopic visualization in combination with the use of minimally invasive instruments (Fig. 14-9). For-mal investigation of this modality has been limited primarily to case reports and small series and has focused primarily on solid organ and colon surgery.Intraperitoneal, intrathoracic, and retroperitoneal access for robotic surgery adheres to the principles of laparoscopic and thoracoscopic access; however, the port size for the primary puncture is 12 mm to allow placement of the stereo laparoscope. Remaining trocars are 8 mm.Natural Orifice Transluminal


Surgery_Schwartz

Surgery_Schwartz. laparoscopic and thoracoscopic access; however, the port size for the primary puncture is 12 mm to allow placement of the stereo laparoscope. Remaining trocars are 8 mm.Natural Orifice Transluminal Endoscopic Surgery AccessMultiple studies have shown safety in the performance of NOTES procedures. Transvaginal, transvesicle, transanal, transcolonic, transgastric, and transoral approaches have all been attempted with varying success. The ease of decontamina-tion, entry, and closure of these structures create variable chal-lenges. The transvaginal approach for resection of the uterus has been employed for many years by gynecologists and has been modified by laparoscopists with great success. Extraction of the gallbladder, kidney, bladder, large bowel, and stomach can be Figure 14-9. This is an example of hand-assisted laparoscopic surgery during left colectomy. The surgeon uses a hand to provide retraction and counter tension during mobilization of the colon from its retroperitoneal


Surgery_Schwartz

Surgery_Schwartz. is an example of hand-assisted laparoscopic surgery during left colectomy. The surgeon uses a hand to provide retraction and counter tension during mobilization of the colon from its retroperitoneal attachments, as well as during division of the mesocolon. This technique is particularly useful in the region of the transverse colon.Brunicardi_Ch14_p0453-p0478.indd 46101/03/19 4:58 PM 462BASIC CONSIDERATIONSPART IFigure 14-10. Submucosal tunnel technique for transesophageal mediastinoscopy. (Reproduced with permission from Khashab MA, Kalloo AN. NOTES: current status and new horizons, Gastroenterology. 2012 Apr;142(4):704-710.e1.)performed via the vagina. The esophagus can be traversed to enter the mediastinum. Leaving the orifice or organ of entry with an endoscope requires the use of an endoscopic needle knife followed by submucosal tunneling or direct puncture and balloon dilation (Fig. 14-10). Closure has been performed using endoscopic clips or sutures with advanced endoscopic


Surgery_Schwartz

Surgery_Schwartz. an endoscopic needle knife followed by submucosal tunneling or direct puncture and balloon dilation (Fig. 14-10). Closure has been performed using endoscopic clips or sutures with advanced endoscopic platforms.Single-Incision Laparoscopic Surgery AccessThere is no standardized approach for SILS, and access tech-niques vary by surgeon preference. Traditionally, a single skin incision is made directly through the umbilical scar ranging from 1 to 3 cm. Through this single incision, multiple low-profile trocars can be placed separately into the fascia to allow insufflation, camera, and working instruments. The advantage of this technique is that conventional laparoscopic tools can be employed. The disadvantage becomes apparent when an extrac-tion site is needed. A variety of specialized multilumen trocars are on the market that can be placed through the umbilical ring48 (Fig. 14-11A,B). The advantages of these devices include faster access, improved safety, minimization of air leaks, and


Surgery_Schwartz

Surgery_Schwartz. trocars are on the market that can be placed through the umbilical ring48 (Fig. 14-11A,B). The advantages of these devices include faster access, improved safety, minimization of air leaks, and plat-form-derived instrument triangulation. The major disadvantage is cost.Port PlacementTrocars for the surgeon’s left and right hand should be placed at least 10 cm apart. For most operations, it is possible to orient ABCDEthe telescope between these two trocars and slightly back from them. The ideal trocar orientation creates an equilateral triangle between the surgeon’s right hand, left hand, and the telescope, with 10 to 15 cm on each leg. If one imagines the target of the operation (e.g., the gallbladder or gastroesophageal junc-tion) oriented at the apex of a second equilateral triangle built on the first, these four points of reference create a diamond (Fig. 14-12). The surgeon stands behind the telescope, which provides optimal ergonomic orientation but frequently requires that a


Surgery_Schwartz

Surgery_Schwartz. built on the first, these four points of reference create a diamond (Fig. 14-12). The surgeon stands behind the telescope, which provides optimal ergonomic orientation but frequently requires that a camera operator (or mechanical camera holder) reach between the surgeon’s hands to guide the telescope. SILS is challenging for even the experienced laparoscopist because it violates most of the aforementioned ergonomic principles. Hav-ing only a single point of entry into the abdominal cavity creates an inherently crowded port and hand position. The inability to space trocars severely limits the ability to triangulate the leftand right-hand instruments. As a result, the surgeon must often work in a crossed hands fashion (Fig. 14-13). Additionally, the axis of the camera view is often in line with the working instru-ments, making visualization difficult without a deflectable tip laparoscope.The position of the operating table should permit the sur-geon to work with both elbows in at the


Surgery_Schwartz

Surgery_Schwartz. with the working instru-ments, making visualization difficult without a deflectable tip laparoscope.The position of the operating table should permit the sur-geon to work with both elbows in at the sides, with arms bent 90° at the elbow.49 It usually is necessary to alter the operating table position with left or right tilt with the patient in the Tren-delenburg or reverse Trendelenburg position, depending on the operative field.50,51Brunicardi_Ch14_p0453-p0478.indd 46201/03/19 4:58 PM 463MINIMALLY INVASIVE SURGERYCHAPTER 14Figure 14-11. A. Specialized multilumen trocars can facilitate instrument placement. B. For single-incision laparoscopic surgery, multiple fascial punctures can be performed via a single skin incision. (Reproduced with permission from The Johns Hopkins University School of Medicine, Baltimore, MD; 2014. Illustration by Corinne Sandone.)Multiple trocarsthrough singleskin incision Single portaccommodatesmultiple trocarsABTHE DIAMOND OF SUCCESS"Home


Surgery_Schwartz

Surgery_Schwartz. University School of Medicine, Baltimore, MD; 2014. Illustration by Corinne Sandone.)Multiple trocarsthrough singleskin incision Single portaccommodatesmultiple trocarsABTHE DIAMOND OF SUCCESS"Home plate"(telescope)"First base"(R hand)"Third base"(L hand)"Second base"(hiatal hernia)15 cmFigure 14-12. The diamond configuration created by placing the telescope between the left and the right hand, recessed from the target by about 15 cm. The distance between the left and the right hand is also ideally 10 to 15 cm. In this “baseball diamond” con-figuration, the surgical target occupies the second base position.Figure 14-13. The single point of abdominal entry for trocars often requires that the surgeon work in a crossed hands fashion. (Reproduced with permission from The Johns Hopkins University School of Medi-cine, Baltimore, MD; 2014. Illustration by Corinne Sandone.)Imaging SystemsTwo methods of videoendoscopic imaging are widely used. Both methods use a camera with a charge-coupled


Surgery_Schwartz

Surgery_Schwartz. School of Medi-cine, Baltimore, MD; 2014. Illustration by Corinne Sandone.)Imaging SystemsTwo methods of videoendoscopic imaging are widely used. Both methods use a camera with a charge-coupled device (CCD), which is an array of photosensitive sensor elements (pixels) that convert the incoming light intensity to an electric charge. The electric charge is subsequently converted into a color image.52With videoendoscopy, the CCD chip is placed on the inter-nal end of a long, flexible endoscope. With older flexible endo-scopes, thin quartz fibers are packed together in a bundle, and the CCD camera is mounted on the external end of the endoscope. Most standard GI endoscopes have the CCD chip at the distal end, but small, delicate choledochoscopes and nephroscopes are equipped with fiber-optic bundles.53 Distally mounted CCD chips have been developed for laparoscopy but remain very expensive and therefore have not become as widely used.Video cameras come in two basic designs. Nearly all


Surgery_Schwartz

Surgery_Schwartz. bundles.53 Distally mounted CCD chips have been developed for laparoscopy but remain very expensive and therefore have not become as widely used.Video cameras come in two basic designs. Nearly all lapa-roscopic cameras contain a red, green, and blue input, and are identical to the color cameras used for television production.52 An additional feature of many video cameras is digital enhance-ment. Digital enhancement detects edges, areas where there are drastic color or light changes between two adjacent pixels.54 By enhancing this difference, the image appears sharper and surgi-cal resolution is improved. New laparoscopic cameras contain a high-definition (HD) chip, which increases the lines of resolu-tion from 480 to 1080 lines. To enjoy the benefit of the clarity of HD video imaging, HD monitors also are necessary.Priorities in a video imaging system for MIS are illumina-tion first, resolution second, and color third. Without the first two attributes, video surgery is unsafe.


Surgery_Schwartz

Surgery_Schwartz. HD monitors also are necessary.Priorities in a video imaging system for MIS are illumina-tion first, resolution second, and color third. Without the first two attributes, video surgery is unsafe. Illumination and resolu-tion are as dependent on the telescope, light source, and light cable as on the video camera used. Imaging for laparoscopy, thoracoscopy, and subcutaneous surgery uses a rigid metal telescope, usually 30 cm in length. Longer telescopes are avail-able for obese patients and for reaching the mediastinum and deep in the pelvis from a periumbilical entry site. The standard Brunicardi_Ch14_p0453-p0478.indd 46301/03/19 4:58 PM 464BASIC CONSIDERATIONSPART IFigure 14-14. The laparoscope tips come in a variety of angled configurations. All laparoscopes have a 70° field of view. A 30°-angled scope enables the surgeon to view this field at a 30° angle to the long axis of the scope.Figure 14-15. The Hopkins rod lens telescope includes a series of optical rods that effectively


Surgery_Schwartz

Surgery_Schwartz. A 30°-angled scope enables the surgeon to view this field at a 30° angle to the long axis of the scope.Figure 14-15. The Hopkins rod lens telescope includes a series of optical rods that effectively transmit light to the eyepiece. The video camera is placed on the eyepiece to provide the working image. The image is only as clear as the weakest link in the image chain. CCD = charge-coupled device. (Reproduced with permission from Toouli JG, Gossot D, Hunter JG: Endosurgery. New York/London: Churchill-Livingstone/Elsevier; 1996.)telescope contains a series of quartz optical rods and focusing lenses.55 Telescopes vary in size from 2 to 12 mm in diameter. Because light transmission is dependent on the cross-sectional area of the quartz rod, when the diameter of a rod/lens system is doubled, the illumination is quadrupled. Little illumination is needed in highly reflective, small spaces such as the knee, and a very small telescope will suffice. When working in the abdomi-nal cavity,


Surgery_Schwartz

Surgery_Schwartz. the illumination is quadrupled. Little illumination is needed in highly reflective, small spaces such as the knee, and a very small telescope will suffice. When working in the abdomi-nal cavity, especially if blood is present, the full illumination of a 10-mm telescope usually is necessary.Rigid telescopes may have a flat or angled end. The flat end provides a straight view (0°), and the angled end provides an oblique view (30° or 45°).52 Angled telescopes allow greater flexibility in viewing a wider operative field through a single trocar site (Fig. 14-14A); rotating an angled telescope changes LampLight sourceCameracontrollerCameraobjectivelensRelayedimageIlluminationlight guideImage formedby objective lensObservationpositionAdaption opticObjectivelens sectionRelaylens sectionEyepiecelens sectionFocus ringCCD chipMonitorCondensor lensLight guide cablethe field of view. The use of an angled telescope has distinct advantages for most videoendoscopic procedures, particularly in


Surgery_Schwartz

Surgery_Schwartz. sectionFocus ringCCD chipMonitorCondensor lensLight guide cablethe field of view. The use of an angled telescope has distinct advantages for most videoendoscopic procedures, particularly in visualizing the common bile duct during laparoscopic cho-lecystectomy or visualizing the posterior esophagus or the tip of the spleen during laparoscopic fundoplication. Flexible tip laparoscopes offer even greater optical freedom.Light is delivered to the endoscope through a fiber-optic light cable. These light cables are highly inefficient, losing >90% of the light delivered from the light source. Extremely bright light sources (300 watts) are necessary to provide ade-quate illumination for laparoscopic surgery.The quality of the videoendoscopic image is only as good as the weakest component in the imaging chain (Fig. 14-15). Therefore, it is important to use a video monitor that has a reso-lution equal to or greater than the camera being used.55 Resolu-tion is the ability of the optical system


Surgery_Schwartz

Surgery_Schwartz. imaging chain (Fig. 14-15). Therefore, it is important to use a video monitor that has a reso-lution equal to or greater than the camera being used.55 Resolu-tion is the ability of the optical system to distinguish between line pairs. The larger the number of line pairs per millimeter, the sharper and more detailed the image. Most high-resolution monitors have up to 700 horizontal lines. HD television can deliver up to eight times more resolution than standard moni-tors; when combined with digital enhancement, a very sharp and well-defined image can be achieved.52,55 A heads-up display is a high-resolution liquid crystal monitor that is built into eyewear worn by the surgeon.56 This technology allows the surgeon to view the endoscopic image and operative field simultaneously. The proposed advantages of heads-up display include a high-resolution monocular image, which affords the surgeon mobility and reduces vertigo and eyestrain. However, this technology has not yet been widely


Surgery_Schwartz

Surgery_Schwartz. advantages of heads-up display include a high-resolution monocular image, which affords the surgeon mobility and reduces vertigo and eyestrain. However, this technology has not yet been widely adopted.Interest in three-dimensional (3-D) laparoscopy has waxed and waned. 3-D laparoscopy provides the additional depth of field that is lost with two-dimensional endosurgery and improves performance of novice laparoscopists performing complex tasks of dexterity, including suturing and knot tying.57 The advantages of 3-D systems are less obvious to experienced Brunicardi_Ch14_p0453-p0478.indd 46401/03/19 4:58 PM 465MINIMALLY INVASIVE SURGERYCHAPTER 14laparoscopists. Additionally, because 3-D systems require the flickering of two similar images, which are resolved with spe-cial glasses, the images’ edges become fuzzy and resolution is lost. The optical accommodation necessary to rectify these slightly differing images is tiring and may induce headaches when one uses these systems for a


Surgery_Schwartz

Surgery_Schwartz. images’ edges become fuzzy and resolution is lost. The optical accommodation necessary to rectify these slightly differing images is tiring and may induce headaches when one uses these systems for a long period of time. The da Vinci robot uses a specialized laparoscope with two optical bundles on opposite sides of the telescope. A specialized bin-ocular eyepiece receives input from two CCD chips, each cap-turing the image from one of the two quartz rod lens systems, thereby creating true 3-D imaging without needing to employ active or passive technologies that have made 3-D laparoscopy so disappointing.Single-incision laparoscopy presents new challenges to visualization of the operative field. In the traditional laparo-scope, the light source enters the scope at a 90° angle. That position coupled with a bulky scope handle creates crowding in an already limited space. Additionally, because the scope and instruments enter the abdomen at the same point, an adequate perspective is often


Surgery_Schwartz

Surgery_Schwartz. coupled with a bulky scope handle creates crowding in an already limited space. Additionally, because the scope and instruments enter the abdomen at the same point, an adequate perspective is often unobtainable even with a 30° scope. The advent of increased length laparoscopes with lighting coming from the end and a deflectable tip now allows the surgeon to recreate a sense of internal triangulation with little compromise externally. The ability to move the shaft of the scope off line while maintaining the same image provides a greater degree of freedom for the working ports.Energy Sources for Endoscopic and Endoluminal SurgeryMany MIS procedures use conventional energy sources, but the benefits of bloodless surgery to maintain optimal visualization have spawned new ways of applying energy. The most common energy source is RF electrosurgery using an alternating current with a frequency of 500,000 cycles/s (Hz). Tissue heating pro-gresses through the well-known phases of coagulation


Surgery_Schwartz

Surgery_Schwartz. The most common energy source is RF electrosurgery using an alternating current with a frequency of 500,000 cycles/s (Hz). Tissue heating pro-gresses through the well-known phases of coagulation (60°C [140°F]), vaporization and desiccation (100°C [212°F]), and carbonization (>200°C [392°F]).58The two most common methods of delivering RF electro-surgery are with monopolar and bipolar electrodes. With mono-polar electrosurgery, a remote ground plate on the patient’s leg or back receives the flow of electrons that originate at a point source, the surgical electrode. A fine-tipped electrode causes a high current density at the site of application and rapid tissue heating. Monopolar electrosurgery is inexpensive and easy to modulate to achieve different tissue effects.59 A short-duration, high-voltage discharge of current (coagulation current) provides extremely rapid tissue heating. Lower-voltage, higher-wattage current (cutting current) is better for tissue desiccation and vaporization.


Surgery_Schwartz

Surgery_Schwartz. discharge of current (coagulation current) provides extremely rapid tissue heating. Lower-voltage, higher-wattage current (cutting current) is better for tissue desiccation and vaporization. When the surgeon desires tissue division with the least amount of thermal injury and least coagulation necrosis, a cutting current is used.With bipolar electrosurgery, the electrons flow between two adjacent electrodes. The tissue between the two electrodes is heated and desiccated. There is little opportunity for tissue cutting when bipolar current is used alone, but the ability to coapt the electrodes across a vessel provides the best method of small-vessel coagulation without thermal injury to adjacent tissues.60 Advanced laparoscopic device manufacturers have leveraged the ability to selectively use bipolar energy and combined it with compressive force and a controllable blade to create a number of highly functional dissection and vessel-sealing tools (Fig. 14-16).Figure 14-16. Examples of


Surgery_Schwartz

Surgery_Schwartz. use bipolar energy and combined it with compressive force and a controllable blade to create a number of highly functional dissection and vessel-sealing tools (Fig. 14-16).Figure 14-16. Examples of advanced bipolar devices. The flow of electrons passes from one electrode to the other heating and desic-cating tissue. A controllable blade travels the length of the jaw to divide intervening tissue.To avoid thermal injury to adjacent structures, the lapa-roscopic field of view must include all uninsulated portions of the electrosurgical electrode. In addition, the integrity of the insulation must be maintained and assured. Capacitive coupling occurs when a plastic trocar insulates the abdominal wall from the current; in turn, the current is bled off of a metal sleeve or laparoscope into the viscera54 (Fig. 14-17A). This may result in thermal necrosis and a delayed fecal fistula. Another potential mechanism for unrecognized visceral injury may occur with the direct coupling of current to


Surgery_Schwartz

Surgery_Schwartz. viscera54 (Fig. 14-17A). This may result in thermal necrosis and a delayed fecal fistula. Another potential mechanism for unrecognized visceral injury may occur with the direct coupling of current to the laparoscope and adjacent bowel58 (Fig. 14-17B).Another method of delivering RF electrosurgery is argon beam coagulation. This is a type of monopolar electrosurgery in which a uniform field of electrons is distributed across a tissue surface by the use of a jet of argon gas. The argon gas jet distrib-utes electrons more evenly across the surface than does spray electrofulguration. This technology has its greatest application for coagulation of diffusely bleeding surfaces such as the cut edge of liver or spleen. It is of less value in laparoscopic proce-dures because the increased intra-abdominal pressures created by the argon gas jet can increase the chances of a gas embolus. It is paramount to vent the ports and closely monitor insufflation pressure when using this source of energy


Surgery_Schwartz

Surgery_Schwartz. pressures created by the argon gas jet can increase the chances of a gas embolus. It is paramount to vent the ports and closely monitor insufflation pressure when using this source of energy within the context of laparoscopy.With endoscopic endoluminal surgery, RF alternating cur-rent in the form of a monopolar circuit represents the mainstay for procedures such as snare polypectomy, sphincterotomy, lower esophageal sphincter ablation, and biopsy.61,62 A ground-ing (return) electrode is necessary for this form of energy. Bipo-lar electrocoagulation is used primarily for thermal hemostasis. The electrosurgical generator is activated by a foot pedal so the endoscopist may keep both hands free during the endoscopic procedure.Gas, liquid, and solid-state lasers have been available for medical application since the mid-1960s.63 The CO2 laser (wavelength 10.6 µm) is most appropriately used for cutting Brunicardi_Ch14_p0453-p0478.indd 46501/03/19 4:58 PM 466BASIC


Surgery_Schwartz

Surgery_Schwartz. available for medical application since the mid-1960s.63 The CO2 laser (wavelength 10.6 µm) is most appropriately used for cutting Brunicardi_Ch14_p0453-p0478.indd 46501/03/19 4:58 PM 466BASIC CONSIDERATIONSPART IFigure 14-17. A. Capacitive coupling occurs as a result of high current density bleeding from a port sleeve or laparoscope into adjacent bowel. B. Direct coupling occurs when current is transmitted directly from the electrode to a metal instrument or laparoscope, and then into adjacent tissue. (Reproduced with permission from Hunter JG, Sackier JM: Minimally Invasive Surgery. New York, NY: McGraw-Hill Education; 1993.)Figure 14-18. This graph shows the absorption of light by various tissue compounds (water, melanin, and oxyhemoglobin) as a func-tion of the wavelength of the light. The nadir of the oxyhemoglo-bin and melanin curves is close to 1064 nm, the wavelength of the neodymium yttrium-aluminum garnet laser. (Reproduced with per-mission from Hunter JG, Sackier JM:


Surgery_Schwartz

Surgery_Schwartz. light. The nadir of the oxyhemoglo-bin and melanin curves is close to 1064 nm, the wavelength of the neodymium yttrium-aluminum garnet laser. (Reproduced with per-mission from Hunter JG, Sackier JM: Minimally Invasive Surgery. New York, NY: McGraw-Hill Education; 1993.)Conduction through ungrounded telescopeCannulaPlastic cannulaTelescopeBCapacitive coupled fault conditionCapacitivelycoupled energyto metalcannulaPlastic collarover metaltrocarAand superficial ablation of tissues. It is most helpful in locations unreachable with a scalpel such as excision of vocal cord granu-lomas. The CO2 laser beam must be delivered with a series of mirrors and is therefore somewhat cumbersome to use. The next most popular laser is the neodymium yttrium-aluminum garnet (Nd:YAG) laser. Nd:YAG laser light is 1.064 µm (1064 nm) in wavelength. It is in the near-infrared portion of the spectrum and, like CO2 laser light, is invisible to the naked eye. A unique feature of the Nd:YAG laser is that 1064-nm


Surgery_Schwartz

Surgery_Schwartz. is 1.064 µm (1064 nm) in wavelength. It is in the near-infrared portion of the spectrum and, like CO2 laser light, is invisible to the naked eye. A unique feature of the Nd:YAG laser is that 1064-nm light is poorly absorbed by most tissue pigments and therefore travels deep into tissue.64 Deep tissue penetration provides deep tissue heating (Fig. 14-18). For this reason, the Nd:YAG laser is capable of the greatest amount of tissue destruction with a single application.63 Absorption coefficientWavelength (nm)10610510410310210110–110–211001000 10,000UV Visible InfaredHbO2H2OH2O1064 nmMelanin Such capabilities make it the ideal laser for destruction of large fungating tumors of the rectosigmoid, tracheobronchial tree, or esophagus. A disadvantage is that the deep tissue heating may cause perforation of a hollow viscus.When it is desirable to coagulate flat lesions in the cecum, a different laser should be chosen. The frequency-doubled Nd:YAG laser, also known as the


Surgery_Schwartz

Surgery_Schwartz. heating may cause perforation of a hollow viscus.When it is desirable to coagulate flat lesions in the cecum, a different laser should be chosen. The frequency-doubled Nd:YAG laser, also known as the KTP laser (potassium thionyl phosphate crystal is used to double the Nd:YAG frequency), pro-vides 532-nm light. This is in the green portion of the spectrum, and at this wavelength, selective absorption by red pigments in tissue (such as hemangiomas and arteriovenous malformations) is optimal. The depth of tissue heating is intermediate, between those of the CO2 and the Nd:YAG lasers. Coagulation (without vaporization) of superficial vascular lesions can be obtained without intestinal perforation.64In flexible GI endoscopy, the CO2 and Nd:YAG lasers have largely been replaced by heater probes and endoluminal stents. The heater probe is a metal ball that is heated to a tem-perature (60–100°C [140°–212°F]) that allows coagulation of bleeding lesions without perforation.Photodynamic therapy


Surgery_Schwartz

Surgery_Schwartz. and endoluminal stents. The heater probe is a metal ball that is heated to a tem-perature (60–100°C [140°–212°F]) that allows coagulation of bleeding lesions without perforation.Photodynamic therapy is a palliative treatment for obstruct-ing cancers of the GI tract.65 Patients are given an IV dose of porfimer sodium, which is a photosensitizing agent that is taken up by malignant cells. Two days after administration, the drug is endoscopically activated using a laser. The activated porfimer sodium generates oxygen free radicals, which kill the tumor cells. The tumor is later endoscopically debrided. The use of this modality for definitive treatment of early cancers is limited.A unique application of laser technology provides extremely rapid discharge (<10–6 s) of large amounts of energy (>103 volts). These high-energy lasers, of which the pulsed dye laser has seen the most clinical use, allow the conversion of light energy to mechanical disruptive energy in the form of a shock wave.


Surgery_Schwartz

Surgery_Schwartz. (>103 volts). These high-energy lasers, of which the pulsed dye laser has seen the most clinical use, allow the conversion of light energy to mechanical disruptive energy in the form of a shock wave. Such energy can be delivered through a quartz fiber, and with rapid repetitive discharges, can provide sufficient shock-wave energy to fragment kidney stones and gallstones.66 Shock waves also may be created with miniature electric spark-plug discharge systems known as electrohydraulic lithotriptors. These devices Brunicardi_Ch14_p0453-p0478.indd 46601/03/19 4:58 PM 467MINIMALLY INVASIVE SURGERYCHAPTER 14also are inserted through thin probes for endoscopic application. Lasers have the advantage of pigment selectivity, but electrohy-draulic lithotriptors are more popular because they are substan-tially less expensive and are more compact.Methods of producing shock waves or heat with ultrasonic energy are also of interest. Extracorporeal shockwave lithotripsy creates focused shock waves


Surgery_Schwartz

Surgery_Schwartz. less expensive and are more compact.Methods of producing shock waves or heat with ultrasonic energy are also of interest. Extracorporeal shockwave lithotripsy creates focused shock waves that intensify as the focal point of the discharge is approached. When the focal point is within the body, large amounts of energy are capable of fragmenting stones. Slightly different configurations of this energy can be used to provide focused internal heating of tissues. Potential applications of this technology include the ability to noninvasively produce sufficient internal heating to destroy tissue without an incision.A third means of using ultrasonic energy is to create rap-idly oscillating instruments that are capable of heating tissue with friction; this technology represents a major step forward in energy technology.67 An example of its application is the lapa-roscopic coagulation shears device (Harmonic Scalpel), which is capable of coagulating and dividing blood vessels by first occluding