Obstentrics_Williams

Obstentrics_Williams. As with many other aspects of breech position, induction or augmentation of labor is controversial. Here again, data are limited and mostly retrospective. With labor induction, Burgos and coworkers (2017) reported equivalent vaginal delivery rates compared with spontaneous labor. With induction, however, they reported higher rates of neonatal intensive care unit admission. But, others have found similar perinatal outcome and cesarean delivery rates Qarniat, 2017; Marzouk, 2011). Finally, others described greater cesarean delivery rates with induction but similar neonatal outcomes (Macharey, 2016).


Obstentrics_Williams

Obstentrics_Williams. In many studies, successful vaginal delivery is associated with orderly labor progression. hus, some protocols avoid augmentation for the breech-presenting fetus, whereas others recommend it only for hypotonic contractions (Alarab, 2004; Kotaska, 2009). In women with a viable fetus, at Parkland Hospital, we attempt amniotomy induction but prefer cesarean delivery instead of pharmacological labor induction or augmentation.


Obstentrics_Williams

Obstentrics_Williams. On arrival to the labor unit, surveillance offetal heart rate and uterine contractions begins, and immediate recruitment of necessary staf includes: (1) a provider skilled in the art of breech extraction, an associate to assist with the delivery, (3) anesthesia personnel who can ensure adequate analgesia or anesthesia when needed, and an individual trained in newborn resuscitation. For the mother, intravenous access is obtained. his allows, if needed, emergency induction of anesthesia or maternal resuscitation following hemorrhage from lacerations or from uterine atony.


Obstentrics_Williams

Obstentrics_Williams. At admission, the status of the membranes and progression of labor are assessed. Knowledge regarding cervical dilatation, cervical efacement, and presenting part station is essential for preparation. If labor is too far advanced, pelvimetry may be unsafe if fetal expulsion in the radiology department is a pos sibility. This alone, however, should not force the decision for cesarean delivery. As mentioned, stepwise labor progression itself is a good indicator of pelvic adequacy (Biswas, 1993). Sonographic assessment, described earlier, is completed. Ulti mately, the choice of abdominal or vaginal delivery is based on factors discussed earlier and listed in Table 28-1.


Obstentrics_Williams

Obstentrics_Williams. Sonographic assessment, described earlier, is completed. Ulti mately, the choice of abdominal or vaginal delivery is based on factors discussed earlier and listed in Table 28-1. During labor, one-on-one nursing is ideal because of cord prolapse risks, and physicians must be readily available for such emergencies. Guidelines for monitoring the high-risk fetus are applied (Chap. 24, p. 478). For first-stage labor, while most clini cians prefer continuous electronic monitoring, the fetal heart rate is recorded at a minimum of every 15 minutes. A scalp electrode can be safely aixed to the buttock, but genitalia are avoided. If a nonreassuring fetal heart rate pattern develops, then a decision must be made regarding the necessity of cesarean delivery.


Obstentrics_Williams

Obstentrics_Williams. When membranes rupture, either spontaneously or artificially, the cord prolapse risk is appreciable and is increased when the fetus is small or when the breech is not frank. Therefore, vaginal examination is performed immediately following rupture, and special attention is directed to the fetal heart rate for the irst 5 to 10 minutes thereafter. For women in labor with a breech presentation, continuous epidural analgesia is advocated by some. This may increase the need for labor augmentation and prolong second-stage labor (Chadha, 1992; Confino, 1985). hese potential disadvantages are weighed against the advantages of better pain relief and increased pelvic relaxation should extensive manipulation be required. Analgesia must be suicient for episiotomy, for breech extraction, and for Piper forceps application. Nitrous oxide plus oxygen inhalation can provide further relief from pain. If general anesthesia is required, it must be induced quickly.


Obstentrics_Williams

Obstentrics_Williams. Similar to vertex delivery, spontaneous expulsion of a breech fetus entails sequential cardinal movements. First, engagement and descent of the breech usually take place with the bitrochanteric diameter in one of the oblique pelvic diameters. The anterior hip usually descends more rapidly than the posterior hip, and when the resistance of the pelvic Boor is met, internal rotation of 45 degrees usually follows, bringing the anterior hip toward the pubic arch and allowing the bitrochanteric diameter to occupy the anteroposterior diameter of the pelvic outlet. If the posterior extremity is prolapsed, however, it, rather than the anterior hip, rotates to the symphysis pubis.


Obstentrics_Williams

Obstentrics_Williams. After rotation, descent continues until the perineum is distended by the advancing breech, and the anterior hip appears at the vulva. By lateral lexion of the fetal body, the posterior hip then is forced over the perineum, which retracts over the fetal buttocks, thus allowing the fetus to straighten out when the anterior hip is born (Fig. 28-4). he legs and feet follow the breech and may be born spontaneously or require aid. FIGURE 28-4 The hips of the frank breech are delivering over the perineum. The anterior hip usually delivers first.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-4 The hips of the frank breech are delivering over the perineum. The anterior hip usually delivers first. After the birth of the breech, there is slight external rotation, with the back turning anteriorly as the shoulders are brought into relation with one of the oblique diameters of the pelvis. The shoulders then descend rapidly and undergo internal rotation, with the bisacromial diameter occupying the anteroposterior plane. Immediately following the shoulders, the head, which is normally sharply flexed on the thorax, enters the pelvis in one of the oblique diameters and then rotates to bring the posterior portion of the neck under the symphysis pubis. The head is then born in flexion.


Obstentrics_Williams

Obstentrics_Williams. The breech may engage in the transverse diameter of the pelvis, with the sacrum directed anteriorly or posteriorly. he mechanism oflabor in the transverse position difers only in that internal rotation is through an arc of 90 rather than 45 degrees. Infrequently, rotation renders the back of the fetus to lie posteriorly instead of anteriorly. Such rotation is prevented if possible. Although the head can be delivered by allowing the chin and face to pass beneath the symphysis, the slightest traction on the body may cause extension of the head, which increases the diameter of the head that must pass through the pelvis. With breech delivery, successively larger and less compressible parts are born. Thus, spontaneous expulsion is the exception, and vaginal delivery typically requires skilled provider participation for the fetus to navigate the birth canal. Noteworthy clinical pearls are provided by Yeomans (2017) in the third edition of Cunningham and Gilstrap s Operative Obstetrics.


Obstentrics_Williams

Obstentrics_Williams. First, with all breech deliveries, unless the perineum is considerably lax, an episiotomy is made and is an important adjunct to delivery. As discussed in Chapter 27 (p. 529), mediolateral episiotomy may be preferred for its lower associated risk of anal FIGURE 28-5 To deliver the left leg, two fingers of the provider's left hand are placed beneath and parallel to the femur. The thigh is then slightly abducted and pressure from the fingertips in the popliteal fossa should induce knee flexion and bring the foot within reach. The foot is then grasped to gently deliver the entire leg outside the vagina. A similar procedure is followed on the right. (Figures 28-5 though 28-8: Reproduced with permission from Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New (ork, McGraw-Hili Education, 201o7.)


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-6 To deliver the body, thumbs are placed over the sacrum, and each index finger wraps over the top of the corresponding fetal iliac crest. Gentle downward traction is applied until the scapulas are clearly visible. (Reproduced with permission from Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hofman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 2017.)


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-7 A. After delivery of the first arm, 180-degree rotation of the fetal body brings the sacrum to a right sacrum transverse (RST) position. B. Fingers of the provider's hand extended over the right shoulder and parallel to the humerus. These sweep the arm downward across the chest and out. (Reproduced with permission from Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201o7.) sphincter lacerations. Ideally, the breech is allowed to deliver spontaneously to the umbilicus. Delivery of the breech draws the umbilicus and attached cord into the pelvis. Therefore, once the breech has passed beyond the vaginal introitus, the abdomen, thorax, arms, and head must be delivered promptly either spontaneously or assisted.


Obstentrics_Williams

Obstentrics_Williams. The posterior hip will deliver, usually from the 6 o'clock position, and oten with suicient pressure to evoke passage of thick meconium (see Fig. 28-4). he anterior hip then delivers, followed by external rotation to a sacrum anterior position. The mother is encouraged to continue to push as the fetus descends until the legs are accessible. The legs are sequentially delivered by splinting the femur with the operator's fingers positioned parallel to the long axis of the femur, and by exerting pressure upward and laterally to sweep each leg away from the midline (Fig. 28-5). Following delivery of the legs, the fetal bony pelvis is grasped with both hands. The fingers should rest on the anterior superior iliac crests and the thumbs on the sacrum. his minimizes the chance of fetal abdominal soft-tissue injury (Fig. 28-6). Maternal expulsive eforts are again used in conjunction with downward traction to afect delivery.


Obstentrics_Williams

Obstentrics_Williams. A cardinal rule in successul breech extraction is to employ steady, gentle, downward traction until the lower halves of the scapulas are delivered, making no attempt at delivery of the shoulders and arms until one axilla becomes visible. It makes little difference which shoulder is delivered irst, and two methods are suitable for their delivery. In the first method, with the scapulas visible, the trunk is rotated either clockwise or counterclocwise to bring the anterior shoulder and arm into view (Fig. 28-7). During delivery of the arm, fingers and hand are aligned parallel to the humerus and act to splint and prevent humeral fracture. he body of the fetus is then rotated 180 degrees in the reverse direction to bring the other shoulder and arm into position for delivery.


Obstentrics_Williams

Obstentrics_Williams. he second method is employed if trunk rotation is unsuccessful. With this maneuver, the posterior shoulder is delivered first. For this, the feet are grasped in one hand and drawn upward over the inner thigh of the mother (Fig. 28-8). The


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-8 Infrequently, the posterior arm must be delivered first. For this, the lower half of the fetal body is raised up and over the maternal groin. The provider's fingers are inserted under the posterior shoulder and aligned with the humerus. (Reproduced with permission from Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 2017.) hand enters over the shoulder, fingers are aligned parallel to the long axis of the humerus, and the fetal arm is swept upward. The posterior shoulder slides out over the perineal margin and is usually followed by the arm and hand. Then, by depressing the body of the fetus, the anterior shoulder emerges beneath the pubic arch, and the arm and hand usually follow spontaneously. After both shoulders are delivered, the back of the fetus tends to rotate spontaneously to the symphysis. Delivery of the head may then be


Obstentrics_Williams

Obstentrics_Williams. arch, and the arm and hand usually follow spontaneously. After both shoulders are delivered, the back of the fetus tends to rotate spontaneously to the symphysis. Delivery of the head may then be accomplished.


Obstentrics_Williams

Obstentrics_Williams. During delivery, one or both fetal arms occasionally may lie across the back of the neck and become impacted at the pelvic inlet. With such a nuchal arm, delivery is more diicult and can be aided by rotating the fetus through a half circle in such a direction that the friction exerted by the birth canal will draw the elbow toward the face (Fig. 28-9). With a right nuchal arm, the body should be rotated counterclockwise, which rotates the fetal back toward the maternal right. With a left nuchal arm, the rotation is clockwise. If rotation fails to free the nuchal arm, it may be necessary to push the fetus upward to a roomier part of the pelvis. If the rotation is still unsuccessul, the nuchal arm oten is extracted by hooking a inger(s) over it and forcing the arm over the shoulder, and down the ventral surface for delivery of the arm. In this event, fracture of the humerus or clavicle is common. Delivery of the Aftercoming Head


Obstentrics_Williams

Obstentrics_Williams. Delivery of the Aftercoming Head Mauriceau Maneuver. The fetal head is normally extracted with forceps or by one of several maneuvers. With any of these techniques, hyperextension of the fetal neck is avoided. With the Mauriceau maneuver, the index and middle inger of one hand are applied over the maxilla, to flex the head, while FIGURE 28-10 A. Delivery of the aftercoming head using the Mauriceau maneuver. Note that as the fetal head is being delivered, flexion of the head is maintained by suprapubic pressure provided by an assistant. B. Pressure on the maxilla is applied Simultaneously by the operator as upward and outward traction is exerted.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-9 Reduction of a right nuchal arm is accomplished by rotating the fetal body 180 degrees counterclockwise, which directs the fetal back to the maternal right. Friction exerted by the birth canal will draw the elbow toward the face. (Reproduced with permission from Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201•7.) the fetal body rests on the palm of the same hand and forearm (Fig. 28-10). Fetal legs straddle the forearm. Two ingers of the other hand then are hooked over the fetal neck and grasp the shoulders. Downward traction is concurrently applied until the suboccipital region appears under the symphysis. Gentle suprapubic pressure simultaneously applied by an assistant helps keep the head flexed. The body then is slightly elevated toward the maternal abdomen, and the mouth, nose, brow, and eventually the occiput emerge successively


Obstentrics_Williams

Obstentrics_Williams. applied by an assistant helps keep the head flexed. The body then is slightly elevated toward the maternal abdomen, and the mouth, nose, brow, and eventually the occiput emerge successively over the perineum. With this maneuver, the provider uses both hands simultaneously to exert continuous downward gentle traction while balancing forces between the fetal neck and maxilla to avoid neck hyperextension.


Obstentrics_Williams

Obstentrics_Williams. Forceps. Specialized forceps can be used to deliver the aftercoming head. Piper forceps, shown in Figure 28-11, or Laufe-Piper forceps may be applied electively or when the Mauriceau maneuver cannot be accomplished easily. The blades FIGURE 28-11 Piper forceps for delivery of the aftercoming head. A. The fetal body is held elevated using a warm towel and the left blade of forceps is applied to the aftercoming head. B.The right blade is applied with the body still elevated. C. Forceps delivery of the aftercom ing head. Note the direction of movement shown by the arrow. of the forceps are not applied to the aftercoming head until it has been brought into the pelvis by gentle traction, combined with suprapubic pressure, and is engaged. Suspension of the body of the fetus in a towel efectively holds the fetus up and helps keep the arms and cord out of the way as the forceps blades are applied.


Obstentrics_Williams

Obstentrics_Williams. Because the forceps blades are directed upward from the level of the perineum, some choose to apply them from a one-knee kneeling position. Piper forceps have a downward arch in the shank to accommodate the fetal body and lack a pelvic curve. This shape permits direct application of the cephalic curve of the blade along the length of the maternal vagina and fetal parietal bone. The blade to be placed on the maternal left is held in the provider's left hand. The right hand slides between the fetal head and left maternal vaginal sidewall to guide the blade inward and around the parietal bone. he opposite blade mirrors this application.


Obstentrics_Williams

Obstentrics_Williams. Once in place, the blades are articulated, and the fetal body rests across the shanks. The head is delivered by pulling gently outward and slightly raising the handle simultaneously. This rolls the face over the perineum, while the occiput remains beneath the symphysis until after the brow delivers. Ideally, the head and body move in unison to minimize neck hyperextension. Modified Prague Maneuver. Rarely, the back of the fetus fails to rotate to the symphysis. The fetus still may be delivered using the modiied Prague maneuver. With this, two fingers of one hand grasp the shoulders of the back-down fetus from below while the other hand draws the feet up and over the maternal abdomen (Fig. 28-12). FIGURE 28-12 Delivery of the aftercoming head using the modified Prague maneuver necessitated by failure of the fetal trunk to rotate anteriorly.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-12 Delivery of the aftercoming head using the modified Prague maneuver necessitated by failure of the fetal trunk to rotate anteriorly. FIGURE 28-13 Duhrssen incision being cut at 2 o'clock, which is followed by a second incision at 10 o'clock. Infrequently, an additional incision is required at 6 o'clock. The incisions are so placed as to minimize bleeding from the laterally located cervical branches of the uterine artery. After delivery, the incisions are repaired as described in Chapter 41 (p.o763).


Obstentrics_Williams

Obstentrics_Williams. Head Entrapment. his emergency reflects either an incompletely dilated cervix or cephalopelvic disproportion. First, especially with a small preterm fetus, an incompletely dilated cervix can constrict around the neck and impede delivery of the aftercoming head. At this point, signiicant cord compression must be assumed, and time management is essential. With gentle traction on the fetal body, the cervix, at times, may be manually slipped over the occiput. If unsuccessful, then Diihrssen incisions may be necessary (Fig. 28-13). General anesthesia with halogenated agents or intravenous nitroglycerin is another option to aid lower uterine segment relaxation. As an extreme measure, replacement of the fetus higher into the vagina and uterus, followed by cesarean delivery, can rescue an entrapped breech fetus. This Zavaneli maneuver is classically performed to relieve intractable shoulder dystocia (Sandberg, 1988). However, case reports also have described its use for an entrapped


Obstentrics_Williams

Obstentrics_Williams. entrapped breech fetus. This Zavaneli maneuver is classically performed to relieve intractable shoulder dystocia (Sandberg, 1988). However, case reports also have described its use for an entrapped aftercoming head (Sandberg, 1999; Steyn, 1994).


Obstentrics_Williams

Obstentrics_Williams. In cases with cephalopelvic disproportion and arrest of aftercoming head, the Zavanelli maneuver or symphysiotomy are options (Sunday-Adeoye, 2004; Wery, 2013). Using local analgesia, symphysiotomy surgically divides the intervening symphyseal cartilage and much of its ligamentous support to widen the symphysis pubis up to 2.5 cm (Basak, 2011). Lack of provider training and potentially serious maternal pelvic or urinary tract injury explain its rare use in the United States. That said, if cesarean delivery is not possible, symphysiotomy may be lifesaving for both mother and baby (Hofmeyr, 2012).


Obstentrics_Williams

Obstentrics_Williams. At times, total extraction of a complete or incomplete breech may be required. A hand is introduced through the vagina, and both fetal feet are grasped. he ankles are held with the middle finger lying between them. With gentle traction, the feet are brought through the introitus (Fig. 28-14). As the legs begin to emerge through the vulva, downward gentle traction is continued. As the legs emerge, successively higher portions are grasped, first the calves and then the thighs. When the breech appears at the vaginal outlet, gentle traction is applied until the hips are delivered. The thumbs are then placed over the sacrum and the fingers over the iliac crests. Breech extraction is then completed, as described for partial breech extraction (p. 544). FIGURE 28-14 Complete breech extraction begins with traction on the feet and ankles.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 28-14 Complete breech extraction begins with traction on the feet and ankles. If only one foot can be grasped, it can be brought down into the vagina and held with the appropriate hand, right hand for right foot and left hand for left foot (Yeomans, 2017). With the irst foot secure, the opposite hand is introduced, passed upward along the leg, and guided to locate the other foot. If the remaining hip is extended, the second foot is usually easily grasped and brought down. If the hip is lexed and knee extended, a finger is hooked into that groin, and traction will bring the lower half of the fetus down until the leg can be reached. For cesarean delivery, these total breech extraction maneuvers can be used to deliver a complete, incomplete, or footling breech through the hysterotomy incision.


Obstentrics_Williams

Obstentrics_Williams. During complete extraction of a frank breech, moderate traction is exerted by a finger in each groin and aided by a generous episiotomy. Once the breech is pulled through the introitus, the steps described for partial breech extraction are then completed (p. 544). These maneuvers are also used during cesarean delivery of a frank breech through a hysterotomy incision.


Obstentrics_Williams

Obstentrics_Williams. Rarely during vaginal delivery, a frank breech will require decomposition inside the uterine cavity. Attributed to Pinard (1889), this procedure converts a frank breech into a footling breech. It is accomplished more readily if the membranes have ruptured only recently. It becomes extremely diicult if amnionic luid is scant and the uterus is tightly contracted around the fetus. Pharmacological relaxation by general anesthesia or intravenous magnesium sulfate, nitroglycerin, or a betamimetic agent may be required. To begin, two ingers are carried up along one leg to externally rotate the hip by pressing on the medial side of the thigh parallel to the femur. Simultaneously, pressure in the popliteal fossa should prompt spontaneous knee flexion, which brings the corresponding foot into contact with the back of the provider's hand. he fetal foot then may be grasped and brought down.


Obstentrics_Williams

Obstentrics_Williams. With version, fetal presentation is altered by physically substituting one pole of a longitudinal presentation for the other, or converting an oblique or transverse lie into a longitudinal presentation. Manipulations performed through the abdominal wall that yield a cephalic presentation are termed external cephalic version. Manipulations accomplished inside the uterine cavity that yield a breech presentation are designated intenal podalic version. This latter procedure is reserved for delivery of a second twin and described in Chapter 45 (p. 890). External cephalic version (ECy) reduces the rate of noncephalic presentation at birth (Hofmeyr, 2015b). For breech fetuses near term, the American College of Obstetricians and Gynecologists (2016a,b) recommends that version be ofered and attempted whenever possible. Its success rate averages about 60 percent (de Hundt, 2014). For women with a transverse lie, the overall success rate is significantly higher.


Obstentrics_Williams

Obstentrics_Williams. In general, ECV is attempted before labor in a woman who has reached 37 weeks' gestation. Before this time, breech pre sentation still has a high likelihood of correcting spontaneously. And, if ECV is performed too early, time may allow a rever sion back to breech (Bogner, 2012). Last, if attempts at version cause a need for immediate delivery, complications of iatro genic late-preterm delivery generally are not severe. Absolute contraindications to external version are few. It is contraindicated if vaginal delivery is not an option, such as with placenta previa. Another is multifetal gestation. Relative contraindications are early labor, oligohydramnios or rupture of membranes, known nuchal cord, structural uterine abnor malities, fetal-growth restriction, and prior abruption or its risks (Rosman, 2013). While many consider a prior cesarean delivery a contraindication, a few small studies found ECV was not asso ciated with uterine rupture (Burgos, 2014; Keepanasseril, 2017;


Obstentrics_Williams

Obstentrics_Williams. Weill, 2017). At Parkland Hospital, we do not attempt version in these women. More data from clinical studies are needed. Several factors can improve the chances of a successful attempt. These include multiparity, unengaged presenting part, nonanterior placenta, nonobese patient, and abundant amnionic fluid (Kok, 2009, 2011; Velzel, 2015). To augment the last parameter, Burgos and coworkers (2014) administered a preprocedurali2-L intravenous luid bolus. While this improved amnionic luid volume, it did not increase version success rates.


Obstentrics_Williams

Obstentrics_Williams. Patient counseling includes a discussion regarding small but real risks for placental abruption, preterm labor, and fetal compromise. Rarely, uterine rupture, fetomaternal hemorrhage, alloimmunization, amnionic luid embolism, and even death may also complicate attempts at external version. hat said, fetal deaths are rare, serious complication rates are typically very low, and emergent cesarean rates are 0.5 percent or less (Grootscholten, 2008; Rodgers, 2017). And even after successful EC, several reports suggest that the cesarean delivery rate does not completely revert to the baseline for vertex presentations. Specifically, dystocia, malpresentation, and nonreassuring fetal heart patterns may be more common in these fetuses completing successful version (Chan, 2004; de Hundt, 2014; Vezina, 2004).


Obstentrics_Williams

Obstentrics_Williams. ECV should be carried out in an area that has ready access to a facility equipped to perform emergency cesarean delivery (American College of Obstetricians and Gynecologists, 20 16a). Because of the risk for surgical intervention, intravenous access is obtained, and patients abstain from eating for 6 or more hours. Sonographic examination is performed to conirm nonvertex presentation, document amnionic fluid volume adequacy, exclude obvious fetal anomalies if not done previously, and identiy placental location and fetal spine orientation. Preprocedural external monitoring is performed to assess fetal heart rate reactivity. Anti-D immune globulin is given to Rh-D negative women. Tocolysis and regional analgesia may be elected, and rationale for these is provided in subsequent sections.


Obstentrics_Williams

Obstentrics_Williams. he woman is placed in left lateral tilt to aid utero placental perfusion, and Trendelenburg positioning helps during elevation of the breech. During the procedure, we prefer to monitor fetal heart motion sonographically. An abundant abdominal coating of ultrasound gel permits this and also minimizes painful skin friction (Vallikkannu, 2014).


Obstentrics_Williams

Obstentrics_Williams. A forward roll of the fetus usually is attempted first. One or two providers may participate, and one hand grasps the head. he fetal buttocks are then elevated from the maternal pelvis and displaced laterally (Fig. 28-15). The buttocks are then gently guided toward the fundus, while the head is simultaneously directed toward the pelvis. If the forward roll is unsuccessful, a backward flip is attempted. ECV attempts are discontinued for excessive discomfort, persistently abnormal fetal heart rate, or after multiple failed attempts. Failure is not always absolute. Ben-Meir and colleagues (2007) reported a spontaneous version rate of 7 percent among 226 failed versions-2 percent among nulliparas and 13 percent among multiparas.


Obstentrics_Williams

Obstentrics_Williams. If ECV is successful, a nons tress test is repeated until a normal test result is obtained. If version is completed before 39 weeks' gestation, then awaiting spontaneous labor and fetal maturity is preferred. In some studies, immediate labor induction is linked to higher cesarean delivery rates (Burgos, 2015; Kuppens, 2013). FIGURE 28-15 External cephalic version. With an attempted forward roll, clockwise pressure is exerted against the fetal poles.


Obstentrics_Williams

Obstentrics_Williams. To relax the uterus prior to an ECV attempt, existing evidence supports the use of tocolysis (American College of Obstetricians and Gynecologists, 2016a). Most data support the use of the beta-mimetics terbutaline and ritodrine (Cluver, 2015). In one such trial, Fernandez and coworkers (1996) reported that the success rate with subcutaneous terbutaline-52 percentwas significantly higher than without-27 percent. Our policy at Parkland Hospital is to administer 250 I1g of terbutaline subcutaneously to most women before attempted ECV. When maternal tachycardia-a known side efect of terbutaline-is noted, the attempt is begun. Data are limited and, in some cases nonsupportive, for alternate agents that include calciumchannel blockers, such as nifedipine; nitric oxide donors, such as nitroglycerin; the oxytocin-receptor antagonist atosiban; and another betamimetic salbutamol (Burgos, 2010; Hilton, 2009; Kok, 2008; Vani, 2009; Velzel, 2017; Wilcox, 2011).


Obstentrics_Williams

Obstentrics_Williams. Epidural analgesia coupled with tocolysis has been reported to increase version success rates compared with tocolysis alone (Goetzinger, 2011; Magro-Malosso, 2016). Moreover, rates of complications that include fetal heart rate aberrations, emergency cesarean delivery, or placental abruption were not greater with regional analgesia. Of randomized trials, spinal and epidural have both shown success (Khaw, 2015; Weiniger, 2010). Currently, the superior technique and best drugs to administer are unclear. In contrast, from limited data, intravenous sedation does not appear to improve success rates (Burgos, 2016; Khaw, 2015).


Obstentrics_Williams

Obstentrics_Williams. This is a traditional Chinese medicine technique that burns a cigarette-shaped stick of ground Artemisia vugaris-which is also known as mugwort or in Japanese as moxa. At the BL 67 acupuncture point, the stick is directly placed against the skin or indirectly heats an acupuncture needle at the site to increase fetal movement and promote spontaneous breech version (Ewies, 2002). It is performed usually between 33 and 36 weeks' gestation to permit a trial of ECV if not successful. Results from randomized controlled studies are conflicting (Bue, 2016; Coulon, 2014; Coyle, 2012; Sananes, 2016; Vas, 2013). larab M, Regan C, O'Connell MP, et al: Singleton vaginal breech delivery at term: still a safe option. Obstet Gynecol 103:407, 2004 American College of Obstetricians and Gynecologists: External cephalic version. Practice Bulletin No. 161, February 2016a


Obstentrics_Williams

Obstentrics_Williams. American College of Obstetricians and Gynecologists: Mode of term in singleton breech delivery. Committee Opinion No. 340, July 2006, Reairmed 2016b American College of Obstetricians and Gynecologists, Society for MaternalFetal Medicine: Periviable birth. Obstetric Care Consensus No.r6, October 2017 Azria E, Le Meaux JP, Khoshnood B, et al: Factors associated with adverse perinatal outcomes for term breech fetuses with planned vaginal delivery. Am J Obstet Gynecol 207(4):285.e1, 2012 Basak S, Kanungo S, Majhi C: Symphysiotomy: is it obsolete? J Obstet Gynaecol Res 37(7):770,r201r1 Behbehani S, Patenaude V, Abenhaim HA: Maternal risk factors and outcomes of umbilical cord prolapse: a population-based study. J Obstet Gynaecol Can 38(1):23, 2016 Ben-Meir A, Elram T, Tsafrir A, et al: The incidence of spontaneous version after failed external cephalic version. Am J Obstet Gynecol 196(2): 157,200


Obstentrics_Williams

Obstentrics_Williams. Ben-Meir A, Elram T, Tsafrir A, et al: The incidence of spontaneous version after failed external cephalic version. Am J Obstet Gynecol 196(2): 157,200 Bergenhenegouwen LA, Meertens LJ, Schaaf J, et al: Vaginal delivery versus caesarean section in preterm breech delivery: a systematic review. Eur J Obstet Gynecol Reprod Bioi 172: 1, 2014 Bergenhenegouwen L, Vlemmix F, Ensing S, et al: Preterm breech presentation: a comparison of intended vaginal and intended cesarean delivery. Obstet Gynecol 126(6):1223,r2015 Berhan Y, Haileamlak A: he risks of planned vaginal breech delivery versus planned caesarean section for term breech birth: a meta-analysis including observational studies. BJOG 123(1):49,r2016 Biswas A, Johnstone MJ: Term breech delivery: does x-ray pelvimetry help? Aust N ZJ Obstet GynaecoI33:150, 1993


Obstentrics_Williams

Obstentrics_Williams. Biswas A, Johnstone MJ: Term breech delivery: does x-ray pelvimetry help? Aust N ZJ Obstet GynaecoI33:150, 1993 Bogner G, Xu F, Simbrunner C, et al: Single-institute experience, management, success rate, and outcome after external cephalic version at term. Int J Gynaecol Obstet 116(2):134,r2012 Bue L, Lauszus FF: Moxibustion did not have an efect in a randomised clinical trial for version of breech position. Dan Med J 63(2): A5199, 2016 Burgos J, Arana I, Garitano I, et al: Induction oflabor in breech presentation at term: a retrospective cohort study. J Perinat Med 45(3):299, 2017 Burgos J, Eguiguren N, Quintana E, et al: Atosiban vs. ritodrine as a tocolytic in external cephalic version at term: a prospective cohort study. J Perinat Med 38(1):23, 2010 Burgos J, Iglesias M, Pijoan Jr, et al: Probability of cesarean delivery after successful external cephalic version. Int J Gynaecol Obstet 131(2):192,r2015


Obstentrics_Williams

Obstentrics_Williams. Burgos J, Iglesias M, Pijoan Jr, et al: Probability of cesarean delivery after successful external cephalic version. Int J Gynaecol Obstet 131(2):192,r2015 Burgos J, Pijoan JI, Osuna C, et al: Increased pain relief with remifentanil does not improve the success rate of extenal cephalic version: a randomized controlled trial. Acta Obstet Gynecol Scand 95(5):547,r2016 Burgos J, Quintana E, Cobos P, et al: Efect of matenal intravenous Auid therapy on external cephalic version at term: a prospective cohort study. Am J Obstet GynecoI211(6):665.el, 2014 Cammu H, Dony N, Martens G, et al: Common determinants of breech presentation at birth in singletons: a population-based study. Eur J Obstet Gynecol Reprod Bioi 1 : 106, 2014 Canpolat FE, Kose A, Yurdakok M: Bilateral humerus fracture in a neonate after cesarean delivery. Arch Gynecol Obstet 281 (5):967, 2010 Chadha YC, Mahmood T A, Dick MJ, et al: Breech delivery and epidural analgesia. BJOG 99:96, 1992


Obstentrics_Williams

Obstentrics_Williams. Chadha YC, Mahmood T A, Dick MJ, et al: Breech delivery and epidural analgesia. BJOG 99:96, 1992 Chan LY, TangJL, Tsoi KF, et al: Intrapartum cesarean delivery after successful external cephalic version: a meta-analysis. Obstet Gynecolrl04:155, 2004 Chinnock M, Robson S: Obstetric trainees' experience in vaginal breech deliv ery. Obstet Gynecol 110:900, 2007 Cimmino CV, Southworth LE: Persistent hyperextension of the neck in breech ("star-gazing fetus") and in transverse lie ("flying-fetus"): indication for cesar ean section. Am J Roentgenol Radium her Nucl Med , 1975 Cluver C, Gyte GM, Sinclair M, et al: Interventions for helping to turn term breech babies to head irst presentation when using external cephalic version. Cochrane Database Syst Rev 2:CDOOOI84, 2015 Conino E, rsmajovich B, Rudick V, et al: Extradural analgesia in the management of singleton breech delivery. Br J Anaesth 57:892, 1985


Obstentrics_Williams

Obstentrics_Williams. Conino E, rsmajovich B, Rudick V, et al: Extradural analgesia in the management of singleton breech delivery. Br J Anaesth 57:892, 1985 Coulon C, Poleszczuk M, Paty-Montaigne MH, et al: Version of breech fetuses by moxibustion with acupuncture: a randomized controlled trial. Obstet Gynecol 124(1) :32, 2014 Coyle ME, Smith CA, Peat B: Cephalic version by moxibustion for breech presentation. Cochrane Database Syst Rev 5:CD003928, 2012


Obstentrics_Williams

Obstentrics_Williams. Coyle ME, Smith CA, Peat B: Cephalic version by moxibustion for breech presentation. Cochrane Database Syst Rev 5:CD003928, 2012 Deering S, Brown J, Hodor J, et al: Simulation training and resident performance of singleton vaginal breech delivery. Obstet Gynecol (1): 86, 2006 de Hundt M, Velzel J, de Groot C], et al: Mode of delivery after successful external cephalic version: a systematic review and meta-analysis. Obstet Gynecol 123(6):1327,r2014 de Hundt M, Vlemmix F, Bais J M, et l: Risk factors for developmental dysplasia of the hip: a meta-analysis. Eur J Obstet Gynecol Reprod Bioi 165(1):8, 2012 Demirci 0, Tugrul AS, Turgut A, et al: Pregnancy outcomes by mode of delivery among breech births. Arch Gynecol Obstet 285(2):297,r2012 Eide MG, 0yen N, Skjaerven R, et al: Breech delivery and intelligence: a population-based study of8,738 breech infants. Obstet Gynecol 105(1):4, 2005


Obstentrics_Williams

Obstentrics_Williams. Ewies A, Olah KS: he sharp end of medical practice: the use of acupuncture in obstetrics and gynecology. BJOG 109(1): 1, 2002 Fernandez CO, Bloom S, Wendel G: A prospective, randomized, blinded comparison of terbutaline versus placebo for singleton, term external cephalic version. Am J Obstet Gynecol 174:326, 1996 Foad SL, Mehlman CT, Ying J: The epidemiology of neonatal brachial plexus palsy in the United States. J Bone Joint Surg Am 90(6): 1258,2008 Fontenot T, Campbell B, Mitchell-Tun E, et al: Radiographic evaluation of breech presentation: is it necessary? Ultrasound Obstet Gynecol 10:338, 1997 Ford JB, Roberts CL, Nassar N, et al: Recurrence of breech presentation in consecutive pregnancies. BJOG 117(7):830,r2010 Fox AE, Paton RW: he relationship between mode of delivery and developmental dysplasia of the hip in breech infants: a four-year prospective cohort study. J Bone Joint Surg Br 92(12):1695,r2010


Obstentrics_Williams

Obstentrics_Williams. Fox AE, Paton RW: he relationship between mode of delivery and developmental dysplasia of the hip in breech infants: a four-year prospective cohort study. J Bone Joint Surg Br 92(12):1695,r2010 Giuliani A, Scholl WMJ, Basver A, et al: vlode of delivery and outcome of 699 term singleton breech deliveries at a single center. Am J Obstet Gynecol 187: 1694, 2002 Goetzinger KR, Harper LM, Tuuli MG, et al: Efect of regional anesthesia on the success rate of external cephalic version: a systematic review and metaanalysis. Obstet Gynecol 118(5):1137,r2011 Goinet F, Carayol M, Foidart JM, et al: Is planned vaginal delivery for breech presentation at term still an option? Results of an observational prospective srvey in France and Belgium. Am J Obstet Gynecol 194(4): 1002,r2006 Grootscholten K, Kok M, Oei SG, et al: External cephalic version-related risks: a meta-analysis. Obstet Gynecol 112(5): 1143, 2008


Obstentrics_Williams

Obstentrics_Williams. Grootscholten K, Kok M, Oei SG, et al: External cephalic version-related risks: a meta-analysis. Obstet Gynecol 112(5): 1143, 2008 Hannah ME, Hannah WJ, Hewson SA, et al: Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Lancet 356:1375,r2000 Hartnack 111arin JE, Rasmussen S, Krebs L: Consequences of the Term Breech Trial in Denmark. Acta Obstet Gynecol Scand ):767,r201r1 Henandez-Marti M, Dal Canto MC, Kidd JM: Evidence of spinal cord injury in an infant delivered by cesarean section. A case report. Childs Brain 11(3):197,r1984


Obstentrics_Williams

Obstentrics_Williams. Henandez-Marti M, Dal Canto MC, Kidd JM: Evidence of spinal cord injury in an infant delivered by cesarean section. A case report. Childs Brain 11(3):197,r1984 Hilton J, Allan B, Swaby C, et al: Intravenous nitroglycerin for external cephalic version: a randomized controlled trial. Obstet Gynecol 114(3):560, 2009 Hofmann J, Thomassen K, Stumpp P, et al: New MRI criteria for successful vaginal breech delivery in primiparae. PLoS One 11(8):eOI61028, 2016 Hofmeyr GJ, Hannah M, Lawrie TA: Planned caesarean section for term breech delivery. Cochrane Database SYSt Rev :CDOOO 166, 2015a Hofmeyr GJ, Kulier R, West HM: Extenal cephalic version for breech presentation at term. Cochrane Database Syst Rev 4:CD000083, 201r5b Hofmeyr GJ, Shweni PM: Symphysiotomy for feto-peh-ic disproportion. Cochrane Database Syst Rev 10:CD005299, 2012


Obstentrics_Williams

Obstentrics_Williams. Hofmeyr GJ, Shweni PM: Symphysiotomy for feto-peh-ic disproportion. Cochrane Database Syst Rev 10:CD005299, 2012 Janiat A, Eluard V, Martz 0, et al: Induced labour at term and breech presentation: Experience of a level lIB French maternity. J Gynecol Obstet Hum Reprod 46(7):597, 201 Kayem G, Com baud V, Lorthe E, et al: Mortality and morbidity in early preterm breech singletons: impact of a policy of planned vaginal delivelY. Eur J Obstet Gynecol Reprod Bioi 192:61, 2015 Keepanasseril A, Anand K, Soundara Raghavan S: Matched cohort study of external cephalic version in women with previous cesarean delivery. Int J Gynaecol Obstet 9,r2017 Khaw KS, Lee SW, Ngan Kee WD, et al: Randomized trial of anaesthetic interventions in external cephalic version for breech presentation. Br J Anaesth 114(6):944,r2015 Kok M, Bais JM, van Lith JM, et al: Nifedipine as a uterine relaxant for external cephalic version: a randomized controlled trial. Obstet Gynecol 112(2 Pt 1):271,r2008


Obstentrics_Williams

Obstentrics_Williams. Kok M, Bais JM, van Lith JM, et al: Nifedipine as a uterine relaxant for external cephalic version: a randomized controlled trial. Obstet Gynecol 112(2 Pt 1):271,r2008 Kok M, Cnossen J, Gravendeel L, et al: Ultrasound factors to predict the orcome of external cephalic version: a meta-analysis. Ultrasound Obstet Gynecol 33(1):76, 2009 Kok M, van der Steeg JW, van der Post JA, et al: Prediction of success of external cephalic version after 36 weeks. Am J Perinatol 28(2): 103, 2011 Kotaska A, Menticoglou S, Gagnon R: SOGC clinical practice guideline: vaginal delivery of breech presentation: No. 226, June 2009. Int J Gynaecol Obstet 107(2):169,r2009 Kuppens SM, Hurron EK, Hasaart TH, et al: Mode of delivery following successful external cephalic version: comparison with spontaneous cephalic presentations at delivery. J Obstet Gynaecol Can 35(10):883, 2013


Obstentrics_Williams

Obstentrics_Williams. Lamrani YA, Maaroui M, Kamaoui I, et al: Neonatal distal femoral epiphyseal dislocation: an ultrasound diagnosis. J Med Ultrason 38(4):221, 2011 Lennox CE, Kwast BE, Farley TM: Breech labor on the WHO partograph. Int J Gynaecol Obstet 62(2): , 1998 Lumbiganon P, Laopaiboon M, Gulmezoglu M, et al: Method of delivelY and pregnancy ourcomes in Asia: the WHO global survey on maternal and perinatal health 2007-08. Lancet 375(9713):490,r2010 Lydon-Rochelle M, Albers L, GorwodaJ, et al: Accracy of Leopold maneuvers in screening for malpresentation: a prospective study. Birth 20:132, 1993 Lyons J, Pressey T, Bartholomew S, et al: Delivery of breech presentation at term gestation in Canada, 2003-201 1. Obstet GynecoIr125(5):1153, 2015 Macharey G, Gissler M, Rahkonen L, et al: Breech presentation at term and associated obstetric risks factors-a nationwide population based cohort study. Arch Gynecol Obstet 295(4):833,r2017


Obstentrics_Williams

Obstentrics_Williams. Macharey G, Gissler M, Rahkonen L, et al: Breech presentation at term and associated obstetric risks factors-a nationwide population based cohort study. Arch Gynecol Obstet 295(4):833,r2017 Macharey G, Ulander VM, Heinonen S, et al: Induction of labor in breech presentations at term: a retrospective observational study. Arch Gynecol Obstet 293(3):549,r2016 Magro-Malosso ER, Saccone G, Di Tommaso M, et al: Neuraxial analgesia to increase the success rate of external cephalic version: a systematic review and meta-analysis of randomized controlled trials. Am J Obstet Gynecol 215(3):276,r2016 Marzouk P, Arnaud E, Oury JF, et al: Induction of labour and breech presentation: experience of a French maternity ward. [French]. J Gynecol Obstet Bioi Reprod (Paris) 40(7):668, 2011 Maslovitz S, Barkai G, Lessing JB, et al: Recurrent obstetric management mistakes identiied by simulation. Obstet Gynecol 109(6): 1295, 2007


Obstentrics_Williams

Obstentrics_Williams. Maslovitz S, Barkai G, Lessing JB, et al: Recurrent obstetric management mistakes identiied by simulation. Obstet Gynecol 109(6): 1295, 2007 Matsubara S, Izumi A, Nagai T, et al: Femur fracture during abdominal breech delivery. Arch Gynecol Obstet 278(2):195,r2008 McNamaraJM, Odibo AO, Macones GA, et al: The efect of breech presentation on the accuracy of estimated fetal weight. Am J PerinatoIr29(5):353, 2012 Michel S, Drain A, Closset E, et al: Evaluation of a decision protocol for type of delivery of infants in breech presentation at term. Eur J Obstet Gynecol Reprod Bioi 158(2):194, 2011 Mostello 0, Chang JJ, Bai F, et al: Breech presentation at delivery: a marker for congenital anomaly? J Perinatol 34(1): 11, 2014 Muhuri PK, Macdorman MF, Menacker F: Method of delivery and neonatal mortaliry among very low birth weight infants in the United States. Matern Child Health J 10:47,r2006


Obstentrics_Williams

Obstentrics_Williams. Muhuri PK, Macdorman MF, Menacker F: Method of delivery and neonatal mortaliry among very low birth weight infants in the United States. Matern Child Health J 10:47,r2006 Nassar N, Roberts CL, Cameron CA, et al: Diagnostic accuracy of clinical examination for detection of non-cephalic presentation in late pregnancy: cross sectional analytic study. BMJ 333:578, 2006 Obeidat N, Zayed F, Alchalabi H, et al: Umbilical cord prolapse: a lO-year retrospective study in two civil hospitals, North Jordan. J Obstet Gynaecol 30(3):257,r2010 Ortiz-Neira CL, Paolucci EO, Donnon T: A meta-analysis of common risk factors associated with the diagnosis of developmental dysplasia of the hip in newborns. Eur J RadioIr81(3):e344, 2012 Phelan JP, Bethel M, DeVore G, et al: Use of ultrasonography in the breech presentation with hyperextension of the fetal head. J Ultrasound Med 2(8):373, 1983 Pinard A: On version by external maneuvers. In Traite du Palper Abdominal. Paris, Lauwereyns, 1889


Obstentrics_Williams

Obstentrics_Williams. Raju TN, Mercer BM, Burchfield OJ, et al: Periviable birth: executive summary of a joint workshop by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Society for Maternal-Fetal Medicine, American Academy of Pediatrics, and merican College of Obstetricians and Gynecologists. Obstet GynecoIr123(5):1083, 2014 Reddy UM, Zhang J, Sun L, et al: Neonatal mortality by attempted route of delivery in early preterm birth. Am J Obstet Gynecol 207(2): 117.e1, 2012 Rietberg CC, Elferink-Stinkens PM, Visser GH: The efect of the Term Breech Trial on medical intervention behaviour and neonatal outcome in he Netherlands: an analysis of35,453 term breech infants. BJOG 112(2):205,r2005 Rodgers R, Beik N, Nassar N, et al: Complications of external cephalic version: a retrospective analysis of 1121 patients at a tertiary hospital in Sydney. BJOG 124(5):767,r201 Rojansky N, Tanos V, Lewin A, et al: Sonographic evaluation of fetal head extension and maternal pelvis in


Obstentrics_Williams

Obstentrics_Williams. analysis of 1121 patients at a tertiary hospital in Sydney. BJOG 124(5):767,r201 Rojansky N, Tanos V, Lewin A, et al: Sonographic evaluation of fetal head extension and maternal pelvis in cases of breech presentation. Acta Obstet Gynecol Scand 73:607, 1994 Roman H, Carayol M, Watier L, et al: Planned vaginal delivery of fetuses in breech presentation at term: prenatal determinants predictive of elevated risk of cesarean delivery during labor. Eur J Obstet Gynecol Reprod Bioi 138(1):14,r2008


Obstentrics_Williams

Obstentrics_Williams. Rosman AN, Guijt A, Vlemmix F, et al: Contraindications for external cephalic version in breech position at term: a systematic review. Acta Obstet Gynecol Scand 92(2):137,r2013 Royal College of Obstetricians and Gynaecologists: he management of breech presentation. RCOG Green Top Guidelines, No. 20b. London, 2006 Sananes N, Roth GE, issi GA, et al: Acupuncture version of breech presentation: a randomized sham-controlled single-blinded trial. Eur J Obstet Gynecol Reprod Bioi 204:24, 2016 Sandberg EC: The Zavanelli maneuver: 12 years of recorded experience. Obstet GynecoIr93:312, 1999


Obstentrics_Williams

Obstentrics_Williams. Sandberg EC: he Zavanelli maneuver extended: progression of a revolutionary concept. AmJ Obstet Gynecolr158(6 Pt 1):1347,r1988 Saroha M, Batra P, Dewan P, et al: Genital injuries in neonates following breech presentation. J Neonatal Perinatal Med 8(4):421, 2015 Schutte JM, Steegers A, Santema JG, et al: Maternal deaths after elective cesarean section for breech presentation in the Netherlands. Acta Obstet Gynecol Scand 86(2):240, 2007 Sherer OM, Menashe M, Palti Z, et al: Radiologic evidence of a nuchal arm in the breech-presenting fetus at the onset of labor: an indication for abdominal delivery. Am J PerinatoI6(3):353, 1989


Obstentrics_Williams

Obstentrics_Williams. Steyn W, Pieper C: Favorable neonatal outcome after fetal entrapment and partially successful Zavanelli maneuver in a case of breech presentation. Am J Perinatolrll:348, 1994 Sunday-Adeoye 1M, Okonta P, Twomey 0: Symphysiotomy at the Mater Misericordiae Hospital Afikpo, Ebonyi State of Nigeria (1982-1999): a review of 1013 cases. J Obstet GynaecoI24(5):525, 2004 Thomas PE, Petersen SG, Gibbons K: he influence of mode of birth on neonatal survival and maternal outcomes at extreme prematurity: a retrospective cohort study. Aust N Z J Obstet Gynaecol 56(1):60, 2016 homas SM, Bees NR, Adam EJ: Trends in the use of pelvimetry techniques. Clin RadioIr53(4):293, 1998 Toivonen E, Palomaki 0, Huhtala H, et al: Selective vaginal breech delivery at term-still an option. Acta Obstet Gynecol Scand 91 (10): 1177, 2012 Vallikannu N, Nadzratulaiman N, Omar SZ, et al: Talcum powder or aqueous gel to aid external cephalic version: a randomised controlled trial. BMC Pregnancy Childbirth 14:49,2014


Obstentrics_Williams

Obstentrics_Williams. Vallikannu N, Nadzratulaiman N, Omar SZ, et al: Talcum powder or aqueous gel to aid external cephalic version: a randomised controlled trial. BMC Pregnancy Childbirth 14:49,2014 Vani S, Lau SY, Lim BK, et al: Intravenous salbutamol for external cephalic version. Int J Gynecol Obstet 104(1):28, 2009 Vas J, Aranda-Regules JM, Modesto M, et al: Using moxibustion in primary healthcare to correct non-vertex presentation: a multicentre randomised controlled trial. Acupunct Med 31(1):31,r2013 Velzel J, Vlemmix F, Opmeer Be, et al: Atosiban versus fenoterol as a uterine relaxant for external cephalic version: a randomised controlled trial. BMJ 26:356,r2017 Velzel J, de Hundt M, Mulder FM, et al: Prediction models for successful external cephalic version: a systematic review. Eur J Obstet Gynecol Reprod BioI 195:160,r2015


Obstentrics_Williams

Obstentrics_Williams. Vendittelli F, Pons Je, Lemery 0, et al: he term breech presentation: neonatal results and obstetric practices in France. Eur J Obstet Gynecol Reprod BioI 125(2):176,r2006 Vezina Y, Bujold E, Varin J, et al: Cesarean delivery after successful external cephalic version of breech presentation at term: a comparative study. Am J Obstet Gynecol 190:763,r2004 Vialle R, Pietin-Vialle C, Ilharreborde B, et al: Spinal cord injuries at birth: a multicenter review of nine cases. J Matern Fetal Neonatal Med 20(6):435, 2007 Vistad I, Klungs0yr K, Albrechtsen S, et al: Neonatal outcome of singleton term breech deliveries in N otway from 1991 to 2011. Acta Obstet Gynecol Scand 94(9):997, 2015


Obstentrics_Williams

Obstentrics_Williams. Weill Y, Pollack N: he eicacy and safery of external cephalic version after a previous caesarean delivery. Aust N Z J Obstet Gynaecol 57(3):323, 2017 Weiniger CF, Ginosar Y, Elchalal U, et al: Randomized controlled trial of external cephalic version in term multiparae with or without spinal analgesia. Br J Anaesth 104(5):613,r2010 Wery E, Le Roch A, Subtil 0: Zavanelli maneuver performed in a breech presentation. Int J Gynaecol Obstet 120(2):193,2013 Westgren M, Grundsell H, Ingemarsson I, et al: Hyperextension of the fetal head in breech presentation. A study with long-term follow-up. BJOG 88(2):101, 1981 Whyte H, Hannah ME, Saigal S, et al: Outcomes of children at 2 years after planned cesarean birth versus planned vaginal birth for breech presentation at term: the International Randomized Term Breech Trial. Am J Obstet GynecoIr191(3):864,r2004 Wilcox CB, Nassar N, RobertS CL: Efectiveness of nifedipine tocolysis to facilitate external cephalic version: a systematic review. BJOG


Obstentrics_Williams

Obstentrics_Williams. Term Breech Trial. Am J Obstet GynecoIr191(3):864,r2004 Wilcox CB, Nassar N, RobertS CL: Efectiveness of nifedipine tocolysis to facilitate external cephalic version: a systematic review. BJOG 118(4):423,2011 Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hofman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hill Education, 2017


Obstentrics_Williams

Obstentrics_Williams. The most important function of orceps is traction exercised or the purpose of drawing the head through the genital tract. In not a ew cases, however, particulary in occipito-posterior presentations, its employment as a rotator is attended by most happy results. -J. Whitridge Williams (1903) Operative deliveries are vaginal deliveries accomplished with the use of forceps or a vacuum device. Once either is applied to the fetal head, outward traction generates forces that augment maternal pushing to deliver the fetus vaginally. he most important function of both devices is traction. In addition, forceps may also be used for rotation, particularly from occiput transverse and posterior positions.


Obstentrics_Williams

Obstentrics_Williams. According to the birth certiicate data from the National Vital Statistics Report, forceps-or vacuum-assisted vaginal delivery was used for 3.2 percent of births in the United States in 2014. his is a decline from 9.0 percent in 1990 (Hamilton, 2015). For these deliveries, a vacuum is disproportionately selected, and the vacuum-to-forceps delivery ratio is nearly 5: 1 (Merriam, 2017). In general, most of these attempts are successful. In 2006, only 0.4 percent of forceps trials in the United States and 0.8 percent of vacuum extraction attempts failed to result in vaginal delivery (Osterman, 2009).


Obstentrics_Williams

Obstentrics_Williams. If it is technically feasible and can be safely accomplished, termination of second-stage labor by traction instruments is indicated in any condition threatening the mother or fetus that is likely to be relieved by delivery. Some fetal indications include nonreassuring fetal heart rate pattern and premature placental separation (Schuit, 2012). In the past, forceps delivery was believed to be somewhat protective of the fragile preterm infant head. However, outcomes for neonates who 500 to 1500 g do not signiicantly difer if delivered spontaneously or by outlet forceps (Fairweather, 1981; Schwartz, 1983).


Obstentrics_Williams

Obstentrics_Williams. Some maternal indications include heart disease, pulmonary compromise, intrapartum infection, and certain neurological conditions. The most common are exhaustion and prolonged second-stage labor. However, a speciic maximum length beyond which all women should be considered for operative vaginal delivery has not been identiied (American College of Obstetricians and Gynecologists, 2016). Operative delivery is generally performed from either a low or outlet station. Additionally, forceps or vacuum delivery should not be used electivey until the criteria for an outlet delivery have been met. In these circumstances, operative delivery is a simple and safe operation, although with some risk of maternal lower reproductive tract injury (Yancey, 1999). Classiication for operative vaginal delivery is summarized in Table It emphasizes that the two most important discriminators of risk for both mother and neonate are station and rotation. Station is measured in centimeters, -5 to 0 to +5.


Obstentrics_Williams

Obstentrics_Williams. It emphasizes that the two most important discriminators of risk for both mother and neonate are station and rotation. Station is measured in centimeters, -5 to 0 to +5. TABLE 29-' . Operative Vaginal Delivery Prerequisites and Classification According to Station and Rotationa Outlet forceps Scalp is visible at the introitus without separating the labia Fetal head is at or on perineum Head is OA or OP or Head is right or left OA or OP position but rotation ;45 degrees Low forceps (2 types) Leading point offetal skull is at station �+2 cm, and not on the pelvic floor, and: aClassification for the vacuum delivery system is the same as forforceps except that vacuum is used for traction but not rotation. bForceps, but not vacuum extractor, may be used for delivery of a face presentation with mentum anterior. (Piper forceps may be used to deliver the head during breech delivery.


Obstentrics_Williams

Obstentrics_Williams. (Piper forceps may be used to deliver the head during breech delivery. Zero station relects a line drawn between the ischial spines. Deliveries are categorized as outlet, low, and midpelvic procedures. High orceps, in which instruments are applied above 0 station, have noplace in contemporay obstetrics. Once station and rotation are assessed, several prerequisites are met and are listed in Table 29-1. For vacuum extraction, fetuses should also be at least 34 weeks' gestation, and although infrequently used in the United States, fetal scalp blood sampling should not have been recently performed. Of requisites, ascertaining correct head position is essential, and the anatomy of the fetal skull is described in Figure In unclear cases, sonography is useful to identiy fetal orbits and nasal bridge to aid orientation (Malvasi, 2014). occiput posterior; OVD operative vaginal delivery.


Obstentrics_Williams

Obstentrics_Williams. In unclear cases, sonography is useful to identiy fetal orbits and nasal bridge to aid orientation (Malvasi, 2014). occiput posterior; OVD operative vaginal delivery. Regional analgesia or general anesthesia is preferable for low forceps or midpelvic procedures, although pudendal blockade may prove adequate for outlet forceps. As discussed in Chapter 25 (p. 495), regional analgesia during labor does not appear to increase the risk for operative delivery (Halpern, 2004; Marucci, 2007; Wassen, 2014). The bladder is emptied to provide additional pelvic space and minimize bladder trauma. Urinary retention and bladder dysunction are oten short-term efects offorceps and vacuum deliveries (Mulder, 2012; Pifarotti, 2014). Notably, episiotomy and epidural analgesia, both common associates, are also identified risks for urinary retention. Symptoms are brief and typically resolve with 24 to 48 hours ofpassive Foley catheter bladder drainage. Biparietal diam.eter = 9.5 cm


Obstentrics_Williams

Obstentrics_Williams. Biparietal diam.eter = 9.5 cm Coronal suture --=./ FIGURE 29-1 Fetal head (A, B) at term showing fontanels, sutures, and various dimensions. There is an increased risk of certain morbidities for both mother and fetus when operative delivery is employed. In general, these are related to the ease with which the delivery is accomplished.


Obstentrics_Williams

Obstentrics_Williams. There is an increased risk of certain morbidities for both mother and fetus when operative delivery is employed. In general, these are related to the ease with which the delivery is accomplished. In general, a higher station and/or greater degrees of rotation increase the chance of maternal or fetal injury. Morbidity is most properly compared with morbidity from cesarean delivery, and not with that from spontaneous vaginal delivery. his is the most appropriate comparator because the alternative to indicated operative delivery is cesarean delivery. For example, postpartum wound or uterine infection is more frequent in women following cesarean compared with operative vaginal delivery (Bailit, 2016; Halscott, 2015). Moreover, in a study of more than 1 million births, Spiliopoulos and associates (201i1) reported cesarean delivery, but not operative vaginal delivery, as a risk for peripartum hysterectomy.


Obstentrics_Williams

Obstentrics_Williams. he very conditions that lead to indications for operative delivery also increase the need for episiotomy and the likelihood of lacerations (de Leeuw, 2008). That said, forceps and vacuum deliveries are associated with higher rates of third-and fourthdegree lacerations as well s vaginal wall and cervical lacerations (Gurol-Urganci, 2013; Hirayama, 2012; Landy, 2011; Pergialiotis, 2014). These appear to occur more frequently with forceps compared with vacuum extraction, and especially if there is a midline episiotomy (Kudish, 2006; O'Mahony, 2010). Hagadorn-Freathy and coworkers (1991) reported a 13-percent rate of third-and fourth-degree episiotomy extensions and vaginal lacerations for outlet forceps, 22 percent for low forceps with less than 45-degree rotation, 44 percent for low forceps with more than 45-degree rotation, and 37 percent for midforceps deliveries.


Obstentrics_Williams

Obstentrics_Williams. In an efort to lower rates of third-and fourth-degree lacerations, and coincident with overall eforts to reduce routine episiotomy use, many advocate only indicated episiotomy with operative delivery. If episiotomy is required, a protective efect against these more extensive perineal lacerations may be aforded by mediolateral episiotomy (de Leeuw, 2008; de Vogel, 2012; Hirsch, 2008). Early disarticulation of forceps and cessation of maternal pushing during disarticulation can also be protective. Last, these injuries are more common with an occiput posterior position (Damron, 2004). Thus, manual or forceps rotation to an occiput anterior position and then subsequent traction delivery may decrease rates oflower reproductive tract injury (Bradley, 2013).


Obstentrics_Williams

Obstentrics_Williams. his term encompasses urinary incontinence, anal incontinence, and pelvic organ prolapse. Operative vaginal delivery has been suggested as a possible risk for each of these. Proposed mechanisms include structural compromise and/or pelvic loor denervation secondary to forces exerted during delivery. Parity and speciically vaginal delivery are risk factors for urinary incontinence (Gyhagen, 2013; Rortveit, 2003). But, many studies do not support an increased risk compared with vaginal delivery alone (Gartland, 2016; Leijonhuvud, 2011; MacArthur, 2016; Tahtinen, 2016).


Obstentrics_Williams

Obstentrics_Williams. MacArthur, 2016; Tahtinen, 2016). Evidence linking anal incontinence with operative vaginal delivery is conlicting. Some studies show that anal sphincter disruption caused by higher-order episiotomy, but not delivery mode, is the main etiological factor strongly associated with anal incontinence (BoIs, 2010; Evers, 2012; Nygaard, 1997). In con trast, others directly link operative delivery with this complica tion (Dolan, 2010; Marthur, 2013). But, these studies may not be incongruous-recall that operative delivery is associated with increased rates of higher-order episiotomy. Importantly, several studies and reviews have not found cesarean delivery to be protec tive for anal incontinence (Nelson, 2010). Last, evidence linking pelvic organ prolapse with operative delivery also indicates mixed results (Gyhagen, 2013; Handa, 2012; Vo1l0yhaug, 2015).


Obstentrics_Williams

Obstentrics_Williams. hese injuries are more frequent with operative vaginal delivery than with cesarean delivery or spontaneous vaginal delivery. Injuries may be seen with either method. hey are more common with vacuum extraction, and types associated with this device include cephalohematoma, subgaleal hemorrhage, retinal hemorrhage, neonatal jaundice secondary to these hemorrhages, shoulder dystocia, clavicular fracture, and scalp lacerations. Cephalohematoma and subgaleal hemorrhage are both extracranial lesions described in Chapter 33 (p. 628). Forceps-assisted vaginal delivery has higher rates of facial nerve injury, brachial plexus injury, depressed skull fracture, and corneal abrasion (merican College of Obstetricians and Gynecologists, 2015; Demissie, 2004; Dupuis, 2005). For intracranial hemorrhage, some studies have associated vacuum extraction with higher rates, whereas others show similar rates with either of the two methods (Towner, 1999; Wen, 2001; Werner, 201l).


Obstentrics_Williams

Obstentrics_Williams. Comparing operative vaginal with cesarean delivery, rates of extracranial hematoma, skull fracture, facial nerve or brachial plexus injury, retinal hemorrhage, and facial or scalp laceration are lower with cesarean deliveY, and shoulder dystocia is eliminated. Importantly, however, fetal acidemia rates are not increased with operative delivery (Contag, 2010; Walsh, 2013). Intracranial hemorrhage rates are similar among newborns delivered by vacuum extraction, forceps, or cesarean delivery during labor (Towner, 1999). But, these rates are higher than among those delivered spontaneously or by cesarean delivery before labor. These authors suggest that the common risk factor for intracranial hemorrhage is abnormal labor. Werner and associates (2011), in their evaluation of more than 150,000 singleton deliveries, reported that forceps-assisted delivery was associated with fewer total neurological complications compared with vacuum-assisted or cesarean delivery. However, as a subset,


Obstentrics_Williams

Obstentrics_Williams. singleton deliveries, reported that forceps-assisted delivery was associated with fewer total neurological complications compared with vacuum-assisted or cesarean delivery. However, as a subset, subdural hemorrhage was signiicantly more frequent in both instrumental cohorts compared with neonates in the cesarean delivery group.


Obstentrics_Williams

Obstentrics_Williams. Comparing rotational operative delivery and second-stage cesarean delivery, maternal and neonatal morbidity rates are similar (Aiken, 2015; Bahl, 2013; Stock, 2013). For example, in their large series, Tempest and associates (2013) found similar morbidity rates among malpositioned fetuses during second-stage labor that underwent Kielland rotation, rotational vacuum extraction, or emergency cesarean delivery.


Obstentrics_Williams

Obstentrics_Williams. Comparing midforceps and cesarean delivery, reports of neonatal morbidity rates are from older studies and are conflicting. In the study by Towner and colleagues (1999), similar risks were reported for intracranial hemorrhage. Bashore and associates (1990) observed comparable Apgar scores, cord blood acid-base values, neonatal intensive care unit admission, and birth trauma between these two. In another study, however, Robertson and coworkers (1990) reported signiicantly higher rates of these adverse outcomes in the midforceps group. Hagadorn-Freathy and colleagues (1991) reported an increased risk for facial nerve palsy-9 percent-with midforceps delivery. In a recent report comparing low and midforceps procedures, Ducarme and coworkers (2015) found comparable morbidity rates.


Obstentrics_Williams

Obstentrics_Williams. Mechanisms of Acute Injury he types of fetal injury with operative delivery can usually be explained by the forces exerted. In cases of cephalohematoma or subgaleal hemorrhage, suction and perhaps rotation during vacuum extraction may lead to a primary vessel laceration. Intracranial hemorrhage may result from skull fracture and vessel laceration or from vessel laceration alone due to exerted forces. With facial nerve palsy, one of the forceps blades may compress the nerve against the facial bones. he higher rates of shoulder dystocia seen with vacuum extraction may result from the angle of traction. With the vacuum, this angle creates vector forces that actually pull the anterior shoulder into the symphysis pubis (Caughey, 2005). To explain brachial plexus injury, Towner and Ciotti (2007) proposed that as the fetal head descends down the birth canal, the shoulders may stay above the pelvic inlet. Thus, similar to shoulder dystocia at the symphysis, this "shoulder dystocia at the


Obstentrics_Williams

Obstentrics_Williams. proposed that as the fetal head descends down the birth canal, the shoulders may stay above the pelvic inlet. Thus, similar to shoulder dystocia at the symphysis, this "shoulder dystocia at the pelvic inlet" is overcome by traction forces but with concomitant stretch on the brachial plexus.


Obstentrics_Williams

Obstentrics_Williams. Evidence regarding long-term neurodevelopmental outcomes in children born by operative delivery is reassuring. In an older study, Seidman and colleagues (1991) evaluated more than 52,000 Israeli Defense Forces dratees at age 17 years and found that regardless of delivery mode, rates of physical or cognitive impairments were similar. Wesley and associates (1992) noted similar intelligence scores among 5-year-olds following spontaneous, forceps, or vacuum deliveries. Murphy and coworkers (2004) found no association between forceps delivery and epilepsy in a cohort of more than 21,000 adults. In their epidemiological review, O'Callaghan and colleagues (2011) found no association between cerebral palsy and operative delivery. Last, Bahl and associates (2007) noted that the incidence of neurodevelopmental morbidity was similar in those undergoing successul forceps delivery, failed forceps with cesarean delivery, or cesarean delivery without forceps.


Obstentrics_Williams

Obstentrics_Williams. Data regarding midforceps deliveries are for the most part reassuring. Broman and coworkers (1975) reported that infants delivered by midforceps had slightly higher intelligence scores at age 4 years compared with those of children delivered spontaneously. Using the same database, however, Friedman and associates (1977, 1984) analyzed intelligence scores at or after age 7 years. They concluded that children delivered by midforceps had lower mean intelligence quotients compared with those delivered by outlet forceps. In yet another report from this database, Dierker and colleagues (1986) compared long-term outcomes of children delivered by midforceps with those delivered by cesarean after dystocia. he strength of this study is the appropriateness of the control group. hese investigators reported that delivery by midforceps was not associated with neurodevelopmental disability. Last, Nilsen (1984) evaluated 18-year-old men and found that those delivered by Kielland forceps had higher


Obstentrics_Williams

Obstentrics_Williams. reported that delivery by midforceps was not associated with neurodevelopmental disability. Last, Nilsen (1984) evaluated 18-year-old men and found that those delivered by Kielland forceps had higher intelligence scores than those delivered spontaneously, by vacuum extraction, or by cesarean.


Obstentrics_Williams

Obstentrics_Williams. If an attempt to perform an operative delivery is expected to be diicult, then it should be considered a trial. Moving the woman to an operating room for this attempt, which could be followed by immediate cesarean delivery if operative delivery fails, has merit. If forceps cannot be satisfactorily applied, then the procedure is stopped and either vacuum extraction or cesarean delivery is performed. With the former, if the fetus does not descend with traction, the trial should be abandoned and cesarean delivery performed.


Obstentrics_Williams

Obstentrics_Williams. With such caveats, cesarean delivery after an attempt at operative vaginal delivery was not associated with adverse neonatal outcomes if there was a reassuring fetal heart rate tracing (Alexander, 2009). A similar study evaluated 122 women who had a trial of midcavity forceps or vacuum extraction in a setting with full preparations for cesarean delivery (Lowe, 1987). Investigators found no significant diference in immediate neonatal or maternal morbidity compared with that of 42 women delivered for similar indications by cesarean but without such a trial. Conversely, in 61 women who had "unexpected" vacuum or forceps failure in which there was no prior preparation for immediate cesarean delivery, neonatal morbidity was higher.


Obstentrics_Williams

Obstentrics_Williams. Some factors associated with operative delivery failure are persistent occiput posterior position and birthweight >4000 g (Ben-Haroush, 2007; Verhoeven, 2016). However, Palatnik and associates (2016) found that risk factors poorly predicted success. In general, to avert morbidity with failed forceps or vacuum delivery, the American College of Obstetricians and Gynecologists (2015) cautions that these trials should be attempted only if the clinical assessment suggests a successful outcome. We also emphasize proper training.


Obstentrics_Williams

Obstentrics_Williams. Sequential instrumentation most often involves an attempt at vacuum extraction followed by one with forceps. his most likely stems from the higher completion rate with forceps compared with vacuum extraction noted earlier. This practice significantly increases risks for fetal trauma (Dupuis, 2005; Gardella, 2001; Murphy, 2011). Because of these adverse outcomes, the American College of Obstetricians and Gynecologists (2015) recommends against the sequential use of instruments unless there is a "compelling and justifiable reason." As the rate of operative vaginal delivery has declined, so have opportunities for training (Fitzwater, 2015; Kyser, 2014). In FIGURE 29-2 Simpson forceps have fenestrated blades, parallel shanks, and English lock. The cephalic curve accommodates the fetal head.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 29-2 Simpson forceps have fenestrated blades, parallel shanks, and English lock. The cephalic curve accommodates the fetal head. many programs, training in even low and outlet forceps proce dures has reached critically low levels. For residents completing training in 2015, the Accreditation Council for Graduate Med ical Education reported a median of only five forceps deliveries, and that for vacuum deliveries was 16.


Obstentrics_Williams

Obstentrics_Williams. Because traditional hands-on training has evolved, residency programs should have readily available skilled operators to teach these procedures by simulation as well as through actual cases (Skinner, 2017; Spong, 2012). And, the efectiveness of simulation training has been reported (Dupuis, 2006, 2009; Leslie, 2005). In one program, maternal and neonatal morbidity rates with operative delivery decreased after the implementation of a formal education program that included a manikin and pelvic model (Cheong, 2004). In another, a 59-percent increase in forceps deliveries over 2 years was related to a single experienced and proactive instructor assigned to teach forceps to residents in labor and delivery (Solt, 2011).


Obstentrics_Williams

Obstentrics_Williams. Forceps refers to the paired instrument, and each member of this pair is called a branch. Branches are designated left or right according to the side of the maternal pelvis to which they are applied (Fig. 29-2). Each branch has four components: blade, shank, lock, and handle (Fig. 29-3). Each blade has a toe, a heel, and two curves. Of these, the outward cephalic curve conforms to the round fetal head, whereas the upward pelvic curve corresponds more or less to the curve of the birth canal. Some blades have an opening within or a depression along the blade surface and are termed enestrated or pseudoenestrated, respectively. True fenestration reduces the degree of head slippage during forceps rotation. Disadvantageously, it can increase friction between the blade and vaginal wall. With pseudo fenestration, the forceps blade is smooth on the outer maternal side but indented on the inner fetal surface. he goal is to reduce head slipping yet improve the ease and safety of application and


Obstentrics_Williams

Obstentrics_Williams. fenestration, the forceps blade is smooth on the outer maternal side but indented on the inner fetal surface. he goal is to reduce head slipping yet improve the ease and safety of application and removal of forceps compared with pure fenestrated blades. In general, fenestrated blades are used for a fetus with a molded head or for rotation. In most situations, however, despite these subtle diferences any are appropriate.


Obstentrics_Williams

Obstentrics_Williams. he blades are connected to shanks, which may be parallel or overlapping. Locks are found on all forceps and help to connect FIGURE 29-3 Luikart forceps have pseudofenestrated blades, overlapping shanks, sliding lock, tongue groove handles. The pelvic curve is marked in this example by the black line. the right and left branches and stabilize the instrument. They can be located at the end of the shank nearest to the handles (English lock), at the ends of the handles (pivot lock), or along the shank (sliding lock). Although varied in design, handles, when squeezed, raise compression forces against the fetal head. hus, forces to consider include traction and compression.


Obstentrics_Williams

Obstentrics_Williams. Forceps blades grasp the head and are applied according to fetal head position. If the head is in an occiput anterior (OA) position, two or more fingers of the right hand are introduced inside the left posterior portion of the vulva and then into the vagina beside the fetal head. he handle of the left branch is grasped between the thumb and two fingers of the left hand (Fig. 29-4). FIGURE 29-4 For OA or LOA positions, the left handle of the forceps is held in the left hand. The blade is introduced into the left side of the pelvis between the fetal head and the fingers of the operator's right hand. FIGURE 29-5 Insertion arc of the blade. Importantly, the thumb of the right hand, guides the blade during placement, as shown in Figure 29-6.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 29-5 Insertion arc of the blade. Importantly, the thumb of the right hand, guides the blade during placement, as shown in Figure 29-6. he blade tip is then gently passed into the vagina between the fetal head and the palmar surface of the ingers of the right hand (Fig. 29-5). For application of the right blade, two or more ingers of the left hand are introduced into the right posterior portion of the vagina to serve as a guide for the right blade. his blade is held in the right hand and introduced into the vagina. With each blade, the thumb is positioned behind the heel, and most of the insertion force comes from this thumb (Fig. 29-6). If the head is positioned in a let OA (LOA) or right OA (ROA) position, then the lower of the two blades is typically placed irst. Mter positioning, the branches are articulated.


Obstentrics_Williams

Obstentrics_Williams. he blades are constructed so that their cephalic curve is closely adapted to the sides of the fetal head (Fig. 29-7). The fetal head is perfectly grasped only when the long axis of the blades corresponds to the occipitomental diameter (see Fig. 29-1). As a result, most of the blade lies over the lateral face. If the fetus is in an OA positi�n, then the concave arch of the blades is directed toward the sagittal suture. If the fetus is in an occiput posterior (OP) position, then the concave arch is directed toward the midline face.


Obstentrics_Williams

Obstentrics_Williams. Suboptimal blade placement can increase morbidity (Ramphul, 2015). For OA position, appropriately applied blades are equidistant from the sagittal suture, and each blade is equidistant from its adjacent lambdoidal suture. In the OP position, the blades are equidistant from the midline of the face and brow. Also for OP position, blades are symmetrically placed relative to the sagittal suture and each coronal suture. Applied in this way, the forceps should not slip, and traction may be applied most advantageously. With most forceps, if one blade is applied over the brow and the other over the occiput, the instrument cannot be locked, or if locked, the blades will slip of when traction is applied (Fig. 29-8). With both branches in place, it should be an easy matter to articulate the handles, engage the lock, and correct asynclitism if present. Asynclitism is resolved by pulling and/or pushing each branch along the long axis of the instrument until the


Obstentrics_Williams

Obstentrics_Williams. FIGURE 29-6 In applying the second blade, insertional force is generated mainly by the thumb. (Reproduced with permission from Yeomans ER: Operative vaginal delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201•7.) inger guards align. If necessary, rotation to OA position is performed before traction is applied (Fig. 29-9). When it is certain that the blades are placed satisfactorily, then gentle, intermittent, downward and outward traction is exerted concurrent with maternal eforts until the perineum FIGURE 29-7 A. The forceps are symmetrically placed and articulated. B.The vertex is OA. (Reproduced with permission from Yeomans ER: Operative vaginal delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201•7.)


Obstentrics_Williams

Obstentrics_Williams. FIGURE 29-8 Incorrect application of forceps. A. One blade over the occiput and the other over the brow. Forceps cannot be locked. B.With incorrect placement, blades tend to slip of with traction. begins to bulge. When the head is at 0 to + 2 of + 5 sta tion, the initial direction of traction is quite posterior, almost toward the Roor. With head descent, the vector of forces changes continuously (Fig. 29-10). As a teaching tool for this, a Bill axis traction device can be attached over the finger guards of most forceps. he instrument has an arrow and indicator line. When the arrow points directly to the line, traction is FIGURE 29-9 A. If LOA, the vertex is rotated (arrow) from this position to OA (B). (Reproduced with permission from Yeomans ER: Operative vaginal delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201o7.)


Obstentrics_Williams

Obstentrics_Williams. FIGURE 29-10 With low forceps, the direction of gentle traction for delivery of the head is indicated (arrow). The vector changes with fetal descent. along the path of least resistance. With traction, as the vulva is distended by the occiput, an episiotomy may be performed if indicated. Additional horizontal traction is applied, and the handles are then gradually elevated. As the handles are raised, the head is extended. During the birth of the head, mechanisms of spontaneous delivery should be simulated as closely as possible.


Obstentrics_Williams

Obstentrics_Williams. The force produced by the forceps on the fetal skull is a function of both traction and compression by the forceps, as well as friction produced by maternal tissues. It is impossible to ascertain the amount of force exerted by forceps for an individual patient. Traction should therefore be intermittent, and the head should be allowed to recede between contractions, as in spontaneous labor. Except when urgently indicated, as in severe fetal bradycardia, delivery should be suiciently slow, deliberate, and gentle to prevent undue head compression. It is preferable to apply traction only with each uterine contraction. Maternal pushing will augment these eforts.


Obstentrics_Williams

Obstentrics_Williams. After the vulva has been well distended by the head, the delivery may be completed in several ways. Some clinicians keep the forceps in place to control the head. If this is done, however, the blade volume adds to vulvar distention, thus from that in which they were originally placed. The fingers of the right hand, covered by a sterile towel, bolster the perineum. The thumb is placed directly on the head to prevent sudden egress. (Reproduced with permission from Yeomans ER: Operative vaginal delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201o7.) increasing the likelihood of laceration or necessitating a large episiotomy. To prevent this, the forceps may be removed, and delivery is then completed by maternal pushing (Fig. 29-11). Importantly, if blades are disarticulated and removed too early, the head may recede and lead to a prolonged delivery. Delivery in some cases may be


Obstentrics_Williams

Obstentrics_Williams. then completed by maternal pushing (Fig. 29-11). Importantly, if blades are disarticulated and removed too early, the head may recede and lead to a prolonged delivery. Delivery in some cases may be aided by addition of the modiied Ritgen maneuver.


Obstentrics_Williams

Obstentrics_Williams. Prompt delivery may at times become necessary when the small occipital fontanel is directed toward one of the sacroiliac synchondroses. In these right OP (ROP) or left OP (LOP) positions, the fetal head is often imperfectly lexed. With OP positions, second-stage labor can be lengthened. In these cases, the head may spontaneously deliver OP, may be manually or instrumentally rotated to an OA position, or may be delivered OP by forceps or vacuum. With manual rotation, an open hand is inserted into the vagina. The palm straddles the sagittal suture of the fetal head. The operator's ingers wrap around one side of the fetal face and thumb extends along the other side. If the occiput is ROP, rotation is clockwise to bring it to an ROA or OA position (Fig. 29-12).


Obstentrics_Williams

Obstentrics_Williams. /�(, _A.V\..IA...._ ./�...._/' B FIGURE 29-12 A. Manual rotation using the left hand, palm-up, to rotate from ROP. B. The head is flexed and destationed during clockwise rotation to reach an OA pOSition. (Reproduced with permission from Yeomans ER: Operative vaginal delivery. In Yeomans ER, Hofman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201o7.) FIGURE 29-14 Kielland forceps. The characteristic features are minimal pelvic curvature (A), sliding lock (8), and light weight.


Obstentrics_Williams

Obstentrics_Williams. FIGURE 29-14 Kielland forceps. The characteristic features are minimal pelvic curvature (A), sliding lock (8), and light weight. With LOr position, rotation is counterclockwise. hree actions are performed simultaneously between contractions. The irst is fetal head flexion to provide a smaller diameter for rotation and subsequent descent. Second, slight destationing of the fetal head moves the head to a level in the maternal pelvis with sufficient room to complete the rotation. Importantly, destationing should not be confused with disengaging the fetal head, which is proscribed. Concurrently, some prefer to also place the other hand externally on the corresponding side of the maternal abdomen to pull the fetal back up toward the midline in synchrony with the internal rotation. Le Ray and colleagues (2007, 2013) reported a success rate of greater than 90 percent with manual rotation. Barth (2015) provides an excellent summary of this technique.


Obstentrics_Williams

Obstentrics_Williams. Manual rotations are most easily completed in multiparas. If manual rotation cannot be easily accomplished, application of forceps blades to the head in the posterior position and delivery from an or position may be the safest procedure. In many cases, the cause of a persistent or position and of the diiculty in accomplishing rotation is an anthropoid pelvis. his architecture opposes rotation and predisposes to posterior delivery (Fig. 2-17, p. 31). With forceps delivery from an or position, downward and outward traction is applied until the base of the nose passes under the symphysis (Fig. 29-13). he handles are then slowly elevated until the occiput gradually emerges over the upper margin of the perineum. he forceps are directed downward again, and the nose, mouth, and chin successively emerge from the vulva.


Obstentrics_Williams

Obstentrics_Williams. or delivery causes greater distention of the vulva, and a large episiotomy may be needed. or deliveries have a higher incidence of severe perineal lacerations and extensive episiotomy compared with OA positions (de Leeuw, 2008; Pearl, 1993). Also, newborns delivered from or positions have a higher incidence ofErb and facial nerve palsies, 1 and 2 percent, respectively, than those delivered from OA positions. As expected, rotations to OA ultimately decrease perineal delivery trauma (Bradley, 2013). Last, for forceps rotations from an or to OA position, the Kielland instruments are preferred because they have a less pronounced pelvic curve (Fig. 29-14). Cunningham and Gilstrapis FIGURE 29-13 Outlet forceps delivery from an OP position. The head should be flexed ater the bregma passes under the symphysis. Operative Obstetrics, 3rd edition, ofers a more detailed description of this Kielland forceps procedure (Yeomans, 2017).


Obstentrics_Williams

Obstentrics_Williams. Operative Obstetrics, 3rd edition, ofers a more detailed description of this Kielland forceps procedure (Yeomans, 2017). With occiput transverse (OT) positions, rotation is required for delivery. With experienced operators, high success rates with minimal maternal morbidity can be achieved (Burke, 2012; Stock, 2013). Either standard forceps, such as Simpson, or specialized forceps, such as Kielland, are employed. With Kielland forceps, each handle has a small knob, and branches are placed so that this knob faces the occiput. he station of the fetal head must be accurately determined to be at, or preferably below, the level of the ischial spines, especially in the presence of extreme molding.


Obstentrics_Williams

Obstentrics_Williams. Kielland described two methods of applying the anterior blade. In our example, placement with a left OT (LOT) position is described. With the wandering method, the anterior blade is first introduced into the posterior pelvis (Fig. 29-15). The blade is then arched around the face to an anterior position. To permit this sweep of the blade, the handle is held close to the maternal left buttock throughout the maneuver. he second blade is introduced directly posteriorly, and the branches are locked.


Obstentrics_Williams

Obstentrics_Williams. After checking the application, the handles of the Kielland forceps are pulled slightly to the patient's right to increase fetal head lexion and create a smaller diameter for rotation. he irst and second fingers of the left hand are placed over the inger guards with the palm against the handles. his palm faces the maternal left. Concurrently, the first two ingers of the operator's right hand are placed against the anterior lambdoid suture. he fetal head is then destationed approximately 1 cm. For rotation in a counterclockwise direction, the wrist of the left hand supinates, to direct this palm upward. Simultaneously, two ingers of the right hand press on the edge of the right parietal bone that borders the lambdoid suture. This ensures that the fetal head turns with the blades and does not slip. he second type of blade application introduces the anterior blade with its cephalic curve directed upward to curve under


Obstentrics_Williams

Obstentrics_Williams. he second type of blade application introduces the anterior blade with its cephalic curve directed upward to curve under A B c FIGURE 29-15 A. Application of the right branch of the Kielland forceps to a head in LOT position. The knob on this branch (colored blue) will ultimately face the occiput. B. The right branch is wandered to its final position behind the symphysis. C. Insertion ofthe left branch of the Kielland forceps directly posterior along the hollow of the sacrum. This branch is inserted to the maternal right of the anterior branch to aid in engaging the sliding lock. (Reproduced with permission from Yeomans ER: Operative vaginal delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al (eds): Cunningham and Gilstrap's Operative Obstetrics, 3rd ed. New York, McGraw-Hili Education, 201•7.) the symphysis. After it has been advanced far enough toward the upper vagina, it is turned on its long axis through 180 degrees to adapt the cephalic curvature to the head.


Obstentrics_Williams

Obstentrics_Williams. With either application, after rotation completion, the operator may choose from two acceptable methods for delivery. In one, the operator applies traction on the Kielland forceps using a bimanual grip described previously for conventional forceps (p. 559). When the posterior fontanel has passed under the subpubic arch, the handles can be elevated to the horizontal. Raising the handles above the horizontal may cause vaginal sulcus tears because of the reverse pelvic curve (Dennen, 1955). Alternatively, the Kielland forceps can be removed after rotation and replaced with conventional forceps. With this approach, moderate traction is first employed to seat the head before switching instruments.


Obstentrics_Williams

Obstentrics_Williams. With a mentum anterior face presentation, forceps can be used to efect vaginal delivery. The blades are applied to the sides of the head along the occipitomental diameter, with the pelvic curve directed toward the neck. Downward traction is exerted until the chin appears under the symphysis. hen, by an upward movement, the face is slowly extracted, with the nose, eyes, brow, and occipur appearing in succession over the anterior margin of the perineum. Forceps should not be applied to the mentum posterior presentation because vaginal delivey is impossible except in vey smal ttuses.


Obstentrics_Williams

Obstentrics_Williams. With vacuum delivery, suction is created within a cup placed on the fetal scalp such that traction on the cup aids fetal expulsion. In the United States, vacuum extractor is the preferred term, whereas in Europe it is commonly called a vento use (Fig. 29-16). heoretical beneits of this tool compared with forceps include simpler requirements for precise positioning on the fetal head and avoidance of space-occupying blades within the vagina, thereby mitigating maternal trauma.


Obstentrics_Williams

Obstentrics_Williams. Vacuum devices contain a cup, shaft, handle, and vacuum generator. Vacuum cups may be metal or hard or soft plastic, and they may also difer in their shape, size, and reusability. In the United States, nonmetal cups are generally preferred, and there are two main types. he soft cup is a pliable bell-shaped dome, whereas the rigid type has a firm flattened mushroomshaped cup and circular ridge around the cup rim (Table 29-2). When compared, rigid mushroom cups generate significantly more traction force (Hofmeyr, 1990; Muise, 1993). With or positions or with asynclitism, the flatter cup also permits improved placement at the flexion point, which is typically less accessible with these head positions. The trade-of is that the flatter cups have higher scalp laceration rates. Thus, many manufacturers recommend soft bell cups for more straightforward OA deliveries.


Obstentrics_Williams

Obstentrics_Williams. Several investigators have compared outcomes with various rigid and soft cups. Metal cups provide higher success rates but greater rates of scalp injuries, including cephalohematomas -�..--A FIGURE 29-16 Vacuum delivery systems. A. The Kiwi OmniCup contains a handheld vacuum-generating pump, which is attached via flexible tubing to a rigid plastic mushroom cup. B. The Mityvac Mystic II MitySoft Bell Cup has a soft bell cup attached by a semirigid shaft to a handheld pump. TABLE 29-2. Vacuum Cups for Operative Vaginal Delivery "Reusable cups. bSuitable for occiput posterior positions or asynclitism. (For extractions through a hysterotomy incision during cesarean delivery.


Obstentrics_Williams

Obstentrics_Williams. (O'Mahony, 2010). In another study, Kuit and coworkers (1993) found that the only advantage of the soft cups was a lower incidence of scalp injury. hey reported a 14-percent episiotomy extension rate with both rigid and pliable cups. In a review, Vacca (2002) concluded that there were fewer scalp lacerations with the soft cup, but that the rate of cephalohematomas and subgaleal hemorrhage was similar between soft and rigid cups. Importantly, high-pressure vacuum generates large amounts of force regardless of the cup used (Duchon, 1998) . Aside from the cup, the shaft that connects the cup and handle may be lexible or semiflexible. Tubing-like flexible shafts may be preferred for OP positions or asynclitic presentation to permit better seating of the cup. Last, the vacuum generator may be handheld and actuated by the operator or may be held and operated by an assistant.