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CHAPTER 101: Emergency Delivery 637 Emergency Delivery Sarah Elisabeth Frasure Kathleen Kerrigan INTRODUCTION AND EPIDEMIOLOGY The thought of a woman presenting to the ED in active labor is justifi ably a cause for anxiety—the emergency physician must contend not only with the often rusty recollection of the stages of normal delivery but also with the knowledge that there are serious and even fatal complica tions associated with labor. Maternal and fetal survival may depend on the ability to successfully manage preeclampsia, eclampsia, hemorrhage, shoulder dystocia, malpresentation, cord prolapse, breech delivery, or fetal distress. Every ED should be prepared to take care of a woman in active labor. Tools include a basic delivery kit, an infant warmer or iso late, and medical supplies and equipment for neonatal resuscitation (see Chapter 108, “Resuscitation of Neonates” and Tables 101-1 and 101-2). Out-of-hospital births occurred in 1.36% of births in 2012. 1 Occasionally, planned home deliveries experience medical complications and require rapid transport to the ED to assist with labor and delivery. In a prospective study of home births in the United States and Canada, nearly 12% of 5400 women who had planned a home delivery ultimately required urgent transfer to a hospital during the course of labor. 2 The majority of intrapartum transfers were performed for failure to progress, need for pain management, and maternal exhaustion. Postpartum transfers encompassed a variety of complications such as maternal hemor rhage, retained placenta, or newborn respiratory distress. Out-of-hospital deliveries may also occur due to inadequate or non existent prenatal care, transportation difficulties, a remote setting, or the onset of premature labor. Occasionally, a woman may attempt to avoid the hospital/physician fees associated with pregnancy until the delivery of her child, presenting to a hospital for the first time when in active labor. The development of obstetric centers for high-risk pregnancy has led to a significant decline in neonatal mortality in the United States. The most common reasons for transport to such centers include preterm labor (41%), premature rupture of membranes (21%), hyper tensive disease (16%), and antepartum hemorrhage (13%). 3 Other indications for transport include eclampsia or preeclampsia, fetal distress, multiple gestation, fetal anomalies, and maternal health problems, including traumatic injuries. EMS units transporting an actively laboring patient should carry sterile delivery packs, relevant medical supplies (Table 101-1), and appropriate medications ( Table 101-2). The transport team should be trained to assist in the precipitous delivery of an infant. Prehospital protocols regarding the complica tions of labor and delivery should be reviewed regularly to ensure that EMS personnel are adequately prepared for both normal delivery and potentially catastrophic pregnancy-related events. For deliveries in an austere environment or in a disaster zone, the United Nations Population Fund provides a vaginal delivery kit for use during disaster relief, which includes a plastic sheet to lay on the ground, soap for washing hands and the perineum, string and a razor blade to tie and cut the umbilical cord, and a blanket to protect the newborn baby.

t or in a disaster zone, the United Nations Population Fund provides a vaginal delivery kit for use during disaster relief, which includes a plastic sheet to lay on the ground, soap for washing hands and the perineum, string and a razor blade to tie and cut the umbilical cord, and a blanket to protect the newborn baby.  LABOR PHYSIOLOGY  RUPTURE OF MEMBRANES Determining rupture of membranes predicts not only the likelihood of imminent labor but also the potential for complications, such as infection or cord prolapse. Spontaneous rupture of membranes occurs during the course of active labor in the majority of patients, although it also happens prior to onset of labor in approximately 8% of thirdtrimester patients. 5 Fifty percent of women who experience premature rupture of membranes deliver within 5 hours, and 95% give birth within 28 hours of this event. 6 The history of spontaneous rupture of mem branes typically involves report of a gush of clear or blood-tinged fluid. Occasionally, patients recount continued leaking or dampening of their underwear on standing or with a Valsalva maneuver. Greenish brown fluid suggests the presence of meconium in amniotic fluid. Rupture of membranes may be confirmed by using nitrazine paper to test residual fluid in the fornix or vaginal vault while performing a sterile speculum examination. Amniotic fluid has a pH of 7.0 to 7.4 and will turn nitrazine paper a dark blue. Vaginal fluid, on the other hand, typically has a pH of 4.5 to 5.5; the nitrazine strip, thus, remains yellow. False-positive results may occur, however, in the presence of blood, lubricant, Trichomonas vaginalis, semen, or even cervical mucus. Another test that confirms rupture of membranes is ferning, which is the observation of sodium chloride crystals on a microscope slide as amniotic fluid dries.  CERVICAL DILATATION Cervical dilatation describes the diameter of the internal cervical os and indicates the progression of labor. The index and middle fingers of the examining hand are used to estimate the diameter, which is expressed in centimeters (from closed to 10 cm). Dilatation of 10 cm indicates full dilatation. As labor progresses, the cervix also undergoes thinning, known as effacement, which is described in terms of a per centage of normal cervical length. Unfortunately, this estimate is poorly reproducible among examiners. Station indicates the level that the fetus occupies in the pelvis. The maternal ischial spines serve as the refer ence point and are palpable on either side of the vaginal canal (located at 4 and 8 o’ clock). If the presenting fetal part remains above the ischial spines, the station is described as negative. Once the presenting fetal part has reached the level of the ischial spines, the station is 0, with further descent into the pelvis described as +1 or +2. Therefore, a +3 station corresponds to visible scalp at the introitus, indicating a fetal position consistent with impending delivery.  TRUE VERSUS FALSE LABOR Distinguishing true from false labor is an important initial step in the management of the pregnant patient (Table 101-3). False labor is defined as uterine contractions that do not produce cervical changes and is characterized by irregular, brief contractions that are usually confined to the lower abdomen. Commonly known as Braxton Hicks contractions, they are irregular in both intensity and duration. False labor may persist for several days and is commonly treated with hydration and rest. True labor, on the other hand, is characterized by painful, repetitive uterine contractions that increase steadily in both intensity and duration and result in cervical effacement and dilatation.

ar in both intensity and duration. False labor may persist for several days and is commonly treated with hydration and rest. True labor, on the other hand, is characterized by painful, repetitive uterine contractions that increase steadily in both intensity and duration and result in cervical effacement and dilatation. Specifically, true labor pains typically commence in the fundal region and upper abdomen and radiate into the pelvis and lower back. True labor leads to not only CHAPTER TABLE 101-1 Equipment and Supplies for Emergency Delivery •   Sterile gloves •   Sterile towels and drapes •   Povidone-iodine or chlorhexidine to cleanse the perineum neither of these agents require trademark symbol •   Sterile lubricant gel •   Sterile scissors •   Kelly clamps •   Cord clamps •   Rubber suction bulb •   Towel or blanket for the infant •   Gauze sponges (4×4) •   Syringes (10 mL) and needles (22–24 gauge) •   Placenta basin •   Suture (3-0 chromic and 2-0 Vicryl) and needle driver Note: List excludes standard adult and neonatal resuscitation equipment. Tintinalli_Sec11_p0607-0668.indd 637 8/2/19 4:20 PM

uction bulb •   Towel or blanket for the infant •   Gauze sponges (4×4) •   Syringes (10 mL) and needles (22–24 gauge) •   Placenta basin •   Suture (3-0 chromic and 2-0 Vicryl) and needle driver Note: List excludes standard adult and neonatal resuscitation equipment. Tintinalli_Sec11_p0607-0668.indd 637 8/2/19 4:20 PM 638 SECTION 11: Obstetrics and Gynecology cervical dilatation and effacement but also the progressive descent of the fetus into the pelvis, in preparation for delivery.  STAGES OF LABOR There are three stages of labor (Table 101-4). The first stage commences with the onset of regular uterine contractions and ends with full cervi cal dilatation. The first stage can be subdivided into two phases: latent and active. The latent phase is characterized by moderately uncomfort able uterine contractions that are infrequent and irregular, resulting in gradual cervical changes. In this preparatory phase, the uterus orients to contractions and the cervix undergoes both effacement and softening. The active phase is typically noted to arise once the cervix has dilated to 3 to 4 cm and results in cervical dilatation at an average rate of 1.2 cm/h in nulliparous women and 1.5 cm/h in multiparous women. The second stage of labor commences at full dilatation and ends with the delivery of the infant. 7 The mean length of the second stage of labor is 20 minutes for multiparous women and 54 minutes for nulliparous women. 8 The third stage of labor starts after the delivery of the infant and ends with the delivery of the placenta. The third stage usually lasts less than 10 minutes, and active intervention is usually not required until after 30 minutes, unless hemorrhage occurs.  FETAL DISTRESS Fetal distress may occur during active labor. Indicators of fetal dis tress include fetal bradycardia or tachycardia, or late decelerations in fetal heart rate, which are defined as persistent drops in fetal heart rate both during and more than 30 seconds after a contraction. A physician or nurse trained in fetal monitoring can identify fetal dis tress (Figure 101-1). Doppler measurement of fetal heart tones is not reliable to detect decelerations. If decelerations are suspected, obtain emergency obstetrics consultation, and try to increase maternal blood flow by positioning the patient in the left lateral position, provide IV hydration, and administer oxygen. Further information is provided in the Advanced Life Support in Obstetrics course. CLINICAL EVALUATION When a patient >20 weeks’ gestation presents to the ED with signs of labor, immediately obtain both maternal vital signs (blood pressure, heart rate, respiratory rate, oxygen saturation, temperature) and the fetal heart rate.

information is provided in the Advanced Life Support in Obstetrics course. CLINICAL EVALUATION When a patient >20 weeks’ gestation presents to the ED with signs of labor, immediately obtain both maternal vital signs (blood pressure, heart rate, respiratory rate, oxygen saturation, temperature) and the fetal heart rate. Doppler US can be used to measure fetal heart rate; a normal fetal heart rate is generally 120 to 160 beats/min, bradycar dia is defined as less than 110 beats/min, and tachycardia is greater TABLE 101-2 Medications for Emergency Delivery and Indications for Use Classification Medication Dosage Indication/Use Contraindications Uterotonic Oxytocin 20 units/1000 mL normal saline or 10 units IM Stimulation of uterine contraction or as uterotonic for PPH Hypersensitivity Misoprostol 1000 micrograms PR, SL, or PO once Unlabeled use for PPH Hypersensitivity Methylergonovine 0.2 milligram IM or IV or PO; may repeat at 2- to 4-h intervals PPH Hypersensitivity, hypertension, eclampsia, preeclampsia Carboprost 250 micrograms IM every 15–90 min (total dose 2 milligrams) PPH Asthma Antihypertensive Hydralazine 5 milligrams IV, followed by 5- to 10-milligram boluses every 20 min Preeclampsia/eclampsia, hypertensive emergency Hypersensitivity Labetalol 20 milligrams IV, followed by doubled doses up to 80 milligrams (20–40–80–80) every 10 min; maximum total dose, 220 milligrams Preeclampsia/eclampsia, hypertensive emergency Hypersensitivity, sinus bradycardia Anticonvulsant Magnesium sulfate Loading dose of 4–6 grams IV over 15 min, followed by 2 grams/h infusion; can also give 5 grams IM in each buttock; max serum Mg = 8 mg/dL Seizure prophylaxis in preeclampsia/eclampsia Myasthenia gravis Electrolyte supplement toxicity Calcium gluconate 1 gram IV over 5 min Magnesium toxicity Hypersensitivity, cardiac arrhythmia Analgesic Lidocaine 1% 1–10 mL injected locally Local anesthetic Hypersensitivity Fentanyl, 50 micrograms/mL 50 micrograms/mL Short-acting opiate analgesic Hypersensitivity Opiate antagonist Naloxone 0.4–2.0 milligrams IV every 2–3 min as needed up to 10 milligrams cumulative dose Narcotic overdose Hypersensitivity Antiemetic Ondansetron 4 milligrams IV Nausea, vomiting Hypersensitivity Abbreviation: PPH = postpartum hemorrhage. TABLE 101-3 True Versus False Labor True Labor False Labor Contractions Rhythm Regular Irregular Intervals Gradually shorten Unchanged Intensity Gradually increases Unchanged Discomfort Location Back and abdomen Lower abdomen Sedation No effect Usually relieved Cervical dilatation Yes No Source: Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, Hauth JC, Rouse DJ, Spong CY (eds): Williams Obstetrics, 23rd ed. McGraw-Hill, Inc., 2010. Table 17-4 on AccessMedicine.com. TABLE 101-4 Stages of Labor Stage Definition Comments First stage From onset of regular uterine contractions to full cervical dilatation — Latent phase Irregular, infrequent contractions Preparatory phase, cervix softens and effaces Active phase Begins once cervix has dilated to 3–4 cm Nulliparas: cervix dilates at 1.2 cm/h Multiparas: cervix dilates at 1.5 cm/h Second stage From full dilatation to delivery Nulliparas: mean duration 54 min Multiparas: mean duration 20 min Third stage From delivery of infant to delivery of placenta 10 min; intervention not needed until >30 min Tintinalli_Sec11_p0607-0668.indd 638 8/2/19 4:20 PM

at 1.2 cm/h Multiparas: cervix dilates at 1.5 cm/h Second stage From full dilatation to delivery Nulliparas: mean duration 54 min Multiparas: mean duration 20 min Third stage From delivery of infant to delivery of placenta 10 min; intervention not needed until >30 min Tintinalli_Sec11_p0607-0668.indd 638 8/2/19 4:20 PM CHAPTER 101: Emergency Delivery 639 Uterine contraction monitoring Fetal heart tracing Uterine contraction monitoring Acceleration Flat fetal heart tracing Uterine contraction monitoring Variable decelerations Late decelerations FIGURE 101-1. Fetal heart rate variability and uterine contraction patterns. A. Good variability. B. Good variability with brief accelerations. Fetal heart rises above baseline and quickly returns to normal. A reassuring pattern. C. Poor variability. May be due to fetal hypoxia. D. Variable decelerations. No relationship to uterine contractions. May represent cord compression. E. Late deceleration. Occurs at onset of contraction and slow return to baseline after contraction ends. Signifies uteroplacental insufficiency and fetal hypoxia. [Reproduced with permission from Pearlman MD, Tintinalli JE, Dyne PL (eds): Obstetric and Gynecologic Emergencies: Diagnosis and Management. New York: McGraw-Hill, Inc.; 2003. Figs. 10-9 and 10-10, pp. 131 and 132.] Tintinalli_Sec11_p0607-0668.indd 639 8/2/19 4:20 PM

fies uteroplacental insufficiency and fetal hypoxia. [Reproduced with permission from Pearlman MD, Tintinalli JE, Dyne PL (eds): Obstetric and Gynecologic Emergencies: Diagnosis and Management. New York: McGraw-Hill, Inc.; 2003. Figs. 10-9 and 10-10, pp. 131 and 132.] Tintinalli_Sec11_p0607-0668.indd 639 8/2/19 4:20 PM 640 SECTION 11: Obstetrics and Gynecology than 160 beats/min. 9 A persistently slow fetal heart rate indicates fetal distress and requires emergency obstetric consultation. As part of the initial evaluation, obtain IV access, procure baseline laboratory studies including blood type, and send a urinalysis.  HISTORY Ask about the onset and frequency of uterine contractions, fetal mem brane status, presence or absence of vaginal bleeding, and presence or absence of fetal movement. The obstetric history should include parity, history of complications with prior deliveries, history of precipitous deliveries, prenatal care during this pregnancy, and estimated date of delivery. Obtain a medical and surgical history and a list of current medications and allergies, and ask the patient about substance abuse. Inquire about symptoms of infection, such as fevers, chills, or foulsmelling vaginal discharge. Gestational Age If the patient knows the first day of her last men strual period, the estimated date of delivery can be calculated by adding 9 months and 7 days to that date (Nägele’s rule). Fundal height also provides a rapid estimate of gestational age once greater than 20 weeks and is measured in centimeters (cm) from the pubic symphysis to the top of the fundus (cm = weeks of gestation ±2 weeks). Fundal height may be falsely overestimated in the obese patient and underestimated in active labor when the fetal head has descended into the pelvis. Bedside US also provides a useful assessment of gestational age in the third trimester, but estimated age can vary by ±3 weeks.  PHYSICAL EXAMINATION Monitor vital signs for evidence of maternal fever, tachycardia, or elevated blood pressure. Assess fetal heart tones for bradycardia or tachycardia. Do not keep the pregnant woman flat on her back for a prolonged time period. Compression of venous return by the gravid uterus can lead to hypotension in the mother, which in turn results in decreased blood supply to the fetus. Place the patient in the left lateral position following the physical examination . On abdominal examination, determine fundal height, abdominal or uterine tenderness to palpation, and presence of uterine contractions. Examine the perineum for perineal lesions, such as those caused by herpes simplex virus, which may be a contraindication for a vaginal delivery.  PELVIC EXAMINATION Vaginal Bleeding Present Patients with vaginal bleeding should be evaluated with bedside US prior to speculum or bimanual examina tion in order to rule out placenta previa. No Vaginal Bleeding Patients without vaginal bleeding should be evaluated first with a sterile speculum examination to determine if membranes have been ruptured, to note cervical dilatation, and to determine fetal station and presentation. Bedside US is the simplest method to verify presentation. Vertex presentation and lie can also be confirmed through palpation of the cranial sutures on digital examination. Palpa tion of small parts, such as feet or hands, often indicates malpresentation and will require urgent obstetrics consultation. If meconium is present on the examining finger, be prepared for neonatal resuscitation (see Chapter 108, “Resuscitation of Neonates”).

lpation of the cranial sutures on digital examination. Palpa tion of small parts, such as feet or hands, often indicates malpresentation and will require urgent obstetrics consultation. If meconium is present on the examining finger, be prepared for neonatal resuscitation (see Chapter 108, “Resuscitation of Neonates”). Rupture of Membranes If rupture of membranes is suspected , perform a sterile speculum examination (do not use lubricant because lubricant may produce a false-positive nitrazine test), but do not per form a digital examination because even one digital examination increases the risk of infection. 10 Also avoid digital examinations in the preterm patient in whom the prolongation of gestation is desired.  EMERGENCY DELIVERY If time allows, prepare the perineum by washing it with mild soap and water and swabbing with povidone-iodine. Place drapes over the patient. Medical personnel attending to the patient should don gowns, masks, and gloves. The first steps in the management of a woman in active labor are to measure vital signs and initiate supportive therapy. Obtain venous access, provide IV hydration, and initiate maternal and fetal monitor ing (if available). Delivery is imminent if the pelvic examination reveals complete cervical effacement and the fetus is at the introitus. Labor can progress very rapidly, particularly in multiparous patients. Both the stage of labor and the parity of the patient should be taken into account when considering whether to transport a laboring patient to the labor and delivery suite or to another facility. If the cervix is fully effaced and dilated or the fetal head is visible during contractions, the obstetri cian (if available) should come to the ED rather than risk a precipi tous delivery during transport to the delivery suite. As the cervix fully dilates, effacement becomes complete, the fetus descends into the pelvis, and the patient will experience the urge to push. The cervix should be fully dilated before the patient begins to push in order to avoid cervical lacerations. If not already done by US, determine fetal presentation by palpating skull sutures and fontanelle or the buttock or extremity. Six cardinal movements describe the process of fetal descent during labor and delivery: (1) engagement, (2) flexion, (3) descent, (4) internal rotation, (5) extension, and (6) external rotation (Figure 101-2). The following discussion describes delivery in the cephalic, occiput anterior position. As the fetus descends through the birth canal and reaches the introitus, the perineum bulges in order to accommodate the fetal head. Gentle digital stretching of the inferior portion of the perineum can aid delivery. The perineum undergoes gradual thinning and stretching to enable passage of the newborn. (See Video: Vaginal Delivery With Episiotomy.)  EPISIOTOMY Routine episiotomy for a normal spontaneous vaginal delivery varies with practitioner, institution, and country. Episiotomy may be necessary to expedite a delivery in cases of fetal distress or shoulder dystocia or if forceps or vacuum devices are used (Figure 101-3).11 The episiotomy can be performed in the midline or mediolaterally (45 degrees from the midline). Median episiotomy is easy to perform and has less maternal discomfort during recovery, but mediolateral episiotomy has a lower risk of extension to the anal sphincter (third-degree extension) or to the rectum (fourthdegree extension) than median episiotomy. If an episiotomy is clinically necessary, first inject 5 to 10 mL of 1% lidocaine solution with a smallgauge needle into the posterior fourchette and perineum. While protecting the infant’s head, make a 2- to 3-cm incision with scissors in order to extend the vaginal opening, either at the midline or 45 degrees from the midline.

iotomy is clinically necessary, first inject 5 to 10 mL of 1% lidocaine solution with a smallgauge needle into the posterior fourchette and perineum. While protecting the infant’s head, make a 2- to 3-cm incision with scissors in order to extend the vaginal opening, either at the midline or 45 degrees from the midline. A median incision must be supported with manual pressure from below. Take care to prevent extension of the incision into the rectum.  COMPLETION OF DELIVERY Do not drop the baby. The combination of amniotic fluid, blood, and vernix generates a very slippery infant. Before delivering the rest of the body, place your posterior hand underneath the axilla of the infant. Use the anterior hand to grasp the ankles of the infant with a firm grip. Fol lowing delivery, keep the infant warm and provide gentle stimulation. Do not routinely suction the nose and mouth. Suctioning can cause fetal bradycardia and hypoxia. See Chapter 108, “Resuscitation of Neonates, ” for further discussion of neonatal respiratory distress. If delivery is uncomplicated, and the infant has responded well to initial stimulation with a clear airway and good respiratory effort, the mother may hold the child immediately while the cord is cut. Apgar scores are calculated at 1 and 5 minutes after delivery. Scoring parameters include general color, tone, heart rate, respiratory effort, and reflexes (Table 101-5). For an APGAR score of <7, refer to Chapter 108, “Resuscitation of Neonates. ” Provide positive-pressure ventilation for all newborns with a heart rate <100 beats/min or who are gasping or apneic after 30 seconds. CLAMPING THE UMBILICAL CORD Do not clamp the umbilical cord of term or preterm infants for at least 1 to 3 minutes after birth. Delayed cord clamping increases neo natal iron stores. Double-clamp the umbilical cord 3 cm distal to its Tintinalli_Sec11_p0607-0668.indd 640 8/2/19 4:20 PM

asping or apneic after 30 seconds. CLAMPING THE UMBILICAL CORD Do not clamp the umbilical cord of term or preterm infants for at least 1 to 3 minutes after birth. Delayed cord clamping increases neo natal iron stores. Double-clamp the umbilical cord 3 cm distal to its Tintinalli_Sec11_p0607-0668.indd 640 8/2/19 4:20 PM CHAPTER 101: Emergency Delivery 641 insertion at the umbilicus and transect with sterile scissors. In delivery settings where aseptic care is routine, there is no clear benefit to any additional topical care of the umbilicus. When aseptic care is not available, however, antiseptic topical care of the umbilicus with chlorhexidine reduces the risk of omphalitis and neonatal mortality. 12 Once the umbilical cord is cut, dry the infant and either give the infant to the mother or place it in a warming unit. DELIVERY OF THE PLACENTA The placenta usually delivers 10 to 30 minutes after delivery of the infant. Allow the placenta to separate spontaneously and provide only gentle traction. Aggressive traction on the cord can lead to uterine inversion, tearing of the cord, or disruption of the placenta, all of which can result in severe vaginal bleeding. After the placenta has been removed, A Occiput anteriorB C D FIGURE 101-2. The movements of normal delivery for a vertex presentation. A. Engagement, flexion, and descent with vertex anterior. B. Internal rotation with occiput becoming anterior. C. Extension and delivery of the head. As the infant’s head emerges from the introitus, support the perineum by placing a sterile towel along the inferior part of the perineum with one hand, and support the fetal head with the other hand. Ask the mother to breathe through contractions (rather than bear down) in order to deter rapid expulsion of the baby. Provide mild counterpressure for controlled extension of the fetal head. As the infant’s head presents, use the inferior hand to control the fetal chin and keep the superior hand on the crown of the head, supporting the delivery. D. External rotation, bringing the thorax into the anteroposterior diameter of the pelvis. As the head delivers, palpate the infant’s neck to assess for the presence of a nuchal cord. Nuchal cord is noted in approximately 25% to 35% of all term deliveries. 8 If the cord is loose, move it over the infant’s head, and allow delivery to proceed as usual. If the cord is wound tightly around the neck, however, apply two close clamps in the most accessible area, and then cut the cord. E. Delivery of the anterior shoulder. Once the head is delivered, it will turn to one side or the other. Grasp the sides of the head with both hands and apply gentle downward traction (go with gravity) until the anterior shoulder is delivered. Jerky or aggressive traction may injure the brachial plexus. If you have not checked for a nuchal cord, do so now. As the head rotates, place the hands on either side of the head, providing gentle downward traction. This maneuver allows for the delivery of the anterior shoulder. F. Delivery of the posterior shoulder. Use an upward movement to deliver the upward shoulder. Do not apply traction. If meconium is present or the newborn is limp or poorly responsive, stimulate the baby and be prepared to begin the steps of neonatal resuscitation with ventilation and oxygenation (see Chapter 108, “Resuscitation of Neonates”). Tintinalli_Sec11_p0607-0668.indd 641 8/2/19 4:20 PM

upward shoulder. Do not apply traction. If meconium is present or the newborn is limp or poorly responsive, stimulate the baby and be prepared to begin the steps of neonatal resuscitation with ventilation and oxygenation (see Chapter 108, “Resuscitation of Neonates”). Tintinalli_Sec11_p0607-0668.indd 641 8/2/19 4:20 PM 642 SECTION 11: Obstetrics and Gynecology gently massage the abdomen at the level of the fundus to promote con traction. Give oxytocin (10 to 40 units in 1 L normal saline at 250 mL/h or 10 units IM) to sustain uterine contraction. The estimated blood loss during a vaginal delivery is usually less than 500 mL. Uterine atony, however, which occasionally follows a precipitous delivery, can lead to excessive vaginal bleeding. In that case, give addi tional oxytocin or another uterotonic of choice ( Table 101-2). As con tractile agents are administered, provide vigorous bimanual massage. If concerned about an episiotomy complication, delay episiotomy or laceration repair until an experienced obstetrician is available to close the laceration and inspect for fourth-degree perineal lacerations. COMPLICATIONS OF LABOR AND DELIVERY  UMBILICAL CORD PROLAPSE Umbilical cord compression is life threatening to the fetus. Obtain immediate obstetric assistance, as emergent cesarean delivery is indi cated. Should the speculum or bimanual examination reveal a palpable, pulsating umbilical cord, elevate the presenting fetal part to reduce compression on the cord. Keep your hand in the vagina while the patient is transported and prepared for surgery to prevent further compression of the cord by the fetal head. Place the mother in the Trendelenburg position. Do not try to reduce the prolapsed cord.  SHOULDER DYSTOCIA Shoulder dystocia is the impaction of fetal shoulders at the pelvic outlet after delivery of the head. Typically, the anterior shoulder is trapped behind the pubic symphysis and prevents delivery of the rest of the infant. 15,16 Complications of shoulder dystocia include fetal bra chial plexus injury (due to overaggressive traction), clavicle fracture, fetal hypoxia (due to impaired respirations and/or compression of the umbilical cord), postpartum hemorrhage, and fourth-degree perineal lacerations. Prior to delivery of the head, the head may retract between contrac tions. Shoulder dystocia then becomes evident when routine downward traction fails to deliver the anterior shoulder once the head has been delivered. After the infant’s head is delivered, the head retracts tightly against the perineum (turtle sign; Figure 101-4). 17 Several steps can be used to relieve shoulder dystocia (Table 101-6). Immediately place the mother in the extreme lithotomy position, with her legs sharply flexed up to the abdomen and the knees held as widely apart as possible (McRoberts maneuver; Figure 101-5). Either the mother or an assistant should keep the legs held widely apart. Simultaneously apply supra pubic pressure. If a second assistant is available, he or she should place their hands in a CPR position and apply downward pressure just above the pubic symphysis for 1 to 2 minutes to disimpact the anterior shoulder. Do not apply pressure to the uterine fundus, as this maneuver can further impact the shoulder. Suprapubic pressure serves TABLE 101-6 Steps to Relieve Shoulder Dystocia Steps Comments Flex thighs and keep knees apart as much as possible McRoberts maneuver Apply suprapubic pressure Keep patient in McRoberts position. Place one hand with wrist clenched, immediately above the pubic symphysis, and push the anterior fetal shoulder to dislodge it. If an assistant is available, place two clenched wrists in CPR position just above pubic symphysis, again using pressure to dislodge the anterior shoulder. Compress for 1 min. Do not compress uterine fundus.

with wrist clenched, immediately above the pubic symphysis, and push the anterior fetal shoulder to dislodge it. If an assistant is available, place two clenched wrists in CPR position just above pubic symphysis, again using pressure to dislodge the anterior shoulder. Compress for 1 min. Do not compress uterine fundus. This worsens impaction. Deliver posterior arm Insert hand into posterior vagina, identify arm, and sweep across chest. Rotational maneuvers Typically require episiotomy. Attempt to place shoulders in a different diameter. See text. TABLE 101-5 Apgar Scoring for Newborns Sign 0 Points 1 Point 2 Points A Activity (muscle tone) Absent Arms and legs flexed Active movement P Pulse Absent Below 100 beats/ min Above 100 beats/min G Grimace (reflex irritability) No response Grimace Sneezing, coughing, pulling away A Appearance (skin color) Blue-gray, pale Normal, except extremities Normal over entire body R Respiration Absent Slow, irregular Good, crying Anus Midline episiotomy Mediolateral episiotomy Vaginal opening Fetal head bulging Operating scissors FIGURE 101-3. Methods for episiotomy. FIGURE 101-4. Clinical appearance of shoulder dystocia. The infant’s head is impacted against the perineum. [Reprinted with permission from Buckley RG, Knoop KJ: Gynecologic and obstetric conditions, in Knoop KJ, Stack LB, Storrow AB (eds): Atlas of Emergency Medicine, 2nd ed. New York: McGraw-Hill, Inc.; 2002, Figure 10.46.] Tintinalli_Sec11_p0607-0668.indd 642 8/2/19 4:21 PM

infant’s head is impacted against the perineum. [Reprinted with permission from Buckley RG, Knoop KJ: Gynecologic and obstetric conditions, in Knoop KJ, Stack LB, Storrow AB (eds): Atlas of Emergency Medicine, 2nd ed. New York: McGraw-Hill, Inc.; 2002, Figure 10.46.] Tintinalli_Sec11_p0607-0668.indd 642 8/2/19 4:21 PM CHAPTER 101: Emergency Delivery 643 FIGURE 101-5. McRoberts maneuver. Sharply flex the thighs up onto the abdomen, as shown by the horizontal arrow, and keep the knees spread widely. Simultaneously provide suprapubic pressure (vertical arrow). [Adapted with permission from Cunningham FG, Leveno KL, Bloom SL, et al: Williams Obstetrics, 22nd ed. New York: McGraw-Hill, Inc.; 2005, Figure 20-14.] FIGURE 101-6. Woods corkscrew maneuver, rotating the posterior shoulder. to rotate the shoulder under the pubic symphysis.17 The combination of the McRoberts position and suprapubic pressure relieves about 50% of shoulder dystocias. In the event that the above maneuvers are unsuccessful, the delivery of the posterior arm can be considered as the next maneuver to manage shoulder dystocia.17 To perform this maneuver, the provider reaches into the vagina and identifies the posterior arm. The elbow is flexed and the arm is swept across the fetal chest. This will usually allow the arm to deliver and the anterior shoulder will be disimpacted, allowing the rest of the fetus to deliver. Should this procedure fail, rotational maneuvers should be attempted. The Rubin maneuver is accomplished by placing a hand on the back surface of the posterior shoulder and rotating the fetus toward the fetal face. The Woods’ corkscrew maneuver (Figure 101-6) is accomplished by placing a hand on the anterior surface of the posterior shoulder and rotating toward the fetal back. Sling procedures have also been described where a finger or 12F or 14F suction catheter is placed through the axilla of the posterior arm. Moderate traction is applied to deliver the posterior shoulder. Do not rotate the head. All of the above maneuvers require an episiotomy to allow the provider to place a hand in the vagina. The Gaskin maneuver ( Figure 101-7) can also be employed. It is a simple maneuver, but with IVs and monitors in place or with an exhausted mother, it can be difficult to achieve. Place the patient on all fours. Exert gentle downward traction on the infant’s head. To remember the direction of traction, remember to “go with gravity. ” In 80% of cases, this maneuver allows the posterior shoulder to successfully deliver. Tintinalli_Sec11_p0607-0668.indd 643 8/2/19 4:21 PM

n be difficult to achieve. Place the patient on all fours. Exert gentle downward traction on the infant’s head. To remember the direction of traction, remember to “go with gravity. ” In 80% of cases, this maneuver allows the posterior shoulder to successfully deliver. Tintinalli_Sec11_p0607-0668.indd 643 8/2/19 4:21 PM 644 SECTION 11: Obstetrics and Gynecology FIGURE 101-7. Gaskin maneuver. Move the mother onto all fours. This maneuver can widen the pelvic outlet.  BREECH PRESENTATION Breech presentations occur in 3% to 4% of term pregnancies. Risks of breech presentations include umbilical cord prolapse, trauma, hypoxia, and fetal distress. Breech presentations occur most frequently in the delivery of premature infants; approximately 25% to 30% of all preterm infants (<28 weeks’ gestation) present in breech position. 18 Given the increased perinatal/neonatal morbidity and mortality associated with vaginal breech deliveries, cesarean section is recommended in breech presentations. Head entrapment is a major concern in a breech delivery. In a nor mal cephalic delivery, the larger head dilates the cervical canal, which ensures that the rest of the infant’s body can follow. In a breech delivery, however, the head emerges last and may become stuck in an incom pletely dilated cervix. In frank and complete breech deliveries, the buttocks dilate the cervix almost as well as the fetal head; therefore, emergency delivery may be able to proceed in an uncomplicated fashion. First, determine breech position and full cervical dilation. Check for prolapsed cord. Footling and incomplete breech positions are not safe for vaginal delivery due to the risk of cord prolapse or incomplete dilatation of the cervix. Immediately obtain emergency obstetric consultation for any breech presentation. Allow the delivery to proceed spontaneously to the level of the umbilicus and do not apply traction ( Figure 101-8). The legs will typically deliver spontaneously at this time, or one can insert a finger behind the knee to flex and abduct the baby’s thigh to deliver the legs. Once the umbilicus is evident, gently place your thumbs on the sacrum and gently grasp the fetal pelvis with your hands. Keep the trunk at no more than 45 degrees to the horizontal. Y ou may need to kneel on the floor. Maintain or redirect the baby’s sacrum anterior. Allow each arm to deliver with slight fetal oblique rotation for each arm, and then main tain sacrum anterior position. Y ou can have an assistant place the baby’s torso in a towel fashioned like a sling for better support. To safely deliver the head, maintain cervical flexion by placing one hand on the fetal occiput and shoulders, and apply flexing pressure on the occiput; and place the fingers of the other hand on the infant’s maxillae to aid in cervical flexion. An assistant can apply suprapubic pressure to the mother to maintain cervical flexion. Maintain cervical flexion, and the baby’s body will then deliver in a large arc, with the sling providing support.  POSTPARTUM HEMORRHAGE Postpartum hemorrhage usually occurs within the first 24 hours of delivery and is referred to as primary postpartum hemorrhage . The main causes of primary postpartum hemorrhage include uterine atony, retained placental fragments, lower genital tract lacerations, uterine rupture, uterine inversion, and hereditary coagulopathy. Table 101-7 lists the most common risk factors. Secondary postpartum hemor rhage occurs after the first 24 hours and up to 6 weeks postpartum. Common causes of secondary postpartum hemorrhage are failure of the uterine lining to subinvolute at the former placental site, retained placental tissue, genital tract wounds, and uterogenital infection.

common risk factors. Secondary postpartum hemor rhage occurs after the first 24 hours and up to 6 weeks postpartum. Common causes of secondary postpartum hemorrhage are failure of the uterine lining to subinvolute at the former placental site, retained placental tissue, genital tract wounds, and uterogenital infection. 19,20 Excessive blood loss in the postpartum period is defined as a 10% drop in the hematocrit, a need for transfusion of packed red blood cells, or volume loss that generates symptoms of hypovolemia. Normally, plasma volume increases by 40% and red blood cell volume by 25% by the end of the third trimester. The hematologic changes of pregnancy can mask the typical symptoms of hemorrhage; the first sign may be only a mild increase in pulse rate. Up to a 30% loss in total blood volume may occur before the blood pressure drops. Most cases of postpartum hemorrhage are the results of uterine atony. Another 20% result from cervical, vaginal, or perineal lacera tions. Retention of placental tissue may account for 10%, and underlying coagulopathy is an uncommon cause. 20 The initial resuscitative steps include aggressive fluid and blood resuscitation while identifying and treating the underlying cause (Tables 101-2 and 101-8). Non pneumatic antishock garments can be applied in combination with fluid resuscitation and uterotonics, resulting in reduced blood loss and increased maternal survival in remote settings or with delayed transport. Uterine atony is the most common cause of postpartum hemor rhage. Risk factors include preeclampsia, protracted use of uterotonics or tocolytics, prolonged labor, multifetal gestation, fetal macrosomia, multiparity, retained placenta, and uterine infection. Initiate bimanual uterine massage; place a fist in the anterior fornix and compress the uterine fundus against the hand in a suprapubic location (Figure 101-9). Retention of placental fragments or abnormal placental implantation (placenta accreta) may cause severe hemorrhage and may require emergency pelvic embolectomy, hemostatic brace sutures (B-Lynch sutures), or peripartum hysterectomy.  UTERINE INVERSION AND RUPTURE Uterine inversion generally results from excessive force or overzealous attempts to remove the placenta in order to manage the third stage of labor. 22 Inversion can also occur in patients with connective tissue disorders and uterine structural anomalies. It can be difficult to detect uterine inversion, particularly if the fundus remains cephalad to the cervix. The diagnosis can be made, however, with transvaginal or transabdominal US. Uterine inversion requires immediate manual replacement of the uterus. A Rüsch balloon catheter can be applied to correct uterine inversion. As with any device, be gentle when inserting anything into an immediate postpartum uterus. The tissue is very soft, and uterine perforation is a very real risk. 22 Of note, the correction of uterine inversion is a very painful and difficult procedure that may require general anesthesia and tocolytic agents. Though rare, uterine rupture carries a high risk of maternal and fetal mortality. Previous cesarean section is the primary risk factor for uterine rupture, and single-layer surgical closure of the uterus, fetal size >3500 grams, and labor augmentation increase the rate of rupture dur ing a trial of labor. Anatomic abnormalities such as a bicornuate uterus, grand multiparity, history of connective tissue disorders, and abnormal placentation are also associated with rupture. Clinical signs of uterine rupture are persistent abdominal pain, severe vaginal bleeding, loss of fetal station, and palpable uterine defect. Fetal monitors may show fetal Tintinalli_Sec11_p0607-0668.indd 644 8/2/19 4:21 PM

tory of connective tissue disorders, and abnormal placentation are also associated with rupture. Clinical signs of uterine rupture are persistent abdominal pain, severe vaginal bleeding, loss of fetal station, and palpable uterine defect. Fetal monitors may show fetal Tintinalli_Sec11_p0607-0668.indd 644 8/2/19 4:21 PM CHAPTER 101: Emergency Delivery 645 FIGURE 101-8. A. Breech usually presents with the sacrum oblique, but most often spontaneously turns to sacrum anterior. B. Always allow spontaneous delivery to the umbilicus. If the sacrum has not rotated to the anterior position, put your thumbs on the sacrum and hands underneath on the pelvis (not abdomen) and gently rotate the sacrum anterior. C. Freeing the legs. The legs will typically deliver spontaneously. If not, grasp one leg at the popliteal fossa and sweep the leg out. Do the same with the other leg. Inset shows how to sweep the leg out laterally. D. Freeing the shoulders. Once the scapulae are evident, to turn the shoulders, grasp the sacrum and pelvis as described in B, and rotate clockwise and counterclockwise to free both shoulders. Then maintain the sacrum in an anterior position. E. To safely deliver the head, maintain cervical flexion by placing one hand on the fetal occiput and shoulders, apply flexing pressure on the occiput, and place the fingers of the other hand on the infant’s maxillae (inset) to aid in cervical flexion. An assistant can apply suprapubic pressure to the mother to maintain cervical flexion. F. The delivery is completed by sweeping the baby through an arc; the infant’s body flips over and can be placed in the mother’s arms. Tintinalli_Sec11_p0607-0668.indd 645 8/2/19 4:21 PM

s maxillae (inset) to aid in cervical flexion. An assistant can apply suprapubic pressure to the mother to maintain cervical flexion. F. The delivery is completed by sweeping the baby through an arc; the infant’s body flips over and can be placed in the mother’s arms. Tintinalli_Sec11_p0607-0668.indd 645 8/2/19 4:21 PM 646 SECTION 11: Obstetrics and Gynecology FIGURE 101-9. Treatment of uterine atony. Perform bimanual uterine massage, place a fist in the anterior fornix, and compress the uterine fundus against the hand. [Reproduced with  permission  from  Cunningham  G,  Leveno  KL,  Bloom  SL,  Hauth  JC,  Rouse  DJ,  Spong  CY (eds): Williams Obstetrics, 23rd ed. © 2010. The McGraw-Hill Companies, Inc. New York, Figure 35–17.] TABLE 101-7 Risk Factors for Postpartum Hemorrhage •   Primiparity or grand multiparity •   Previous postpartum hemorrhage •   Preeclampsia •   Prior cesarean section •   Placenta previa or low-lying placenta •   Marginal umbilical cord insertion •   Transverse fetal lie •   Labor induction or augmentation •   Cervical or uterine trauma •   Fetal age <32 weeks of gestation •   Fetal birth weight >4500 grams •   Prolonged third stage of labor TABLE 101-8 Common Causes and Treatment of Postpartum Hemorrhage Cause Treatment Tone Perform bimanual uterine massage. Give drugs to improve uterine tone as outlined in Table 101-2. Trauma Examine for cervical, vaginal, or perineal lacerations or hematomas. Repair lacerations. Incise, drain, and appropriately ligate bleeding vessels causing a hematoma. Correct uterine inversion with manual replacement. Uterine rupture requires surgery. Tissue Inspect the placenta for missing fragments; if a portion is absent, manually evacuate the uterine cavity. Invasive placentation may require hysterectomy. Perform transvaginal or transabdominal US to identify abnormal fluid-filled uterus. Consider a balloon tamponade with either uterine-specific balloon device (Bakri or Rüsch) or an adaptation of a Foley catheter or condom as a temporizing measure. Thrombin Consider DIC in the setting of severe preeclampsia, sepsis, placental abruption, shock, or intrauterine fetal demise, although undiagnosed coagulopathies may rarely present in nulliparas. Replace coagulation factors. Abbreviation: DIC = disseminated intravascular coagulation. distress and bradycardia. The diagnosis of uterine rupture must be made clinically and rapidly. Treatment is aggressive fluid and blood resuscitation and surgical delivery of the fetus.  AMNIOTIC FLUID EMBOLUS Amniotic fluid embolus is a rare and often catastrophic complication of pregnancy that occurs when amniotic fluid and cells of fetal origin enter the maternal circulation during labor or delivery. Most cases occur before delivery. Fetal and maternal mortality rates are high. Amniotic fluid embolism is very difficult to diagnose. The onset of symptoms until cardiovascular collapse can range from seconds to >4 hours. Presenting signs include respiratory distress, hypoxia, pulmonary edema, altered mental status, seizures, sudden maternal cardiovascular collapse, dis seminated intravascular coagulation, and sudden onset of fetal distress. Postulated causes are antigenic stimuli or activation of the clotting cascade when amniotic fluid enters the maternal circulation. Physiologically, the hemodynamic changes identified on echocardiogram are the result of acute onset of severe pulmonary hypertension, right ventricular failure with leftward deviation of the septum, and the absence of pul monary edema. Secondarily, left ventricular filling becomes impaired due to profound right heart failure, eventually resulting in myocardial ischemia. Death can occur rapidly. Treatment is supportive, and there are no specific interventions currently available.

h leftward deviation of the septum, and the absence of pul monary edema. Secondarily, left ventricular filling becomes impaired due to profound right heart failure, eventually resulting in myocardial ischemia. Death can occur rapidly. Treatment is supportive, and there are no specific interventions currently available. The physician should prevent and/or treat hypoxia, hypotension, and hypoperfusion. Place the woman in the left lateral decubitus position to minimize vena cava compression; give oxygen by nonrebreather mask or endotracheal tube, resuscitate with fluid and blood, and administer pressors to support maternofetal circulation until emergency delivery of the fetus is performed. Obtain emergency obstetric consultation. If the gravid patient cannot be resus citated, perimortem cesarean delivery within 5 minutes of cardiac arrest increases the chances of neonatal survival.  EMERGENCY CESAREAN SECTION Perimortem cesarean section or resuscitative hysterotomy is a proce dure rarely performed by emergency providers. The decision to deliver a woman while CPR is in progress is daunting. The American Heart Association 2015 guidelines advise that the decision to perform the procedure should be made after 4 minutes of CPR and the delivery should be accomplished by 5 minutes. 24 These guidelines are commonly known as the 4-Minute Rule and the 5-Minute Rule. This is very difficult to accomplish. Even in the scenario of simulation on an obstetric unit with obstetric providers, timing is problematic. 25 Any woman receiving CPR who is ≥20 weeks’ pregnant may benefit from delivery, and it is wise to prepare beforehand if possible. To estimate gestational age, keep in mind the uterus will be at the umbilicus at about 20 weeks. Manually displace the uterus to the left to minimize compression of the inferior vena cava. Ideally there should be an emergency delivery kit in the department. If not, the procedure can be performed with minimal equipment. Required items include skin antiseptic, a scalpel, scissors, suction, Kelly clamps or umbilical cord clamps, and retractors if available. Time to delivery is critical, so do not move the patient to another location. 24 Apply the antiseptic solution to the abdomen. Place a drape if available. Make a vertical incision with the scalpel, starting at the xiphoid process and extending to the pubic symphysis. The lengthy incision will allow adequate exposure. The incision should go through the skin, fat, fascia, and peritoneum. Be careful to identify the blad der and retract it. 26 Then carefully incise the uterus with the scalpel, with an incision large enough to accommodate two fingers. In order to protect the fetus from injury, insert two fingers through the initial incision and elevate the uterine wall off the fetus. Use the scissors to divide the uterus between the fingers, and extend the incision in a vertical fashion. Then deliver the fetus ( Figures 101-10 to 101-12). The mouth and nose should be suctioned if possible. Doubly clamp and cut the cord. If the decision to continue CPR is made, the placenta must be delivered, with gentle traction on the cord. Once the placenta is delivered, the endometrial cavity needs to be swept with a clean, moist Tintinalli_Sec11_p0607-0668.indd 646 8/2/19 4:21 PM