Nonobstetric emergencies in pregnancy: Trauma and surgical conditions

American Journal of

Obstetrics and

Gynecology F o u n d e d in i 9 2 0

v o l u m e 177

number 3

SEe-rS,MSSR 1997

PRIMARY CARE Nonobstetric emergencies in pregnancy: Trauma and surgical conditions Mary Thoesen Coleman, MD, PhD, Victor A. Trianfo, DO, and Douglas A. Rund, MD Columbus, Ohio Nonobstetric surgical emergencies may be difficult to recognize in pregnant patients whose normal physiologic state is altered by pregnancy. Early suspicion and serial examination in pregnancy may result in appropriate interventions for appendicitis, cholecystitis, pancreatitis, and bowel obstruction. Treatment in pregnant patients who experience trauma must be systematic so that situations at risk for maternal and fetal loss can be recognized. (Am J Obstet Gynecot 1997;177:497-502.)

Key words: Nonobstetric emergencies, pregnancy, appendicitis, cholecystitis, bowel obstruction, pancreatitis, arteriovascular malformation, aneurysm, trauma

The normal physiologic changes that occur in pregnancy may obscure recognition of nonobstetric emergencies which threaten the mother and fetus. Physiologic changes associated with pregnancy, such as increased abdominal girth, elevation of certain serum enzyme levels, and alteration of the adrenocortical state, may make it difficult to interpret signs usually used in early diagnosis of emergency conditions. Serial physical examinations, clinical awareness of potentially serious situations, and systematic evaluation can help to avert unnecessary maternal and fetal loss from surgical and traumatic conditions.

Surgical emergencies Gastroix~testinal surgical conditions Background. Approximately 1 in 500 pregnancies is complicated by a nonobstetric surgical condition. ~ Appendicitis, cholecystitis, pancreatitis, and bowel obstruction constitute the major surgical conditions. Xghen diagnosis is delayed, organs may rupture or sepsis may ensue, resulting in excess lactate producdon and acidosis. The most common nontraumatic and nonobstetric cause for surgery is acute appendicitis, 2 which occurs in 1 in 1500 pregnancies a and does not appear to be any more or less frequent than in the nongravid population. From the Departments ofFamily Medicine and EmergencyMedicine, The Ohio State University. Reprint requests: Mary Thoesen Coleman, MD, PJzD, Departments of Family Medicine and Emergency Medicine, 2231 North High St., Columbus, OH 43210. Copy,ight © 1997 by Mosby-Year Book, Inc. 0002-9378/97 $5.00 + 0 6/1/83052

In pregnancy, the appendix undergoes a progressive upward displacement, reaching the level of the iliac crest by the end of the sixth month. 4 Maternal morbidity correlates with perforation. In 1908, Babler 4~ stated, "The mortality of appendicitis complicating pregnancy is the morta!ity of delay." Maternal and fetal morbidit7 and mortality are associated with delay in diagnosis and pursuant complications) Fetal loss occurs in 3% to 5% of pregnant patients with appendicitis without perforation and in as many as 36% of cases when perforation is present. 3 Intestinal obstrttction is a complication in ! in 1500 to 1 in 3000 pregnancies. 6 The incidence increases sequentially throughout the pregnancy as the uterus increasingly encroaches on the abdominal cavity, with most obstructions occurring during the third trimester, y Adhesions from previous surgical interventions and pelvic inflammatory conditions are the cause of bowel obstruction. s Two other major causes are volvulus and intussusception with an incidence of 25% and 5%, respectively. Biliary disease in pregnancy can manifest as cholestasis, choiecystitis, choledocholithiasis, or gallstone pancreatitis. It is unclear whether the pregnant condition increases the incidence of galIstones. Asymptomatic cholelithiasis is reported to occur in 3.5% of pregnancies. Cholecystectomy is performed at approximately the same frequency as surgery for bowel obstruction during pregilancy, 5

Pancreatitis in pregnancy, occurring in 1 in 1000 to 1 in 5000, is probably not increased over the incidence in the nongravid state, l°,n The most common causes of pancreatitis are gallstones, medications, infections, alco497

498 Coleman, Trianfo, and Rund

hol, and hyperlipidemia. 12 The recognition of hyperlipidemia as a cause of pancreatitis in pregnancy is complicated by the fact that during pregnancy the cholesterol level increases by 25% to 50% and triglycerides increase threefold.~ a Presentation. Pregnant patients with appendicitis have colicky abdominal pain, which may be epigastric, periumbilical, or localized to the right side. By late pregnancy the appendix relocates closer to the gallbladder than McBurney's point, maldng diagnosis difficult.~2 Increased adrenocortical states associated with pregnancy may result in an elevation of the white blood cell count, cansing confusion as to the presence of inflammation. Anorexia, vomiting, rebound tenderness, and guarding may be present but are neither specific nor sensitive for the diagnosis of appendicitis. The differential diagnosis includes cholecystitis, urinary tract infections, pulmonary embolism, acute pancreatitis, and rightqower-lobe pneumonia along with obstetric concerns such as abruptio placentae, preeclampsia, and adnexal torsion. Some consider a calcified appendolith detected by ultrasonography diagnosticJ 4 The symptoms of cholecystitis are similar in both gravid and nongravid patients--nausea, vomiting, acute onset of colicky or stabbing midepigastric pain, or rightupper-quadrant pain. Tenderness under the right costal margin with deep inspiration may be present, as well as fever, tachycardia, and tachypnea. The differential diagnosis includes appendicitis, fatty liver of pregnancy, preeclarnpsia, HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome, myocardial infarction, pancreatitis, hepatitis, peptic ulcer disease, pneumonia, pyelonephritis, and herpes zoster. In cholecysfitis, elevated levels of direct bilirubin and transaminases may be present. Bilirubinuria also ma?, exist. Because the white blood cell count and alkaline phosphatase level increase in normal pregnancy, elevation of these may not be as helpful. Classic ultrasonographic findings of cholelithiasis, wall thickening, pericholecystic fluid, and ultrasonographic Murphy's sign are reliable in 90% of cases. 12' 14 Pancreatitis is characterized by severe epigastric pain that radiates to the back. Nausea, vomiting, and fever are common symptoms. Patients may try to decrease discomfort by assuming a position of flexed knees, hips, and trunk. Bowel sounds are usually diminished, and the abdomen is diffusely tender. Pancreatitis occurs more orten in the third trimester. ~3 An elevated amylase-tocreatinine clearance ratio is present in pregnant patients with pancreatids ~5 and may be more indicative of pancreatitis than amylase levels, which rise during pregnancy and also with cholecystitis, bowel obstruction, and ruptured ectopic pregnancy. When an appropriate acoustic window is found, ultrasonography may show dilated pancreatic ducts. The triad of abdominal pain, vomiting, and obstipa-

September 1997 «aanJ Obstet Gynecol

tion characterize bowel obstructions. Attacks of abdominal pain may occur evmT 4 to 5 minutes in cases of high obstruction; attacks usually occur with less frequency in colonic obstruction. Hypochloremic alkalosis as a result of emesis may develop. Occasionally, feculent and foulsmelling emesis may be present. The increased abdominal girth associated with obstruction is not easily distinguished from the effect of increased uterine growth. Serial upright and flat-plate x-ray films of the abdomen are 82% sensitive in the idendfication of either air fiuid levels or bowel dilatation, or both. 7 Management. Because morbidity and mortality are associated with delay in diagnosis and intervention, frequent serial examinations should be used to determine whether laparotomy is justified in a pregnant patient. Whether open or closed appendectomy is preferable is debated in the literature. Laparoscopic removal in the first trimester is being more widely performed. 14 Antibiotic coverage for suspected perforation includes broad gram-negative and anaerobic coverage. Most cases of cholecystitis can be managed with abstinence from oral intake and nasogastric suction, pain control, and antibiotics. Indications for surgery include failure to respond to conservative treatment, systemic toxicity, and recalcitrant pancreatitis. Surgery in the second trimester results in the best fetal outcome; intervention in the third trimester is associated with premarare labor. ~4 There is little experience with oral dissolution therapy in pregnant patients) 6 Laparoscopic cholecystectomy and endoscopic retrograde cholangiopancreatography with papillotomy are alternatives to traditional open cholecystectomy. 16 Pancreatitis in pregnancy is treated conventionally with oral abstinence, nasogastric suction, anatgesics, and intravenous feedings. Surgical interventions are reserved for those with abscess, ruptured pseudocyst, or hemorrhagic pancreatids. Endoscopic retrograde cholangiopancreatography with papillotomy may be appropriate for gallstone-induced pancreatitis? 6 Bowel obstrucfion is initially managed with fluid and electrolyte replacement and bowel decompression via nasogastric suction. Viability of the bowel can be determined only by inspection. ~ Aggressive intervention is warranted because maternal mortality can reach 20% and infant mortality more than double that. Net~rosurgical c o n d i t i o n s Background. Holcomb and Petrie, 17 in referencing Gibbs, state that 8% of maternal deaths are caused by cerebrovascular disease, which may be either hemorrhagic or occlusive in nature. The most common cause of intracranial hemorrhage during pregnancy (accounting for >50% of intracranial hemorrhages) is rupture of an anemTsm or arteriovenous malformation. Is Bleeding from an aneurysm is most commonly located in the subarachnoid space. Bleeding from an arteriovenous

Volume 177, Number3 ~~J Obstet C,ynecol

malformation is located within the brain parenchyma in about two thirds of cases with or without associated subarachnoid or intraventricular hemorrhage, m The risk of recurrent bleeding front an untreated aneurysm or arteriovenous malformation during the remainder of pregnancy is estimated at 33% to 50% and carries significant matemal mortality, s° Differential diagnoses for intracranial hemorrhage in pregnancy include pituitary apoplexy, intracranial venous or dural sinus thrombosis, and arterial occlusion. Presentation. A cerebral hemorrhage may result in sudden severe headache accompanied by transient loss of consciousness, diplopia, or vomiting. Usually, nuchal rigidity and positive Kernig's sign are present. It is not unusual for patients to have had less severe headaches during the previous weeks or months. Nearly 40% have no immediate focal neurologic deficits. 21 Management. If the diagnosis of intracranial hemorrhage from an aneulTsm or arteriovenous malformation is suspected clinically, computed tomographic scan without contrast (with proper shielding to reduce fetal risk) is necessary to confirm the diagnosis. If the computed tomographic scan falls to demonstrate subarachnoid bleeding, a lumbar puncture to detect blood in the cerebrospinal fluid may be performed. Cerebral angiography is required to characterize an anem7sm or arteriovenous malformation. Operative inte~'ention (clipping of the aneurysm) for aneurysmal hemorrhage has been shown to be beneficial during pregnancy. 22 The advantage of treating arteriovenous malformations with surgery in the pregnant patient is less clear. Traditional neurosurgical indications for operative intervention to treat arteriovenous malformations, such as evidence of previous hemorrhage, intractable epilepsy, severe, unrelenting headaches, and cerebrovascular ischemia caused by the "steat phenomenon" may also apply to gravid patients. The gravid state affects neurosurgical pharmacologic and fluid treatment. The use of anticomqy.lsants must be weighed against the risk of teratogenicity and is usually reserved for the perioperative period. Diuretics, offen used to control intracranial pressure, must be used with caution. Mannitol crosses the placenta and may accumulate, putting the fetus at risk for dehydration, bradycardia, and cyanosis.23 The efficacy of corticosteroids in the management of aneurysms and arteriovenous malformations has not been established. Trauma Bachground. Maternal trauma, the leading nonobstetric cause of fetal death, occurs in about 7% of pregnancies. 24 Motor vehicle accidents followed by falls and direct assaults to the abdomen account for the three most common causes of blunt trauma. Whereas the natural outcome in trauma is not affected

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by the pregnancy itself, fetal loss and abruptio placentae are disproportionately increased. Fetal losses as a result of abraptio placentae may be caused by an increase in intraamniotic pressure that deforms the elastic uterus around the relatively inetastic placenta and initiates a shearing effect of the placenta from the decidual basalis. Even in cases of minimal trauma, biochemical changes from maternal shock may precipitate abruptio placentae. "5 Major injuries (long bone fractures, rib fractures, or life-threatening injuries) may result in a 41% fetat loss. In contrast, fetal loss results from minor trauma about 1.7% of the time. 26 Significant fetal mortaliß may result from minor trauma, 27 so even apparently insignificant injuries, including those not involving the abdomen, should not be dismissed. Head in•nries and hemorrhagic shock are implicated in the majority of maternal deathsf 8 Trauma resulting from physical and sexual abuse has been reported in 1 of 10 woman3 s The Joint Commission on the Accreditation of Heatth Organizations recently advised that criteria be devetoped to aid in identi~ing the victims of abuse. ~~ Presentation. The mechanism of i n j u u is a particularly important part of the history m any trauma patient. including one who is pregnam. Information regarding weapon U, use of illicil drugs, and improper or lack of use of seat behs. should be songht. A positive toxicology screen can be found in up to 16% of patients tested. ~v Several physiologic changes have an impacL on the interpretation of physical examinations and laborato W data in the evaluation of pregnant women who have been subjected to trauma. Maternal blood volume increases about 1.ä L. -~°Because maternal plasma volume increases more than red blood cell mass during pregnancy, a decline in hematocrit is normally seen. During the second trimester, the uterus becornes an abdominal organ, subject to injmT from direct trauma. Blood flow to the uterus reaches about 600 m l / m i n . Therefore in the third trimester hemorrhage caused by blunt or penetra> ing injury may be brisk with risk of exsanguination.%~The bladder, normally protected by the symphysis in trauma, also attalns an intraabdominal position and therefore is more susceptible to injury. Decreased smooth muscle motilit,~ and delayed gastric emptying mcrease the risk of gastric aspiratiom Upperabdomina] injuries may perforate small bowe] disptaced upward by the gravid uterus. Decreased maternal sensitivi~, to peritoneal stimuli may diminish signals of injury usually present in the pbysical examinauon. Fetomaternal hemorrhage occurs four to five times more frequently in gravid patients who have been injured than in those who have not been injured. ~t Management. Management of the pregnant trauma patient begins udth following the guidelines ser by the resuscitarion mnemonic ABCDE, in which A stands for

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airway, B for breathing, C for circulation, D for disability or neurologic deficit, and E for exposure-environment. Thus securing an airway, administering oxygen, controlling bleeding, and replacing esfimated blood loss are the first steps. The securing of an airway in a pregnant patient carries with it an increased risk of emesis. For oral intubation, rapid-sequence induction with cricoid pressure and gastric decompression is suggested. Decreased breath sounds, subcutaneous emphysema, dyspnea, and hypotension suggest tension pneumothorax. When these clinical signs are present, needle aspiration at the second intercostal space along the midclavicular line or a closedtube thoracostomy at the third or fourth intercostal space (slightly higher than normal because of elevafion of the diaphragm during pregnancy) should be performed before a chest x-ray film or blood gas values are obtained. 24 Cardiovascular status should be assessed by serial pulse and blood pressure measurement. However, maternal blood pressure is not a good measure of uterine perfusion. 25 The pregnant patient at >20 weeks' gestafion is placed in the left lateral position to maintain venous return. The supine position may contribnte to hypotension. If a patient is immobilized on a backboard, folded sheets or pillows may be inserted as a wedge under the right side of the backboard. The uterus may also be deflected manually away from the vena cava. The Glasgow Coma Scale is useful in evaluating neurologic deficits. Head injuries and hemorrhagic shock are implicated in the majority of maternal deaths3 s Fluid resuscitation should be initiated through two large-bore antecubital catheters. The preferred cwstalloid is lactated Ringer's solution, administered in a ratio of 3:1 to estimated blood loss. Placement of intravenous lines in th e groin and lower extremity should be avoided if possible because of inferior vena cava syndrome and to avoid pooling in engorged or injured pelvic veins. Significant pelvic or femur fractures or hemothorax may necessitate early blood transfusion before overt clinical signs of hypovolemia develop. 24 Transfusion of typed and cross-matched Rh-compatibie blood or autotransfusion effectively replaces blood loss, but type-specific or type O-negative blood can be used if the former would significantly delay necessary transfusion. Vasopressors should be avoided if possible and should not be used in lieu of adequate volume replacement in trauma in pregnancy. Norepinephrine and epinephrine may restore maternal blood pressure hut severely reduce uterine flow. The vasopressors ephedrine and mephentermine elevate both maternal blood pressure and uterine flow. Dopamine at doses up to 5 b~g/kg per minute has little effect on uterine blood flow but does decrease it at doses >10 ixg/kg per minute. ä2

September 1997 Am J Obstet Gynecol

Evaluation of the patient who is refractory to volume resuscitation includes looking for inadequate resuscitative efforts, evaluating for retroperitoneal and uteroplacental blood loss, considering neurogenic shock and amniotic fluid embolization, and preparing for immediate operative intervention. Seconda U assessment. The head-to-toe physical assessment survey is performed, avoiding hypothermia, and is modified in the pregnant patient to include fetal assessment. Fetal assessment should begin with demonstration of fetal heart tones and estimation of age. Failure to detect heart tones with a stethoscope at 20 weeks' gestation or with a Doppler instrument at 10 to 14 weeks should be an indication for examination with real-time ultrasonography for fetal cardiac activity. Ultrasonography and fundal height may also be used to determine the gestational age, Cardiotocographic monitoring can detect fetal distress, 33 For fetuses >24 weeks old, continuous external monitoring should be used. 3s Fetal distress, as a sign of abruptio placentae, is more sensitive than abdominal pain and vaginal bleeding. Unfortunately, transabdominal ultrasonography has <50% accuracy in identifying abruptio p l a c e n t a e Y Foley catheter placement helps monitor urine output and fluid resuscitative efforts and establish the presence or absence of hematuria. Routine blood tests in a pregnant patient who has had trauma include hematocrit, hemoglobin, electrolytes, blood typing, coagulation studies, and arterial blood gases. Serum bicarbonate level may be an important indicator of adequate tissue perfusion and oxygen supply. Fetomaternal hemorrhage can be assessed with a Kleihauer-Betke preparation. As little as 1 ml of Rhpositive blood can sensitize 70% of an Rh-negative woman's blood. 34 Because the Kleihauer-Betke preparation requires a 5 ml hemorrhage to be sensitive at most laboratories, administration of 300 b~g of Rho(D) immunoglobulin is recommended. »4 Repeat Kleihauer-Betke testing is controversial. The routine radiographic screening series after trauma (cervical spine, chest, and pelvis with shielding), when limited to <25 rad, produces negligible exposure to the fetus. 35 These studies, if necessary, should be performed without delay. Abdominal and pelvic computed tomographic scans, along with intravenous pyelography and angiography, are performed as needed. If the mother is hemodynamically unstable or the fetus shows signs of distress, emergency cesarean delivery is indicated. If the need is less immediate, diagnostic peritoneal lavage may be useful, particularly in cases of blunt trauma and anterior abdominal and thoracoabdominal stab wounds. Computerized tomography also evaluates both retroperitoneal and intrauterine abnormality and is valuable in the evaluation of blunt abdominal trauma. Ultrasonography is reliable in screening for

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intraabdominal and pelvic fluid and can identify direct injury to peritoneal and retroperitoneal maternal structures. 24 In the late third trimester, as the fetus descends into the pelvis, direct fetal injuW including skull fraeture and contrecoup injuries can occur. These injuries are usually associated with maternal peMe fracmres. Surgical exploration is usually warranted for bullet wounds of the abdomen. 36 A fetal loss of 71% in gunshot wounds with a maternal mortaliß, of 3.9% has been reported, a3 Stab wounds may be managed differently, depending on gestational age, wound location, and fetal status, but still carry a high fetal mortality rate. 33 Discharge instructions for pregnant patients who have had minor trauma or insignifieant injuries should include caution about the development of severe abdominal pain or decreased fetal movement. Patients shou!d be instructed to immediately report vaginal bleeding or leakage of fluid. Timely obstetric follou~up should be advised. For the most serious of trauma cases, perimortem cesarean seetion is an option. Success is related to fetal maturity and length of time without maternal circulation. 37 Unfortunately, one study showed that only 15.3% of fetuses survived to be discharged home. 38

Comment Nonobstetric emergencies in pregnancy present a challenge to health eare providers who taust remain cognizant that the normal physiologie state of pregnancy causes alterations in presentation and management of many clinical situations. It is important for elinicians to keep these alterations in mind, first, to be able to recognize hypotension, h)qooxia, and acidosis in the gravid patient and, second, to be able to appropriately manage them.

Key points • By late pregnancy the relocation of the appendix closer to the gallbladder than McBurney's point may make diagnosis of appendicitis diflqcult. • Tests, in addition to frequent serial physical examinations, which may be nsefnI in the diagnosis of appendicitis in pregnancy, include ultrasonography and the amylase/creatinine ratio. • Serial upright and flat-plate radiographs of the abdornen are 82% sensitive in the identification of air fluid leve]s or bowel dilatation. • The best fetal outcome from cholecystectomy occurs in the second trimester and is indicated when systemic toxicity develops in patients without a response to conservative treatment of cholecystitis (abstinence from oral intake, nasogastric suction, pain control, and antibiotics) or with recalcitrant pancreatitis. ù Surgical intervention for pancreatitis in pregnancy is

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reserved for those with abscesses, ruptured pseudocysts, or hemorrhagic pancreatitis. • Pregnant patients who undergo trauma are treated aceording to the ABCDE guidelines, with a few special additions, including use of rapid-sequence induction with cricoid pressure and gastric deeompression when oral intubation is indicated, closedtube thoracotomy at a higher levet (the third or fourth intercostal space) when treating for pneumothorax, and placement of the patient who is >20 weeks' gestation in the left lateral position to maximize venous return. Placement of intravenous lines in the groin and lower extremity should be avoided if possible because of inferior cava syndrome and to avert pooling in engorged or injured pelvic veins. • Fetal assessment for fetal distress and abruptio placentae ma}' be best assessed by cardiotocographic monitoring, which should be performed continuously for fetuses at >24 weeks of age. • There is very little risk to the fetus when exposure to radiographs is limited to <25 rad. The routine screening radiograph series after trauma (cervical spine, chest, and peMs with shielding) produces negligible exposure to the fetus. ® Surgery may be warranted when there are signs of maternal hemodynamic instability, fetal distress, bullet wounds to the abdomen, or mddence of cerebra| aneurysmal hemorrhage.

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