ABDOMINAL PAIN IN PREGNANCY

ABDOMINAL PAIN IN PREGNANCY District 1 ACOG Medical Student Teaching Module 2011

Challenge of Abdominal Pain During Pregnancy • Multiple causes including essentially all non pregnancy causes plus obstetric causes • Clinical presentation & natural history often altered with pregnancy • Diagnostic evaluation and treatment plans altered & limited • Fetal wellbeing to be considered

Obstetric/Gynecologic Etiologies • Ruptured Ectopic • Pre-eclampsia/Eclampsia • Placental Abruption • Uterine Rupture • Ovarian Cyst Rupture • PID • Tubo-Ovarian Abscess • Uterine Leiomyomas • Abortion • Salpingitis • Endometriosis • Cancer of Cervix or Ovary

Common Non OB Etiologies • GERD/other bowel c/o • Intestinal Obstruction • Cholelithiasis/Cholecystitis • Pancreatitis • Pyelonephritis • Nephrolithiasis • Appendicitis

HISTORY • As with most things, history essential to diagnosis: -Location -Character -Radiation -Aggravating/Relieving Factors

PHYSICAL EXAM • Uterus displaces abdominal organs • Moving omentum does not wall off infection as well • Late pregnancy abdominal wall laxity may mask rigid abdomen of peritonitis

GERD • Up to 80% in pregnancy • Gastric compression by uterus, hypotonic LES, & gastrointestinal dysmotility • Epigastric discomfort, nausea, emesis, anorexia, regurgitation, water brash • PUD decreases secondary to decreased gastric secretion, decreased motility, & increased mucus secretion

Treatment of GERD • Lifestyle modifications • H2 Blockers (Ranitidine) • PPI’s (Losec) • Consider deferring H Pylori eradication until PP because of possible teratogenic effects of certain medication regimes • Surgery for GERD best delayed until PP • Esophagogastroduodenoscopy (EGD) for bleeding & surgery if unstable as fetus tolerates maternal hypotension poorly • In advanced pregnancy, c/s before gastric surgery for bleeding

Intestinal Obstruction • Second most common nonobstetrical abdominal emergency (>1/1500) • Incidental or secondary to pregnancy • Large increase in #’s results from increased #’s abdominal procedures, PID, & # pregnancies in older women • Most common T3 b/c mechanical effects large uterus, fetal head descent or immediately PP because rapid change uterine size • Adhesions (previous surgery) 60-70% SBO

Intestinal Obstruction cont … • AXR required to dx & monitor despite risk radiation to fetus • Surgery for complete/unremitting • Medical tx for partial/intermittent -IV fluid & lyte correction -NGT to suction -Morbidity/mortality related to delayed dx -Maternal < 6% -Fetal 20-30% -Maternal 13% in colonic volvulus

Cholelithiasis • Pregnancy increases bile lithogenicity & sludge formation b/c estrogen increases cholesterol synthesis and progesterone impairs gallbladder motility • >12% pregnancy compared to 1-2% controls • Pregnancy does not increase severity of complications • Most gallstones are asymptomatic

Cholelithiasis • Symptoms: -Biliary colic in epigastrium/RUQ -May radiate to back, flank, or shoulders -pain often associated with post prandial states (especially fatty foods) -Pain typically lasts 1 to several hours -Diaphoresis, nausea, & emesis common Physical exam often unremarkable apart from occasional RUQ tenderness

Cholelithiasis • 1/3 patients no additional episode X 2 yrs • Complications of cholelithiasis include cholecystitis, choledocholithiasis, jaundice, cholangitis, biliary stricture, sepsis, abscess, empyema, gallbladder perforation, & gallstone pancreatitis

Cholecystitis • Inflammation usually caused by cystic duct obstruction & supersaturated bile • 3rd most common nonobstetric surgical emergency • 1-8/10,000 • Same symptoms but pain more prolonged • Often get tachycardia, fever, R subcostal tenderness, & Murphy’s sign • Leukocytosis common • Serum LFT’s may be slightly abnormal • Jaundice may suggest choledocholithiasis

Tx for Cholecystitis • Cholecystectomy • Pre-op NPO, IV fluid, abx • Abdominal surgery best in T2 • T1 associated with fetal abortion & T3 with premature labor • Cholecystectomy may be deferred in appropriate cases • Lap chole safe in earlier pregnancy • Intraoperative cholangiography only for strong indications • Maternal & fetal mortality < 5%

Choledocholithiasis • Abdominal pressure & jaundice • Endoscopic u/s • Fever/chills, leukocytosis, n&v • ERCP & sphincterotomy with cholecystectomy PP

Pyelonephritis • Renal alterations in 70-90% • More pronounced T2 & T3 when risk pyelonephritis is greatest • Asymptomatic bacteriuria (ASB) in about 7% • Acute cystitis 2% • ASB treated to prevent pyelonephritis (cephalosporins, nitrofurantoin …) • 25-40% untreated ASB develop pyelo • 30% retreatment

Pyelonephritis • Acute pyelo in 1-2% pregnancies • Symptoms & Signs: -Fever/chills -N & V -Flank pain -CVA tenderness -Complications include sepsis, shock, ADRS, Pulmonary edema, renal insufficiency/abscess, & recurrent infection

Pyelonephritis • Tx is IV abx until patient clinically improves and then PO abx • Renal u/s if no improvement after 3 days • Associated with preterm labor and delivery

Nephrolithiasis • Symptomatic < 5/1000 pregnancies but accounts for the most nonobstetric hospitalizations • About 50% causes by hypercalciuria • Usually T2 or T3 • Symptoms & Signs : -Abdominal/flank pain often radiating to groin -Gross hematuria, urgency, frequency -N&V, diaphoresis, fever/chills

Nephrolithiasis • Fluoroscopy relatively contraindicated • U/S initial test of choice • Tx includes hydration, analgesia, & abx if infection – most responds well • Obstruction, sepsis requires ureteral stent • Surgery in refractory cases • Risk premature labor

Acute Pancreatitis • 0.1-1% pregnancies • Most common T3 & PP • Gallstones cause > 70% • EtOH quite uncommon but other causes include drugs, surgery, trauma, etc • Pregnancy does not affect • Epigastric pain most common complaint • Pain may radiate to back, shoulders, or flanks • Nausea, emesis, fever common

Acute Pancreatitis cont … • Signs: -Midabdominal tenderness -Occasional rebound -Guarding -Hypoactive BS -Distension -Tympany

Acute Pancreatitis cont … • Elevated Amylase & Lipase • U/S for cholelithiasis & bile duct dilation • Endoscopic u/s for choledocholithiasis • Pancreatitis in pregnancy usually mild and responds well to medical therapy -NPO -IV fluids -Gastric acid suppression -Analgesia (Meperidine) -? NGT suction

Acute Pancreatitis cont … • Severe pancreatitis with abscess, sepsis, phlegmon requires ICU, Abx, TPN, & possible radiologic/surgical intervention • Pregnancy should not delay CT or surgery in these cases • Endoscopic spincterotomy can be performed during pregnancy with minimal fetal radiation exposure • Maternal mortality low with uncomplicated but > 10% with complicated pancreatitis • T1 – fetal abortion ; T3 – preterm labor

APPENDICITIS • Most common nonobstetric surgical emergency (1/1000) in pregnancy • Appendicitis in 1/1500 (65%) • Slightly more likely during T2 • Maternal mortality (highest in T3) somewhat higher secondary to delayed dx and decline of laparotomy (0.1% without perforation & 4% with perforation)

Appendicitis cont … • Up to 25% develop appendiceal perforation • Fetal complications mostly secondary to preterm labor (1-2% in uncomplicated appendicitis and 30-40% with peritonitis)

Appendicitis cont … Symptoms: -Periumbilical (early visceral obstructive) -RLL/RUQ (late parietal secondary inflammation) – very focal -N & V, anorexia, urinary frequency Signs: -Focal tenderness/guarding /rebound/ ?peritoneal signs (omental displacement)

Appendicitis cont … • Investigations: -Leukocytosis normal in pregnancy -U/S nonspecific but may show appendiceal mural thickening & periappendiceal fluid (mostly to help r/o other etiologies) -CT better but exposes fetus to radiation -Often confused with right pyelonephritis/cholecystitis

Appendicitis Management • APPENDICITIS REQUIRES SURGERY • IV hydration & lytes correction • Abx (Penicillin, Cephalosporins, Clinda, Gent) • Laparoscopy in T1 & ? T2 for nonperforated • Laparotomy incision over pt of focal tenderness • Appendectomy even if no appendicitis • Concomitant c/s not done

ABDOMINAL PAIN IN PREGNANCY