CME Author: Hien T. Nghiem, MD
Appendectomy for suspected appendicitis during pregnancy increased risk for adverse fetal outcomes even when the appendix was normal, according to the results of a retrospective analysis reported in the October issue of the American College of Surgeons.
“The preoperative diagnosis of acute appendicitis is often inaccurate in pregnant women, and complicated appendicitis is associated with a high rate of fetal loss,” write Marcia L McGory, MD, from the David Geffen School of Medicine at the University of California Los Angeles, and colleagues. “The study objective was to evaluate rates of fetal loss and early delivery in pregnant patients undergoing appendectomy, using a large population-based database.”
The investigators used the California Inpatient File for retrospective analysis of all women undergoing appendectomy between 1995 and 2002. Data analyzed included pregnancy status, diagnosis, operative technique, fetal loss, and early delivery during the same hospitalization as appendectomy.
Of 94,789 women who underwent appendectomy, 3133 were pregnant; 30% of pregnant women and 29% of nonpregnant women had complicated appendicitis (P = not significant). Compared with nonpregnant women, pregnant women had a higher rate of negative appendectomy (23% vs 18%; P < .05).
Rates of fetal loss and early delivery were increased in pregnant women with complex appendicitis (6% and 11% respectively; P < .05) vs in pregnant women with negative (4% and 10%) and simple (2% and 4%) appendicitis. Complicated and negative appendicitis (odds ratio [OR], 2.69 and 1.88, respectively, vs simple) were major positive predictors of fetal loss, according to the results of multivariate logistic regression. Compared with open appendectomy, laparoscopy was associated with an increased rate of fetal loss (OR = 2.31).
“The current approach to possible acute appendicitis in pregnant women puts 23% at risk for fetal loss, even though they have a normal appendix,” the authors write. “These data indicate that reducing fetal loss in pregnant women suspected of having acute appendicitis will require more accurate diagnosis to avoid unnecessary operation.”
Study limitations include inability to determine the time of gestation; possible underestimate of the rate of early delivery after appendectomy; possible miscoding of some procedures and diagnoses; missing clinical data; possible confounding variables; outcomes of fetal loss and early delivery limited to the inpatient hospitalization at the time of appendectomy; and lack of generalizability to states other than California.
“We have shown that appendectomy during pregnancy is associated with a considerable risk to the fetus both from fetal loss and early delivery,” the study authors conclude. “The risk to the fetus appears higher with laparoscopic appendectomy, although the risk to the fetus is substantial even when the appendix is normal. Finally, because the incidence of ruptured appendicitis is almost identical in pregnant and nonpregnant women, it appears that the greatest opportunity to improve fetal outcomes is by improving diagnostic accuracy and reducing the rate of negative appendectomy in pregnant women.”
Clinical Context
The preoperative diagnosis of acute appendicitis is often inaccurate in 25% to 50% in pregnant women. One recent review reported the overall diagnostic accuracy for appendicitis in pregnant women was 75.3%, but it varied widely between hospitals. The reasons behind the incorrect preoperative diagnosis are that appendicitis can be difficult to diagnose in women and the clinical presentation is often altered in pregnant women, particularly those close to term. The low diagnostic accuracy rate has been accepted as a consequence of an aggressive surgical strategy to minimize the risk for maternal mortality and fetal loss associated with ruptured appendicitis. Currently, maternal mortality has all but disappeared; however, complicated appendicitis is associated with a high rate of fetal loss.
The aim of this study was to evaluate rates of fetal loss and early delivery in pregnant patients undergoing appendectomy, using a large population-based database.
