Pulmonary injury associated with appendicitis in pregnancy: who is at risk?

Our purpose was to determine risk factors for pulmonary injury in women with antepartum appendicitis.

This case-control study included 49 patients with appendicitis during pregnancy. Patients who had pulmonary injury composed the study group (n = 9); the control subjects had no injury (n = 40). Records were abstracted for gestational age at surgery, type of anesthesia, presenting symptoms, findings on physical examination, vital signs, laboratory test results, use of tocolytics or antibiotics, and fluid management. Pulmonary injury was characterized by dyspnea, tachypnea, PaO2 < or = 70 mm Hg, and an abnormality on chest radiography.

Pulmonary injury developed in nine study patients (18%) (adult respiratory distress syndrome, n = 2; pulmonary edema or infiltrates, n = 7) as a complication of appendicitis during pregnancy. All study group patients were at > 20 weeks' gestation compared with 27 of 40 (67%) control subjects (p = 0.05). Univariate analysis showed that fluid overload > or = 4 L, maximum respiratory rate > 24 breaths/min, maximum heart rate > 110 beats/min, maximum temperature > or = 100.4 degrees F, general anesthesia, and tocolytic use were significant (p < 0.005). By multivariate analysis with the use of stepwise logistic regression a model of fluid overload > or = 4 L, respiratory rate > 24 breaths/min, maximum temperature > or = 100.4 degrees F, and tocolytic usage would predict 99% of injury cases.

Iatrogenic factors such as injudicious fluid management and tocolytic use can greatly increase the risk for pulmonary injury with antepartum appendicitis.