Ronald J Wapner

Complications of anesthesia for cesarean delivery

Objective: To quantify anesthesia-related complications associated with cesarean delivery in a well-described, prospectively ascertained cohort from multiple university-based hospitals in the United States and to evaluate whether certain factors would identify women at increased risk for a failed regional anesthetic. Methods: A prospective observational study was conducted of women (n = 37,142) with singleton gestations undergoing cesarean delivery in the centers forming the National Institute of Child Health and Human Development Maternal–Fetal Medicine Units Network. Detailed information was collected regarding choice of anesthesia and procedure-related complications, including failed regional anesthetic and maternal death. Potential risk factors for a failed regional anesthetic were analyzed. Results: Of the women studied, 34,615 (93%) received a regional anesthetic. Few (3.0%) regional procedures failed, and related maternal morbidity was rare. Increased maternal size, higher preoperative risk, rapid decision-to-incision interval, and placement later in labor were all significantly related to an increased risk of a failed regional procedure. Of the general anesthetics, 38% were administered when the decision-to-incision interval was less than 15 minutes. Women deemed at the greatest preoperative risk (American Society of Anesthesiologists score ≥ 4) were approximately 7-fold more likely to receive a general anesthetic (odds ratio 6.9, 95% confidence interval 5.83–8.07). There was one maternal death, due to a failed intubation, in which the anesthetic procedure was directly implicated. Conclusion: Regional techniques have become the preferred method of anesthesia for cesarean delivery. Procedure-related complications are rare and attest to the safety of modern obstetric anesthesia for cesarean delivery in the United States. Level of Evidence: II-2

Spontaneous resolution of asymptomatic Chlamydia trachomatis in pregnancy

OBJECTIVE: We sought to estimate the rate of spontaneous resolution of asymptomatic Chlamydia trachomatis in pregnancy and to evaluate factors associated with its resolution. METHODS: A cohort of women enrolled in a large multicenter randomized bacterial vaginosis antibiotic trial (metronidazole versus placebo) that, when randomly allocated, had asymptomatic C trachomatis diagnosed by urine ligase chain reaction (from frozen archival specimens) between 160/7 and 236/7 weeks were included. The urine ligase chain reaction is a highly accurate predictor of genital tract chlamydial infection. A follow-up ligase chain reaction was performed between 240/7 and 296/7 weeks. RESULTS: A total of 1,953 women were enrolled in the original antibiotic trial; 1,547 (79%) had ligase chain reaction performed both at randomization and follow-up. Women receiving antibiotics effective against Chlamydia between randomization and follow-up or having symptomatic Chlamydia infection were excluded (26 women). Of the 140 women (9%) who were diagnosed as positive via the initial ligase chain reaction assay, 61 (44%) had spontaneous resolution of Chlamydia by the follow-up ligase chain reaction assay. Factors associated with spontaneous resolution included older age (P = .02), more than 5 weeks from randomization to follow-up (P = .02), and a greater number of lifetime sexual partners (P = .02). Using a logistic regression model, maternal age and a greater-than-5-week follow-up interval remained significant; for every 5-year increase in maternal age, the odds of a positive result on the ligase chain reaction test at follow-up decreased by 40% (odds ratio 0.6; 95% confidence interval 0.4–0.9). Race, substance abuse, parity, and treatment with metronidazole were not associated with spontaneous resolution. Gram stain score and vaginal pH at randomization and follow-up also were not associated. CONCLUSION: The prevalence of asymptomatic C trachomatis in pregnancy was 9%; infection resolved spontaneously in almost half of these women. The association of older age and increasing time interval to spontaneous resolution of Chlamydia is consistent with a host immune-response mechanism. LEVEL OF EVIDENCE: III