An analysis of bowel obstruction following cesarean birth
Investigating whether the choice of vasopressor during caesarean birth affects the risk of acute colonic pseudo-obstruction and ileus
Acute colonic pseudo-obstruction (ACPO) following caesarean birth is a serious but rare complication that can lead to bowel perforation, emergency surgery, and significant maternal morbidity. Despite this, bowel outcomes have never been examined in any of the randomised trials comparing vasopressors for caesarean birth, including the most recent network meta-analysis of 55 trials and nearly 5,500 patients. Our preliminary service evaluation of nearly 7,000 caesarean births over three years found a stable ileus rate of 4% but a tenfold increase in ACPO following a unit-wide change in routine vasopressor from phenylephrine to noradrenaline. This increase included a fivefold rise in cases requiring colonoscopic decompression or surgery, outcomes that cannot be explained by changes in diagnostic practice alone.
This project will strengthen these preliminary findings through individual-level chart review of all affected cases and electronic health record analysis of the full cohort, aiming to confirm vasopressor exposure, exclude alternative explanations, and provide the evidence base needed to inform vasopressor choice in obstetric anaesthesia practice.