Evaluation of Routine Administration of Glycerin Suppositories to Improve Bowel Function in Patients With Uncomplicated Gastroschisis

Gastroschisis is a congenital defect of the abdominal wall that leads to evisceration of various amounts of the abdominal organs. The mainstay of therapy is restoring continuity of the abdominal wall, either through primary closure or with a synthetic graft when primary closure is not feasible. Closure of the abdominal cavity is confounded by prenatal loss of abdominal domain coupled by resultant swelling of the abdominal viscera due to prenatal exposure to amniotic fluid. Additionally, some patients with gastroschisis have other concomitant abnormalities of the bowel (termed complicated gastroschisis) that require additional surgical intervention.

It has been established that bowel function after repair of gastroschisis is impaired due to the aforementioned pathological processes. Previous studies have shown that the time from surgery to attaining full nutrition through enteral means is a predictor for morbidity in this population. Therefore, numerous therapeutic interventions have been proposed to help hasten bowel function and decrease the time to tolerance of total enteral nutrition. A common, but unproven, technique is the use of glycerin suppositories to stimulate bowel function. The concept of glycerin suppositories is that stimulating colonic activity through the use of the suppository will stimulate small intestinal function. The underlying concept is that improved bowel motility and reduced time to full enteral feeds will reduce the morbidity associated with this disease. While the formation/evacuation of stools is most easily monitored, the main purpose of using these suppositories is to hasten tolerance of nutrition through enteral means.

While the practice of using glycerin suppositories is common in neonates, there is no literature or best-practice guidelines advocating for (or against) their use. A single previous prospective study utilizing glycerin suppositories in premature, low birth weight neonates failed to show any benefit in improving time to tolerate full enteral feeds. At this time, this is the only study investigating the use of glycerin suppositories in any neonatal population, and due to the indications (i.e. premature and low birth weight infants without surgical disease), the findings are not applicable to neonates with gastroschisis. To the authors' knowledge, there are no previous studies or current ongoing studies examining this question. Given this lack of information regarding the efficacy of glycerin suppositories, there is a significant variation in practice among practicing surgeons, including timing of initial administration, frequency of use, and indication to discontinue. Indeed the spectrum ranges from some surgeons who never use glycerin suppositories, to some who prescribe them daily for all gastroschisis patients immediately following surgery.

The purpose of this study will be to determine whether routine use of glycerin suppositories improves bowel function as measured by time to full enteral feeds (primary outcome: defined as enteral feed volume >120mL/kg/day with appropriate weight gain (20-30g/day for two consecutive days)) in neonates with uncomplicated gastroschisis after complete reduction of abdominal viscera. Secondary outcomes include time to first bowel movement and incidence/severity of TPN-induced cholestasis in the study groups.

Individuals will be followed from the time of consultation by the Pediatric General Surgery service (i.e. at the time of birth) until initial discharge. Neonates undergo abdominal wall closure and reach full nutrition (via either full enteral, total parenteral nutrition, or a combination of both) prior to discharge.