Rapid correction of metabolic alkalosis in hypertrophic pyloric stenosis with intravenous cimetidine: preliminary results

Abstract

Purpose: Pyloromyotomy has been the treatment of choice for hypertrophic pyloric stenosis (HPS) for the past century. In most HPS cases, there is mild metabolic alkalosis, which requires intravenous fluid resuscitation with 5% dextrose/normal saline for 1-2 days. However, in some cases, due to a delay in diagnosis, alkalosis becomes severe and a much longer resuscitation period (5-10 days) is required to normalize serum pH. Metabolic alkalosis of HPS results from excessive vomiting of hydrochloric acid; and therefore if its production is reduced, serum pH can be normalized faster. In this study, the use of intravenous cimetidine (CM) in a small number of infants with HPS is presented.

Methods: Over a 28-month period, 32 HPS cases, including a sub-group of 17 infants (aged 7-9 weeks) with arterial pH >7.60, were admitted to a tertiary referral unit. Four infants in this sub-group were treated with standard resuscitation fluids for 4 days prior to intravenous CM, while 12 infants received CM immediately. Intravenous CM (10 mg/kg) was given at twice daily until arterial pH was less than 7.50. In one case, intravenous omeprazole at 0.1 mg/kg was given instead of CM.

Results: In all 17 cases, CM treatment or omeprazole therapy (for 12-48 h) reduced pH to less than 7.50, thus allowing for Ramstedt pyloromyotomy the same day. These patients were allowed oral feeding on the following day and were discharged at 1-3 post-operative days. No complications due to CM (or omperazole) treatment were observed.

Conclusion: Intravenous CM administration can rapidly normalize severe metabolic alkalosis in HPS patients. As a result, pyloromyotomy can be performed sooner reducing both hospital stay and costs.