Research

The impact of admission diagnosis on gastric emptying in critically ill patients

Nam Q Nguyen^1,2 , Mei P Ng¹ , Marianne Chapman³ , Robert J Fraser² and Richard H Holloway^1,2

¹Department of Gastroenterology, Royal Adelaide Hospital, North Terrace, Adelaide, 5000, Australia

²Department of Medicine, University of Adelaide, Frome Road, Adelaide, 5000, Australia

³Department of Intensive Care, Royal Adelaide Hospital, North Terrace, Adelaide, 5000, Australia

author email corresponding author email

Critical Care 2007, 11:R16doi:10.1186/cc5685

Published:	8 February 2007

Abstract

Introduction

Disturbed gastric emptying (GE) occurs commonly in critically ill patients. Admission diagnoses are believed to influence the incidence of delayed GE and subsequent feed intolerance. Although patients with burns and head injury are considered to be at greater risk, the true incidence has not been determined by examination of patient groups of sufficient number. This study aimed to evaluate the impact of admission diagnosis on GE in critically ill patients.

Methods

A retrospective review of patient demographics, diagnosis, intensive care unit (ICU) admission details, GE, and enteral feeding was performed on an unselected cohort of 132 mechanically ventilated patients (94 males, 38 females; age 54 ± 1.2 years; admission Acute Physiology and Chronic Health Evaluation II [APACHE II] score of 22 ± 1) who had undergone GE assessment by ¹³C-octanoic acid breath test. Delayed GE was defined as GE coefficient (GEC) of less than 3.20 and/or gastric half-emptying time (t50) of more than 140 minutes.

Results

Overall, 60% of the patients had delayed GE and a mean GEC of 2.9 ± 0.1 and t50 of 163 ± 7 minutes. On univariate analysis, GE correlated significantly with older age, higher admission APACHE II scores, longer length of stay in ICU prior to GE measurement, higher respiratory rate, higher FiO₂ (fraction of inspired oxygen), and higher serum creatinine. After these factors were controlled for, there was a modest relationship between admission diagnosis and GE (r = 0.48; P = 0.02). The highest occurrence of delayed GE was observed in patients with head injuries, burns, multi-system trauma, and sepsis. Delayed GE was least common in patients with myocardial injury and non-gastrointestinal post-operative respiratory failure. Patients with delayed GE received fewer feeds and stayed longer in ICU and hospital compared to those with normal GE.

Conclusion

Admission diagnosis has a modest impact on GE in critically ill patients, even after controlling for factors such as age, illness severity, and medication, which are known to influence this function.