Clinical Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jan 28, 2006; 12(4): 582-587
Published online Jan 28, 2006. doi: 10.3748/wjg.v12.i4.582
Distal small bowel motility and lipid absorption in patients following abdominal aortic aneurysm repair surgery
Robert J Fraser, Marc Ritz, Addolorata C Di Matteo, Rosalie Vozzo, Monika Kwiatek, Robert Foreman, Brendan Stanley, Jack Walsh, Jim Burnett, Paul Jury, John Dent
Robert J Fraser, Department of Medicine, University of Adelaide, South Australia
Marc Ritz, Addolorata C Di Matteo, Rosalie Vozzo, John Dent, Department of Gastroenterology, Royal Adelaide Hospital, Adelaide, South Australia
Paul Jury, Vascular Unit, Royal Adelaide Hospital, Adelaide, South Australia
Monika Kwiatek, Gastrointestinal Investigation Unit, Repatriation General Hospital, Daw Park, South Australia
Robert Foreman, Brendan Stanley, Jack Walsh, Jim Burnett, Vascular Unit, Repatriation General Hospital, Daw Park, South Australia
Supported by National Health and Medical Research Council of Australia, and Margarete and Walther Lichenstein - Stiftung (Basel, Switzerland)
Correspondence to: Robert J Fraser, Associate Professor, Investigation and Procedures Unit, Repatriation General Hospital, Daw Park, Adelaide 5041, South Australia. robert.fraser@rgh.sa.gov.au
Telephone: +61-8-8275-1977 Fax: +61-8-8275-1083
Received: July 12, 2005
Revised: July 15, 2005
Accepted: August 3, 2005
Published online: January 28, 2006
Abstract

AIM: To investigate distal small bowel motility and lipid absorption in patients following elective abdominal aortic aneurysm (AAA) repair surgery.

METHODS: Nine patients (aged 35-78 years; body mass index (BMI) range: 23-36 kg/m2) post-surgery for AAA repair, and seven healthy control subjects (20-50 years; BMI range: 21-29 kg/m2) were studied. Continuous distal small bowel manometry was performed for up to 72 h, during periods of fasting and enteral feeding (Nutrison®). Recordings were analyzed for the frequency, origin, length of migration, and direction of small intestinal burst activity. Lipid absorption was assessed on the first day and the third day post surgery in a subset of patients using the 13C-triolein-breath test, and compared with healthy controls. Subjects received a 20-min intraduodenal infusion of 50 mL liquid feed mixed with 200 μL 13C-triolein. End-expiratory breath samples were collected for 6 h and analyzed for 13CO2 concentration.

RESULTS: The frequency of burst activity in the proximal and distal small intestine was higher in patients than in healthy subjects, under both fasting and fed conditions (P < 0.005). In patients there was a higher proportion of abnormally propagated bursts (71% abnormal), which began to normalize by d 3 (25% abnormal) post-surgery. Lipid absorption data was available for seven patients on d 1 and four patients on d 3 post surgery. In patients, absorption on d 1 post-surgery was half that of healthy control subjects (AUC 13CO2 1 323 ± 244 vs 2 646 ±365; P < 0.05, respectively), and was reduced to the one-fifth that of healthy controls by d 3 (AUC 13CO2 470 ± 832 vs 2 646 ± 365; P < 0.05, respectively).

CONCLUSION: Both proximal and distal small intestinal motor activity are transiently disrupted in critically ill patients immediately after major surgery, with abnormal motility patterns extending as far as the ileum. These motor disturbances may contribute to impaired absorption of enteral nutrition, especially when intraluminal processing is necessary for efficient digestion.

Keywords: Critical illness; Small intestine; Motility; Lipid absorption