Systematic Reviews
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. Jul 27, 2016; 8(7): 521-532
Published online Jul 27, 2016. doi: 10.4240/wjgs.v8.i7.521
Benefits of post-operative oral protein supplementation in gastrointestinal surgery patients: A systematic review of clinical trials
Mike Crickmer, Colum P Dunne, Andrew O’Regan, J Calvin Coffey, Suzanne S Dunne
Mike Crickmer, Colum P Dunne, Andrew O’Regan, J Calvin Coffey, Suzanne S Dunne, Graduate Entry Medical School, University of Limerick, Castletroy, V94 T9PX Limerick, Ireland
Mike Crickmer, Colum P Dunne, Andrew O’Regan, J Calvin Coffey, Suzanne S Dunne, Centre for Interventions in Infection, Inflammation and Immunity (4i), University of Limerick, Castletroy, V94 T9PX Limerick, Irelan
J Calvin Coffey, Department of Surgery, University Hospital Limerick, V94 T9PX Limerick, Ireland
Author contributions: All authors contributed equally to the work; Crickmer M and Dunne CP conceived the study; Crickmer M, Dunne CP and Coffey JC designed the search; Crickmer M, O’Regan A and Dunne SS performed the searches and analysed the data; all authors contributed to drafting of the manuscript.
Conflict-of-interest statement: The authors confirm that they have no conflicts of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Colum P Dunne, Professor, Graduate Entry Medical School, University of Limerick, Castletroy, V94 T9PX Limerick, Ireland. colum.dunne@ul.ie
Telephone: +353-061-234703
Received: February 11, 2016
Peer-review started: February 14, 2016
First decision: March 21, 2016
Revised: April 5, 2016
Accepted: April 21, 2016
Article in press: April 22, 2016
Published online: July 27, 2016
Abstract

AIM: To evaluate published trials examining oral post-operative protein supplementation in patients having undergone gastrointestinal surgery and assessment of reported results.

METHODS: Database searches (MEDLINE, BIOSIS, EMBASE, Cochrane Trials, Cinahl, and CAB), searches of reference lists of relevant papers, and expert referral were used to identify prospective randomized controlled clinical trials. The following terms were used to locate articles: “oral’’ or “enteral’’ and “postoperative care’’ or “post-surgical’’ and “proteins’’ or “milk proteins’’ or “dietary proteins’’ or “dietary supplements’’ or “nutritional supplements’’. In databases that allowed added limitations, results were limited to clinical trials that studied humans, and publications between 1990 and 2014. Quality of collated studies was evaluated using a qualitative assessment tool and the collective results interpreted.

RESULTS: Searches identified 629 papers of which, following review, 7 were deemed eligible for qualitative evaluation. Protein supplementation does not appear to affect mortality but does reduce weight loss, and improve nutritional status. Reduction in grip strength deterioration was observed in a majority of studies, and approximately half of the studies described reduced complication rates. No changes in duration of hospital stay or plasma protein levels were reported. There is evidence to suggest that protein supplementation should be routinely provided post-operatively to this population. However, despite comprehensive searches, clinical trials that varied only the amount of protein provided via oral nutritional supplements (discrete from other nutritional components) were not found. At present, there is some evidence to support routinely prescribed oral nutritional supplements that contain protein for gastrointestinal surgery patients in the immediate post-operative stage.

CONCLUSION: The optimal level of protein supplementation required to maximise recovery in gastrointestinal surgery patients is effectively unknown, and may warrant further study.

Keywords: Protein supplementation, Gastrointestinal surgery, Clinical trial, Oral supplementation, Systematic review

Core tip: Malnutrition in hospitalized patients can negatively impact recovery; protein and energy deficiencies have been documented in gastrointestinal surgery patients and trials have demonstrated benefits of perioperative nutritional strategies, although post-operative oral nutritional supplementation have been studied to a lesser extent. The outcome of our work is that clinical trials that varied only the protein provided via oral supplements were not found. There is evidence to support oral protein supplements for gastrointestinal surgery patients immediately post-operatively. But the optimal level of protein supplementation required to maximise recovery in gastrointestinal surgery patients is effectively unknown, and may warrant further study.