The following article is one of two articles offered for continuing education credit in this issue. Please see page 382 for details. Canadian Clinical Practice Guidelines for Nutrition Support in Mechanically Ventilated, Critically Ill Adult Patients

Objective: This study was conducted to develop evidence-based clinical practice guidelines for nutrition sup- port (ie, enteral and parenteral nutrition) in mechanically ventilated critically ill adults. Options: The following inter- ventions were systematically reviewed for inclusion in the guidelines: enteral nutrition (EN) versus parenteral nutri- tion (PN), early versus late EN, dose of EN, composition of EN (protein, carbohydrates, lipids, immune-enhancing addi- tives), strategies to optimize delivery of EN and minimize risks (ie, rate of advancement, checking residuals, use of bedside algorithms, motility agents, small bowel versus gas- tric feedings, elevation of the head of the bed, closed delivery systems, probiotics, bolus administration), enteral nutrition in combination with supplemental PN, use of PN versus standard care in patients with an intact gastrointestinal tract, dose of PN and composition of PN (protein, carbohy- drates, IV lipids, additives, vitamins, trace elements, immune enhancing substances), and the use of intensive insulin therapy. Outcomes: The outcomes considered were mortality (intensive care unit (ICU), hospital, and long- term), length of stay (ICU and hospital), quality of life, and specific complications. Evidence: We systematically searched MEDLINE and CINAHL (cumulative index to nursing and allied health), EMBASE, and the Cochrane Library for ran- domized controlled trials and meta-analyses of randomized controlled trials that evaluated any form of nutrition support in critically ill adults. We also searched reference lists and personal files, considering all articles published or unpub- lished available by August 2002. Each included study was critically appraised in duplicate using a standard scoring system. Values: For each intervention, we considered the validity of the randomized trials or meta-analyses, the effect size and its associated confidence intervals, the homogeneity of trial results, safety, feasibility, and the economic conse- quences. The context for discussion was mechanically venti- lated patients in Canadian ICUs. Benefits, Harms, and Costs: The major potential benefit from implementing these guide- lines is improved clinical outcomes of critically ill patients (reduced mortality and ICU stay). Potential harms of imple- menting these guidelines include increased complications and costs related to the suggested interventions. Summaries of Evidence and Recommendations: When considering nutrition support in critically ill patients, we strongly recommend that EN be used in preference to PN. We recommend the use of a standard, polymeric enteral formula that is initiated within 24 to 48 hours after admission to ICU, that patients be cared for in the semirecumbent position, and that arginine-contain- ing enteral products not be used. Strategies to optimize deliv- ery of EN (starting at the target rate, use of a feeding protocol using a higher threshold of gastric residuals volumes, use of motility agents, and use of small bowel feeding) and mini- mize the risks of EN (elevation of the head of the bed) should be considered. Use of products with fish oils, borage oils, and