Validation of the Canadian Clinical Practice Guidelines for Nutrition Support in Mechanically Ventilated, Critically Ill Adult Patients: Results of a Prospective Observational Study

Objective: Recently, evidence-based clinical practice guidelines for the provision of nutrition support in the critical care setting have been developed. To validate these guidelines, we hypothesized that intensive care units whose practice, on average, was more consistent with the guidelines would have greater success in providing enteral nutrition.

Design: Prospective observational study.

Setting: Fifty-nine intensive care units across Canada.

Patients: Consecutive cohort of mechanically ventilated patients.

Interventions: In May 2003, participating intensive care units recorded nutrition support practices on a consecutive cohort of mechanically ventilated patients who stayed for a minimum of 72 hrs. Sites enrolled an average of 10.8 (range, 4-18) patients for a total of 638. Patients were observed for an average of 10.7 days.

Measurements And Main Results: We examined the association between five recommendations from the clinical practice guidelines most directly related to the provision of nutrition support (use of parenteral nutrition, feeding protocol, early enteral nutrition, small bowel feedings, and motility agents) and adequacy of enteral nutrition. We defined adequacy of enteral nutrition as the percent of prescribed calories that patients actually received. Across sites, the average adequacy of enteral nutrition over the observed stay in intensive care unit ranged from 1.8% to 76.6% (average 43.0%). Intensive care units with a greater than median utilization of parenteral nutrition (>17.5% patient days) had a much lower adequacy of enteral nutrition (32.9 vs. 52.7%, p < .0001). Intensive care units that used a feeding protocol tended to have a higher adequacy of enteral nutrition than those that did not (44.9 vs. 38.5%, p = .03). Intensive care units that initiated enteral nutrition on >50% of their patients within the first 48 hrs had a higher adequacy of enteral nutrition than those that did not (48.1 vs. 34.4%, p < .0001). Intensive care units that had a >50% utilization of motility agents and/or any small bowel feedings in patients with high gastric residuals tended to have a higher adequacy of enteral nutrition than those intensive care units that did not (45.6 vs. 39.2%, p = .04, and 48.4 vs. 41.8%, p = .16, respectively).

Conclusions: Intensive care units that were more consistent with the Canadian clinical practice guidelines were more likely to successfully feed patients via enteral nutrition. Adoption of the Canadian clinical practice guidelines should lead to improved nutrition support practice in intensive care units. This may translate into better outcomes for critically ill patients receiving nutrition support.