Variability in Perioperative Fasting Practices Negatively Impacts Nutritional Support of Critically Ill Intubated Patients

Abstract

The aim of the study was to quantify nutritional losses related to pre- and postoperative fasts in critically ill intubated patients and to explore whether shorter fasts are safe and appropriate in this population. A retrospective review of mechanically ventilated adults undergoing surgery more than 24 hours after admission to a Level I trauma center over 15 months was done, which yielded 132 procedures and 81 unique patients. Ninety per cent of preoperative periods and 43 per cent of postoperative periods were affected by nonmedical barriers to feeding. Eighty-two per cent of gastrically fed nonemergent cases were fasted for longer than the 6-hour American Society of Anesthesiologists guideline, whereas 91 per cent of emergent cases had shorter fasts. There were no anesthetic complications, placing an upper limit of 6 per cent on the rate of aspiration for fasts shorter than six hours (95% confidence). Forty-three per cent of cases did not resume tube feeds within 90 minutes postoperatively, and only 37 per cent had a documented justification for delay. Intubated patients were frequently fasted preoperatively for longer than recommended and postoperatively for longer than medically indicated. No complications were observed with shorter-than-guideline fasts. This strengthens the evidence that “standard” preoperative fasting is unnecessary and deleterious in many critically ill intubated patients. New protocols and national guidelines are needed to ensure adequate nutrition.