Fasting practices of enteral nutrition delivery for airway procedures in critically ill adult patients: A scoping review

BACKGROUND

There is limited understanding of fasting practices and reported safety concerns for airway procedures in critically ill adults.

OBJECTIVE

To describe fasting practices including safety concerns for airway procedures in critically ill adult patients in the reported literature.

INCLUSION CRITERIA

Studies conducted in adult critically ill patients receiving enteral nutrition (EN) and undergoing an airway procedure (endotracheal intubation, endotracheal extubation, and tracheostomy) were included if EN fasting practices and/or prespecified nutrition and clinical outcomes were reported.

METHODS

A scoping review using the Joanna Briggs Institute methodology was conducted. MEDLINE, Embase, and CINAHL were searched from 2000 to January 19, 2022. Results are presented via narrative synthesis.

RESULTS

Fourteen studies were included, with only one randomised control trial (RCT). Twelve studies reported on fasting practices with varied EN fasting durations (0-34 h) and two reported data on nutrition adequacy. Three studies investigated continued EN in one study arm and four studies minimised fasting duration by including gastric suctioning prior to the airway procedure. Safety concerns primarily related to aspiration events (61%) were reported in nine studies.

CONCLUSION

In the reported literature, there is wide variation in EN fasting practices for airway procedures in critically ill patients with limited evidence to inform practice.

How long are mechanically ventilated patients fasted prior to surgery? An exploratory study examining preoperative fasting practices across trauma centres

For mechanically ventilated patients undergoing surgery, interrupting enteral feeding to prevent pulmonary aspiration is common; however, there are no published preoperative fasting guidelines for these patients, resulting in fasting practices that often vary greatly between hospitals. This retrospective study described fasting practices and surgical outcomes of mechanically ventilated patients across five trauma centres. The primary exposure was hours nil per os before surgery and was stratified into short (<6h) and moderate (≥6h) fasting duration. Shared frailty models assessed the relationship between time to perioperative complication and nil per os category. Three of the five hospitals had preoperative fasting guidelines, and those most compliant required patients to be fed up until surgery. Most patients were fasted ≥6h prior to surgery and no increased risk of complication was found for patients who were fasted <6h. Future studies are needed to establish appropriate preoperative fasting thresholds for mechanically ventilated patients.