Tolerability and safety of enteral nutrition in critically ill patients receiving intravenous vasopressor therapy.

BACKGROUND: Enteral nutrition (EN) is recommended within the first 24-48 hours following admission to an intensive care unit (ICU) once resuscitation and hemodynamic stability have been achieved; however, hemodynamic stability is not well defined.
OBJECTIVE: To evaluate the tolerability and safety of EN in critically ill patients receiving intravenous (IV) vasopressor therapy.
METHODS: A retrospective medical record review was conducted in an urban academic medical center and included adult ICU patients from 2011 who received concomitant EN and IV vasopressor therapy for ≥1 hour. EN tolerance was defined as an absence of gastric residuals ≥300 mL, emesis, positive finding on abdominal imaging, and evidence of bowel ischemia/perforation.
RESULTS: Two hundred fifty-nine patients received 346 episodes of concomitant EN and IV vasopressor therapy. Overall EN tolerability was 74.9%. Adverse events included rising serum lactate (30.6%), elevated gastric residuals (14.5%), emesis (9.0%), positive finding on kidney/ureter/bladder radiograph (4.3%), and bowel ischemia/perforation (0.9%). An inverse relationship was found between maximum norepinephrine equivalent dose and EN tolerability (12.5 mcg/min for patients who tolerated EN vs 19.4 mcg/min, P = .0009). This relationship remained statistically significant after controlling for other variables (P = .019). Patients who tolerated EN were less likely to have received dopamine (63.8% vs 77.6%, P = .018) or vasopressin (58.9% vs 77.9%, P = .0027). These patients received concomitant therapy for less time and received more nutrition.
CONCLUSIONS: Most patients receiving IV vasopressor therapy tolerate EN. Tolerability was related to the maximum cumulative vasopressor dose and may be related to the specific vasopressor administered.