Early enteral nutrition in patients with hemodynamic failure following cardiac surgery

Enteral nutrition (EN) is controversial in patients with circulatory compromise. This study assesses the feasibility and safety of EN given early after cardiac surgery in patients with hemodynamic failure.

Prospective observational study conducted in a surgical intensive care unit (ICU) of a tertiary hospital over 17 months.

Cardiac surgery patients with hemodynamic failure (dependence on 2 or more vasoactive drugs and/or mechanical circulatory support) requiring more than 24 hours of mechanical ventilation. Variables Examined: Descriptive data, daily hemodynamic data, and variables related to the efficacy and safety of EN. EN was performed according to our EN protocol.

Of 642 patients admitted to the ICU, 37 (5.8%) met the inclusion criteria. Of these, 11 (29.7%) required mechanical circulatory support, and 25 (68.0%) met the criteria for early multiorgan dysfunction. Mortality was 13.5%. Mean EN duration was 12.3 days (95% confidence interval [CI], 9.6-15.0). The mean EN diet volume delivered/patient/d was 1199 mL (95% CI, 1118.7-1278.8), and mean EN energy delivered/patient/d was 1228.4 kcal (95% CI, 1145.8-1311). The set energy target was achieved in 15 patients (40.4%). The most common EN-related complication was constipation. No case of mesenteric ischemia was detected.

Our findings indicate that early EN is feasible in this type of patients and not associated with serious complications. However, it is difficult to attain an appropriate energy target by EN alone. These observations point to a need for monitoring of daily energy delivery and balance, as well as careful monitoring of warning signs of intestinal ischemia.