Propranolol attenuates factors affecting hypermetabolism in pediatric burn patients

Background

The aim of this study was to determine the effect of propranolol on infections and clinical parameters during the acute phase postburn. Severe thermal injury is followed by a period of hypermetabolism that is directly proportional to the size of insult sustained. Infection and multiorgan failure are now the leading cause of death from severe thermal injuries. Propranolol, an anticatabolic agent, improves hypermetabolism postburn. However, there is evidence that propranolol worsens immune function and increases the incidence of infection in critically ill patients.

Methods

Sixty-six patients with burns >40% total body surface area were enrolled into the study and randomized to receive standard burn care (controls, n = 33) or standard burn plus propranolol for more than 21 days (propranolol, 0.5–1.5 mg/kg every 6 hours, n = 33). Biopsies were taken three times a week for microbiological determination. Clinical parameters were collected and blood was drawn at regular intervals throughout the hospital course and analyzed for IGF-1, IGFBP-3, and HGH. Patients underwent weekly resting energy-expenditure measurements. Statistical analysis was performed using analysis of variance with Bonferoni's correction and Student's t test where applicable.

Results

Propranolol treatment reduced heart rates by 10% and significantly improved stroke volume throughout the acute hospital stay compared with controls (P < 0.05). Resting energy expenditure was significantly decreased in the propranolol group when compared with controls at discharge (P < 0.05). Infection rates on admission were the same for both groups (17% propranolol vs 22% control). The incidence of infection throughout hospital course was significantly lower in the propranolol group (60%) compared with controls (87%) (P < 0.05). Propranolol significantly increased IGF-I, IGFBP-3, GH, and prealbumin, while it significantly decreased CRP and fatty acids (P < 0.05).

Conclusion

Following a severe burn, propranolol attenuates infections, inflammatory markers and fatty acid levels while improving cardiac work and endogenous anabolic hormone levels. We suggest that propranolol is a safe and efficacious modulator of the postburn response.