A Pilot Study on Continuous Infusion of 4% Albumin in Critically Ill Patients: Impact on Nosocomial Infection via a Reduction Mechanism for Oxidized Substrates

Abstract

Objective: Care-related infections affect up to 11% of ICU patients. Running therapeutic albumin is sometimes associated to less infection: whether a specific method of its infusion is of any interest to modulate innate defense is unknown. Our objectives were: 1) to test whether the method for albumin infusion is important to prevent care-related infections and 2) to analyze in vitro the antioxidative role of albumin on host defense proteins during shock (using vasostatin-I as an example). Design: In a prospective, randomized, open-label trial, shock patients were allocated to receive either continuously 4% albumin or intermittently 20% albumin, as long as they were infused with norepinephrine. A translational study including in vivo and in vitro analyses of albumin-vasostatin-I interactions is reported. Setting: A tertiary ICU caring for 1,000 patients per year. Patients: Fifty shock patients with serum albumin less than 20 g/L. Interventions: In vivo colonization and nosocomial infections were recorded and time-dependent changes in serum albumin, chromogranin A, and vasostatin-I concentrations as well. In vitro, we studied biochemical albumin-vasostatin-I relationship using biochemical methods. Measurements and Main Results: Over 18 days, we recorded a decrease in colonization (four vs 12 episodes; p = 0.035) and nosocomial infection frequency (two vs 13 episodes; p = 0.002) in patients infused continuously 4% albumin versus controls. In vitro, albumin interacts with the disulfide loop vasostatin-I (residues 17-40) and continuous 4% albumin infusion restores its oxidative status required for antimicrobial activity. Conclusions: Continuous 4% albumin is effective in reducing care-related infections in shock patients by increasing the availability of antimicrobial vasostatin-I. This might guide future care of shock patients.