Efficacy of Human Albumin in Prevention of Intradialytic Hypotension in Critically Ill Patients with Hypoalbuminemia Undergoing Haemodialysis – A Randomized Controlled Trial

INTRODUCTION: Haemodialysis (HD) accounts for 89% of renal replacement therapy worldwide, making it the most common type.(1,2) Intradialytic hypotension (IDH) is one of the major complications of HD which is observed in 15% to 50% of patients.(3) IDH is defined as systolic blood pressure (SBP) or mean arterial pressure (MAP) reductions of 20 mm and 10 mm Hg respectively, based on National Kidney Foundation Kidney Disease Outcomes Quality Initiative Guidelines. This may or may not be accompanied by symptoms.(4) One of the independent associations of IDH is hypoalbuminemia due to the role of albumin in maintaining oncotic pressure. In hypoalbuminemic patients, decreased oncotic pressure leads to hypovolemia, which results in reduced plasma refill during haemodialysis leading to IDH.(5) There are a few studies regarding the prevention of IDH using plasma expanders. Only one study has been done with albumin(6), but the role of albumin in prevention of IDH still remains unexplored. OBJECTIVES: The primary objective was to evaluate the efficacy of human albumin in preventing intradialytic hypotension in critically ill patients with hypoalbuminemia undergoing haemodialysis. The secondary objectives were to compare the fluid removal and vasopressor requirement between two groups. MATERIALS AND METHODS: An open label parallel group randomized trial was designed in critically ill patients with hypoalbuminemia undergoing haemodialysis. Two hundred and five sessions of HD included. Haemodialysis sessions were randomized to either receive standard of care or 100 mL 20% human albumin at the initiation of haemodialysis along with standard of care. Patients' vital signs, fluid removed, ultrafiltration removal rate and blood flow rate were recorded every 15 minutes during HD. Vasopressor(s) requirement and dose was also noted. IDH was assessed as per the National Kidney Foundation Kidney Disease Outcomes Quality Initiative Guidelines. Any adverse events during or after the administration of 20% human albumin were also recorded. RESULTS: During the study period, 205 sessions of haemodialysis in 78 patients were included. The incidence of intradialytic hypotension was: [a] 51.5% with albumin vs 42.2% with standard of care group, (p = 0.182: as per the SBP fall of 20 mm Hg); [b] 64.1% with albumin vs 56.9% with standard of care group, (p = 0.291: as per the MAP fall of 10 mm Hg). The vasopressor requirement in the form of vasopressor addition/dose increase was 7.8% in albumin vs 28.4% in control group (p < 0.001). The mean fluid removed at the end of 4 hours: 2132.32 (±1217.32) mL with albumin vs 2240.88 (±941.80) mL with standard of care group (p = 0.619). CONCLUSION: The incidence of intradialytic hypotension was not significantly decreased in the intervention group. There was also no significant difference in fluid removal between two groups at the end of 4 hours though the vasopressor requirement was significantly higher in the control group. Among critically ill patients with hypoalbuminemia undergoing HD, albumin administration at the initiation of HD doesn't have a role in preventing intradialytic hypotension. However, albumin administration is beneficial in reducing the need of vasopressor(s) during HD, though it didn't affect total fluid removal.