Effects of Polymyxin B Hemoperfusion on Septic Shock Patients Requiring Noradrenaline: Analysis of a Nationwide Administrative Database in Japan

Introduction: Polymyxin B hemoperfusion (PMX) reduces endotoxin in septic shock patients' blood and can improve hemodynamics and organ functions. However, its effects on the reduction of septic shock mortality are controversial. Methods: Using the Japanese diagnosis procedure combination database from April 2016 to March 2019, we identified adult septic shock patients treated with noradrenaline. This study used propensity score matching to compare the outcome between PMX-treated and non-treated patients. The primary endpoint was 28-day mortality, counting from the day of noradrenaline initiation. The secondary endpoints were noradrenaline-, ventilator-, and continuous hemodiafiltration (CHDF)-free days at day 28. Results: Of 30,731 eligible patients, 4,766 received PMX. Propensity score matching produced a matched cohort of 4,141 pairs with well-balanced patient backgrounds. The 28-day survival rate was 77.9% in the PMX group and 71.1% in the control group (p < 0.0001). Median days of noradrenalin-, CHDF-, and ventilator-free days were 2 days (p < 0.0001), 2 days (p < 0.0001), and 6 days (p < 0.0001) longer in the PMX group than in the control group, respectively. When stratified with the maximum daily dose of noradrenaline, the PMX group showed a statistically significant survival benefit in the groups with noradrenaline dose <20 mg/day but not in the noradrenaline group dose ≥20 mg/day. Conclusion: Analysis of large Japanese databases showed that septic shock patients who received noradrenaline might benefit from PMX treatment.