Protocol for a Randomized, Open-Label, Multicenter, Parallel-Controlled Study Evaluating Modified Double Filtration Plasmapheresis for the Treatment of Septic Shock.

Septic shock (SS) is defined as sepsis-induced hypotension persisting despite adequate fluid resuscitation. Modified double filtration plasmapheresis (M-DFPP) is a promising therapeutic approach designed to selectively remove small-to-medium molecular weight inflammatory mediators while preserving essential plasma proteins, potentially restoring immune balance and stabilizing hemodynamics in patients with SS. Eligible patients diagnosed with SS will be enrolled in this randomized controlled trial. Inclusion criteria include completion of early goal-directed therapy resuscitation standards within 12 h following admission to the intensive care unit and norepinephrine administration exceeding 0.5 µg/min/kg. The intervention group will receive treatment using the M-DFPP multivariate model. The primary endpoint is all-cause mortality at 28 days. Secondary endpoints will assess the efficacy of M-DFPP in reducing inflammatory mediators, evaluate changes in vasoactive drug requirements on the third day post-enrollment, and quantify improvement in organ dysfunction. Validation through well-designed, large-scale randomized controlled trials is required to clarify the optimal patient selection criteria, treatment timing, frequency, and standardized protocols for M-DFPP. This is an experimental protocol of a randomized, open-label, multicenter, parallel-controlled trial aiming to evaluate whether M-DFPP can improve survival rates in patients with SS.