Efficacy of methylene blue in refractory septic shock: study protocol for a multicenter, randomized, placebo-controlled trial.

Background: Septic shock is now the leading cause of mortality in intensive care units (ICUs). Refractory septic shock requires high doses of vasopressors. Some previous studies have revealed that methylene blue could improve hypotension status and help reduce the dosage of catecholamines. This study aims to investigate the clinical effect of methylene blue in septic shock and explore whether it can increase arterial pressure and reduce the usage of vasopressors.

Methods: This study is a multicenter, randomized, placebo-controlled trial planning to include 100 refractory septic shock patients. The protocol is to administer a bolus of 2 mg/kg methylene blue intravenously followed by a continuous infusion of 0.5 mg/kg/h for 48 h. The primary outcome is the total dose of vasopressor required in refractory septic shock in the first 48 h. Secondary outcomes include other hemodynamic parameters, oxygen metabolism indexes, tissue perfusion indexes, major organ function indexes, and certain plasma cytokines and other factors.

Discussion: This protocol aims to evaluate the safety and efficacy of methylene blue as adjuvant therapy for refractory septic shock. The main outcome measure will be vasopressor requirements and hemodynamic parameters. Additionally, bedside ultrasonography, blood gases, and cytokines will be assessed to evaluate perfusion, respiratory, and metabolic effects. The results are intended to provide evidence on the safety and efficacy of methylene blue in refractory septic shock, guiding clinical decision-making.

Trial Registration: This clinical trial has been registered at ChiCTR ( https://www.chictr.org.cn/ ) on March 16, 2023. ChiCTR registration number: ChiCTR2300069430.