Earlier Application of Methylene Blue in Vasoplegic, Adrenergic Vasopressor-Resistant Patients is Associated with Better Clinical Outcomes. A Retrospective Analysis of 464 Patients

Background. Severe shock, characterized by profound and refractory hypotension, hails a dismal prognosis for patients in intensive care units. Management typically involves fluid resuscitation and vasopressor support. Vasoplegic patients, refractory to adrenergic catecholamines face an increased risk for in-hospital mortality. However, the optimal timing for Methylene Blue (MB) in these vasopressor-resistant patients, remains unclear. Methods. This was a retrospective, single-center study conducted in the intensive care unit (ICU) of a tertiary medical center. Patients included in the analysis were suffering from vasoplegia and received MB at some point during their hospitalization. Results. A total of 464 patients were included, with (183 (39%) in the general ICU and 281 (61%) in the cardiothoracic ICU. All patients developed vasoplegia and were treated with MB following a median time of 11.2 hours. Earlier (< 11.2 hours) MB administration was associated with significantly improved clinical outcomes including lower ICU mortality (30% vs. 52%, p  < 0.001); reduced in-hospital mortality (41% vs. 59%, p  < 0.001) and decreased need for continuous venous-venous hemofiltration (CVVH) (33% vs. 53%, p  < 0.001). Earlier MB administration was associated with a 36% in-hospital mortality risk reduction in a univariate analysis (HR = 0.64; CI 95% 0.47–0.86, p = 0.003) and remained statistically significant in a multivariate analysis, reducing the risk for in-hospital mortality in 31% (HR = 0.69; CI 95% 0.51–0.94, p = 0.018). Conclusions. Early administration of MB to ICU patients with vasoplegia may be associated with significantly improved clinical outcomes. Future prospective studies are warranted to evaluate the incorporation of earlier MB administration into relevant treatment protocols.