Aim: To assess the acute effects of methylene blue infusion, an inhibitor of nitric oxide synthesis, on hemodynamic parameters in patients with refractory septic shock.
Patients and methods: Fourteen patients admitted to intensive care units with septic shock of diverse etiologies and unable to maintain median arterial pressures over 60 mm Hg with the use of at least 2 vasoactive drugs, were studied. All received a 1 mg/kg bolus of methylene blue Hemodynamic parameters were measured before and 30, 60, 120 and 180 min after the bolus.
Results: Systolic and diastolic blood pressure and systemic vascular resistance increased in all patients. There were no significant changes in cardiac output, oxygen consumption or extraction.
Conclusions: Methylene blue has an acute pressor effect in patients with septic shock.