Randomization, intervention and measurements
ARDS, septic shock
ARDS, ACUTE RESPIRATORY DISTRESS SYNDROME, SEPTIC SHOCK
After signing informed consent, patients were randomly assigned to receive MB using a predetermined randomization sequence prepared in sealed opaque envelopes. The sequence was generated by computer with a 1:1 allocation ratio, using permuted blocks with a size of 4. Critical care physicians were responsible for assignment of intervention. Patients, clinicians, investigators and outcome assessors were blinded to the treatment received.Patients assigned to MB group received an intravenous (IV) infusion of 100 mg of MB in 500 ml of 0.9% sodium chloride solution over 6 h once daily for a total of 3 doses. Patients assigned to control group received the same dose of 500 ml of 0.9% sodium chloride without MB. In order to avoid visual identification of the infusion, all infusion bags and polyvinylchloride lines were prepared at central pharmacy with opaque envelopes.In our unit, fluid resuscitation of septic shock is guided by dynamic tests for prediction of volume responsiveness before any IV fluid load; the most common methods in order of frequency are aortic velocity–time integral change after passive leg raising (cut-off 10%), arterial pulse pressure variation (cut-off 13%), tidal volume challenge (cut-off 3.5%), and respiratory variation of carotid peak flow velocity (cut-off 14%) [In patients of both groups, adjunctive vasopressin was initiated at a dose of 0.03 IU/min if norepinephrine dose reached ≥ 0.25 mcg/kg/min; evaluation of volume responsiveness was repeated at least 3 times each day as long as vasopressors were needed. Hydrocortisone at 200 mg/day dose by continuous infusion is also a standard in our unit, and it is withheld within 6-h after discontinuation of all vasopressors without taper [Recorded information at randomization included demographic, ventilatory and laboratory data, including diagnosis of acute respiratory distress syndrome (ARDS) defined according to Berlin criteria [