Poster 058: Methylene blue as adjuvant therapy in refractory vasoplegic shock: presentation of a clinical case

Background: Mortality rates from refractory septic shock can reach 60%. Methylene blue is thought to produce catecholamine-sparing effects through the pathophysiology of selectively blocking soluble guanylate cyclase and inhibiting nitric oxide synthase, which reduces its vasodilatory effects approximately 30 to 60 minutes after intravenous administration. Success story using methylene blue

Methods: A 43-year-old male with no comorbidities presented to the emergency department with acute abdominal pain. The surgical approach was LAPE + appendectomy, with discharge to the recovery room with a reservoir mask in poor condition in general with ventilatory deterioration requiring advanced airway management. He was admitted to the intensive care unit with poor progress, presenting distal cyanosis with capillary refill of 8 seconds, mottling 3 points. Lactate 4.4
mmol/L with SOFA score: 18 points, APACHE II 40 points, SAPS II 96 points, NUTRIC score 6 points, McMahon 11.5 points, in a state of refractory septic shock requiring management with shock-dose steroids, triple antimicrobial regimen. Given the hemodynamic deterioration and persistence of shock, vasopressors were sequentially initiated at doses of norepinephrine 0.62 mcg/kg/min, vasopressin 0.066 IU/min, and epinephrine 0.08 mcg/kg/min, without achieving maintenance of perfusional MAP. Due to the pathophysiology of refractory shock, it was decided to initiate rescue therapy and, as an adjunct, methylene blue at a dose of 2 mg/kg corresponding to 180 mg IV bolus. With subsequent hemodynamic improvement 8 hours after the first administration, vasopressors were withdrawn, with total withdrawal at 72 hours.

Outcome: Due to the pathophysiology of refractory shock, it was decided to initiate rescue therapy and, as an adjunct, methylene blue at a dose of 2 mg/kg corresponding to 180 mg IV bolus. With subsequent hemodynamic improvement 8 hours after the first administration, vasopressors were withdrawn, with total withdrawal at 72 hours. Despite the therapy implemented, he presented refractory metabolic acidosis with hyperlactatemia, anuria, KDIGO III acute kidney injury with electrolyte imbalance: hyperkalemia, hyperphosphatemia, hypocalcemia, requiring intermittent hemodialysis renal support therapy, presenting diuresis and decreased azotemia in his fourth session. On day 8, the ventilator was removed and the patient was extubated. The patient remained conscious with the ICU staff and stayed in the hospital for 25 days, without requiring vasopressors or renal replacement therapy. He was discharged to his home.

Conclusion: Methylene blue has been proposed as an adjuvant therapy in refractory septic shock due to its ability to inhibit nitric oxide synthesis and reverse pathological vasodilation. In this case, a single dose was associated with improvement in hemodynamic parameters and reduced vasopressor requirements, consistent with previous reports.