RESUMEN
As an inhibitor of nitric oxide, methylene blue has been investigated as an alternative vasopressor in patients with septic shock refractory to catecholamine vasopressors and as an agent to maintain hemodynamic stability in patients receiving intermittent hemodialysis. However, to our knowledge, the use of methylene blue as a vasopressor in patents receiving continuous renal replacement therapy has not been evaluated. We describe a 56-year-old man who was receiving continuous venovenous hemodiafiltration (CVVHDF) for acute renal failure secondary to sepsis. After a difficult hospital stay for injuries sustained from a motor vehicle accident, the patient developed sepsis and subsequent renal failure. On hospital day 47, after an adequate course of antibiotics, the patient developed refractory shock while receiving norepinephrine, phenylephrine, vasopressin, and hydrocortisone. He was then given a continuous infusion of methylene blue, which increased his mean arterial pressure and allowed for weaning of the catecholamine vasopressors. Eight hours after the start of methylene blue, the CVVHDF filter failed, and the hemodiafiltration was stopped. Because the filter was blue, a sample of the patient's effluent was analyzed by using ultraviolet-visible spectroscopy. No methylene blue was detected in the sample, suggesting that the drug was not being removed by CVVHDF. Clinicians should use caution when they are considering the use of methylene blue in patients with refractory shock who are also receiving CVVHDF.
