Use of methylene blue in the treatment of refractory vasodilatory shock after cardiac assist device implantation: report of four consecutive cases

Effect of methylene blue on hemodynamic response in the early phase of septic shock: A case series

RATIONALE

Methylene blue (MB) has been used to increase blood pressure in septic shock, acting on the activity of guanylate cyclase and nitric oxide synthase.

PATIENCE CONCERNS

The aim of this study is to demonstrate the benefit of MB in early phase of septic shock.Diagnoses: We report 6 cases of patients with septic shock with up to 72 hours of evolution.

INTERVENTIONS

We used MB after fluid replacement, use of norepinephrine and vasopressin. Patients received a loading dose of MB and maintenance for 48 hours.

OUTCOMES

All patients presented a reduction in the dose of vasopressors and lactate levels soon after the administration of the loading dose of MB, an effect that was maintained with the maintenance dose for 48 hours. Interleukin 6 and interleukin 8 were elevated at the beginning of the septic condition, with a progressive and marked reduction after the beginning of MB infusion, demonstrating a role of MB in reducing the inflammatory activity.

LESSONS

This case series suggests that MB used early in the treatment of septic shock may be useful in reducing vasopressor dose and lactate levels. Further studies are still required to further validate these findings.

Methylene Blue for Vasoplegic Syndrome After Cardiac Operation: Early Administration Improves Survival

BACKGROUND

Vasoplegic syndrome, defined by hypotension despite normal or increased cardiac output, is associated with high mortality rate after cardiopulmonary bypass. Methylene blue (MB) is reported to ameliorate vasoplegic syndrome through the nitric oxide pathway. We hypothesized that early administration of MB would improve outcomes in patients with vasoplegic syndrome after cardiopulmonary bypass.

METHODS

All patients that underwent cardiopulmonary bypass at our institution (Jan 1, 2011 to Jun 30, 2016) were identified through our Society of Thoracic Surgery database. Pharmacy records identified patients receiving MB within 72 hours of cardiopulmonary bypass. Multivariate logistic regression identified predictors of major adverse events among patients receiving MB.

RESULTS

A total of 118 cardiopulmonary bypass patients (3.3%) received MB for vasoplegic syndrome. These patients had a higher incidence of comorbidities, and these cases were more commonly reoperative (76.1% versus 41.2%, p < 0.0001) and complex (70.3% versus 31.8%, p < 0.0001). The only difference in preoperative medications was that MB patients had a higher rate of amiodarone use (15.3% versus 2.2%, p < 0.0001). MB patients had significantly higher rates of postoperative complications, except atrial fibrillation. Early (operating room, 40.7%) versus late (intensive care unit, 59.3%) administration of MB was associated with significantly reduced operative mortality rate (10.4% versus 28.6%, p = 0.018) and risk-adjusted major adverse events (odd ratio 0.35, p = 0.037).

CONCLUSIONS

Operative mortality rate is high in patients receiving MB for the treatment of vasoplegia after cardiopulmonary bypass. Early administration of MB improves survival and reduces the risk-adjusted rate of major adverse events in these patients.

Methylene blue reverses recalcitrant shock in β-blocker and calcium channel blocker overdose

β-blocker and calcium channel blocker toxicity generally present with bradycardia and hypotension. A 69-year-old woman presented after a suicide attempt with a β-blocker and calcium channel blocker overdose. Her blood pressure was 69/35 mm Hg and her HR was in the 40s. She was treated with calcium chloride, glucagon, a dextrose-insulin infusion and three vasopressors, but remained hypotensive. She suffered two cardiac arrests and required a transvenous pacemaker. When all interventions failed, she was started on a methylene blue infusion for refractory vasodilatory shock which resulted in a dramatic improvement in her blood pressure. The patient was successfully weaned off all vasopressors and from mechanical ventilation without any end-organ damage.