Hemodynamic improvement using methylene blue after calcium channel blocker overdose

Abstract

Calcium channel blocker overdoses are often fatal despite standard treatment. Methylene blue is a novel adjunct that should be considered in refractory cases. Currently accepted therapeutic modalities include intravenous fl uids, calcium, vasopressors and high-dose insulin euglycemic therapy, however shock may persist despite these treatment options. [1] Methylene blue has been utilized in sepsis, shock after cardiac surgery and other non-poisoning causes of shock. However, there are only ten human case reports and one animal study regarding its utility. The case reports describe its use in shock caused by quetiapine, valsartan and dihydropyridine calcium channel blockers, and measure the outcomes of hemodynamics and mortality. The animal study used a rat-model with thirty subjects treated with a lethal dose of amlodipine, followed by methylene blue or normal saline. Results revealed an increase in heart rate, mean arterial pressure (MAP) and median survival time in those treated with methylene blue. [2] E x pe r t c o n s e n s u s r e c o m m e n d a t i o n s f o r t h e management of calcium channel blocker poisoning in adults were recently assembled and did not recommend the use of methylene blue as first-line treatment, given that the experience was limited to a small number of case reports. [1] However, with additional case reports attesting to its effi cacy, there may be a role for methylene blue in the treatment of drug-induced vasodilatory shock. We present a case where methylene blue was administered to a patient suffering from refractory vasodilatory shock following toxic ingestion of amlodipine, resulting in subsequent hemodynamic improvement.

Importance of early intervention in verapamil overdose – Case Report and antidotes review

“…However, it increased median survival time, mean arterial pressure and heart rate [55]. It was reported that methylene blue improves haemodynamic parameters in patients suffering from drug-induced refractory vasodilatory shock [56][57][58]. Administration of therapeutic doses, i.e.…”

Rapid reversal of vasoplegia with methylene blue in calcium channel blocker poisoning

“…MB does not affect the calcium channels or bypass it to increase intracellular cyclic adenosine mono phosphate (cAMP), rather, represents a clinical approach directed towards one of the underlying pathobiologies of vasoplegia in CCB overdose. Successful therapy with rapid improvement of hemodynamic status has been reported in a few cases [ 7 ]. CCBs upregulate endothelial nitric oxide synthase activity (eNOS) and increase the production of nitric oxide (NO) [ [8] , [9] ].…”

Methylene blue in the management of severe distributive shock in calcium channel blocker overdose

“…To our knowledge, currently, there are no randomized control trials to support its use in CCB overdose, and evidence is currently limited to observational studies in the form of single case reports. In 2019, Ahmed and Barnes reported similar benefits of methylene blue administration in the case of amlodipine overdose [14]. Pasin et al conducted a meta-analysis of randomized trials evaluating the efficacy of methylene blue on raising mean arterial pressure in distributive shock in ICU patients with sepsis, patients' post-cardiac and liver transplant surgery [15].…”