Twenty years of vasoplegic syndrome treatment in heart surgery. Methylene blue revised.

Abstract

OBJECTIVE:

This study was conducted to reassess the concepts established over the past 20 years, in particular in the last 5 years, about the use of methylene blue in the treatment of vasoplegic syndrome in cardiac surgery.

METHODS:

A wide literature review was carried out using the data extracted from: MEDLINE, SCOPUS and ISI WEB OF SCIENCE.

RESULTS:

The reassessed and reaffirmed concepts were 1) MB is safe in the recommended doses (the lethal dose is 40 mg/kg); 2) MB does not cause endothelial dysfunction; 3) The MB effect appears in cases of NO up-regulation; 4) MB is not a vasoconstrictor, by blocking the cGMP pathway it releases the cAMP pathway, facilitating the norepinephrine vasoconstrictor effect; 5) The most used dosage is 2 mg/kg as IV bolus, followed by the same continuous infusion because plasma concentrations sharply decrease in the first 40 minutes; and 6) There is a possible "window of opportunity" for MB's effectiveness. In the last five years, major challenges were: 1) Observations about side effects; 2) The need for prophylactic and therapeutic guidelines, and; 3) The need for the establishment of the MB therapeutic window in humans.

CONCLUSION:

MB action to treat vasoplegic syndrome is time-dependent. Therefore, the great challenge is the need, for the establishment the MB therapeutic window in humans. This would be the first step towards a systematic guideline to be followed by possible multicenter studies.

• Authors: Paulo Roberto Barbosa Evora, Lafaiete Alves Junior, Cesar Augusto Ferreira, Antônio Carlos Menardi, Solange Bassetto, Alfredo José Rodrigues, Adilson Scorzoni Filho, Walter Vilella de Andrade Vicente
• Journal: Revista brasileira de cirurgia cardiovascular : orgao oficial da Sociedade Brasileira de Cirurgia Cardiovascular (Rev Bras Cir Cardiovasc) 2015 Jan-Mar Vol. 30 Issue 1 Pg. 84-92 Brazil
• PMID: 25859872 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Review)

Chemical References

• Enzyme Inhibitors
• Methylene Blue

Topics

• Cardiac Surgical Procedures (adverse effects)
• Enzyme Inhibitors (therapeutic use)
• Humans
• Methylene Blue (therapeutic use)
• Risk Factors
• Time Factors
• Treatment Outcome
• Vasoplegia (drug therapy)