MortalitY in caRdIAc surgery (MYRIAD): A randomizeD controlled trial of volatile anesthetics. Rationale and design

Abstract

The trial will determine whether the simple intervention of adding a volatile anesthetic, an intervention that can be implemented by all anesthesiologists, can improve one-year survival in patients undergoing coronary artery bypass graft surgery.

Volatile Anesthetics versus Total Intravenous Anesthesia for Cardiac Surgery

“…Interim analyses were planned after enrollment of 25%, 50%, and 75% of the planned number of patients. 23,32,33 The planned approach to statistical analysis was published previously. 23 Primary analyses were performed according to the intention-to-treat principle.…”

“…Details of the rationale, design, and statistical plan have been published previously. 23 The MYRIAD trial was endorsed by the European Association of Cardiothoracic Anesthesiologists and was funded by the Italian Ministry of Health. The funding body had no role in the design of the trial, the collection and analysis of the data, or the writing of the manuscript or in the decision to submit the manuscript for publication.…”

“…Several strategies to enhance the cardioprotective effect of volatile anesthetics have been proposed. 8,23,24 We recommended but did not require implementation of the following three specific strategies: maintenance of at least 1.0 minimum alveolar concentration of the volatile anesthetic (which represents an anesthetic maintenance dose with documented clinical and preconditioning effects) for at least 30 minutes; discontinuation of the volatile agent at least 15 minutes before cardiopulmonary bypass; and at least three wash-in and wash-out periods, which were defined by administration of at least 0.5 minimum alveolar concentration of the volatile agent for 10 minutes interspersed by a wash-out period of 10 minutes or more.…”

The Impact of Anesthetic Regimen on Outcomes in Adult Cardiac Surgery: A Narrative Review

“…Several factors may have contributed to these results, including an actual low incidence of severe perioperative myocardial ischemia in the current clinical practice of cardiac surgery, and, although the MYRIAD study clearly has shown that volatile anesthetics are not a magic bullet, its findings probably did not allow for the definite exclusion of any beneficial effect of volatile anesthetics in cardiac surgery. 103 The pragmatic design of the MYRIAD study 55,104 left the attending anesthesiologist free to choose the volatile anesthetic to use, its doses and duration of administration, the phases of surgery in which to administer it, and whether simultaneously to use any intravenous agent (eg, opioids, propofol, midazolam). However, APC may be dose dependent and related to the timing and duration of administration and may be more pronounced with some agents over others, although the largest direct comparison between 2 different volatile anesthetics 105 and the aforementioned Bayesian network meta-analysis 95 did not suggest a different effect on clinically relevant outcomes among different volatile anesthetics; further, other drugs may enhance (eg, opioids) or counteract (eg, propofol) the cardioprotective action of volatile anesthetics (see Table 2).…”

Guidelines for enhanced recovery after cardiac surgery. Consensus document of Spanish Societies of Anesthesia (SEDAR), Cardiovascular Surgery (SECCE) and Perfusionists (AEP)

“…Los anestésicos volátiles o inhalatorios, frente al propofol, han demostrado preservar mejor la función cardiaca tras la CEC (menor liberación de troponinas), asociarse a menor mortalidad y a menos complicaciones pulmonares [216][217][218][219] . Sin embargo, el ensayo MYRIAD concluye que no existe una reducción significativa de la mortalidad a los 30 días ni al año en pacientes sometidos a cirugía electiva de revascularización coronaria 220 . Por ello, varias guías clínicas sugieren que esos resultados deberían aplicarse a la anestesia cardiaca 74,221 .…”