Contradictory Findings of Two Recent Meta-Analyses: What Are We Supposed to Believe About Anesthetic Technique in Patients Undergoing Cardiac Surgery?

Abstract

Contradictory findings of two recent meta-analyses: what are we supposed to believe about anesthetic technique in patients undergoing cardiac surgery?,

Volatile Anaesthesia versus Total Intravenous Anaesthesia for Cardiac Surgery—A Narrative Review

“…After a period of myocardial ischaemia of variable duration, further reperfusion may lead to additional injury beyond that generated by the ischemia and may manifest as arrhythmias, reversible contractile dysfunction (myocardial stunning), endothelial dysfunction and ultimately irreversible injury with myocardial cell death [ 1 , 11 ]. The magnitude of myocardial ischaemia is highly variable and depends upon the severity of the underlying disease, the duration of aortic cross-clamping, and the quality of myocardial protection during CPB [ 12 ]. Myocardial injury can result in delayed recovery, organ failure, increased hospital LOS, and mortality.…”

“…Although the authors speculated on the role of propofol in increased mortality, analysis of the subgroups with and without any propofol administration throughout all anaesthesia time showed only a trend in the reduction of mortality in those not receiving propofol. Moreover, the study has been criticised for the high rate of lost to follow up and a substantial difference in 1-year mortalities, especially in the propofol group, as compared to other studies, which might influence the results [ 12 , 54 ]. These discussions indicate that long-term mortality might be influenced by factors other than anaesthesia and surgery.…”

“…It is worth noting that the MYRIAD trial accounted for 57% of included patients. However, this meta-analysis has been criticised for including only 71% (618 of 868) of the patients from one trial [ 40 ] for reasons that are not explained [ 12 ].…”

“…anaesthetics were used for some period in the VA group, which may have attenuated the favourable effect. Noteworthy, this meta-analysis was criticised for excluding patients who underwent OPCAB (almost 2000 patients), which also meant that only a sub-cohort of those included in the MYRIAD trial were analysed, which was considered to result in an unacceptable risk of bias [ 12 ].…”

“…Intriguingly, the 2 meta-analyses discussed above [ 66 , 67 ] included slightly different studies, which may explain the contradictory conclusions [ 12 ]. Moreover, neither one included an old RCT by Slogoff and Keats [ 68 ], which showed that outcomes of patients undergoing cardiac surgery were similar when VA were compared with a TIVA (benzodiazepine and sufentanil) and pointed out the role of the anaesthesia management in the rate of perioperative complications.…”