The Effect of Isoflurane on Survival and Myocardial Infarction: A Meta-analysis of Randomized Controlled Studies
Journal of Cardiothoracic and Vascular Anesthesia, 07/25/2012
Evidence Based Medicine
Bignami E et al. – Isoflurane reduced mortality in high–quality studies and showed a trend toward a reduction in mortality when it was compared with propofol. No differences in the rates of overall mortality and myocardial infarction were noted.Methods
- Pertinent studies were searched independently in Biomed, Central, PubMed, Embase, and the Cochrane Central Register of clinical trials.
- The primary endpoint was mortality at the longest follow–up available.
- A meta–analysis of 37 trials.
- The 37 included trials randomized 3,539 patients in cardiac (16 studies) and in noncardiac surgery (21 studies) with noninhalation comparators in 55% of trials.
- The overall analysis showed no difference in mortality between the isoflurane and control groups (16/1,602 [1.0%] v 23/1,937 [1.2%], odds ratios (OR)=0.76 [0.39–1.47], p=0.4 with 37 studies included) and no difference in the rate of myocardial infarction (3/1,312 [0.2%] v 1/1,532 [0.07%], OR=2.03 [0.27–15.49], p=0.5 with 30 studies included).
- Mortality was reduced in the isoflurane group when only studies with a low risk of bias were included in the analyses (0/540 [0%] v 5/703 [0.7%] in the control arm, OR=0.13 [0.02–0.76], p=0.02) with 4 cardiac and 6 noncardiac trials included and 5 noninhalation and 5 inhalation agents as the comparator.
- A trend was noted when a subanalysis was performed with propofol as a comparator (1/544 [0.2%] v 6/546 [1.1%], p=0.05, with 16 studies included).