Preoperative beta-blocker usage: is it really worthy of being a quality indicator?

BACKGROUND: Since 2007, the use of preoperative β-blockers has been used as a quality standard for patients undergoing coronary artery bypass graft surgery. Recent studies have called into question of the benefit of empiric preoperative β-blocker use.

METHODS: Data were extracted from our Society of Thoracic Surgeons certified database for patients undergoing isolated coronary artery bypass graft surgery from 2000 to 2008. We compared the outcomes for patients who received preoperative β-blockers with those of patients who did not.

RESULTS: The study group had 12,855 patients, of whom 7,967 (62.0%) were treated preoperatively with β-blockers. Using propensity matching, we selected two matched groups of 4,474 patients with preoperative β-blocker use and 4,474 not using preoperative β-blockers. In the unmatched cohort, only deep sternal infection (0.3% versus 0.5% without β-blockers; p=0.032), pneumonia (1.9% versus 2.4% without β-blockers; p=0.039), and intraoperative blood usage (37.2% versus 34.1% without β-blockers; p<0.001) reached statistically significant difference. In the matched groups, there was no difference between adverse event rates in patients treated with β-blockers and those who were not. The number of patients requiring intraoperative blood product use was significantly higher among β-blocker-treated patients (p=0.004). Calculating the adjusted odds ratios showed that in the matched groups, the preoperative use of β-blockers was not an independent predictor of mortality.

CONCLUSIONS: A rational for preoperative β-blockade exists. However, as with any medical intervention, its application should be tailored to specific clinical scenarios. With no differences in mortality or morbidity, our findings do not support preoperative β-blockade as a useful quality indicator for coronary artery bypass graft surgery.