Preoperative β-blocker use: impact of national guidelines on clinical practice

Study ObjectiveTo determine if recommendations regarding perioperative β-blocker therapy were followed by an increase in the number of eligible presurgical patients receiving β-blockers and the number achieving the recommended heart rate (HR <60 beats per minute [bpm]).DesignRetrospective, observational study.SettingTertiary-care teaching hospital.MeasurementsThe records of all 718 patients who underwent elective vascular surgery or coronary artery bypass grafting between January 2001 and March 2002 (pre-guideline) and those who did so between April 2002 and September 2003 (post-guideline) were reviewed. Percentage of eligible patients who received β-blockers preoperatively and the target HR achieved in pre-guideline versus post-guideline patients were recorded. Differences were assessed using the unpaired t test and χ2 analysis. A P value of less than 0.05 is reported.Main ResultsFifty percent of the post-guideline patients in the vascular surgery group were receiving β-blockers at the time of preanesthetic evaluation versus 48% of pre-guideline patients (P = nonsignificant [NS]). Mean HR in the vascular surgery post-guideline β-blocker group (70 ± 14 bpm) was higher than in the pre-guideline β-blocker group (65 ± 11 bpm) (P < 0.01). Only 22% of those vascular surgery patients in the post-guideline group who were taking β-blockers achieved the target HR of less than 60 bpm versus 29% of the vascular surgery patients taking β-blockers in the pre-guideline group (P = NS). In the coronary artery bypass grafting group, 80% of post-guideline patients received β-blocker before anesthesia assessment versus 75% of pre-guideline patients (P = NS). Mean HR in the post-guideline β-blocker group (67 ± 15 bpm) was similar to the pre-guideline β-blocker group (64 ± 13 bpm) (P = NS). Only 28% of the post-guideline patients who were receiving β-blockers achieved the target HR of less than 60 bpm, which was not significantly different from the 17% achieved in the pre-guideline group (P = NS).ConclusionAt our institution, preoperative β-blocker use was not significantly changed by publication of the recommendations.