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

STUDY OBJECTIVE: To determine if recommendations regarding perioperative beta-blocker therapy were followed by an increase in the number of eligible presurgical patients receiving beta-blockers and the number achieving the recommended heart rate (HR <60 beats per minute [bpm]). DESIGN: Retrospective, observational study. SETTING: Tertiary-care teaching hospital. MEASUREMENTS: The 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 beta-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 chi2 analysis. A P value of less than 0.05 is reported. MAIN RESULTS: Fifty percent of the post-guideline patients in the vascular surgery group were receiving beta-blockers at the time of preanesthetic evaluation versus 48% of pre-guideline patients (P = nonsignificant [NS]). Mean HR in the vascular surgery post-guideline beta-blocker group (70 +/- 14 bpm) was higher than in the pre-guideline beta-blocker group (65 +/- 11 bpm) (P < 0.01). Only 22% of those vascular surgery patients in the post-guideline group who were taking beta-blockers achieved the target HR of less than 60 bpm versus 29% of the vascular surgery patients taking beta-blockers in the pre-guideline group (P = NS). In the coronary artery bypass grafting group, 80% of post-guideline patients received beta-blocker before anesthesia assessment versus 75% of pre-guideline patients (P = NS). Mean HR in the post-guideline beta-blocker group (67 +/- 15 bpm) was similar to the pre-guideline beta-blocker group (64 +/- 13 bpm) (P = NS). Only 28% of the post-guideline patients who were receiving beta-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). CONCLUSION: At our institution, preoperative beta-blocker use was not significantly changed by publication of the recommendations.

Preoperative beta-blocker use: is titration to a heart rate of 60 beats per minute a consistently attainable goal?

STUDY OBJECTIVE: To quantify the prevalence of perioperative beta-blocker use and its impact on preoperative and preinduction heart rate (HR), in light of the recent publication of specific recommendations regarding perioperative beta-blocker use and desired HR. DESIGN: Retrospective observational study in patients who underwent elective and coronary artery bypass graft (CABG) surgery between January 2001 and March 2002. SETTING: Tertiary-care teaching hospital. MEASUREMENTS: Percentage of eligible patients who received beta-blockers preoperatively and the impact of non-protocol-based beta-blocker therapy on preadmission and preinduction HR were recorded. Differences were assessed with unpaired t test and chi(2) analysis; P < .05 was considered significant, with corrections for multiple comparisons. RESULTS: Of the patients who underwent vascular surgery, 9 had documented prior beta-blocker intolerance. Of the remaining 172 patients, 94.8% had indication for perioperative beta-blocker use. However, only 47.7% of the eligible patients received beta-blockers. Of the 155 CABG patients, 74.2% were taking beta-blockers preoperatively. Only 29% of vascular patients and 32% of CABG patients who were receiving beta-blockers had HR less than 60 beats per minute (bpm) at preadmission. The mean preadmission HR in vascular surgery patients was 65.2 +/- 11 and 73.2 +/- 13.8 bpm in beta-blocker and non-beta-blocker patients, respectively (P = .0001). In CABG surgery patients, preadmission HR values were 64.2 +/- 13 and 76.1 +/- 12 bpm in beta-blocker and non-beta-blocker patients, respectively (P = .001). The preinduction HR subsequently increased in the beta-blocker as well as in the non-beta-blocker groups. CONCLUSION: Only half of the patients who qualify to receive preoperative beta-blockers by current recommendations actually receive them before noncardiac surgery, and the majority of these patients have preadmission and preinduction HR less than 60 bpm. Targeting beta-blocker therapy treatment to an HR less than 60 bpm may not be readily achievable in many patients.