Protocol implementation in anesthesia: beta-blockade in non-cardiac surgery patients

An audit of intensive care unit (ICU) patients with perioperative myocardial ischemia and/or infarction (PMI/I) suggested under-use of prophylactic beta-adrenergic blocking drugs (ABDs). A multidisciplinary team developed an institutional protocol to identify at-risk patients, to standardize and facilitate prophylactic beta-adrenergic blockade, and to improve management of such patients. We report a retrospective assessment of the efficiency of program implementation.

Eligible preanesthesia assessment unit patients received metoprolol for one to four weeks prior to surgery, intraoperatively, and postoperatively. Patients with PMI/I requiring ICU admission were tracked from January 2002 to December 2004. The protocol was implemented in May 2003. The efficiency of program implementation was evaluated during two months of normal operating room activity (September 2003 and February 2004).

The use of ABDs increased during the audit. Preoperative use increased from 31% in September 2003 to 39% of eligible patients in February 2004, with a stable surgical population. The incidence of patients with PMI/I admitted to ICU decreased from 2.6/1,000 surgical cases pre-implementation to 1.6/1,000 surgical cases post-implementation (P=0.025). For the whole hospital, implementation was associated with a decrease in PMI/I incidence from 5.9 to 2.0/1,000 surgical cases (P<0.001).

Heightened awareness and standardization of perioperative beta-blockade coincided with an increase in metoprolol use in at-risk patients and reduction in PMI/I. There was an increase in at-risk patients receiving prophylactic ABDs, a reduction in PMI/I diagnoses throughout the hospital, and reduced ICU patient admissions with PMI/I.