Perioperative beta-blockade: guidelines and practice in New Zealand

The aim of our study was to describe the knowledge and practice of New Zealand anaesthetists in relation to perioperative beta-adrenergic blockade, and to define barriers to implementation of perioperative beta-blockade in surgical patients at risk of myocardial ischaemia. A survey was sent to 400 New Zealand specialist anaesthetists. Information was sought on their knowledge and current practice relating to perioperative beta-blockade, and the barriers encountered to implementing therapy. The response rate was 59%. Perioperative beta-blockade was seen as beneficial in at risk patients by 95% of responding anaesthetists, but practice varied widely. Only 45% of anaesthetists always or usually commenced a beta blocker perioperatively, a department protocol was available to only 20%, and understanding of indications and contraindications to beta-blockade varied. There were logistical difficulties when initiating and monitoring perioperative beta-blocker regimens, and where treatment required multidisciplinary commitment. The lack of clarity of the guidelines was also a barrier to more widespread use. Difficulties were encountered relating general guidelines to individual patients, when co-morbidities, concurrent treatment and the influence of regional or general anaesthesia may influence the risk/benefit ratio. This study has identified variations in practice and reasons why New Zealand anaesthetists use of perioperative beta-blockers is at odds with published guidelines. Deficiencies in the guidelines are part of the problem. However, even with consensus on guidelines, effective multidisciplinary strategies will be required to optimize treatment of patients at risk of perioperative cardiac events.