Blood pressure management during cardiac surgery: a survey of Canadian cardiac anesthesiologists, perfusionists, and cardiac surgeons.

PURPOSE

Clinicians presume a relationship between the management of blood pressure during cardiac surgery and postoperative morbidity and mortality. With limited evidence to inform practice, we surveyed Canadian cardiac anesthesiologists, perfusionists, and cardiac surgeons. We sought to solicit information to inform a trial evaluating the blood pressure management approach on outcomes after cardiac surgery.

METHODS

We iteratively developed a survey assessing the lowest and highest blood pressures respondents would target, the narrowest feasible blood pressure range to achieve, the range of blood pressure observed in clinical practice, and factors influencing targeted blood pressure before, during, and after cardiopulmonary bypass (CPB). We contacted leads from every Canadian hospital providing cardiac surgery to distribute the survey via a computerized link. We used a modified Dillman approach to optimize response rate. Responses were analyzed descriptively.

RESULTS

Of 819 clinicians surveyed, 532 (65%) responded. Respondents' lowest pooled mean arterial pressure (MAP) target, presented as mean (standard deviation [SD]), was 59 (6) mm Hg before CPB, 55 (7) mm Hg during CPB, and 60 (5) mm Hg after CPB. Respondents' highest pooled MAP target, presented as mean (SD), was 92 (10) mm Hg before CPB, 84 (7) mm Hg during CPB, and 75 (6) mm Hg after CPB. The narrowest feasible MAP range, presented as mean (SD), all respondents believed could be achieved was 19 (7) mm Hg before CPB, 16 (7) mm Hg during CPB, and 20 (7) mm Hg after CPB.

CONCLUSIONS

The responses to our survey support the clinical acceptability of a trial examining blood pressure target thresholds at the extreme ends of the range recommended by existing guidelines and the feasibility of maintaining blood pressure within a narrow target range.