Taylor Rebecca C, Pagliarello Giuseppe
General Surgery, University of Ottawa, Ottawa, Ont.
Can J Surg. 2003 Jun;46(3):216-22.
The benefit of administering beta-adrenergic blocking agents perioperatively to surgical patients at high risk for myocardial ischemia has been demonstrated in several well-designed randomized controlled trials. These benefits have included a reduction in the incidence of myocardial complications and an improvement in overall survival for patients with evidence of or at risk for coronary artery disease (CAD). We designed a retrospective study at the Ottawa Civic Hospital to investigate the use of beta-blockers in the perioperative period for high-risk general surgery patients who underwent laparotomy and to explore the reasons for failure to prescribe or administer beta-blockers when indicated.
All 236 general surgery patients over the age of 50 years who underwent laparotomy for major gastrointestinal surgery between Jan. 1, 2001, and Dec. 31, 2001, were assigned a cardiac risk classification using the risk stratification described by Mangano and colleagues. The perioperative prescription and administration of beta-blockers were noted as were the patient's heart rate and blood pressure parameters for the first postoperative week, in-hospital adverse cardiac events and death.
Of the 143 patients classified as being at risk for CAD or having definite evidence of CAD, 87 (60.8%) did not receive beta-blockers perioperatively. Of those who did, 43 were previously on beta-blockers and 13 had them ordered preoperatively. Patients with definite CAD were significantly more likely than others to receive beta-blockers perioperatively (p < 0.001), as were patients seen by an anesthesiologist or an internist preoperatively (p < 0.001). Twenty (33%) of the 61 patients who were already taking beta-blockers preoperatively had them inappropriately discontinued postoperatively. Once prescribed by the physician, beta-blockers were administered by the nurses irrespective of nil par os status. The mean heart rate and blood pressure parameters for patients receiving beta-blockers postoperatively was 82 beats/min and 110 mm Hg, respectively, and these values were not significantly different from the mean heart rate of patients not receiving beta-blockers. The number of postoperative cardiac events was significantly higher in patients with definite evidence of CAD, and among this group, the use of beta-blockers was associated with a significant reduction in postoperative cardiac events. This was not true for patients at risk for CAD or patients with no risk of CAD.
A significant proportion (> 60%) of general surgery patients who were identified as having definite evidence of, or being at risk for, CAD were not prescribed beta-blockers preoperatively. More than 30% of patients who were on beta-blockers preoperatively did not have them reordered postoperatively. These results may reflect controversy surrounding the recommendations, miscommunication between surgeons and anesthesiologists and errors in postoperative ordering.
在几项精心设计的随机对照试验中，已证明围手术期对有心肌缺血高风险的外科手术患者使用β-肾上腺素能阻滞剂有益。这些益处包括心肌并发症发生率降低，以及对有冠状动脉疾病（CAD）证据或有CAD风险的患者总体生存率的改善。我们在渥太华市民医院开展了一项回顾性研究，以调查β受体阻滞剂在接受剖腹手术的高风险普通外科手术患者围手术期的使用情况，并探讨在有指征时未开具或未使用β受体阻滞剂的原因。
对2001年1月1日至2001年12月31日期间因重大胃肠手术接受剖腹手术的所有236名年龄超过50岁的普通外科手术患者，使用Mangano及其同事描述的风险分层方法进行心脏风险分类。记录围手术期β受体阻滞剂的处方和使用情况，以及患者术后第一周的心率和血压参数、院内不良心脏事件和死亡情况。
在143名被分类为有CAD风险或有明确CAD证据的患者中，87名（60.8%）在围手术期未接受β受体阻滞剂治疗。在接受治疗的患者中，43名之前一直在服用β受体阻滞剂，13名术前被医嘱使用。有明确CAD的患者比其他患者在围手术期接受β受体阻滞剂治疗的可能性显著更高（p<0.001），术前看过麻醉医生或内科医生的患者也是如此（p<0.001）。61名术前已在服用β受体阻滞剂的患者中有20名（33%）术后被不恰当地停用。一旦医生开具医嘱，护士会使用β受体阻滞剂，而不考虑患者禁食状态。术后接受β受体阻滞剂治疗的患者的平均心率和血压参数分别为82次/分钟和110毫米汞柱，这些值与未接受β受体阻滞剂治疗的患者的平均心率无显著差异。有明确CAD证据的患者术后心脏事件数量显著更高，在这组患者中，使用β受体阻滞剂与术后心脏事件显著减少相关。对于有CAD风险的患者或无CAD风险的患者，情况并非如此。
很大一部分（>60%）被确定有明确CAD证据或有CAD风险的普通外科手术患者术前未开具β受体阻滞剂。超过30%术前服用β受体阻滞剂的患者术后未重新开具医嘱。这些结果可能反映了围绕这些建议的争议、外科医生和麻醉医生之间的沟通不畅以及术后医嘱错误。
