Division of Vascular and Endovascular Surgery, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Mass; Department of Vascular Surgery, University Medical Center, Utrecht, The Netherlands.
Division of Vascular and Endovascular Surgery, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Mass; Department of Surgery, Massachusetts General Hospital, Boston, Mass.
J Vasc Surg. 2018 Jan;67(1):183-190.e1. doi: 10.1016/j.jvs.2017.05.114. Epub 2017 Aug 16.
Preoperative anemia and blood transfusions are associated with worse outcomes after surgery. However, the impact of preoperative anemia and transfusions on outcomes after carotid endarterectomy (CEA) is unknown.
CEA patients from 2011 to 2015 in the American College of Surgeons National Surgical Quality Improvement Program Targeted Vascular module were compared by the presence of preoperative anemia (hematocrit <36%) after stratification by symptom status. Multivariable analysis accounted for differences in baseline characteristics. We included an interaction term in our multivariable model to assess whether the effect of anemia differed significantly between patients who received a perioperative transfusion and those who did not, with 30-day mortality as our primary outcome.
Of 16,068 patients, 6734 (42%) were symptomatic, of whom 1500 (22%) had anemia. Of the 9334 asymptomatic patients, 1935 (21%) had anemia. Both symptomatic and asymptomatic anemic patients were more likely to be transfused perioperatively compared with nonanemic patients, with 7.0% vs 0.4%, and 5.8% vs 0.7% (both P < .001). Among symptomatic patients, those with anemia compared with those without had a higher rate of 30-day mortality (2.5% vs 0.7%; P < .001). After adjustment, anemic symptomatic patients had a higher 30-day mortality risk (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.9-5.0; P < .001) compared with nonanemic symptomatic patients. In addition, in symptomatic patients, we found a significant interaction between anemia and perioperative transfusion on the outcome of 30-day mortality (P = .004), with a higher risk in perioperatively transfused symptomatic patients with anemia (OR, 7.8; 95% CI, 3.4-18.0; P < .001) than in symptomatic patients with anemia who did not receive a perioperative transfusion (OR, 2.3; 95% CI, 1.4-3.9; P = .002). In asymptomatic patients, anemic and nonanemic patients had comparable 30-day mortality rates (0.9% vs 0.6%; P = .2). After adjustment, anemia was not associated with 30-day mortality in asymptomatic patients (OR, 1.0; 95% CI, 0.5-2.0; P = .9), nor did we identify an interaction between anemia and perioperative transfusion in asymptomatic patients (P = .1). Patients who received a preoperative transfusion had a higher 30-day mortality rate than anemic patients not receiving preoperative transfusion in both symptomatic (n = 31, 9.7% vs 2.5%; P = .04) and asymptomatic patients (n = 21, 9.5% vs 0.9%; P = .02).
Preoperative anemia is a risk factor for 30-day mortality after CEA in symptomatic patients but not in asymptomatic patients. These results should be factored into the selection of symptomatic patients for CEA and dissuade treatment of asymptomatic patients scheduled for CEA who need a preoperative transfusion.
术前贫血和输血与手术后的不良结果相关。然而，术前贫血和输血对颈动脉内膜切除术（CEA）结果的影响尚不清楚。
比较 2011 年至 2015 年美国外科医师学会国家手术质量改进计划靶向血管模块中术前贫血（红细胞压积＜36%）患者的症状状态分层。多变量分析考虑了基线特征的差异。我们在多变量模型中加入了一个交互项，以评估在接受围手术期输血和未接受输血的患者中，贫血的影响是否有显著差异，以 30 天死亡率为主要结局。
在 16068 例患者中，6734 例（42%）为症状性，其中 1500 例（22%）有贫血。9334 例无症状患者中，1935 例（21%）有贫血。与非贫血患者相比，无论是症状性还是无症状性贫血患者，围手术期输血的可能性更大，分别为 7.0%与 0.4%，5.8%与 0.7%（均 P＜0.001）。在症状性患者中，贫血患者 30 天死亡率高于非贫血患者（2.5%与 0.7%；P＜0.001）。调整后，贫血症状性患者 30 天死亡率风险较高（比值比[OR]，3.1；95%置信区间[CI]，1.9-5.0；P＜0.001）。此外，在症状性患者中，我们发现贫血和围手术期输血对 30 天死亡率的结果存在显著的交互作用（P=0.004），与未接受围手术期输血的贫血症状性患者相比，接受围手术期输血的贫血症状性患者的风险更高（OR，7.8；95%CI，3.4-18.0；P＜0.001）。在无症状患者中，贫血和非贫血患者的 30 天死亡率相当（0.9%与 0.6%；P=0.2）。调整后，贫血与无症状患者的 30 天死亡率无关（OR，1.0；95%CI，0.5-2.0；P=0.9），我们也没有发现无症状患者中贫血和围手术期输血之间存在交互作用（P=0.1）。接受术前输血的患者与未接受术前输血的贫血患者相比，30 天死亡率更高，在症状性患者（n=31，9.7%与 2.5%；P=0.04）和无症状患者（n=21，9.5%与 0.9%；P=0.02）中均如此。
术前贫血是症状性患者 CEA 后 30 天死亡率的危险因素，但不是无症状患者的危险因素。这些结果应纳入症状性患者 CEA 的选择，并劝阻计划接受 CEA 且需要术前输血的无症状患者接受治疗。
