Grant F C, Laupacis A, O'Connor A M, Rubens F, Robblee J
Department of Epidemiology and Community Medicine, University of Ottawa, Ont.
CMAJ. 2001 Apr 17;164(8):1139-44.
Patients undergoing open-heart surgery frequently require one or more blood transfusions. Because of the risks of receiving blood from volunteer donors, some patients choose to donate their own blood before surgery. This reduces their risk of exposure to volunteer-donated blood, but it increases their chance of receiving any transfusion, either of self-donated or volunteer-donated blood. Also, preoperative hemoglobin levels tend to be lower in patients who donate their own blood, and surgeons may be more likely to give transfusions to patients with self-donated blood. To help patients decide whether to donate their blood before surgery, we designed a decision aid comprising a booklet and audiotape and assessed its effectiveness.
The 59 study subjects were a sample of consecutive patients referred to the Ottawa Heart Institute between Oct. 1, 1998, and Jan. 5, 1999, for future coronary artery bypass grafting, valve surgery or combined surgery. All were eligible to donate blood. Initial questionnaires were administered in the clinic by a physician or study nurse, and follow-up questionnaires were completed at home and mailed in after use of the decision aid. Outcome measures included patients' knowledge, values (importance ratings), preferences for transfusion methods, decisional conflict (the amount of uncertainty about the course of action to take), risk perception and acceptability of the decision aid.
Mean knowledge scores on a 15-item test increased from 67% correct responses before the decision aid to 85% correct responses after use of the aid (p < 0.001); the effect was similar when the patients were divided into subgroups according to education level. The number of patients favouring donating their own blood increased from 41 (69%) before to 45 (76%) after use of the aid. Nine (64%) of 14 initially uncertain patients preferred autologous donation after use of the aid. The overall mean score for decisional conflict was unchanged, at 1.7, which indicated a low level of uncertainty. Risk perception improved, from 0%-14% correct responses on an 8-item test before the aid to 18%-60% correct responses after use of the aid. The decision aid was acceptable to the majority of patients, and 95% indicated that they would recommend it to others.
The decision aid improved knowledge and risk perceptions of blood donation and transfusion, and it helped uncertain patients to make choices.
接受心脏直视手术的患者常常需要接受一次或多次输血。由于接受志愿供血者血液存在风险，一些患者选择在手术前自体献血。这降低了他们接触志愿供血者血液的风险，但增加了他们接受任何输血的几率，无论是自体献血还是志愿供血者的血液。此外，自体献血的患者术前血红蛋白水平往往较低，外科医生可能更倾向于给自体献血的患者输血。为了帮助患者决定是否在手术前自体献血，我们设计了一种决策辅助工具，包括一本小册子和一盘录音带，并评估了其效果。
59名研究对象是1998年10月1日至1999年1月5日期间连续被转诊至渥太华心脏研究所、计划未来进行冠状动脉搭桥术、瓣膜手术或联合手术的患者样本。所有患者均有资格献血。初始问卷由医生或研究护士在诊所发放，后续问卷在患者在家使用决策辅助工具后完成并邮寄回来。结果指标包括患者的知识、价值观（重要性评分）、对输血方式的偏好、决策冲突（对采取何种行动方案的不确定程度）、风险认知以及对决策辅助工具的接受度。
在一项包含15个项目的测试中，平均知识得分从使用决策辅助工具前的67%正确回答提高到使用后的85%正确回答（p < 0.001）；根据教育水平将患者分为亚组时，效果相似。倾向于自体献血的患者数量从使用前的41名（69%）增加到使用后的45名（76%）。14名最初不确定的患者中有9名（64%）在使用决策辅助工具后选择了自体献血。决策冲突的总体平均得分保持不变，为1.7，表明不确定程度较低。风险认知有所改善，在一项包含8个项目的测试中，使用决策辅助工具前正确回答率为0% - 14%，使用后为18% - 60%。大多数患者接受该决策辅助工具，95%的患者表示会向他人推荐。
该决策辅助工具提高了患者对献血和输血的知识及风险认知，并帮助不确定的患者做出选择。
