Krieger D W, De Georgia M A, Abou-Chebl A, Andrefsky J C, Sila C A, Katzan I L, Mayberg M R, Furlan A J
Cerebrovascular Center, The Cleveland Clinic Foundation, Cleveland, Ohio, USA.
Stroke. 2001 Aug;32(8):1847-54. doi: 10.1161/01.str.32.8.1847.
Hypothermia is effective in improving outcome in experimental models of brain infarction. We studied the feasibility and safety of hypothermia in patients with acute ischemic stroke treated with thrombolysis.
An open study design was used. All patients presented with major ischemic stroke (National Institutes of Health Stroke Scale [NIHSS] score >15) within 6 hours of onset. After informed consent, patients with a persistent NIHSS score of >8 were treated with hypothermia to 32+/-1 degrees C for 12 to 72 hours depending on vessel patency. All patients were monitored in the neurocritical care unit for complications. A modified Rankin Scale was measured at 90 days and compared with concurrent controls.
Ten patients with a mean age of 71.1+/-14.3 years and an NIHSS score of 19.8+/-3.3 were treated with hypothermia. Nine patients served as concurrent controls. The mean time from symptom onset to thrombolysis was 3.1+/-1.4 hours and from symptom onset to initiation of hypothermia was 6.2+/-1.3 hours. The mean duration of hypothermia was 47.4+/-20.4 hours. Target temperature was achieved in 3.5+/-1.5 hours. Noncritical complications in hypothermia patients included bradycardia (n=5), ventricular ectopy (n=3), hypotension (n=3), melena (n=2), fever after rewarming (n=3), and infections (n=4). Four patients with chronic atrial fibrillation developed rapid ventricular rate, which was noncritical in 2 and critical in 2 patients. Three patients had myocardial infarctions without sequelae. There were 3 deaths in patients undergoing hypothermia. The mean modified Rankin Scale score at 3 months in hypothermia patients was 3.1+/-2.3.
Induced hypothermia appears feasible and safe in patients with acute ischemic stroke even after thrombolysis. Refinements of the cooling process, optimal target temperature, duration of therapy, and, most important, clinical efficacy, require further study.
低温对改善脑梗死实验模型的预后有效。我们研究了低温疗法应用于接受溶栓治疗的急性缺血性卒中患者的可行性与安全性。
采用开放研究设计。所有患者均在发病6小时内出现严重缺血性卒中（美国国立卫生研究院卒中量表[NIHSS]评分>15）。在获得知情同意后，NIHSS评分持续>8分的患者接受低温治疗，体温降至32±1摄氏度，持续12至72小时，具体时长取决于血管通畅情况。所有患者均在神经重症监护病房接受并发症监测。在90天时测量改良Rankin量表评分，并与同期对照进行比较。
10例平均年龄为71.1±14.3岁、NIHSS评分为19.8±3.3的患者接受了低温治疗。9例患者作为同期对照。从症状发作到溶栓的平均时间为3.1±1.4小时，从症状发作到开始低温治疗的平均时间为6.2±1.3小时。低温治疗的平均持续时间为47.4±20.4小时。在3.5±1.5小时内达到目标温度。低温治疗患者的非严重并发症包括心动过缓（n = 5）、室性早搏（n = 3）、低血压（n = 3）、黑便（n = 2）、复温后发热（n = 3）和感染（n = 4）。4例慢性心房颤动患者出现快速心室率，其中2例不严重，2例严重。3例患者发生心肌梗死，无后遗症。接受低温治疗的患者中有3例死亡。低温治疗患者在3个月时的平均改良Rankin量表评分为3.1±2.3。
即使在溶栓治疗后，诱导低温疗法应用于急性缺血性卒中患者似乎也是可行且安全的。冷却过程、最佳目标温度、治疗持续时间以及最重要的临床疗效等方面的改进需要进一步研究。
