Elmore J R, Franklin D P, Youkey J R, Oren J W, Frey C M
Section of Vascular Surgery, Geisinger Medical Center, Penn State Geisinger Health System, Danville, PA 17822-2150, USA.
J Vasc Surg. 1998 Dec;28(6):984-92; discussion 992-4. doi: 10.1016/s0741-5214(98)70024-2.
Mild hypothermia has been suggested to be protective against tissue ischemia during aortic operations. However, recent studies have documented detrimental cardiac effects of hypothermia during a variety of operative procedures. The influence of different warming methods and the impact of hypothermia during standard aortic procedures was assessed.
One hundred patients who underwent repair of infrarenal aortic aneurysms or aortoiliac occlusive disease were prospectively randomized into 2 groups, receiving either a circulating water mattress or a forced air warming blanket. Adjuvant warming methods were standardized. The day before surgery, 48-hour Holter monitors were applied and interpreted by a cardiologist blinded to the treatment. Randomization resulted in equivalent groups with regard to patient history, indications for surgery, body mass index, length of surgery, and fluid requirements.
Core temperatures were significantly warmer during surgery (36.3 degrees C +/- 0.7 degrees C vs 35.4 +/- 0.8 degrees C) and after surgery (36.4 degrees C +/- 0.7 degrees C vs 35.6 degrees C +/- 0.9 degrees C) in patients with forced air warming (P <.001). The circulating water mattress group had significantly more metabolic acidosis perioperatively (P =.03). Postoperative length of stay, cardiac complications, and death rates were not significantly different. Subgroup analysis of 83 aneurysm patients comparing normothermia with hypothermia (temperature less than 36 degrees C) on arrival to the recovery room identified decreased cardiac output (P =.02), thrombocytopenia (P =.02), elevated prothrombin time (P =.04), and inferior Acute Physiology and Chronic Health Evaluation (APACHE) II scores (P <.001) in the hypothermic group. Holter analysis revealed more sinus tachycardia (ST) segment changes and ventricular tachycardia in hypothermic aneurysm patients (P =.05).
Patients treated with forced air blankets had significantly less metabolic acidosis and were kept significantly warmer than those treated with circulating water mattresses. Patients with aneurysms that were kept normothermic had a significantly improved clinical profile, with fewer cardiac events on the Holter recordings. We therefore conclude that (1) normothermia is protective for infrarenal aortic surgical patients; and (2) forced air warming blankets provide improved temperature maintenance compared with circulating water mattresses.
有人提出轻度低温对主动脉手术期间的组织缺血具有保护作用。然而，最近的研究记录了低温在各种手术过程中对心脏的有害影响。评估了不同升温方法的影响以及标准主动脉手术期间低温的影响。
100例行肾下腹主动脉瘤修复术或主-髂动脉闭塞性疾病手术的患者被前瞻性随机分为两组，分别接受循环水床垫或强制空气加温毯。辅助升温方法标准化。手术前一天，应用48小时动态心电图监测仪，并由对治疗不知情的心脏病专家进行解读。随机分组后，两组在患者病史、手术指征、体重指数、手术时长和液体需求量方面相当。
使用强制空气加温的患者在手术期间（36.3℃±0.7℃对35.4±0.8℃）和手术后（36.4℃±0.7℃对35.6℃±0.9℃）核心体温明显更高（P<.001）。循环水床垫组围手术期代谢性酸中毒明显更多（P=.03）。术后住院时间、心脏并发症和死亡率无显著差异。对83例动脉瘤患者进行亚组分析，比较到达恢复室时体温正常与体温过低（体温低于36℃）的情况，发现低温组心输出量降低（P=.02）、血小板减少（P=.02）、凝血酶原时间延长（P=.04）以及急性生理与慢性健康状况评分（APACHE）II评分较低（P<.001）。动态心电图分析显示，低温动脉瘤患者窦性心动过速（ST）段改变和室性心动过速更多（P=.05）。
使用强制空气加温毯治疗的患者代谢性酸中毒明显更少，体温明显高于使用循环水床垫治疗的患者。体温正常的动脉瘤患者临床情况明显改善，动态心电图记录的心脏事件更少。因此，我们得出结论：（1）体温正常对肾下腹主动脉手术患者具有保护作用；（2）与循环水床垫相比，强制空气加温毯能更好地维持体温。
