Nesher Nahum, Insler Steven R, Sheinberg Nehama, Bolotin Gil, Kramer Amir, Sharony Ram, Paz Yosef, Pevni Dimitri, Loberman Dan, Uretzky Gideon
Department of Cardiothoracic Surgery, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, 6 Weizman Street, Tel-Aviv 64239, Israel.
Heart Surg Forum. 2002;5(4):373-80.
Most patients undergoing coronary artery bypass surgery demonstrate perioperative mild-to-moderate hypothermia (<36 degrees C). Patients undergoing off-pump coronary artery bypass (OPCAB) grafting may become even more severely hypothermic for want of cardiopulmonary bypass rewarming. One consequence is increased circulating catecholamine levels that induce an elevated systemic vascular resistance (SVR), which causes a subsequent deterioration in cardiac output.
We assessed the ability of the Allon thermoregulatory (AT) system to maintain normothermia and its impact on hemodynamics and myocardial function in patients undergoing OPCAB surgery. In this study, the first 60 of 120 suitable patients were assigned to AT (n = 40) or routine thermal care (RTC) (n = 20). Core body temperature, cardiac index (CI), SVR, and cardiac-specific troponin I (cTnI) were analyzed perioperatively for patients in both groups.
Core body temperature was significantly higher in the AT group (from 36.1 degrees C +/- 0.5 degrees C at induction of anesthesia to 37 degrees C +/- 0.5 degrees C during surgery) than in the RTC group (from 35.8 degrees C +/- 0.4 degrees C to 35.2 degrees C +/- 0.8 degrees C, respectively; P <.01). SVR was significantly lower, and CI was greater (at comparable time points), whereas cTnI levels in the AT group were lower than in the RTC group from the end of surgery until 24 hours postoperatively (7.4 +/- 17.7 g/L versus 31.9 +/- 47.4 g/L; P =.03). These findings indicate the possibility for less ischemic damage sustained intraoperatively in the AT group.
Maintenance of perioperative normothermia (36.5 degrees C-37.5 degrees C) during OPCAB procedures can be efficiently achieved with the Allon thermoregulation system. The system was found to be superior to other routinely used methods of temperature maintenance. Benefits may include lowering afterload (as expressed by reduced SVR), an improved CI, and attenuation of myocardial injury (as assessed by cTnI levels).
大多数接受冠状动脉搭桥手术的患者在围手术期会出现轻至中度体温过低（<36摄氏度）。由于缺乏体外循环复温，接受非体外循环冠状动脉搭桥（OPCAB）手术的患者体温过低可能会更加严重。一个后果是循环儿茶酚胺水平升高，导致全身血管阻力（SVR）升高，进而导致心输出量随后下降。
我们评估了Allon温度调节（AT）系统在接受OPCAB手术的患者中维持正常体温的能力及其对血流动力学和心肌功能的影响。在本研究中，120例合适患者中的前60例被分配至AT组（n = 40）或常规体温护理（RTC）组（n = 20）。对两组患者围手术期的核心体温、心脏指数（CI）、SVR和心肌特异性肌钙蛋白I（cTnI）进行分析。
AT组的核心体温显著高于RTC组（从麻醉诱导时的36.1摄氏度±0.5摄氏度升至手术期间的37摄氏度±0.5摄氏度），而RTC组分别从35.8摄氏度±0.4摄氏度降至35.2摄氏度±0.8摄氏度；P <.01）。在可比时间点，AT组的SVR显著更低，CI更高，而从手术结束至术后24小时，AT组的cTnI水平低于RTC组（7.4±17.7μg/L对31.9±47.4μg/L；P =.03）。这些发现表明AT组术中缺血损伤可能更小。
使用Allon温度调节系统可在OPCAB手术过程中有效维持围手术期正常体温（36.5摄氏度至37.5摄氏度）。该系统被发现优于其他常规使用的体温维持方法。益处可能包括降低后负荷（如通过降低SVR表示）、改善CI以及减轻心肌损伤（如通过cTnI水平评估）。
