Cho Sung-Ae, Chang Minhye, Lee Seok-Jin, Sung Tae-Yun, Cho Choon-Kyu
Department of Anaesthesiology and Pain Medicine, Konyang University Hospital, Konyang University College of Medicine, Daejeon, Korea.
Ann Geriatr Med Res. 2022 Jun;26(2):175-182. doi: 10.4235/agmr.22.0053. Epub 2022 Jun 20.
Older patients are more vulnerable to inadvertent perioperative hypothermia. Prewarming contributes to the prevention of inadvertent perioperative hypothermia in patients under general or neuraxial anesthesia. However, the effects of brachial plexus block (BPB) on thermoregulation and the efficacy of prewarming in the prevention of hypothermia in older patients undergoing surgery with BPB remain unclear. This study evaluated the effects of BPB on thermoregulation and the efficacy of prewarming during BPB in older patients.
Patients aged ≥65 years were randomly allocated to receive either standard preoperative insulation (control group, n=20) or preanesthetic forced-air warming for 20 minutes before BPB (prewarming group, n=20). During the perioperative period, tympanic temperatures were measured. Thermal comfort scores and shivering grades were also obtained.
The tympanic temperatures at the end of surgery did not differ between the groups (36.9°C±0.5°C and 37.0°C±0.4°C in the control and prewarming groups, respectively; p=0.252). The maximum temperature change was significantly lower in the prewarming group compared to the control group (0.36°C±0.4°C and 0.65°C±0.3°C, respectively; p=0.013). The hypothermia incidence and severity, thermal comfort scores, and shivering grades did not differ between the groups.
Regardless of the application of prewarming, BPB did not cause a clinically significant impairment of thermoregulation. Moreover, the efficacy of prewarming appeared to be low; thus, it may not be routinely required in patients undergoing orthopedic hand surgery under BPB.
老年患者更容易在围手术期发生意外体温过低。术前预热有助于预防全身麻醉或神经轴索麻醉患者的围手术期意外体温过低。然而，臂丛神经阻滞（BPB）对体温调节的影响以及术前预热在预防接受BPB手术的老年患者体温过低方面的效果仍不明确。本研究评估了BPB对体温调节的影响以及老年患者在BPB期间进行术前预热的效果。
年龄≥65岁的患者被随机分配接受标准术前保温（对照组，n = 20）或在BPB前进行20分钟的麻醉前强制空气加温（预热组，n = 20）。在围手术期，测量鼓膜温度。还获得了热舒适度评分和寒战分级。
两组患者手术结束时的鼓膜温度无差异（对照组和预热组分别为36.9°C±0.5°C和37.0°C±0.4°C；p = 0.252）。预热组的最大温度变化明显低于对照组（分别为0.36°C±0.4°C和0.65°C±0.3°C；p = 0.013）。两组之间的体温过低发生率和严重程度、热舒适度评分以及寒战分级无差异。
无论是否进行预热，BPB均未导致临床上显著的体温调节受损。此外，预热的效果似乎较低；因此，在接受BPB的骨科手部手术患者中可能无需常规进行预热。
