Chinnadurai Sathya K, Johnson James G, Langan Jennifer N
Chicago Zoological Society, Brookfield Zoo, Brookfield, Illinois;, Email:
Chicago Zoological Society, Brookfield Zoo, Brookfield, Illinois Zoological and Aquatic Animal Residency Program, Urbana, Illinois, Columbus Zoo and Aquarium, Powell, Ohio.
J Am Assoc Lab Anim Sci. 2017 May 1;56(3):318-321.
Perianesthetic hypothermia is one of the most common complications in veterinary anesthesia, especially in small patients with a large body surface area to mass ratio. During anesthesia, body heat can be lost through 4 mechanisms-radiation, convection, conduction, and evaporation-but anesthetists frequently address only one mechanism at a time. Here we sought to evaluate 3 methods of preventing perianesthetic hypothermia in callimicos (Callimico goeldii). In our experience, these small NHP routinely become hypothermic under even brief inhalant anesthesia. To address multiple routes of heat loss, animals received 1 of 3 treatments: 1) placement of a reflective blanket over the patient to limit radiative heat loss to the surrounding environment; 2) placement of a reflective blanket and use of a heated anesthetic circuit, which warmed the inspired air to 104 °F (40 °C), and 3) placement under the patient of a forced-air warming blanket set at 109.4 °F (43 °C). Sources of radiative heat loss were assessed by using infrared thermography. Each animal was anesthetized with isoflurane and maintained in sternal recumbency in a temperature-controlled room (65 °F; 18.3 °C); esophageal core body temperature was monitored every 5 min for a total of 30 min. The rate of heat loss did not differ between the use of a reflective blanket with or without a heated anesthetic circuit. Animals provided the forced-air warming blanket experienced a slight increase in average body temperature. According to these findings, an underbody warm-air blanket provided the best protection against hypothermia for callimicos in sternal recumbency.
麻醉期间体温过低是兽医麻醉中最常见的并发症之一,尤其是在体表面积与体重之比大的小型动物患者中。在麻醉期间,身体热量可通过四种机制散失——辐射、对流、传导和蒸发——但麻醉师通常一次只处理一种机制。在此,我们试图评估三种预防夜猴(Callimico goeldii)麻醉期间体温过低的方法。根据我们的经验,这些小型非人灵长类动物即使在短暂的吸入麻醉下也经常会体温过低。为了解决多种散热途径,动物接受了以下三种治疗方法之一:1)在患者身上放置反光毯,以限制向周围环境的辐射热损失;2)放置反光毯并使用加热麻醉回路,将吸入的空气加热到104°F(40°C),以及3)在患者下方放置温度设置为109.4°F(43°C)的强制空气加热毯。通过红外热成像评估辐射热损失的来源。每只动物用异氟烷麻醉,并在温度控制的房间(65°F;18.3°C)中保持胸骨卧位;每隔5分钟监测一次食管核心体温,共监测30分钟。使用或不使用加热麻醉回路的反光毯之间的热损失率没有差异。使用强制空气加热毯的动物平均体温略有升高。根据这些发现,对于处于胸骨卧位的夜猴,底部暖空气毯对体温过低提供了最佳保护。