Mariak Z, Lebkowski W, Lysoń T, Lewko J, Piekarski P
Kliniki Neurochirurgii, Akademii Medycznej w Białymstoku.
Neurol Neurochir Pol. 1999 Nov-Dec;33(6):1325-37.
Mild hypothermia may occur spontaneously or, because of its putative neuroprotective effect, may be induced purposefully during neurosurgical procedures. Though the brain is the organ targeted for the purpose of neuroprotection, little is known about its temperature during general anaesthesia and craniotomy. The purpose of this study was to define the relations between core, skin and brain temperature during craniotomy and to compare two modes of inducing thermal insulation in patients during operative procedures. To achieve this we recorded core: rectal (Tre), oesophageal (Tes) and tympanic (Try) temperature, brain temperature in the subdural space (Tsd), and skin temperature on the thigh (Tfe), forehead (Tfr) and sternum (Tst) in 15 patients undergoing standard procedure for aneurysm clipping. In 13 patients the core temperature decreased, whereas skin temperature increased, after induction of general anaesthesia with isofluran. Nevertheless the mean body temperature remained unchanged, thus supporting the view that the cause of the resultant core hypothermia was heat redistribution between the thermal core and the periphery. Special thermofoil proved to be only as effective as a plain cotton blanket in preventing further heat loss during the later phases of the operation. Brain temperature was found to be the lowest core temperature throughout the procedure. It differed by as much as 0.1-1.2 degrees C from rectal temperature (mean 0.75 +/- 0.41 degree C) and reached the level of mild hypothermia (below 35 degrees C) even in those patients in whom rectal temperature indicated the state of normothermia. Furthermore tympanic and oesophageal temperature was on average 0.5 degree C higher than brain temperature. In conclusion, temperature measurements obtained in standard sites do not reflect brain temperature reliably during craniotomy and general anaesthesia. This indicates that the direct measurement of intracranial temperature is necessary for correct estimation of brain hypothermia.
轻度低温可能自发出现，或者由于其假定的神经保护作用，在神经外科手术过程中可能被有意诱发。尽管大脑是神经保护的目标器官，但对于全身麻醉和开颅手术期间大脑的温度却知之甚少。本研究的目的是确定开颅手术期间核心温度、皮肤温度和大脑温度之间的关系，并比较手术过程中两种诱导患者保温的方式。为实现这一目的，我们记录了15例接受标准动脉瘤夹闭手术患者的核心温度：直肠温度（Tre）、食管温度（Tes）和鼓膜温度（Try），硬脑膜下间隙的大脑温度（Tsd），以及大腿、前额和胸骨的皮肤温度（Tfe、Tfr、Tst）。13例患者在异氟烷全身麻醉诱导后，核心温度下降，而皮肤温度升高。然而，平均体温保持不变，因此支持了这样的观点，即由此产生的核心低温的原因是热核心与外周之间的热量重新分布。在手术后期，特制的隔热锡纸在防止进一步热量散失方面仅与普通棉毯一样有效。发现在整个手术过程中大脑温度是最低核心温度。它与直肠温度相差高达0.1 - 1.2摄氏度（平均0.75 ± 0.41摄氏度），即使在直肠温度显示为正常体温的患者中，大脑温度也达到了轻度低温水平（低于35摄氏度）。此外，鼓膜温度和食管温度平均比大脑温度高0.5摄氏度。总之，在标准部位获得的温度测量值在开颅手术和全身麻醉期间不能可靠地反映大脑温度。这表明直接测量颅内温度对于正确估计脑低温是必要的。
