Bräuer Anselm, Bovenschulte Henning, Perl Thorsten, Zink Wolfgang, English Michael John Murray, Quintel Michael
Department of Anesthesiology, University of Göttingen, Göttingen, Germany.
Anesth Analg. 2009 Jan;108(1):192-8. doi: 10.1213/ane.0b013e31818e0cee.
Forced-air warming has gained acceptance as an effective means to prevent perioperative hypothermia. However, little is known about the influence of air flow and air temperature at the nozzle and the influence of heat distribution in the blankets on the efficacy of these systems.
We conducted a manikin study with heat flux transducers using five forced-air warming systems to determine the factors that are responsible for heat transfer from the blanket to the manikin.
There was no relation between air temperature at the nozzle of the power unit and the resulting heat transfer. There was also no relation between the air flow at the nozzle of the power unit and the resulting heat transfer. However, all blankets performed best at high air flows above 19 L/s. The heat exchange coefficient, the mean temperature gradient between the blanket and the manikin correlated positively with the resulting heat transfer and the difference between the minimal and maximal blanket temperature correlated negatively with the resulting heat transfer.
The efficacy of forced-air warming systems is primarily determined by the blanket. Modern power units provide sufficient heat energy to maximize the ability of the blanket to warm the patient. Optimizing blanket design by optimizing the mean temperature gradient between the blanket and the manikin (or any other surface) with a very homogeneous temperature distribution in the blanket will enable the manufacturers to develop better forced-air warming systems.
强制空气加温已被公认为预防围手术期体温过低的有效方法。然而，对于喷嘴处的气流和空气温度以及毯子中的热分布对这些系统功效的影响，人们了解甚少。
我们使用五个强制空气加温系统，通过热通量传感器对人体模型进行了研究，以确定导致热量从毯子传递到人体模型的因素。
动力装置喷嘴处的空气温度与产生的热传递之间没有关联。动力装置喷嘴处的气流与产生的热传递之间也没有关联。然而，所有毯子在高于19升/秒的高气流下表现最佳。热交换系数，即毯子与人体模型之间的平均温度梯度与产生的热传递呈正相关，毯子最低温度与最高温度之间的差值与产生的热传递呈负相关。
强制空气加温系统的功效主要由毯子决定。现代动力装置提供了足够的热能，以使毯子温暖患者的能力最大化。通过优化毯子与人体模型（或任何其他表面）之间的平均温度梯度以及毯子内非常均匀的温度分布来优化毯子设计，将使制造商能够开发出更好的强制空气加温系统。
