Subayi L, Chergui K, Beydon L
Département d'anesthésie-réanimation, CHU d'Angers, France.
Ann Fr Anesth Reanim. 1998;17(7):699-708. doi: 10.1016/s0750-7658(98)80107-x.
Heat and moisture-exchanging filters (HMEFs) are increasingly used in clinical practice. At the same time, new scientific data are available which clarify the benefits of these devices.
We searched in the Medline database for all papers written in English or French, without limiting date of publication, using the following key-words separately or in combination: humidity, temperature, mechanical ventilation, equipment.
From the 200 articles provided by Medline, we selected those directly concerning HMEFs. Some older studies and those on HMEFs no longer available were excluded.
Principle data available from the literature were analysed.
Humidification and warming of the inspired gas mixture is mandatory during mechanical ventilation. There is a direct link between HMEF performance and the characteristics of tracheal secretions. This justified the recommendation for the use of HMEFs with a humidity output above 30 mg of water per litre of gas mixture. In this case, HMEFs are as efficient as conventional heated humidifiers. HMEFs seem to decrease the rate of nosocomial pneumonia in comparison with heated humidifiers. HMEFs induce a slight increase of dead space which should be taken into consideration during weaning from mechanical ventilation. There are demonstrable data in the literature suggesting the possibility of cross viral infection via the anaesthetic machine when an HMEF is not used. There are no data which suggest a specific type of HMEF regarding viral filtration.
According to the literature data, using an HMEF is essential in anaesthesia and is highly recommended in intensive care.
热湿交换过滤器（HMEF）在临床实践中的应用日益广泛。与此同时，新的科学数据也明确了这些设备的益处。
我们在Medline数据库中检索了所有用英文或法文撰写的论文，不限制发表日期，单独或组合使用以下关键词：湿度、温度、机械通气、设备。
从Medline提供的200篇文章中，我们挑选了直接涉及HMEF的文章。排除了一些较旧的研究以及那些已不再可用的关于HMEF的研究。
对文献中可得的主要数据进行了分析。
机械通气期间，对吸入气体混合物进行加湿和加温是必不可少的。HMEF的性能与气管分泌物的特性之间存在直接联系。这证明了推荐使用每升气体混合物湿度输出高于30毫克水的HMEF是合理的。在这种情况下，HMEF与传统加热加湿器一样有效。与加热加湿器相比，HMEF似乎能降低医院获得性肺炎的发生率。HMEF会导致死腔略有增加，在机械通气撤机期间应予以考虑。文献中有确凿数据表明，不使用HMEF时，存在通过麻醉机发生交叉病毒感染的可能性。没有数据表明哪种特定类型的HMEF具有病毒过滤功能。
根据文献数据，在麻醉中使用HMEF至关重要，在重症监护中强烈推荐使用。
