Emergency and Critical Care Medicine, Tokushima University Hospital, Tokushima, Japan.
Emergency and Disaster Medicine, Tokushima University Hospital, Tokushima, Japan.
Respir Care. 2019 Feb;64(2):130-135. doi: 10.4187/respcare.06294. Epub 2018 Sep 25.
Most heat-and-moisture exchangers (HMEs) for patients with tracheostomy and spontaneously breathing are small and have suction ports that allow some expiratory gas to escape, which loses water vapor held in the expired gas. Recently, a heated-and-humidified high-flow system for spontaneously breathing patients with tracheostomy was developed. Little is known, however, about the humidifying performance of HMEs or heated-and-humidified high-flow systems for spontaneous breathing patients with a tracheostomy.
To investigate the humidifying performance of the HMEs and heated-and-humidified high-flow systems for spontaneously breathing patients with tracheostomy.
Adult spontaneously breathing subjects with tracheostomy and were enrolled when their respiratory parameters and S were stable. We measured absolute humidity, relative humidity, and temperature by using a capacitance-type moisture sensor at the outlet of the tracheostomy tube. Heated-and-humidified high flow was delivered via the a humidifier and tracheostomy interface, and a selected HME. The subjects received heated-and-humidified high flow, after which an HME was used for humidification before switching back to a heated-and-humidified high-flow system.
Ten subjects (5 men, 5 women; mean ± SD age, 72 ± 12 y) were enrolled. The admission diagnoses were neurologic (5 subjects), respiratory failure (3), and cardiac arrest (2). The APACHE (Acute Physiology and Chronic Health Evaluation) II score was 24 (interquartile range, 20-27). Tracheostomy was performed on day 7 (interquartile range, 5-11 d) after endotracheal intubation, and the duration of mechanical ventilation was 10 d (interquartile range, 6-11 d). The temperature with the HME was 29.9 ± 1.0°C and, during heated-and-humidified high-flow use was 35.3 ± 0.8°C ( < .001). With both the HME and the heated-and-humidified high-flow system, the relative humidity reached 100%; the absolute humidity with HME was 30.2 ± 1.8 mg/L, and, with the heated-and-humidified high-flow system, was 40.3 ± 1.8 mg/L ( < .001).
In spontaneously breathing subjects with tracheostomy, an heated-and-humidified high-flow system achieved higher absolute humidity than did an HME.
大多数用于气管切开和自主呼吸患者的热湿交换器（HME）体积较小，并且具有吸气口，这会导致一些呼出气体逸出，从而失去呼出气体中所含的水蒸气。最近，为气管切开的自主呼吸患者开发了一种加热和加湿的高流量系统。但是，对于气管切开的自主呼吸患者，HME 或加热和加湿高流量系统的加湿性能知之甚少。
研究 HME 和加热加湿高流量系统对气管切开的自主呼吸患者的加湿性能。
当患者的呼吸参数和 S 稳定时，纳入成年自主呼吸的气管切开患者。我们使用电容式湿度传感器测量气管切开管出口处的绝对湿度、相对湿度和温度。加热和加湿的高流量通过加湿器和气管切开接口输送，然后使用选定的 HME。在切换回加热加湿高流量系统之前，先使用 HME 进行加湿。
纳入 10 名患者（5 名男性，5 名女性；平均年龄 ± 标准差为 72 ± 12 岁）。入院诊断为神经疾病（5 例）、呼吸衰竭（3 例）和心搏骤停（2 例）。急性生理学和慢性健康评估（APACHE）II 评分 24（四分位间距 20-27）。气管切开术在气管插管后第 7 天（四分位间距 5-11 天）进行，机械通气时间为 10 天（四分位间距 6-11 天）。HME 时的温度为 29.9 ± 1.0°C，使用加热加湿高流量时为 35.3 ± 0.8°C（<.001）。使用 HME 和加热加湿高流量系统时，相对湿度均达到 100%；HME 的绝对湿度为 30.2 ± 1.8 mg/L，加热加湿高流量系统的绝对湿度为 40.3 ± 1.8 mg/L（<.001）。
在气管切开的自主呼吸患者中，加热加湿高流量系统的绝对湿度高于 HME。
