Department of Anaesthesiology and Intensive Care Medicine, Ruhr-University Bochum, St. Josef Hospital, Gudrunstraße 56, 44791, Bochum, Germany.
Paediatric Intensive Care Unit, Evelina London Children's Healthcare, Guy's and St. Thomas, NHS, Westminster Bridge Road, SE1 7EH, London, United Kingdom.
J Clin Monit Comput. 2022 Feb;36(1):169-177. doi: 10.1007/s10877-020-00634-4. Epub 2020 Dec 21.
To identify the better volatile anaesthetic delivery system in an intensive care setting, we compared the circle breathing system and two models of reflection systems (AnaConDa™ with a dead space of 100 ml (ACD-100) or 50 ml (ACD-50)). These systems were analysed for the parameters like wash-in, consumption, and wash-out of isoflurane and sevoflurane utilising a test lung model. The test lung was connected to a respirator (circle breathing system: Aisys CS™; ACD-100/50: Puriton Bennett 840). Set parameters were volume-controlled mode, tidal volume-500 ml, respiratory rate-10/min, inspiration time-2 sec, PEEP-5 mbar, and oxygen-21%. Wash-in, consumption, and wash-out were investigated at fresh gas flows of 0.5, 1.0, 2.5, and 5.0 l/min. Anaesthetic target concentrations were 0.5, 1.0, 1.5, 2.0, and 2.5%. Wash-in was slower in ACD-100/-50 compared to the circle breathing system, except for fresh gas flows of 0.5 and 1.0 l/min. The consumption of isoflurane and sevoflurane in ACD-100 and ACD-50 corresponded to the fresh gas flow of 0.5-1.0 l/min in the circle breathing system. Consumption with ACD-50 was higher in comparison to ACD-100, especially at gas concentrations > 1.5%. Wash-out was quicker in ACD-100/-50 than in the circle breathing system at a fresh gas flow of 0.5 l/min, however, it was longer at all the other flow rates. Wash-out was comparable in ACD-100 and ACD-50. Wash-in and wash-out were generally quicker with the circle breathing system than in ACD-100/-50. However, consumption at 0.5 minimum alveolar concentration was comparable at flows of 0.5 and 1.0 l/min.
为了在重症监护环境中确定更好的挥发性麻醉剂输送系统，我们比较了回路呼吸系统和两种反射系统模型（ACD-100 死腔为 100ml 或 ACD-50 死腔为 50ml 的 AnaConDa™）。利用测试肺模型分析了这些系统中异氟醚和七氟醚的吸入、消耗和洗出等参数。测试肺与呼吸机（回路呼吸系统：Aisys CS™；ACD-100/50：Puriton Bennett 840）相连。设定参数为容量控制模式，潮气量 500ml，呼吸频率 10/min，吸气时间 2 秒，呼气末正压 5mbar，氧气 21%。新鲜气体流量分别为 0.5、1.0、2.5 和 5.0l/min 时，进行吸入、消耗和洗出研究。麻醉目标浓度为 0.5、1.0、1.5、2.0 和 2.5%。除了新鲜气体流量为 0.5 和 1.0l/min 时，ACD-100/-50 的吸入速度比回路呼吸系统慢。ACD-100 和 ACD-50 中的异氟醚和七氟醚消耗与回路呼吸系统中新鲜气体流量为 0.5-1.0l/min 时相对应。与 ACD-100 相比，ACD-50 的消耗更高，特别是在气体浓度＞1.5%时。在新鲜气体流量为 0.5l/min 时，ACD-100/-50 的洗出速度比回路呼吸系统快，但在所有其他流速下，洗出时间更长。ACD-100 和 ACD-50 的洗出时间相当。与 ACD-100/-50 相比，回路呼吸系统的吸入和洗出速度通常更快。然而，在新鲜气体流量为 0.5 和 1.0l/min 时，0.5 最低肺泡浓度的消耗相当。
