Mechanical chest compression devices in 30:2 mode provide 3-second pauses to allow for two insufflations. We aimed to determine how often two insufflations are provided in these ventilation pauses, in order to assess if prehospital providers are able to ventilate out-of-hospital cardiac arrest (OHCA) patients successfully during mechanical chest compressions. Data from OHCA cases of the regional ambulance service of Utrecht, The Netherlands, were prospectively collected in the UTrecht studygroup for OPtimal registry of cardIAc arrest database (UTOPIA). Compression pauses and insufflations were visualized on thoracic impedance and waveform capnography signals recorded by manual defibrillators. Ventilation pauses were analyzed for number of insufflations, duration of the subintervals of the ventilation cycles, and ratio of successfully providing two insufflations over the course of the resuscitation. Generalized linear mixed effects models were used to accurately estimate proportions and means. In 250 cases, 8473 ventilation pauses were identified, of which 4305 (51%) included two insufflations. When corrected for non-independence of the data across repeated measures within the same subjects with a mixed effects analysis, two insufflations were successfully provided in 45% of ventilation pauses (95% CI: 40–50%). In 19% (95% CI: 16–22%) none were given. Providing two insufflations during pauses in mechanical chest compressions is mostly unsuccessful. We recommend developing strategies to improve giving insufflations when using mechanical chest compression devices. Increasing the pause duration might help to improve insufflation success.

中文翻译：

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机械胸外按压心肺复苏期间的通气：在 3 秒通气暂停期间进行两次吹气的频率是多少？


30:2 模式下的机械胸部按压设备可提供 3 秒的暂停，以便进行两次吹气。我们的目的是确定在这些通气暂停期间提供两次吹气的频率，以评估院前提供者是否能够在机械胸外按压期间成功为院外心脏骤停 (OHCA) 患者进行通气。荷兰乌得勒支地区救护车服务中心的 OHCA 病例数据由 UTrecht 研究组前瞻性收集，用于心脏骤停数据库 (UTOPIA) 的 OPtimal 登记。按压暂停和充气通过手动除颤器记录的胸廓阻抗和波形二氧化碳图信号进行可视化。分析通气暂停的吹气次数、通气周期子间隔的持续时间以及在复苏过程中成功提供两次吹气的比率。使用广义线性混合效应模型来准确估计比例和平均值。在 250 例病例中，发现了 8473 次通气暂停，其中 4305 例（51%）包括两次吹气。当通过混合效应分析对同一受试者重复测量数据的非独立性进行校正时，在 45% 的通气暂停中成功进行了两次吹气（95% CI：40-50%）。 19%（95% CI：16-22%）没有给予任何治疗。在机械胸外按压暂停期间提供两次吹气大多是不成功的。我们建议制定策略来改善使用机械胸部按压设备时的充气。增加暂停持续时间可能有助于提高吹气成功率。