Odegaard Silje, Pillgram Magnus, Berg Nicolas Erlend Vaugelade, Olasveengen Theresa, Kramer-Johansen Jo
Institute for Experimental Medical Research, Ullevål University Hospital, N-0407 Oslo, Norway.
Resuscitation. 2008 Apr;77(1):57-62. doi: 10.1016/j.resuscitation.2007.11.005.
Professional rescuers only deliver chest compressions 39% of the available time before intubation during out-of-hospital cardiac arrest. In manikin-studies lay rescuers need approximately 15s to deliver two ventilations. It is not known how much time professional rescuers use for two ventilations and we hypothesised that the time used for two ventilations with a bag-valve-mask device before tracheal intubation is longer than recommended and that the extended time contributes to the high no flow time.
Quality of CPR was available for analysis in 628 cases of out-of-hospital cardiac arrest in the ambulance service in Oslo, Akershus, London, and Stockholm from 2002 to 2005. The 2000 Guidelines were used as the reference. Ventilations were registered from changes in transthoracic impedance as measured through the standard defibrillation pads. We included episodes only with CPR with a 15:2 pattern for at least 1 min and identified all pauses between chest compressions before intubation.
In the remaining 172 episodes we identified 3097 chest compression pauses. In 1587 (51%) of the pauses we identified two ventilations and a mean pause length for each episode was calculated. The median of these means was 5.5s (IQR; 4.5, 7). These pauses comprised a median 9% (IQR; 4%, 15%) of the time before intubation in these episodes. In 892 (29%) of the pauses we identified a different number of ventilations, or other interventions in addition to ventilation. In the remaining 618 pauses (20%) no ventilations were registered.
Professional rescuers delivered two bag-valve-mask ventilations within the 5-6s as indicated in the 2000 Guidelines, slightly longer than the 3-4s recommended in the 2005 Guidelines. However, only half the pauses were used for two ventilations, and the total time for two ventilations accounted for only 27% of the time without chest compressions. Excessive time for ventilation cannot explain the high no-flow time during CPR by professional rescuers before intubation.
在院外心脏骤停期间，专业救援人员在插管前仅39%的可用时间内进行胸外按压。在人体模型研究中，非专业救援人员进行两次通气大约需要15秒。目前尚不清楚专业救援人员进行两次通气需要多长时间，我们推测在气管插管前使用袋阀面罩装置进行两次通气的时间比推荐时间长，且延长的时间导致了较高的无血流时间。
2002年至2005年期间，在奥斯陆、阿克什胡斯、伦敦和斯德哥尔摩的救护车服务中，有628例院外心脏骤停病例的心肺复苏质量可供分析。以2000年指南作为参考。通过标准除颤电极片测量经胸阻抗的变化来记录通气情况。我们仅纳入至少1分钟采用15:2模式进行心肺复苏的病例，并确定插管前胸外按压之间的所有停顿。
在其余172例病例中，我们识别出3097次胸外按压停顿。在其中1587次（51%）停顿中，我们识别出两次通气，并计算了每次病例的平均停顿时长。这些平均值的中位数为5.5秒（四分位间距；4.5，7）。在这些病例中，这些停顿时间中位数占插管前时间的9%（四分位间距；4%，15%）。在892次（29%）停顿中，我们识别出不同次数的通气，或除通气外的其他干预措施。在其余618次停顿（20%）中未记录到通气情况。
专业救援人员按照2000年指南的指示在5至6秒内进行了两次袋阀面罩通气，略长于2005年指南推荐的3至4秒。然而，只有一半的停顿用于两次通气，两次通气的总时间仅占无胸外按压时间的27%。通气时间过长无法解释专业救援人员在插管前进行心肺复苏期间较高的无血流时间。
