■虽然广泛测量,呼气末二氧化碳(EtCO2)和院外心脏骤停(OHCA)结局之间的时变关联尚不清楚.
■在实用气道复苏试验(PART)中评估EtCO2与自发循环恢复(ROSC)之间的时间关联。
本研究是对复苏结果联盟多中心急诊医疗服务机构进行的整群随机试验的二次分析。PART从2015年12月1日至2017年11月4日纳入了3004名患有非创伤性OHCA的成年人(年龄≥18岁)。2023年6月进行的这项分析有1172例可用的EtCO2。
■PART评估了喉管与气管插管对72小时存活的影响。紧急医疗服务机构使用标准监测器收集连续的EtCO2记录,此二次分析确定了每次通气的最大EtCO2值,并使用先前验证的自动信号处理确定了1分钟时间内的平均EtCO2。包括所有可解释的EtCO2信号大于50%的晚期气道病例。计算EtCO2相对于复苏的变化斜率。
■主要结局是通过院前或急诊科可触及的脉搏确定的ROSC。使用Mann-Whitney检验比较离散时间点的EtCO2值,使用Cochran-Armitage趋势检验比较了EtCO2的时间趋势。进行多变量逻辑回归,根据Utstein标准和EtCO2坡度进行调整。
■在纳入研究的1113名患者中,694(62.4%)为男性;285(25.6%)为黑人或非裔美国人,592(53.2%)为白人,236人(21.2%)是另一个种族;中位年龄(IQR)为64岁(52-75岁).心搏骤停最常见的是没有目击(n=579[52.0%]),不可电击(n=941[84.6%]),和非公开(n=999[89.8%])。有198例(17.8%)有ROSC,915例(82.2%)无ROSC。ROSC和非ROSC病例的中间EtCO2值在10分钟时显著不同(39.8[IQR,27.1-56.4]mmHgvs26.1[IQR,14.9-39.0]mmHg;P<.001)和5分钟(43.0[IQR,28.1-55.8]mmHgvs25.0[IQR,13.3-37.4]mmHg;P<.001)复苏结束前。在ROSC病例中,二氧化碳中位数从30.5增加(IQR,22.4-54.2)mmHG至43.0(IQR,28.1-55.8)mmHg(趋势<.001的P)。在非ROSC案例中,EtCO2从30.8下降(IQR,18.2-43.8)mmHg至22.5(IQR,12.8-35.4)mmHg(趋势<.001的P)。使用具有EtCO2斜率的调整多变量逻辑回归,EtCO2的时间变化与ROSC相关(比值比,1.45[95%CI,1.31-1.61])。
■在对PART试验的二次分析中,EtCO2的时间增加与ROSC几率增加相关.这些结果表明在OHCA复苏期间利用连续波形二氧化碳图的价值。
■ClinicalTrials.gov标识符:NCT02419573。
UNASSIGNED: While widely measured, the time-varying association between exhaled end-tidal carbon dioxide (EtCO2) and out-of-hospital cardiac arrest (OHCA) outcomes is unclear.
UNASSIGNED: To evaluate temporal associations between EtCO2 and return of spontaneous circulation (ROSC) in the Pragmatic Airway Resuscitation Trial (PART).
UNASSIGNED: This study was a secondary analysis of a cluster randomized trial performed at multicenter emergency medical services agencies from the Resuscitation Outcomes Consortium. PART enrolled 3004 adults (aged ≥18 years) with nontraumatic OHCA from December 1, 2015, to November 4, 2017. EtCO2 was available in 1172 cases for this analysis performed in June 2023.
UNASSIGNED: PART evaluated the effect of laryngeal tube vs endotracheal intubation on 72-hour survival. Emergency medical services agencies collected continuous EtCO2 recordings using standard monitors, and this secondary analysis identified maximal EtCO2 values per ventilation and determined mean EtCO2 in 1-minute epochs using previously validated automated signal processing. All advanced airway cases with greater than 50% interpretable EtCO2 signal were included, and the slope of EtCO2 change over resuscitation was calculated.
UNASSIGNED: The primary outcome was ROSC determined by prehospital or emergency department palpable pulses. EtCO2 values were compared at discrete time points using Mann-Whitney test, and temporal trends in EtCO2 were compared using Cochran-Armitage test of trend. Multivariable logistic regression was performed, adjusting for Utstein criteria and EtCO2 slope.
UNASSIGNED: Among 1113 patients included in the study, 694 (62.4%) were male; 285 (25.6%) were Black or African American, 592 (53.2%) were White, and 236 (21.2%) were another race; and the median (IQR) age was 64 (52-75) years. Cardiac arrest was most commonly unwitnessed (n = 579 [52.0%]), nonshockable (n = 941 [84.6%]), and nonpublic (n = 999 [89.8%]). There were 198 patients (17.8%) with ROSC and 915 (82.2%) without ROSC. Median EtCO2 values between ROSC and non-ROSC cases were significantly different at 10 minutes (39.8 [IQR, 27.1-56.4] mm Hg vs 26.1 [IQR, 14.9-39.0] mm Hg; P < .001) and 5 minutes (43.0 [IQR, 28.1-55.8] mm Hg vs 25.0 [IQR, 13.3-37.4] mm Hg; P < .001) prior to end of resuscitation. In ROSC cases, median EtCO2 increased from 30.5 (IQR, 22.4-54.2) mm HG to 43.0 (IQR, 28.1-55.8) mm Hg (P for trend < .001). In non-ROSC cases, EtCO2 declined from 30.8 (IQR, 18.2-43.8) mm Hg to 22.5 (IQR, 12.8-35.4) mm Hg (P for trend < .001). Using adjusted multivariable logistic regression with slope of EtCO2, the temporal change in EtCO2 was associated with ROSC (odds ratio, 1.45 [95% CI, 1.31-1.61]).
UNASSIGNED: In this secondary analysis of the PART trial, temporal increases in EtCO2 were associated with increased odds of ROSC. These results suggest value in leveraging continuous waveform capnography during OHCA resuscitation.
UNASSIGNED: ClinicalTrials.gov Identifier: NCT02419573.