Nelskylä Annika, Skrifvars Markus B, Ångerman Susanne, Nurmi Jouni
Department of Emergency Care and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Department of Emergency Care and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
Resuscitation. 2022 Jan;170:276-282. doi: 10.1016/j.resuscitation.2021.10.001. Epub 2021 Oct 9.
High oxygen levels may worsen cardiac arrest reperfusion injury. We determined the incidence of hyperoxia during and immediately after successful cardiopulmonary resuscitation and identified factors associated with intra-arrest cerebral oxygenation measured with near-infrared spectroscopy (NIRS).
A prospective observational study of out-of-hospital cardiac arrest patients treated by a physician-staffed helicopter unit. Collected data included intra-arrest brain regional oxygen saturation (rSO) with NIRS, invasive blood pressures, end-tidal CO (etCO) and arterial blood gas samples. Moderate and severe hyperoxia were defined as arterial oxygen partial pressure (paO) 20.0-39.9 and ≥40 kPa, respectively. Intra-arrest factors correlated with the NIRS value, rSO were assessed with the Spearman's correlation test.
Of 80 recruited patients, 73 (91%) patients had rSO recorded during CPR, and 46 had an intra-arrest paO analysed. ROSC was achieved in 28 patients, of whom 20 had paO analysed. Moderate hyperoxia was seen in one patient during CPR and in four patients (20%, 95% CI 7-42%) after ROSC. None had severe hyperoxia during CPR, and one patient (5%, 95% 0-25%) immediately after ROSC. The rSO during CPR was correlated with intra-arrest systolic (r = 0.28, p < 0.001) and diastolic blood pressure (p = 0.32, p < 0.001) but not with paO (r = 0.13, p = 0.41), paCO (r = 0.18, p = 0.22) or etCO (r = 0.008, p = 0.9).
Hyperoxia during or immediately after CPR is rare in patients treated by physician-staffed helicopter units. Cerebral oxygenation during CPR appears more dependent, albeit weakly, on hemodynamics than arterial oxygen concentration.
高氧水平可能会加重心脏骤停再灌注损伤。我们确定了成功实施心肺复苏期间及之后即刻高氧血症的发生率，并识别出与通过近红外光谱法（NIRS）测量的心脏骤停期间脑氧合相关的因素。
对由配备医生的直升机急救单元治疗的院外心脏骤停患者进行一项前瞻性观察性研究。收集的数据包括通过NIRS测量的心脏骤停期间脑局部氧饱和度（rSO）、有创血压、呼气末二氧化碳分压（etCO）以及动脉血气样本。中度和重度高氧血症分别定义为动脉血氧分压（paO）为20.0 - 39.9kPa和≥40kPa。使用Spearman相关性检验评估与NIRS值rSO相关的心脏骤停期间因素。
在80例纳入研究的患者中，73例（91%）患者在心肺复苏期间记录了rSO，46例患者分析了心脏骤停期间的paO。28例患者实现了自主循环恢复（ROSC），其中20例分析了paO。在心肺复苏期间有1例患者出现中度高氧血症，在自主循环恢复后有4例患者（20%，95%CI 7 - 42%）出现中度高氧血症。在心肺复苏期间无患者出现重度高氧血症，在自主循环恢复后即刻有1例患者（5%，95% 0 - 25%）出现重度高氧血症。心肺复苏期间的rSO与心脏骤停期间的收缩压（r = 0.28，p < 0.001）和舒张压（p = 0.32，p < 0.001）相关，但与paO（r = 0.13，p = 0.41）、paCO（r = 0.18，p = 0.22）或etCO（r = 0.008，p = 0.9）无关。
在由配备医生的直升机急救单元治疗的患者中，心肺复苏期间或之后即刻出现高氧血症的情况很少见。心肺复苏期间的脑氧合似乎更多地依赖于血流动力学，尽管这种依赖较弱，而非动脉氧浓度。
