Cerebral oxygenation monitoring during resuscitation by emergency medical technicians: a prospective multicenter observational study

Abstract

To assess the feasibility and predictive ability of regional cerebral oxygen saturation monitoring during cardiopulmonary resuscitation by emergency medical technicians. Methods: This prospective observational study included 33 cardiac arrest patients who received cardiopulmonary resuscitation in a prehospital setting. Patients were connected to a near-infrared spectrometer through two disposable probes immediately after entering the ambulance. The monitor, which showed regional cerebral oxygen saturation readings, was obscured by covering it with a sheet of paper. Regional cerebral oxygen saturation was measured continuously until hospital arrival. Outcome variables included the prehospital return of spontaneous circulation, survival to hospital admission, and survival at 90 days. Results: For patients who survived >90 days after hospital admission (n = 2), the mean regional cerebral oxygen saturation values upon ambulance and hospital arrival were 24% and 60%, respectively; for patients who did not survive (n = 31), the mean regional cerebral oxygen saturation values were 15% and 17%, respectively. Regional cerebral oxygen saturation values increased to a greater extent between ambulance arrival and hospital arrival in patients who survived >90 days (median, 36%; interquartile range, 32-40%) than in those who did not survive (0; 0-6%; P = 0.07). Additionally, regional cerebral oxygen saturation values were not related to the prehospital return of spontaneous circulation or survival to hospital admission. Conclusion: Regional cerebral oxygen saturation could be monitored during resuscitation by emergency medical technicians, and it can be used during physiological monitor-guided cardiopulmonary resuscitation.

Comments on “Cerebral oxygenation monitoring during resuscitation by emergency medical technicians: a prospective multicenter observational study”

“…Conflict of interest: None. Shunichiro Nakao, 1 Tomoya Hirose, 1 Mitsuo Ohnishi, 2 and Tadahiko Shiozaki 1…”

“…Dear Editor, We read with interest the recently published article by Hamanaka et al 1 These authors reported that the increase in regional cerebral oxygen saturation (rSO 2 ) during cardiopulmonary resuscitation (CPR) monitored by emergency medical technicians (EMTs) was higher in patients who survived more than 90 days than those who did not, although the increase was not statistically significant. We would like to discuss three issues from their article regarding their methodology, an illogical leap in the conclusions, and an insufficient literature search.…”

“…1 Moreover, their table 2 indicates that one patient achieved prehospital return of spontaneous circulation with a peak rSO 2 of 15%. 1 We assume that they substituted 15% for the unmeasurable value of rSO 2 as per their previous report. 2 However, in our prehospital study of patients with out-of-hospital cardiac arrest, we did not observe initial cerebral rSO 2 values of 15% or lower at the beginning of the measurement.…”

“…According to their table 1 showing the first quartile of peak rSO 2 to be 15%, at least 9 of the 33 enrolled patients had a peak rSO 2 of 15%, that is, their rSO 2 values remained flat as the lower limit of detection of their device was 15% 1 . Moreover, their table 2 indicates that one patient achieved prehospital return of spontaneous circulation with a peak rSO 2 of 15% 1 . We assume that they substituted 15% for the unmeasurable value of rSO 2 as per their previous report 2 .…”