Quality of CPR has little impact on cerebral oximetry during in-hospital cardiac arrest – preliminary data from three case reports

Introduction

The quality of CPR is associated with survival [1]. The goal of CPR is to provide sufficient cerebral blood flow (CBF). This prospective and observational study was planned to evaluate if the quality of CPR is correlated to a surrogate marker for CBF as estimated by regional cerebrovascular oxygen saturation (rSO2).

Methods

As a preliminary report, a case series of three cardiac arrest patients is presented herein. We used a defibrillator with a quality CPR-technology (Philips, HeartStart MRx Q-CPR™), which evaluates resuscitation from compression to compression. rSO₂ was assessed simultaneously with a near-infrared spectroscopy device (Invos, Somanetics, Troy, MI).

Results

Case 1

75 years old male was resuscitated from asystole. The average compression frequency was 96/min and depth 56 mm. Only 1% of compressions were committed with incomplete release from chest and flow time was 100%. The values for rSO2 were 15–18%, and quality of CPR showed no reflections to rSO2. A minor increase of rSO2 was observed after ROSC.

Case 2

81 years old female was resuscitated from PEA. Compression frequency was 103/min and depth 53 mm, 1% with incomplete release, and flow time 84%. There was an almost immediate increase in rSO2 from 25% to 38%. She achieved ROSC after 11 min where after rSO2 rose to 67%. This patient is a secondary survivor.

Case 3

72-yr old female was resuscitated 17 min from asystole. Average compression frequency was 109/min, and depth 44 mm. 93% of compressions were adequate in depth but 10% of had an incomplete release. Flow time was 90%. During the entire procedure the rSO2 was 15%, despite the relatively good quality of CPR. No ROSC was achieved.

Conclusion

The only survivor had markedly higher rSO2 values than the non-survivors but, on the average, there was no correlation between the quality of CPR and rSO2. Other factors than just the quality of CPR are obviously of major importance for the restoration of cerebral blood flow.