Effects of continuous flow insufflation of oxygen on arterial gazometry during cardiopulmonary resuscitation

Introduction

During experimental cardiac arrrest, precordial compression associated to the unique use for ventilation of constant flow insufflation of air at the distal end of a modified endotracheal tube provided the same ventilatory results but better hemodynamic effects than manual ventilation [1]. Because of these results and the simplicity of the technique, a study concerning humans beings and using oxygen during cardiopulmonary resuscitation (CPR) has been realized.

Methods

After ethic committee approval, adult out-of-hospital cardiac arrests (shocked arrests excluded) were randomized in two groups: control group (C) treated by conventional CPR with active compression-decompression (ACD) and manual ventilation after intubation. Constant Flow Insufflation group (CFI-CPR) treated with ACD and flow rate of 15 l/min through small capillaries of Boussignac tube (Vygon, Ecouen, France). CPR continued for 30 min at the most. As soon as spontaneous circulation returned (SCR), arterial gazometry was made and all patients were mechanically ventilated. Statistical analysis was performed by ?₂ and Mann-Whitney tests. A P < 0.05 was considered statistically significant. Results were expressed as mean ± SD.

Results

Thirty patients were included in C group, 34 in CFI-CPR group. There were no differences in mean age (65 ± 3 vs 62 ± 3 years) or delayed CPR activation (6 ± 2 vs 7 ± 3 min). SCR was observed in 8 patients of C group after 13 ± 6 min and in 6 patients of CFI-CPR group after 14 ± 6 min (NS). The results of arterial gazometries for both group are shown in the Table.

Conclusion

Comparable values of arterial gazometry were observed after CFI-CPR or standard CPR. This easier technique is as efficient as manual ventilation in terms of oxygenation during the early phase of cardiac arrest. Further studies are required to determine if CFI-CPR improve prognosis.

Table 1