Quality assurance report on the use of continuous positive airway pressure and end-tidal carbon dioxide during respiratory distress in field emergency care

Introduction

The use of continuous positive airway pressure (CPAP) is beneficial in the hospital and home care environment. It is used to support ventilation during neurological disease, ventilatory defects, congestive heart failure and obstructive sleep apnea. Field emergency medicine has inherent complications for the delivery and monitoring of patients receiving CPAP. We completed an internal quality audit to determine whether CPAP had benefit and whether capnography could be comfortably used in parallel with a CPAP device to monitor ventilation.

Methods

The data collection was completed on patients with respiratory distress. Data were collected pre-CPAP and post-CPAP. Patients were monitored with capnography and pulse oximetry. Emergency Medical Services and Emergency Department staff evaluated acceptance and ease of use of the equipment. A one-tailed paired test and descriptive statistics were completed.

Results

Eighteen respiratory distress patients received CPAP: eight female, nine male and one patient had missing data (sex entry was blank). Mean age was 79 years. Statistical significance was determined at P < 0.05. There was no significant difference in heart rate: mean pre-CPAP = 116, mean post-CPAP = 114, P = 0.19. There was a significant improvement in arterial oxygen saturation percentage: pre-CPAP = 81.5, mean post-CPAP = 90.2, P = 0.0003. There was a significant improvement in end-tidal carbon dioxide (etCO₂) (ventilation parameter): mean pre-CPAP = 40.1, mean post-CPAP = 35.1, P = 0.038. There was a significant decrease in respiratory rate: pre-CPAP = 36, post-CPAP = 33, P = 0.031. Using a Borg scale for severity of respiratory distress, there was a significant improvement after CPAP: pre-CPAP = 8.06, post-CPAP = 5.7, P = 0.0001. The emergency medical technicians found the devices, CPAP, mask, and etCO₂, easy to use, and 16 patients ranked it comfortable. Two patients were uncomfortable with CPAP. The most comfortable score was 10; the population scored the overall comfort of CPAP with etCO₂ at 7.8.

Conclusion

CPAP in field emergency medicine can be easily applied, is well tolerated, and results can be monitored by capnography. Capnographic measurements indicated improved ventilation by a decrease in carbon dioxide. CPAP and etCO₂ can be used in field emergencies to support and monitor ventilation during respiratory distress.