Abstract P64: Synchronized Bag-valve-mask Ventilation With Continuous Chest Compressions Provides Adequate Ventilation During Cardiopulmonary Resuscitation
Background: The traditional approach to non-invasive ventilation during cardiopulmonary resuscitation (CPR) interrupts compressions to deliver bag-valve-mask (BVM) ventilations. This may lead to unnecessary pauses in compressions. It remains unclear as to whether adequate ventilation can be achieved during continuous chest compressions with interposed BVM ventilations.
Objective: To evaluate the effectiveness of synchronous BVM ventilations with continuous chest compressions during CPR.
Methods: A convenience sample of patients suffering OOHCA in an urban EMS system was included. Continuous capnometry was initiated with BVM ventilation. EMS providers performed continuous chest compressions with interposed breaths delivered every 10th compression without pauses. A compression pause for rhythm analysis was performed every 2 minutes. Capnometry, audio recordings, and ECG data were abstracted and analyzed to compare end-tidal CO2 (EtCO2) values immediately before and after intubation as a reflection of ventilation adequacy. To standardize measurements, EtCO2 values were recorded immediately before, during, and after compression pauses for ECG analysis. In addition, post-ROSC EtCO2 values recorded in BVM-ventilated and intubated patients were compared. Finally, aspiration events were abstracted from the agency performance improvement database.
Results: A total of 145 patients were included. Mean ventilation rate was 15.1 breaths/min immediately prior to intubation and 14.9 breaths/min immediately after. EtCO2 values were slightly lower with BVM ventilation vs. intubation immediately before pauses (24.1 vs. 29.5 mmHg), during pauses (21.3 vs. 26.7 mmHg), and immediately after pauses (22.7 vs. 27.2 mmHg). The highest recorded EtCO2 value within 2 minutes of ROSC was 36.7 mmHg in patients undergoing BVM ventilation and 44.2 mmHg in intubated patients. No aspiration events were reported during BVM ventilation.
Conclusions: Synchronous BVM ventilation (10:1 ratio) with continuous chest compressions provided adequate ventilation during CPR as compared with endotracheal intubation. Differences in EtCO2 values can be explained by the increase in dead-space with BVM. Hypercapnea following ROSC was not observed in either cohort.