There was a case recently where a paramedic was working a code on a patient in PEA. During the code, the EtCO2 of the patient rose from 12mm to 27. The medic correctly assumed that his patient was a ROSC patient. He stated so to the ED staff when he turned the patient over to them. The doctor ignored the medic, and stated that the increased EtCO2 meant nothing, and declared the patient dead. Some time later, when the staff went in to prepare the patient's body for delivery to the morgue, they noticed the patient trying to breathe. The code was resumed, with the result that the patient finally expired several days later. Lawsuits are pending.
The evidence is overwhelming, capnography is a reliable predictor of ROSC in an arrest patient. Here are some studies to prove my point:
Analysis of the Efficacy of Waveform Capnography Monitoring Using Bag-Valve-Mask Ventilation. Wales, RA. Society for Technology in Anesthesia 2011.
End Tidal Carbon Dioxide Levels Predict Cardiac Arrest. Manyam H. Society for Technology in Anesthesia 2011.
End Tidal Carbon Dioxide Predicts Cardiac Arrest. Manyam H, Thiagarajah P, Patel G, French R, Chaluvadi S, Balaan M. American Heart Association Resuscitation Science Symposium
Analysis of the Efficacy of Waveform Capnography Monitoring Using Bag-Valve-Mask Ventilation. Wales RA, Dyott W. Prehospital Emergency Care (NAEMSP). January 2010; Volume 14, (Suppl 1), 48-49.
Capnography as a Survival Predictor in Cardiopulmonary Resuscitation.Farinha LF. Resuscitation, Volume 81, Issue 2, Supplement 1, December 2010, Page S57.Sleep and Pulmonary Rehab
Partial Pressure of End-tidal Carbon Dioxide – Reliable Criteria for Termination of Non-traumatic Cardiac Arrest Resuscitative Efforts in the Field. Grmec et al. Resuscitation, Volume 81, Issue 2, Supplement 1, December 2010, Page S26.
Capnography during CPR in SUMMA 112: Preliminary Study. Diez-Picazo LD, et al. Congreso Nacional SEMES 2009. June 2009.