Partial pressure of end-tidal carbon dioxide successful predicts cardiopulmonary resuscitation in the field: a prospective observational study

Abstract

Introduction Prognosis in patients suffering out-of-hospital cardiac arrest is poor. Higher survival rates have been observed only in patients with ventricular fibrillation who were fortunate enough to have basic and advanced life support initiated soon after cardiac arrest. An ability to predict cardiac arrest outcomes would be useful for resuscitation. Changes in expired end-tidal carbon dioxide levels during cardiopulmonary resuscitation (CPR) may be a useful, noninvasive predictor of successful resuscitation and survival from cardiac arrest, and could help in determining when to cease CPR efforts. Methods This is a prospective, observational study of 737 cases of out-of-hospital cardiac arrest. The patients were intubated and measurements of end-tidal carbon dioxide taken. Data according to the Utstein criteria, demographic information, medical data, and partial pressure of end-tidal carbon dioxide (Pet CO 2 ) values were collected for each patient in cardiac arrest by the emergency physician. We hypothesized that an end-tidal carbon dioxide level of 1.9 kPa (14.3 mmHg) or more after 20 minutes of standard advanced cardiac life support would predict restoration of spontaneous circulation (ROSC). Results Pet CO 2 after 20 minutes of advanced life support averaged 0.92 ± 0.29 kPa (6.9 ± 2.2 mmHg) in patients who did not have ROSC and 4.36 ± 1.11 kPa (32.8 ± 9.1 mmHg) in those who did ( P < 0.001). End-tidal carbon dioxide values of 1.9 kPa (14.3 mmHg) or less discriminated between the 402 patients with ROSC and 335 patients without. When a 20-minute end-tidal carbon dioxide value of 1.9 kPa (14.3 mmHg) or less was used as a screening test to predict ROSC, the sensitivity, specificity, positive predictive value, and negative predictive value were all 100%. Conclusions End-tidal carbon dioxide levels of more than 1.9 kPa (14.3 mmHg) after 20 minutes may be used to predict ROSC with accuracy. End-tidal carbon dioxide levels should be monitored during CPR and considered a useful prognostic value for determining the outcome of resuscitative efforts and when to cease CPR in the field.

Asphyxial cardiac arrest, resuscitation and neurological outcome in a Landrace/Large-White swine model

“…Studies have confirmed that the measurement of ETCO 2 is predictive of the outcomes of CPR. 56,60 Human studies have suggested that ETCO 2 correlates closely with successful resuscitation and predicts the outcome of CA reliably 61,62 The initial ETCO 2 immediately after unclamping the ETT did not correlate with ROSC in the present study. This has already been described in previous animal studies.…”

Part 8: Advanced Life Support

“…Eleven studies showed that physiological monitoring values (ETCO 2 , coronary perfusion pressure, venous oxygen saturation) increased when ROSC was achieved (LOE 4) [171][172][173][174][175][176][177][178]135,179,180 and that they may be an indication of ROSC before it can be seen in vital signs. 181 Five of the studies found that ETCO 2 was accurate for predicting patients who could not be resuscitated; some gave a time frame for that prediction of 20 minutes (LOE 4).…”

“…181 Five of the studies found that ETCO 2 was accurate for predicting patients who could not be resuscitated; some gave a time frame for that prediction of 20 minutes (LOE 4). 136,174,178,182,183 However, 2 studies documented patients who did not meet the ETCO 2 range but who survived (LOE 4). 174,184 Multiple studies by 1 group (LOE 4) [175][176][177] showed that when ETCO 2 exceeded 10 mm Hg, all patients achieved ROSC.…”

Monitoring Dead Space in Mechanically Ventilated Children: Volumetric Capnography Versus Time-Based Capnography

“…For this reason, capnography is now recommended in cardiopulmonary resuscitation to detect the return of spontaneous circulation by identifying resuming pulmonary perfusion. 30 Our study has some important limitations. Respiratory therapists actively involved in caring for children rather than research staff recorded the data.…”