Evaluation of an end-tidal CO2 detector during cardiopulmonary resuscitation in a canine model for pediatric cardiac arrest
ABSTRACT Our objective was to evaluate a colorimetric end-tidal CO2 detector in a canine model for pediatric cardiac arrest. In a prospective unblinded study, cardiac arrest was induced in 11 anesthetized and paralyzed puppies, weighing 5.0 to 6.1 kg, by clamping the endotracheal tube (ETT) and discontinuing mechanical ventilation. During cardiopulmonary resuscitation (CPR), the detector and the capnometer were connected between the ETT and ventilator tubing. Color shades on the detector ranged from 1 (purple) to 6 (yellow) corresponding to increasing concentrations of CO2. End-tidal CO2 concentrations as indicated by detector color and capnometric reading were monitored and recorded throughout the study. The results showed that there was a significant correlation between the detector color score and capnometric readings (P < 0.001). A sudden rise in end-tidal CO2 indicated by both the capnometer and the detector occurred at return of spontaneous circulation (ROSC) in seven or < 1 minute before ROSC in four animals. This association was significant (P = 0.0009). We conclude that these results demonstrate that, in a canine model for pediatric cardiac arrest, the detector readings correlate with capnometry during CPR and indicate ROSC.
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ABSTRACT: Survival after cardiac arrest occurring outside the hospital averages less than 3 percent. Unfortunately, the outcome of prolonged resuscitative attempts cannot be predicted. End-tidal carbon dioxide levels reflect cardiac output during cardiopulmonary resuscitation. We prospectively determined whether death could be predicted by monitoring end-tidal carbon dioxide during resuscitation after cardiac arrest. We performed a prospective observational study in 150 consecutive victims of cardiac arrest outside the hospital who had electrical activity but no pulse. The patients were intubated and evaluated by mainstream end-tidal carbon dioxide monitoring. Our hypothesis was that an end-tidal carbon dioxide level of 10 mm Hg or less after 20 minutes of standard advanced cardiac life support would predict death. There was no difference in the mean age or initial end-tidal carbon dioxide level between patients who survived to hospital admission (survivors) and those who did not (nonsurvivors). After 20 minutes of advanced cardiac life support, end-tidal carbon dioxide (+/-SD) averaged 4.4+/-2.9 mm Hg in nonsurvivors and 32.8+/-7.4 mm Hg in survivors (P< 0.001). A 20-minute end-tidal carbon dioxide value of 10 mm Hg or less successfully discriminated between the 35 patients who survived to hospital admission and the 115 nonsurvivors. When a 20-minute end-tidal carbon dioxide value of 10 mm Hg or less was used as a screening test to predict death, the sensitivity, specificity, positive predictive value, and negative predictive value were all 100 percent. An end-tidal carbon dioxide level of 10 mm Hg or less measured 20 minutes after the initiation of advanced cardiac life support accurately predicts death in patients with cardiac arrest associated with electrical activity but no pulse. Cardiopulmonary resuscitation may reasonably be terminated in such patients.New England Journal of Medicine 07/1997; 337(5):301-6. DOI:10.1056/NEJM199707313370503 · 54.42 Impact Factor
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ABSTRACT: The performance of a new colorimetric CO2-indicator (Colibri) was assessed in mini-pigs. It performed well during 8-hour procedures. Neither nitrous oxide, nor halothane, nor carbon monoxide, nor intratracheal application of drugs (epinephrine, atropine, lidocaine, and naloxone) interfered with its function. It gave a distinct color change at high ventilation frequencies up to 120/min. The only problem observed was difficulty in matching the colors displayed with the comparison color chart provided. The Colibri's performance seems at least equal to that of the EasyCAP detector, although both devices share some disadvantages (no alarms, semiquantitative, difficult reading in the dark). After initial control of endotracheal tube position by an esophageal detector device, both the Colibri and the EasyCAP seem suited for monitoring of ventilation and circulation if quantitative capnometry is unavailable.American Journal of Emergency Medicine 12/1998; 16(7):677-80. DOI:10.1016/S0735-6757(98)90175-9 · 1.15 Impact Factor
- Pediatric Emergency Care 03/1999; 15(1):64-9. DOI:10.1097/00006565-199902000-00019 · 0.92 Impact Factor