The sixth vital sign: end-tidal CO2 in pediatric trauma patients during transport

Transport of pediatric trauma victims, within as well as between medical centers, has become a frequent event and an integral activity of pediatric critical care units. Monitoring patients during transport is of utmost importance, as an unstable environment poses an increased threat to the patient's stability. The level of monitoring and care should approximate that of the critical care unit. Monitoring end-tidal CO2 (EtCO2) has become routine for many pediatric intensive care unit patients but technical problems have limited its use during transport. Our transport team uses a transportable EtCO2 monitor of the side-stream type (NPB 75), requiring very small samples; midstream sampling overcomes humidity interference. The monitor is small and lightweight, operates on a rechargeable battery and is especially designed for the demanding environment of transport. From October 1997 through January 1999, 187 pediatric patients, 62 of whom were trauma victims, were transported for a total of 45 hours, including 2 hours of in-flight transport. Age range was 3 months to 16 years. Of the 53 monitored for EtCO2, in 9 (17%) monitoring resulted in a significant, immediate change of treatment during transport. We find EtCO2 an important adjunct in monitoring pediatric trauma patients during transport. In addition to conventional monitoring of heart rate, blood pressure, respiratory rate, body temperature and blood oxygen saturation, we suggest EtCO2 as the sixth vital sign that should be monitored.