Objective: We tested the hypothesis that Paco2 would be more tightly controlled if end-tidal CO2 monitoring was used during hand ventilation for transport of intubated patients.
Design: Randomized, prospective analysis of the no-monitor and monitor-blind groups (the monitor was on the bed during transport but only the investigator was aware of the end-tidal CO2 values). Nonrandomized, prospective analysis of the monitor group (ventilation controlled using end-tidal CO2 value from monitor).
Setting: University hospital operating room and intensive care unit (ICU).
Patients: Fifty intubated patients who were transported from the operating room to the ICU or from the ICU to the neuroradiology suite were assigned randomly to one of two groups: a) no-monitor group (n = 25); and b) monitor-blind group (n = 25). An additional group (monitor group, n = 10) was subsequently added to the study.
Interventions: Capnography was instituted in all patients in a blocked fashion.
Measurements and main results: Arterial blood gases and end-tidal CO2 values were measured before and after transport. When comparing overall group data, pre- and post-Paco2 values were similar: monitor 39 +/- 2 vs. 41 +/- 2 torr (5.2 +/- 0.3 vs. 5.5 +/- 0.3 no-monitor 39 +/- 1 vs. 37 +/- torr (5.2 +/- 0.1 vs. 5.0 +/- 0.1 kPa). However, when comparing Paco2 values for individual patients, we found that there was significantly greater variability for Paco2 after transport when end-tidal CO2 was not used for control of ventilation during transport.
Conclusions: These data do not support routine monitoring of end-tidal CO2 during short transport times in adult patients requiring mechanical ventilation. However, the monitor may prevent morbidity in patients requiring tight control of Paco2.