Conjunctival oxygen tension monitoring during helicopter transport of critically ill patients.

To investigate the utility of conjunctival oxygen tension measurement during helicopter transport, we monitored conjunctival oxygen tension (PcjO2) in 36 clinically unstable patients. Sixteen (44%) of the patients were found to have ventilatory or circulatory compromise as determined by PcjO2 less than 50 torr. In only three of these patients would vital sign determinations have detected the unstable clinical states. In 12 patients (33%), respiratory intervention or expansion of intravascular volume resulted in improvement of tissue oxygenation and clinical state. These results demonstrate that a substantial fraction of our patients transported by helicopter had underlying physiologic abnormalities that were not apparent by monitoring of vital signs, but were detected and corrected by measurement of conjunctival oxygen tension.