The purpose of this study was to evaluate the use of the conjunctival oxygen tension (PCJO2) monitor during the early assessment of injured patients in the A&E Department of a large District General Hospital. The conjunctival oxygen sensor provides a non-invasive continuous monitor of tissue oxygenation in the palpebral conjunctiva and has been shown to detect early hypovolaemia in animal and human studies. For this preliminary report PCJO2 was recorded with initial clinical findings, standard cardiorespiratory parameters (pulse rate, blood pressure, respiratory rate, Glasgow Coma Score) and final diagnosis. Low PCJO2 (less than 45 mmHg) was associated with hypovolaemia, reduced cardiac output and chest injury. Normal PCJO2 in patients with severe head injury requiring transfer to the Regional Neurosurgical Centre or patients from multivictim road traffic accidents (RTAs) indicated no early occult cardiorespiratory compromise and this was subsequently confirmed. Monitoring PCJO2 seems to provide a valuable adjunct in the initial assessment of the injured patient.