PATIENT-CONTROLLED ANALGESIA WITH NITROUS-OXIDE IN CANCER PAIN

We tested a new nitrous oxide (N2O) delivery system to explore its use fulness in patient-controlled analgesia. Six patients with uncontrolle d cancer-related pain were studied. Patients could give themselves inh alations of a fixed 50%/50% mixture of N2O and oxygen via mouthpiece o r face mask. This therapy supplemented other available modalities, pri ncipally long-acting oral morphine. We found this strategy to be envir onmentally safe, well accepted by patients and staff and effective in relieving pain. Ambient concentrations of N2O were measured and sugges ted that environmental exposure to caregivers was minimal and safe. No problems were encountered with family and staff acceptance of this mo dality. We suggest that this method may be a useful addition to pain c ontrol measures in cancer patients, and merits further study.