Monitoring the depth of palliative sedation by video-pupillometry: A case report.

Abstract

Palliative sedation is sometimes interrupted by undesired arousals. Pupillometry has been used in anesthesiology to monitor pain and sedation but has never been used during palliative sedation. A 48 years-old patient, with multi-metastatic cancer, underwent palliative sedation to manage global suffering. On the second day, the patient experienced arousal which required medication adjustments to ensure pain relief and increased sedation. Depth of sedation is monitored with clinical scales, such as the Richmond Agitation-Sedation Scale. But these scales do not measure brain stem activity and are poor at predicting arousal. During palliative sedation, an infrared pupillometer was used to monitor pupil size and pupillary reactivity (Neurolight^®, IDMed^®, Marseille, France). The pupillary light reflex was depressed during deep sedation. In our case, we observed a low-normal reflex along with dilated pupil before arousal. Our case suggests that reflex intensity and pupil size might predict arousals during palliative sedation. Prospective studies are needed to confirm our findings. Pupillometry's acceptability should also be questioned from patient's, families', and caregivers' perspectives.