Sleep disturbances, pain and analgesia in adults hospitalized for burn injuries

BACKGROUND AND PURPOSE: Sleep disturbances are frequently reported in hospitalized patients. We have recently shown significant daily relationships between poor sleep and acute burn pain during the first week of hospitalization, where poor sleep leads to reports of higher pain intensity and in return, greater pain affects quality of sleep. This prospective study was designed to objectively evaluate sleep disturbances in hospitalized burn patients and further evaluate their relationships with pain intensity and administered medication. PATIENTS AND METHODS: Sixteen non-ventilated burn patients wore an actigraph (Ambulatory Monitoring, Inc.) during hospitalization (N of 24-h observations 164). Sleep measures included duration and fragmentation (# of awakenings, mean duration of awakenings, mean duration of sleep episodes (MDAW)). Pain intensity was assessed at rest (nighttime, morning, during the day) and following therapeutic procedures known to be painful (e.g. dressing changes). RESULTS: Although sleep duration was extremely variable, patients slept an average of 5.5 h a night with numerous awakenings. During the day, patients often took naps, bringing their total sleep time (TST) to 8 h. Regression analyses showed significant temporal relationships between sleep, pain and analgesic medication such that a night of poor sleep was followed by a significantly more painful day and higher analgesic intake. Further, high levels of pain and analgesic medication during the day were both significant predictors of poor sleep on the following night. CONCLUSIONS: These results obtained with objective measures support previous findings that subjective sleep quality following burn injuries is poor, and strengthen the evidence of a relationship between sleep and sensitivity to pain. Nonetheless, further analyses are necessary to determine and dissociate the effects of pain intensity and analgesic medication on sleep.