Describing and predicting the nature of procedural pain after thermal injuries: implications for research.

A prerequisite for studying and treating burn-related pain is the establishment of a good understanding of the nature of burn-related pain. However, in most investigations of pain, researchers have failed to examine pain over time or to create summary scores that capture differences in the nature of the pain experiences of individual patients. For 10 consecutive days, 47 patients treated for burn injuries reported on three aspects of procedural pain: worst pain, sensory pain, and affective pain. Three summary pain scores were constructed for each pain dimension: average pain, variability in pain, and linear change in pain. The authors found considerable variability in pain reports from the same patient and from different patients. Analyses indicated that pain reports decreased over time and that patients who had more trait anxiety reported more pain. Patients with larger burn injuries tended to report more affective pain and tended to have a pattern of high and low pain reports that differed from patients with less severe burn injuries. These findings suggest that adequate assessment of burn pain must occur frequently over the course of a single day, as well as for the duration of each patient's care.