Behavioral changes in brain-injured critical care adults with different levels of consciousness during nociceptive stimulation: an observational study

The primary objective of this study was to describe the frequency of behaviors observed during rest, a non-nociceptive procedure, and a nociceptive procedure in brain-injured intensive care unit (ICU) patients with different levels of consciousness (LOC). Second, it examined the inter-rater reliability and discriminant and concurrent validity of the behavioral checklist used.

The non-nociceptive procedure involved calling the patient and shaking his/her shoulder. The nociceptive procedure involved turning the patient. The frequency of behaviors was recorded using a behavioral checklist.

Patients with absence of movement, or stereotyped flexion or extension responses to a nociceptive stimulus displayed more behaviors during turning (median 5.5, range 0–14) than patients with localized responses (median 4, range 0–10) or able to self-report their pain (median 4, range 0–10). Face flushing, clenched teeth, clenched fist, and tremor were more frequent in patients with absence of movement, or stereotyped responses to a nociceptive stimulus. The reliability of the checklist was supported by a high intra-class correlation coefficient (0.77–0.92), and the internal consistency was acceptable in all three groups (KR 20, 0.71–0.85). Discriminant validity was supported as significantly more behaviors were observed during nociceptive stimulation than at rest. Concurrent validity was confirmed as checklist scores were correlated to the patients’ self-reports of pain (r _s = 0.53; 95 % CI 0.21–0.75).

Brain-injured patients reacted significantly more during a nociceptive stimulus and the number of observed behaviors was higher in patients with a stereotyped response.