Assessing pain in critically ill sedated patients by using a behavioral pain scale

Objective: To establish the validity and reliability of a new behavioral pain scale (BPS) for critically ill sedated adult patients. Design: Prospective evaluation. Setting: Ten-bed trauma and surgical intensive care unit in a university teaching hospital. Patients: Thirty mechanically ventilated patients who were receiving analgesia and sedation. Intervention: Assessments with the BPS were completed consecutively at standardized times (morning, afternoon, night) by pairs of evaluators (nurse and nurse's aide). They collected physiologic parameters and BPS results before and during care procedures: nonnociceptive (group 1, compression stockings application and central venous catheter dressing change), nociceptive (group 2, endotracheal suctioning and mobilization), and retested nociceptive (group 3). The BPS score was the sum of three items that had a range score of 1-4: facial expression, movements of upper limbs, and compliance with mechanical ventilation. Measurements and Main Results: Two hundred and sixty nine assessments were completed, including 104, 134, and 31 measurements in groups 1, 2 and 3, respectively. There was no difference in Ramsay scale scores between the three groups (Ramsay 4-6). Nociceptive stimulations (group 2) resulted in significantly higher BPS values than nonnociceptive ones (group 1, 4.9 vs. 3.5, p < .01), whereas the two groups had comparable BPS values before stimulation (3.1 vs. 3.0). A trend was found in group 2 between the dosage of sedation/analgesia and BPS: the higher the dosage, the lower BPS values and BPS changes to nociceptive stimulation. Group 3 had BPS values similar to group 2 at rest (3.2 vs. 3.2) and during the procedure (4.4 vs. 4.5), with good interrater correlations (r² = .71 and .50, respectively). Conclusions: These results indicate that the expression of pain can be scored validly and reliably by using the BPS in sedated, mechanically ventilated patients. Further studies are warranted regarding the utility of the BPS in making clinical decisions about the use of analgesic drugs in the intensive care unit.