Behavioral pain scales, vital signs, and pupilometry to pain assessment in the critically ill patient: A cross sectional study.

BACKGROUND

Detecting pain in sedated critically ill patients requires utmost attention.

AIM

To assess the pain in mechanically ventilated critically ill patients with the Behavioral Pain Scale (BPS), Behavioral Indicators Pain Scale (ESCID), the pupillary dilation response (PDR), and vital signs.

DESIGN

Cross-sectional study METHODS: The study was conducted between March and December 2019, involving patients with a baseline BPS of 3, ESCID of 0, and RASS between -1 and -4. Patients with mobility limitations or altered pupillary reflexes were excluded. We measured before and after non-painful stimulation (NP) followed by 10-20-30-40 mA stimuli and endotracheal aspirate (ETA). The primary outcome was the pain measured with BPS and ESCID scales and PDR with AlgiScan® pupilometer defined as BPS≥4, ESCID≥1, and PDR≥11,5 %. We performed a descriptive study and analyzed the agreement between pain detection methods.

RESULTS

Thirty-one patients were included, and 183 measurements were recorded. The scales showed minimal changes. Approximately 30 % of patients reported pain at a 30 mA stimulus, increasing to over 70 % after ETA. The PDR ranged from 2 % to 6-33% on the ETA, even in pain-free patients, with pain incidence between 70 % and 100 % for the 40 mA and ETA stimuli. Vital signs did not show relevant changes. The PDR had over 90 % agreement with scales for no pain. For higher-intensity stimuli, agreement ranged from 60 % to 80 %. Disagreement occurred when there was no pain by scales (BPS<4; ESCID<1) and pain with PDR (PDR≥11.5).

CONCLUSIONS

Pain behavioral scores and vital signs were low in critically ill patients. PDR detected a nociceptive pain response in no-pain patients.