Recalled pain scores are not reliable after acute trauma

Pain research in emergency settings can be problematic, as data collection is logistically difficult and pain levels are often poorly documented. Short-term recall of acute pain has been evaluated in postoperative, labour and procedural pain, with variable reported accuracy. The reliability of pain recall in trauma resuscitation patients is unknown. This study aims to determine the accuracy of short-term pain recall 1-2 days after trauma.

Prospective, cohort study of trauma resuscitation patients transported by ambulance to a major trauma centre. Patients with haemodynamic instability (SBP<90, HR>120) or GCS<14 on arrival were excluded. Momentary pain scores were measured on an 11-point verbal numerical rating scale by paramedics during prehospital management. Patients were evaluated within 48 h of injury on the recall of their initial pain, pain during transport, and lowest pain score achieved by prehospital analgesia. Spearman's rank correlation and Bland-Altman tests were used to compare ambulance and hospital data.

88 trauma resuscitation patients (mean age 44 years ± 18 SD, male 74%, mean ISS: 7 ± 5 SD) were enrolled over a 5 month study period. Comparison of immediate and recalled pain scores produced Spearman's correlation coefficients of 0.71 for initial pain, 0.56 for pain during transport, and 0.45 for minimum pain scores.

In our study patients did not accurately recall their pain levels 1-2 days after acute trauma. The results suggest that retrospective pain ratings are not reliable in trauma patients.