◊ BACKGROUND:
Post-operatively, elderly patients with impaired vision and cognitive dysfunction may experience difficulties understanding standard pain assessment tools such as the 10-cm Visual Analogue Scale (VAS) and the Verbal Rating Scale (VRS). Thus, there is a need to identify more feasible post-operative pain assessments for elderly patients. With this goal in mind, we compared the VAS and VRS with two more expressive tools: the 50-cm Red Wedge Scale (RWS) and the Facial Pain Scale (FPS). Methods: Cardiac surgery patients (73 ± 5 years, mean ± SD) were allocated to an RWS (n=80) or an FPS (n=80) group. Pain was assessed at rest and after movement during the first 4 days after tracheal extubation. The RWS or FPS assessments were repeated after 10 min. All patients completed the VRS and VAS. Results: The rates of successful pain measurement on study day 1 were: VRS 86%, VAS 62%, RWS 78%, and FPS 60%. Pain measurements with the RWS correlated with the VAS (r=0.758, P<0.001) and weaker with the VRS (r=0.666, P<0.001) measurements. Pain measurements with the FPS correlated well with the VAS (r=0.873, P<0.001) and weaker with the VRS (r=0.583, P<0.001) measurements. With all scales, success rates improved during the study period. Conclusion: In elderly patients, immediately after cardiac surgery, the VRS is the most feasible pain scale, followed by the RWS. The traditional 10-cm VAS is unsuitable for pain measurement in this population.

◊ Reviewed by S. Schug, MD, PhD
Chair of Anaesthesiology,
Pharmacology and Anaesthesiology Unit, Royal Perth Hospital, Perth, Australia

This study addresses the important, but difficult issue of assessing postoperative pain in elderly, often visually and cognitively impaired patients. There is widespread and well-founded concern that poor assessment of pain in this group of patients may lead to insufficient treatment with analgesics, in particular in the postoperative period, but also in chronic pain settings. It is therefore commendable, that another study looked at this important issue.

Not surprisingly, the authors found, that pain assessment with any scale was most difficult at the first postoperative day, when impairment of vulnerable patients is highest. The authors also found a simple verbal rating scale to be most feasible in this population. These findings are in line with a series of similar studies consistently showing the superiority of verbal rating scales in cognitively impaired patients.

Findings are also valid for the chronic pain setting, where the Australian Pain Society suggested replacing the numerical by verbal rating scales in the widely used Brief Pain Inventory (BPI). The resulting Residents’ Verbal Brief Pain Inventory (RVBPI) is more applicable for the use in Residential Aged Care Facilities.

In conclusion, there is now high level evidence, that the assessment of acute and chronic pain intensity in elderly patients with visual and/or cognitive impairment is most successful with the use of a Verbal Rating Scale.