Predictors of severe pain in the immediate postoperative period in elderly patients following hip fracture surgery

Introduction

The aim of this study was to identify risk factors for severe postoperative pain immediately after hip-fracture surgery.

Patients and methods

Three hundred forty-four elderly patients with an acute hip fracture were admitted to the hospital during a 12-months period. All patients who entered the study answered a structured questionnaire to assess demographic characteristics, previous diseases, drug use, previous surgery, and level of education. Physical status was assessed through the American Society of Anesthesiologists’ preoperative risk classification, cognitive status using the Short Portable Mental Status Questionnaire, and depression using the Geriatric Depression Scale. The presence of preoperative delirium using the Confusion Assessment Method was assessed during day and night shifts until surgery. Pain was measured using a numeric rating scale (NRS). An NRS ≥7 one hour after surgery indicated severe pain.

Results

Patients with elementary-level education (8 yr in school) presented a higher risk for immediate severe postoperative pain than university-educated patients (>12 yr in school) (P < 0.05). Higher cognitive function was associated with higher postoperative pain (P < 0.01). Patients with symptoms of depression and patients with preoperative delirium presented a higher risk for severe pain (P < 0.05, P < 0.01, respectively). Multivariate analysis showed that depression and a low level of education were independent predictors of severe pain immediately after surgery.

Conclusion

Depression and lower levels of education were independent predictors of immediate severe pain following hip-fracture surgery. These predictors could be clinically used to stratify analgesic risk in elderly patients for more aggressive pain treatment immediately after surgery.