Femoral nerve block in a representative sample of elderly people with hip fracture: A randomised controlled trial

Abstract

Introduction: The number of elderly people with hip fracture and dementia is increasing, and many of these patients suffer from pain. Opioids are difficult to adjust and side effects are common, especially with increased age and among patients with dementia. Preoperative femoral nerve block is an alternative pain treatment.

Aim: To investigate whether preoperative femoral nerve block reduced acute pain and opioid use after hip fracture among elderly patients, including those with dementia.

Patients and methods: In this randomised controlled trial involving patients aged ≥70years with hip fracture (trochanteric and cervical), including those with dementia, we compared femoral nerve block with conventional pain management, with opioid use if required. The primary outcome was preoperative pain, measured at five timepoints using a visual analogue scale (VAS). Preoperative opioid consumption was also registered.

Results: The study sample comprised 266 patients admitted consecutively to the Orthopaedic Ward. The mean age was 84.1 (±6.9)years, 64% of participants were women, 44% lived in residential care facilities, and 120 (45.1%) had dementia diagnoses. Patients receiving femoral nerve block had significantly lower self-rated pain scores from baseline to 12h after admission than did controls. Self-rated and proxy VAS pain scores decreased significantly in these patients from baseline to 12h compared with controls (p<0.001 and p=0.003, respectively). Patients receiving femoral nerve block required less opioids than did controls, overall (2.3±4.0 vs. 5.7±5.2mg, p<0.001) and in the subgroup with dementia (2.1±3.3 vs. 5.8±5.0mg, p<0.001).

Conclusion: Patients with hip fracture, including those with dementia, who received femoral nerve block had lower pain scores and required less opioids before surgery compared with those receiving conventional pain management. Femoral nerve block seems to be a feasible pain treatment for elderly people, including those with dementia.

Keywords: Dementia; Femoral neck fracture; Femoral nerve block; Frail elderly; Hip fracture; Opioid; Pain; Preoperative period.