PENG Block for Patients Undergoing Neck of Femur (NOF) Fracture Surgery: a Dose Finding Study

Neck of femur (NOF) fracture is a common presentation to the emergency department, particularly in the older population. 77,210 NOF fractures were recorded in the UK and Ireland in 2018 and the number of cases is projected to increase as life expectancy improves. NOF fracture is associated with a high social and economic cost, estimated to cost €45 million annually in Ireland with significant effects on patients' quality of life

The latest Irish Hip Fracture Database (IHFD) report from 2019 detailed 3,701 NOF fractures in patients over 60 years of age in Ireland. These patients occupied 72,314 acute hospital bed days nationally and 437 of these patients attended CUH. This frail and vulnerable group had an average age of 81 and many people suffered numerous co-morbid conditions. This population of patients is therefore at significant risk of complications and require multidisciplinary input to optimise clinical outcome

From a patient's perspective, NOF fracture is a very painful condition, requiring early surgical fixation. It is associated with significant morbidity and mortality. The 30-day mortality for this condition has improved recently. This has likely multifactorial, in part due to the introduction of clinical guidelines, national audits, a focus on processes and changes in how hip fracture care is funded. However, 5% of patients who sustained a hip fracture in Ireland in 2019 died. An additional 4% of patients required new admission to a nursing home following this fracture and a further 13% required convalescent care.

These patients are also particularly at risk for under treatment of pain. Contraindications to many commonly used analgesics such as non-steroidal anti-inflammatory drugs (NSAIDs) exist in this population, including renal dysfunction in 40%. Older adults suffer more adverse effects from opiate analgesia such as nausea, vomiting, constipation, drowsiness and respiratory complications. This population also have a 25% incidence of cognitive impairment which may make communication and assessment of their pain more challenging.

Regional anaesthesia (RA) has been extensively researched in this group of patients with a view to improving the quality of pain relief while reducing the side effects of analgesic medications used. In 2017, a Cochrane review on RA in the management of patients with NOF fractures concluded that there was high quality evidence that RA reduces pain on movement within 30 minutes after block placement and reduces opioid consumption and moderate quality evidence that RA reduces the incidence of pneumonia, time to first mobilization and cost.