Peripheral Nerve Blocks for Hip Fractures Save

JAMA reviews the use of peripheral nerve block with hip fractures as an effective pain management strategy that can be performed by credentialed clinicians outside of the operating room.

Hip fractures are common, especially in older adults (≥65 years), and may include a 1-year mortality rate of 12% to 25%. In the US, there were approximately 290 130 hospitalizations and 7731 deaths related to hip fractures in 2019. 

In addition to significant pain that may require narcotics or other risky interventions, nearly half of hospitalized hip fractures patients will have complications, such as delirium, pneumonia, acute kidney injury, urinary tract infection, and deep vein thrombosis.

Hip fracture pain management has largely hinged on systemic opioids and nonsteroidal anti-inflammatory drugs (NSAIDs), both of which have significant risks in the elderly. 

This paper addresses an opioid-sparing pain strategy that may be used in acute management, preoperative care, interfacility transfer, and inpatient care of patients with hip fractures.

Peripheral nerve blockade for hip fractures, typically performed by anesthesiologists and pain specialists, involves injection of a local anesthetic close to the sensory nerves supplying the anterior capsule of the hip joint, which is the main source of postoperative pain. Key nerves involved in sensory innervation of the anterior capsule include the femoral, obturator, and accessory obturator nerves. Peripheral nerve blocks use local anesthetics with a prolonged duration of action (6-8 hours), such as bupivacaine (maximum dose, 2 mg/kg) and ropivacaine (maximum dose, 3 mg/kg), and 4-mg dexamethasone applied perineurally, can be added to extend the block duration (for up to 5 hours).

Potential complications of peripheral nerve blocks include vessel puncture or intravascular injection, with systemic toxicity or CNS symptoms, such as tinnitus, perioral paresthesia, and seizures, as well as arrhythmias, hypotension, and cardiac arrest.

Ultrasound guidance has enabled other credentialed clinicians, such as emergency medicine physicians, to perform peripheral nerve blocks for pain control in patients with hip fractures. 

For hip fractures, the femoral nerve and fascia iliaca compartment blocks, performed via suprainguinal or infrainguinal approaches, have the most robust evidence supporting their clinical use. The pericapsular nerve group block may be useful to facilitate patient mobilization due to its motor-sparing effects. Quadratus lumborum and erector spinae plane blocks have recently been used for hip fractures, but evidence is limited to case reports and series.

Systematic reviews of randomized clinical trials (RCTs), reveealed very few complications (temporary neurologic deficit) with ultrasound-guided nerve blockade for hip fracture. 

A 2020 Cochrane systematic review of 49 RCTs included 1553 patients with hip fracture randomized to undergo peripheral nerve blocks (with or without ultrasound guidance) and 1508 randomized to undergo no nerve block or sham block. They found that peripheral nerve blocks reduced pain on movement within 30 minutes and that peripheral nerve blocks reduced acute confusional state and other complications.