Fractured Neck of Femur (#NOF)

Summary

  • Dose:

    • DHS: 1.5 ml (7.5 mg) 0.5% hyperbaric or isobaric bupivacaine + 15 mcg fentanyl.

    • Hemiarthroplasty: 1.8 ml (9 mg) 0.5% hyperbaric or isobaric bupivacaine + 15 mcg fentanyl.

  • Position: Lateral (hyperbaric – operative down, isobaric – operative up). Can utilise set time 15 minutes for hyperbaric.

  • Expectation: Surgical block for up to 2 hours post-spinal.

Pre-Spinal Nerve Block

  • Facilitates patient turning. Can also help avoid pain on closure during longer procedures.

  • 150 mg ropivacaine is acceptable in patients ≥ 50 kg (as maximum dose 3 mg/kg).

  • Fascia iliaca block with 40 ml 0.375% ropivacaine, or a femoral nerve block (+/- lateral femoral cutaneous nerve block) with 20 ml 0.75% ropivacaine.

Evidence

  • Detailed analysis of 11,130 patients in UK has led to the development of a set of standards which outline the above recommendations [1,2]. These are available at www.hipfractureanaesthesia.com.

  • Data from the Brighton Hip Fracture Database (1909 patients) revealed a median duration of surgery (entry into theatre to end of surgery) of 83 minutes [3]. Surgery lasted longer than 120 minutes in 8.1%. Spinal anaesthesia ‘failed’ on 61 occasions (3.8%), but only twice during surgery (probably failures of sedation rather than sensation). Of the successful spinals, 50.1% involved doses of £ 1.5 ml 0.5% heavy bupivacaine.

  • Utilising a spinal catheter, the mean cumulative dose of 0.5% isobaric bupivacaine required for repair of proximal femur fracture has been found to be 1.14 ml (5.7 mg) [4].

  • 4 mg isobaric bupivacaine plus 20 mcg fentanyl (diluted to 2 ml with NaCl 0.9%) (patient lateral with operative side up, immediately supine) reached a median block height of T8 in one study [5]. It was completely satisfactory and nearly eliminated the need for vasopressor support. Spinal to end of surgery times were ~ 80 minutes.

References

  1. Secondary analysis of outcomes after 11,065 hip fracture operations from the prospective UK Anaesthesia Sprint Audit of Practice (ASAP-2). Anaesthesia 2016; 71: 506-514.

  2. Anaesthesia for 1131 patients undergoing proximal femoral fracture repair: a retrospective, observational study of effects on blood pressure, fluid administration and perioperative anaemia. Anaesthesia 2011; 66: 1017-1022.

  3. White. Duration of low-dose spinal anaesthesia for hip fracture surgery. Anaesthesia 2017;72:127

  4. Determination of the minimum initial intrathecal dose of isobaric 0.5% bupivacaine for the surgical repair of a proximal femoral fracture. Eur J Anaesthesiol 2015;32:759-763.

  5. Ben-David. Minidose bupivacaine-fentanyl spinal anaesthesia for surgical repair of hip fracture in the aged. Anesthesiology 2000;92:6-10.