Sunday, September 22, 2013

Blocked - ED Analgesia for Hip/Femur Fractures

The Gist: Emergency physicians can safely provide regional analgesia under ultrasound guidance in patients with hip and femur fractures. Implementation of this analgesic modality has been slow in the US, probably secondary to knowledge translation issues, but momentum in practice and the literature base is growing. Check out this great Free Open Access Medical education (FOAM) podcast on femoral nerve blocks and nerve blocks in general. As a medical student and resident, I received training and performed these blocks with anesthesia in the peri-operative setting, an experience I highly recommend.

The Case: An 81 year old female presented to Janus General's ED status-post fall with a shortened, externally rotated left leg. The patient complained of severe pain, pulse 105, BP 110/70.  X-rays showed a left intertrochanteric hip fracture, orthopedics consulted, and the patient received <0.1 mg/kg morphine.  The patient continued to report pain and was noted to be in atrial fibrillation, with a ventricular response of 130, and BP 96/60 on the monitor.  She was rate controlled with diltiazem, spontaneously converted her rhythm, remained uncomfortable throughout her ED stay, and received her surgery later in her hospital course.  A discussion over the potential for an ED placed nerve block initially failed (see section: "Why aren't we doing this more?') but after the patient's less than easy ED course, interest in this modality grew - could/should we do this in the ED?

Why a nerve block?
  • Better pain control compared with standard care (opiates, typically) in both femur and hip fractures, with a hearty duration of analgesia [1-5].
    • In addition to many studies without a placebo group, a small ED RCT comparing placebo (saline) to ultrasound guided femoral nerve block in hip fracture patients, who also received standard care (morphine) demonstrated superior pain control [2]. 
  • Reduced consumption of opioids/additional analgesics [1-5].  
    • Note: While we can imagine ways in which this could result in clinically important benefits such as preserved mental status and respiratory and cardiovascular stability, this surrogate measure doesn't necessarily translate into a patient oriented outcome. 
  • Trends toward less delirium [1].  Both severe pain and pharmaceuticals can caused patients to be altered.  Limitations: most studies excluded patients with dementia or other cognitive impairments and this mostly stems from the in-patient literature.
  • It's safe, especially under ultrasound guidance [1-5,7-9].
  • It's easy and physicians typically feel comfortable after brief training sessions  [7, 11].
Type of regional anesthesia - Two main types exist for these indication, the femoral nerve block (FNB) and the fascia iliaca compartment block (FICB), sometimes called a "modified FNB," as it deposits anesthetic in a similar region [8].  Detailed instructions: Ultrasound podcastNeuroaxiom website. Note: a good neurovascular exam should always precede a nerve block.
  • FICB (video) - targets the nerves of the lumbar plexus (L2-L4) and provides more proximal coverage than the femoral nerve block with a larger volume (typically bupivacaine diluted with saline).  Operator places needle more laterally than in the FNB, thereby reducing risk of intravascular infiltration/damage (use of ultrasound for both techniques weakens this point).  Landmark technique can be performed safely without ultrasound, if needed [5,7]. Probably covers the hip better than the FNB.
  • FNB - sometimes called a "3-in-1 block", as the goal is to target the femoral, lateral femoral cutaneous, and obturator nerves.  Routinely used for femur fractures in the pediatric population. 
  • Definitive literature on which block performs best is lacking, especially since most relied upon landmark techniques or nerve stimulators rather than ultrasound guidance.  Some anesthesiologists scoff at the notion of FNB for hip fracture and find the FICB more reasonable; however, there's literature to support FNB in acute hip fracture management as well [2,3].  
    • Likourezos et al from Maimonides Medical Center just finished a study of hip fracture patients randomized to FICB, FNB, or intravenous morphine. Results are pending but may help elucidate this distinction. 
Are people actually doing this?
  • Yes.  Much medical practice is location dependent, owing to the interests, training, and flux of individuals/thought and this is no different.  Dr. Al Sacchetti described the integration into his practice in the EMRAP Feb 2012 episode, and EPMonthly featured an article as well.  Here are some thoughts from the UK and commentary from Australia:  

  • It's not just a bunch of procedure hungry members of the FOAM community pushing a sexy procedures, core texts such as Tintinalli recommend considering FNB in hip fracture [6].  Papers report that since 2004 in some Denmark hospitals, ED placed FICB are routinely administered in hip fracture patients prior to x-ray in Denmark [7].
Why aren't we doing this more
  • Lack of knowledge.  While many people have been doing this for years and uptake appears to be greater outside of the US, some are unaware that this modality is easily and commonly performed by emergency physicians.  
    • A survey of emergency physicians in 3 Canadian teaching hospitals demonstrates that while the majority acknowledged the benefit of the nerve blocks in hip fractures, the majority did not perform them [10].  This argues against the assertion that lack of knowledge is key and is more likely a knowledge translation issue.
  • Time.  It's initially quicker to order morphine on the computer than 10-15 minutes at the patient's bedside but we may fail to consider the potential consequences of analgesics/sedation in vulnerable populations.  However, re-dosing of opioids is common, especially as patient's may be in the ED for several hours and complications of these interventions may also end up resulting in more time demand on the EP.  
    • Note: Time estimate based on my experience as a trainee in the OR setting (which included consent and components not typically performed in ED FNB/FICB blocks: full sterile drape/procedure, and catheter placement). Studies have demonstrated feasibility in the ED setting [2-5,7].
  • Consultants.  Confrontation with orthopedics is a commonly cited excuse for not providing regional anesthesia in the ED, yet often this is cited without talking with ortho about a particular patient's case.  Instead of initiating dialogue, it's often assumed that the orthopedist will decline.


  • Although, safely performed around the world for decades, it's relatively new in US EDs and therefore hasn't become routine like many other places.  Intravenous analgesia has been a mainstay of many ED pain complaints for years and has become routinized and we may skip over thinking - "What is best for this patient?" An increasing number of emergency departments have protocols to place blocks prior to x-rays in patients over 50 with hip/femur fractures.  The US emergency department literature on this analgesic modality is growing quickly, but much of it stems from the 21st century and many EPs have not received formal training [10].  There's a balance between being an early adopter and waiting to be pushed to adopt a practice.  
  • Ultrasound is an integral part of EM residency training in the US and is creeping into medical school curriculum.  Utilization of ultrasound may be daunting for some who have become accustomed to a particular practice pattern. 
Downsides:
  • Duration of analgesia - this is part of the benefit of the nerve block.
  • Interference with motor movement - Some argue that a patient may be more prone to falls but this is in the in-patient/operative literature and has not resulted in any increase in mortality or morbidity [1].  This has not been demonstrated in any of the ED literature, and is amenable to fall protocol/precaution [2-5, 7].
  • Concerns about ay also mask a developing compartment syndrome.  Case reports exist of compartment syndrome in the setting of a nerve block, but these are post-operative and the breadth of the literature doesn't support this as a concern in most patients [8].
  • Like any procedure, there are risks such as infection, bleeding, nerve damage, etc; however, these are exceedingly rare and a risk-benefit evaluation is necessary [1-5, 7-9].
References:
1. Abou-Setta AM, Beaupre LA, Jones CA, et al. Pain Management Interventions for Hip Fracture. Comparative Effectiveness Review No. 30. AHRQ Publication No. 11-EHC022-EF. May 2011.
2. Beaudoin FL, Haran JP, Liebmann O. A comparison of ultrasound-guided three-in-one femoral nerve block versus parenteral opioids alone for analgesia in emergency department patients with hip fractures: a randomized controlled trial. Acad Emerg Med. 2013;20(6):584–91.
3. Beaudoin FL, Nagdev A, Merchant RC, et al. Ultrasound-guided femoral nerve blocks in elderly patients with hip fractures. Am J Emerg Med. 2010;28(1):76–81. 
4. Haines L, Dickman E, Ayvazyan S, et al. Ultrasound-guided fascia iliaca compartment block for hip fractures in the emergency department. J Emerg Med. 2012;43(4):692–7. 
5. Godoy Monzon D, Iserson K V, Vazquez J a. Single fascia iliaca compartment block for post-hip fracture pain relief. J Emerg Med.  2007;32(3):257–62. 
6. Steele MT.  Tintinalli's Emergency Medicine.  7th ed.  p 1856.
7. 1. H√łgh A, Dremstrup L, Jensen SS, et al. Fascia iliaca compartment block performed by junior registrars as a supplement to pre-operative analgesia for patients with hip fracture. Strategies in trauma and limb reconstruction (Online). 2008;3(2):65–70.
8. Karagiannis G, Hardern R. Best evidence topic report. No evidence found that a femoral nerve block in cases of femoral shaft fractures can delay the diagnosis of compartment syndrome of the thighEmerg Med J. 2005 Nov;22(11):814.
9. Wedel DJ, Horlocker TT. Miller's Anesthesia. 7th ed. pp. 1652-1655.
10.Haslam L, Lansdown A, Lee J, et al. Survey of Current Practices: Peripheral Nerve Block Utilization by ED Physicians for Treatment of Pain in the Hip Fracture Patient Population. Canadian geriatrics journal : CGJ. 2013;16(1):16–21.

3 comments:

  1. Excited to be referenced on your post. Thanks for the great summary.

    Jeff
    @DrTLDelt

    ReplyDelete
  2. Femoral nerve blocks, or more accurately fascia iliaca compartment blocks are part of our routine care of fractured neck of femurs.

    My old ED had an integrated NOF pathway with patients over 50 admitted under the medical aged care team with orthopods providing the fixation. As part of their routine care ED would place a block before the patient even goes to imaging. The thing I like most about these blocks is that they can drastically reduce opiate analgesia requirements in a population that are highly susceptible to their adverse effects.

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  3. I stumbled upon this post while researching for anesthesia-related topics and the case/example really helped. Just want to say thanks for this excellent article.

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