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Three Part Question

In [patients with dislocated hip prosthesis] does [general anaesthesia or conscious sedation] give a [better reduction rate]?

Clinical Scenario

An otherwise fit 71-year old lady presents to your department having slipped on the ballroom floor during a tea dance. She is unable to weight bear and has pain in her left hip. X-ray reveals a dislocation of her hip prosthesis, and she tells you that it's not the first time. You wonder if it's reasonable to sedate her and manipulate it in the department, or refer her to orthopedics to join the rather long emergency list, to be manipulated later. Perhaps days later. She is starved, and you have suitable anaesthetic experience.

Search Strategy

Medline 1950 - November week 1 2008, using the Ovid interface.
[hip dislocation.mp. or exp Hip Dislocation/] AND [exp Anesthesia, General/or general anaesthesia.mp. or exp Conscious Sedation/ or exp Anesthesia/]

Search Outcome

63 papers were found. No papers compared the use of general anaesthesia and conscious sedation for this procedure. Two papers presented the success rate using conscious sedation. A further two papers have been published.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Austin et al. 2003 USA	104 patients who had 114 orthopaedic procedures in the ED using iv methohexital (+/- opioids). These included 29 hip dislocation reductions.	Retrospective chart review.	Overall reduction rate	78.9%	The authors did not specify the success rate for hip dislocations.
			First time reduction rate	80.8%
			Complication rate	20.2% (mostly respiratory, all transient)
Frymann et al. 2005 UK	101 patients with unilateral dislocated prosthetic hip. Sedated with iv morphine and midazolam. Exclusions: ASA grade>2, dislocation>12 hours, neurovascular deficit, no consent, refusal, previous failure using sedation, only 1 doctor available, department too busy.	Prospective cohort.	Overall reduction rate	62% (95% CI: 53% - 71%)	Convenience sample
			Reduction rate for grade A dislocation (more than 50% contact between femoral head and acetabulum)	82% (95% CI: 52% - 95%)
			Reduction rate for grade B dislocation (less than 50% contact between femoral head and acetabulum)	54% (95% CI: 41% - 66%)
			Reduction rate for grade C dislocation (no contact between femoral head and acetabulum)	69% (95% CI: 53% - 82%)
			Complications	5 related to sedation, 1 from the reduction.
Mathieu et al, 2009, UK	98 Adult patients presenting with a dislocated hip prosthesis. All received iv morphine and then iv propofol as a 1 mg/kg bolus.	Prospective cohort	Reduction rate	94/98 (96%)	An observational study. Changes to the protocol during the study period.
			Adverse events	Eight had an episode of oxygen desaturation and four developed hypotension needing metaraminol. 42 Needed additional doses of propofol.
Gagg et al, 2009, UK	165 Adult patients with prosthetic hip dislocations attending one of five ED between 2005 and 2006.	Retrospective chart review	Reduction rate	67/104 (64%) with midazolam, 22/23 (96%) with propofol, 3/8 (38%) drug not recorded.	Changes to the protocol during the study period.
			Time to reduction	ED reduction, median time 2 h 21 minutes (n = 92). Failed ED reduction then theatre GA, median time 8 h 32 minutes (n = 43). Theatre GA, median time 8 h 10 minutes (n = 30).

Comment(s)

With the publication of two studies from the UK in 2009 there is now a body of evidence in favour of reduction of dislocated hip prostheses in the ED. This has the considerable advantage of achieving a speedier reduction than when a general anaesthetic is given in theatre. The studies quoted do not address what needs to be done after the successful reduction.

Editor Comment

ASA, American Society of Anesthesiology; ED, emergency department; GA, general anaesthesia.

Clinical Bottom Line

Patient safety is paramount. Operators must be adequately trained in both iv sedation and hip prosthesis manipulation. If these conditions are met then manipulation under sedation may be successful.

References

1. Austin T, Vilke GM, Nyheim E, Kelly D, Chan TC. Safety and effectiveness of methohexital for procedural sedation in the emergency department. Journal of Emergency Medicine 2003 24 (3): 315-318
2. Frymann SJ, Cumberbatch GLA, Stearman ASL. Reduction of dislocated hip prosthesis in the emergency department using conscious sedation: a prospective study. Emergency Medicine Journal 2005 22 (11): 807-809
3. Mathieu N, Jones L, Harris A, et al. Is propofol a safe and effective sedative for relocating hip prostheses? Emerg Med J 2009;26:37–8.
4. Gagg J, Jones L, Shingler G, et al. Door to relocation time for dislocated hip prosthesis: multicentre comparison of emergency department procedural sedation versus theatre-based general anaesthesia. Emerg Med J 2009;26:39–40.