1. Perioperative use of
gabapentin for orthopaedic
surgery

2. Research
 Knowledge Network (formerly e-library Scotland) title searches
 “gabapentin orthopaedic surgery”
 “gabapentin orthopedic surgery”
and
 “gabapentin surgery”
 Also, OVID search (24 articles with “gabapentin” and “surgery” in
title)
 Articles not in English rejected (rightly or wrongly)
 No useful additional articles found when using “orthopedic” for
“orthopaedic” except for an Editorial note retracting multimodal
analgesia articles written by Reuben (admitted to making most of his
work up)

3. Questions
 1. What is the evidence for
Gabapentin reducing acute pain
following orthopaedic surgery?
 2. What is the evidence for
Gabapentin reducing chronic pain
following orthopaedic surgery?
 3. What doses of Gabapentin are
recommended for peri-operative use?

4. Acute Pain
 Gabapentin: a multimodal perioperative drug? (Review
article, BJA 2007)
 Meta-analysis in “Pain” (2006) reported: Three sub-groups –
Single dose 1200mg preop
Single dose <1200mg preop
Multiple doses in periop period
 Pain intensity significantly decreased at 6 and 24 hours in
groups 1 and 2 (but not group 3).
 24-hour opioid consumption significantly reduced in all 3
groups.
 Overall, 27 studies on periop gabapentin identified in this
article
 7 ‘orthopaedic’ including spinal fusion/laminectomy, ‘major
ortho surgery’ and arthroscopic procedures

5. Acute pain
 (i). Preoperative gabapentin
decreases anxiety and improves early
functional recovery from knee surgery
(Anesthesia Analgesia 2005)
 One dose 1200mg oral gabapentin preop
vs. control. 20/20 subjects
 Gabapentin ‘reduced anxiety’ (visual
analogue scoring), reduced VAS pain
scores during intial hour of recovery (but
not subsequently) and allowed patients
to tolerate more passive/active knee
flexion.

6. Acute pain
 (ii). Effect of preemptive gabapentin
on postoperative pain relief and
morphine consumption following
lumbar laminectomy and discectomy
(Journal Neurosurgical
Anesthesiology 2005)
 Gabapentin 800mg (2 divided doses) or
placebo preop. 30/30
 No statistically significant findings

7. Acute pain
 (iii). Effect of gabapentin on post-op
pain [following major orthopaedic
surgery] (The Pain Clinic 2005)
 Unable to source reference but summary
–
 800mg or 1200mg preop. 30/15
 No statistical difference in pain score
reduction but opioid sparing

8. Acute pain
 (iv). Analgesic effects of gabapentin
after spinal surgery (Anesthesiology
2004)
 1200mg 1 hour preop. vs. placebo. 25/25
 Significantly lower pain scores (only up
to postop 4 hours – NS at 24 hours)
 Less vomiting and urinary retention in
treatment group (p<0.05)

9. Acute pain
 (v). A single preoperative dose of
gabapentin (800mg) does not
augment postop analgesia in
patients given interscalene brachial
plexus block for arthroscopic
surgery (Anesthesia Analgesia
2006)
 800mg 2 hours preop. 27/26
 No augmentation of postop analgesia

10. Acute pain
 (vi). Effect of oral gabapentin on
postoperative epidural analgesia
(BJA 2006)
 1200mg 1-hour preop and then
1200mg on 1st and 2nd postop days
(doses not divided). 20/20
 Lower pain scores and better ‘patient
satisfaction’. More dizziness

11. Acute pain
 (vii). Premedication with gabapentin:
the effect on tourniquet pain and
quality of intravenous regional
anaesthesia (Anesthesia Analgesia
2007)
 1200mg 1 hour preop. 20/20
 Decreased tourniquet-related pain and
reduced pain scores in early postop
period.

12. Acute pain
 Additional articles not identified by BJA
review:
 (viii). Pre-emptive gabapentin significantly
reduces postop pain and morphine
demand following lower extremity
orthopaedic surgery (Singapore Medical
Journal 2007)
 300mg 2 hours preop. 35/35
 Significant decrease in postop pain and
rescue analgesic requirements
 Lower VAS scores at 2, 4, 12 and 24 hours

13. Acute pain
 (ix). Adding Gabapentin to a multimodal
regimen does not reduce acute pain, opioid
consumption or chronic pain after total hip
arthroplasty (Acta Anaesthesiology
Scandinavia 2009)
 3 groups: (P/P-39, G600/P-40, P/G600-38) Gaba
1-2 hours pre-op or Gaba in PACU
 Regional anaesthesia used
 Similar opioid consumption overall and no
difference in pain scores at 12,24,36,48h
 No difference found in sedation, N&V or dizziness
either (unlike most other studies)
 [No significant (p ‘>’ 0.05) difference in chronic

14. Which papers are joint
replacement studies?
 (1st study: Preop gabapentin decreases anxiety and improves
early functional recovery from knee surgery = Ant. cruciate
ligament surgery)
 Effect of oral gabapentin on postop epidural analgesia (BJA
2006)
 ‘Lower extremity surgical procedures’ ?which ops
 Pre-emptive gabapentin significantly reduces postop pain and
morphine demand following lower extremity orthopaedic
surgery (Singapore Medical Journal 2007)
 ‘Lower extremity orthopaedic surgery’ ?which ops
 Adding Gabapentin to a multimodal regimen does not reduce
acute pain, opioid consumption or chronic pain after hip
arthroplasty (Acta Anaesthesiology Scandinavia 2009)

15. Chronic pain
 From 2002 to 2006, 4 RCTs using perioperative gabapentin to
prevent chronic pain after amputation, breast and abdominal
surgery.
 Post-amputation paper:
 A randomized study of the effects of gabapentin on
postamputation pain (Anesthesiology 2006)
 Gabapentin started immediately after surgery (??) and
continued for 30 days. Treatment started on postop day 1
from 300mg to 2400mg days 13 – 30 (adjustment if renal
impairment).
 33/46 completed study.
 No reduction in incidence or intensity of post-amputation
stump and phantom pain.

16. Chronic pain
 Conclusions from other papers (under-
powered, high dropout rates):
 Incidence of burning pain significantly
reduced but no effect on incidence of overall
chronic pain, its intensity or the need for
analgesics 3 months after surgery
(mastectomies/lumpectomies with axillary
dissection)
 Borderline significant reduction in number of
patients requiring analgesics at 3 months
(same ops as above)
 Incisional pain following hysterectomy similar
in study and control groups at 3 month follow-
up

17. So, the ‘answers’
1. What is the evidence for Gabapentin reducing acute pain following
orthopaedic surgery?
 Body of evidence that acute pain can be reduced perioperatively using
gabapentin
 However, better evidence that only ‘early’ postop pain is significantly reduced
 Few orthopaedic joint studies
 Cochrane review on ‘established acute postop pain’ found little evidence for
the use of single dose gabapentin
 Summary
 Evidence mainly supports opioid sparing effects of gabapentin when used
perioperatively (for multiple surgical procedures). But, significantly higher
incidence of sedation.
 Gabapentin may have benefit for acute pain particularly in the early post-op
period.
 If it’s going to be used, should probably be given pre-emptively.

18. The answers
2. What is the evidence for Gabapentin reducing chronic pain following
orthopaedic surgery?
 Seems like a good idea but…
 There doesn’t appear to be any good evidence.
 Studies looking at other surgical procedures have been poorly performed.
 Summary
 Jury out.
 The role of perioperative pain management preventing chronic pain is
unproven.
 As an aside:
 Some patients may develop withdrawal from gabapentin (similar to alcohol
withdrawal syndrome)

19. The answers
3. What doses of Gabapentin are recommended for peri-
operative use?
 Dose-response relationship has not been adequately
addressed
 However, optimal preemptive dose for lumbar discectomy
thought to be 600mg (J Neuro Anesth 2005)
 BJA recommended 900mg
 Few studies used multiple dosing regimes (most simply one
dose pre-op)
 Only one orthopaedic study which looked at multiple doses
(Effect of oral gabapentin on postop epidural analgesia, BJA
2006)
 BJA review article recommends that ‘gabapentin given as
multiple doses perioperatively offers no additional benefit in
terms of pain reduction and opioid sparing when compared
with a single preoperative dose’