1. H Aladin1, A Tameem2, M Rushton3, E Roe3, A Jennings4
Perioperative Pain Management of Limb Amputation – are perineural catheters the answer?
H Aladin1, A Tameem2, M Rushton3, E Roe3, A Jennings4
Department of Anaesthesia and Pain Management - The Dudley Group of Hospitals NHS Foundation Trust
1. Core anaesthetic trainee, 2. Consultant in Anaesthetics and Pain, 3. Specialist Pain nurse, 4. Consultant Anaesthetics
RESULTS
INTRODUCTION
limb amputation occurs with a frequency of between per 105 total population. It is well known to be associated with postoperative pain; in particular phantom limb pain (PLP). Poorly controlled acute postoperative pain can increase the risk of PLP. It is suggested that 50-85% of amputees go on to experience PLP. Optimization of perioperative pain has been shown to reduce the risk of PLP.
National Confidential Enquiry into Patient Outcome and Death for lower limb amputations (2014) suggested that patients seen perioperatively by acute pain specialists were found to have better overall pain management. Continuous peripheral nerve blockade via a perineural catheter has been shown to improve analgesia and reduce opioid-related side effects for patients undergoing lower limb amputation due to peripheral vascular disease.
Here we present our Trust lower limb amputation acute pain pathway which involved the use of local anaesthetic perineural catheters. We describe a service evaluation audit comparing the quality of pain relief provided before and after implementation of the new pathway.
PERIOPERATIVE ANALGESIA GUIDELINE
PREOPERATIVE REGIME:
Once decision for amputation, contact Acute Pain Team to optimize preoperative analgesia
Commence Gabapentinoids
Gabapentin (1st line)
If already prescribed, optimize dose – If previous treatment failed with Gabapentin, consider Pregabalin
Pregabalin (2nd line)
Initiate if fast onset is needed
Start at dose of 75mg bd, first dose in the immediate preoperative pain (2 hours prior to surgery)
Pre Guideline
Post Guideline
Sample Size 68 56
Age (mean) [range]
66 [20-91]
68 [29-94]
Male:Female
45:23:00
41:14
AKA (%)
26 (38)
33 (59)
TKA (%)
4 (6)
8 (14)
BKA (%)
38 (56)
15 (27)
Acute pain team preoperative review
19 (35)
Peripheral sciatic nerve catheter
 56 (100%)
INTRAOPERATIVE REGIME:
Anaesthesia (GA/RA) – as per the anaesthetist choice
Insertion of a perineural sciatic nerve catheter with an epidural catheter kit by surgeons +/- insertion of femoral nerve catheter with an epidural catheter kit or single shot femoral nerve block by the anaesthetist
Initial intraoperative bolus of 10ml of 0.25% bupivacaine through both the catheters irrespective of mode of anaesthesia
Continuous infusion – 0.2% Ropivacaine
Basal rate – 5ml/hr (10ml/hr if femoral + sciatic nerve catheters)
Bolus – 10ml of 0.2% Ropivacaine, 2 hour lockout
PCA morphine if appropriate
AIMS
A retrospective audit of lower limb amputations undertaken in our hospital highlighted poor postoperative pain control. Most patients had moderate or severe pain at some point during the 7 days post-operatively.
Following a literature review, a perioperative analgesia guideline was devised and implemented to address the pain management of lower limb amputations involving early acute pain team involvement and the placement of perineural local anaesthetic catheters (see below). The service was then re-audited prospectively.  
POSTOPERATIVE REGIME:
Gabapentinoids titrated to effect/side effects
Postoperative day 4 – Trial cessation of sciatic nerve catheter infusion. If pain recurs, restart 0.2% Ropivacaine infusion after a bolus of 10ml of 0.2% Ropivacaine via the pump
Postoperative day 6 - Repeat trial cessation
METHODS
A prospective six month audit of all patients who underwent either an emergency/elective lower limb amputation were included (‘post guideline”). Using a standard proforma, acute pain nurse specialists reviewed the patient records and charts, obtaining data regarding the perioperative pain scores. Data was interpreted and then a comparative analysis with the previous audit was undertaken prior to the implementation of the guideline (“pre guideline”).  
CONCLUSION
The audit has shown a considerable improvement in overall pain scores following the implementation of a perioperative management guideline for lower limb amputation.
There was reduced opiate usage which may improve morbidity outcomes.
Through the use of perineural catheters we have seen a substantial improvement in postoperative pain as compared to single shot nerve blocks and analgesia adjuncts alone. The guideline has been received positively by the department.
Currently there are no regional or national guideline for the management of pain with lower limb amputations and the work here is demonstrates potential towards a suitable protocol.
RESULTS
After introduction of the guideline, 43% of patients complained of a pain score >1 in the postoperative period as compared to 74% in the pre guideline cohort.
A greater proportion of patients were pain free in the post operative period (pain score = 0) compared to the pre guideline group. (74% vs 60%).
31 patients (55%) had been commenced on either gabapentin or pregabalin, an increase from 21% previously. 18 patients (26%) of patients received a PCA prior the guideline compared to 2 patients (4%) after the new guideline.
49/56 (88%) patients received no opiates immediate postoperative period. During the postoperative 6 day period, 12 patients required no additional breakthrough opioid analgesia.
100% of patients received a sciatic perineural catheter following the guideline introduction.
References
Gough MJ, Juniper M, Freeth H, Butt A and M Mason. National Confidential Enquiry into Patient Outcome and Death Lower Limb Amputation: Working Together. November 2014
Pinzur, M.S. et al., Continuous postoperative infusion of a regional anesthetic after an amputation of the lower extremity. A randomized clinical trial. The Journal of bone and joint surgery. American volume, 78(10), pp.1501–5.
Neil M, Grant C, Shepherd V, Colquhoun L. Development of a best practice guideline for the prevention and management of acute phantom limb pain. Pain News 2014;12(2):
Acknowledgements
Dr B Smith, Dr M Hodges, Dr K Eagland, Dr G Bainbridge