ABRA ASM Nottingham 2013: Key Points

Dr Steve Rowe (@Kangaroosteve) recently attended the Association of Burns & Reconstructive Anaesthetists ASM (November 2013) held in N0ttingham, and has very kindly provided us with his reflections on the talks.

The RCOA Matrix Codes for each talk are shown (in my opinion, the organisers didn’t provide them), along with the details of the speaker.

Association of Burns and Reconstructive Anaesthetists Nottingham 15th November 2013

Long Term Outcomes in Chronic Pain – do perioperative techniques alter outcome? (2E03): Dr Simon Tordoff, Leicester.

  • Chronic pain after surgery is common, but not often consented for
  • Hernia repair @ 1 Year – 19% some pain; 6% moderate or severe pain; 6% Severe pain restricting daily function (Callesen Br J Surg 1999)
  • These outcomes are verified by a very large Swedish study looking at their hernia registry (like our joint registry).
  • Knee replacements – 20% unsatisfied at 1 year due to pain (and pain commonest indication to perform surgery in first place….)
  •  Thoracotomy –   61% pain after 1 year, 3-5% severe pain; Neuropathic pain 21% at 7 years
  •  Amputation – 50-75% Phantom limb pain; 20-50% Stump pain
  • Given the above, the suggestion was that it may be prudent to screen for psychological vulnerability to develop chronic pain.

Significant risk factors are:

  1. Poor post operative pain control
  2. Pre-existing chronic pain
  3. Surgical complication
  4. Multiple surgeries
  5. Obesity and disordered glucose metabolism – sensitizes to post op pain.

Take home message – a conservative estimate of 2-4% severe chronic pain after surgery – probably should be consented for specifically, and a big national audit would be nice.

Opioid rotations and other strategies (2E01): Dr Doug Johnson, Birmingham.

S/E of opioids well known – constipation, N+V, Itch, tolerance

Opioid induced hyperalgesia (OIH) is recognised more, especially in burns patients.

OIH gives increased pain with increased doses of opioids, with a change in the pain charateristics – more diffuse, allodynia, aslong with neuro-excitation phenomena (this is something we are most familiar with – “post-remifentanil” patients in recovery).

Thought to be NMDA/Glutamate mediated.

Recognition is important. First line therapy is to increase the dose of opioid and evaluate for increased efficacy – this would be indicative of tolerance rather than OIH. If pain and other symptoms worsen, OIH likely.

Management

  1. Decrease or eliminate opioid
  2. Switch or rotate opioids
  3. Utilise other agents with NMDA receptor activity – ketamine/gapapentoid
  4. Utilise combination therapies – paracetamol/Nsaids etc etc

Opioid rotation

  • There is incomplete cross tolerance, with different drugs having a range of effects on other receptor systems e.g. Methadone and NMDA receptors
  • The switch is thought to allow the body to get rid of morphine-3-glucuronide, a metabolic product with no significant opioid receptor activity, but implicated in tolerance and other side effects.
  • Switching morphine to fentanyl often fails dues to rapid tolerance developing to fentanyl.
  • Methadone theoretically a good option.
  • Oxycodone also a viable alternative.

Ketamine

Cochrane review in 2010 supports is use in acute post op pain

http://summaries.cochrane.org/CD004603/perioperative-ketamine-for-acute-postoperative-pain

Ketamine in subanaesthetic dose (that is a dose which is below that required to produce anaesthesia) is effective in reducing morphine requirements in the first 24 hours after surgery. Ketamine also reduces postoperative nausea and vomiting. Adverse effects are mild or absent.”

Benefits shown with:

  1. Pre-incision bolus/Bolus at wound closure/continuous peri-operative infusion/post-op infusion with morphine.
  2. No benefit demonstrated with >30mg TOTAL in 24 hours
  3. Doses discussed for bolus treatment peri-operatively were in the range 75-100mcg/kg, though it seems that p to 0.5mg/kg can be used without a rise in side effects.

Gabapentin

  • Indirectly inhibits NMDA receptor overactivity
  • Only convincing evidence is that it decreases “Burns itch” – 300-1200mg tds po

Pregabalin

  • BD dosing, Lower doses, NICE approved
  • More expensive
  • >5% body surface area burns – gives a significant reduction in pain/itch and procedural pain
  • No difference in LOS or opioid consumption
  • No difference in pain at 6 months

Other talks were related to foreign forays providing anaesthesia for reconstructive surgery

The first was for reconstructive surgery after noma (cancrum oris) a disease of poverty in sub-Saharan Africa – the main thrust of the talk was that these patients have difficult airways, often with absolute trismus, but with very careful planning airway disasters were avoided. This involved a 2-consultant airway assessment and documentation of airway plan.

The second was a trainee presentation that won the Russell Davis and Stuart Laird Prize  – the trainee discussed providing regional anaesthesia in a resource poor environment.

The final discussion related to revalidation and appraisal. Whilst useful, it generated no significant take home points.

It is likely that the meeting next year will be held in Manchester, and Sheffield in 2015.

BSOA ASM London 2013: Key Points

I recently attended the British Society of Orthopaedic Anaesthetists Annual Scientific Meeting, November 2013.

In order to allow those who were unable to attend the meeting to gain a flavour of the topics covered by the speakers I have created a summary of the key points of each talk (in my opinion).

The RCOA Matrix Codes for each talk are shown (in my opinion, the organisers didn’t provide them), along with the details of the speaker.

An orthogeriatric perspective on the peri-operative care of patients with fractured neck of femur (2A07): Dr Celia Gregson, Bristol

  • Avoid drugs with anticholinergic effects due to risk of delirium in NOF. Remember constipation as a cause of confusion. Use Lactulose!
  • Orthogeriatrics view on NOF. Usual Hb drop 2.5g (4g in IM nail). Do Hemocue in PACU. Transfuse early so can mobilise next day.

Perioperative orthopaedics: The perfect translational research model (1A02): Dr Gareth Ackland, UCL

  • VISION study (JAMA 2012); 40K pats, age>45, non-cardiac SxGA. 12% had T-I inc (>50% asymptomatic w/o ECG changes). Assoc with inc LOS.
  • Research update: postop complications double mortality up to 10 yr postop! This includes “small” complications like wound infections.

What matters in cervical spine injury (2A01): Dr Rob McCahon, Nottingham

  • Direct laryngoscopy induces forces primarily at C0-C2 BUT lots of room here for the cord to flex & extend (only takes up 25% of available room). The space is decreased if your rotate the neck – avoid rotational forces at all costs.
  • Risk factors for c-spine injury: pelvic #, ISS > 15, age < 40. [Clayton Injury 2012]. Max-fax injuries not a factor (despite ATLS teaching).
  • < 50% of the normal population aged over fifty have evidence of canal stenosis/impingement on MRI. Don’t just take care in trauma cases!

Paediatric regional anaesthesia (2D05, 2G03): Prof Peter Marhofer, University of Vienna

  • aPPT frequently abnormal < 45 weeks post conceptual age. Not a CI to central neuraxial blockade.
  • ADARPEF study (2010) Complication rate for RA in children 0.12% (Central:Peripheral 6:1). No serious morbidity.
  • Paed RA: Supraclavicular best for upper limb as axillary nerves as superficial and difficult to visualise with USS

Lower limb arthroplasty, regional anaesthesia and outcome (2G01): Dr Barrie Fischer, Redditch

  • No clear benefit between analgesic technique & functional outcome or LOS. The total package of care is more important.
  • PROSPECT Guidelines: THR: SAB plus IT opiate or GA plus LPB. Little evidence for LIA. TKR: SAB plus IT opiate or GA plus FNB (not SNB)
  • THR/TKR: Meta-analyses show RA less blood loss, pain, PONV, and possibly VTE. In US >75% GA only 11% SAB. SAB decreases postop comps & RIP.
  • TKR: femoral nerve catheters are not associated with better analgesia compared to single-shot FNB and just impair mobilisation.
  • Enhanced Recovery & FNB. Adductor canal blockade may be no better in terms of ability to mobilise (RAPM 2013;38).
  • Local anaesthetic infiltration: not beneficial in THR; may be of value for 6-12 h in TKR (if used as part of multimodal analgesia regimen)
  • Do not ignore pain in favour of non-EBM local anaesthetic infiltration techniques. 36% of TKR pats end up with chronic pain, or which having severe early postoperative pain is a predictor.

Ultrasound for regional anaesthesia: Teaching, learning and competence (1H02): Dr John Barcroft, Royal National Orthopaedic Hospital

  • Training in USS & RA: 1. Go on good course 2. Learn sonoanatomy 3. Practice on phantoms & cadavers 4. Try on patients with an expert.
  • Dreyfus Skill Levels: 1. Novice 2. Competent 3. Proficient 4. Expert 5. Master. We should aim for expertise not competence in USS RA.
  • Newly acquired motor skills (e.g. USS RA skills) will almost degrade to baseline if not used for 18 days! No place for occasional USS RA!
  • Create your own USS phantom: 4 x packets of supermarket jelly with 25% of the recommended water, filled with some olives. Cost < £4!!
  • “Only those who have the patience to do simple things perfectly ever acquire the skills to do difficult things easily”. Practice USS!!

Pathophysiology and management of acute coagulopathy of trauma (ATC) (1A01, 2A05): Mr Ross Davenport, The Royal London

  • Acute trauma coagulopathy (ATC): 24% on arrival to ED. ATC directly related to ISS & base deficit and increases RIP by 400%.
  • ATC thought to be caused by “thrombin switch”. Thrombin production decreased and aPC activated (decreasing factors V & VIII).
  • ATC predominately aPC mediated thrombinolysis, not DIC (other clotting factors often still > 75%). Platelet dysfunction is also a factor.
  • Only 50% of those with ATC will have PT that is abnormal and the test will take > 60 mins. Use ROTEM/TEG for a diagnosis in < 5 mins.
  • ROTEM can miss occult fibrinolysis. Most of your trauma patients with ISS > 16 will be fibrinolytic and will need tranexamic acid.
  • Ratio of PRC:FFP:Plts still unknown. Probably not 1:1:1 but optimal ratios unclear. RCT in progress (PROPPR) – results awaited.

Damage control resuscitation and anaesthesia for major trauma (2A02): Major Claire Park, King’s College Hospital.

  • Trauma Team Dynamics. Good review J R Army Corps 2001; 157: S299-304. Concepts such as tunnel vision, situational awareness, task fixation.
  • Damage control anaesthesia: suggestion for RSI Fentanyl:Ketamine:Rocuronium 3:2:1 (reducing to 1:1:1 if unstable).