Update in Pain managementUpdate in Pain managementHIMAA ConferenceHIMAA Conference

Dr Tony WeaverClinical Director of Surgical Services

Director of Pain Management Clinic

Barwon Health

Pain Services Pain Services

What we are--What we are-- Acute Pain Service – In patient - -run

in conjunction with main Anaesthetic Dept. Pain Management Clinic ( Outpatients)

– Chronic (Persistent) Non-Cancer pain– Cancer Pain ( with Oncologists &

Palliative Care Physicians) Referral by GP’s, Hospital Medical Staff,

Private Medical and Surgical Specialists

Pain Pain ---- DefinitionDefinition

Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in such terms. IASP

Persistent (Chronic) pain is now recognised as a disease entity.– Symptoms, Signs, Pathology, Psychology.

Pain is a Pain is a Bio-Psycho-SocialBio-Psycho-Social problemproblem

So, we must take a Multi- disciplinary Approach

– Medical, Psychology, Physiotherapy.Review of diagnosis – M/discTreatment plan formulatedThen, Feed-back session with the patient

Pain Patho-physiologyPain Patho-physiologyTypes of PainTypes of Pain

Descartes model ( anatomical model )Physiological painClinical Pain(Injury +individual emotional

& physiological response) Nociceptive PainNeuropathic painSympathetically maintained pain

Pain ConceptsPain Concepts

Nociceptive PainNociceptive Pain Nociceptive Pain - Acute Pain ( also persistent)

– Stimulation of peripheral nociceptors, somatic and visceral, relayed to dorsal horn , modulated, and passed to perception centres.

– Identifiable cause– Acute post injury, post surgery pain– Arthritic pain– Inflammatory pain– Mechanical pain

Pain conceptsPain conceptsNeuropathic pain - CharacteristicsNeuropathic pain - Characteristics

Neuropathic Pain- pain generated from within the nervous system – Spontaneous pain – Burning pain– Stabbing , shooting pain– Dysaesthesiae (ants crawling)– Multi-dermatomal

Allodynia, Hyperalgaesia, Hyperpathia.

Pain ConceptsPain Concepts Sympathetically maintained painSympathetically maintained pain

– Peripheral Sympathetic fibre growth– Dorsal root ganglion ingrowth with adrenergic

fibres– Manifested by Vasomotor, Sudomotor, Trophic

Motor & extra-pyramidal changes– Usually accompanied by Neuropathic pain

features

CRPS / RSDCRPS / RSD

CRPS was called – Reflex Sympathetic Dystrophy– Causalgia ( kausis=burn, algos=pain)– Algodystrophy– Sudek’s atrophy– Peripheral acute trophoneurosis– Traumatic angiospasm– Post infarction sclerodactyly

Pain SyndromesPain Syndromes CRPS Type 1

and Type 2 ( post nerve injury)( Old terminology RSD and Causalgia)

Clinical presentation: – Neuropathic pain i.e. burning ,shooting,

multi dermatomal– Allodynia, Hyperalgaesia, Hyperpathia– Sudomotor, vasomotor, trophic tissue change,

osteopaenia– Motor & extra-pyramidal changes

Target Treatment strategiesTarget Treatment strategies

Medical– Pharmacological– Interventional

Psychology– Cognitive Behavioural Therapies

Individual & GroupsPhysiotherapy

– Always active exercises, restoration of function

Cognitive Behavioural TherapyCognitive Behavioural TherapyPsychology, Physiotherapy, MedicalPsychology, Physiotherapy, Medical

Individual and GroupsIMPACT and MG group work

– Certainly Interventional – Re- engineering of Beliefs– Re-establishment of Self -Efficacy– Restoration of Function

both Physically and Socially– Sustainable gains– 3 weeks full time + follow-up

Chronic , Persistent Pain.Chronic , Persistent Pain. Cancer PainCancer Pain

Cancer Pain– ~ 95 % managed with chemo/ radio therapy and

‘conventional’ analgaesics including Opioids, nsaid’s, Steroids, Adjuvant agents, Tramadol , Lignocaine, Ketamine.

Advanced management – includes specific nerve blocks e.g. splanchnic,

(coeliac) paraverterbral.– Intraspinal: Epidural and Intrathecal drug Rx

Interventional Therapies Interventional Therapies

Specific nerve and plexus targetsSpecific nerve and plexus targets

Peripheral & Cranial nerve blocksRadiofrequency lesioning

– Continuous and Pulsed current– Somatic afferents from facet joints

( Medial Branch of Post.Primary Rami.)– Dorsal root ganglia, sympathetic ganglia.

Cryotherapy

Interventional TherapiesInterventional Therapies Chronic non-cancer PainChronic non-cancer Pain

Epidurals: cervical, thoracic, lumbar, caudal Nerve root sleeve injectionsSacro-iliac joints

L.A. & Steroids

Epidurolysis : lysis of fibrotic tissue in epidural space

Interventional Therapies Interventional Therapies Specific nerve and plexus targets Specific nerve and plexus targets

Sympathetic Nerve blocksSympathetic Nerve blocks– Stellate– Thoracic– Lumbar L.A– Coeliac Neurolytic– Splanchnic R.F.– Hypogastric – Ganglion impar

Chronic - non-Cancer PainChronic - non-Cancer Pain

Intraspinal TherapiesIntraspinal TherapiesDiscovery of receptors in Spinal cord for

– Opioids– Adrenergic alpha agonists– Alpha 2 agonists ( Clonidine)– Serotonergic– GABA

Chronic - non-Cancer PainChronic - non-Cancer Pain

Intraspinal TherapiesIntraspinal TherapiesPortals

– Epidural and Intrathecal catheters.Implanted Pumps & Intrathecal

catheterAllows 10- 100 times decrease in dose c.f.

systemic delivery with increased efficacy and marked decrease in side effects.

Spinal column Stimulation/ Spinal column Stimulation/ Intrathecal pumpsIntrathecal pumps

SCS potentially good in CAREFULLY SELECTED patients for Neuropathic pain problems.

( Failed Back , CRPS Type 1 & 2,) Intrathecal pumps potentially useful for

- nociceptive pain states

lower body spasticity

cancer pain with reasonable prognosis

Chronic - non-Cancer PainChronic - non-Cancer Pain

Intraspinal therapiesIntraspinal therapiesSpinal Cord Stimulation

– Relies on the “Gate theory” principle – continuous non-noxious stimuli via A beta fibres inhibit nociceptive traffic in dorsal horn & cord.