Acute and chronic pain Dr. Štoudek, Dr. Křikava Prof. Henrik Kehlet Prof. Narinder Rawal Acute Pain Service Definition - Merskey 1967, WHO, IASP •An unpleasant sensory or emotional experience associated with actual or potential tissue damage or described in terms of such damage • • • •„Pain is, what patient feels, when he says, that he feels pain “ •Margo Mc. Caffery Difficult to apply definition •Small children •Verbal handicapped adults •Mentally disabled •Patients with dementia •Patients suffering from alexithymia Pain •= subjective experience • •Could be affected: •Age •Gender •Cultural habits •Previous experience Congenital loss of feeling of pain Patophysiology of pain •Nociceptors, polymodal nocisensors •C fibre nociceptors •A fibre nociceptors •Posterior horns of spinal cord •Tractus spinothalamicus, spino-bulbo thalamicus, spinoreticularis •Brain pain centers (gyrus precentralis….) •Supressive mechanisms (GABA, opioids..) Classification of pain 1.Acute pain x chronic pain 2.Nociceptive pain x neuropathic pain 3.Psychogenic pain 4. Malignant pain x non-malignant pain •Pain caused by cancer (infiltration of bone, viscera…) •Pain as sequelae of cancer treatment (post-surgical, post chemotherapy, post radiotherapy…) Classification of pain Acute pain •Useful pain, physiologic pain •AP is symptom of disease •Fulfill basic role of pain – protect organism against injury, disease … •Short duration – hours, days.. Max. 3 months •Duration of acute pain is adequate to causality of this pain •Sharp, itching, localized pain, •Localization is the same as causality •Stimulation of sympathetic syst. •Main risk of AP is its chronification Chronic pain •CHP is syndrome, disease •Long duration – more than 3 months •Usually connected with depression •Parasympathetic stimulation •Constipation •Social isolation Somatic pain •Cause: stimulation of nociceptors • •Types: 1.Somatic (muscles, skin, joints) 2.Visceral (internal organs) • •Character:somatic pain is good localized, sharp •Visceral: dull and difficult for localization, sometimes reffered pain Neuropathic pain •cause: dysfunction of nerve systems (peripheral, central, vegetative) •types: 1.peripheral (peripheral nerves, nerve roots),Trigeminal neuralgia, post herpetic neuralgia 2.central (brain, spine) central post stroke pain 3. •Character: stable pain, paroxysmal pain with intensive pain atacks, alodynia) trigeminal neuralgia, postherpetic neuralgia Other types of pain •Mixed pain: •Pain contained nociceptive and neuropathic type of pain (FBSS) • •Psychogenic pain Pain measurement Possibilities of pain treatment •Pharmacotherapy •Physical treatment and rehabilitation •Psychotherapy •Invasive pain treatment methods •„Alternative“ treatment approaches (homeopathy, acupuncture ….) Acute vs. Chronic Pain Management •Acute Pain •Most often treated with: •NSAIDS •Opioids •Local anesthetics •Splinting •Positioning changes •Ice •Chronic Pain •Most often treated with: •Anti-seizure medications •Anti-depressant medications •NSAIDS •Implantable devices •Psychological therapy •Acupuncture • •When everything else fails and benefits outweigh risks •Opioids Acute Pain Service •Provides 7 days per week, 24 hour consultative services every day of the year. •Staffed by anaesthesiologists, nurse practitioners •Manages IV PCA (patient controlled analgesia), epidural catheters, nerve block catheters. Center for Pain Management •The Pain Center is located in the Ambulatory Care Pavilion •Treatments offered •Comprehensive evaluations •Epidural steroid injections •Spinal injections •Nerve blocks •Psychological evaluation and treatment •Opioid risk evaluation • • WHO ladder of pain treatment http://www.patientresource.com/userfiles/image/Pain%20Relief%20Ladder%20(no%20copyright).jpg WHO 3 steps analgesics ladder •For mild pain, use non-opioid first •When pain persist or increases, add an opioid •If pain becomes more severe, increase the opioid potency or dose •Schedule doses on around-the-clock basis, with additional PRN doses-rescues Adjuvant analgesics •Anticonvulsants •Antidepressants •Corticosteroids •Neuroleptics •Anxiolytics •Muscle relaxants •Anesthetics •antispasmodics Analgetic of the I step •Analgetic – antipyretic: 1.Paracetamol (acetaminophen) 2.NSA (non steroid antiphlogistic): onon selective COX inhibitors (ibuprofen, diclofenac, naproxen, indometacin) oCOX II preference inhibitors (nimesulid, meloxicam) oCOX II selective inhibitors (celecoxib, parecoxib (Dynastat), valdecoxib) o(Arcoxia) Analgetic of the II step •Weak opioids: •Codeine ( max. 240 mg/d) •Tramadol (max. 400 - 600 mg/d; µ agonist, norepinephrine and serotonin reuptake inhibitor) •Hydrocodone (DHC) max 240mg/d •Oxycodone in combination with nonopioid •Tapentadol (µ agonist, norepinephrine reuptake inhibitor) Analgetic of the III step •Morphin SR •Fentanyl •Oxycodone •Morphin IR •Buprenorphine •Hydromorfone •Methadone The most frequent mistakes in chronic pain treatment Invasive Pain treatment - indications •In case of lack of effect of pharmacotherapy •Pharmacotherapy with severe adverse event •Supplement of Pharmacotherapy Types of blockades •Reversible x irreversible •Vegetative x somatic •single x repeated x continual •Diagnostic x prognostic x therapeutic Division of blockades due to localisation §Local application of LA (reflexive blockades, trigger points, tender points, painful scars, intraarticular applications (SI? …) §Peripheral nerve blockades (axillar, and intercostal nerve block) §Paravertebral blocks §Central (spinal) block (epidural, subarachnoid) Epidural application of steroids • Indication •Acute (days) and subacute (weeks up to 3-6 months) radicular pain (pain irradiating do leg) and caused by intervertebral disc herniation. •CT exam. •Patient is not indicated to back surgery Recommendation after a application •2 weeks of resting regime •First improvement of pain during 2-3 weeks •4 weeks next visit in pain amb. •From 6 th moth after appl. Started rehabilitation •Recommended daily exercising (15-20 min) - improve body muscle unbalance Subarachnoidal analgesia •Single shot – before surgery – 24 hours post surgery analgesia •LA + morphin spinal 0,2-0,3 mg •Subarachnoidal catheters •Spinocath •Subarachnoidal ports Subarachnoidal ports •Treatment of chronic pain – moths, years (FBSS, Cancer) •Patient or his family training of applications •To Be prepare to solve complications of this treatment method (CNS infections, local infections, technical complications, withdrawal syndrome) Neuromodulation • Neuromodulations centres in CZ •FN Homolka •FN Motol •ÚVN Praha •FN Olomouc •FN Brno •FN u sv. Anny v Brně Necessary pre-implantation examinations •Neurologic •Psychologic!!!! •Psychiatric •Immunology •Orthopaedic or neurosurgery •Summary of health condition from GP •Algeziology exam •Positive result of test period Indication •SCS – spinal cord stimulation ØPredominant neuropathic lower limb pain • •Subarachnoid pumps ØPredominant low back pain • Subarachnoidal programmable pump – test period •Insertion of subarachnoid catheter •Connecting of external programmable pump •Setting of adequate mode for application •1 week in patient, 1 week out patient (better simulation of normal daily life of pat.) Sympathetic blocks • Sympathetic blocks •Reversible ØLokální anaesthetic • •Ireversible ØEtanol 50–80% ØFenol 6-8% • Ganglion stellatum – cervical sympathetic syst. •Upper cervical ganglion (C2-C3) •Middle cervical ganglion (C4-C6) •Lower cervical ganglion, ggl. Stellatum (C7 -Th1) • Indication •CRPS I. a II. Type (after surgery or injury, prolonged healing and oedema, followed with muscle atrophy and articulation freezing •Post herpetic neuralgia •Phantom pain •Morbus Paget •Post radiation neuritis •Raynaud's disease Therapy •Series of 10 blocks, Marcaine 0,25% 10 - 15ml •Possibility of blockades of other nerves in this region (n. glossopharyngeus, n. recurrent – gulping disorder, huskiness) •Presence of Horner´s trias • Neurolysis of ggl. coeliacum •Epigastrial pain •(painful attacks in case of chronic pancreatitis, cancer of pancreas – very painful type of cancer • •Blockade under CT control Thank you for your attention