 CPSP is the MC and serious complication post surgery  No universally agreed definition  >4 million people undergo Sx in UK

 ↑ analgesic use  Restriction of activities of daily living  Sig effects on QOL  ↑ health care utilization

 What do you understand by the term CPSP ? (10 %)

CPSP is a type of neuropathic pain

 What types of Surgical procedures does it most commonly follows? (10%)

 Type of surgery Incidence of chronic pain (%) › Amputation 30–85 › Thoracotomy 5–67 › Mastectomy 11–57 › Inguinal hernia repair 0–63 › Sternotomy 28–56 › Cholecystectomy 3–56 › Knee arthroplasty 19–43 › Breast augmentation 13–38

 It may be related to the nerve injury, but not all patients with nerve injury get CPSP and not all patients with CPSP have nerve injuries

 Central sensitization Peripheral nerve injury ↑ Na+ channel expression ↑ Spont activity and discharge, ↑ Glutamate release from nerve endings Acts on Glutamate receptors, Intracellular changes Sustained Central sensitization

 What are the risk factors for the development of CPSP? (30%)

 Preop › Severe, long-term preop pain › ↓ with increase in age › Genetic susseptibility › Psychosocial factors e.g. fear of surgery

 Intra op › Longer, more complicated operation › Open (rather than laparoscopic) › Repeat surgery e.g. Hernia

 Post op › Adjuvant interventions e.g.Radiotherapy › Severe post-op pain

 What can be done to prevent it? (20%)

 Good post-op pain relief itself eg. Epidural/ Paravertebral  Gabapentin and IV Ketamine are being used  Targinact ®(newer agents) Oxycodone +Naloxone in fastrack colorectal surgery  No evidence for pre-emptive RA

 What is the management of CPSP ? (30%)

 Multimodal Multidisciplinary approach with rational use of polypharmacy  Pharmacological- WHO, Antidepressants, anticonvulsants, NMDA  Non-pharmacological  Psychotherapy (CBT, PMP)  Complementary therapies (Acu, TENS)  Functional rehabilitation  Others

 WHO analgesic ladder › Simple analgesics to Strong opiods › Anti depressants eg Amitryptilline › Anti convulsants eg. Carbamazapine › Calcium channel blockers eg. gabapentin › Directly acting eg clonidine › Nerve blocks › Acupuncture › Heat/cold, TENS