Recommandé
Contenu connexe
Tendances
Tendances (20)
En vedette
En vedette (13)
Similaire à Mellss pharm cns amide local anaesthatic
Similaire à Mellss pharm cns amide local anaesthatic (20)
Plus de nur amalina aminuddin baki
Plus de nur amalina aminuddin baki (20)
Dernier
Dernier (20)
Mellss pharm cns amide local anaesthatic
- 1. Amide Local Anaesthatic Nur Amalina bt. Aminuddin Baki 60
- 2. Introduction • Amide link: covalent chemical bond
- 3. Amide Local Anaesthetics Longer acting • Bupivacaine • Ropivacaine • Etidocaine • Dibucaine Intermediate acting • Lignocaine • Mepivacaine • Prilocaine
- 4. Bupivacaine
- 5. Ropivacaine • Intermediate onset • Compared to bupivacaine – Less potent – less cardiotoxic – Similar action duration – More motor sparing • For infiltration, epidural and regional anaesthesia • Continuous epidural use for post-operative and labour pain relief
- 6. Etidocaine • Fast onset, analgesia 2-3 times longer • For infiltration and nerve block anaesthesia • Peridural analgesia ( more motor blockade and abdominal muscle relaxation) • Limited use in vaginal delivery ( block expulsion) • X spinal anaesthesia – May produce convulsion • Similar cardiotoxic with bupivacaine
- 7. Dibucaine / Cinchocaine • Very potent, longest acting, slow onset, rarely used • For surface anaesthesia in anal canal and rectum and spinal anaesthesia of long duration • More toxic than bupivacaine • Pseudocholinesterase inhibitor
- 9. Lignocaine / Lidocaine / Xylocaine • Most widely used ,multipurpose, fast, • Max. effect : 2-5 minutes, lasts for 30-45 min • Useful for all types of blocks • Available as: 4% topical solution, 2% jelly, 5% ointment, 1%, 2% injection ,5% spinal anaesthesia and 10% spray • Formulation with epinephrine: – Delay absorption ,prolong action,reduce toxicity • Intratechal/ epidural of lidocaine with opioid analgesic (SYNERGISTIC)
- 10. • Cause – (low) drowsiness – (increased) dizziness, paraesthesia, euphoria – (high)confusion, vertigo, tinnitus, nausea • Precipitate seizure, respiratory depression, coma – Treatment: Diazepam/ Thiopental • Other uses: – IV : ventricular arrythmia during MI • Propanolol impair clearance, increasing toxicity
- 11. Mepivacaine • Compared to lidocaine : – More rapid onset – Longer action – Not effective as topical • Similar toxicity to lidocaine
- 12. Prilocaine • Intermediate onset and duration • Poor VSD • Cause CNS toxicity – Restricted to dental procedure (infiltration, nerve block ) • Used in eutectic mixture • Similar lidocaine toxicity except: – Orthotoluidine cause neonatal methaemoglobinaemia – IV methyl blue
- 14. Eutectic Mixture • Lignocaine + Prilocaine • Preparation for anaesthesia of intacted skin • Low melting point of mixture penetrate intact skin • Dermal anaesthesia during venesection, skin graft, IV cannulation • Apply an hour before procedure
- 15. Conclusion Ester • Poor penetrability • Short duration • Hydrolysed by plasma and liver esterases • Hypersensitivity common Amide • Good penetrability • Longer duration • Degraded by hepatic microsome • Rare hypersensitivity
- 16. Referance • HL Sharma and KK Sharma, Principles of Pharmacology,2nd edition, 2012. • Padmaja Udaykumar, Textbook of Medical Pharmacology, 2nd edition, 2010.