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1. LOCAL ANAESTHESIA Dept Of Oral And Maxillofacial Surgery VSPM’S Dental College, Nagpur )

2. CONTENT Introduction History Definition Desirable properties Mode of impulse transmission Mechanism of action of L.A Factors affecting L.A action Classification Pharmacology

3. Composition of L.A Systemic effects of L>A Topical Local anesthetics Containdications of L.A Vasocontrictors Clinical aspects Complications Future Directions Summary CONTENT

4. INTRODUCTION The efforts of human kind to find the means to control pain presents as one of the greatest challenges in medicine. Pain is the phenomenon wisely instituted by nature as a warning sign of a condition that may be detrimental to our bodies. Pain-free operating is of obvious benefit to the patient, it also helps the operator as treatment can be performed in a calm, unhurried manner. Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

5. Local anaesthesia is the mainstay of pain control for outpatient oral surgical procedures. The ability to provide safe, effective local anaesthesia is the cornerstone of clinical oral surgical practice. Its use and effectiveness depends on patient considerations, the extent and duration of the procedure, the choice of drug and technique, and the skill and experience of the practitioner. INTRODUCTION Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

6. Alcohol is the oldest known sedative. It was used in the ancient Mesopotamia thousands of years ago. 3400 B.c -The ‘Euphoric’ effect of Opium was discovered by Summerians . Joseph Priestly(1733-1804)- discovered various gases like- nitrous oxide, ammonia, oxygen. HISTORY Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

7. 1801-Humphry Davy - Anesthetic properties of nitrous oxide. -Coined the term ‘laughing gas ’. Dec 10,1844- Sir Horace Well attended lecture on ‘Chemical Phenomenon’ by Gardner.(nitrous oxide) HISTORY Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

8. Dec 11,1844, Nitrous oxide was administered to Dr. Horace Well, rendering him unconcious & able to have wisdom tooth extracted without awareness of pain. HISTORY T. Y. Euliano,J . S. Gravenstein , Essential Anesthesia -From Science to Practice:United States of America by Cambridge University Press, New York;2004: Introduction A very short history of anesthesia;p.1-4

9. 16 th oct , 1846, ether was administered by Sir William Morton for the removal of mandibular tumor . Experiment was published in Boston daily journal. And led to the discovery of Surgical anesthesia . HISTORY

10. 1850’s Cocaine isolated, hypodermic needle developed 1853 Chloroform used as anesthetic by Dr.John Snow Chloroform being used as anesthesia HISTORY T. Y. Euliano,J . S. Gravenstein , Essential Anesthesia -From Science to Practice:United States of America by Cambridge University Press, New York;2004: Introduction A very short history of anesthesia;p.1-4

11. 1884 Carl Koller introduces cocaine into medical practice 1884 Halsted injected cocaine directly into mandibular nerve and brachial plexus Carl Koller (1857 -1944) William Halsted HISTORY T. Y. Euliano,J . S. Gravenstein , Essential Anesthesia -From Science to Practice:United States of America by Cambridge University Press, New York;2004: Introduction A very short history of anesthesia;p.1-4

12. 1905 Procaine synthesized by Einhorn 1948 First amide L.A (Lidocaine) synthesized by Lofgren 1960 Mepivacaine 1983 Bupivacaine 2000 Articaine HISTORY Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

13. DEFINITION Loss of pain sensation over a specific area of the anatomy without loss of consciousness but also to the interruption of all other sensations ,including temperature, pressure, and motor function. Bennett Richard C.,Monheim’s Local Anesthesia and Pain Control in Dental Practice 7 th edition page no.2,CBS publishers and distributers

14. DEFINITION Local anesthesia is defined as a loss of sensation in a circumscribed area of the body caused by a depression of excitation in nerve endings or an inhibition of the conduction process in peripheral nerves. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

15. MECHANISM OF ACTION OF LOCAL ANESTHESIA SURFACE CHARGE THEORY http://cnx.org/resources/09ab17c9199ed6fb925c5fae201df4bcfac9b846/Figure_35_02_01.jpg

16. MECHANISM OF ACTION OF LOCAL ANESTHESIA MEMBRANE EXPANSION THEORY http://cnx.org/resources/09ab17c9199ed6fb925c5fae201df4bcfac9b846/Figure_35_02_01.jpg

17. MECHANISM OF ACTION OF LOCAL ANESTHESIA MEMBRANE EXPANSION THEORY Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

18. MECHANISM OF ACTION OF LOCAL ANESTHESIA Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier. SPECIFIC RECEPTOR THEORY

19. RNH + == ==  RN+ H + low pH RNH + > RN + + H + high pH RNH + < RN + H + Henderson Hasselbalch equation Log base/acid = pH - pKa DISSOCIATION OF LOCAL ANESTHETICS Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

20. Mechanism of action of L.A molecule. Anesthetic pKa of 7.9; tissue pH of 7.4 Effect of decreased pH on action of L.A Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier. CLINICAL IMPLICATIONS

21. Factor Action affected Description pKa Onset Lower pKa = more rapid onset of action, more uncharged molecules present to diffuse through nerve sheath. Lipid solubility Anesthetic potency Increased lipid solubility = increased potency Protein binding Duration Increased protein binding allows anesthetic cations to be more firmly attached to protein located at receptor sites, thus duration of action is increased Non-nervous tissue diffusibility Onset Increased diffusibility = decreased time of onset Vasodilator activity Anesthetic potency and duration Greater vasodilator activity = increased blood flow to region = rapid removal of anesthetic molecules from injection site, thus decreased anesthetic potency and decreased duration FACTORS AFFECTING LOCAL ANESTHETIC ACTION

22. CLASSIFICATION A) BASED ON DURATION OF ACTION: 1) Ultra Short acting anesthetics (less than 30 mins ) 2) Short acting anesthetics(45 to 75 mins ) 3) Medium acting anesthetics (90-150 mins ) 4) Long acting anesthetics (180 mins or longer) Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

23. B)SURFACE ANESTHETICS: 1)Soluble agents- E.g. Cocaine, Lidocaine, Tetracaine 2)Insoluble agents- E.g. Benzocaine, Oxethazine CLASSIFICATION Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

24. C) BASED ON BIOLOGICAL SITE 1) CLASS A- Agents acting at receptor site on external surface of nerve membrane. E.g. Biotoxins 2) CLASS B- Agents acting at receptor sites on internal surface of nerve membrane. E.g. lidocaine CLASSIFICATION Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

25. CLASSIFICATION Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

26. 3) CLASS C- Agents acting by a receptor independent, physicochemical agents. E.g. Benzocaine . 4) CLASS D- Agents acting by combination of receptor and receptor independent mechanisms. E.g. Articaine , Prilocaine . CLASSIFICATION Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

27. Based on the chemistry Esters Amides Quinilones e.g. Articaine e.g. centbucridine Lidocaine Bupivacaine Mepivacaine , prilocaine Benzoic Paraaminobenzoic e.g. Butacaine e.g. Procaine Cocaine Cloroprocaine Benzocaine Propoxycaine Tetracaine Piperocaine

28. PHARMACOLOGY UPTAKE Degree of vasoactivity Vasodialating properties. Procaine is a potent vasodialator . Cocaine - only L.A having vasoconstriction action Vasodilatation -  the rate of absorption of L.A. into the blood -  duration and depth of anesthesia. Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

29. ORAL ROUTE Except cocaine , L.A are absorbed poorly , if at all from the G.I. tract 72% OF drug undergoes significant hepatic first pass effect. TOPICAL ROUTE Applied to intact skin- No anesthetic action. Damaged or sunburn skin- anesthetic effect EMLA-can be used on intact skin PHARMACOLOGY Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

30. INJECTION Rate of uptake after s.c ., i.m ., or i.v ., is related to the vascularity at the site of injection and vasoactivity of the drug. I.V administration of L.A., is used for the management of ventricular dsyrhythmias PHARMACOLOGY ROUTE TIME TO PEAK LEVEL (MIN) INTRAVENOUS 1 TOPICAL 5 INTRAMUSCULAR 5-10 SUBCUTANEOUS 30 - 90 Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

31. DISTRIBUTION Plasma conc. Of local anasthetics have significant effect on potential toxicity of the drug. PHARMACOLOGY Blood level of anaesthetics depends on- 1.Rate at which drug is absorbed into CVS. 2. Rate of distribution of drug from vascular compartment to tissues. 3.Elimination of drug through metabolic or excretory pathway. Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

32. Esters - Hydrolyzed in plasma by enzyme Pseudocholinesterase Procaine hydrolyzed by pseudo cholinesterase's Para amino benzoic acid Diethylamine Excreted unchanged urine further transformed-urine Atypical Pseudocholinesterase PHARMACOLOGY Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

33. Amide Mostly gets metabolised in Liver Relative contraindication for patient with liver dysfuction . PHARMACOLOGY Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

34. EXCRETION KIDNEYS Esters readily undergo biotransformation-small conc. in urine as parent compound compared to amide. Renal impairment- Relative contraindication PHARMACOLOGY Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

35. COMPOSITION Local anesthetic drug – eg lignocaine . 21.3 mg/ml Vasopressor drug - eg adrenaline.1:80,000, 1:20,0000 Reducing agent - eg Sodium meta bi sulfide. 0.4-0.5mg Preservative – eg Methyl paraben.0.1% For isotonicity – Normal Saline . 6mg Diluting agent – Distal water Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

36. SYSTEMIC EFFECTS CNS Easily crosses blood brain barrier. Causes CNS depression at low doses. Blood level Effect 0.5-4 μ g/ml - Anticonvulsant action, direct depression Increase in seizure threshold. 4.5-7 μ g/ml - Preseizure signs and symptoms caused by depression of inhibitory neuron > 7.5 μ g/mi - Tonic clonic seizure. entire blokage of inhibitory neuron. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

37. CVS Causes myocardial depression. Produces peripheral vasodialation and hypotension. Maximum dose- 4.4 mg/kg body weight (plain) 7 mg/kg body weight (with adrenaline) Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier. SYSTEMIC EFFECTS

38. RESPIRATORY SYSTEM Dual effect. Low doses- direct relaxant action on bronchial smooth muscles. High doses- Respiratory arrest as a result of CNS depression Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier. SYSTEMIC EFFECTS

39. 39 Notes Main unwanted effects Plasma half-life Tissue penetration Duration Onset Drug Rarely used, only as spray for upper respiratory tract Cardiovascular and CNS effects due to block of amine uptake ~1h Good Medium Medium Cocaine No longer used CNS: restlessness, shivering, anxiety, occasionally convulsions followed by respiratory depression CVS: bradycardia and decreased cardiac output, vasodilatation, which can cause cardiovascular collapse <1h Poor Short Medium Procaine (2-4%) Widely used for local anaesthesia .Also used i.V . For treating ventricular arrhythmias mepivacaine is similar Less tendency to cause CNS effects ~2h Good Medium Rapid Lignocaine (lidocaine) (2%) Widely used because of long duration of action. Ropivacaine is similar, with less cardiotoxicity As lingocaine , but greater cardiotoxicity ~2h Moderate Long Slow Bupivacaine (0.5%) Widely used, not for obstetric analgesia because of risk of neonatal methaemoglobinaemia No vasodilator activity, can cause methaemoglobinaemia ~2h Moderate Medium Medium Prilocaine Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

40. TOPICAL ANAESTHESIA Insoluble in water- soluble in vehicle such as alcohol, polyethylene glycol, propylene glycol, or carboxymethyl cellulose – can be used for surface application Advantage 1. By incorporating the anesthetic into a viscous liquid, a gel, or an ointment, they remain in contact with the area for a longer period, thereby increasing the duration of action. 2. poorly absorbed into the circulation, Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

41. BENZOCAINE Poor solubility in water Poor absorption into CVS Remains longer at the site of application Prolonged use – localized allergic reaction Availability as: Aerosol, Gel, Gel patch, Ointment , Solution Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier. TOPICAL ANAESTHESIA

42. EMLA Cream (Lidocaine 2.5% + Prilocaine 2.5%) Emulsion in which oil phase is eutectic mix of lidocaine and prilocaine in a ratio of 1:1 by wt Supplied as 5g or 30 gm tube or as an EMLA disc. Can be used to provide surface anesthesia o intact skin. Contraindicated-pts with congenital idiopathic methhemogloulinemia . TOPICAL ANAESTHESIA Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

43. LIGNOCAINE Lidocaine base- poorly soluble in water-5%, used on ulcerated,abraded and lacerated wound. Lidocaine hydrochloride- water soluble -2%. Aerosol spray, gel, ointment, patch, solution. Topical form-20mg/ml TOPICAL ANAESTHESIA Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

44. CONTRINDICATIONS ABSOLUTE Local anaesthetic allergy Bisulfite allergy RELATIVE Atypical plasma cholinesterase Methemoglobinemia Significant cardiovascular, liver or renal disease. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

45. VASOCONSTRICTOR Need for vasoconstrictor ↑ absorption of L.A into CVS → removal from injection site Rapid diffusion of L.A from inj site → ↓ duration of action & depth of anesthesia. Higher plasma level of L.A → ↑ risk of toxicity ↑ bleeding at inj site. Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

46. Addition of vasoconstrictor Constriction of blood vessels → ↓ tissue perfusion Slow absorption into CVS → low anesthetic blood level → ↓ risk of toxicity. Higher volume of L.A around nerve → ↑ duration of action ↓ bleeding at inj site VASOCONSTRICTOR Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

47. Adrenergic system- α and β receptors. β - β 1 and β 2 α – α 1 and α 2 β 1 - Heart β 2 - Vascular beds of skeletal muscle and pulmonary vasculature. α 1 - peripheral vasculature. α 2 - CNS SYSTEMIC EFFECTS Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

48. Vasoconstrictor Β 1 selectivity Β 2 selectivity Relative α potency Epinephrine 50% 50% 100% Norepinephrine 85% 15% 25% Levonordefrin 75% 25% 15% Phenylephrine 95% 5% 5% SYSTEMIC EFFECTS Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

49. CLINICAL ASPECTS Max dose of lidocaine without adrenaline is = 300mg Max dose of LA with adrenaline = 500mg Max safe dose of adrenaline =0.2mg/visit 2% Lignocaine= 2g in 100 ml 2000mg in 100 ml 20 mg in 1ml - 1 mg= 1/20 500mg=1/20 500= 25ml can be given safely for a normal pt Adrenaline present in our vials is in conc. of 1:200,000 1ml=1/200,000=0.005mg 0.005mg-1ml As MRD-0.2mg , so for normal pt- 0.2 mg=1/0.005 0.2= 40ml of LA can be administered safely

50. COMPLICATIONS LOCAL SYSTEMIC Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

51. [A] LOCAL COMPLICATIONS:- Needle breakage Pain on injection Burning on injection Parasthesia or persistent anesthesia Trismus Hematoma Infection Sloughing of tissues Soft tissue injury Facial nerve paralysis Post anesthetic intra-oral lesions Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

52. B. Systemic Drug allergy Toxicity Cvs and respiratory complications Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

53. 1.Needle breakage Use of larger needles for nerve blocks. Use longer needles when sufficient depth injections are to be given. As hub is the weakest part, avoid inserting a needle into the tissues to its hub. Do not redirect the needle, instead withdraw almost completely and then redirect it. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

54. 2. PAIN ON INJECTION Proper technique. Usage of topical anesthesia. Slowly injecting local anesthetic. Correct temperature of L.A. Management: No Management generally required only reassurance is given to the patient. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

55. 3. BURNING ON INJECTION: pH of solution. Rapid injection of L.A. to adherent tissues like palate. Contamination of local anesthetic solution. Warmed solution. Prevention: Slowing of injection should help. Ideal rate : 1 ML per minute. Max. rate : 1.8 ML per minute. Storage of solution at room temperature. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

56. 4. TRISMUS Cause: Most common : Trauma to muscles or blood vessels in infratemporal fossa . Usually, injury to medial pterygoid muscles, also superior constrictor of pharyna and masseter muscles can cause trismus . L.A. into which alcohol or cold sterilizing solutions have diffused, may produce irritation and cause this problems. The injection of L.A. either intramuscularly or supramuscularly lead to rapidly progressive necrosis of exposed muscle fibres . Haemorrhage . Low grade infection. Multiple needle penetration at the same site. Excessive volumes of solution deposited in a restricted area produces distention causing trismus . Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

57. Prevention: Use of sharp, sterile, disposable needles. Proper care for and handle dental L.A. cartridges. Use aseptic technique. Practice atraumatic insertion and injection technique. Use minimum effective volumes of solution. Avoid repeat injections and multiple insertion in the same area. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

58. Management: Heat Therapy Warm saline rinse Analgesics: Muscle relaxant Ph ysiotherapy consisting of opening and closing the mouth as well as lateral exursion of mandible Complete recovery : About six weeks(range: 4-20 weeks) Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

59. 1. Toxicity Too large dose of local anesthetic drug Unusually rapid absorption of the drug Accidental intravenous injection High concentration of drug Unusually slow biotransformation Slow elimination Injection of solution In highly vascular area without the addition of vasoconstrictor Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

60. Early symptoms On cerebral cortex Talkativeness Restlessness Apprehension disorientation Tremors of hands and feet On Medulla Lethargy Sleepiness Drowsiness Muscular weakness Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

61. Late symptoms On cerebral cortex Increased blood pressure Increased pulse rate Increased respiratory rate Generalized seizure On medulla Decrease blood pressure Decrease pulse rate Decease heart rate Respiration depression Unconsciousness Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

62. Cortical depression Unresponsiveness Unconsciousness Stupor coma Medullary depression Depression of cardiovascular function Respiratory depression hypoxia Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

63. Prevention Pre analgesic evaluation of the patient Use the weakest possible concentration of drug Use vasoconstrictor whenever possible Use of least possible volume Aspirate before injection Slow injection Monitor the patient carefully after injection Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

64. In slow onset (5min after administration) - Position (supine with feet elevated slightly) -Assess and maintain airway -Assess breathing -Assess circulation -Definitive care Reassure the patient Oxygen administration to prevent acidosis Monitor and record vital signs Diazepam administered slowly intravenously (5mg/min) Treatment Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

65. In severe overdose reaction (rapid onset) - Position (supine with feet elevated slightly) -Assess and maintain airway -Assess breathing -Assess circulation -Definitive care in the presence of tonic clonic seizure 1.Protect patient’s arms ,legs and head.Loosen tight clothing. 2.Administer oxygen 3. Administer anticonvulsant –IV Diazepam at rate 5mg/min or midazolam 1mg/min. Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

66. Postseizure ( postictal ) phase - Position (supine with feet elevated slightly) -Assess and maintain airway -Assess breathing -Assess circulation -Definitive care 1.Administer IV fluids 2.Allow the patient to rest until recovery Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

67. Drug Allergy may be defined as a specific type of hypersensitivity to drug or chemical compound brought about by an alteration in the body’s reaction to an antigenic substance. 2. Allergy Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

68. Type Mechanism Principle Antibody Or cell Time of reaction Clinical examples I Anaphylaxis (Immediate, Homocytochromic , antigenic induced , antibody mediated) IgE Sec to min -Anaphylaxis -Atopic bronchial asthma -Allergic rhinitis - Urticaria - Angioedema -Hay fever II Cytotoxic ( antimembrane ) IgG IgM - -Transfusion reaction -Autoimmune hemolysis -Hemolytic anemia -Certain drug reaction III Immune complex(Serum sickness like) IgG 6-8 hrs -Membranous glomerulonephritis -Serum sickness -Acute Viral hepatitis Classification of allergic diseases Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

69. Type mechanism Principle antibody Time of reaction Clinical examples IV Cell mediated (delayed) or Tuberculin type response - 48 hrs -Allergic contact dermatitis -Infectious granulomas (tuberculosis ,mycoses) -Tissue graft rejection -Chronic hepatitis Classification of allergic diseases Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

70. 1. Early phase –Skin reactions Pt complains of feeling sick Intense itching Flushing( erythema ) Urticaria over the face and upper chest Angioedema 2. GI disturbances related to smooth muscle spasm Severe abdominal cramps Nausea and vomiting Diarrhea Typical Reaction Progression of Generalized Anaphylaxis

71. 3. Respiratory Symptoms Respiratory distress Dyspnea Wheezing Flushing Cyanosis Perspiration Tachycardia Possible laryngeal edema 4. Cardiovascular system Pallor Lightheadedness Tachycardia Hypotension Cardiac dysrhythmias Unconsciousness Cardiac arrest Typical Reaction Progression of Generalized Anaphylaxis Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

72. Recognize problem ( itching, hives, edema,flushed skin) Discontinue dental treatment Activate office emergency team P –Position patient comfortably A-B-C-Assess and perform basic life support as needed Activate emergency medical service if recovery not immediate D- Provide definitive management as needed In more generalized slow onset skin reaction Observe patient Administer oral Administer IM or IV +oral histamine blocker histamine blocker every 4-6 hrly 50 mg diphenhydramine or 10mg Chlorpheniramine Medical consultation prior to future dental care Management of delayed onset ,allergic skin reaction Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

73. Recognize problem ( itching, hives, edema,flushed skin ,conjunctivitis ,Rhinitis) Discontinue dental treatment Activate office emergency team P –Position patient comfortably A-B-C-Assess and perform basic life support as needed Activate emergency medical service if recovery not immediate D- Provide definitive management as needed management of more rapid onset allergic reaction is predicted on presence or absence of signs of respiratory or cardiovascular involvement (Monitor vital signs) (no CVS or respiratory involvement) (CVS or respiratory involvement) Administer Oral or IM Histamin blocker (50 mg diphenhydramine or P-reposition patient 10 mg chlorpheniramine Allow recovery and discharge patient Management of rapid onset ,allergic skin reaction

74. CVS involvement No CVS involvement Hypotension Supine position with legs elevated Comfortable Administer Oxygen Administer 0.3 ml epinephrine IM every 5-20 min .as needed to a total of 3 doses. Summon medical assistance Administer histamine blocker 50 mg diphenhydramine (IM) Permit recovery and discharge of patient Malamed F Stanley,pg-1,Chapter I, Neurophysiology, Handbook of local anesthesia,Sixth edition,2013, An imprint of Elsevier.

75. FUTURE DIRECTION OF LOCAL ANESTHETICS

76. BUFFERED LOCAL ANESTHESIA Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

77. MICROPARTICULATE FORMULATIONS Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier

78. REVERSAL OF LOCAL ANESTHESIA Formulation of phentolamine mesylate ( OraVerse ) a-adrenergic antagonist 1.7 ml cartridges containing 0.4 mg phentolamine mesylate . Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

79. ELECTRONIC DENTAL ANESTHESIA Joseph A et al,pharmacology of Local Anesthetics used in oral surgery , Anesthesia:Oral and Maxillofacial clinics of North America; Volume 25, Issue 3, Pages 453-466 (August 2013)  

80. Fonseca J Raymond,Chapter 3; Local aneasthetics,Vol 1: Anesthesia and pain control, Dentoalveolar Surgery, Practice Managment , Implant Surgery, oral and maxillofacial Surgery,pg - 35-55,vol 1,2 nd edition,2009, Saunders, Elsevier ELECTRONIC DENTAL ANESTHESIA

81. SINGLE TOOTH ANESTHESIA/COMPUDENT Orrett E. Ogle,et al Advances in Local Anesthesia in Dentistry Dent Clin N Am 55 (2011) 481–499

82. INTRAOSSEOUS INJECTION, STABIDENT Orrett E. Ogle,et al Advances in Local Anesthesia in Dentistry Dent Clin N Am 55 (2011) 481–499

83. SUMMARY Local anesthesia remains the foundation of pain control in dentistry especially when combined with moderate-deep sedation for invasive and painful procedures in the contemporary oral and maxillofacial surgical model. Dentistry has never had the choice of local anesthetic drugs and techniques that can be tailored to individual patients and procedures as are available today

84. Local anesthetics remain the safest and most effective drugs in medicine and dentistry to relieve introperative and postoperative pain. It is only with a through understanding of pharmacology and anatomy that clinicians have the basic clinical foundation to enhance the care of patients. SUMMARY

85. THANK YOU…..!!!!!