LOCAL ANAESTHESIA classification, contents , indication and contraindication

local anesthesia

1. LOCAL ANAESTHESIA PRESENTED BY Tanya kohli PG 1 st year GUIDED BY Dr. Anurag Jain Dr. Sonal Bansal Dr. Saurabh Mankeliya

2. CONTENTS 1.INTRODUCTION 2. HISTORY 3.PROPERTIES OF LA 4. CLASSIFICATION 5. LIDOCAINE 6. THEORIES OF LA 7. COMPOSITION 8.PHARMACO-KINETICS 9 .VASOCONSTRICTOR AND ITS CLASSIFICATION 10. TECHNIQUES OF LA 11. COMPLICATIONS OF LA 12. MANAGEMENT OF COMPLICATIONS 13. RECENT ADVANCES OF LA

3. INTRODUCTION ANAESTHESIA – GREEK - meaning AN means NOT and AESTHESIA means SENSATION Coined in 1846 by OLIVER WENDELL HOLMES, in a letter to dentist WILLIAM T. G. MORTON, the first practioner to publicly the use of ether during surgery OLIVER WENDELL HOLMES WILLIAM T. G. MORTON

4. Local Anaesthesia is defined as a transient reversible 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 STANLEY F. MALAMED

5. A Local Anaesthetic is a drug that causes reversible local anaesthesia and a loss of nocioception when it is used on a specific nerve pathways (nerve block), effects such as analgesia and paralysis can be achieved Local anaesthetics are alkaloid bases with acids which give water soluble salts Water solubility is essential as it determines its diffusion through the interstitial fluids to the nerve fibers

6. Pain and dentistry are often synonymous in the minds of patients, especially those with poor dentition due to multiple extractions, periodontal disease requiring surgery, or symptomatic teeth requiring endodontic therapy. The everyday practice of dentistry is therefore based upon achieving adequate local anesthesia. Members of the public perceive a good dentist as a practitioner who causes little or no discomfort the fear of pain associated with dentistry is closely associated with the most common method for blocking pain during dental procedures- intraoral administration of local anesthetics . Members of the public perceive a good dentist as a practitioner who causes little or no discomfort

7. HISTORY The motto behind discussing history is to prove that how important it has always been to provide a painless treatment. Different eras had different methods of achieving local anesthesia. The first attempts at a state of anesthesia were probably herbal remedies administered in prehistory. Alcohol is the oldest known sedative. Use of a combination of poppy and hyocyamus by ancient Egyptians. The main motive was to provide a painless procedure – relief from pain.

8. Ancient Incas - first to discover the fatigue- chasing and mood elevating effects of ERYTHROXYLUM COCA ( coca shrub ) Leaves were chewed by them and spat on wounds and sites to be operated upon to bring about anesthetic effect in that region. Many attempts were hence, made to isolate the cerebral stimulating ingredient from the coca bush

9. COCAINE -first local anesthetic agent isolated by NIEMAN -1860 from the leaves of the coca tree. Its anesthetic action was demonstrated by KARL KOLLER in 1884. It was Frued and his colleague Karl Kollar who first noticed its anesthetic effect. Kollar first introduced it to clinical ophthalmology as a topical ocular (eye) anesthetic .

10. First effective and widely used synthetic local anesthetic - PROCAINE -produced by EINHORN in 1905 from benzoic acid & diethyl amino ethanol. The first synthetic local anesthetic was procaine, better remembered today by its trade name, "Novocain Novocain was not without its problems.  It took a very long time to set (i.e.. to produce the desired anesthetic result), wore off too quickly and was not nearly as potent as cocaine.  On top of that, it is classified as an ester.  Esters tend to have a very high potential to cause allergic reactions

11. LIDOCAINE- LOFGREN in 1948. The discovery of its anesthetic properties was followed in 1949 by its clinical use by T. GORDH. Thereafter, series of potent anesthetic soon followed with a wide spectrum of clinical properties .

12. DESIRABLE PROPERTIES OF LOCAL ANESTHESIA It should not be irritating to tissue to which it is applied It should not cause any permanent alteration of nerve structure . Its systemic toxicity should be low . Time of onset of anesthesia should be short It should be effective regardless of whether it is injected into the tissue or applied locally to mucous membrane. The duration of action should be long enough to permit the completion of procedure.(yet not so long as to require an extended recovery)

13. In addition to these qualities,BENNET lists other desirable properties of ideal L.A It should have the potency sufficient to give complete anesthesia without the use of harmful concentration solutions. It should be free from producing allergic reactions It should be stable in solution and relatively undergo biotransformation in the body. It should be either sterile or be capable of being sterilized by heat with out deterioratio n.

14. CLASSIFICATION Esters – Benzoic acid Para Amino benzoic Cocaine Procaine Benzocaine Propoxycaine Hexylcaine Chloroprocaine Tetracaine Amides – Articaine Bupivacaine Dibucaine Lignocaine Mepivacaine Prilocaine procinamide Based on intermediate group --

15. Class A Class B Class C Class D Agents acting at receptor site –external surface eg Biotoxin - tetrodotoxin .Agents acting at receptor site- internal surface.. Eg Quaternary amonium -scorpion venom Agents acting at receptor independent physico chemical mechanism. Benzocaine Agents acting in combination of receptor and independent mechanism . Clinically useful agents –Lignocaine etc,most of LA According to biological site and mode of action—

16. LIDOCAINE Lidocaine, Xylocaine or lignocaine is a common local anesthetic and antiarrhythmic drug. Most widely used LA effective by all routes. Faster onset . Available as Injections, topical solution, jelly and ointment etc Lidocaine is used topically to relieve itching, burning and pain from skin inflammations, injected as a dental anesthetic or as a local anesthetic for minor surgery. More intense, longer lasting, than procaine.

17. Sets on quickly and produces a desired anesthetic effect for several hours Good alternative for those allergic to ester type More potent than procaine but about equal toxicity It relieves pain during the dental surgeries Quicker CNS effects than others

18. Sets on quickly and produces a desired anesthetic effect for several hours Good alternative for those allergic to ester type More potent than procaine but about equal toxicity It relieves pain during the dental surgeries Quicker CNS effects than others Anti arrhythmic Cause little allergenic reaction; it is hypoallergenic

19. uses USE : a) 2% lignocaine with 1: 50000 epi. – hemostasis b) 2% lignocaine with 1: 100000 or 1: 200000 – local anesthesia COMPARISON OF LIDOCAINE WITH PROCAINE – More rapid onset of action More profound anesthesia Longer duration of action Greater potency

20. THEORIES MECHANISM OF ACTION OF LOCAL ANESTHETICS Many theories have been promulgated over the years to explain the mechanism of action of local anesthetics. ACETYLCHOLINE THEORY: Stated that acetylcholine was involved in nerve conduction in addition to its role as a neurotransmitter at nerve synapses. There is no evidence that acetylcholine is involved in neural transmission.

21. CALCIUM DISPLACEMENT THEORY States that local anesthetic nerve block was produced by displacement of calcium from some membrane site that controlled permeability of sodium .

22. SURFACE CHARGE (REPULSION) THEORY Proposed that local anesthetic acted by binding to nerve membrane and changing the electrical potential at the membrane surface. Cationic drug molecule were aligned at the membrane water interface, and since some of the local anesthetic molecule carried a net positive charge, they made the electrical potential at the membrane surface more positive, thus decreasing the excitability of nerve by increasing the threshold potential. Current evidence indicate that resting potential of nerve membrane is unaltered by local anesthetic.

23. MEMBRANE EXPANSION THEORY It states that local anesthetic molecule diffuse to hydrophobic regions of excitable membranes, producing a general disturbance of bulk membrane structure, expanding membrane, and thus preventing an increase in permeability to sodium ions. Lipid soluble LA can easily penetrate the lipid portion of cell membrane changing the configuration of lipoprotein matrix of nerve membrane. This results in decreased diameter of sodium channel, which leads to inhibition of sodium conduction and neural excitation .

24. SPECIFIC RECEPTOR THEORY : The most favored today, proposed that local anesthetics act by binding to specific receptors on sodium channel the action of the drug is direct, not mediated by some change in general properties of cell membrane. Biochemical and electrophysiological studies have indicated that specific receptor sites for local anesthetic agents exists in sodium channel either on its external surface or on internal axoplasmic surface

25. COMPOSITION LOCAL ANESTHETIC AGENT (DRUG) (xylocaine, lignocaine 2%) -Blockade of nerve conduction. VASOCONSTRICTOR (adrenaline 1: 80,000) Increase depth and increase duration of anesthesia ; decreases aborption of local anesthetic . SODIUM METABISULPHITE - reducing agent (antioxidant) METHYL PARABEN,CAPRYL HYDROCUPRIENOTOXIN - Bacteriostatic agent T HYMO L -Fungicide VEHICLE (DISTILLED WATER and NACL) Volume and Isotonicity of solution Nitrogen bubble- to avoid entrapment of oxygen

26. The chemical characteristics are so balanced that they have both lipophilic and hydrophilic properties. If hydrophilic group predominates, the ability to diffuse into lipid rich nerves is diminished. If the molecule is too lipophilic it is of little clinical value as an injectable anesthetic, since it is insoluble in water and unable to diffuse through interstitial tissue .

27. VASOCONSTRICTORS • Decrease blood flow • Lower anesthetic blood levels • Decrease the risk of toxicity • Increases duration of action • Decrease bleeding

28. VASOCONSTRICTORS CLASSIFICATION CATECHOLAMINES – Epinephrine – Norepinephrine – Dopamine – Levonordefrin – Isoproterenol

29. EPINEPHRINE Maximum Dose for Dental Appointment - Normal healthy patient: 0.2 mg. per appointment - Significant cardiovascular impairment: 0.04 mg per appointment NOREPINEPHRINE Maximum dose : Healthy pt – 0.34 mg per appointment or 10 ml of 1:30000 solution pt. with CV disease : 0.14 mg per appointment or 4 ml of 1:30000 solution

30. FACTORS IN SELECTION OF A LA FOR A PATIENT 1. Length of time pain control is necessary. 2. Potential need for post treatment pain control 3. Possibility of self-mutation in the postoperative period 4. Requirement for haemostasis 5 . Presence of any contraindication to the LA solution selected for administration

31. COMMON QUESTIONS TO ASK THE PATIENT Allergic to any medications? Have you ever had a reaction to local anesthesia? If yes, describe what happened? Was treatment given? If so, what?

32. PREPARATION OF THE PATIENT Careful preoperative assessment History A clear explanation of what to expect

33. Data should be documented includes: *.Baseline vital signs: 1.blood pressure 2.laboratory values 3.Results of ECG monitoring 4.any other tests *. Weight, height, and age: Dosage of some drugs is calculated on the basis of body weight in kilograms (mg/kg). Some drugs are contraindicated for age extremes (i.e., pediatric or geriatric patients).

34. Current medical problem(s) past history of medical events, including a history of substance abuse Current medications or drug therapy, such as insulin for diabetes or hypertensive drugs. Allergy, or hypersensitivity reactions to previous anesthetics or other drugs Mental status, including emotional state and level of consciousness Communication ability A patient with hearing impairment or language barrier may be unable to understand verbal instructions during the procedure or to respond appropriately.

35. STRESS REDUCTION PROTOCOL Morning appointments are usually best. Keep appointments as short as possible. Freely discuss any questions, concerns, or fears that the patient has  Establish a honest, supportive relationship with the patient. Maintain a calm, quiet, professional environment. Provide clear explanations of what the patient should expect and feel

36. Premedicate with benzodiazepines if needed. Ensure good pain control through judicious selection of local anesthetic agents appropriate for treatment. Maintenance of patient comfort throughout the procedure. Use nitrous oxide as needed (avoid hypoxia). Use gradual position changes to avoid postural hypotension .

37. TECHNIQUES OF LOCAL ANAESTHESIA

38. Different techniques of achieving LA Local infiltration Field block Nerve block Intraligamentry Intraseptal Intrapulpal Intraosseous injection Jet injector

39. 1. LOCAL INFILTRATION ( 0.6 – 1.0 ml)small terminal nerve endings are anaesthetized .

40. Computer controlled local anesthetic delivery system Electronic dental anesthesia Topical anesthesia

41. NERVE BLOCK (1.8 – 2.0 ml)depositing the LA solution within close proximity to a main nerve trunk

42. FIELD BLOCK deposited in proximity to the larger nerve branches

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44. Periodontal ligament injection Indications 1. Pulpal anesthesia of one or two teeth in a quadrant 2. Treatment of isolated teeth in mandibular quadrant 3. Patient for whom residual soft tissue anesthesia is undesirable 4. Situations in which regional block is contraindicated Contraindications 1.. Infection or inflammation at the site of injection 2. Primary teeth when the permanent tooth bud is present 3. Patient who requires a “numb” sensation for psychological discomfort

45. Intraseptal injection Indications When both haemostasis & pain control are desired for soft tissue & osseous periodontal treatment Contraindications Infection or severe inflammation at the site of injection

46. Jet injector

47. Principle - based on principle that liquid forced through very small openings, called jets, at very high pressure can penetrate intact skin or mucous membrane The primary use of jet injector is to obtain topical anesthesia before the insertion of a needle In addition it may be used to obtain mucosal anesthesia of palate

48. Advantages 1. Does not require use of needle 2. Delivers very small amount of LA 3. Used in lieu of topical anesthesia

49. Disadvantages Is inadequate for pulpal anesthesia or regional anesthesia 2. May damage periodontal tissue 3. Many patients dislike the feeling accompanying use of the jet injector 4. Post-injection soreness of soft tissue may develop

50. Intraosseous injection Indications Pain control for dental treatment on single or multiple teeth in a quadrant Contraindications Infection or severe inflammation at the site of injection local anesthesia 56

51. Intrapulpal injection local anesthesia Deposition of LA directly into the pulp chamber of a pulpally involved tooth provides effective anesthesia for pulpal extirpation & instrumentation where other techniques have failed.

52. Computer-controlled local anesthetic delivery system The system enables a dentist or hygienist to accurately manipulate needle placement with fingertip accuracy and deliver the LA with a foot-activated control

53. Advantages Precise control of flow rate & pressure, hence a more comfortable injection Increased tactile feel Automatic aspiration Rotational insertion technique minimizes needle deflection Disadvantages Need for additional armamentarium 2. Increased cost

54. Electronic Dental Anesthesia The method of achieving local anesthesia i transcutaneous electrical nerve stimulation {TENS} which has been used for the relief of pain According to the gate control theory of pain, stimulation of large diameter afferents by TENS inhibits nociceptive fiber evoked responses in the dorsal horn

55. Indications In patients with needle phobia Ineffective LA 3. Instances where LA cannot be administered Contraindications Neurological disorders Pregnancy Very young pediatric patients Older patients with senile dementia 5. Cardiac pacemakers

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57. Topical anesthesia Anesthesia obtained by the application of a suitable agent to an area of either the skin or mucous membrane which it penetrates to anesthetize superficial nerve endings Spray Ointments & jelly

58. Maxillary anesthesia More easily obtained then mandibular Most commonly used- infiltration 1.8 ml 2% lidocain Succes rate – 90 to 95 % Onset – 5 to 7 minute Duration = 20 – 30 min. anterior teeth 30- 45 min molars Soft tissue anesthesia is not necessarily related to duration of pulpal anesthesia , pulpal anesthesia dose not last long as soft tissue ones

59. Techniques of Injection Basic points- Use a Sterile Sharp Needle Check The flow of Solution Position the patient Dry the tissue/ wipe once. Apply topical anesthetic

60. Topical antiseptic /optional Communicate with patient apply firm hand rest Inject few drops of soln , communicate with patient, Advance to the target slowly ,aspirate , inject Withdraw the needle slowly Observe the patient & check for anesthetic symptoms

61. Technique for Maxillary Block Supra periosteal injection : Anaesthetize buccal soft tissue & hard tissue Nerves anaesthetized – large terminal branches I ndication : 1 or 2 teeth need to be anaesthetized / small area

62. Contra-indication : Infection Dense bone covering Target area : Behind apices of tooth Landmarks : Muco-buccal fold Crown & root length

63. Posterior Superior Alveolar Nerve Block Area anaesthetized: Maxillary 3 rd , 2 nd & 1 st molar (except mesio -buccal root of 1 st molar) Bone & periodontium over these Indication: Treatment of 2 or more molars required Supra-periosteal injection – ineffective Acute inflammation

64. Complications : Hematoma – Non visible - pterygoid plexus posteriorly Visible – buccal aspect Accidental mandibular Anaesthesia Orbital contents – anaesthetized accidentally Accidental - parotid gland  facial nerve affected

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66. MIDDLE SUPERIOR ALVEOLAR NERVE BLOCK

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68. ANTERIOR SUPERIOR ALVEOLAR NERVE BLOCK AKA INFRAORBITAL NERVE BLOCK

69. GREATER PALATINE NERVE BLOCK Technically difficult but high success rate 0.45-0.6 ml success rate Profound palatal and soft tissue anesthesia Potentially traumatic but less than nasoplalantine anesthesia

70. NASOPALANTINE NERVE BLOCK AKA INCISIVE NERVE BLOCK

71. Nasopalatine nerve block Areas anaesthetized Anterior portion of Hard palate and over lying structures back to the bicuspid area. Indications Anterior palatal procedures supplementing infraorbital nerve blocks Anaesthesia of nasal septum Landmarks Central incisor & incisive papilla

72. LOCAL INFILTRATION OF PALATE

73. Maxillary nerve block – Extra Oral Areas anaesthetised Anterior temporal & zygomatic region Lower eyelid Side of nose Anterior cheek Upper lip Maxillary teeth / alveolar bone & overlying structures – 1side Hard & soft palate Tonsils – parts of pharynx Nasal septum – floor of nos e Indications Extensive surgery – 1 half of maxilla Others blocks not possible Therapeutic purposes

74. Inferior alveolar nerve block Areas anaesthetised Mandibular teeth upto midline . Body of mandible . Inferior portion of ramus . Buccal periosteum & mucous membrane Lingual soft tissue Anterior 2/3 rd of tongue Indications Multiple mandibular teeth – procedures Buccal / Lingual soft tissue anaesthesia

75. Contraindications Infection / acute inflammation Young children / mentally handicapped Landmarks Coronoid notch Pterygomandibular raphe Occlusal plane of posterior mandibular teeth Complication Hematoma Trismus Transient facial paralysis (parotid gland)

76. Anatomical structures - final position Superiorly – Inferior alveolar nerves & vessels Insertion of medial pterygoid Mylohyoid nerves & vessels Anteriorly – Deep part of parotid gland Laterally – Lingual nerve Internal pterygoid Spehnomandibular ligament Medially- ramus of mandible . local anesthesia 107

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78. Closed mouth/ Akinosis technique (1977)— Nerves anesthetized - Area anesthetized one half of mandible upto mid line including lingual tissue and inferior portion of the ramus of the mandible. Land mark- occluding plane of the teeth. Muco gingival junction maxillary teeth. Antr border of ramus. Orientation of bevel must be oriented away from the bone of mandibulaar ramus (bevel faces toward mid line). More popular now Land marks easy One prick – mandibular, buccal, lingual n anesthetised . Patient more comfortable . local anesthesia 109

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80. Advantage s Atraumatic, pats. with restricted mouth opening. fewer post op complications. Disadvantages Difficult to visualize the path of needle and depth of insertion . Complications hematoma, transient facial n. paralysis . local anesthesia 112

81. Gow gates technique– 1973 (mandibular n. block) Nerves anaesthetised – inferior alveolar, mental, incisive, lingual, mylohyoid, auriculotemporal and buccal . Area –all mandibular hard and soft tissue Upto mid line. Indications - multiple procedures on mandibular teeth, buccal soft tissue anaesthesia from third molar to midline, conventional inf. alv . n. block is unsuccessful. Contraindications – infection or acute inflammation in the area of infection, pats. with restricted mouth opening . local anesthesia 113

82. Landmarks- Extraora l- corner of mouth, lower border of the tragus, intertragic notch I ntraoral – height of injection established by placement of needle tip just below the mesiolingual cusp of max. 2 nd molar, penetration of soft tissue distal to 2 nd molar at the same height. Final position needle is just inferior to condyle and insertion of lateral pterygoid. Gained popularity – single needle penetration, relies on soft tissue landmarks – differ from patient to patient local anesthesia 114

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84. Lingual nerve block – Area anaesthetised – Anterior 2/3 rd tongue, floor of mouth, lingual mucoperiosteum Only used singly to operate on tongue, floor of mouth Buccinator / long buccal nerve block Area anaesthetised – Buccal mucosa & mandibular molar – mucoperiosteum Land marks External oblique ridge, retromolar triangle local anesthesia 116

85. Mental nerve block Areas anaesthetised Lower lip, mucous membrane – anterior to mental foramen Landmarks Mandibular bicuspids Indications Surgery of lower lip or mucous membrane local anesthesia 118

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87. Extra Oral Technique Mandibular nerve Area anaesthetised Temporal region with auricle of ear & external auditory meatus TMJ, salivary glands Anterior 2/3 rd of tongue Mandible – hard & soft tissue – midline Landmarks mid point of zygomatic arch Zygomatic notch Cornoid process of mandible Lateral pterygoid plate local anesthesia 120

88. I ndications When need to anaesthetise entire mandibular nerve Infection / trauma – makes terminal anaestheisa not possible Diagnostic / therapeutic The needle is pointed posteriorly & to a greater depth of 5 cms local anesthesia 121

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90. Mental & Incisive nerve block Area anaesthetised Mandibular hard & soft tissue – labial aspect with lower lip Landmark s Bicuspid teeth, lower ridge of body of mandible Supra & infra orbital notch Pupil of the eye 2 inch 22 gauge needle used & introduced slightly anteriorly & downwards

91. Complications Definition An anaesthetic complication may be defined as any deviation from the normal expected pattern during or after securing regional anaesthesia 2 types Local Systemic local anesthesia 124

92. SYSTEMIC COMPLICATIONS Toxicity Idiosyncracy Allergy Anaphylactoid reaction Syncope local anesthesia 125

93. Transient / permanent Transient – is one that is severe at occurrence – no residual effects Permanent – residual effect; lasts for a life time even though it is mild Complications could be a combination of any of the above mentioned types Majority are either Primary Mild & Transient or Secondary Mild & Transient local anesthesia 126

94. Complications Attributed to solutions – toxicity, allergy, idiosyncrasy, anaphylactoid reaction, local irritation Attributed to technique / needle – syncope, muscle trismus, pain, edema, hematoma local anesthesia 127

95. Needle breakage Cause – Unexpected movement – patient (if patient movement is opposite to path of needle insertion) Multiple used needle Defective manufacture of needles/barbed needles smaller gauge – more likely to break local anesthesia 128

96. Prevention Correct gauge – 25 gauge Long needles – prevent penetration till hub Not to redirect when in tissue Management Patient – not to move – hand in the mouth – mouth open Fragment visible – remove it Fragment not visible – inform patient – not necessary for intervention immediately – Radiograph suggeste d local anesthesia 129

97. Precautions Avoid bony contact Avoid heavy pressure Avoid movement of needle and patient local anesthesia 130

98. Pain on injection Causes – Careless injection technique Multiple used needle Rapid deposition Problems – Pain – patient anxiety – unexpected movements Prevention – Proper technique – sharp needles Enter topical anaesthetics Inject slowly – solution sterilized Check temperature of solution local anesthesia 131

99. Burning on injection Causes Due to pH of solution  5 (LA) – 3 (LA+VC) Rapid injection Contamination Warm solution Problems pH  disappears upon LA action – no residual effect Contaminated solution  other complications – trismus, edema, paraesthesia local anesthesia 132

100. P revention Slow injection – 1ml / minute Cartridge stored at room temperature – away from containers with alcohol / other agents local anesthesia 133

101. Persistent anaesthesia / paresthesia Causes Direct trauma to nerve – bevel of needle LA solution containing neurotoxic substance – alcohol Injection of wrong solution Hemorrhage / infection – near to nerve Problem Persistent anaesthesia – usually rare Biting / thermal / chemical insult – without patient awareness When lingual nerve is involved – taste impaired local anesthesia 134

102. Prevention Proper care & handling of dental cartridge Adherence to injection protocol Management Usually resolve in 8 weeks Periodic recall & check up of patients Persistence – consult neurosurgeon Recall patient every 2 months for check up local anesthesia 135

103. Trismus Definition “difficulty in opening the jaws due to muscle spasm” Causes Trauma – muscle / blood vessel Irritating solution hemorrhage Infection Multiple needle punctures LA have been known to have slight myotoxicity Excessive volume – distension of tissues Problems Pain / hypomobility local anesthesia 136

104. Prevention Use of sharp, sterile, disposable needle Aseptic technique Practice atraumatic methods Avoid repeated injections Use minimum volume Control infection local anesthesia 137

105. Management Heat therapy Warm saline rinses, moist hot packs Analgesics Aspirin, Codeine (30-60mg), muscle relaxants Initial physiotherapy Thrice a day Antibiotic regime Possibility of infection local anesthesia 138

106. Hematoma “ effusion of blood into extra-vascular spaces” Causes Arterial & venous puncture – common in PSA & Inf. Alv . nerve blocks Patients with bleeding disorders Problem Bruise – may / may not be visible extra-orally Complications – pain & trismus Swelling & discoloration Prevention Knowledge of normal anatomy – proper technique Shorter needle – PSA, minimize the number of penetration Discard defective needles- barbed needles local anesthesia 139

107. Management Immediate – apply firm pressure  5-10minutes Inf. Alv . Nr. Block – medial aspect of ramus Infra orbital, Mental, Incisive block – directly over foramen PSA – pressure on soft tissue with finger as posteriorly as tolerated by patient – medial superior direction Patient to be reviewed after 24 hours, advice analgesics, cold application upto 4-6 hours, warm- pack application next day local anesthesia 140

108. Infection Comparitively rare complication Instrument needle solution to be as aseptic as possible Area & operative hands – cleaned Avoid passing needle through infected area Use disposable syringes local anesthesia 141

109. Edema Causes Trauma during injection Infection, hemorrhage Allergy (Angioedema) Injection of irritating solution Problems Pain & dysfunction Airway obstruction local anesthesia 142

110. Prevention Proper care & handling of armamentarium Atraumatic injection technique Complete medical evaluation prior to injection Management Trauma – resolve in few days without therapy Hemorrhage – resolve slowly 7-14 days Allergy – life threatening, airway impairment – basic life support, call medical help, Epinephrine – 0.3mg, Antihistamine, Corticosteroids Total airway obstruction – Tracheostomy / Cricothyroidectomy local anesthesia 143

111. Sloughing of tissue Causes Epithelial desquamation – topical anaesthesia – long time, heightened sensitivity to LA Sterile abscess – secondary to prolonged ischemia – VC in LA  site – hard palate Problems Pain & infection Prevention Topical – for not more than 1-2 minutes VC – minimal concentration in solution local anesthesia 144

112. Management Symptomatic – pain – analgesia Epithelial desquamation – resolve few days Sterile abscess resolve  7-10 days local anesthesia 145

113. Soft tissue injury Causes Trauma occurs – frequently mentally / physically challenged children Primary cause – significantly longer duration of action Problem Pain & swelling Infection of soft tissue Prevention Cotton roll between lip & teeth Patient – guarded against eating / drinking Warning sticker local anesthesia 146

114. Facial nerve paralysis Cause LA solution into parotid gland – usually while giving Inf Alv Nr. Block, Akinosis technique Problem Ipsilateral loss of motor control – Buccinator muscle Inability to raise the corner of Mouth, close Eye lid Prevention Needle tip to contact bone, redirection of needle to be done only after complete withdrawal local anesthesia 147

115. Management Reassure the patient Resolves after action of LA is over Eye patches to the affected – eye drops Contact lenses if any – removed local anesthesia 148

116. Systemic complications Toxicity / toxic overdose “Signs and symptoms that result from an overly high blood level of a drug in various target organs and tissues” Predisposing factors Age – any age Weight – greater the body weight greater is the amount of dose tolerated before overdose reaction Sex – during pregnancy – renal function disturbed – females more affected at this time local anesthesia 149

117. Diseases – hepatic & renal dysfunction reduced breakdown Congestive heart failure – less liver perfusion Genetics – pseudocholinesterase deficient – toxicity - Ester LA

118. Fearful patients – lower seizure threshold for LA Drug factors – Vasoactivity – vasodilation – increase in blood concentration More concentration – greater risk Dose smaller dose should always be preferred Route of Administration – Intravascular – increased toxicity Rate of injection – slower rate preferred Vascularity of injection site – more vascular – greater absorption Presence of Vasoconstrictor – with VC less absorption local anesthesia 151

119. Causes of toxicity – Biotransformation usually slow Drug – slowly eliminated by kidney Too large a total dose Absorption from injection site - rapid Accidental intra-vascular injection Symptoms – CNS – cerebral cortical stimulation – talkative, restless, apprehensiveness, convulsions Cerebral cortical depression – lethargy, sleepiness, unconsciousness Medullary stimulation – increased B.P, Pulse rate, Respiration local anesthesia 152

120. Medullary depression – mild fall in B.P– severe cases drops to 0 , Pulse , Respiration – similar effect Treatment Mild overdose reaction – slow onset reaction – > 5 mins administer Oxygen (prevent acidosis), monitor vital signs, in case of convulsions – anti- convulsants (diazepam/midazolam) Slower onset - >15 mins – same procedure Severe overdose reaction – rapid onset – 1 minute – unconsciousness with or without convulsion, patient in supine position, convulsions – protect hand, leg, tongue, BLS, administer anti-convulsant post seizure – CNS depression usually present local anesthesia 153

121. Idiosyncrasy “It is an adverse response that is neither an overdose nor an allergic reaction” Common cause – some underlying pathology/psychological /genetic mechanism Pyschotherapy may be helpful Treatment – symptomatic ..remember ABC’s! local anesthesia 154

122. Syncope “transient loss of consciousness that is caused due to cerebral ischemia (neurogenic shock)” Anxiety – increased blood supply to muscles, sitting position 2mm Hg, less pressure – cerebral arteries Clinically light headedness, dizziness, tachycardia & palpitation – may further lead to Unconsciousness Treatment – discontinue procedure, supine position, deep breathing, O2 administration if required, BLS local anesthesia 155

123. Allergy “ Hypersensitive state acquired through exposure to a particular allergen reexposure to which produces a heightened capacity to react” Classification of allergic disease ( gell&coomb ) type TYPE MECHANISM CELL TIMEOF REACTION CLINICAL EXAMPLE 1 Anaphylactic IgE Sec to min Anaphylaxis( drug,venom ) 2 cytotoxic(anti- IgG - Transfusion reaction embrane ) 3 Immune complex IgG 6-8hrs serum sickness (serum-sickness) acute viral hepatitis 4 Cell mediated 48hrs allergic contact dermatitis (delayed) chronic hepatitis local anesthesia 156

124. 1 % of all reaction in LA is allergy Incidence of allergy reduced since introduction of Amides Life threatening allergic response rare Predisposing factors Hyper sensitivity to ester more common-procaine Most of patients allergic to methyl paraben Recently allergy to sodium meta bisulfide is also increasing local anesthesia 157

125. PREVENTIONS Ho of allergy to be recorded - itching,swelling,rashs ….. Ho any asthmatic attack to be noted. Dialogue history. Always better to test the patient for allergy before treatment . local anesthesia 158

126. Consultation and allergy testing Refer doubtful cases for allergic test – -Skin test is primary mode of assesing -Intra cutaneous test most sensitive. 0.1ml of solution- forearm Informed consent that includes cardiac arrest and death to be included. I.V infusion to be started and emergency drugs and equipments must be available local anesthesia 159

127. Signs and symptoms of allergy. Dermatological reactions urticaria –wheal and smooth elevated patches, angio oedema —localized swelling Respiratory reactions– broncho spasm- respiratory distress, dysnea , wheezing, flushing, tachycardia etc. Laryngeal edema – type of angio neurotic oedema to the larynx. -Edema upper air way – laryngeal edema - Lower air way affect broncioles - small. local anesthesia 160

128. Management skin reactions- Delayed – non life threatening - oral histamine blockers- 50 mg diphenhidramine or chlorpheniramine 10 mg -6 th hrly 3-4days Immediate reaction—with conjunctivitis, rhinitis,urticaria - vigorous management. 0.3 mg epinephrine. IM/ SC 50 mg diphenhydramine IM medical help summoned. Observe for 60 mins Oral histamine for 3 days local anesthesia 161

129. Terminate dental treatment patient in comfortable position. administer - oxygen 5-6 lts / mns Admn epinephrine/bronchodilator Observe for 60 min , advise anti histamines to prevent relapse. Laryngeal edema- Patient position ,oxygen, broncho-dilator, epinephrine 0.3mmd im / sc , anti histamines iv, steroids . If condition not improving cricothyrotomy - achieve patent air way if necessary give artificial ventilation. local anesthesia 162

130. blocker like diphenhydramine as anesthetic. General anesthesia alternative Patient with confirmed allergy status- if patient allergic to any one type of anesthetic ester / amide use the other. Use histamine thod of pain control – electric anesthesia / hypnosis . local anesthesia 163

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132. RECENT ADVANCES AND FUTURE TRENDS IN PAIN CONTROL

133. Centbucridine Ropivacaine EMLA TENS ( Transcuteneous Electrical Nerve Stimulation) Hyaluronidase Ultra –long acting local anesthetics Sprays Topical gels Intraoral lignocaine patch(dentipatch) Iantophoresis Jet injection Computer controlled system Comfort control syringe Electronic dental anaesthesia Ph alteration