systemic complications. drug actions all drugs produce multiple effects these effects are...
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SYSTEMIC COMPLICATIONSSYSTEMIC COMPLICATIONS
Drug ActionsDrug Actions
All drugs produce multiple effectsAll drugs produce multiple effects
These effects are categorized as:These effects are categorized as:
DesiredDesired
OROR
UndesiredUndesired
General PrinciplesGeneral Principles
No drug exerts a single actionNo drug exerts a single action
No drug is non-toxicNo drug is non-toxic
Potential toxicity is user dependentPotential toxicity is user dependent
Adverse Drug ReactionsAdverse Drug Reactions
Direct extensions of usual effectsDirect extensions of usual effects
Side effectsSide effects
OverdoseOverdose
Local toxic effectsLocal toxic effects
Adverse Drug ReactionsAdverse Drug Reactions
Altered recipientAltered recipient
Disease processDisease process
Emotional disturbancesEmotional disturbances
Genetic aberrationsGenetic aberrations
IdiosyncracyIdiosyncracy
Adverse Drug ReactionsAdverse Drug Reactions
Allergic reactionAllergic reaction
Immediate - anaphylaxisImmediate - anaphylaxis
Delayed - contact dermatitis Delayed - contact dermatitis
OverdoseOverdose
Dose relatedDose related
Systemic distributionSystemic distribution
Extension of pharmalogic effectsExtension of pharmalogic effects
Selective CNS or CVS depressionSelective CNS or CVS depression
Allergic ReactionsAllergic Reactions
Not dose relatedNot dose related
May be systemic or localizedMay be systemic or localized
Unrelated to pharmacological effectsUnrelated to pharmacological effects
Exaggerated immune system responseExaggerated immune system response
Idiosyncracy ReactionIdiosyncracy Reaction
Unexplained by any known mechanism of the Unexplained by any known mechanism of the drug’s actiondrug’s action
Neither overdose nor allergic reactionNeither overdose nor allergic reaction
Unpredictable; treat symptomsUnpredictable; treat symptoms
Predisposition - OverdosePredisposition - Overdose
Patient factorsPatient factors
AgeAge
WeightWeight
SexSex
Medications Medications
Predisposition - OverdosePredisposition - Overdose
Patient factorsPatient factors
DiseaseDisease
GeneticsGenetics
Psychological attitudePsychological attitude
Predisposition - OverdosePredisposition - Overdose
Drug factorsDrug factors
VasoactivityVasoactivity
ConcentrationConcentration
DoseDose
Route of administrationRoute of administration
Predisposition - OverdosePredisposition - Overdose
Drug factorsDrug factors
Rate of injectionRate of injection
Vascularity of siteVascularity of site
VasoconstrictorsVasoconstrictors
Cause of Overdose LevelsCause of Overdose Levels
Total dose is too largeTotal dose is too large
Absorption is too rapidAbsorption is too rapid
Intravascular injectionIntravascular injection
Biotransformed too slowlyBiotransformed too slowly
Eliminated too slowlyEliminated too slowly
BiotransformationBiotransformation
Esters are hydrolyzed in the plasma and liver Esters are hydrolyzed in the plasma and liver by pseudocholinesterase into PABAby pseudocholinesterase into PABA
Amides are biotransformed by microsomal Amides are biotransformed by microsomal enzymes in liverenzymes in liver
EliminationElimination
Both esters and amides are eliminated through Both esters and amides are eliminated through kidney, some in unchanged form eg. kidney, some in unchanged form eg. (lidocaine - 10%)(lidocaine - 10%)
Prilocaine is eliminated by lungsPrilocaine is eliminated by lungs
Excessive DoseExcessive Dose
Maximum dose should be based on:Maximum dose should be based on:
AgeAge
Physical statusPhysical status
WeightWeight
Rapid AbsorptionRapid Absorption
Vasoconstrictors should be used unless Vasoconstrictors should be used unless specifically contraindicatedspecifically contraindicated
Intravascular InjectionIntravascular Injection
Occurrence varies with type of injection:Occurrence varies with type of injection:
Nerve BlockNerve Block % positive aspirate% positive aspirate
Inf. alveolar 11.7Inf. alveolar 11.7
Mental/Incisive 5.7Mental/Incisive 5.7
Post. sup. alv. 3.1Post. sup. alv. 3.1
Ant. sup. alv./ Buccal < 1Ant. sup. alv./ Buccal < 1
PreventionPrevention
Use aspirating syringeUse aspirating syringe
Use needle - 25 ga or largerUse needle - 25 ga or larger
Aspirate in 2 planesAspirate in 2 planes
Inject Inject slowlyslowly
CLINICAL MANIFESTATIONSCLINICAL MANIFESTATIONSofof
OVERDOSE OVERDOSE
Minimal to ModerateMinimal to Moderate
SignsSigns
Talkativeness ApprehensionTalkativeness Apprehension
Slurred speech ExcitabilitySlurred speech Excitability
Stutter EuphoriaStutter Euphoria
Dysarthria NystagmusDysarthria Nystagmus
Muscular twitching / tremors Muscular twitching / tremors
Minimal to ModerateMinimal to Moderate
Signs (cont.):Signs (cont.):
Elevated BP SweatingElevated BP Sweating
Elevated heart rate Nausea/vomitingElevated heart rate Nausea/vomiting
Elevated resp. rate DisorientationElevated resp. rate Disorientation
Failure to follow commands / reasonFailure to follow commands / reason
Lack of response to painful stimuli Lack of response to painful stimuli
Minimal to ModerateMinimal to Moderate
Symptoms:Symptoms:
Restless Visual disturbancesRestless Visual disturbances
Nervous Auditory disturbancesNervous Auditory disturbances
Numbness Metallic taste Numbness Metallic taste
Minimal to ModerateMinimal to Moderate
Symptoms (cont.):Symptoms (cont.):
Light-headed and dizzyLight-headed and dizzy
Drowsy and disorientedDrowsy and disoriented
Losing consciousnessLosing consciousness
Sensation of twitching (before actualSensation of twitching (before actual
twitching is observed)twitching is observed)
Moderate to HighModerate to High
Generalized tonic-clonic seizure activityGeneralized tonic-clonic seizure activity
followed byfollowed by
Generalized CNS depressionGeneralized CNS depression
Depressed BP, heart rateDepressed BP, heart rate
Depressed respiratory rateDepressed respiratory rate
PathophysiologyPathophysiology
Local anesthetics cross blood-brain barrier, Local anesthetics cross blood-brain barrier, producing CNS depression as level risesproducing CNS depression as level rises
eg. eg. LIDOCAINELIDOCAINE
Blood LevelBlood Level Action ProducedAction Produced
< .5 ug/ml - no adverse CNS effects< .5 ug/ml - no adverse CNS effects
0.5-4 ug/ml - anticonvulsant0.5-4 ug/ml - anticonvulsant
4.5-7.5 ug/ml - agitation, irritability4.5-7.5 ug/ml - agitation, irritability
> 7.5 ug/ml - tonic-clonic seizures> 7.5 ug/ml - tonic-clonic seizures
PathophysiologyPathophysiology
Local anesthetics exert a lesser effect on the Local anesthetics exert a lesser effect on the cardiovascular systemcardiovascular system
eg.eg. LIDOCAINE LIDOCAINE
Blood LevelBlood Level Action ProducedAction Produced
1.8-5 ug/ml - 1.8-5 ug/ml - treattreat PVCs, tachycardia PVCs, tachycardia
5-10 ug/ml - cardiac depression5-10 ug/ml - cardiac depression
>10 ug/ml - severe depression,>10 ug/ml - severe depression,
bradycardia, vasodilatation, arrestbradycardia, vasodilatation, arrest
MANAGEMENTMANAGEMENTofof
OVERDOSEOVERDOSE
Mild Reaction -slow onsetMild Reaction -slow onset
Reassure patientReassure patient
Administer O2Administer O2
Monitor vital signsMonitor vital signs
Consider IV anticonvulsantConsider IV anticonvulsant
Allow recovery or get medical help prnAllow recovery or get medical help prn
Get medical consultation, esp. if possibility of Get medical consultation, esp. if possibility of metabolic or renal dysfunctionmetabolic or renal dysfunction
Severe Reaction - rapid onsetSevere Reaction - rapid onset
Stop all treatment Stop all treatment
Place patient in supine position, feet upPlace patient in supine position, feet up
Establish airway, give O2 (BLS)Establish airway, give O2 (BLS)
If convulsions, protect patientIf convulsions, protect patient
Summon emergency medical helpSummon emergency medical help
Consider anticonvulsant drugs, vasopressorsConsider anticonvulsant drugs, vasopressors
Severe Reaction - slow onsetSevere Reaction - slow onset
Stop all treatmentStop all treatment
Establish airway, give O2 (BLS)Establish airway, give O2 (BLS)
Administer anticonvulsantAdminister anticonvulsant
Summon emergency medical helpSummon emergency medical help
Consider vasopressorsConsider vasopressors
Get medical consultation, esp. if possibility of Get medical consultation, esp. if possibility of metabolic or renal dysfunctionmetabolic or renal dysfunction
Vasoconstrictor OverdoseVasoconstrictor Overdose
Clinical manifestations:Clinical manifestations:
Fear, anxietyFear, anxiety
TensenessTenseness
RestlessnessRestlessness
TremorTremor
WeaknessWeakness
Vasoconstrictor OverdoseVasoconstrictor Overdose
Clinical manifestations (cont.):Clinical manifestations (cont.):
Throbbing headacheThrobbing headache
PerspirationPerspiration
DizzinessDizziness
PallorPallor
Respiratory difficultyRespiratory difficulty
PalpitationsPalpitations
Epinephrine OverdoseEpinephrine Overdose
Sharply elevated BP (systolic)Sharply elevated BP (systolic)
Increased heart rateIncreased heart rate
Cardiac tachyarrhythmiasCardiac tachyarrhythmias
Management - v/c overdoseManagement - v/c overdose
Stop dental treatmentStop dental treatment
Sit patient upSit patient up
Reassure patient, administer O2Reassure patient, administer O2
Monitor BP and pulse until fully recoveredMonitor BP and pulse until fully recovered
Allergic ReactionsAllergic Reactions
Type Mechanism Time Clinical Example Type Mechanism Time Clinical Example
I Antigen induc. sec/min Angioedema,I Antigen induc. sec/min Angioedema,
AnaphylaxisAnaphylaxis
IV Cell mediated 48 hrs ContactIV Cell mediated 48 hrs Contact
dermatitis dermatitis
Allergens in LocalAllergens in Local
EstersEsters - usually to the Para-amino-benzoic- - usually to the Para-amino-benzoic-acid productacid product
Na bisulfite or metabisulfite Na bisulfite or metabisulfite - found in - found in anesthetics as perservative for anesthetics as perservative for vasoconstrictorsvasoconstrictors
MethylparabenMethylparaben - no longer used as - no longer used as perservative in dental cartridgesperservative in dental cartridges
Management of Allergy Pts.Management of Allergy Pts.
If the patient gives a history of allergy to local If the patient gives a history of allergy to local anesthetics - anesthetics - Assume that an allergy existsAssume that an allergy exists
Elective proceduresElective procedures
Postpone until work-up is completedPostpone until work-up is completed
Management of Allergy Pts.Management of Allergy Pts.
Emergency treatmentEmergency treatment
Protocol #1 - no invasive treatment ( I&D, Protocol #1 - no invasive treatment ( I&D, analgesics, antibiotics)analgesics, antibiotics)
Protocol #2 - use general anesthesiaProtocol #2 - use general anesthesia
Protocol #3 - Histamine blocker (Benadryl)Protocol #3 - Histamine blocker (Benadryl)
Protocol #4 - Others: electronic dental Protocol #4 - Others: electronic dental anesthesia, hypnosis, adjunctive N2Oanesthesia, hypnosis, adjunctive N2O
Allergy - signs/symptomsAllergy - signs/symptoms
Dermatologic:Dermatologic:
Urticaria - wheals, pruritisUrticaria - wheals, pruritis
AngioedemaAngioedema
Minor rashMinor rash
Allergy - signs/symptomsAllergy - signs/symptoms
Respiratory:Respiratory:
Laryngeal edemaLaryngeal edema
BronchospasmBronchospasm
distress dyspneadistress dyspnea
anxiety cyanosis or flushinganxiety cyanosis or flushing
wheezing tachycardiawheezing tachycardia
diaphoresis use of accessorydiaphoresis use of accessory
muscles muscles
AnaphylaxisAnaphylaxis
Typical progression Typical progression **
Skin reactionsSkin reactions
Smooth muscle spasms (GI, GU, respiratory)Smooth muscle spasms (GI, GU, respiratory)
Respiratory distressRespiratory distress
Cardiovascular collapseCardiovascular collapse
*may occur rapidly, with considerable overlap*may occur rapidly, with considerable overlap
Management of ReactionsManagement of Reactions
Delayed skin reactionDelayed skin reaction
Benadryl - 50 mg stat & Q6H X 3-4 daysBenadryl - 50 mg stat & Q6H X 3-4 days
Immediate skin reactionImmediate skin reaction
Epinephrine 0.3 mg IM or SCEpinephrine 0.3 mg IM or SC
Benadryl - 50 mg IMBenadryl - 50 mg IM
Observation, medical consultationObservation, medical consultation
Benadryl - 50 mg Q6H X 3-4 daysBenadryl - 50 mg Q6H X 3-4 days
Management of ReactionsManagement of Reactions
Bronchial constrictionBronchial constriction
Semi-erect position, O2 - 6 L/minSemi-erect position, O2 - 6 L/min
Inhaler or Epinephrine 0.3 mg IM or SCInhaler or Epinephrine 0.3 mg IM or SC
Benadryl - 50 mg IMBenadryl - 50 mg IM
Observation, medical consultationObservation, medical consultation
Benadryl - 50 mg Q6H X 3-4 daysBenadryl - 50 mg Q6H X 3-4 days
Mangement of ReactionsMangement of Reactions
Laryngeal edemaLaryngeal edema
Place supine, O2 - 6 L/minPlace supine, O2 - 6 L/min
Epinephrine 0.3 mg IM or SCEpinephrine 0.3 mg IM or SC
Maintain airwayMaintain airway
Benadryl - 50 mg IV or IMBenadryl - 50 mg IV or IM
Hydrocortisone - 100 mg IV or IMHydrocortisone - 100 mg IV or IM
Perform CricothyrotomyPerform Cricothyrotomy
Management of ReactionsManagement of Reactions
AnaphylaxisAnaphylaxis
Place supine, on flat surfacePlace supine, on flat surface
ABCs of CPR, ABCs of CPR, call for medical helpcall for medical help
Epinephrine 0.3 mg IV or IM (Q 5 mins)Epinephrine 0.3 mg IV or IM (Q 5 mins)
O2 - 6 L/min, monitor vital signsO2 - 6 L/min, monitor vital signs
After clinical improvement,After clinical improvement,
Benadryl and HydrocortisoneBenadryl and Hydrocortisone
Differential DiagnosisDifferential Diagnosis
Pyschogenic reaction (Syncope)Pyschogenic reaction (Syncope)
Overdose reactionOverdose reaction
HypoglycemiaHypoglycemia
Stroke (CVA)Stroke (CVA)
Acute adrenal insufficiencyAcute adrenal insufficiency
Cardiac arrestCardiac arrest
PREVENTIONPREVENTIONofof
SYSTEMIC COMPLICATIONSSYSTEMIC COMPLICATIONS
Prior to TreatmentPrior to Treatment
Complete review of medical statusComplete review of medical status
(including vital signs)(including vital signs)
Anxiety / Fear should be assessed and Anxiety / Fear should be assessed and managed before administering anestheticmanaged before administering anesthetic
Administration of AnestheticAdministration of Anesthetic
Place pt. supine or semi-supine positionPlace pt. supine or semi-supine position
Dry site, apply topical X 1 minDry site, apply topical X 1 min
Select appropriate drug for treatment (time)Select appropriate drug for treatment (time)
Vasoconstrictor unless contraindicated Vasoconstrictor unless contraindicated
Administration (cont.)Administration (cont.)
Weakest anesthetic in the minimum volumeWeakest anesthetic in the minimum volume
(compatible with successful anesthesia)(compatible with successful anesthesia)
Inject slowly (minimum of 60 sec / 1.8 ml)Inject slowly (minimum of 60 sec / 1.8 ml)
Continually observe -Continually observe -
Never leave patient alone after injectionNever leave patient alone after injection
Administration (cont.)Administration (cont.)
Use only aspirating syringeUse only aspirating syringe
Aspirate in two planes, before injectingAspirate in two planes, before injecting
Use sharp, disposable needles of adequate Use sharp, disposable needles of adequate diameter and lengthdiameter and length