Anaesthetic death and Idiosyncras

y

Presented by:Dr. Debarshee chakraborty

PGT, Department Of Forensic Medicine and

ToxicologyGauhati Medical

Collge and Hospital

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Anesthetics

General anesthetics

Inhalational agents:Gas: nitrous oxideLiquids: ether, halothane, enflurane, isoflurane, sevoflurane

Intravenous agents:Inducing agents: Thiopentine sodium, profol, etomidateSlower acting drugs:benzodiazepines, ketamine, fentanyl

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Local anesthetics

Injectable:Low potency, short duration :procaine , chloro-procaineIntermediate potency and duration:Lidocaine ,prilocaineHigh potency, long duration:tetracaine, bupivacaine, ropivacaine

Surface acting:

Soluble: cocaine, lidocaine Insoluble: benzocaine.

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Skeletal muscle relaxants :

Peripherally acting:

A. Neuromuscular blocking agents:1.non- depolarizing blockers :a.Long acting- d-tubocurarine,

gallamineb. Intermediate acting :vecuronium, atracuriumc. Short acting :mivacurium2.Depolarizing blockers : succinylcholine, decamethonium

B. Directly acting agents : dantrolene sodium

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Centrally acting :

Mephensin group: mephensin , chlorzoxazoneBenzodiazepinesGABA derivatives: baclofen

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Type of anesthe

sia

Nature of

operation

Condition of the

patient

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CATEGORIES

Let us classify

Anesthetic death

Post anesthetic death

During anesthesia

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Deaths during anesthesia : etiology:

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• Respiratory failure/ respiratory depression

• Airway obstruction

• Pneumothorax

• Aspiration of gastric contents

• Hypovolemia

• Cardiac arrythmia

• Equipment failure

• Overdose

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• ANAESTHETIC MISADVENTURES

• Inexperience

• Monitoring and vigilance failure

• Malignant hyperthermia

• Drug induced reactions to anesthetics

• Adverse drug reactions

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COMPLICATIONS OF GENERAL ANAESTHESIA• Pain• Nausea and vomiting -

up to 30% of patients• Damage to teeth - 1 in

4,500 cases• Sore throat and

laryngeal damage• Anaphylaxis to

anesthetic agents - figures such as 0.2% have been quoted

• Cardiovascular collapse• Respiratory depression• Aspiration pneumonitis -

up to 4.5% frequency has been reported; higher in children

• Hypothermia

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• Hypoxic brain damage• Nerve injury - 0.4% in

general anesthesia and 0.1% in regional anesthesia

• Awareness during anesthesia - up to 0.2% of patients; higher in obstetrics and cardiac patients

• Embolism - air, thrombus, venous or arterial

• Backache• Headache

• Idiosyncratic reactions related to specific agents,

• Iatrogenic, example: pneumothorax related to central line insertion

• Death

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COMPLICATIONS OF REGIONAL ANAESTHESIA

• Pain - 25% of patients still experience pain despite spinal anesthesia

• Post-dural headache from CSF leak

• Hypotension and bradycardia through blockade of the sympathetic nervous system

• Limb damage from sensory and motor block

• Epidural or intrathecal bleed

• Respiratory failure if block is 'too high'

• Direct nerve damage

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• Hypothermia• Damage to

the spinal cord - may be transient or permanent

• Spinal infection

• Aseptic meningitis

• Haematoma of the spinal cord - enhanced by use of LMWH preoperatively

• Anaphylaxis• Urinary

retention• Spinal cord

infarction

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COMPLICATIONS OF LOCAL ANAESTHESIA

• Pain• Bleeding and

haematoma formation

• Nerve injury due to direct injury

• Infection• Ischaemic

necrosis

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ASA CLASSIFFICATION

• ASA risk I-normally healthy individual

• ASA risk II-mild systemic disease• ASA risk III-severe not

incapacitating• ASA risk IV-incapacitating constant

threat to life• ASA risk V-morbid and not expected

to survive 24 hours with or without operation

• E= emergency

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MORTALITY

Mortality according to ASA

ASA I- 0.1% ASA II- 0.2% ASA III- 1.8% ASA IV- 7.8% ASA V- 9.4 % ASA does not consider age, smoking, obesity, pregnancy, CAD, difficult intubation, inherent risk of operation

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CAUSATIVE FACTORS• Physiologic-hypoxia

• Pharmacologic- allergy

• Physical-heat• Malfunction or

misuse of apparatus

• Human error-• technical•

judgmental• monitoring

and vigilance failure

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ANAESTHETIC MISADVENTURES

Is a human error or equipment

failure that could have led(if not discovered or corrected in

time), or did lead to an undesirable outcome, ranging

from increased length of hospital

stay to death”

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PREVENTION• Training and

supervision• Specific protocol

development, more complete preoperative assessment and equipment and apparatus inspection

• Additional monitoring of instrumentation and equipment and human factors improvements

• Organizational improvements

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AUTOPSY PROCEDUREFull clinical information -history -conditions requiring surgery -other pre-existing condition -pre-anesthetic medications -anesthetic deaths -burn or explosion -shock and haemorrhage -blood transfusion -resuscitative measures -equipment

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TOXICOLOGICAL EXAMINATION

• Both the lungs• 2 gram of fat

from mesentery• 10 grams of

skeletal muscle• 100 gram of

brain • 100 gram of

liver• 100 gram of

kidney

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• Alveolar air should be collected with a needle and syringe under water by pulmonary puncture before chest is opened.• Exudates for

bacteriological examination.• Blood for serology• Blood for culture

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MEDICOLEGAL PROBLEMS

• Proper physician- patient relationship

• Establishment of identity

• Informed consent-separate for surgery and anaesthesia

• Documentation• Acquainted with

new technology and instruments

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LEGAL QUESTIONS

• Informed consent

• Was the operation or anesthesia necessary in the circumstances

• Pre-operative evaluation

• Suitably prepared

• Test dose given

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• Suitable type of anesthesia used

• Performed with reasonable skill and care

• Arrangements for any emergency

• In emergency suitable steps taken to resuscitate

• Arrangements for recovery of patient

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Idiosyncrasy

Idiosyncrasy is defined as an individual’s unique

abnormal reaction to a particular drug, It may be

genetically determined. It has no relation to the

pharmacology, amount or concentration of the drug.

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DiseaseIdiosyncrasy defined the way physicians conceived diseases in the 19th century. They considered each disease as a unique condition, related to each patient. This understanding began to change in the 1870s, when discoveries made by researchers in Europe permitted the advent of a 'scientific medicine', a precursor to the Evidence-Based Medicine that is the standard of practice today.

PharmacologyIn contemporary medicine (as of 2007), the term idiosyncratic drug reaction denotes a non-immunological hypersensitivity to a substance, without connection to pharmacological toxicity. Idiosyncratic stresses here the fact that other individuals would react differently, or not at all, and that the reaction is an individual one based on a specific condition of the one who suffers it.

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An idiosyncrasy causing symptoms like an allergy is also called pseudoanaphylaxis.Psychiatry and psychology

In psychiatry, the term means a specific and unique mental condition of a patient, often accompanied by neologisms. In psychoanalysis and behaviorism, it is used for the personal way a given individual reacts, perceives and experiences a common situation: a certain dish made of meat may cause nostalgic memories in one person and disgust in another. These reactions are called idiosyncratic.

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In drug idiosyncrasy, a person’s individual genetic makeup causes an unusual reaction to the drug, often because of a lack of a particular enzyme, which is important in dealing with that drug in the body. One example is “cholinesterase deficiency”, a condition where the effects of anesthetic agent, suxamethonium, are prolonged well beyond the usual few minutes, because the individual lacks the enzyme that normally limits its effects to a short time. The patient’s muscles are paralysed for longer than normal so assistance with breathing must be given for much longer than usual.

pathophysiology

Omg anything is possible ????????

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Idiosyncrasy has been

defined as a

genetically

determined

abnormal response to a drug.

Not all idiosyncra

tic reactions

have a pharmacogenetic cause.

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Eye Catching Points

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not dose-related

Non -allergic

Eye Catching Points

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unknown

Enzymopathy

Psychogenic

Congenitall Acquired

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Types of idiosyncrasy

Drug toxicity due to

deficient metabolism

Increased sensitivity to drug effect

Novel drug effect

Decreased responsiveness to drug

Abnormal distribution of material

Based on Hypothetic etiologies

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Clinically

• Pallor • Tachycardia• Hypotensio

n• Decreased

heart rate• Collapse

Majority

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Some examples of Idiosyncrasy

A single dose of triflupromazine induces muscular dystonia in some individuals specially children

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Only few doses of carbamazepine may cause ataxia in some people.

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One tablet of chloroquine may cause vomiting and abdominal pain

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Nitrites and other drugs causing methemoglobinemia (due to oxidizing effects) - basis is abnormal hemoglobins (M and H)

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Aminoglycoside antibiotic-induced deafness* - basis unknown; apparent transmission by females

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Chloramphenicol-induced bone marrow depression*- basis unknown

Drugs and Chemicals Unequivocally

Demonstrated to Precipitate Hemolytic

Anemia in Subjects with G6PD

Deficiency

Acetanilide Nitrofurantoin PrimaquineMethylene Blue Sulfacetamide NalidixicAcidNaphthalene SulfanilamideSulfapyridine Sulfamethoxazole

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Porphyrias are associated with overproduction of porphyrins: acute abdominal pain, psychosis, “purple pee”.Acute intermittent porphyria the exacerbation is induced by barbiturates, sulfonamides, and griseofulvin

Acute Intermittent Porphyria

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malignant hyperpyrexia with suxamethonium, succinylcholine-related apnoea

Some examples of anesthetics causing Idiosyncrasy

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Prevention

1.Do not use that drug preferably , which the patient gives you a history of previous reaction to it.

2.Inject slowly and observe the patient closely .

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