The document discusses different types of asphyxiants including irritants, chemical asphyxiants, simple asphyxiants, and volatile drugs. Irritants such as smoke and tear gas injure the air passages while chemical asphyxiants like carbon monoxide and hydrogen sulfide prevent oxygen utilization. Simple asphyxiants like carbon dioxide act by excluding oxygen. Volatile drugs can act as anesthetics or toxins to organs. Specific asphyxiants are then discussed in more detail including their properties, mechanisms of action, signs and symptoms, and treatment approaches.
2. .
Classification
Chemical Simple Volatile
Irritants Systemic
asphyxiants asphyxiants Drugs.
Dr Hemanth S Naik, BMCRI
3. IRRITANTS
Injure the air passage
1. Smoke
2. Teargas
3. Phosgene
4. Ammonia
5. Chlorine
6. Nitrogen di oxide, etc.
Dr Hemanth S Naik, BMCRI
4. CHEMICAL ASPHYXIANTS
Combine with hemoglobin or act on tissue
Preventing oxygen utilization
1. Carbon monoxide
2. Hydrogen sulphide
3. Cyanide, etc.
Dr Hemanth S Naik, BMCRI
5. SIMPLE ASPHYXIANTS
Inert gases in high concentration act
mechanically by excluding oxygen
1. Carbon di oxide
2. Methane
3. Helium, etc.
Dr Hemanth S Naik, BMCRI
6. VOLATILE DRUGS
Act as anesthetic or toxic agents to liver,
kidney and other organs
Hydrocarbons
SYSTEMIC POISONS
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8. Properties
Colorless, tasteless, Non-irritating gas
Produced due to incomplete combustion of
carbon
Lighter than air
Burns with blue flame
Dr Hemanth S Naik, BMCRI
12. Action
Carbon monoxide binds to hemoglobin
(reducing oxygen transportation),
myoglobin (decreasing its oxygen storage
capacity)
And mitochondrial cytochrome oxidase
(inhibiting cellular respiration).
Dr Hemanth S Naik, BMCRI
13. Elimination
Major part by lung
Half life with
1. 21% oxygen=4 – 5 hours
2. 100% oxygen=80 – 90 min
3. Hyperbaric oxygen=30 min
Dr Hemanth S Naik, BMCRI
18. Treatment
First aid is to immediately remove the victim
from the exposure
Begin CPR if needed.
100% oxygen by a tight fitting oxygen mask.
Hyperbaric oxygen
Electrolyte balance
Dr Hemanth S Naik, BMCRI
19. Postmortem changes
External
1. Cherry red color of skin
2. Cutaneous bullae
Internal
1. Cherry red color of blood n tissues
2. Pulmonary n cerebral edema
3. Necrosis n cavitation of basal ganglia, globus
pallidus
Dr Hemanth S Naik, BMCRI
22. .
Definition: Any chemical (gaseous, liquid, solid)
used to produce destruction or damage mostly at
the time of war
Classification
Vesicants or Blistering Gases
Asphyxiants or Lung irritants
Lachrymators or Tear gas
Nasal irritants
Paralysants n Nerve gases
Dr Hemanth S Naik, BMCRI
23. Vesicants
Causes irritation of skin, nose, throat and
respiratory passage
Nausea, vomiting and abdominal pain
1. Mustard gas
2. Sulphur
3. Phosgene
4. Volatile liquids
Dr Hemanth S Naik, BMCRI
24. Mustard gas
Most effective gas of the First World War
Introduced by Germany in July 1917
One nurse, Vera Brittain, wrote: "I wish those people
who talk about going on with this war whatever it
costs could see the soldiers suffering from mustard
gas poisoning. Great mustard-coloured blisters,
blind eyes, all sticky and stuck together, always
fighting for breath, with voices a mere whisper,
saying that their throats are closing and they know
they will choke."
Dr Hemanth S Naik, BMCRI
27. Tear Gas
During the first World War, the French were
the first to employ gas, using 26 mm grenades
filled with tear gas (ethyl bromoacetate) in
August, 1914
Mainly Chloracetophenone (C.A.P),
Ethyliodoacetate (K.S.K), Bromobenzylcynaide
(B.B.C) are used
Dr Hemanth S Naik, BMCRI
29. Nasal irritants
Mainly used to control riots
Ortho-chlorobenzylidene malanonitrate (CS)
used by Law Enforcement Agencies and Military
for self protection
Dr Hemanth S Naik, BMCRI
30. Nerve Gases
Esters of Phosphoric acid n are identical in
their biological activity to organophosphates
Colorless and odorless volatile liquids
Inhibit acetylcholine esterase
1. Tabun (GA)
2. Sarin (GB)
3. Soman (GD)
Dr Hemanth S Naik, BMCRI
32. Methyl isocynate (MIC)
Stable liquid below 27c, gaseous at 31c
Highly volatile n inflammable
Used in manufacture of pesticides, adhesives n
plastic
Sings n symptoms include irritation of skin,
mucous membrane and systemic effects
Dr Hemanth S Naik, BMCRI
34. Bhopal Gas Tragedy
The Bhopal disaster was an industrial disaster
that occurred in the city of Bhopal, Madhya
Pradesh, India, resulting in the immediate deaths
of more than 3,000 people
The incident took place in the early hours of the
morning of December 3, 1984
A Union Carbide subsidiary pesticide plant
released 40 tones of methyl isocyanate (MIC) gas
Dr Hemanth S Naik, BMCRI
39. . Heavy colorless gas with a faintly sweet odour
Act as simple asphyxiant by preventing the
tissue from obtaining oxygen
Symptoms include labored breathing and mental
confusion (> 5% concentration in air)
Dyspnoea, ringing in ears, loss of muscle power,
unconsciousness, coma and death (60-80%
concentration)
Treatment: Oxygen, artificial respiration and
symptomatic
Dr Hemanth S Naik, BMCRI
43. Properties
vegetable acid (distributed in many fruits n
leaves) in the form of harmless glucoside
amygdalin
colorless gas or pale blue, highly volatile liquid
has a faint, bitter almond-like odor
Dr Hemanth S Naik, BMCRI
44. Other names
1. Hydrocyanic acid
2. Prussic acid
3. Formonitrile
4. Formic anammonide
5. Carbon hydride nitride
6. Cyanane
7. Cyclon
Dr Hemanth S Naik, BMCRI
46. Source
Cherries, apricots, apples, bitter almonds
Some millipedes , burnet moths release
hydrogen cyanide as a defense mechanism
contained in the exhaust of vehicles, in tobacco
and wood smoke
100 g of crushed apple seeds can yield 219 mg
of Amygdalin which can generate ~10 mg of
HCN
Dr Hemanth S Naik, BMCRI
49. Application
Tempering steel
Dyeing
Explosives
Engraving
Acrylic resin plastic
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50. Action
Inhibits the action of cytochrom oxidase,
carbonic anhydrase (Oxygen utilization
hindered)
Interfere with intracellular oxidative process in
the tissues
Histotoxic anoxia
Dr Hemanth S Naik, BMCRI
51. Absorption n Excretion
Cyanide Stomach
(Inhaled, Ingested) (HCL, gastric juice)
Hydrocyanic acid
and chlorine
Dr Hemanth S Naik, BMCRI
52. Signs n symptoms
Burning taste, feeling of constriction in the
throat .
Excessive salivation and blood stained froth
Headache, vertigo and giddiness
Hurried breath n increased blood pressure with
decreased heart rate
Smell of bitter almond
Dr Hemanth S Naik, BMCRI
54. Signs n symptoms
Convulsions n unconsciousness
Opisthotonus, trismus
Skin is covered with sweat and is brick red in
color
Eyes are glassy and prominent, pupils dilated
and non reactive to light
Dr Hemanth S Naik, BMCRI
56. Treatment
Principle
Methemoglobin
Haemoglobin
By giving nitrates
Thiocyanate Cyanmethemoglobin
Excreted in urine Non toxic
Dr Hemanth S Naik, BMCRI
58. Treatment
Break 0.2 ml ampoule of AMYL NITRITE in a
hand kerchief and hold over the patients nose
for 15 – 30 sec every min
SODIM NITRITE infusion
SODIUM THIOSULPHATE infusion
VIT B12 4 mg iv infusion
EDTA chelating agent
Dr Hemanth S Naik, BMCRI
59. Postmortem changes
Postmortem staining cherry red in color
Bitter almond odor
Edema of lungs
Stomach mucosa red and congested
Dr Hemanth S Naik, BMCRI
62. Properties
Colorless gas.
Odor similar to rotten eggs
Produced in nature primarily through the
decomposition of organic matter by bacteria.
Sewer gas contains hydrogen sulphide
Dr Hemanth S Naik, BMCRI
63. Sewer Gas (carbon dioxide, methane, hydrogen sulphide)
5
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64. Action
Inhibition of cytochrome oxidase
Binds to hemoglobin in red blood cells
interfering with oxygen transport.
Exposure to hydrogen sulfide occurs primarily by
inhalation but can also occur by ingestion (contaminated
food) and skin (water and air).
Dr Hemanth S Naik, BMCRI
66. Signs n symptoms
Beginning of Eye Irritation
Slight conjunctivitis and respiratory tract
irritation
Loss of consciousness
Cessation of respiration, and death
Dr Hemanth S Naik, BMCRI
67. Treatment
Move the patient to fresh air immediately
100% oxygen
Amyl nitrite inhalation
Sodium nitrite infusion
Dr Hemanth S Naik, BMCRI
68. Postmortem changes
Rotten egg odour
General signs of asphyxia
Greenish purple discoloration of blood and
viscera
Dr Hemanth S Naik, BMCRI