Chapter 36: Asphyxiants

gaseous poisons, which produce respiratory embarrassment, leading to asphyxia.

reduce the body’s ability to absorb, transport, or utilize inhaled oxygen.

These are inert gases and they deprive tissue of oxygen by their ability to displace oxygen.

are gases, which can damage the respiratory tract by destroying the integrity of mucosal barrier and produce non-cardiogenic pulmonary edema, which impairs the oxygen diffusion across the alveolar membrane.

gases, which produce significant systemic toxicity by specialized mechanisms.

________ is a colorless, tasteless, odorless and nonirritant gas, produced whenever there is incomplete combustion of carbon.

_______ has got 200 to 300 times more affinity for hemoglobin (Hb) than oxygen (O2) forming carboxyhemoglobin, which are quite stable

______ resulting from hem degradation constitutes another source of CO. It is an end product of normal metabolism and is formed during the conversion of heme into biliverdin.

This is a simple non-invasive technique of detecting oxygen saturation measured by discrete wavelengths of light corresponding to saturated and unsaturated hemoglobin (660 and 940 nm) by a photodetector.

This radiograph may reveal ground glass appearance, perihilar haze, parabronchial cuffing, and intra-alveolar edema.

Solid form of CO2

Chemicals that are used only in warfare.

• Chloracetophenon (CAP), Bromobenzyl cyanide (BBC), Ethyl iodoacetate (KSK)

• These war gases are harmless to life.

• Chlorine (Cl2 ), Phosgene (CO Cl2), Diphosgene

• These war gases can be fatal and kill the victim.

• Diphenyl chlorasine (DA), Diphenylamine chlorasine (DM), Diphenyl cyanarsine (DC)

• Vapors can result in intense pain and irritation in the nose and sinuses leading to sneezing, malaise, headache, and salivation followed by nausea, vomiting and chest pain.

• Chemical with acetylcholine-like action

  • They are compounds related to phosphate esters in action and toxicity. They are colorless and odorless volatile liquids.

Carbon monoxide (CO), Hydrocyanic acid (HCN), Hydrogen sulfide (H2S).

• Mustard gas, Lewisite.

• It can also develop severe irritation of the skin especially over the oily areas, such as the face, axillae, pubis, scrotum, etc., especially over the moist areas.

• There can be inflammation of the stomach leading to nausea, vomiting, pain abdomen, diarrhea, etc.

It can be considered under several classifications, namely: agrochemicals, war gases, irritants and miscellaneous poisons.

Liquid form of Cyanide

These are protoplasmic cytotoxic poisons. They act by inhibiting cytochrome oxidases for utilizing O2 in a cell, leading to internal asphyxia (cellular asphyxia), leading to death. It can also act on other enzymes mildly. It also acts as a corrosive on the mucosa.

At room temperature, _____ is a highly water-soluble, colorless, irritant gas with a unique pungent odor.