Trilene anesthesia is a non-flammable, good analgesic-and cheap agent.
Physical properties of trilene anesthesia : It has bp 80°C, VP 60 mm Hg, oil/gas coefficient 600 and blood/gas 12, metabolism 40%, unstable, preservative 1:10,000 thymol as stabilizer and coloured with waxoline blue 1 in 200,000, MAC 0.17%.
Trilene anesthesia reacts with sodalime to produce phosgene which is neurotoxic. In light planes it is a good analgesic and was used in inhalational labour analgesia. Deep anaesthesia may resuit in tachypnoea due to accentuation of Herring-Breuer reflex and is arrhythmogenic. It is metabolized to chloral hydrate and in presence of soda lime to phosgene and carbon monoxide.
In a difficult situation trilene anesthesia can be used in a draw-over vapourizer. It can be used in semiclosed circuit on the Boyle’s machine bottle or Tritec vaporizer. The bottle has a lock for the closed circuit. It was extensively used in UK as an obstetric analgesic in the I 950s and I 960s. It was used in India till very recently.
Miller’s Anesthesia says the following about trilene anesthesia –
One attempt to produce a nonflammable alternative to ether and cyclopropane was made in 1935, when trichloroethylene or trilene anesthesia was introduced.
It was promoted by Christopher L. Hewer (1896-1986) as a nonexplosive agent, but it was eventually withdrawn when it was shown to decompose to the toxic nerve poison dechloroacetylene in the presence of soda lime and to produce phosgene, a severe respiratory irritant, when electrocautery was used.
Historically speaking, an uncommon anesthetic, trichloroethylene or trilene anesthesia, reacts with soda lime to produce toxic compounds.
In the presence of alkali and heat, trichloroethylene degrades into the cerebral neurotoxin dichloroacetylene, which can cause cranial nerve lesions and encephalitis. Phosgene, a potent pulmonary irritant, is also produced and can cause adult respiratory distress syndrome.