Ether

AGA UMAR TARIQ
MSC OTT/ANAESTHESIA

1. Ether Umar tariq

2. ETHER Ether is still used in certain specific situations and in certain parts of world. First public demonstration of ether was given by W.T.G. Morton on 16 october 1846 for the removal of jaw tumour.

3. Physical properties It is pungent smelling liquid , decomposes in presence of light, air and heat so stored in amber colored bottles which are wrapped in black paper, Highly inflammable and explosive. Highly irritant vapour

4. Anaesthetic properties Induction is very slow(BG coefficient 12.0) and very unpleasent (pungent smelling) , so there are high chances of laryngospasm with ether induction Potency is moderate (MAC 1.92) Very good analgesic Usually required concentration is 5-15 %. Very good muscle relaxant

5. Delivery method Open drop method EMO inhaler Copper kettle vaporizer Oxford miniature vaporizers

6. Systemic effects CVS: it does not depress myocardium rather it stimulates sympathetic system causing tachycardia and hypertension It does not depress respiration It is potent bronchodilator. Only inhalational agent which preserves ciliary activity Tracheobronchial secretions are markedly increased ,so premedication with atropine/ glycopyrolate is necessary

7. Highest incidence of nausea and vomiting among inhalational agents. ICT is increased with ether. It readily crosses placenta It releases catacholamines and can cause hyperglycemia so should not be used in diabetics

8. Advantages It is very cheap Can be used as a sole agent for anaesthesia as it has three basic properties narcosis , analgesia , muscle relaxation or in other words it is the only complete anaesthetic agent. Very safe ; does not produce any cardiac or respiratory depression, so can be used in remote places( like wars and disasters) and with less experienced hands

9. Requires very less instrumentation for delivery. Does not produce any toxic metabolite.

10. Disadvantages Highly inflammable and highly explosive. There have been death reports following burns by ether. Induction is very irritating and unpleasent and can induce severe laryngospasm Tracheobronchial secretions are increased Recovery is delayed Very high incidence of nausea and vomiting

11. Enflurane Has been recently obsoleted from anaesthesia practice

12. Physical properties Colourless Etheral odor Non inflammable at clinical concentration but inflammable at higher concentration(above 5%)

13. Anaesthesia properties Moderate potency, moderate induction , and recovery time Not a good analgesic Muscle relaxation is moderate MAC is 1.68

14. Systemic effect Decreases BP ,causes bradycardia and decreases cardaic output Caused marked respiratory depression Increases ICT Depresses hepatic function due to decreased hepatic blood flow