general anaesthesia in obstetrics
The following ought to be considered in anaesthetising a woman in labour:
- normotension, because of aorto-caval compression, may not actually be normal, and may be harmful to the fetus
- the size of the lungs are reduced in a term mother, and the oxygen requirements are higher
- acid aspiration is a common complication with the high pressures of labour, especially when combined with agent which delay gastric emptying (eg opiates)
- direct effects of drugs on the fetus can be avoided with a quick delivery, ie no time for transplacental diffusion
- anaesthesia is always a risk in labour; an emergency anaesthetic constitutes a high risk.
- most of the mortality and morbidity results from failure to intubate with subsequent hypoxia and aspiration.
- the anaesthetic must remove awareness!
Last reviewed 01/2018