Anaesthesia and the sick foetus

The primary cause of foetal illness is placental pathology. The use of diagnostic ultrasound allows for a better understanding of how the foetus may be compromised by inadequate placental function. Anaesthesia affects placental function by changing uteroplacental and umbilical placental perfusion. Regional anaesthesia may have a beneficial effect on these circulations although general anaesthesia may be adapted to produce minimal disturbance of placental circulatory dynamics. The advantages and disadvantages of particular anaesthetic techniques in the delivery of the sick foetus are discussed.