Lateral table tilt for Caesarean section

Abstract

The deleterious effects on maternal haemodynamics of inferior vena-caval compression by the gravid uterus are well e~tablished.'-~The resultant decrease in cardiac output may constitute a threat to both mother' and f ~e t u s .~-~ These problems may be alleviated by lateral displacement of the uterus,'", by tilting the patient with a wedge," or by operating in the left lateral position.'3Lateral table tilt may be advantageous for Caesarean section using spinal analgesia, but results appear less conclusive under general anaesthesia.' MethodA hundred mothers scheduled for elective Caesarean section under general anaesthesia have been studied.Fifty patients were managed in the supine posture with no tilt; the rest were tilted, either to the left or the right side by adjustment of the operating table.A standard technique of anaesthesia was used, and the induction to delivery interval was limited to less than 12 minutes whcre possible.The patients studied were in the lower socio-economic group, but otherwise conformed to the 'clinically acceptable ideal case'.I5 Placental function was believed to be normal, and there was no evidence of pre-cclamptic toxaeniia, renal disease, hypertension, diabetes, antepartum haeniorrhage, or rhesus incompatibility with antibodies.Gestational age was between 36 and 42 weeks; cases of multiple pregnancy were excluded.Patients were not in labour and membranes were intact.Mothers were divided at randoin into two groups of fifty (group 1 and group 2).Group I received no special attention prior to entering theatre, and were operated on in thc supine position.Disturbing drops in blood pressure, or changes in heart rate, were managed by left lateral displacement of the uterus pcrforrned by the surgical assistant.