PLACENTAL BLOOD FLOW DURING CAESAREAN SECTION PERFORMED UNDER SUBARACHNOID BLOCKADE

Subarachnoid blockade using 0.5% bupivacine after a "preload"of Ringer's lactate solution 1500–2000 ml i.v. was studiedin nine patients undergoing elective Caesarean section. Ephedrineinfusion 50 mg in 500 ml was instituted at the first signs ofmaternal hypotension in seven patients. Although significantdecreases in mean maternal systolic, mean and diastolic arterialpressures were recorded, the individual decreases in pressurewere less than 30 mm Hg in all except two patients. In generalplacental blood flow did not change, although there was a markedincrease in one patient with toxaemia and a decrease in onewoman with diabetes mellitus. The babies were unaffected atdelivery. Preventive measures, especially the "preload" infusion,are important in the maintenance of adequate placental perfusionin patients undergoing Caesarean section under subarachnoidblockade.