Comparison of phenylephrine requirements to treat post-spinal hypotension in early onset and late onset preeclampsia patients undergoing caesarean section – An analytical experimental study

Spinal anaesthesia will be administered with hyperbaric 0.5% bupivacaine with 10 microg fentanyl. Hypotension after spinal anaesthesia will be defined as a fall of systolic blood pressure of 20% or more from baseline. Phenylephrine bolus of 50 microg will be administered to treat every hypotensive blood pressure value. Umbilical arterial and venous blood samples of the fetus will be obtained for blood gas analysis. After the procedure, on the basis of history from the patient/relatives and discussion with the obstetrician, the patient will be allocated to either early or late onset preeclampsia group. The total phenylephrine requirements, maternal haemodynamic variables, number of hypotensive episodes, incidence of reactive hypertension and bradycardia, neonatal Apgar scores, fetal acid-base status and maternal complications will be recorded.