RAPID ADMINISTRATION OF CRYSTALLOID PRELOAD DOES NOT DECREASE THE INCIDENCE OF HYPOTENSION AFTER SPINAL ANAESTHESIA FOR ELECTIVE CAESAREAN SECTION

Twenty parturients undergoing elective Caesarean section wereallocated randomly to receive crystalloid preload 20 ml kg^–1over either 20 min or 10 min before spinal anaesthesia. Significanthypotension (systolic arterial pressure <100mm Hg and <80% of baseline value) occurred in six of the 10 patients inthe 20-min preload group and seven of 10 patients in the 10-minpreload group (ns). Both groups had a significant (P < 0.05)increase in central venous pressure during the preload period.The mean central venous pressure in the 10-min group was 11.9mm Hg (range 6–19 mm Hg), which was significantly greater(P < 0.05) than that in the 20-min group (mean 7.3 mm Hg,range 2–13 mm Hg). Three patients in the 10-min grouphad clinically unacceptable increases in central venous pressure.This study has demonstrated that rapid administration of crystalloidpreload before spinal anaesthesia did not decrease the incidenceor severity of hypotension, and questions the role of crystalloidpreload.