Hydroxyethylstarch compared with modified gelatin as volume preload before spinal anaesthesia for Caesarean section.

We studied 90 patients undergoing elective Caesarean section under spinal anaesthesia who received lactated Ringer's solution 1000 ml with up to 1000 ml of modified gelatin, lactated Ringer's solution 1000 ml with up to 1000 ml of 6% hydroxyethylstarch or only up to 1000 ml of 6% hydroxyethylstarch. Lumbar puncture was performed as soon as 500 ml of the colloid were infused. The incidence of hypotension, number of patients requiring a vasopressor and doses of ephedrine required to restore arterial pressure were significantly lower in favour of those receiving the crystalloid-hydroxyethylstarch combination. In both groups receiving the 2000 ml preload, packed cell volume (PCV) values decreased by more than 20%, which may be of concern in patients already presenting with mild anaemia. In patients who received the colloid without the crystalloid, PCV values decreased by 14% but the risk of severe hypotension was comparable with the crystalloid-gelatin combination.