[Spinal anaesthesia for Caesarean section: dose injection speed have an effect on the incidence of hypotension?].

Objective: To study effect of injection rate on spinal blockade and haemodynamic of spinal bupivacaine for Caesarean section.

Study Design: Prospective and randomized.

Patients And Methods: Sixty ASA I-II patients scheduled for elective Caesarean section were randomized to receive either fast (20 seconds, group R, n=30) or slow (60 seconds, group L, n=30) spinal injection of 10 mg of hyperbaric bupivacaine 0.5% associated with 25 microg of fentanyl and 100 microg of morphine. Sensory and motor blockade and haemodynamic parameters were recorded.

Results: Profiles of sensory and motor block were similar in both groups. Variations of arterial blood pressure and total dose of ephedrine were not different between R and L groups. However, the number of patient with systolic blood pressure lower than 100 mmHg were significantly lower in L group than in R group (p=0.04). Incidences of adverse effects were similar in both groups.

Conclusion: Result of the present study suggests that a slow rate of injection would induce lower incidence of hypotension induced by spinal bupivacaine for Caesarean section.