the effect comparison of two injections doses of magnesium sulfate on hemodynamic changes caused by laryngoscopy and endotracheal intubation in caesarean patients with general anesthesia

background: the aim of this study was to evaluate the effect of two injections doses of magnesium sulfate for controlling and reducing hemodynamic changes caused by laryngoscopy and endotracheal intubation in pregnant women who were candidates for caesarean section with general anesthesia. methods: in this controlled randomized double-blind clinical trial, 165 pregnant women who were candidates for caesarean section were allocated into three groups of receiving 40mg/kg of magnesium sulfate (m1 group), 60 mg/kg of magnesium sulfate (m2 group) and placebo (p group) before induction of anesthesia. systolic blood pressure (sbp), diastolic blood pressure (dbp), mean of arterial pressure (map), heart rate (hr) and arterial oxygen saturation (spo2) were measured and recorded at the baseline (before the induction), right before the intubation and 1, 3, 5 and 10 minutes after laryngoscopy and endotracheal intubation. the apgar score of the neonates was also measured and recorded 1 and 5 minutes after delivery. results: the mean of changes in systolic blood pressure and mean of arterial pressure showed a significant difference between the m1 and m2 groups with the placebo group right before the intubation and 1, 3 and 10 minutes after laryngoscopy. the mean of changes in heart rate was specifically significant 1, 5 and 10 minutes after intubation in the m2 group (p< 0.05). the apgar score of neonates had no significant difference 1 and 5 minutes after delivery (p> 0.05). conclusion: for inducing anesthesia in pregnant women, using 60 mg/kg of magnesium sulfate decreased the hemodynamic changes after laryngoscopy and endotracheal intubation and it had no adverse effect on the apgar score of the neonates.