The effect of intraoperative magnesium sulphate infusion on the course of neuromuscular blockade of atracurium

Abstract EN

Background : Magnesium sulphate (MgSO4) infusion has been increasingly used during anaesthesia and in intensive care units.

The main problem that may arise with the use of MgSO4 , is its interaction with non-depolarizing muscle relaxants.

Aim of the work : the current work was designated to study the effect of Mg2+ on neuromuscular blockade by atracurium during the operative period.

Patients and methods : this study was carried out on forty patients scheduled for major abdominal surgery at NCI.

All patients had the same premedication and general anaesthesia.

Induction of anaesthesia was done with pro-pofol and atracurium to facilitate tracheal intubation, and maintenance was carried on by isoflurane 0.5 % and 60 % nitrous oxide in oxygen.

Patients were, then, randomly divided into two groups, 20 patients (group I) were observed as a control group, while patients of group II (20) had a bolus dose of MgSO4 (3gm) after induction of anaesthesia.

This was followed by a continous infusion of 0.5 gm.h-1 all through the operative period.

Comparison between groups was done as regards the intubating conditions, haemodynamic stability, the effect of MgSO4 on the course of atracurium neuromuscular blockade (time of onset, clinical duration and recovery index).

Side effects after reversal with neostigmine and atropine, and the observed reversal time were demonstrated.

Results : patients at MgSO4 group had better intubat-ing conditions and haemodynamic stability.

MgSO4 potentiated the action of atracurium induced neuromuscular blockade, with significant increase in the time of onset, clinical duration and reversal time after neostigmine.

Conclusion : MgSO4 infusion has many advantageous effects during the course of anaesthesia.

However, adequate neuromuscular blockade monitoring is mandatory.