The use of esmolol and magnesium to prevent haemodynamic responses to extubation after coronary artery grafting

Abstract

Background and objective: The haemodynamic responses during extubation can cause complications after open-heart surgery. In this study, we aimed to examine the effect of esmolol and magnesium before extubation on these haemodynamic responses.

Methods: Following the approval of local Ethics Committee, 120 patients having coronary artery bypass grafting with extubation in the intensive care unit were included in the study. Patients were allocated to receive esmolol 1 mg kg-1 (group I, n = 40), magnesium 30 mg kg-1 (Group II, n = 40) or normal saline (Group III, n = 40). Study medication was administered as a 20-min infusion in a volume of 20 mL. Patients were extubated just after termination of the infusion. Heart rate, blood pressure and central venous pressure were recorded prior to drug administration, before extubation, during extubation and 1 min after extubation.

Results: Heart rate was lower in Group I than in Groups II (P < 0.05) and III (P < 0.001) and lower in Group II than in Group III (P < 0.05) during extubation. It was also lower in Group I than in Group III (P < 0.05) after extubation. Systolic blood pressure was lower in Group I than in Groups II and III (P < 0.001) during extubation. Diastolic blood pressure was higher in Group III than in Groups I and II during extubation (P < 0.001) and after extubation (P < 0.05). Mean arterial pressure was lower in Group I than in Groups II and III (P < 0.001) during extubation, lower in Group II than in Group III (P < 0.05) during extubation and lower in Group I than in Group III (P < 0.05) after extubation.

Conclusion: We found that using esmolol before extubation following coronary artery bypass graft surgery prevents undesirable haemodynamic responses while magnesium reduces undesirable haemodynamic responses but does not prevent them.