Background and Objective
Spinal cord ischemia with subsequent paraplegia secondary to aortic coarctation repair procedures is rare, but it has serious consequences that can affect quality of life. Infrared spectroscopy (NIRS) is used for non invasive spinal cord oxygenation monitoring to estimate cord perfusion and detect early cord ischemic changes. Several pharmacological agents have been used to improve cord perfusion, the main action of these agents is to improve regional/systemic perfusion and decrease ICP. In the current study, we studied magnesium sulphate and levosimendan for their vasodilating effect that might improve spinal cord perfusion as part of spinal cord protection.
Methods
Forty two infants undergoing aortic coarctectomy under general anaesthesia were registered in double blinded randomized controlled study, three groups were included; group C received i.v. saline, group L received levosimendan in loading dose 6ug/kg i.v. for 15 minutes then maintenance dose 0.1 ug/kg/min till end of surgery and group M received levosimendan in loading dose 6 ug/kg i.v. for 15 minutes then maintenance dose 0.1 ug/kg/min in combination with magnesium sulphate in loading dose 25 mg/kg i.v. for 15 minutes then maintenance dose 10 mg/kg/hr till the end of surgery. The vital signs and NIRS values assessed before, during and after clamping of aorta.
Results
All baseline demographic data were comparable among all groups except for height (cm), which was significantly lower in Group L compared to Group C ( = 0.013). NIRS values were comparable among the three groups throughout experimental protocol except after cross clamp at 20 minutes, where Group M was significantly higher compared to group C ( = 0.007).Heart rate, mean arterial blood pressure, total fluid intake, urine output, aortic cross clamp time and surgical time was comparable among all groups, were comparable among 3 studied groups.
Conclusion
Adding magnesium sulphate to levosimendan has showed improvement in spinal cord perfusion during cross clamping as monitored by NIRS when compared to use of levosimendan alone or placebo in coarctectomy operations without affecting hemodynamics.