Aim of the work: to evaluate the effect of intravenous dexmedetomidine infusion on patients
undergoing open heart surgery regarding stress response markers as plasma interleukin-6 and
plasma cortisol.
Patents and Methods: Fifty consecutive patients aged 18-70years, scheduled for elective open
heart surgery using CPB technique were enrolled in this study at the Cardiothoracic Surgery Unit,
Luxor international hospital, from July 2018 to May 2019. Patients randomly assigned using closed
envelope technique into two equal groups according to the drug infused intraoperatively: 1st group < br />(25 patients):- Dexmedetomidine group (Group D); received loading dose of intravenous
dexmedetomidine infusion of 1 μg/kg IV dissolved in 20ml normal saline over 10 minutes followed
by maintenance dose of 0.5 μg/kg/hr. till the end of surgery where 0.5 μg /kg/h was calculated for
each patient and dissolved in 12.5 ml normal saline 2nd group ( 25 patients):- placebo group (Group < br />P); receive 20ml intravenous infusion of normal saline 0.9 % over 10 minutes followed by
continuous infusion of 12.5 ml of normal saline till the end of surgery.
Results: Our study revealed that HR and MAP wasn't significantly different between the two
groups at the baseline, but significantly lowered in Dex. group after induction, during CPB, post
CPB, and postoperative.Dexometomedine suppress the intraoperative and postoperative rise of IL-6
which was significantly higher in placebo group relative to Dex. group. Also dexometomedine has
effect on stress hormone as serum cortisol and serum glucose decease in Dex. group relative to
placebo group. None of studied cases revealed bradycardia or hypotention and there are no
significant difference between groups regarding side effect drowsiness, nausea and vomiting
Conclusion: This study demonstrated that the continuous administration of dexmedetomidine
during open heart surgery with CPB suppressed intraoperative and post-operative cytokine
secretion, and improved post-operative inflammatory response indices in the present study. Also it
stabilize blood pressure and heart rate and blunt cardiovascular response to CPB. These results
could be attributed to the anti-inflammatory effects of dexmedetomidine.