Dexmedetomidine and Magnesium Sulfate in Preventing Junctional Ectopic Tachycardia After Pediatric Cardiac Surgery

Study Overview
=================
Brief Summary
-----------------
to study the prophylactic effect of magnesium sulfate , dexmedetomidine or their combination in reduction the incidence of JETS postoperative

Detailed Description
-----------------
Following approval from research and ethics committee, preoperative preparation, and anesthesia inductuion. the baseline heart rate (HR) and blood pressure (BP) will be recorded. The patients will be divided into three groups according to the type of drug injected. Group MD (dexmedetomidine Mgso4 group): include (40 ) patients and will receive dexmedetomidine 0.5 µg/kg diluted in 50 mL of normal saline intravenously over 20 minutes, After induction followed by 0.5 µg/kg per hour infusion for 72 hours postoperatively or ready for extubation prior to 72 hour time period (Precedex ; Hospira Worldwide ,Lake Forest, IL).(20) and receiving Magnesium Sulfate (50 mg/kg) bolus administered at the time of Aortic Cross Clamp Release. with continued administration for 72 hours postoperatively at a dose of 30 mg/kg/day.(21) Group D (dexmedetomidine group): include (40 ) patients and will receive the same of dexmedetomidine as MD group in addition to normal saline instead of Magnesium Sulfate . Group C (control group): include (40 ) patients and will receive normal saline instead of dexmedetomidine and MgSo4 . after the end of the procedure, inhalational anesthetics will be stopped as well the muscle relaxant. The patient will be transferred to the ICU. In ICU , the post-operative rhythm was monitored to detect the early incidence of arrythmia Diagnostic criteria for JET included the following: Tachycardia with QRS similar to sinus rhythm QRS A ventricular rate more than 170 beats/min AV dissociation with or without hemodynamic compromise A ventricular rate faster than the atrial rate. (8) Early onset postoperative JET was defined as the presence of JET during the first 72 h postoperatively. Continuous ECG monitoring will be used continuously in the PCCU. Standard 12-lead ECG will be registered in all patients preoperatively and at the time of PCCU admission. When JET was detected on the ECG monitor this will be also documented with a standard ECG strip Patients who developed JET and were hemodynamically unstable were managed with mild hypothermia, reduction in inotropes, magnesium, digoxin, and amiodarone.

Official Title
-----------------
Efficacy of Dexmedetomidine and Magnesium Sulfate in Preventing Postoperative Junctional Ectopic Tachycardia After Pediatric Cardiac Surgery: Randomized Controlled Trial

Conditions
-----------------
Post Operative Arrythmia

Intervention / Treatment
-----------------
* Drug: Dexmedetomidine
* Drug: Magnesium sulfate


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age: less than 5 yrs. Weight: more than 5 kg . Pathology :A-V canal ,VSD ,ASD undergoing corrective surgery with normal sinus rhythm, and stable hemodynamics. Exclusion Criteria: a history of arrhythmias within the last 6 months, current use of antiarrhythmic medication such as amiodarone, digoxin. patients with pacemaker or atrioventricular (A-V) block. known allergy to dexmedetomidine or magnesium sulfate. patients with a history of re-do surgery.

Ages Eligible for Study
-----------------
Minimum Age: 6 Months
Maximum Age: 5 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: control group<br>patients will receive normal saline instead of dexmedetomidine and MgSo4 . | |
| Active Comparator: dexmedetomidine group<br>patients will receive the same of dexmedetomidine as MD group in addition to normal saline instead of Magnesium Sulfate . | Drug: Dexmedetomidine<br>* dexmedetomidine 0.5 µg/kg diluted in 50 mL of normal saline intravenously over 20 minutes, After induction followed by 0.5 µg/kg per hour infusion for 72 hours postoperatively or ready for extubation prior to 72 hour time period<br>* Other names: Precedex;|
| Active Comparator: Dexmedetomidine Mgso4 group<br>patients will receive dexmedetomidine 0.5 µg/kg diluted in 50 mL of normal saline intravenously over 20 minutes, After induction followed by 0.5 µg/kg per hour infusion for 72 hours postoperatively or ready for extubation prior to 72 hour time period (Precedex ; Hospira Worldwide ,Lake Forest, IL).(20) and receiving Magnesium Sulfate (50 mg/kg) bolus administered at the time of Aortic Cross Clamp Release. with continued administration for 72 hours postoperatively at a dose of 30 mg/kg/day | Drug: Dexmedetomidine<br>* dexmedetomidine 0.5 µg/kg diluted in 50 mL of normal saline intravenously over 20 minutes, After induction followed by 0.5 µg/kg per hour infusion for 72 hours postoperatively or ready for extubation prior to 72 hour time period<br>* Other names: Precedex;Drug: Magnesium sulfate<br>* Magnesium Sulfate (50 mg/kg) bolus administered at the time of Aortic Cross Clamp Release. with continued administration for 72 hours postoperatively at a dose of 30 mg/kg/day.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of postoperative JET | Incidence of postoperative JET for 72 hours postoperatively. | for 72 hours postoperatively. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Vasoactive - inotropic score | Inotropic score = (dopamine × 1) + (dobutamine × 1) + (adrenaline × 100) + (noradrenaline × 100) + (milrinone × 10). Dosages of above drugs were in mcg/kg/min | for 72 hours postoperatively. | 
| prognostic indices | • time to extubation ( in hours), ICU stay (in days) , and hospital stay (in days) | for 72 hours postoperatively. |