Adenosine Versus Verapamil for Management of Supraventricular Tachycardia Post- Coronary Artery Bypass Grafting
Condition: Supraventricular Tachycardia
MeSH terms: Tachycardia; Tachycardia, Supraventricular
Study type: Interventional

Summary: 
      This prospective study was conducted in 268 patients aged from 65-70 years posted for
      coronary artery bypass grafting. Patients were randomly allocated to either adenosine or
      verapamil(control) groups. In the adenosine group, patients received IV adenosine 6 mg bolus
      then wait 2 minutes, if it failed to return to sinus rhythm then another 12 mg IV bolus of
      adenosine was administered, if supraventricular tachycardia persisted then the patient was
      shifted to verapamil. In verapamil group, patients received IV verapamil 5mg bolus slowly
      over 2 minutes followed by a second IV bolus dose of 5 mg ,10 minutes after the initial dose
      in case of persistence of supraventricular tachycardia (SVT). If SVT persisted, the patient
      was shifted to adenosine. The efficacy of the study drug, ICU stay length, systolic blood
      pressure, hospital- stay length, duration of extubation, the total dose of the study drug
      used, the total cost of the study drugs and the incidence of adverse events were recorded.
    

Detailed description: 
      Written informed consent was obtained from every patient. This prospective, double-blind,
      parallel-group clinical trial was conducted in 268 patients. The following inclusion criteria
      were used: (1) RCT; (2) adult (age: 65-70 years) patients with ASA physical status II and
      III, scheduled for elective isolated CABG; (3) use of adenosine versus verapamil for
      treatment of postoperative supraventricular tachycardia; (4) the efficacy was a mandatory
      outcome measurement ; (5) Ejection fraction 50-60%; (6) Absence of any associated
      comorbidities or history of myocardial infarction. Patient with impaired cerebral Perfusion,
      hemodynamic instability arrhythmias other than PSVT were excluded.

      Anesthesia management was standardized to minimize any effect of anesthetic type on
      hemodynamics. Premedication with midazolam was limited to a maximum of 0.05 mg/kg. Anesthesia
      was induced with 12 μg/kg fentanyl, 5-7 mg/kg thiopental sodium, and 0.15 mg/kg pancuronium
      and was maintained with 1-2.0% isoflurane. Heart rate and blood pressure were maintained
      within 20% of the baseline values. Anticoagulation was achieved with heparin 300 U/kg
      administered into the right atrium to maintain an activated clotting time above 480 s.
      Cardiopulmonary bypass (CPB) was conducted with non-occlusive roller pumps, membrane
      oxygenators, arterial line filtration, and cold blood-enriched hyperkalemic arrest. The CPB
      circuit was primed with 1.8 l lactated Ringer's solution and 50 ml of 20% mannitol.
      Management of CPB included systemic hypothermia (to an esophageal temperature of 32°C) during
      aortic cross-clamping, targeted mean perfusion pressure between 60 and 80 mmHg, and pump flow
      rates of 2.2 l/min/m2. Myocardial protection was achieved with antegrade cold blood
      cardioplegia. A 32-μm filter (Avecor Affinity, Minneapolis, MN, USA) was used in the arterial
      perfusion line. Before separation from CPB, patients were warmed to 36-37°C. After separation
      from CPB, heparin was neutralized with protamine sulfate and 1 mg/100 U heparin to reach an
      activated clotting time within 10% of baseline. All patients were transferred to the ICU
      after surgery.

      Patients were randomly allocated to either adenosine or verapamil(control) groups according
      to a computer-generated randomization code, with allocation ratio 1:1. Opaque sealed
      envelopes were prepared according to the randomization schedule, and were opened by a
      clinician not involved in any part of the study. Upon arrival at the ICU, a standardized
      protocol for postoperative care was implemented for all patients by well-trained nurses
      supervised 1:1and by the ICU consultants. The study medications were calculated and prepared
      by ICU nurses who were not a part of the research team. Both end-point assessors of the
      outcomes and patients were blinded to the study drugs. All staff were blinded to treatment
      allocation excluding the ICU consultant and resident who were not part of the research team.

      To ensure blinding of study drug administration, the medication vials were kept in opaque
      bags. Trial bags were blinded and marked with a unique number. The allocation of trial drugs
      was determined by the web-based randomization system by the allocation of the bag number.

      In the adenosine group, patients received IV adenosine 6 mg bolus then wait 2 minutes, if it
      failed to return to sinus rhythm then another 12 mg IV bolus of adenosine was administered,
      if supraventricular tachycardia persisted then the patient was shifted to verapamil. In
      verapamil group, patients received IV verapamil 5mg bolus slowly over 2 minutes followed by a
      second IV bolus dose of 5 mg ,10 minutes after the initial dose in case of persistence of
      supraventricular tachycardia (SVT). If SVT persisted, the patient was shifted to adenosine.

      All patients were routinely extubated when deemed clinically appropriate according to the
      local ICU protocol, by ICU staff, when the patient was able to maintain spontaneous breathing
      for 48 h, according to normal weaning parameters, after which they were encouraged to sit on
      a chair and mobilize with the assistance of health care providers in the ICU then the
      physiotherapist became responsible for improving mobility and rehabilitation of the patients
      till discharge from the hospital. Systolic blood pressure and heart rate were continuously
      monitored during drug administration and 30 minutes after conversion to sinus rhythm.
    

Intervention name(s): adenosine; verapamil
Intervention type(s): Drug; Drug
Intervention description(s): patients received IV adenosine 6 mg bolus then wait 2 minutes, if it failed to return to sinus rhythm then another 12 mg IV bolus of adenosine was administered, if supraventricular tachycardia persisted then the patient was shifted to verapamil.; patients received IV verapamil 5mg bolus slowly over 2 minutes followed by a second IV bolus dose of 5 mg ,10 minutes after the initial dose in case of persistence of supraventricular tachycardia (SVT). If SVT persisted, the patient was shifted to adenosine
Intervention MeSH terms: Adenosine; Verapamil
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: SVT; CABG; verapamil; adenosine