Myocardial Reperfusion Injury
Conditions
Brief summary
The purpose of this study is to determine whether Glyceryl Trinitrate (GTN) reduces injury to the heart during heart-lung bypass surgery in combination with the newer technique of remote ischaemic preconditioning (RIPC).
Detailed description
Ischaemic heart disease is a leading cause of mortality in the western world. A number of patients undergo coronary artery bypass graft (CABG) surgery as treatment for ischaemic heart disease. With the rise of interventional procedures, patients who are coming to have CABG surgery are higher risk1. Remote ischaemic preconditioning (RIPC) has been shown to reduce perioperative myocardial injury (PMI) in patients having CABG even when cold blood cardioplegia or intermittent cross clamp fibrillation is used as cardioprotective measures. These patients have a general anaesthetic with multiple infusions including Glyceryl Trinitrate (GTN). The use of GTN in these patients is based on theoretical assumptions of coronary vasodilation pre operatively along with maintaining graft potency postoperatively. We intend to investigate the effect of GTN in patients undergoing cardiac surgery being subjected to RIPC in its role as a Nitric Oxide (NO) donor. Exogenous NO has been shown to be cardioprotective in animal models.
Interventions
3 cycles of 5 minutes to arm and legs
DRUGIV Normal saline
Normal saline IV started prior to knife to skin at a rate of 2-5 mls/h and stopped just after weaning off bypass.
DRUGIV Glyceryl trinitrate 2-5ml/h
IV GTN given during surgery started prior to knife to skin and stopped after weaning off cardiopulmonary bypass.
Sponsors
University College London Hospitals
University College, London
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age \> 18 years all patients admitted for on- pump CABG and/or valve surgery * Able to give consent
Exclusion criteria
* Allergies to excipients of IMP and placebo * Chronic Renal failure (eGFR\<30 ml/min/kg) * Severe liver disease * Peripheral arterial disease * Pregnant or lactating women
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Troponin T area under the curve | 72 hours | Troponin T area under the curve will be calculated using blood samples collected at 0,6,12,24,48 and 72 hours plotting it against time to calculated AUC. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Ventilator dependence post operatively | Post-operative day 1,2,3 and 4 | The duration of endotracheal intubation will be noted in hours. Re-intubation rates will be calculated by noting down the number of patients requiring re-intubation and comparing this amongst the 4 groups. |
| Incidence of Acute Kidney Injury assessed using biomarkers | Post-operative day 1,2,3 and 4 | Serum creatinine levels will be noted in the first 3 days postoperatively. If a patient requires renal replacement therapy, this will be recorded and comparisons made amongst the groups. Hourly urine output and daily urine volumes for the duration of ITU stay will be recorded. |
| Inotrope/Vasopressor requirements peri-operatively | Post-operative day 1,2,3 and 4 | The inotrope score will be calculated as follows: Dosages (in μg/kg/min) of \[Dopamine + Dobutamine\] + \[(Adrenaline + Noradrenaline + Isoproterenol + Isoproterenol) x 100\] + \[(Enoximone + Milrinone) x 15\] |
| Length of hospital stay | Average 14 days | Duration of hospital stay will be recorded in days |
| Incidence of post-operative atrial fibrillation | Post-operative day 1,2,3 and 4 | Atrial fibrillation will be diagnosed using ECG. A record of the number of patients developing AF post operatively, the intervention used to treat it and whether or not the patient reverted to sinus rhythm prior to ITU discharge will be documented |
| Length of ITU stay | Average 4 days | A record of stay in days will be noted |
Countries
United Kingdom
Outcome results
None listed