Cardiopulmonary Protective Effects of Modified Remote Ischaemic Preconditioning in Mitral Valve Replacement Surgery

Cardiopulmonary Protection of Modified Remote Ischaemic Preconditioning in Mitral Valve Replacement Surgery

During cardiac surgery with cardiopulmonary bypass , injury occurs to the heart muscle and the lung.The heart and lung injury is a serious complication ,which increases both mortality and morbidity of cardiac surgery .Remote ischemic preconditioning(RIPC) with transient upper limb ischemia/reperfusion is a novel, simple, cost-free,non-pharmacological and non-invasive strategy.Recent some trials suggested that RIPC could provide myocardial protection by reducing serum cardiac biomarkers,however, more recent multicenter studies[9-11] had failed to show the protective effects of RIPC with respect to the troponin release and lung injury.

Remote ischemic preconditioning (RIPC) is reported to have the early-phase and delayed-phase organ protective effects, whether the modified RIPC protocol induced repeatedly has the cardiopulmonary protective effect is still uncertain.

modified RIPC was induced at 24 h, 12 h and 1 h before surgery to reinforce the protective effects of RIPC.The single RIPC protocol was induced by three cycles of upper-limb ischemia, a standard blood-pressure cuff was placed on the ringt upper arm, then inflated the cuff to 200 mm Hg for 5 minutes, followed by 5 min of cuff deflation.

Inclusion Criteria:

1. Patients undergoing heart surgery on cardiopulmonary bypass
2. Patients aged 18 years to 80 years

Exclusion Criteria:

1. Inability to give informed consent
2. Cardiogenic shock
3. Cardiac arrest on current admission
4. Left ventricular ejection fraction less than 30%
5. Current atrial fibrillation
6. Preoperative use of inotropics or mechanical assist device
7. Patients with significant hepatic dysfunction (Prothrombin>2.0 ratio)
8. Patients with known renal failure with a GFR<30 mL/min/1.73 m2
9. Patients with significant pulmonary disease (FEV1<40% predicted)
10. Recent myocardial infarction (within 7 days)
11. Recent systemic infection or sepsis (within 7 days)
12. Severe stroke (within 2 months)
13. Significant peripheral arterial disease affecting the upper limbs
14. Previous serious psychiatric disorders (e.g. schizophrenia, dementia)
15. Surgeries: cardiac transplantation, concomitant carotid endarterectomy , previous heart surgery,off-pump surgery, emergency surgery