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

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

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

Conditions
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Myocardial Injury, Remote Ischemic Preconditioning

Intervention / Treatment
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* Procedure: Modified Remote Ischemic Preconditioning
* Procedure: Control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing heart surgery on cardiopulmonary bypass Patients aged 18 years to 80 years Exclusion Criteria: Inability to give informed consent Cardiogenic shock Cardiac arrest on current admission Left ventricular ejection fraction less than 30% Current atrial fibrillation Preoperative use of inotropics or mechanical assist device Patients with significant hepatic dysfunction (Prothrombin>2.0 ratio) Patients with known renal failure with a GFR<30 mL/min/1.73 m2 Patients with significant pulmonary disease (FEV1<40% predicted) Recent myocardial infarction (within 7 days) Recent systemic infection or sepsis (within 7 days) Severe stroke (within 2 months) Significant peripheral arterial disease affecting the upper limbs Previous serious psychiatric disorders (e.g. schizophrenia, dementia) Surgeries: cardiac transplantation, concomitant carotid endarterectomy , previous heart surgery,off-pump surgery, emergency surgery

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Modified Remote Ischemic Preconditioning(mRIPC)<br>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. | Procedure: Modified Remote Ischemic Preconditioning<br>* mRIPC will be induced at 24 h, 12 h and 1 h before surgery and once before induction of anesthesia by 3 cycles of 5-min upper limb ischemia and 5-min reperfusion using a blood-pressure cuff inflated to a pressure 200mmHg<br>* Other names: mRIPC;|
| Placebo Comparator: Control<br>Control group without remote ischemic preconditioning | Procedure: Control<br>* Control group witnout remote ischemic preconditioning<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Troponin I serum release over 24 hours after surgery |  | 24 hours post surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaO2/FiO2 ratio over 24 hours after surgery |  | 24 hours post surgery | 
| salveolar-arterial oxygen gradient over 24 hours after surgery |  | 24 hours post surgery | 
| Inotrope score |  | 12 hours post surgery |