Analysis Of Risk Factors And Prevention Of Low Cardiac Output Syndrome After Off-pump Coronary Artery Bypass Grafting

Objective: To explore the independent risk factors and outcome of low cardiac output syndrome(low cardiac output syndrome,LCOS)after off-pump coronary artery bypass grafting(off-pump coronary artery bypass grafting,OPCABG)in adults,and to provide evaluation basis for reducing the incidence and mortality of LCOS after operation.Methods: 1.The clinical data of 765 patients who underwent OPCABG in the Department of Cardiovascular surgery of the affiliated Hospital of Qingdao University from May 2018 to July 2020 were retrospectively collected.They were divided into LCOS group and non-LCOS group according to the occurrence of LOCS after operation.After consulting the relevant literature at home and abroad,the following indicators were selected for key analysis: 1)General data: sex,age,body mass index,hypertension,diabetes,hyperlipidemia,smoking history,carotid artery stenosis or occlusion,cerebral infarction history.2)preoperative data:ejection fraction,left ventricular end-diastolic diameter,oxygen partial pressure,carbon dioxide partial pressure,oxygen saturation,creatinine,glutamic pyruvic transaminase,glutamic oxaloacetic transaminase,lactic acid,high sensitivity troponin,time from myocardial infarction to operation;3)intraoperative data: operation time,blood transfusion,blood loss,number of vascular remodeling,use of internal mammary artery,accident(including only ventricular fibrillation or cardiac arrest).After screening out the indicators with statistical differences between the two groups,univariate analysis and multi-factor logistic regression analysis were carried out to determine the independent risk factors.2.The clinical data of patients with LCOS diagnosed after OPCABG in Nanyuan District of affiliated Hospital of Qingdao University from May 2018 to July 2020 were collected retrospectively.The patients were divided into death group and survival group according to hospital death or survival.The total hospitalization time,extracardiac intensive care unit time and ventilator intubation time of the two groups were calculated respectively.2)postoperative biochemical indicators:creatinine,glutamic pyruvic transaminase,glutamic oxaloacetic transaminase,partial pressure of oxygen,partial pressure of carbon dioxide,lactic acid,high sensitivity troponin T(3)number of mechanical circulatory aids: such as intra-aortic balloon pulsation,continuous renal replacement therapy,extracorporeal membrane oxygen and;4)cardiotonic drugs such as dopamine,isoproterenol,epinephrine,norepinephrine,milrinone,levosimendan.5)the ejection fraction and left ventricular end-diastolic diameter in the survival group were collected before operation,1 month and 1 year after discharge,and 6)the direct cause of death in the death group was calculated.To analyze the related risk factors of death in patients with LCOS after OPCABG.3.The clinical data of patients who were successfully discharged after OPCABG in the South Hospital of the affiliated Hospital of Qingdao University from May2018 to July 2020 were retrospectively collected.According to the occurrence of LCOS in the hospital,the patients were divided into low cardiac output group and non-low cardiac output group.1)total hospitalization time,extracardiac intensive care unit time and ventilator intubation time.2)postoperative biochemical indicators: creatinine,glutamic pyruvic transaminase,glutamic oxaloacetic transaminase,partial pressure of oxygen,partial pressure of carbon dioxide,lactic acid,high sensitivity troponin T)number of mechanical circulatory aids: such as intra-aortic balloon pulsation,continuous renal replacement therapy,extracorporeal membrane oxygen and extracorporeal membrane oxygen.4)the use of cardiotonic drugs: such as dopamine,isoproterenol,epinephrine,norepinephrine,milrinone,levosimendan;5)ejection fraction and left ventricular end-diastolic diameter in Doppler echocardiography before operation,1 month and 1 year after operation.Through the comparison of the above-mentioned indexes between the two groups of patients with II,the effects of LCOS after OPCABG on the short-and medium-term ejection fraction and left ventricular end-diastolic diameter of patients discharged from OPCABG were analyzed.Results: 1.Among the 765 patients who underwent isolated OPCABG surgery in our center from May 2018 to July 2020,99 cases developed LCOS after operation,with an incidence of12.94%.Univariate analysis showed that ejection fraction,left ventricular end-diastolic diameter,smoking history,carotid artery stenosis or occlusion,cerebral infarction,intraoperative accident,operation time,intraoperative blood transfusion and intraoperative blood loss were related risk factors of LCOS.Multivariate Logistic regression analysis showed that ejection fraction,intraoperative blood loss,smoking history,carotid artery stenosis or occlusion were significantly different between LCOS group and non-LCOS group,which were independent risk factors for LCOS after isolated OPCABG.2.99 patients with LOCS occurred after OPCABG in our center from May 2018 to July 2020,of which 35 patients died in hospital and 64 patients survived and discharged from hospital.The mortality rate in LCOS group was35.35%.The total hospital stay,extracardiac intensive care unit time and ventilator intubation time in death group were higher than those in survival group.The types of vasoactive drugs,positive inotropic drugs and mechanical aids used in the death group were significantly more than those in the survival group,and the main causes of death in the death group were cardiogenic death or multiple organ failure.3.From May 2018 to July 2020,765 OPCABG operations were performed in the center,including 45 patients in the low cardiac output group and 599 patients in the non-low cardiac output group.the total hospital stay,extracardiac intensive care unit time and ventilator intubation time in the low cardiac output group were higher than those in the non-low cardiac output group.The postoperative application rate of vasoactive drugs was higher in the low cardiac output group,and the improvement of shortand medium-term ejection fraction and left ventricular end-diastolic diameter in the low cardiac output group was worse than that in the non-low cardiac output group.Conclusion: 1.Left ventricular ejection fraction,intraoperative blood loss,smoking history,carotid artery stenosis or occlusion were independent risk factors for LCOS after OPCABG alone.2.Long total hospital stay,long time in extracardiac intensive care unit,long intubation time of ventilator,poor biochemical indexes and poor improvement of cardiac function were the risk factors of death in patients with LCOS after OPCABG perioperative period;Cardiogenic factors are the main cause of death in LCOS patients after OPCABG.3.One month and one year after discharge,the ejection fraction and left ventricular end-diastolic menstruation in patients with LCOS after OPCABG were lower than those without LCOS after OPCABG.