Early lactate clearance rate in assessing the prognosis of patients with postcardiac surgery undergoing cardiopulmonary bypass / 中国综合临床

ABSTRACT

Objective To investigate the correlation between the prognosis and the early lactate clearance in patients with postcardiac surgery undergoing cardiopulmonary bypass.Methods The clinical data of 73 patients who underwent postcardiotomy undergoing cardiopulmonary bypass in SuBei Hospital of Jiangsu Provience,from March 2006 to February 2010,were prospectively collected and analyzed.The collection data including( 1 ) Preoperative factorsincluding gender,age,diagnosis preoperative,NYHA grade,APACHE Ⅱ score and left ventricular end-diastolic diameter.(2) Operative factorsoperation time,block aorta time.(3)Postoperation factorshemorrhage volume,mechanical ventilation time,and factors of hemodynamics and oxygen metabolism at 6 hour postoperativeheart rate(HR),central venous pressure(CVP),pulmonary capilary wedged pressure( PCWP),cardiac output index( CI),arterial blood lactic acid,6 h lactate clearance,partial pressure of oxygen( PO2 ),mixed venous oxygen saturation ( SvO2 ),oxygen delivery index ( DO2I),oxygen consume index (VO2I),oxygen extraction ratio(O2ext).Patients were divided into survival group,control group,high level of lactate clearance group( lactate clearance rate ＞ 30％ ) and low level of lactate clearance group.Firstly,the data analyzed with process of single variable analysis and some parameters,which showed the significant difference,were sorted out from two groups.Then these parameters were put to the Logistic regression analysis.Consequently,the independent risk factors of death of postcardiac surgery could be found.Results The mortality in high lactate clearance group ( 4.55％ [ 2/44 ] ) was significantly less than the low lactate group (34.48％ [ 10/29] ) ( x2 =11.889,P ＜0.01 ).The single variable analysis had shown that there were significant difference on APACHE Ⅱ score ( [ 16.9 ± 2.9 ] vs [ 19.2 ± 2.6 ],t =2.537 ),left ventricular end-diastolic diameter( [ 53.9 ± 5.6 ] mm vs [ 63.8 ± 4.6 ] mm,t =5.847 ),block aorta time ( [ 101.2 ± 34.2 ] min vs [ 122.7 ±22.7 ] min,t =2.078 ),hemorrhage volume( [464.0 ± 158.8 ] ml vs [ 603.2 ± 159.5 ] ml,t =2.773 ),mechanical ventilation time( [ 22.6 ± 5.1 ] h vs [ 28.8 ± 5.2 ] h,t =3.857 ),arterial blood lactic acid ( [ 3.5 ±1.3 ] mmol/L vs [5.1 ± 1.5 ] mmol/L,t =3.912),lactate clearance ( [38.8 ± 17.4]％ vs [ 14.6 ±9.7]％,t =4.846),and SvO2( [69.1 ±4.2]％ vs [59.2 ±6.9]％,t =5.847) (P＜0.05 or P ＜0.001)between survival group and control group.Multiple regression analysis showed that lactate clearance and left ventricular enddiastolic diameter were the two independent risk factors of death,and the odds ratio(OR) were 7.773 (95％ CI 1.364-44.306,P ＜0.05) and 15.186(95％ CI 2.758-83.162,P ＜0.01).Conclusion Early lactate clearance rate can be used as an important indicator to evaluate the prognosis of patients with postcardiac surgery undergoing cardiopulmonary bypass.