The Impact Of The Levels Of Brain Natriuretic Peptide In Plasma By Invasive Positive Pressure Ventilation And Noninvasive Positive Pressure Ventilation In Patients With Respiratory Failure

ObjectiveAs an important Cardiac markers,Brain Natriuretic Peptide(BNP)involved in the pathophysiology of the cardiovascular system process.BNP is an important component of the field in cardiovascular endocrine.BNP in the regulation of blood pressure,fluid balance and cardiovascular function plays an important role.Such as ventricular wall tension and pressure overload can stimulate the synthesis,secretion,the release of BNP. The BNP can be instantaneous synthesis,secretion,release,so it can reflect directly proportional to the severity of the disease.The biological half-life of BNP in the blood cycle is about 23 minutes.Thus the adoption of short-term changes in the concentration of plasma BNP observed various intervention become possible. Corresponding to the rapid synthesis and rapid removal of the characteristics of BNP, the process of change and the role of BNP in acute diseases was relatively small studied. The changes and significance of the concentrations of plasma BNP in patients with respiratory failure in the mechanical ventilation(Mv)was extremely small studied. Based on the above reasons we designed this study,the purpose of it was observing BNP in acute respiratory failure and acute stage of chronic respiratory failure during Mv in the plasma concentration changes and trying to analyse the reasons for the changes and significance. MethodsA self-control and non-randomized concurrent controlled trial conducted in a 16-bed emergency intensive care unit of first affiliated hospital of China Medical University.From October 2006 to September 2007,twenty seven Mv patients were included.By invasive and non-invasive ventilation indications these patients were divided into groups A and B.Six patients suitable for the inclusion and exclusion criteria were treated by both Invasive positive pressure ventilation(IPPV)and Noninvasive positive pressure ventilation(NIPPV).They were recorded separately in the two groups.Therefore,the total number of cases was 33 cases.Group A connectted invasive ventilator.Group B connectted non-invasive ventilator.Before Mv and after two hours of Mv,2ml of blood were collected in both group A and B to Detect concentrations of plasma BNP.After two hours of adjusting parameters in treatment period include 12 patients in group A and Ventilator weaning include 10 patients in group A,2ml of blood were collected too.At the same time,blood gas analysis values and show few on the Monitor were Recorded.Few showed on the Ventilator was Recorded in the same time too.And through V_T,P_peak,PEEP Calculated dynamic compliance(Cdyn =V_T/(P_peak—PEEP)).Plasma BNP concentration was determined by ELISA method.Results(1)To acute respiratory failure and acute stage of chronic respiratory failure patients,the early BNP concentration(527.97±198.72)pg / ml was significantly higher than the Recognized normal reference value(＜90 pg / ml)(t=12.661, P=0.000).(2)IPPV before and IPPV two hours,the concentration of plasma BNP were (524.24±215.57)and(314.47±105.83)pg / ml.There were significant differences between IPPV before and IPPV two hours(t=4.546,P＜0.001).Before NIPPV and NIPPV two hours,BNP were(536.55±163.41)and(524.03±186.96)pg/ml(t=0.373, P=0.718).Comparing BNP between IPPV two hours and NIPPV two hours,the former was lower than the latter(F=4.850,t=-4.113,P＜0.001).But the difference between IPPV before and NIPPV before had no statistically significant(F=0.925,t=-1.80, P=0.859).To 12 patients in group A,the concentration of BNP in IPPV before,IPPV two hours and adjustment parameters two hours,were(461.39±205.19),(300.89±115.65), (201.16±72.10)pg/ml.Comparing the latter with the first two,the differences had statistically significant(t=5.003,4.165 All P＜0.05).To 10 successful weaning patients in group A,the concentration of BNP in IPPV before,IPPV two hours and after weaning were(564.08±273.05),(294.17±85.83), (437.13±113.21)pg/ml.The later two had a significant difference(t=-3.567, P=0.006).After weaning,BNP dropped 22.51%than IPPV before.But the difference had no statistically significant(t=1.959,P=0.082).(3)To the dead patients after IPPV in group A,BNP in IPPV before and IPPV two hours were(489.79±182.11),(437.10±90.92)pg/ml.And in Survival of patients after IPPV in group A,the concentration were(556.01±246.36)and(273.55±92.98) pg/ml.There were significant differences at IPPV two hours(F=0.432,t=3.357, P=0.011).But,before IPPV,the difference had no statistically significant(F=0.589, t=-0.612,P=0.554).(4)The margin of the concentration of BNP was negatively correlated with that of PaO2(r=-0.468,P=0.024).And it was positively correlated with Cdyn(r=0.421, P=0.046).Conclusions(1)Respiratory failure BNP have been significantly increased,suggesting that respiratory failure has been accompanied by changes in heart function.(2)The concentration of BNP decrease significantly in the treatment of IPPV.This decrease is directly linked with PEEP.With the increase in PEEP further reduce BNP. But,comparing NIPPV before and NIPPV two hours,there is little change in BNP. BNP is the marker of cardiac function.So that IPPV can significantly reduce heart load and NIPPV does neither reduce nor increase the heart load.On the mechanical ventilation of respiratory failure IPPV reduce heart stress is superior to the role of NIPPV。(3)Plasma concentrations of BNP can directly reflect not only changes in the function of the heart,can also indirectly reflect in patients of IPPV with mechanics of breathing.(4)The Lower rates of the concentration of plasma BNP can be used as prognostic.