Tidal Volume Of Right Heart Function Of Patients With Mechanical Ventilation In Observational Studies

Objective:This study was to explore the influence of tidal volume of right heart function.Methods: This study included the patients in June 2015 to December 2015,Respiratory failure caused by various reasons,give invasive mechanical ventilation treatment more than 24 hours in the fourth hospital affiliated to Hebei medical university Intensive Care Unit?ICU?.Inclusion criteria: Patients who had respiratory failure and need for invasive mechanical ventilation,all patients needed older than the 18 years old.Exclusion criteria: Patients with chronic corpulmonale patients?acute pulmonary embolism?Right ventricular infarction?Maternal and nursing mothers?Age < 18 years old?Couldn't get clear echocardiographic images.The competent physicians decide Ventilator parameters;Collect patients' basic information,mainly including: height,standard weight;Clinical and laboratory parameters,mainly including: body temperature,heart rate,blood pressure,central venous blood oxygen saturation,arterial blood gas analysis;Respirator parameters,mainly including tidal volume?VT?,airway peak pressure?Ppeak?,average airway pressure?Pmean?,respirator model and parameters.Give each patient heart ultrasonic monitoring,including: right ventricular end-diastolic area/left ventricular end-diastolic area?RVarea/LVarea?,tricuspid annulus plane systolic excursion?TAPSE?,The right ventricle diastolic early stage peak?E?,The right ventricle diastolic late stage peak?A?and myocardium of the early diastolic velocity?E?,the interventricular septum abnormality movement,the systolic pulmonary artery pressure?PASP?,inferior vena cava?IVC?.Collected the dates every day,until weaning from mechanical ventilation or therapy for 7 days.According to whether the diagnosis of ARDS,the patients were divided into ARDS or not-ARDS group;A according to the mean tidal volume/standard weight,the two groups patients were divided into S/L respectively;ARDS group with 6 ml/kg of tidal volume for the boundary value,divided into less than or equal to 6 ml/kg?S6 group?,greater than 6 ml/kg?L6 group?;The ARDS patients with 8 ml/kg of tidal volume for the boundary value,divided into less than or equal to 8 ml/kg?S8 group?less than or equal to,greater than 8 ml/kg?L8 group?.To assess the effect of different tidal volume on the right heart function,including: right ventricular size,right ventricular systolic and diastolic function,before and after loading,at the same time observation and analysis of the influence of different tidal volume on the prognosis of patients,including: the mechanical ventilation time,28 days,the fatality rate of ICU in the hospital and the total number of days in hospital.Results: 1 84 patients were included in this study,43 patients with ARDS: S6 group had 19 patients,L6 group had 24 patients;41 patients with not-ARDS: S8 group had 24 patients,L8 group had 17 patients;A total of 43 patients,given low tidal volume of lung protective ventilation,accounting for 51.2% of the total.2 Different tidal volume of right heart function and prognosis in patients with ARDS group 2.1 The baseline characteristics between the groups in S6 and L6 group SOFA?APACHEII scores ?plasma lactate had no statistical difference in S6 and L6 groups?P > 0.05?.According to the arterial blood gas analysis?into the ICU for six hours?showed that pH?PaCO₂?PaO₂?PaO₂ / FiO₂,had no statistical difference in the two groups?P > 0.05?.According to the ultrasound findings?into the ICU for six hours?,two groups of patients with TAPSE,RVarea/LVarea,E/A,E/E,PASP,IVC no statistical difference?P > 0.05?,between the two groups were comparable.2.2 In total,44.2% of patients with ARDS given low tidal volume ventilation.2.3 After giving positive pressure ventilation,the TAPSE were decreased in S6?L6 groups.Positive pressure ventilation time after 48 h,TAPSE in L6 group patients was lower than that in S6 group [18.20±4.76 vs 15.30±3.37 mm],the difference is statistically significant?P = 0.043?2.4 The two groups had no significant difference in RVarea/LVarea?E/A?E/E?PASP?IVC diameter?P > 0.05?2.5 The two groups had no significant difference in Length of ICU stay and Length of hospital stay?P >0.05?.L6 group 28 days mortality higher than the S6 group?P=0.014?.3.1 The baseline characteristics between the groups in S8 and L8 group SOFA?APACHEII scores ?plasma lactate had no statistical difference in S8 and L8 groups?P > 0.05?.According to the arterial blood gas analysis?into the ICU for six hours?showed that pH?PaCO₂?PaO₂?PaO₂ / FiO₂,had no statistical difference in the two groups?P > 0.05?.According to the ultrasound findings?into the ICU for six hours?,two groups of patients with TAPSE,RVarea/LVarea,E/A,E/E,PASP,IVC no statistical difference?P>0.05?,between the two groups were comparable.3.2 In total,58.5% of patients with not-ARDS given low tidal volume ventilation.3.3 After giving positive pressure ventilation,the TAPSE were decreased in S8?L8 groups.But there were no difference in the two group?P>0.05?.3.4 The two groups had no significant difference in RVarea/LVarea?E/A?E/E?PASP?IVC diameter?P>0.05?3.5 The two groups had no significant difference in 28 days mortality ?Length of ICU stay and Length of hospital stay?P>0.05?.4 The comparison of TAPSE in patients with low tidal volume ventilation in ARDS or not-ARDS group 4.1 SOFA?APACHEII scores ?plasma lactate had no statistical difference in S6?S8 group?P>0.05?;According to the arterial blood gas analysis?into the ICU for six hours?,S6 group PaO₂ / FiO2 was lower than that in group S8 [146.7?71.10?vs 206.01?120.87?],the difference has statistical significance?P = 0.005?.Two groups of patients with TAPSE,didn't have statistical difference?P > 0.05?.4.2 After given positive pressure ventilation 3 days,the TAPSE had no difference in the two group?P > 0.05?.5 The comparison of TAPSE in patients with high tidal volume ventilation in ARDS or not-ARDS group 5.1 APACHEII scores ?plasma lactate had no statistical difference in L6?L8 group?P > 0.05?;According to the arterial blood gas analysis?into the ICU for six hours?,L6 group PaO2 / FiO₂ was lower than that in group L8 [153.77?62.99?vs 218.83?214.25?],the difference has statistical significance?P = 0.005?.L6 group SOFA was higher than that in group L8 [6.0?4.5?vs 4.0?2.5?],the difference has statistical significance?P=0.016?.5.2 After given positive pressure ventilation 3 days,the TAPSE had no difference in the two group?P > 0.05?.6 Consider the influence factors in the study,we found that Sepsis,positive expiratory end pressure?PEEP?,Mean airway pressure?Pmean?,liquid balance has no influence on the three group?P value were 0.421,0.257,0.281,0.661?.Conclusion:1 Not yet for all patients with positive pressure ventilation,give low tidal volume of lung protective ventilation.The implementation of low tidal volume ventilation remains to be perfect.2 For ARDS patients,48 hours,tidal volume mechanical ventilation is greater than 6 ml/kg body weight,which can lead to right heart systolic dysfunction.Limit tidal volume in under 6 mL/kg body weight,28 days could reduce the patient mortality.3 In the existing conditions,regular monitor the Tricuspid annular plane systolic excursion?TAPSE?,can be used as mechanical ventilation patients to assess effect of positive pressure ventilation contraction to right heart function.