Objective To investigate the serumlevel of endothelin-1 ( ET-1) in patients with acute lung injury/acute respiratory distress syndrome ( ALI/ARDS) and its clinical significance. Methods Thirty-one ALI/ARDS patients received mechanical ventilation in ICUand 25 normal subjects were recruited in the study. The patients who died in two weeks fell in death group, and the patients who did not died in two weeks fell in survival group. The serum level of ET-1 measured by EIA method were compared between thepatients with different severity of lung injury [ evaluated by American-European Consensus Conference on ARDS ( AECC) criteria and lung injury score( LIS) ] , and between the patients with different prognosis ( death or survival ) . The correlation was analyzed between the level of ET-1 and clinical parameters.Results The ET-1 level was higher in the ALI/ARDS patients than that in the control subjects [ ( 6. 18 ±4. 48) ng/L vs. ( 2. 68 ±1. 34) ng/L, P lt;0. 05] . There was no significant difference in the patients with different severity [ ALI vs. ARDS, ( 5. 43 ±4. 39) ng/L vs. ( 7. 01 ±4. 51) ng/L, P gt; 0. 05; LIS≤2. 5 vs.LISgt;2. 5, ( 5. 93 ±5. 21) ng/L vs. ( 6. 68 ±2. 76) ng/L, P gt; 0. 05] . The ET-1 level in the death group continued to increase, and higher than that in the survival group on the 5th day [ ( 7. 96 ±3. 30) ng/L vs.( 4. 36 ±3. 29) ng/L, P lt; 0. 05] . The ET-1 level was positively correlated with SIRS, SAPSⅡ and APACHEⅡ ( r = 0. 359, 0. 369 and 0. 426, respectively, P lt; 0. 05 ) , and negatively correlated with PaO2 /FiO2 and AaDO2 ( r = - 0. 286 and - 0. 300, respectively, P lt;0. 05) . Conclusion The measurementof serum ET-1 can help to evaluate the severity and prognosis of ALI/ARDS patients.
Objective To investigate the feasibility of collecting exhaled breath condensate ( EBC)fromartificially ventilated patients with modified EcoScreen condenser. Methods ①In vitro test with lung simulator: the modified EcoScreen condenser was connected to lung simulator and mechanically ventilated for 60 min through three different types of connected tube as follows: dry ventilator pipe disconnected to humidifier, connected to the unheated humidifier, and connected to heated humidifier.Meanwhile, the changes of the peak pressure of inspiration ( PI) and tidal volume ( VT ) were observed. The volume of condensate was measured at last. ②In vivo test from artificially ventilated patients: 10 patients were artificially ventilated and their EBCs were collected with the modified EcoScreen condenser through dry pipe disconnected to humidifier for 20 min. The changes of PI, VT , respiratory frequency( f) , heart rate( HR) , mean arterial blood pressure ( MAP) , and blood oxygen saturation ( SpO2 ) were observed. Results ①In vitro test with lung simulator: At the end of the ventilating through the dry pipe disconnected to humidifier for 60 min,2. 2 mL condensate wascollected. Neither the change of PI or VT nor the obstruction of the collecting tube by iced condensate were observed. The ventilating through dry pipe connected to unheated humidifier had to stop at 50 min as the obstruction of the collecting tube caused by ice. 5 mL condensate was collected. It was observed that VTdecreased and PI increased. After ventilation through dry pipe connected to heated humidifier for 60 min,10. 5 mL condensate was collected while PI slightly increased and VT decreased. ② In vivo test from artificially ventilated patients: After ventilation through dry pipe disconnected to humidifier for 20 min, 2 mL EBC was collected without significance changes in PI, VT, f, HR, MAP, and SpO2 . Conclusions The modified EcoScreen condenser can be favourably applied to artificially ventilated patients for collecting EBC.It is recommended to performfor 20 min through the pipe disconnected to humidifier to obtain sufficient EBC without condensate dilution and airway obstruction. It is warranted more attention to the clinical and mechanical monitoring in this procedure.
ObjectiveTo detect the concentration of 8-isoprostane (8-iso-PG) in exhaled breath condensate (EBC) of patients with or at risk for ARDS in ventilation, and investigate its clinical significance.MethodsFifty-five patients with or at risk for ARDS in ventilation admitted between February 2014 and June 2016 were recruited as an experimental group, and simultaneous 30 normal cases were recruited as a control group. Their EBC was collected with EcoScreen condenser. The EBC 8-iso-PG level of the patients between different grades of ARDS (mild, moderate, and sever) or at risk for ARDS was compared, and the correlation of EBC 8-iso-PG with the clinical indicators was analyzed.ResultsThe 8-iso-PG levels in EBC and serum of the patients with or at risk for ARDS in ventilation were higher than those in the control group [EBC: (44.83±11.58) ng/L vs. (19.47±4.06) ng/L; serum: (481.53±444.94) ng/L vs. (19.91±17.60) ng/L] (all P<0.05). The EBC 8-iso-PG of the patients with moderate ARDS (n=15) and severe ARDS (n=7) [(47.18±11.68) ng/L and (50.29±11.06) ng/L] was higher than those with mild ARDS (n=7) or at risk for ARDS (n=26) [(33.04±7.62) ng/L) and (37.17±11.08) ng/L] (all P<0.05). However EBC 8-iso-PG was not different between the patients with mild ARDS and those at risk for ARDS (P>0.05 ). The increased EBC 8-iso-PG could predict ARDS with an area under the receiver operating curve of 0.73. The EBC 8-iso-PG of the patients with or at risk for ARDS was correlated with lung injury score (r=0.418, P<0.01), PaO2/FiO2 (r=–0.378, P<0.05), chest radiograph scores (r=0.410, P<0.05), AaDO2 (r=0.368, P<0.05), and APACHEⅡ score (r=0.718, P<0.05).ConclusionEBC 8-iso-PG can reflect the oxidative stress in lung of ARDS patients in ventilation, and can contribute to the diagnosis and evaluation for moderate and severe ARDS.
Objective To observe the level of vascular endothelium growth factor A( VEGF-A) in exhaled breath condensate ( EBC) of patients with acute lung injury/acute respiratory distress syndrome ( ALI/ARDS) , and investigate its clinical significance. Methods EBC of 23 patients with ALI/ARDS by mechanical ventilation in intensive care unit ( ICU) were collected with improved EcoScreen condenser. EBC of 17 normal control subjects were collected with EcoScreen condensor. The level of VEGF-A was measured by ELISA in EBC and serum. The levels of VEGF-A in EBC of patients with different grades of lung injuries were compared, and the correlation was analyzed between the level of VEGF-A and clinical indicators. Results The level of VEGF-A in EBC was lower in the patients with ALI/ARDS than that of control subjects [ ( 49. 88 ±6. 32) ng/L vs. ( 56. 50 ±6. 323) ng/L, P lt;0. 01] , the level of VEGF-A was higher in the ALI patients than that of ARDS patients [ ( 53. 56 ±5. 56) ng/L vs. ( 45. 86 ±4. 45) ng/L, P lt;0. 01] ,and higher in the survival patients than that of the died patients [ ( 51. 92 ±6. 28) ng/L vs. ( 46. 05 ± 4. 58) ng/L, P lt;0. 05] . The level of VEGF-A in EBC was negatively correlated with lung injury score and A-aDO2 /PaO2 ( r = - 0. 426 and - 0. 510, respectively, P lt;0. 05) , and positively correlated with PaO2 /FiO2 and PaO2 ( r =0. 626 and 0. 655, respectively, P lt; 0. 05) . The level of VEGF-A in serum was not different between the ALI/ARDS patients and the control subjects, between the ALI and ARDS patients, or between the survival and the died patients ( all P gt;0. 05) . The level of VEGF-A in serumhad no correlation with lung injury score, A-aDO2 /PaO2 , PaO2 /FiO2 , or PaO2 ( all P gt;0. 05) . Conclusion The changes of VEGF-A in EBC of patients with ALI/ARDSmay serve as an indicator for severity and prognosis evaluation.