Objective To explore the effects of different humidification and heating strategies during non-invasive positive pressure ventilation( NIPPV) in patients with ALI/ARDS. Methods A total of 45 patients with ALI/ARDS were randomly divided into three groups to receive NIPPV with different humidification and heating strategies, ie. Group A ( humidification with a 370 Humidifier without heating) ,group B ( humidification with a 370 Humidifier along with a MR410 Heater) , and group C ( humidification and heating with aMR850 Humidifier, and a RT308 circuit heater) . The changes of air temperature, absolute humidity, relative humidity, sputum thickness and patient comfort were compared between the three groups. Sputum thickness was evaluated with AWSS scoring system. Results After humidification and heating, the air temperature, absolute humidity and AWSS score improved significantly in group B [ elevated from ( 23. 9 ±1. 0) ℃, (9.8 ±1. 3) mg/L and 2. 0 ±0. 7 respectively to ( 30. 3 ±1. 7) ℃, ( 31. 0 ±2. 3)mg/L and ( 3. 0 ±0. 9) respectively, P lt; 0. 001] and group C [ elevated from( 23. 8 ±1. 0) , ( 9. 8 ±1. 5)mg/L and ( 2. 1 ±0. 7) respectively to ( 34. 0 ±1. 1) ℃, ( 43.8 ±2. 5) mg /L and 3. 5 ±1. 0 respectively,P lt; 0. 001] . Air temperature and absolute humidity were significantly higher in group C than those in group B( P lt; 0. 001) . Of all the parameters, only absolute humidity showed a significant improvment in group A [ elevated from( 9. 9 ±1. 6) mg/L to ( 11. 9 ±0. 9) mg/L, P lt; 0. 001] . The degree of comfort in group C was significantly higher than that in group A and B [ 8. 0 ±1. 7 vs 5. 0 ±1. 2 and 3. 0 ±0. 4, respectively, P lt;0. 001] . In group A seven patients were switched to group C because of discomfort, four accepted NIPPV continuously, and two avoided invasive mechanical ventilation eventually. In group B three patients were switched to group C because of intolerance of too much condensed water in the breathing circuit, all of them accepted NIPPV continuously, and one avoided invasive mechanical ventilation eventually. Conclusions Compared with mere humidification or humidification with heating humidifier, humidification with heating humidifier and circuit heating during NIPPV can improve the absolute humidity, air temperature and patient comfort,meanwhile decreasing the sputumthickness of patients with ALI/ARDS.
Objective To investigate the role of angiotensin-II type 1 receptor ( AT1) antagonist in treatment of acute lung injury/acute respiratory distress syndrome ( ALI/ARDS) . Methods Animal model of ALI/ARDS was induced by cecal ligation and perforation ( CLP) . ALI/ARDS animals received a separate intraperitoneal injection of several concentrations( 5, 10, 15, 20, 25 mg/kg) of AT1 inhibitor losartan after CLP, then the changes of lung injury and 7-day survival were measured. Results Oxygenation index and lung wet to dry weight ratio ( W/D) showed an improving trend when losartan was administered at doses of 5 to 15 mg/kg in ALI/ARDS rats, but aggravated above the dose of 15 mg/kg. Losartan ( 15 mg/kg) treatment significantly alleviated pulmonary edema after CLP operation, and decreased serumlevels of TNF-α, IL-6, andIL-1β [ TNF-α: ( 554. 1 ±62. 7 ) pg/mL vs. ( 759. 2 ±21. 5 ) pg/mL, P lt; 0. 01; IL-6: ( 1227. 3 ±130. 0) pg/mL vs. ( 2670. 4 ±174. 1) pg/mL, P lt; 0. 01; IL-1β: ( 444. 0 ±38. 6) pg/mL vs. ( 486. 6 ±61. 7)pg/mL, P lt; 0. 05] . 7-day survival rate also increased in losartan treatment group at a dose of 15 mg/kg( 6. 7% vs. 0 ) . Conclusions The AT1 inhibitor, losartan, can significantly prevent lung injury in ALI/ARDS after CLP, and improve the 7-day survival rate.
Objective To review the effects of pulmonary surfactant in adult patients with acute lung injury ( ALI) /acute respiratory distress syndrome ( ARDS) . Methods Randomized controlled trials ( RCTs) were recruited from PubMed ( 1966.1-2011.3) , ISI Web of Knowledge ( all the years) and Wanfang Database ( 1982-2011) . Related published data and attached references were hand searched. All the RCTs about pulmonary surfactant for the adult patients with ALI/ARDS were included, then a meta-analysis was performed. Results Eight eligible trials were enrolled. Pooled analysis showed that treatment with pulmonary surfactant was not associated with reduction in 28 or 30-day mortality compared with the control group [ OR 1.05, 95% CI ( 0.90, 1.22 ) , P = 0.55] , neither did subgroup analysis in the pneumoia/ aspiration, sepsis, and trauma/ surgery induced ALI/ARDS patients. Three RCTs showed the oxygenation was significantly improved in adult ALI/ARDS patients receiving pulmonary surfactant compared with the control group( Plt;0.05) . Shorter mechanical ventilation days was shown in the ALI/ARDS patients receiving pulmonary surfactant in one RCT(Plt;0.05) . Conclusions Meta-analysis showed pulmonary surfactant did not reduce the 28 or 30-day mortality of adult patients with ALI/ARDS, however, improved the oxygenation. Pulmonary surfactant can be considered a therapy in ALI/ARDS.
Objective To investigate the concentration of 8-isoprostaglandin ( 8-iso-PG) in exhaled breath condensate ( EBC) of patients with acute lung injury/acute respiratory distress syndrome ( ALI/ ARDS) , and evaluate its clinical significance. Methods Thirty-one ALI/ARDS patients who received mechanical ventilation were recruited as an experimental group, and EBC was collected with improved EcoScreen condenser, while thirty normal subjects were recruited as a control group. The 8-iso-PG level in EBC was analyzed by ELISA. The ALI/ARDS patients were subdivided into a continuous ALI group ( n=10) , a continuous ARDS group ( n=9) , a worsening group ( n=6) , and a remission group ( n=6) by state of illness on 1st day and 5th day. The 8-iso-PG level in EBC of the ALI/ARDS patients with different severity and different prognosis were compared, and the correlation were analyzed between the 8-iso-PG level and clinical indicators. Results The 8-iso-PG levels in EBC of the ALI/ARDS patients on 1st day and 5th day were higher than those in the control subjects respectively [ ( 45.53 ±14.37) ng/L and ( 45.31 ±12.42) ng/L vs. ( 19.47 ±4.06) ng/L, Plt;0.001] . The 8-iso-PG level was higher in the worsening group than the remission group, higher in the continuous ARDS group than the continuous ALI group, and higher in the nonsurvival group than the survival group ( Plt;0.05) . The 8-iso-PG level in EBC was positively correlated with white blood cell count in peripheral blood, lung injury score, X-ray score, AaDO2 /PaO2 , AaDO2 , VT , VE and MEWS score, and negatively correlated with PaO2 /PAO2 and PaO2 /FiO2 . Conclusion The 8-iso-PG level in EBC of ALI/ARDS patients has reference value for judging severity and prognosis of ALI/ARDS.