Effect of Recruitment and Body Positioning on Lung Volume and Oxygenation in Acute Lung Injury Model

The mechanism of oxygenation improvement after recruitment manoeuvres or prone positioning in acute lung injury or acute respiratory distress syndrome is still unclear. We tried to determine the mechanism responsible for the effects of recruitment manoeuvres or prone positioning on lung aeration using a whole lung computed tomography scan in an oleic acid induced acute lung injury canine model. Twelve adult mongrel dogs were allocated into either the supine group (n=6) or the prone group (n = 6). After the establishment of acute lung injury, three recruitment manoeuvres were performed at one-hour intervals. Haemodynamic and ventilatory variables, arterial blood gas analyses and CT scans of the whole lung were obtained 90 minutes after oleic acid injection and five minutes before and after each recruitment manoeuvre. Recruitment manoeuvres in the supine position improved oxygenation (P=0.025) that correlated with increase of the poorly- and well-aerated dorsal (dependent) lung volume (r=0.436, P=0.016). Prone positioning increased oxygenation (P=0.004) that also correlated with increase of the poorly- and well-aerated dorsal (nondependent) lung volume (r=0.787, P <0.001). However, the recruitment manoeuvre in the prone position had no effect on oxygenation despite an increase in ventral (dependent) lung volume. The increase in PO2 after recruitment manoeuvres in the supine position or after prone positioning is related to the increase of the poorly- and well-aerated dorsal lung.

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Eicosanoid balance and perfusion redistribution of oleic acid-induced acute lung injury

Journal of Applied Physiology ◽

10.1152/jappl.1992.73.5.2126 ◽

1992 ◽

Vol 73 (5) ◽

pp. 2126-2134 ◽

Cited By ~ 20

Author(s):

A. H. Stephenson ◽

A. J. Lonigro ◽

S. W. Holmberg ◽

D. P. Schuster

Keyword(s):

Acute Lung Injury ◽

Oleic Acid ◽

Lung Injury ◽

Water Concentration ◽

Dependent Lung ◽

Lung Water ◽

Tissue Concentrations ◽

Tissue Samples ◽

Positron Emission ◽

Regional Lung

We have proposed that endogenous prostacyclin opposes the vasoconstriction responsible for redistribution of regional pulmonary blood flow (rPBF) away from areas of increased regional lung water concentration (rLWC) in canine oleic acid- (OA) induced acute lung injury (D. P. Schuster and J. Haller. J. Appl. Physiol. 69: 353–361, 1990). To test this hypothesis, we related regional lung tissue concentrations of 6-ketoprostaglandin (PG) F1 alpha and thromboxane (Tx) B2 in tissue samples obtained 2.5 h after administration of OA (0.08 ml/kg iv) to rPBF and rLWC measured by positron emission tomography. After OA only (n = 16), rLWC increased in dependent lung regions. Some animals responded to increased rLWC by redistribution of rPBF away from the most edematous regions (OA-R, n = 6), whereas others did not (OA-NR, n = 10). In another six animals, meclofenamate was administered after OA (OA-meclo). After OA, tissue concentrations of 6-keto-PGF1 alpha were greater than TxB2 in all groups, but concentrations of 6-keto-PGF1 alpha were not different between OA-R and OA-NR animals. TxB2 was increased in the dependent regions of animals in both OA-R and OA-NR groups compared with controls (no OA, n = 4, P < 0.05). The tissue TxB2/6-keto-PGF1 alpha ratio was smaller in controls and OA-NR in which no perfusion redistribution occurred than in OA-R and OA-meclo in which it did occur. This TxB2/6-keto-PGF1 alpha ratio correlated significantly with the magnitude of perfusion redistribution.(ABSTRACT TRUNCATED AT 250 WORDS)

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Peripheral Leukocytapheresis Attenuates Acute Lung Injury Induced by LipopolysaccharideIn Vivo

Mediators of Inflammation ◽

10.1155/2012/694635 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9

Author(s):

Zhi-Gao He ◽

Jian Huang ◽

Shun-Gang Zhou ◽

Jing He ◽

Fang-Xiang Chen ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Distress Syndrome ◽

Serum Levels ◽

Partial Removal ◽

Arterial Blood Gas ◽

The Past ◽

Arterial Blood ◽

Lung Injuries ◽

Elastase Level

The mortality of acute lung injury and acute respiratory distress syndrome (ALI/ARDS) remains high and efforts for prevention and treatments have shown little improvement over the past decades. The present study investigated the efficacy and mechanism of leukocytapheresis (LCAP) to partially eliminate peripheral neutrophils and attenuate lipopolysaccharide (LPS)-induced lung injury in dogs. A total of 24 healthy male mongrel dogs were enrolled and randomly divided into LPS, LCAP and LCAP-sham groups. All animals were injected with LPS to induce endotoxemia. The serum levels of leucocytes, neutrophil elastase, arterial blood gas, nuclear factor-kappa B (NF-κB) subunit p65 in lung tissues were measured. The histopathology and parenchyma apoptosis of lung tissues were examined. We found that 7, 3, and 7 animals in the LPS, LCAP, and sham-LCAP groups, respectively, developed ALI 36 h after LPS infusion. The levels of NF-κB p65 in lung tissue, neutrophils and elastase in blood, decreased significantly following LCAP. LCAP also alleviated apoptosis, and NF-κB p65 in lung tissues. Collectively, our results show that partial removal of leucocytes from peripheral blood decreases elastase level in serum. This, in turn, attenuates lung injuries and may potentially decrease the incidence of ALI.

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Bone Marrow Mesenchymal Stem Cells Ameliorates Seawater-Exposure-Induced Acute Lung Injury by Inhibiting Autophagy in Lung Tissue

Pathology Research International ◽

10.1155/2014/104962 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Qiu-ping Liu ◽

Dang-xia Zhou ◽

Li Sun ◽

Luo Ling ◽

Chang-gui Wu ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mesenchymal Stem Cells ◽

Acute Lung Injury ◽

Lung Injury ◽

Blood Gas ◽

Lung Weight ◽

Arterial Blood Gas ◽

Arterial Blood ◽

Marrow Mesenchymal Stem Cells

Seawater drowning can lead to acute lung injury (ALI). Several studies have shown that bone marrow mesenchymal stem cells (BMSC) treatment could attenuate ALI. However, the mechanisms underlying this phenomenon still remain elusive. Therefore, this study aimed to investigate whether BMSC treatment can ameliorate seawater-induced ALI and its underlying mechanisms in a rat model. In this study, arterial blood gas, lung weight coefficient, and TNF-α, and IL-8 in bronchoalveolar lavage fluid (BALF), as well as histopathology examination, were used to detect the lung injury of seawater exposure. Moreover, western blot and RT-PCR were used to explore autophagy in lung tissues. The results demonstrated that seawater exposure induced ALI including impaired arterial blood gas, pulmonary edema, histopathologic changes, and inflammatory response in lung tissues. What is more, these changes were partly ameliorated by BMSC treatment through inhibition of autophagy in lung tissues. The application of BMSC may be a potential effective treatment for seawater-induced ALI.

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Detection of porcine oleic acid-induced acute lung injury using pulmonary acoustics

Journal of Applied Physiology ◽

10.1152/japplphysiol.01238.2001 ◽

2002 ◽

Vol 93 (1) ◽

pp. 51-57 ◽

Cited By ~ 18

Author(s):

Jukka Räsänen ◽

Noam Gavriely

Keyword(s):

Acute Lung Injury ◽

Oleic Acid ◽

Lung Injury ◽

Respiratory System ◽

Dynamic Compliance ◽

Venous Admixture ◽

Dependent Lung ◽

Broadband Sound ◽

Dynamic Respiratory System Compliance ◽

Severe Lung

To evaluate the utility of monitoring the sound-filtering characteristics of the respiratory system in the assessment of acute lung injury (ALI), we injected a multifrequency broadband sound signal into the airway of five anesthetized, intubated pigs, while recording transmitted sound over the trachea and on the chest wall. Oleic acid injections effected a severe lung injury predominantly in the dependent lung regions, increasing venous admixture from 6 ± 1 to 54 ± 8% ( P < 0.05) and reducing dynamic respiratory system compliance from 19 ± 0 to 12 ± 2 ml/cmH2O ( P < 0.05). A two- to fivefold increase in sound transfer function amplitude was seen in the dependent ( P < 0.05) and lateral ( P < 0.05) lung regions; no change occurred in the nondependent areas. High within-subject correlations were found between the changes in dependent lung sound transmission and venous admixture ( r = 0.82 ± 0.07; range 0.74–0.90) and dynamic compliance ( r = −0.87 ± 0.05; −0.80 to −0.93). Our results indicate that the acoustic changes associated with oleic acid-induced lung injury allow monitoring of its severity and distribution.

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Extravascular Lung Water and Acute Lung Injury

Cardiology Research and Practice ◽

10.1155/2012/407035 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 11

Author(s):

Ritesh Maharaj

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Extravascular Lung Water ◽

Response To Treatment ◽

Dilution Method ◽

Lung Water ◽

Arterial Blood Gas ◽

Arterial Blood ◽

Chest Auscultation

Acute lung injury carries a high burden of morbidity and mortality and is characterised by nonhydrostatic pulmonary oedema. The aim of this paper is to highlight the role of accurate quantification of extravascular lung water in diagnosis, management, and prognosis in “acute lung injury” and “acute respiratory distress syndrome”. Several studies have verified the accuracy of both the single and the double transpulmonary thermal indicator techniques. Both experimental and clinical studies were searched in PUBMED using the term “extravascular lung water” and “acute lung injury”. Extravascular lung water measurement offers information not otherwise available by other methods such as chest radiography, arterial blood gas, and chest auscultation at the bedside. Recent data have highlighted the role of extravascular lung water in response to treatment to guide fluid therapy and ventilator strategies. The quantification of extravascular lung water may predict mortality and multiorgan dysfunction. The limitations of the dilution method are also discussed.

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Study on the Efficacy and Safety of Ambroxol Combined with Methylprednisolone in Patients with Acute Lung Injury

BioMed Research International ◽

10.1155/2021/5771101 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Weiwei Su ◽

Qinglian Dong ◽

Fangfang Jiao

Keyword(s):

Acute Lung Injury ◽

Treatment Group ◽

Lung Injury ◽

Oxygen Partial Pressure ◽

Partial Pressure ◽

Combined Treatment ◽

Oxygenation Index ◽

Arterial Blood Gas ◽

Arterial Blood ◽

Tnf Α

Background. There is no better treatment method towards paraquat-induced acute lung injury (ALI) at present. Ambroxol combined with methylprednisolone exhibits a significant improvement effect on ALI treatment, whereas their mechanism in ALI is still unclear. Methods. 64 patients with ALI caused by paraquat poisoning brought to our hospital from January 2015 to January 2018 were selected. They were separated into a combined treatment group (CTG) and a routine treatment group (RTG) on the basis of different treatment methods. The survival of patients was observed after 7 days of treatment. Arterial blood gas, oxygen partial pressure (PaO2), partial pressure of carbon dioxide (PaCO2), oxygenation index (PaO2/FiO2), patient’s spontaneous respiratory rate (RR), tidal volume (VT), and positive end-expiratory pressure (PEEP) were observed before and after treatment for 7 days. Interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were analyzed. The differences of indexes between the dead patients and the survivors were observed, and the potential predictive value of death was analyzed. Results. After treatment, the indexes of patients were significantly improved in both groups compared with those before therapy. Further comparison showed that the improvement of PaO2, PaCO2, and PaO2/FiO2 in CTG was obviously higher than that in RTG ( p < 0.05 ). The improvement of RR, PEEP, and VT in CTG was obviously higher than that in RTG ( p < 0.05 ). The decreased degree of IL-6 and TNF-α in CTG was higher than that in RTG ( p < 0.05 ). The 7-day mortality rate of 64 patients was 39.06%, and there was no obvious difference in the 7-day survival rate in both groups ( p = 0.649 ). IL-6 and TNF-α were expected to be potential prediction indexes of paraquat-induced ALI. Conclusion. Ambroxol combined with methylprednisolone significantly improved the oxygen partial pressure and oxygenation index of patients with paraquat-induced ALI and inhibited the inflammatory response of patients.

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