Lungs mechanics

Utell, M. J. (1985). Effects of inhaled acid aerosols on lung mechanics an analysis of human exposure studies. Environmental Health Perspect. 63, 39-44. 

Six male Wistar rats inhaled HCN at 55 ppm for 30 min (Bhattacharya et al. 1984). HCN was generated by reaction of KCN with sulfuric acid and circulated through the chamber at the rate of 1 L/min. The rats were fitted with a lung mechanics analyzer (Buxco Electronic Inc.), and changes in air flow, transthoracic pressure, tidal volume, compliance, resistance, respiratory rate, and minute volume were determined every 10 min. Animals were sacrificed immediately following the exposure, and lungs were excised and analyzed for phospholipids (surfactant). 

Kroll F, Karlsson JA, Nilsson E, Persson CG, Ryrfeldt A (1986) Lung mechanics of the guinea-pig isolated perfused lung. Acta Physiol Scand 128 1-8. 

Urmey W, Scharf S, Song P, et al. 1980. Effects of interstitial fluid on lung mechanics in the rat. Federation of American Societies for Experimental Biology 64th Annual Meeting Anahiem, California. 

M.A. Kandler, K. von der Hardt, E. Schoof, J. Dotsch, W. Rascher, Persistent improvement of gas exchange and lung mechanics by aerosolized perfluorocarbon. Am. J. Resp. Crit. Care Med. 164 (2001) 31-35. 

Guinea pig Inhalation 0,13,1.01,5.72 12 mo Pulmonary function measurements indicated no adverse effects on lung mechanics. NOAEL 5.72 Alarie et al. 1970... 

AS can be studied in human or animal lung extracts as well as in the amniotic fluid (AF) where AS molecules are present [2,4-6]. Along with the biochemical, cytochemical and other techniques of AS investigation, very useful information can be derived from the model studies of lipid and protein/lipid monolayers at liquid substrates. These models provide important data about lung mechanics [e.g. 7-11]. 

Kumar, P., Vijayaraghavan, R., Pant, S.C., Sachan, A.S., Malhotra, R.C. (1995). Effect of inhaled aerosol of 1-chloroacetophenone (CN) and dibenz (b,f)-l,4-oxazepine (CR) on lung mechanics and pulmonary surfactants inrats. Plum. Exp. Toxicol. 14 404-9. 

Wheeler, A.P., Jesmok, G. and Brigham, K.L. (1990). Tumor necrosis fiictor s efferts on lung mechanics, gas exchange and airway reactivity in sheep. J. Appl. Physiol. 68, 2542-2549. 

Markers of physiological effects can be useful in identifying early changes in respiratory functions of the lung due to inhaled material. Biomarkers are available to measure lung mechanical properties, ventilation, expiratory flow, intrapulmonary gas distribution, alveolar-capillary gas exchange, and perfusion. Such measurements have been used to test the effects of exposure to an array of inhaled toxicants. These assays can reveal functional manifestation of structural changes in the respiratory system, whether... 

Matsumoto S (1997) The changes in pulmonary C-fiber activity and lung mechanics induced by vagal stimulation in rabbits. Life Sci 61 2189-2195... 

Fust A, LeBellego F, lozzo RV, Roughley PJ, Ludwig MS. Alterations in lung mechanics in decorin-deficient mice. Am J Physiol Lung Cell Mol Physiol 2005 288 L159-L166. 

Snapper, J.R., Hutchinson, A.A., Ogletree, M.L. and Brigham, K.L. (1983). Effects of cyclooxygenase inhibitors on the alterations in lung mechanics caused by endotoxemia in the unanesthetized sheep. ]. Clin. Invest., 72, 63-76... 

Greenough A, Loftus BG, Pool J, Price JF. Response to bronchodilators assessed by lung mechanics. Arch Dis Child 1986 61 1020-1023. 

De Troyer A, Yernault JC, Rodenstein D. Effects of vagal blockade on lung mechanics in normal man. J Appl Physiol 1979 46 217-226. 

FIGURE 10.21 Simultaneous registration of (1) heart mechanical pumping activity, (2) heart electrical activity, and (3) lung mechanical ventilation, using only two electrodes. (From Patterson R. 1995. The Biomedical Engineering Handbook. Boca Raton, FL, CRC Press, 3rd edition, pp. 1223-1230.)... 

Supplemental studies including blood gas analysis, end-tidal CO2 measurements, or responses to CO2 gas and NaCN can be conducted to gain mechanistic insight after the ventilatory and lung mechanical findings have been evaluated. In general, these would be conducted as separate studies. 

As shown from measurements in airway models or theories using modifications of the friction coefficients, the vast majority of the pressure drop across the entire lung occurs within the large airways, say 0 n 8. I us clinical evaluation of total airway resistance can miss diseases of the small airways whose diameters are less than 2 mm, the so-called silent zone of the network. Pressure drop measurements and models are also important for the design of ventilators and other respiratory assist or therapeutic devices that interface with lung mechanics. 

Bradvik 1, Wollmer P, Blom-Bulow B, et al. Lung mechanics and gas exchange during exercise in pulmonary sarcoidosis. Chest 1991 99(3) 572-578. 

The risk of VILI is less when lung mechanics are near normal and regional overdistention is less likely to occur. More generous VTs may be used to improve comfort, maintain recruitment, and prevent atelectasis. Maximal distending pressures should be kept as low as possible. The PAOplateau should be <30 cmH20. Low levels of PEEP may prevent atelectasis, as patients are often supine and incapable of secretion clearance or spontaneous sigh breaths. 

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