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Research Article Free access | 10.1172/JCI105655
Department of Surgery, St. Vincent's Hospital and Medical Center of New York and New York University School of Medicine, New York
Department of Medicine, St. Vincent's Hospital and Medical Center of New York and New York University School of Medicine, New York
‡Address requests for reprints to Dr. Stanley Giannelli, Jr., 153 West 11 Street, New York 10011.
*Received for publication 27 December 1966 and in revised form 15 June 1967.
This work was supported by the Health Research Council of the City of New York under contract No. U 1431, the National Institutes of Health, grants No. HE 08636 and No. HE 10781-01, and The Council for Tobacco Research-U.S.A.
This material was presented in part at the annual meeting of the American Federation for Clinical Research, Atlantic City, N. J., 1 May 1966.
Find articles by Giannelli, S. in: JCI | PubMed | Google Scholar
Department of Surgery, St. Vincent's Hospital and Medical Center of New York and New York University School of Medicine, New York
Department of Medicine, St. Vincent's Hospital and Medical Center of New York and New York University School of Medicine, New York
‡Address requests for reprints to Dr. Stanley Giannelli, Jr., 153 West 11 Street, New York 10011.
*Received for publication 27 December 1966 and in revised form 15 June 1967.
This work was supported by the Health Research Council of the City of New York under contract No. U 1431, the National Institutes of Health, grants No. HE 08636 and No. HE 10781-01, and The Council for Tobacco Research-U.S.A.
This material was presented in part at the annual meeting of the American Federation for Clinical Research, Atlantic City, N. J., 1 May 1966.
Find articles by Ayres, S. in: JCI | PubMed | Google Scholar
Department of Surgery, St. Vincent's Hospital and Medical Center of New York and New York University School of Medicine, New York
Department of Medicine, St. Vincent's Hospital and Medical Center of New York and New York University School of Medicine, New York
‡Address requests for reprints to Dr. Stanley Giannelli, Jr., 153 West 11 Street, New York 10011.
*Received for publication 27 December 1966 and in revised form 15 June 1967.
This work was supported by the Health Research Council of the City of New York under contract No. U 1431, the National Institutes of Health, grants No. HE 08636 and No. HE 10781-01, and The Council for Tobacco Research-U.S.A.
This material was presented in part at the annual meeting of the American Federation for Clinical Research, Atlantic City, N. J., 1 May 1966.
Find articles by Buehler, M. in: JCI | PubMed | Google Scholar
Published October 1, 1967 - More info
Airway pressure was continuously recorded in an isolated horizontally mounted canine heart-lung preparation during abrupt, stepwise 100-200 ml inflations to 20-25 cm water pressure, and subsequent deflations. With each change in volume there was a steep rise or fall in pressure, followed by stress relaxation to a static equilibrium airway pressure. Comparison was made between the nonperfused state and during perfusion with whole blood at 100 ml/kg dog wt per min, and left atrial pressure of 10 mm Hg. Pressure tracings were similar during deflation in the perfused and the nonperfused lung. During inflation, in the middle range of lung inflation volumes, the peak inflation and equilibrium airway pressures were greater in the nonperfused state; maximum difference of static pressures in nine preparations averaged 146% of perfused values and the average stress relaxation difference from eight of these was 276%. Lung distensibility was the same with packed red cells or plasma perfusates and was not changed by varying the perfusion rate up to 220 ml/kg per min. During cyclic ventilation, dynamic compliance was similarly greater in the perfused than in the nonperfused state in the middle range of inflation volumes. Static distention of the vascular bed produced similar results with progressive improvement in distensibility in mid-inflation range up to a hydrostatic pressure of 15 cm blood. These data suggest that the distended pulmonary vascular bed provides structural airway support which facilitates entry of gas into the terminal respiratory units at diminished pressure.