Journal of Applied Physiology AJP: Endocrinology and Metabolism
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

J Appl Physiol (November 23, 2001). doi:10.1152/japplphysiol.00487.2001
This Article
Right arrow Full Text (PDF) Free
Right arrow All Versions of this Article:
92/3/1223    most recent
00487.2001v1
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Van den Berg, P. C
Right arrow Articles by Pinsky, M. R
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Van den Berg, P. C
Right arrow Articles by Pinsky, M. R

Articles in PresS, published online ahead of print November 23, 2001
J Appl Physiol, 10.1152/jap.00487.2001
Submitted on May 18, 2001
Accepted on November 5, 2001

The effect of positive-pressure inspiration on venous return in volume loaded post-operative cardiac surgical patients

Paul C Van den Berg1*, Jos R Jansen1, and Michael R Pinsky2

1 Intensive Care, Leiden University Medical Center, Leiden, Netherlands
2 Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA, USA

* To whom correspondence should be addressed. E-mail: JRCJansen{at}lumc.nl.

The hemodynamic effects of increases in airway pressure (Paw) are related in part to Paw-induced increases in right atrial pressure (Pra), the downstream pressure for venous return, thus decreasing the pressure gradient for venous return. However, numerous animal and clinical studies have shown that venous return is often sustained during ventilation with positive end-expiratory pressure (PEEP). Potentially, PEEP-induced diaphragmatic descent increase abdominal pressure (Pabd). We hypothesized that an increase in Paw induced by PEEP would minimally alter venous return because the associated increase in Pra would be partially offset by a concomitant increase in Pabd. Thus, we studied the acute effects of sustained graded increases of Paw on Pra, Pabd and cardiac output by application of inspiratory hold maneuvers in sedated and paralyzed humans. Forty-two patients were studied in the intensive care unit following coronary artery bypass surgery during hemodynamically stable fluid-resuscitated conditions. Paw was progressively increased in steps of 2 to 4 cm H2O from 0 to 20 cm H2O in sequential 25-second inspiratory hold maneuvers. Right ventricular (RV) output (COtd) and RV ejection fraction (EFrv) were measured at 5 seconds into the inspiratory hold maneuver by the thermodilution technique. Whereas RV end-diastolic volume and stroke volume were calculated from the COtd, EFrv and heart rate data. Pra was measured from the pulmonary artery catheter. Pabd was estimated as bladder pressure. We found that although increasing Paw progressively increased Pra, neither COtd or RV end-diastolic volume changed. The ratio of increase in ({Delta}) Paw to {Delta}Pra was 0.32 ± 0.20. The ratio of {Delta}Pra to {Delta}COtd was 0.05 ± 0.15 l/min/mm Hg. However, Pabd increased, such that the ratio of {Delta}Pra to {Delta}Pabd was 0.73 ± 0.36, meaning that most of the increase in Pra was reflected in increases in Pabd. We conclude that in the hemodynamically stable fluid-resuscitated post-operative surgical patients inspiratory hold maneuvers with increases in Paw of up to 20 cm H2O have minimal effects on cardiac output, primarily because of an in-phase associated pressurization of the abdominal compartment associated with compression of the liver and by squeezing of the lungs.




This article has been cited by other articles:


Home page
 ChestHome page
M. R. Pinsky
Hemodynamic Evaluation and Monitoring in the ICU
Chest, December 1, 2007; 132(6): 2020 - 2029.
[Abstract] [Full Text] [PDF]

Home page
 Anesth. Analg.Home page
M. F. Haney, G. Johansson, S. Haggmark, B. Biber, M. F. Haney, G. Johansson, S. Haggmark, and B. Biber
Myocardial Systolic Function Increases During Positive Pressure Lung Inflation
Anesth. Analg., November 1, 2005; 101(5): 1269 - 1274.
[Abstract] [Full Text] [PDF]

Home page
 ChestHome page
M. R. Pinsky
Cardiovascular Issues in Respiratory Care
Chest, November 1, 2005; 128(5_suppl_2): 592S - 597S.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
S. L. Munns, L. K. Hartzler, A. F. Bennett, and J. W. Hicks
Terrestrial locomotion does not constrain venous return in the American alligator, Alligator mississippiensis
J. Exp. Biol., September 1, 2005; 208(17): 3331 - 3339.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
H. E. Cooper, T. H. Clutton-Brock, and M. J. Parkes
Contribution of the respiratory rhythm to sinus arrhythmia in normal unanesthetized subjects during positive-pressure mechanical hyperventilation
Am J Physiol Heart Circ Physiol, January 1, 2004; 286(1): H402 - H411.
[Abstract] [Full Text] [PDF]

Home page
 RadiologyHome page
C. Wittram and C. B. Henk
Pulmonary Artery Enhancement at CT Pulmonary Angiography [letter] * Drs Henk and Grampp respond:
Radiology, December 1, 2003; 229(3): 932 - 933.
[Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 2009 by the American Physiological Society.