Document Detail

Mechanisms of blood flow during pneumatic vest cardiopulmonary resuscitation.
MedLine Citation:
PMID:  2010405     Owner:  NLM     Status:  MEDLINE    
Mechanisms of blood flow during cardiopulmonary resuscitation (CPR) were studied in a canine model with implanted mitral and aortic flow probes and by use of cineangiography. Intrathoracic pressure (ITP) fluctuations were induced by a circumferential pneumatic vest, with and without simultaneous ventilation, and by use of positive-pressure ventilation alone. Vascular volume and compression rate were altered with each CPR mode. Antegrade mitral flow was interpreted as left ventricular (LV) inflow, and antegrade aortic flow was interpreted as LV outflow. The pneumatic vest was expected to elevate ITP uniformly and thus produce simultaneous LV inflow and LV outflow throughout compression. This pattern, the passive conduit of "thoracic pump" physiology, was unequivocally demonstrated only during ITP elevation with positive-pressure ventilation alone at slow rates. During vest CPR, LV outflow started promptly with the onset of compression, whereas LV inflow was delayed. At compression rates of 50 times/min and normal vascular filling pressures, the delay was sufficiently long that all LV filling occurred with release of compression. This is the pattern that would be expected with direct LV compression or "cardiac pump" physiology. During the early part of the compression phase, catheter tip transducer LV and left atrial pressure measurements demonstrated gradients necessitating mitral valve closure, while cineangiography showed dye droplets moving from the large pulmonary veins retrograde to the small pulmonary veins. When the compression rate was reduced and/or when intravascular pressures were raised with volume infusion, LV inflow was observed at some point during the compressive phase. Thus, under these conditions, features of both thoracic pump and cardiac pump physiology occurred within the same compression. Our findings are not explained by the conventional conceptions of either thoracic pump or cardiac compression CPR mechanisms alone.
C Beattie; A D Guerci; T Hall; A M Borkon; W Baumgartner; R S Stuart; J Peters; H Halperin; J L Robotham
Related Documents :
15693775 - Effects of alcohol septal ablation for hypertrophic obstructive cardiomyopathy on doppl...
16461055 - Correlation of echo-doppler optimization of atrioventricular delay in cardiac resynchro...
11376315 - Relationship of impaired glucose tolerance to left ventricular structure and function: ...
20970305 - Systolic and diastolic myocardial mechanics in patients with cardiac disease and preser...
22523635 - Large amplitude fluxional behaviour of elemental calcium under high pressure.
24221295 - Comparative spray drift studies of aerial and ground applications 1983-1985.
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Journal of applied physiology (Bethesda, Md. : 1985)     Volume:  70     ISSN:  8750-7587     ISO Abbreviation:  J. Appl. Physiol.     Publication Date:  1991 Jan 
Date Detail:
Created Date:  1991-05-07     Completed Date:  1991-05-07     Revised Date:  2013-09-26    
Medline Journal Info:
Nlm Unique ID:  8502536     Medline TA:  J Appl Physiol (1985)     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  454-65     Citation Subset:  IM    
Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Medical Institutions, Baltimore, Maryland 21205.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Blood Pressure / physiology
Coronary Circulation / physiology
Gravity Suits
Heart Arrest / physiopathology,  therapy
Hemodynamics / physiology*
Lung Volume Measurements
Resuscitation* / instrumentation,  methods
Grant Support

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Influence of lung volume and left atrial pressure on reverse pulmonary venous blood flow.
Next Document:  Synthesis of 70K stress protein by human leukocytes: effect of exercise in the heat.