RT Book, Section
A1 Weber, Karl T.
A1 Newman, Kevin P.
A2 Grippi, Michael A.
A2 Elias, Jack A.
A2 Fishman, Jay A.
A2 Kotloff, Robert M.
A2 Pack, Allan I.
A2 Senior, Robert M.
A2 Siegel, Mark D.
SR Print(0)
ID 1122358097
T1 Principles and Applications of Cardiopulmonary Exercise Testing
T2 Fishman's Pulmonary Diseases and Disorders, 5e
YR 2015
FD 2015
PB McGraw-Hill Education
PP New York, NY
SN 978-0-07-179672-9
LK accessmedicine.mhmedical.com/content.aspx?aid=1122358097
RD 2024/04/25
AB Cardiopulmonary  exercise  (CPX)  testing  draws  on  the  recognition  that  the  thorax  represents  a  metabolic  gas  transport  unit,  the  function  of  whose  requisite  components  –  diaphragm,  heart,  lungs,  rib  cage,  and  corresponding  skeletal  muscles  –  is  to  transport  O2  to  and  CO2  from  metabolizing  tissues.  Unit  O2  and  CO2  transport  must  adjust  to  physiological  and  pathophysiological  stresses  that  augment  the  body's  consumption  of  oxygen  (V̇O2)  and  carbon  dioxide  production  (V̇CO2).  During  strenuous  levels  of  muscular  work,  for  example,  V̇O2  may  rise  eightfold,  accompanied  by  increased  V̇CO2.  Cardiovascular  or  ventilatory  disease  can  disrupt  the  unit's  functional  integrity.  With  severe  disease,  an  abnormality  in  respiratory  gas  transport  may  be  apparent  at  rest,  when  the  body's  O2  requirements  are  modest.  Resting  function  is  preserved  with  less  severe  expressions  of  disease,  but  abnormal  respiratory  gas  transport  becomes  apparent  when  the  unit  is  stressed  by  an  elevation  in  V̇O2.