[Comparison of four different methods for respiratory determination of the anaerobic threshold in normal people, and heart- and lung patients].
We analyzed 128 cardiopulmonary exercise tests (CPX), performed in normal subjects (n = 31), in patients with coronary artery disease (n = 41), with chronic heart failure before (n = 14) and after (n = 14) application of oral PDE-inhibitors and in patients with HIV-infection on a bicycle-ergometer in semi-supine position using a ramp-program (dependent on study-population with 15, 20 or 35 Watt/min increases) with respect to the ability to determine the respiratory anaerobic threshold non-invasively, using the main criteria described by Wasserman et al.: the V-slope-method according to Beaver, the increase of the ventilatory equivalent for O2 (VE/VO2), the increase of the end-tidal PO2 (PETO2) and the increase of the respiratory quotient (RQ) during exercise. In the different study-populations we calculated the detection rates of the AT for each criteria separately. The typical changes in the end-tidal PO2 (124/128 = 96.9%) and the V-slope-method (119/128 = 92.9%) were the most reliable parameters to detect the anaerobic threshold. The characteristic changes of the ventilatory equivalent for O2 (VE/VO2) and of the respiratory quotient (RQ) we found in 100/128 (= 78.1%) and in 107/128 (= 83.6%) of the tests respectively. 86/128 tests (67.2%) showed typical changes in all four mentioned criteria. In another 24/128 tests (19.8%) three of four criteria were fulfilled. Therefore, our investigations showed that in 110/128 cases (85.9%) the AT could be determined by typical changes by means of at least three of the four described parameters. In 15/128 (11.7%) tests only two of four criteria were fulfilled.(ABSTRACT TRUNCATED AT 250 WORDS)
Gitt
A K
AK
Klinik III für Innere Medizin, Kardiologie, Universität zu Köln.
Winter
U J
UJ
Fritsch
J
J
Pothoff
G
G
Sedlak
M
M
Ehmanns
S
S
Ostmann
H
H
Hilger
H H
HH
D015308:Anaerobic Threshold / Q000187:drug effects / Q000502:physiology*; D002245:Carbon Dioxide / Q000502:physiology; D003327:Coronary Disease / Q000188:drug therapy / Q000503:physiopathology*; D005080:Exercise Test / Q000187:drug effects / Q000295:instrumentation*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000503:physiopathology*; D006333:Heart Failure / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D008173:Lung Diseases, Obstructive / Q000188:drug therapy / Q000503:physiopathology*; D008297:Male; D010100:Oxygen / Q000502:physiology; D010726:Phosphodiesterase Inhibitors / Q000627:therapeutic use; D011659:Pulmonary Gas Exchange / Q000502:physiology; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013147:Spirometry / Q000295:instrumentation*
D010726:Phosphodiesterase Inhibitors; D002245:Carbon Dioxide; D010100:Oxygen
Vergleich der vier verschiedenen Methoden zur respiratorischen Bestimmung der anaeroben Schwelle bei Normalpersonen, Herz- und Lungenkranken.