Fig. 4

Relationship between actual stroke volume (aSV) and alveolar ventilation (\( \dot{\mathrm{V}} \)A). Markers indicate individual data of aSV (L) and \( \dot{\mathrm{V}} \)A (L/min). a The results at 6 Hz. b The results at 8 Hz. Dotted curves are exponential approximations. In a (6 Hz), the exponentials (coefficient of correlations (R), P values) are as follows: R100 (IT = 50%), 1.499 (R = 0.988, P < 0.001); 3100B (IT = 50%), 1.301 (R = 0.988, P < 0.001); and 3100B (IT = 33%), 1.125 (R = 0.991, P < 0.001). In the b (8 Hz), the exponentials (R, P values) are as follows: R100 (IT = 50%), 1.571 (R = 0.991, P < 0.001); 3100B (IT = 50%), 1.309 (R = 0.986, P < 0.001); and 3100B (IT = 33%), 1.140 (R = 0.991, P < 0.001)