Variable | Baseline | 30 | 60 | 90 |
---|---|---|---|---|
Values are mean (SEM). | ||||
V˙E, Pulmonary ventilation; V˙A, alveolar ventilation; Vt, tidal volume; fb, respiratory frequency; Vd, physiological dead space; Tlco, carbon monoxide transfer factor; Va, alveolar volume; FVC, forced vital capacity; FEV1, forced expired volume in one second; FEF25–75%, forced mid-expiratory flow; Peto2, partial pressure of end tidal O2; Petco2, partial pressure of end tidal CO2; Vo2, oxygen uptake; Vco2, carbon dioxide output; RQ, respiratory quotient; Pao2, arterial partial pressure of O2; Paco2, arterial partial pressure of CO2; Sao2, arterial O2 saturation; A-aDo2, alveolar-arterial O2 tension difference; PCV, packed cell volume; Hb, haemoglobin; SBP, systolic blood pressure; DBP, diastolic blood pressure; MAP, mean arterial pressure; CI, cardiac index; SV, stroke volume; HR, heart rate; SVR, systemic vascular resistance. | ||||
*p<0.05; **p<0.01 compared with baseline (Wilcoxon sign rank test, using Friedman analysis of variance). | ||||
Ventilation | ||||
V˙E(l/min) | 9.5 (0.74) | 11.5 (0.74) | 9.5 (0.74) | 9.1 (0.42) |
V˙a(l/min) | 8.3 (0.57) | 9.3 (0.46) | 7.8 (0.6) | 7.2 (0.39) |
Vt (ml) | 768 (60.5) | 762 (71.1) | 768 (91.2) | 670 (51.3) |
fb (breaths/min) | 13.1 (1.13) | 15.7 (1.2) | 13.4 (1.2) | 14.2 (1.3) |
Vd/Vt | 0.16 (0.01) | 0.22 (0.02)* | 0.23 (0.02)* | 0.25 (0.01)* |
Spirometry and Tlco | ||||
Tlco (ml/min/mm Hg) | 37.8 (2.1) | 36.7 (2.1)* | 35.7 (1.4)** | 34.1 (1.7) |
Tlco/Va (ml/min/mm Hg) | 5.3 (0.2) | 5.2 (0.2) | 5.1 (0.2) | 4.8 (0.2)** |
FVC (litres) | 5.4 (0.9) | 5.2 (0.9) | 5.3 (0.9) | 5.3 (1.0) |
FEV1 (litres) | 4.3 (0.7) | 4.2 (0.7) | 4.3 (0.8) | 4.3 (0.8) |
FEF25–75% (l/s) | 4.2 (0.3) | 4.3 (0.3) | 4.2 (0.3) | 4.1 (0.3) |
Gas exchange | ||||
Peto2 (mm Hg) | 95.8 (1.0) | 89.1 (2.5) | 82.9 (2.8)* | 80.8 (3.7)* |
Petco2 (mm Hg) | 36.1 (0.9) | 33.4 (0.7)** | 34.5 (1.0) | 33.4 (0.8)* |
V˙o2 (ml/min) | 431 (24.2) | 521.5 (48.5) | 486.4 (33.4) | 461.5 (26.4) |
V˙co2 (ml/min) | 331.3 (25.8) | 418.8 (49.8) | 329.6 (26.8) | 297.6 (12.3) |
RQ | 0.77 (0.05) | 0.8 (0.04) | 0.68 (0.04) | 0.66 (0.05) |
V˙o2/V˙a | 52.6 (9.9) | 56.2 (10.5) | 64.0 (14.4)* | 65.6 (14.9) |
Pao2 (mm Hg) | 87.8 (1.5) | 75.9 (2.5)** | 77.3 (2.4)** | 69.5 (4.1)** |
Paco2 (mm Hg) | 37.4 (0.6) | 37.7 (0.2) | 37.7 (0.3) | 37.8 (0.4) |
Sao2 (%) | 98.6 (0.4) | 97.8 (0.3)* | 97.1 (0.5)** | 97.1 (0.6)** |
A-aDo2 (mm Hg) | 8.0 (2.0) | 13.3 (4.5) | 5.6 (2.8) | 11.3 (5.2) |
PCV | 0.42 (0.3) | 0.43 (0.05) | 0.42 (0.04) | 0.42 (0.05) |
Hb (g/l) | 146.20 (10.2) | 149.30 (8.6) | 148.70 (9.7) | 147.10 (8.1) |
Cardiovascular | ||||
SBP (mm Hg) | 127.4 (2.7) | 130.8 (3.1) | 120.9 (2.2) | 126.4 (3.4) |
DBP (mm Hg) | 73.3 (3.2) | 76.8 (4.2) | 71.4 (2.1) | 72.6 (2.3) |
MAP (mm Hg) | 91.3 (2.37) | 94.8 (2.55) | 87.9 (1.5) | 90.5 (2.1) |
CI (l/min/m2) | 4.1 (0.3) | 3.4 (0.4)* | 3.2 (0.3)** | 2.8 (0.3)* |
SV (ml) | 113.0 (9.7) | 117.0 (9.2)* | 95.4 (8.5) | 82.5 (6.6) |
HR (beats/min) | 75 (2.2) | 68 (4.0) | 67.4 (2.6) | 69.4 (4.2) |
SVR (mm Hg/l/min) | 11.4 (1.0) | 15.2 (2.3)* | 15.1 (2.3)* | 16.5 (1.8)* |