Table 1 Comparison of V/Q mismatch indices between absolute and relative V/Q
All patients (n = 25) | Patients with VA/QC > 1 (n = 21) | Patients with VA/QC < 1 (n = 4) | |||||||
|---|---|---|---|---|---|---|---|---|---|
Absolute V/Q | Relative V/Q | p | Absolute V/Q | Relative V/Q | p | Absolute V/Q | Relative V/Q | p | |
Alveolar ventilation (L min−1) | 7.9 (7.5; 9.3) | 7.9 (7.6; 9.3) | NA | 7.7 (6.8; 9.6) | NA | ||||
Cardiac output (L min−1) | 6.3 (5.0; 8.5) | 5.9 (4.9; 7.7) | NA | 9.0 (8.6; 11.4) | NA | ||||
Pixels with | |||||||||
Shunt (V/Q ≤ 0.1) (%) | 11 (7; 15) | 11 (7; 15) | 1 | 11 (7; 15) | 11 (7; 15) | 1 | 16 (5; 30) | 16 (5; 30) | NA |
Low V/Q (0.1 < V/Q < 0.8) (%) | 19 (6; 28.0) | 23 (18; 36) | 0.002 | 10 (5; 25) | 23 (17; 35) | < 0.0001 | 40 (31; 50) | 22 (16; 26) | NA |
Normal V/Q (0.8 ≤ V/Q ≤ 1.25) (%) | 17 (11; 22) | 24 (15; 45) | 0.03 | 17 (11; 28) | 28 (14; 48) | 0.19 | 17 (9; 18) | 85 (48; 109) | NA |
High V/Q (1.25 < V/Q < 10) (%) | 27 (12; 48) | 15 (12; 22) | < 0.001 | 33 (25; 54) | 15 (12; 23) | < 0.0001 | 9 (5; 12) | 12 (8; 16) | NA |
Dead space (V/Q ≥ 10) (%) | 17 (7; 24) | 17 (7; 24) | 1 | 17 (6; 22) | 17 (6; 22) | 1 | 21 (12; 28) | 21 (12; 28) | NA |
Shunt fraction (%) | 31 (12; 65) | 41 (26; 67) | 0.006 | 19 (11; 46) | 37 (24; 66) | < 0.0001 | 70 (64; 82) | 56 (41; 70) | NA |
Dead space fraction (%) | 56 (41–83) | 40 (23; 67) | 0.0001 | 58 (46; 84) | 40 (22; 49) | < 0.0001 | 33 (30; 34) | 39 (34; 40) | NA |
Wasted ventilation (%) | 29 (18; 35) | 19 (11; 29) | < 0.001 | 29 (19; 35) | 16 (11; 27) | < 0.0001 | 23 (17; 28) | 25 (20; 30) | NA |
Wasted perfusion (%) | 13 (7; 22) | 19 (11; 23) | 0.005 | 11 (7; 19) | 18 (11; 23) | < 0.0001 | 27 (19; 34) | 21 (15; 27) | NA |