Positive Air-Test result (n=62) | Negative Air-Test result (n=108) | p Value | |
Demographic data | |||
Age, years | 65 (11) | 56 (17) | <0.001 |
Women, n (%) | 33 (6) | 56 (9) | 0.01 |
Height, cm | 164 (9) | 166 (9) | 0.06 |
Body weight, kg | 84 (21) | 73 (15) | <0.001 |
ARISCAT score | 26 (14) | 16 (15) | 0.01 |
Preoperative SpO2, % | 98 (1) | 98 (2) | 0.12 |
Lower abdominal surgery | 24 (38) | 34 (31) | 0.20 |
Upper abdominal surgery | 9 (14) | 13 (12) | 0.11 |
Peripheral surgery | 29 (46) | 60 (55) | 0.06 |
Duration of surgery, min | 137 (62) | 119 (63) | 0.27 |
Intraoperative ventilatory management | |||
Tidal volume, mL | 470 (52) | 460 (88) | 0.33 |
Respiratory rate, breaths/min | 12 (1) | 12 (2) | 1.00 |
PEEP, cmH2O | 6 (1) | 6 (2) | 1.00 |
FiO2 | 0.6 (0.2) | 0.7 (0.3) | 0.88 |
SpO2 and arterial blood gases in PACU at the end of the Air-Test | |||
Postoperative SpO2, % | 91 (3) | 99 (1) | 0.01 |
PaO2, mm Hg | 66 (10) | 87 (12) | 0.01 |
PaCO2, mm Hg | 41 (6) | 42 (6) | 0.29 |
pH | 7.37 (0.04) | 7.38 (0.03) | 0.06 |
MAP, mm Hg | 79 (12) | 85 (15) | 0.07 |
Lactate, mmol/L | 1.1 (0.4) | 1.0 (0.7) | 0.32 |
Hb, g/dL | 12.6 (1.7) | 12.9 (1.1) | 0.09 |
Temperature, °C | 36.4 (1.9) | 36.1 (2.1) | 0.41 |
VAS | 1 (1) | 1 (1) | 1.00 |
Data are described as the mean (±SD) or number/total number (%). The ARISCAT score was used to predict postoperative pulmonary complications.22
ARISCAT, Assess Respiratory Risk in Surgical Patients in Catalonia; FiO2, inspiratory oxygen fraction; Hb, haemoglobin; MAP, mean arterial pressure; PaCO2, carbon dioxide partial pressure; PACU, postanaesthesia care unit; PaO2, arterial oxygen partial pressure; PEEP, positive end-expiratory pressure; pH, acid–base status; SpO2, pulse oximetry haemoglobin saturation; VAS, visual analogue scale.