Table 3

Comparison of complications over the course of mechanical ventilation in each body mass index groups

Underweight (BMI <18.5 kg/m2)Normal (BMI 18.5–24.9 kg/m2)Overweight (BMI 25–29.9 kg/m2)Obese (BMI 30–39.9 kg/m2)Severely obese (BMI >40 kg/m2)p-Value
N (% (95% CI))184 (3.7% (3.2 to 4.3))1995 (40.1% (38.8 to 41.5))1781 (35.8% (34.5 to 37.2))792 (15.9%; (14.9 to 16.9))216 (4.3%; (3.8 to 4.9))
Barotrauma, N (% (95% CI))8 (4.3% (1.9 to 8.4))63 (3.1% (2.4 to 4.0))54 (3.0% (2.3 to 3.9))27 (3.4% (2.2 to 4.9))5 (2.3% (0.7 to 5.3))0.807
Ventilator associated pneumonia, N (% (95% CI))9 (4.9% (2.3 to 9.1))68 (3.4% (2.6 to 4.3))72 (4.0% (3.2 to 5.1))36 (4.5% (3.2 to 6.2))12 (5.5% (2.9 to 9.5))0.380
Sepsis, N (% (95% CI))22 (11.9% (7.6 to 19.5))158 (7.9% (6.7 to 9.2))155 (8.7% (7.4 to 10.1))50 (6.3% (4.7 to 8.2))15 (6.9% (3.9 to 11.1))0.076
Cardiovascular failure, N (% (95% CI))60 (32.6% (25.9 to 39.9))620 (31.1% (29.0 to 33.1))587 (32.9% (30.8 to 35.2))224 (28.3% (25.1 to 31.5))63 (29.2% (23.2 to 35.7))0.179
Respiratory failure, N (% (95% CI))
With criteria of acute respiratory distress syndrome11 (5.9% (3.0 to 10.4))89 (4.5% (3.6 to 5.5))102 (5.7% (4.7 to 6.9))55 (6.9% (5.3 to 8.9))19 (8.8% (5.4 to 13.4))0.021
Without criteria of acute respiratory distress syndrome42 (22.8% (16.9 to 29.6))556 (27.9% (25.9 to 29.9))557 (31.3% (29.1 to 33.5))256 (32.3% (29.1 to 35.7))81 (37.5% (31.0 to 44.3))0.002
Acute renal failure, N (% (95% CI))12 (6.5% (3.4 to 11.1))123 (6.2% (5.1 to 7.3))150 (8.4% (7.2 to 9.8))71 (8.9% (7.1 to 11.2))26 (12.0% (8.0 to 17.1))0.003
Hepatic failure, N (% (95% CI))9 (4.9% (2.3 to 9.1))100 (5.0% (4.1 to 6.1)83 (4.7 (3.7 to 5.7))42 (5.3% (3.8 to 7.1))18 (8.3% (5.0 to 12.8))0.239
Haematologic failure, N (% (95% CI))21 (11.4% (7.2 to 16.9))143 (7.2% (6.1 to 8.4))127 (7.1% (5.9 to 8.4))49 (6.2% (4.6 to 8.1))14 (6.5% (3.6 to 10.6))0.177