1 Introduction
2 Methods
2.1 Study design
2.2 Raw data acquisition
2.3 Derivation and calculation of ventilation-related parameters
2.4 Statistical analysis
3 Results
3.1 MP by Gattinoni’s equation and PV loop area
Variables | Number (%) or Median (IQR) |
---|---|
Age (year) | 63 (52–75) |
Male (n, %) | 17 (68%) |
Height (cm) | 160 (156–169) |
Body Mass Index (Kg/m2) | 24.68 (22.73–27.78) |
ARDS (Y/N) | 7/18 |
Respiratory rate (min−1) | 18 (14–20) |
Ventilator mode PCV: VCV | 22:3 |
Monitored VT (ml) | 542 (500–603) |
Driving pressure (cmH2O) | 20 (18–22) |
PEEP (cmH2O) | 6 (5–8) |
Static compliance (ml/cmH2O) | 27.1 (23.81–31.25) |
PaO2/FIO2 (mmHg) | 271 (136–361) |
A-a DO2 (mmHg) | 185 (96–315) |
PaCO2 (mmHg) | 32 (25–39) |
3.2 Assessing effects of PEEP on MP by both methods
Power by Gattinoni Equation (J/min) | Power by hysteresis area of PV loop (J/min) | |||||
---|---|---|---|---|---|---|
PEEP 5 cmH2O | PEEP 10 cmH2O | P | PEEP 5 cmH2O | PEEP 10 cmH2O | P | |
Non-ARDS (n = 18) | ||||||
VT 6 ml/kg | 5.07 (4.34, 7.56) | 8.50 (6.94, 10.38) | < 0.001 | 6.51 (4.22, 9.69) | 6.29 (4.25, 10.27) | 0.381 |
VT 8 ml/kg | 7.15 (6.04, 9.82) | 10.62 (9.63, 15.06) | 0.001 | 9.56 (6.13, 13.16) | 8.82 (7.24, 13.82) | 0.868 |
VT 10 ml/kg | 10.08 (7.69, 13.77) | 14.81 (12.9, 19.98) | < 0.001 | 13.29 (7.94, 20.28) | 12.30 (8.56, 19.38) | 0.435 |
ARDS (n = 7) | ||||||
VT 6 ml/kg | 2.63 (1.27, 3.44) | 2.80 (0.6, 4.72) | 0.735 | 6.41 (2.94, 12.38) | 8.50 (4.59, 12.69) | 0.612 |
VT 8 ml/kg | 4.48 (3.26, 6.76) | 4.44 (2.79, 6.44) | 0.612 | 13.99 (6.44, 17.21) | 11.83 (8.32, 14.34) | 0.091 |
VT 10 ml/kg | 6.59 (4.58, 11.63) | 7.80 (5.94, 8.93) | 1 | 12.67 (10.68, 22.48) | 14.80 (6.58, 21.97) | 0.735 |
All (n = 25) | ||||||
VT 6 ml/kg | 4.51 (3.46, 7.16) | 7.21 (3.85, 9.49) | < 0.001 | 6.46 (4.21, 10.48) | 6.47 (4.33, 10.84) | 0.331 |
VT 8 ml/kg | 6.84 (4.62, 9.12) | 9.97 (6.09, 13.68) | 0.001 | 9.71 (6.35, 15.38) | 9.71 (8.05, 14.15) | 0.361 |
VT 10 ml/kg | 9.76 (6.82, 12.25) | 13.68 (8.28, 16.49) | 0.001 | 12.98 (8.86, 21.28) | 14.52 (8.34, 19.65) | 0.607 |