Low tidal volume ventilation ameliorates left ventricular dysfunction in mechanically ventilated rats following LPS-induced lung injury

Table 2 Respiratory, hemodynamic and left ventricular measurements throughout the experiment in the rats (n = 20)

Variable	LTV	LTV + LPS	HTV	HTV + LPS
Respiration
pH	7.31 ± 0.01	7.26 ± 0.02^a,c	7.36 ± 0.01^a	7.28 ± 0.02^a,c
PaCO₂ (torr)	39.1 ± 1.7	47.0 ± 3.0^a,c,d	35.8 ± 1.3	37.8 ± 1.8
PaO₂/FiO₂ (torr)	534 ± 36	501 ± 23	485 ± 33	324 ± 28^a,b,c
Pmean (cmH₂O)	7.6 ± 0.3	7.8 ± 0.2	8.3 ± 0.2^a,b	8.9 ± 0.2^a,b,c
Hemodynamics
MAP (mmHg)	115 ± 8	116 ± 6	104 ± 6^a,b	98 ± 8^a,b
CVP (mmHg)	1.9 ± 0.3	2.2 ± 0.6	1.1 ± 0.3^a,b	0.7 ± 0.3^a,b
HR (beats/min)	393 ± 13	413 ± 9	362 ± 12^a,b,d	403 ± 9
LV parameters
ESP (mmHg)	184 ± 12^b,d	154 ± 10	167 ± 12	146 ± 14
EDP (mmHg)	20 ± 4	17 ± 5	18 ± 2	17 ± 3
dP/dt_max (mmHg/s)	11740 ± 1114	11763 ± 1251	10343 ± 1000	9014 ± 682^a,b
dP/dt_min (mmHg/s)	−13482 ± 1485	−13072 ± 1103	−11267 ± 990	−8555 ± 1005^a,b,c
Ees/Ea	1.67 ± 0.33	1.45 ± 0.16	1.33 ± 0.13	0.86 ± 0.11^a,b,c

LTV low tidal volume ventilation, LPS lipopolysaccharide, HTV high tidal volume ventilation, CVP central venous pressure, dP/dt_max maximum rate of pressure development, dP/dt_min maximum rate of pressure decline, EDP end-diastolic pressure, ESP end-systolic pressure, Ees/Ea end-systolic elastance/effective arterial elastance ratio, HR heart rate, MAP mean arterial pressure, PaCO₂ arterial partial pressure of carbon dioxide, PaO₂/FiO₂ arterial partial pressure of oxygen/fraction of inspired oxygen ratio, Pmean mean airway pressure
^aP < 0.05 compared to LTV group. ^bP < 0.05 compared to LTV + LPS group. ^cP < 0.05 compared to HTV group. ^dP < 0.05 compared to HTV + LPS group. Data are mean values ± SE

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