Medicine of the Future in America

Cardiorespiratory Effects of Pressure-controlled Ventilation With and Without Inverse Ratio in the Adult Respiratory Distress Syndrome: Results

Cardiorespiratory Effects of Pressure-controlled Ventilation With and Without Inverse Ratio in the Adult Respiratory Distress Syndrome: ResultsTable 1 summarizes the main characteristics of the population studied. All patients suffered from ARDS for 48 h or less, with a lung injury score ranging from 2.75 to 3.25. Patient 7 had a history of chronic bronchitis. No other patient had experienced previous pulmonary disease. Main results are expressed in Table 2. The only significant difference between VCV and PCV was a lower pPaw in PCV (p<0.05); this difference was found in all patients. The use of PC-IRV induced an increase in PEEPi and mPaw (p<0.05) and a decrease in pPaw (p<0.05) without change in Pplat. No significant differences in Pa02 were observed among the three modes. Notably, we did not observe a significant increase in Pk02 with PC-IRV. In 3 patients, we observed a more than 20 percent difference in Pa02 between VCV and PC-IRV; Pa02 was higher with PC-IRV in 2 and lower in 1.

The PaC02 was significantly lower with PC-IRV (39 ±4 mm Hg) than with PCV (43 ±5 mm Hg) or with VCV (45 ± 5 mm Hg) (p<0.05). The Cl and Do2 were lower with PC-IRV (3.3 ±0.2 L/min/m2 and 424 ± 28 ml/min/m2, respectively) than with PCV (3.6 ±0.2 L/min/m2 and 451 ±35 ml/min/ m2) or with VCV (3.7 ± 0.2 L/min/m2 and 469 ± 38 ml/ min/m2), although the difference was statistically significant only between PC-IRV and VCV (p<0.05). The mixed-venous oxygen pressure (PvOJ was significantly lower with PC-IRV than with VCV (p<0.05). No differences in Vo2 were observed among the three modes. The mean basal value of blood lactate concentration was 1.95 ±0.3 mmol/L. Four out of the 10 patients had a blood lactate level higher than 2 mmol/ L. Coronary Angiography

Table 2—Cardiorespiratory Data in Three Ventilatory Modes

Data* vcvt PCV* PC-IRV
pPaw, cm H20 38.0± 1.3 34.1.4§ 31.3± 1.3||
mPaw, cm H20 16.4 ±0.5 17.1 ±0.7 21.4±0.7||
PEEP, cm H20 9.7±0.5 9.6±0.5 3.6 ± 0.5Ц
PEEPi, cm H20 1.4±0.3 1.6±0.3 8.4 ± 0.9||
PEEPt, cm HeO 11.1±0.6 11.2±0.6 12.1 ±0.8
Pplat, cm HsO 28.9± 1.4 29.0± 1.4 28.9± 1.0
Pa02, mm Hg 83±6 77 ±6 87 ±9
Pv02, mm Hg 38± 1 36± 1 35±1§
PaC02, mm Hg 45±5 43±5 39 ±4||
HR, beats per min 122 ±6 124 ±6 121 ±6
MAP, mm Hg 83±4 78 ±3 78 ±3
Cl, L/min/m2 3.7±0.2 3.6 ±0.2 3.3±0.2§
Do2, ml/min/m* 469 ±38 451 ±35 424±28§
Vo2, ml/min/m2 111 ±10 116±10 113 ±10
This entry was posted in ARDS and tagged airway pressures, ards, inspiratory time, ventilatory modes.
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