Table 3.

Separate regional computed tomographic analysis of normally aerated/poorly aerated and nonaerated lung regions

Parameter	PEEP	ZEEP	p
Regional analysis performed in poorly aerated and nonaerated lung regions
Lung volume, gas + tissue (ml)	1,438 ± 582	1,068 ± 424	< 0.001
Volume of gas (ml)	561 ± 325	188 ± 109	< 0.001
Volume of tissue (ml)	877 ± 361	880 ± 376	NS
Regional analysis performed in normally aerated lung regions
Lung volume, gas + tissue (ml)	1,940 ± 985	1,220 ± 696	< 0.001
Volume of gas (ml)	1,474 ± 779	803 ± 515	< 0.001
Volume of tissue (ml)	466 ± 212	416 ± 190	< 0.001

ZEEP, zero end-expiratory pressure; PEEP, positive end-expiratory pressure of 15 cmH₂O.