Effects of positive end-expiratory pressure strategy in supine and prone position on lung and chest wall mechanics in acute respiratory distress syndrome

Annals of Intensive Care

Table 2 Respiratory mechanics in early and late prone position according to PEEP strategy

Variables	Early prone position		Late prone position		P values
	PEEP/F_IO₂ table group (n = 19)	Pes-guided group (n = 19)	PEEP/F_IO₂ table group (n = 19)	Pes-guided group (n = 17)	Time effect	PEEP strategy effect	Time and PEEP interaction
PEEP set on ventilator (cmH₂O)	10 ± 2	12 ± 5	10 ± 2	12 ± 4	0.53	0.23	0.50
Paw,ee (cmH₂O)	11 ± 3	13 ± 5	11 ± 3	13 ± 4	0.93	0.09	0.26
Paw,ei (cmH₂O)	22 ± 4	23 ± 5	22 ± 4	24 ± 4	0.79	0.28	0.67
Pes,ee (cmH₂O)	9 ± 4	10 ± 5	9 ± 4	10 ± 6	0.88	0.47	0.07
Pes,ei (cmH₂O)	12 ± 5	14 ± 4	12 ± 5	14 ± 5	0.87	0.20	0.07
Pga,ee (cmH₂O)	18 ± 5	17 ± 6	17 ± 4	17 ± 5	0.48	0.96	0.77
Pga,ei (cmH₂O)	20 ± 5	20 ± 6	19 ± 4	19 ± 6	0.43	0.96	0.75
P_L,ee (cmH₂O)	2 ± 4	3 ± 1	2 ± 4	3 ± 2	0.82	0.22	0.38
P_L,ei (cmH₂O)	10 ± 6	9 ± 3	10 ± 5	10 ± 4	0.95	0.69	0.11
P_L,ei_Elastance (cmH₂O)	16 ± 5	14 ± 5	15 ± 4	14 ± 5	0.96	0.47	0.16
DPrs (cmH₂O)	11 ± 4	10 ± 3	11 ± 4	11 ± 4	0.79	0.51	0.17
DPcw (cmH₂O)	3 ± 1	4 ± 1	3 ± 1	4 ± 1	0.52	0.02	0.42
DP_L (cmH₂O)	8 ± 4	6 ± 3	8 ± 4	7 ± 3	0.82	0.19	0.14
Est,rs (cmH₂O/L)	34 ± 18	29 ± 11	33 ± 16	30 ± 12	0.76	0.41	0.24
Est,cw (cmH₂O/L)	9 ± 3	12 ± 4	9 ± 3	11 ± 5	0.59	0.04	0.37
Est,L (cmH₂O/L)	26 ± 18	18 ± 11	24 ± 16	19 ± 10	0.56	0.18	0.12
PaCO₂ (mmHg)	50 ± 13	55 ± 13	45 ± 14	48 ± 10	< 0.001	0.42	0.43
PaO₂/F_IO₂ ratio (mmHg)	178 ± 55	193 ± 48	223 ± 85	218 ± 65	< 0.001	0.82	0.27
EELV (mL)	1341 ± 440	1342 ± 445	1504 ± 547	1691 ± 950	0.01	0.63	0.28

Values are mean ± SD
PEEP positive end-expiratory pressure, Paw,ee static end-expiratory pressure of the respiratory system, Paw,ei static end-inspiratory pressure of the respiratory system, Pes,ee static end-expiratory esophageal pressure, Pes,ei static end-inspiratory esophageal pressure, Pga,ee static end-expiratory gastric pressure, Pga,ei static end-inspiratory gastric pressure, P_L,ee static end-expiratory transpulmonary pressure, P_L,ei static end-inspiratory transpulmonary pressure, P_L,ei _Elastance Paw,ei x Est,L/Est,rs, Est,rs, Est,cw, Est,L static elastance, of respiratory system, chest wall and lung, respectively, DPrs, DPcw, DPL driving pressure of respiratory system, chest wall and lung, respectively, EELV end-expiratory lung volume