Comparison of non-invasive to invasive oxygenation ratios for diagnosing acute respiratory distress syndrome following coronary artery bypass graft surgery: a prospective derivation-validation cohort study

Table 1 Demographic and clinical data

Variables	Total	Derivation group	Validation group	P-value
Age Mean ± SD	70.17 ± 12.17	69.21 ± 12.18	70.64 ± 12.16	0.20
Sex, Female (%)	270 (50.7)	90 (51.4)	180 (50.3)	0.80
DoI, hours Mean ± SD	49.14 ± 27.63	47.12 ± 29.07	50.12 ± 26.88	0.24
P_AO₂ Mean ± SD	228.54 ± 24.30	225.83 ± 23.17	229.86 ± 24.75	0.07
P_aO₂ Mean ± SD	94.15 ± 3.30	93.21 ± 3.89	94.62 ± 2.87	0.20
S_PO₂ Mean ± SD	94.13 ± 1.69	94.05 ± 1.60	94.17 ± 1.75	0.46
pH Mean ± SD	7.41 ± 0.06	7.40 ± 0.06	7.42 ± 0.06	0.07
P_aCO₂ Mean ± SD	45.41 ± 3.77	44.71 ± 4.36	45.75 ± 3.39	0.09
F_iO₂ Mean ± SD	27.61 ± 2.85	27.6 ± 3.12	27.61 ± 2.72	0.96
Hgb Mean ± SD	11.19 ± 1.52	10.86 ± 1.63	11.35 ± 1.43	< 0.001
P/F Mean ± SD	344.76 ± 38.28	342.09 ± 41.79	346.07 ± 36.42	0.26
P_A/F Mean ± SD	837.19 ± 126.70	828.94 ± 127.32	841.23 ± 126.37	0.29
S/F Mean ± SD	344.39 ± 34.16	344.78 ± 36.22	384.00 ± 33.21	0.856
OI Mean ± SD	4258.47 ± 809.76	4281.55 ± 765.33	4247.19 ± 831.42	0.65
OSI Mean ± SD	4254.35 ± 796.11	4230.81 ± 703.39	4265.86 ± 838.41	0.63
Survival, alive n (%)	446 (83.7)	150 (85.7)	296 (82.7)	0.37

DoI means duration of intubation; P_AO₂ means partial pressure of O₂ in alveoli; P_aO₂means partial pressure of O₂ in arterial blood; S_pO₂ means peripheral capillary oxygen saturation; P_aCO₂ means partial pressure of CO₂ in arterial blood; F_iO₂ means fraction of inspired oxygen; Hgb means hemoglobin; S/F means S_PO₂/FiO₂ ratio; P/F means P_aO₂/FiO₂ratio; P_A/F means P_AO₂/FiO₂ ratio; OI means Oxygen Index; OSI means Oxygen Saturation Index

ISSN: 1749-8090