Table 1.

Demographic and clinical characteristics of 1439 cardiac intensive care unit patients with planned extubation.

Variable	Weaned within 24 h (n = 1042)	Not Weaned within 24 h (n = 397)	p-Value
Gender			0.069
Males	714 (68.5%)	252 (63.5%)
Females	328 (31.5%)	145 (36.5%)
age, mean ± SD	65.05 ± 12.53	68.34 ± 15.18	<0.001	*
Smoking, n (%)			<0.001	*
No	805 (77.3%)	250 (63.0%)
Yes	198 (19.0%)	113 (28.5%)
Yes, quit smoking	39 (3.7%)	34 (8.6%)
Ventilation set, mean ± SD
Ventilation rate set, 30/min	12.23 ± 1.08	14.77 ± 8.77	<0.001	*
Inspiration time, breath/min	1.00 ± 0.00	4.08 ± 8.72	<0.001	*
Pressure limit high, cmH2O	40.72 ± 1.89	37.00 ± 6.75	<0.001	*
Pressure limit low, cmH2O	2.99 ± 0.40	3.91 ± 1.10	<0.001	*
Spontaneous respiratory rate, %	13.38 ± 2.92	20.22 ± 6.45	<0.001	*
Inspiratory pressure, cmH2O	20.74 ± 2.52	19.69 ± 5.84	<0.001	*
PEEP, cmH2O	5.47 ± 0.92	4.37 ± 2.69	<0.001	*
Ramp, mS	0.01 ± 0.13	0.24 ± 0.73	<0.001	*
Ventilation monitoring, mean ± SD
Inspiratory tidal volume, mL/kg	554.92 ± 84.93	422.41 ± 336.91	<0.001	*
Expiratory tidal volume, mL/kg	555.55 ± 80.85	507.98 ± 156.23	<0.001	*
Peak pressure, cmH2O	21.05 ± 2.85	211.52 ± 273.68	<0.001	*
Mean pressure, cmH2O	8.75 ± 1.33	13.37 ± 7.38	<0.001	*
Expiratory minute ventilation, L/min	7.26 ± 1.72	10.49 ± 4.13	<0.001	*
Compliance, mL/cmH2O	60.04 ± 29.42	28.78 ± 35.06	<0.001	*
Resistance, mL/cmH2O	13.68 ± 5.43	28.95 ± 33.67	<0.001	*
Arterial blood gas test, ABG, mean ± SD
SpO2, %	99.36 ± 31.84	63.59 ± 36.53	<0.001	*
pH	7.03 ± 0.18	7.04 ± 0.18	0.947
PCO2, mmHg	37.33 ± 8.15	32.03 ± 11.89	<0.001	*
HCO3, mmol/L	23.57 ± 4.06	29.36 ± 11.29	<0.001	*
PO2, mmHg	162.86 ± 96.22	72.75 ± 102.14	<0.001	*
SAO2, %	154.74 ± 140.22	230.17 ± 172.74	<0.001	*
Base Excess, mmol/L	2.99 ± 21.32	36.83 ± 49.32	<0.001	*
Others, mean ± SD
Systolic blood pressure, mmHg	124.55 ± 24.57	97.67 ± 33.42	<0.001	*
Diastolic blood pressure, mmHg	66.50 ± 26.76	93.78 ± 41.28	<0.001	*
Heart rate, bpm	82.42 ± 14.98	106.87 ± 28.78	<0.001	*

*: p-value < 0.05.