High-Flow Nasal Cannula versus Noninvasive Ventilation in AECOPD Patients with Respiratory Acidosis: A Retrospective Propensity Score-Matched Study

Table 1

Baseline characteristics at the time of ICU admission before propensity score matching.

Characteristics	Unmatched cohort (n = 151)
	Total (n = 151)	HFNC group (n = 48)	NIV group (n = 103)	value
Demographics
Age (years)	78.9 ± 8.3	78.6 ± 8.5	79.1 ± 8.3	0.762
Gender ((%) male)	68.9	75	66	0.267
BMI (kg/m^2)	22.8 ± 5.6	22.9 ± 6.0	22.6 ± 5.2	0.804
Pack year	39.0 (15.0–45.0)	32.5 (10.0–50.0)	40.0 (20.0–45.0)	0.963
FEV1%	31.5 ± 12.3	31.6 ± 12.3	31.5 ± 12.6	0.990
FEV1/FVC	48.6 ± 10.7	49.6 ± 14.8	48.3 ± 9.6	0.764
Vital signs
Body temperature (°C)	36.5 ± 0.5	36.6 ± 0.4	36.5 ± 0.5	0.195
Heart rate (beats/min)	89 ± 16	89 ± 13	90 ± 17	0.815
Respiratory rate (breaths/min)	22 ± 5	23 ± 4	22 ± 6	0.363
Systolic blood pressure (mmHg)	131 ± 21	129 ± 22	132 ± 21	0.479
Mean arterial pressure (mmHg)	89 ± 13	88 ± 12	91 ± 4	0.195
Severity score
Charlson	6 ± 2	6 ± 2	6 ± 2	0.104
APACHE II	16 ± 4	16 ± 4	16 ± 4	0.526
SAPS II	33 ± 7	32 ± 5	34 ± 7	0.209
GCS	15 ± 2	15 ± 1	14 ± 2	0.032
Echocardiography
LVEF (%)	68.8 ± 7.7	70.1 ± 4.8	68.2 ± 8.7	0.155
LVEDD (mm)	44.2 ± 6.4	43.9 ± 5.2	44.5 ± 6.9	0.584
RVEDD (mm)	22.1 ± 5.4	23.2 ± 6.7	22.0 ± 5.0	0.241
RVSP (mmHg)	38 (25–51)	39 (28–53)	36 (22–50)	0.375
Home NIV use no. (%)	34 (22.7)	5 (10.4)	29 (28.4)	0.014
Comorbidities, no. (%)
Pneumonia	28 (18.7)	9 (18.8)	19 (18.6)	0.986
Cor pulmonale	41 (27.3)	14 (29.2)	27 (26.5)	0.730
Heart failure	34 (22.7)	8 (16.7)	26 (25.5)	0.229
Hypertension	117 (78.0)	32 (66.7)	85 (83.3)	0.022
Coronary artery disease	40 (26.7)	8 (16.7)	32 (31.4)	0.057
Old myocardial infarction	18 (12)	4 (8.3)	14 (13.7)	0.343
Atrial fibrillation	33 (22.0)	10 (20.8)	23 (22.5)	0.813
OSAHS	7 (4.7)	3 (6.3)	4 (3.9)	0.681
Diabetes mellitus	39 (26)	5 (10.4)	34 (33.3)	0.003
Arterial blood gas
pH	7.34 ± 0.08	7.33 ± 0.07	7.34 ± 0.09	0.878
PaCO2 (mmHg)	69.6 ± 20.7	68.3 ± 20.8	70.3 ± 20.7	0.601
HCO3− (mmol/L)	36.6 ± 8.3	35.6 ± 7.4	37.1 ± 8.7	0.299
PaO2/FIO2 (mmHg)	206.4 ± 54.4	203.5 ± 55.6	207.7 ± 54.3	0.681
Laboratory parameters
White blood cell (×10^9)	9.36 (7.08–12.86)	8.73 (6.54–12.18)	9.84 (7.24–12.94)	0.304
Neutrophil (%)	80.3 ± 9.0	79.1 ± 9.3	80.9 ± 8.8	0.261
PCT (μg/L)	0.11 (0.10–0.20)	0.10 (0.10–0.15)	0.12 (0.10–0.25)	0.038
CRP (mg/L)	2.69 (1.00–8.20)	3.67 (1.10–8.43)	2.43 (0.91–8.65)	0.598
Albumin (g/L)	37.2 ± 5.3	36.3 ± 5.0	37.7 ± 5.4	0.126
Creatinine (μmol/L)	66.0 (55.0–87.0)	70.0 (59.3–90.0)	63.0 (55.0–87.0)	0.315
CCR (mL/min)	60.7 (48.9–82.1)	58.5 (52.2–69.0)	63.0 (45.6–86.9)	0.499
NT-proBNP (pg/dl)	1460.0 (411.0–3510.0)	1196.5 (367.0–2437.5)	1710.0 (472.0–3930.0)	0.123

Data are presented as mean ± standard deviation, median (interquartile range), no. (%), or %. APACHE, Acute Physiology and Chronic Health Evaluation; BMI, body mass index; CCR, creatinine clearance rate; CRP, C-reactive protein; FEV 1, forced expiratory volume in one second; FVC, forced vital capacity; GCS, Glasgow Coma Scale; HFNC, high-flow nasal cannula; ICU, intensive care unit; LVEDD, left ventricle end-diastolic diameter; LVEF, left ventricular ejection fraction; NIV, noninvasive ventilation; NT-proBNP, N-terminal pro-brain natriuretic peptide; OSAHS, obstructive sleep apnea and hypoventilation syndrome; RVEDD, right ventricle end-diastolic diameter; RVSP, right ventricular systolic pressure; PCT, procalcitonin; SAPS, Simplified Acute Physiology Score.