Outcomes of Noninvasive Positive Pressure Ventilation in Acute Respiratory Distress Syndrome and Their Predictors: A National Cohort

Table 1

Patient and hospital characteristics, ARDS etiologies, comorbidities, and complications, by the study group.

	IMV (N = 14,550)		NIPPV (N = 6,835)		NIPPV success (N = 5,480)		NIPPV failure (N = 1,355)
	%	95% CI	%	95% CI	%	95% CI	%	95% CI
Patient-level characteristics
Age at admission (years), mean	56.3	[55.7, 57]	61.5	[60.6, 62.4]	62.2	[61.1, 63.2]	58.8	[56.9, 60.6]
Sex, %
Male (n = 2,149)	52.1	[50.2, 53.9]	46.4	[43.7, 49.1]	45.3	[42.3, 48.4]	50.7	[44.8, 56.7]
Female (n = 2,127)	47.9	[46.1, 49.8]	53.6	[50.9, 56.3]	54.7	[51.6, 57.7]	49.3	[43.3, 55.2]
Race (uniform)
White (n = 2,471)	63.3	[61.2, 65.3]	54.9	[51.7, 58.1]	53.4	[50.0, 56.7]	61.2	[54.5, 67.6]
Black (n = 815)	18.3	[16.7, 20.1]	23.4	[20.8, 26.2]	25	[22.2, 28.0]	16.7	[12.5, 21.9]
Hispanic (n = 492)	11.5	[10.1, 13.0]	13.2	[11.2, 15.6]	13.2	[11.0, 15.7]	13.6	[9.7, 18.6]
Asian/Pacific Islander (n = 142)	3.2	[2.6, 3.9]	4.2	[3.2, 5.5]	4.4	[3.3, 6.0]	3.1	[1.6, 6.1]
Native American (n = 25)	0.7	[0.4, 1.2]	0.5	[0.2, 1.0]	0.4	[0.1, 1.0]	0.8	[0.2, 3.1]
Other (n = 135)	3	[2.4, 3.8]	3.9	[2.9, 5.2]	3.7	[2.7, 5.0]	4.7	[2.7, 7.9]
Location/teaching status of hospital, %
Rural (n = 263)	5.6	[4.9, 6.4]	7.3	[5.9, 9.0]	6.5	[5.1, 8.3]	10.7	[7.6, 14.9]
Urban, nonteaching (n = 931)	21	[19.4, 22.6]	23.4	[20.7, 26.4]	23.1	[20.2, 26.3]	24.7	[19.7, 30.5]
Urban, teaching (n = 3,083)	73.4	[71.6, 75.1]	69.3	[66.1, 72.3]	70.4	[67.0, 73.6]	64.6	[58.3, 70.4]
Hospital-level characteristics
Region of hospital, %
Northeast (n = 826)	17.4	[15.8, 19.2]	23.3	[20.3, 26.7]	24.5	[21.0, 28.2]	18.8	[14.3, 24.4]
Midwest (n = 846)	22.4	[20.3, 24.7]	14.2	[11.7, 17.1]	13.2	[10.7, 16.3]	18.1	[13.7, 23.4]
South (n = 1,724)	39.3	[37.1, 41.6]	42.4	[39.0, 46.0]	42.4	[38.7, 46.2]	42.4	[36.0, 49.2]
West (n = 881)	20.9	[19.0, 22.8]	20	[17.5, 22.8]	19.9	[17.1, 23.0]	20.7	[16.0, 26.3]
ARDS etiologies
Sepsis, %, (n = 1,885)	50.8	[48.9, 52.6]	29.8	[27.4, 32.4]	21.4	[19.0, 23.9]	64.2	[58.3, 69.7]
Pneumonia, %, (n = 1,654)	42.3	[40.5, 44.2]	30.9	[28.5, 33.4]	24.6	[22.2, 27.3]	56.1	[50.1, 61.9]
Acute pancreatitis, %, (n = 138)	3.7	[3.1, 4.5]	2.1	[1.5, 3.0]	2	[1.3, 3.0]	2.6	[1.2, 5.3]
TRALI, %, (n = 16)	0.4	[0.3, 0.8]	0.2	[0.1, 0.7]	0.1	[0.0, 0.6]	0.7	[0.2, 2.9]
Trauma, %, (n = 392)	11.2	[9.9, 12.6]	4.9	[3.9, 6.2]	4.8	[3.7, 6.3]	5.2	[3.1, 8.5]
Comorbidities
COPD, %, (n = 1,016)	20.1	[18.7, 21.7]	31.5	[29.0, 34.0]	31	[28.3, 33.9]	33.2	[27.7, 39.2]
Chronic CHF, %, (n = 441)	9.2	[8.2, 10.3]	12.7	[11.0, 14.6]	13.9	[11.9, 16.0]	8.1	[5.3, 12.3]
Chronic IHD, %, (n = 935)	19.9	[18.3, 21.5]	26.1	[23.8, 28.5]	28.4	[25.8, 31.1]	17	[13.1, 21.7]
CKD, %, (n = 1,116)	21.3	[19.8, 22.8]	36.4	[33.8, 39.0]	39.1	[36.2, 42.0]	25.5	[20.7, 31.0]
Chronic liver disease, %, (n = 394)	10.4	[9.4, 11.6]	6.6	[5.4, 8.0]	4.7	[3.6, 6.0]	14.4	[10.7, 19.0]
Malignant neoplasms, %, (n = 402)	9.2	[8.2, 10.4]	9.8	[8.3, 11.5]	9.6	[8.0, 11.5]	10.7	[7.6, 14.9]
Dementia, %, (n = 172)	3.4	[2.8, 4.1]	5.3	[4.2, 6.7]	5.6	[4.3, 7.2]	4.4	[2.5, 7.6]
Hypertension, %, (n = 2,695)	57.9	[55.9, 59.8]	74	[71.5, 76.2]	77.5	[74.9, 79.9]	59.8	[53.5, 65.8]
DM with/without complications, %, (n = 1,413)	30.1	[28.3, 31.9]	39.4	[36.8, 42.0]	41.9	[39.0, 44.8]	29.2	[24.2, 34.7]
Obesity, %, (n = 847)	18.2	[16.8, 19.7]	23.1	[20.9, 25.5]	23.2	[20.7, 25.8]	22.9	[18.1, 28.4]
Smoking, %, (n = 795)	18.9	[17.4, 20.4]	18	[16.0, 20.2]	17.6	[15.3, 20.2]	19.6	[15.3, 24.7]
Complications
Shock state, (n = 1,378)	40.8	[38.9, 42.7]	14	[12.2, 15.9]	6.8	[5.5, 8.5]	42.8	[37.1, 48.7]
Acute kidney failure, %, (n = 1,890)	49.6	[47.7, 51.4]	32.8	[30.3, 35.4]	27.3	[24.7, 30.0]	55	[48.9, 60.9]
Acute liver failure, %, (n = 218)	6.7	[5.8, 7.7]	1.8	[1.2, 2.6]	0.8	[0.4, 1.6]	5.5	[3.4, 8.9]
DIC and coagulopathy, %, (n = 101)	2.7	[2.2, 3.4]	1.5	[1.0, 2.4]	0.5	[0.2, 1.1]	5.9	[3.6, 9.6]

n: actual number of observations; N: population-weighted sample size; CI: confidence interval; ARDS: acute respiratory distress syndrome; IMV: invasive mechanical ventilation; NIPPV: noninvasive positive pressure ventilation; TRALI: transfusion-related acute lung injury; COPD: chronic obstructive pulmonary disease; CHF: congestive heart failure; IHD: ischemic heart disease; CKD: chronic kidney disease; DM: diabetes mellitus; DIC: disseminated intravascular coagulopathy.