Table 1 Baseline characteristics and outcomes of patients initiated on HFNC
|  | Total HFNC (n = 81) | HFNC success (n = 67) | HFNC Failure (n = 14) | p-value |
|---|---|---|---|---|
Age | 59.0 (45.5–69.0) | 58.0 (46.0–69.0) | 60.0 (39.5–69.5) | 0.033* |
Male gender | 60 (74.1%) | 52 (77.6%) | 8 (57.1%) | 0.181 |
BMI | 25.1 (21.5–29.0) | 25.1 (20.5–29.0) | 25.3 (22.5–29.2) | 0.591 |
APACHE II (at ICU admission) | 27.0 (22.5–30.0) | 26.0 (22.0–30.0) | 28.0 (24.0–31.8) | 0.326 |
SOFA Score (at ICU admission) | 7.0 (4.0–9.0) | 7.0 (4.0–9.0) | 8.5 (3.8–11.3) | 0.020* |
Charlson Comorbidity Index | 3.0 (1.0–6.0) | 4.0 (1.0–6.0) | 3.0 (1.0–8.3) | 0.870 |
Diabetes mellitus | 26 (32.1%) | 22 (32.8%) | 4 (28.6%) | 0.760 |
Hypertension | 33 (40.7%) | 27 (40.3%) | 6 (42.9%) | 0.861 |
Ischaemic heart disease | 19 (23.5%) | 15 (22.4%) | 4 (28.6%) | 0.625 |
Chronic liver disease | 5 (6.2%) | 4 (6.0%) | 1 (7.1%) | 0.870 |
Chronic kidney disease | 9 (11.1%) | 8 (11.9%) | 1 (7.1%) | 0.609 |
Cerebrovascular accident | 11 (13.6%) | 9 (13.4%) | 2 (14.3%) | 0.934 |
Asthma/COPD | 7 (8.6%) | 6 (9.0%) | 1 (7.1%) | 0.829 |
Covid-19 | 6 (7.4%) | 4 (6.0%) | 2 (14.3%) | 0.424 |
Pneumonia | 62 (76.5%) | 52 (77.6%) | 10 (71.4%) | 0.625 |
Other respiratory conditions | 3 (3.7%) | 3 (4.5%) | 0 (0.0%) | 0.942 |
Immunocompromised | 7 (8.6%) | 5 (7.5%) | 2 (14.3%) | 0.415 |
Cuff leak | 69 (85.2%) | 58 (86.6%) | 11 (78.6%) | 0.450 |
Moderate–large respiratory secretions | 25 (30.9%) | 23 (34.3%) | 2 (14.3%) | 0.090 |
Vasopressor support at time of HFNC initiation | 6 (7.4%) | 2 (3.0%) | 4 (28.6%) | 0.064 |
Surgical cases | 29 (35.8%) | 24 (35.8%) | 5 (35.7%) | 0.994 |
GCS Motor Score at time of extubation | 6.0 (6.0–6.0) | 6.0 (6.0–6.0) | 6.0 (6.0–6.0) | 0.48 |
Fluid balance 24 h prior to extubation | 231.0 (−296.9–998.0) | 217.8 (−383.7–997.0) | 538.2 (−245.6–2839.1) | 0.240 |
Duration of MV days | 5.0 (3.0–8.0) | 5.0 (3.0–9.0) | 3.0 (2.0–6.5) | 0.301 |
Patients with at least one risk factor for extubation failure | 61 (75.3%) | 49 (73.1%) | 12 (85.7%) | 0.322 |
Patients with > / = 2 risk factors for extubation failure | 38 (46.9%) | 32 (47.8%) | 6 (42.9%) | 0.741 |
Vital signs pre-HFNC initiation | ||||
 Heart rate | 90.0 (80.5–97.0) | 88.0 (80.0–100.0) | 93.0 (88.3–97.0) | 0.574 |
 Respiratory rate | 21.0 (18.0–25.0) | 21.0 (18.0–25.0) | 19.0 (17.0–21.5) | 0.095 |
 SpO2, % | 97.0 (95.0–99.0) | 97.0 (95.0–99.0) | 98.0 (94.8–100.0) | 0.353 |
Arterial blood gas analysis pre-HFNC initiation | ||||
 pH | 7.44 (7.39–7.47) | 7.45 (7.39–7.47) | 7.42 (7.39–7.45) | 0.105 |
 PaO2 | 76.8 (68.6–84.7) | 73.3 (67.3–82.0) | 91.2 (79.4–103.6) | 0.088 |
 PF ratio | 243.3 (199.1–294.4) | 243.3 (196.9–291.0) | 252.8 (229.2–333.2) | 0.378 |
 PaCO2, mmHg | 36.7 (33.0–41.6) | 36.5 (32.0–41.6) | 37.5 (35.5–41.5) | 0.272 |
 Bicarbonate, mmol/L | 23.0 (21.0–27.1) | 23.0 (20.9–27.5) | 23.0 (21.0–26.8) | 0.866 |
HFNC initiation settings and outcomes | ||||
 Initial HFNC flow | 60.0 (55.0–60.0) | 60.0 (50.0–60.0) | 60.0 (57.5–60.0) | 0.691 |
 Initial FiO2 set on HFNC | 40.0 (30.0–45.0) | 40.0 (30.0–40.0) | 42.5 (40.0–50.0) | 0.012* |
 Duration of HFNC in hours | 20.5 (12.1–27.2) | 21.4 (13.6–27.3) | 15.0 (7.8–26.6) | 0.179 |
 ICU stay duration | 7.0 (5.0–13.0) | 7.0 (5.0–13.0) | 9.5 (6.0–14.3) | 0.284 |
 ICU mortality | 5 (6.2%) | 1 (1.5%) | 4 (28.6%) | 0.046* |
 Hospital stay duration | 28.0 (13.0–38.0) | 30.0 (14.0–38.0) | 17.0 (9.5–34.3) | 0.103 |
 Hospital mortality | 9 (11.1%) | 4 (6.0%) | 5 (35.7%) | 0.024 |