Table 2 The risk factors and suggestions for the management of NIV failure based on timing

Immediate

1. Weak cough reflex and/or excessive secretions

1a. Manual or mechanic chest physiotherapeutic techniques; b. Early fiberoptic bronchoscopy.

[14–24]

2. Hypercapnic encephalopathy and coma

2a. Set a back-up rate ~ 15 b/min and/or use PCV; b. Decrease the F_İO2 level.

[16, 25–27]

3. Intolerance and psychomotor agitation

3. Judicious sedation

[14, 28–32]

4. “Fighting with the machine”: Patient-ventilator asynchrony

4a. Closely monitor ventilator waveforms; b. Judicious sedation; c. Use a ventilator with an NIV platform; d. Change ventilatory parameters; e. Minimize air-leaks.

[33, 34]

Early Hypoxemic ARF

1. Baseline ABG and inability to correct gas exchange (P/F < 150)*

[4] ([36, 38, 39, 42]*])

2. Baseline severity scores (SAPS II >35)*

[1, 5, 36]*,[37]*,[39, 43, 49]*-[51]

3. The presence of ARDS/pneumonia/sepsis/multiorgan failure (OR: 4-28)*

[36]*,[40, 41, 49, 50, 52]*-[54]

4. Increased respiratory rate (>25 breaths/min)*

[51]*,[53, 55]*,[56]

5. Miscellaneous: Delay between admission and NIV use, Number of fiberoptic bronchoscopes performed, Duration of NIV use, Increase in radiographic infiltrates within the first 24 hours, Causal diagnosis (as ‘de novo’)

[1, 36, 43, 51, 53, 57]

Hypercapnic ARF

1. Baseline ABG and inability to correct gas exchange (pH < 7.25)*

[3]*,[6, 12, 14, 58–60, 62, 63]

2. Increased severity of disease

[3, 12, 14, 15, 59, 62, 64]

3. Increased respiratory rate (>35 breaths/min, OR for baseline and after 2 hours of NIV: 2.66 and 4.95)*

[3]*,[6, 15, 58, 59]

4. Mixed indices:

 GCS, APACHE II score, respiratory rate and pH

[3]

 Respiratory rate, random glucose level and APACHE II

[66]

 Anemia and World Health Organization Performance Status (WHO-PS)

[67]

5. Miscellaneous: Poor nutritional status, Increased heart rate, Higher baseline C-reactive protein/white blood cell count, Lower serum potassium, Airway colonization by non-fermenting gram-negative bacilli

[63, 68, 69]

Late

1. Sleep disturbance

1a. Improve quality of sleep; b. Avoid excessive noise and light in the unit

[70]

2. Functional limitation

[2]

3. Possible initial improvement in pH

3a. Close and continuous monitoring of vital parameters; b. Repeat frequent ABGs during NIV, even when gas exchange reach a satisfactory value

[2, 64]

4. Hyperglycemia

4. Check glucose levels

[2]