From the Guidelines
IPAP settings should be greater than 20, and sometimes up to 30, in patients with severe kyphoscoliosis, and greater than 30 in patients with OHS.
IPAP Settings
- In patients with Obesity Hypoventilation Syndrome (OHS), high inspiratory positive airway pressure (IPAP) settings are commonly required, with IPAP > 30 and EPAP > 8 1.
- In patients with severe kyphoscoliosis, an IPAP > 20, and sometimes up to 30, may be required due to the high impedance to inflation 1.
- In patients with Neuromuscular Disease (NMD), a low degree of pressure support (eg, a pressure difference of 8–12 cm) is needed, unless there is significant skeletal deformity 1.
- The inspiratory/expiratory time (IE) ratio for the backup rate (or PCV) should initially be set at 1:1 to allow an adequate time for inspiration 1.
Considerations
- Bulbar dysfunction renders effective NIV more difficult to achieve, requires a higher EPAP to overcome upper airway obstruction, and needs special attention to aid cough and the clearing of upper and lower airways 1.
- Clinical experience in providing NIV is needed to best titrate the EPAP 1.
- A modest increase in the domiciliary ventilator settings is advised in the case of home mechanical ventilation patients being admitted with AHRF 1.
From the Research
IPAP Settings
- The recommended minimum starting IPAP should be 8 cm H2O 2, 3
- The recommended maximum IPAP should be 30 cm H2O for patients > or = 12 years and 20 cm H2O for patients < 12 years 2, 3
- IPAP and/or EPAP should be increased until the following obstructive respiratory events are eliminated: apneas, hypopneas, respiratory effort-related arousals, and snoring 2, 3
- The pressure support (PS) should be increased every 5 minutes if the tidal volume is low (< 6 to 8 mL/kg) 2
- The PS should be increased if the arterial PCO2 remains 10 mm Hg or more above the PCO2 goal at the current settings for 10 minutes or more 2
Adjustment of IPAP
- IPAP should be increased as described in AASM Clinical Guidelines for the Manual Titration of Positive Airway Pressure in Patients with Obstructive Sleep Apnea until obstructive respiratory events are eliminated 2
- The IPAP may be increased if respiratory muscle rest has not been achieved by NPPV treatment at the current settings for 10 minutes or more 2
- The IPAP may be increased if the SpO2 remains below 90% for 5 minutes or more and tidal volume is low (< 6 to 8 mL/kg) 2
Clinical Applications
- In patients with COPD, higher IPAP levels were associated with an increased use of full-face masks (FFMs) 4
- In patients with obesity hypoventilation syndrome and obstructive sleep apnea syndrome, auto-trilevel positive airway pressure ventilation was more effective than conventional fixed bilevel positive airway pressure ventilation in correcting hypercapnia and improving sleep quality 5
- Operator-dependent factors, such as inappropriate indication, lack of adequate titration, and overlooked contraindication, can contribute to failure of non-invasive positive pressure ventilation (NIPPV) 6