Initial equipment settings and monitoring for acute noninvasive ventilation

Suggested initial equipment settings and monitoring for acute noninvasive ventilation are listed in Suggested initial equipment settings and monitoring for acute noninvasive ventilation.

Choose a suitable mask interface (oro-nasal, nasal, total face or helmet).

Once the machine is attached and switched on, hold the mask to the patient’s face to familiarise them with it. After a few minutes, secure the mask. Do not overtighten the mask because breakdown of the skin at the mask contact point can occur very rapidly. Show the patient how to remove the mask and how to ask for help if needed.

Figure 1. Suggested initial equipment settings and monitoring for acute noninvasive ventilation

Suggested initial equipment settings for acute noninvasive ventilation:

  • Suggested initial settings for BPAP (eg in COPD) are IPAP 10 to 12 cmH2O and EPAP 4 to 6 cmH2O [NB1].
  • If a spontaneous/time mode ventilator is used, set this with a backup rate of 15 breaths per minute and I:E ratio of 1:3.
  • Set triggers at maximum sensitivity.
  • Suggested initial settings for CPAP (eg in acute pulmonary oedema) are 5 to 15 cmH2O (approximately 10% of body weight in kilogram).

Suggested monitoring for acute noninvasive ventilation:

  • Monitor SpO2 continuously.
  • Reassess the patient within a few minutes and adjust ventilator settings and oxygen therapy to target oxygen saturation levels; see also Ventilator adjustment for acute noninvasive ventilation and oxygen therapy.
  • Repeat clinical assessment and arterial blood gases in 1 hour; if there is no improvement, review and adjust ventilator settings (see Ventilator adjustment for acute noninvasive ventilation and oxygen therapy). Observations should include respiratory rate, heart rate, blood pressure, level of consciousness, pain score, patient comfort, skin integrity at mask contact points, chest wall movement, ventilator synchrony and accessory muscle use.
  • Repeat clinical assessment and arterial blood gases after 4 hours or as clinically indicated. If there is improvement, consider monitoring using venous blood gases if access to arterial blood gases is difficult [NB2].
  • Regularly review management plan (at least every 24 hours and with a change in patient’s condition) and update as required.
Note:

BPAP = bilevel positive airway pressure; COPD = chronic obstructive pulmonary disease; CPAP = continuous positive airway pressure; I:E ratio = inspiratory to expiratory ratio; IPAP = inspiratory positive airway pressure; EPAP = expiratory positive airway pressure; SpO2 = oxygen saturation measured by pulse oximetry

NB1: IPAP provides pressure support for inspiration, which increases alveolar ventilation and assists in reducing carbon dioxide. EPAP improves aeration of the lungs.

NB2: Venous blood gas values do not correlate directly with arterial blood gas values. See Venous blood gas analysis for more information.