Maintaining ventilatory settings in seven home ventilators during leaks

Using home ventilators (HV) may be an alternative for non-invasive ventilation in intensive care patients with respiratory failure. Air leaks are frequent in such patients and may be deleterious for the efficacy of ventilation. Few data are available about performances of HV. We analyse the adequacy of ventilatory settings in seven HV during ventilation with increasing leaks on respiratory system.

Study of seven HV on testing bench (SODEREL^®): 1:Hélia^® (SAIME); 2:Respicaire CV^® (DRAGER); 3:O'Nyx^® + (NELLCOR PB); 4:VPAP2 ST^® (SULLIVAN); 5:PV102 (BREAS); 6:Synchrony (RESPIRONICS); 7:Neftis (TAEMA).

Settings

Pep: 6 cm, PS: 15 cm, RR: 12/min, minimal slope, Expiratory Trigger minimal, Inspiratory Trigger maximal (ITmax) and minimal (ITmin).

Three periods have been studied: A:no additional air leak, B:one and C:two calibrated leaks (4 mm diameter each).

Parameters analysed

RR with ITmin, Pep and Paw with ITmax, iFmax, eFmax, I/E with Itmin.

Results

See Table overleaf.

Table

Conclusions

These seven HV are heterogeneous. Only two HV (4 and 6) are able to maintain the major parameters (RR, PEEP level and PS level). Two (1–3) are unable to maintain Pep level with maximum leaks and two (2–7) cannot even reach pressure support level.

Inspiratory time is systematically increased with inverse I/E in two cases. Auto triggering occurs with ITmin in three HV (1–2–5) and is independent of maintaining PEEP level.

It is probably important to consider performances of home ventilators before starting non-invasive ventilation in critically ill patients.