Abstract
Background: Despite benefits, e.g. preserved diaphragm activity, appropriate timing for initiation of assisted ventilation in ARDS is subject of debate. Moreover, in patients with high respiratory drive the transition from controlled to assisted modes may be delayed in the presence of high tidal volume (VT) and high transpulmonary pressure (PL). Inducing respiratory muscle weakness with low dose neuromuscular blocking agents (NMBAs) might reduce VT and PL.
Aim: To evaluate whether partial neuromuscular blockade facilitates lung-protective assisted mechanical ventilation.
Methods: Ten ARDS patients with VT>8 mL/kg PBW were studied. First, the effects of different assisted modes were evaluated (PSV low/high and NAVA). Second, rocuronium was titrated to target VT=6 mL/kg. Third, patients were ventilated 1 hr with PSV and NAVA under continuous NMBA infusion. PL, VT, diaphragm activity (EAdi), mean arterial pressure (MAP), and heart rate were measured.
Results: NMBA titration resulted in a strong decline of VT, PL and EAdi (Fig 1). During titration pH (7.42±0.02 to 7.35±0.02; P<0.0001) decreased, and MAP (84±6 to 99±6 mmHg; P=0.0004) and heart rate (83±7 to 93±8 beats/min; P=0.0004) increased.
Conclusions: Partial neuromuscular blockade facilitates lung protective assisted ventilation, while preserving diaphragm activity. These findings suggest a new strategy for patients recovering from ARDS with high respiratory drive.
- ARDS (Acute Respiratory Distress Syndrome)
- Mechanical ventilation - interactions and complications
- Respiratory muscle
- Copyright ©the authors 2016
