Effects of Propofol on Patient-Ventilator Synchrony and Interaction During Pressure Support Ventilation and Neurally Adjusted Ventilatory Assist*

Abstract

In pressure support ventilation, deep propofol sedation increased asynchronies, while light sedation did not. Propofol reduced the respiratory drive, while breathing timing was not significantly affected. Gas exchange and breathing pattern were also influenced by propofol infusion to an extent that varied with the depth of sedation and the mode of ventilation.

Esophageal and transpulmonary pressure in the clinical setting: meaning, usefulness and perspectives

“…These two calibration approaches to compare absolute values of a patient's effort obtained from EAdi require further validation. It is also important to note that EAdi amplitude can be influenced by other factors, such as sedation [75] and clinical evolution [74].…”

“…EAdi can also be used to accurately monitor patientventilator synchrony [55,75,76]. Finally, as the EAdi value recorded at the onset of the inspiratory flow (autoEAdi) is tightly correlated with the patient's auto-PEEP, as measured by Pes [77], EAdi can also be used to estimate auto-PEEP.…”

Is sedation safe and beneficial in patients receiving NIV? No

“…By adopting EAdi monitoring, Vaschetto et al [18] showed in intubated patients that propofol significantly interferes with patient-ventilator synchrony in pressure support ventilation (PSV) at doses producing deep sedation. Both during PSV and neurally adjusted ventilator assistance (NAVA), propofol reduced neural drive and effort, while not significantly affecting respiratory timing.…”

Neurally adjusted ventilatory assist

“…As depicted in Fig. 2, during partial ventilatory assistance, EAdi is influenced by multiple factors, including the amount of assistance and sedation [4,5 && ]. With NAVA and PAV, the mechanical support delivered by the ventilator is directly (NAVA) or indirectly (PAV) driven and regulated by the effort exerted by the respiratory muscles [2]; this does not occur with the other assisted modes, in which the mechanical support is not affected by the patient's drive and effort.…”