Pressure Support Ventilation During Mechanical Ventilation
Pressure Support Ventilation During Mechanical Ventilation
In this observational cohort study of physician-led weaning practice in a large university ICU, PSV was initiated early in the course of MV, even in patients with high levels of sickness severity and with the majority not meeting conventional criteria for weaning. Despite this, PSV was well tolerated in a large proportion of the cohort with active weaning of pressure support and a significant rate of early extubation achieved. Furthermore, the conventional screening criteria (as interpreted and applied in this study) did not predict PSV failure. Acidaemia is associated with failure to sustain PSV and this should be heeded by clinicians before weaning from the ventilator and may be considered in future weaning trials and guidelines. Failure to sustain a PSV trial for 24 h may be considered as a clinical indicator of patients who are at increased risk of prolonged MV and mortality, and the predictive test characteristics of this as a clinical tool would be important to determine. Early transition to PSV appears safe and effective in the majority of patients. Rigorous application of strict screening criteria, often reported in the literature, may delay initiation of weaning in a cohort of patients, with clinical and healthcare utilisation implications.
Conclusion
In this observational cohort study of physician-led weaning practice in a large university ICU, PSV was initiated early in the course of MV, even in patients with high levels of sickness severity and with the majority not meeting conventional criteria for weaning. Despite this, PSV was well tolerated in a large proportion of the cohort with active weaning of pressure support and a significant rate of early extubation achieved. Furthermore, the conventional screening criteria (as interpreted and applied in this study) did not predict PSV failure. Acidaemia is associated with failure to sustain PSV and this should be heeded by clinicians before weaning from the ventilator and may be considered in future weaning trials and guidelines. Failure to sustain a PSV trial for 24 h may be considered as a clinical indicator of patients who are at increased risk of prolonged MV and mortality, and the predictive test characteristics of this as a clinical tool would be important to determine. Early transition to PSV appears safe and effective in the majority of patients. Rigorous application of strict screening criteria, often reported in the literature, may delay initiation of weaning in a cohort of patients, with clinical and healthcare utilisation implications.