NCT01666054

Comparison of Weaning on Pressure Support vs. Proportional Assist Ventilation: A Pilot Study

Is Respiratory Rate an Adequate Indicator of Respiratory Distress During Weaning? A Comparison of Weaning on Pressure Support vs. Proportional Assist Ventilation.

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 54 (actual)
• Sponsor: London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The study hypothesis is that reducing patient-ventilator asynchrony will reduce time required to wean from mechanical ventilation. The purpose of this pilot study is (1) to assess study feasibility in terms of recruitment, protocol adherence and efficacy of the intervention for reducing asynchrony, (2) to assess baseline rates of asynchrony and outcomes in the control arm in order to perform sample size calculations, if needed, for further, larger studies designed to detect differences in weaning time in specific, predefined populations and (3) to examine how often ineffective triggering (and therefore reduced ventilator respiratory rate) at higher levels of pressure support lead to a false conclusion that higher levels of support are needed to diminish respiratory distress.

Detailed description

Previous research has shown that approximately twenty-five percent of patients capable of triggering the ventilator in assisted modes have high rates of patient-ventilator asynchrony, and that such patients have a longer duration of mechanical ventilation. It is not known whether asynchrony is a cause of weaning failure or simply a marker of more severe respiratory failure. The most common type of asynchrony, ineffective triggering, may be both a marker of respiratory disease and a cause of delayed weaning. During ineffective triggering, the patient's inspiratory effort fails to trigger a ventilator breath, and thus the respiratory rate displayed on the ventilator underestimates the patient's true, intrinsic respiratory rate. Since ineffective triggering is more common at higher levels of pressure support than lower levels, an increase in respiratory rate during weaning of pressure support may indicate the development of respiratory distress or simply the abolition of ineffective triggering. Ineffective triggering may also cause delayed weaning because respiratory muscle energy is "wasted" on non-supported breaths. Proportional assist ventilation (PAV) is an FDA- and HPB-approved mode of ventilation in which the ventilator applies pressure in proportion to patient effort. Using PAV, patient-ventilator interaction may be optimized and ineffective triggering greatly reduced. Since the patient and ventilator respiratory rates are generally equivalent, a reduction in respiratory rate with increasing ventilatory support is less likely to be false positive indication of the need for greater assistance. In this study, patients with difficulty weaning from mechanical ventilation will be randomized to weaning with one of two weaning protocols: Proportional Assist Ventilation (PAV) weaning algorithm (intervention arm) vs. Pressure Support Ventilation (PSV) weaning algorithm (control arm).

Conditions

• Weaning From Mechanical Ventilation

Interventions

Type	Name	Description
OTHER	PSV	Pressure Support Ventilation will be used until patient is extubated
OTHER	PAV	Proportional Assist Ventilation will be used until patient is extubated.

Timeline

• Start date: 2009-03-01
• Primary completion: 2012-08-01
• Completion: 2013-07-01
• First posted: 2012-08-16
• Last updated: 2016-04-26

Locations

1 site across 1 country: Canada