Use of Pressure Muscle Index to Avoid Over-assistance During Pressure Support Ventilation

Not Applicable

• Conditions: Mechanical Ventilation
• Interventions: Procedure: Inspiratory support level

• Registration Number: NCT05026463
• Lead Sponsor: Capital Medical University

Brief Summary

Pressure support ventilation (PSV) is the most commonly used mode in mechanical ventilated patients. Studies have shown that over-assistance was prevalent in patients undergoing PSV. Up to now, no reliable method has been recommended to select an "optimal" inspiratory support level. Pressure muscle index (PMI) was introduced recently to evaluate the degree of spontaneous breathing effort. We hypothesize that PMI might be used as an indicator for over-assistance during PSV. In this randomized crossover study, inspiratory support is set at three levels according to negative, positive and zero PMI. Inspiratory effort, work of breathing, and respiratory mechanics are compared among the three inspiratory pressure support levels.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2021-08-17
• Study First Submitted QC: 2021-08-23
• Study First Posted: 2021-08-30
• Study Start: 2021-09-01
• Status Verified: 2021-12
• Last Update Submitted: 2021-12-26
• Primary Completion: 2022-01
• Last Update Posted: 2022-01-11
• Study Completion: 2022-02

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 20

Inclusion Criteria

• Mechanical ventilated patients within 48 hours after the transition from a controlled mode to PSV

Exclusion Criteria

• History of neuromuscular disease
• History of diaphragm dysfunction and surgery
• History of esophageal, gastric or lung surgery
• Decreased level of consciousness
• Central respiratory drive dysfunction
• Considered withholding of life support

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Inspiratory support level with PMI equal to -2	Inspiratory support level	PMI represents the difference between plateau airway pressure and peak airway pressure (plateau - peak) during an end-inspiratory airway occlusion.
Inspiratory support level with PMI equal to 0	Inspiratory support level	PMI represents the difference between plateau airway pressure and peak airway pressure (plateau - peak) during an end-inspiratory airway occlusion.
Inspiratory support level with PMI equal to +2	Inspiratory support level	PMI represents the difference between plateau airway pressure and peak airway pressure (plateau - peak) during an end-inspiratory airway occlusion.

Primary Outcome Measures

Name	Time	Method
Inspiratory effort	30 minutes	Inspiratory effort is measured as pressure generated by inspiratory muscles using esophageal pressure monitoring.
Work of breathing	30 minutes	Work of breathing is measured by the Campbell diagram and pressure-time-product using esophageal pressure monitoring.

Secondary Outcome Measures

Name	Time	Method
Partial pressure of carbon dioxide in arterial blood (mmHg)	30 minutes	Partial pressure of carbon dioxide in arterial blood is obtained by blood gas analysis.
Tidal volume (ml)	30 minutes	Tidal volume is obtained by intergation of flow-time tracing.
Respiratory system compliance (ml/cmH2O)	30 minutes	Respiratory system compliance is calculated as the ratio between tidal volume and driving pressure.
Respiratory rate (breaths/min)	30 minutes	Respiratory rate calculation includes ineffective trigger.
Rapid shallow breathing index	30 minutes	Rapid shallow breathing index is calculated as the ratio between respiratory rate and tidal volume.
The use of accessory respiratory muscle	30 minutes	The use of accessory respiratory muscle is observed at the bedside.
Partial pressure of oxygen in arterial blood (mmHg)	Partial pressure of oxygen in arterial blood	Partial pressure of oxygen in arterial blood is obtained by blood gas analysis.

Trial Locations

Locations (2)

China-Japan Friendship Hospital; 🇨🇳 Beijing, Beijing, China

Beijing Tiantan Hospital; 🇨🇳 Beijing, Beijing, China