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

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.

Study Overview

• Status: Recruiting
• Conditions: Mechanical Ventilation
• Intervention / Treatment: Procedure: Inspiratory support level

• Study Type: Interventional
• Enrollment (Anticipated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jian-Xin Zhou, MD; Phone Number: 8610 59978019; Email: zhoujx.cn@icloud.com

Study Locations

• China
  • Beijing
    • Beijing, Beijing, China, 100070
      • Recruiting
      • Beijing Tiantan Hospital
      • Contact: Yan-Lin Yang, MD
    • Beijing, Beijing, China, 100029
      • Recruiting
      • China-Japan Friendship Hospital
      • Contact: De-Jing Song, BS

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Inspiratory support level with PMI equal to -2; PMI represents the difference between plateau airway pressure and peak airway pressure (plateau - peak) during an end-inspiratory airway occlusion.	Procedure: Inspiratory support level; Inspiratory support is the pressure delivered by the ventilator during pressure support ventilation.
Experimental: Inspiratory support level with PMI equal to 0; PMI represents the difference between plateau airway pressure and peak airway pressure (plateau - peak) during an end-inspiratory airway occlusion.	Procedure: Inspiratory support level; Inspiratory support is the pressure delivered by the ventilator during pressure support ventilation.
Experimental: Inspiratory support level with PMI equal to +2; PMI represents the difference between plateau airway pressure and peak airway pressure (plateau - peak) during an end-inspiratory airway occlusion.	Procedure: Inspiratory support level; Inspiratory support is the pressure delivered by the ventilator during pressure support ventilation.

What is the study measuring?

Primary Outcome Measures

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

Secondary Outcome Measures

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

Collaborators and Investigators

• Sponsor: Capital Medical University

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2021
• Primary Completion (Anticipated): January 1, 2022
• Study Completion (Anticipated): February 1, 2022

Study Registration Dates

• First Submitted: August 17, 2021
• First Submitted That Met QC Criteria: August 23, 2021
• First Posted (Actual): August 30, 2021

Study Record Updates

• Last Update Posted (Actual): January 11, 2022
• Last Update Submitted That Met QC Criteria: December 26, 2021
• Last Verified: December 1, 2021

More Information

Terms related to this study

• Keywords: mechanical ventilation; lung injury; work of breathing; pressure support; inspiratory effort
• Other Study ID Numbers: KY2021-012-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No