Breath Synchronized Abdominal Muscle Stimulation to Facilitate Ventilator Weaning: a Pilot Study

Breath Synchronized Abdominal Muscle Stimulation to Facilitate Ventilator Weaning: a Pilot

The primary objective of this study is to determine whether neuromuscular electrical stimulation applied to the abdominal wall muscles in synchrony with exhalation can increase the strength of the respiratory muscles in prolonged mechanical ventilation patients.

Study Overview

• Status: Terminated
• Conditions: Respiration, Artificial; Ventilator Weaning; Electric Stimulation
• Intervention / Treatment: Device: Breath synchronized abdominal NMES; Device: Sham breath synchronized abdominal NMES

Detailed Description

In the U.S. over 500,000 patients have difficulty weaning from mechanical ventilation every year. These patients cost the health care system $16 billion annually and have an increased risk of medical complications and morbidity.

A major factor responsible for weaning failure is the imbalance between decreased respiratory muscle strength and excessive respiratory load. This study includes an investigational device that applies electrical stimulation to the abdominal muscles in synchrony with exhalation. This is hypothesized to improve the strength of the respiratory muscles. The long term goal of this project is to determine whether this approach can reduce the number of days taken for patients to wean from mechanical ventilation.

• Study Type: Interventional
• Enrollment (Actual): 2

Contacts and Locations

Study Locations

• United States
  • Kentucky
    • Louisville, Kentucky, United States, 40204
      • Kindred Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Patients who have been mechanically ventilated for at least fourteen days.
• Clinically stable: oxygen saturation > 90% with a fractional inspired oxygen ≤ 0.40, external positive end expiratory pressure ≤ 5 centimeters water, temperature ranging from 35.5 to 38.5 degrees celsius, no intravenous administration of vasoactive agents.

Exclusion Criteria:

• Patients in whom Neuromuscular Electrical Stimulation (NMES) does not elicit a palpable contraction of the abdominal muscles.
• Patients with broken or irritated skin on the abdominal wall
• Patients with a history of neuromuscular disease
• Body Mass Index (BMI) > 35 kg/m2
• Patients who are not medically stable
• Patients with a pacemaker
• Female patients who are pregnant
• Patients under the age of 18
• Patients who are expected to die within four weeks
• Patients who are unable to follow verbal instructions
• Patients with epilepsy
• Patients with an abdominal wall hernia
• Patients with anoxic encephalopathy
• Patients with history of, or active, substance abuse

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: VentFree Stimulation; Breath synchronized abdominal NMES	Device: Breath synchronized abdominal NMES; VentFree prototype (VF03) that delivers electrical stimulation pulses to the abdominal muscles during exhalation with a frequency of 30 Hz, a pulse width of 350 µs and 90% of the maximum current that the participant can tolerate. These stimulation parameters were selected to cause a tetanic (continuous) contraction of the abdominal muscles, without pain for the patient. Stimulation will be administered for 30 minutes 2 times per day, 5 days per week, for 6 weeks; or until the patient is weaned from mechanical ventilation.; Other Names: VentFree
Sham Comparator: Sham Stimulation; Sham breath synchronized abdominal NMES	Device: Sham breath synchronized abdominal NMES; Modified VentFree prototype (VF03) that delivers stimulation pulses to the abdominal muscles during exhalation with a frequency of 10 Hz, a pulse width of 100 µs and current set to 10 milliamp. These stimulation parameters were chosen to cause a twitch contraction of the abdominal wall muscles. Stimulation will be administered for 30 minutes, 2 times per day, 5 days per week, for 6 weeks; or until the patient is weaned from mechanical ventilation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Maximum Expiratory Pressure From Baseline to Extubation	Maximum expiratory pressure was measured from total lung capacity	Change from baseline to first extubation, an expected average of 4 weeks
Change in Maximum Inspiratory Pressure From Baseline to Extubation	Maximum inspiratory pressure was measured from end expiratory lung volume.	Change from baseline to first extubation, an expected average of 4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Thickness of the Transverse Abdominis Muscle From Baseline to Extubation	Thickness of transverse abdominis muscle as measured by ultrasound	Change from baseline to first extubation, an expected average of 4 weeks
Change in Thickness of the External Oblique Muscle From Baseline to Extubation	Thickness of the external oblique muscle as measured by ultrasound	Change from baseline to first extubation, an expected average of 4 weeks
Change in Thickness of the Internal Oblique Muscle From Baseline to Extubation	Thickness of the internal oblique muscle as measured by ultrasound	Change from baseline to first extubation, an expected average of 4 weeks
Thickness of the Rectus Abdominis Muscle	Thickness of the rectus abdominis muscle as measured by ultrasound	Change from baseline to first extubation, an expected average of 4 weeks
Thickness of the Diaphragm	Thickness of the diaphragm as measured by ultrasound	Change from baseline to first extubation, an expected average of 4 weeks
Weaning Success	Defined as free from ventilator support for more than 72 hours	The earlier of 6 weeks or first extubation, an expected average of 4 weeks
Number of Days Taken to Wean		The earlier of 6 weeks or first extubation, an expected average of 4 weeks
Change in Cough Peak Flow From Baseline to Extubation	Cough peak flow was measured from total lung capacity	Change from baseline to first extubation, an expected average of 4 weeks
Change in Spontaneous Tidal Volume From Baseline to Final Visit or First Extubation		Change from baseline to final study visit or first extubation, an expected average of 4 weeks
Change in Spontaneous Respiratory Rate From Baseline to Final Study Visit		Change from baseline to final study visit, an expected average of 4 weeks
Change in Spontaneous Minute Ventilation From Baseline to Final Study Visit		Change from baseline to final study visit, an expected average of 4 weeks
Maximum Sensation of Stimulation Experienced by Patient	Measured using the behavioral pain scale	Through study completion, an expected average of 4 weeks
Number of Adverse Events That Are Related to Treatment	This includes any adverse event that was graded as having a possible, probable or definite relationship to the study intervention.	Though study completion, an expected average of 4 weeks

Collaborators and Investigators

• Sponsor: Liberate Medical

Study record dates

Study Major Dates

• Study Start (Actual): February 22, 2017
• Primary Completion (Actual): April 6, 2017
• Study Completion (Actual): April 6, 2017

Study Registration Dates

• First Submitted: December 13, 2016
• First Submitted That Met QC Criteria: January 10, 2017
• First Posted (Estimate): January 12, 2017

Study Record Updates

• Last Update Posted (Actual): November 8, 2021
• Last Update Submitted That Met QC Criteria: October 11, 2021
• Last Verified: October 1, 2021

More Information

Terms related to this study

• Other Study ID Numbers: LM-KINDRED-01

Plan for Individual participant data (IPD)

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