Effect of Diaphragm Stimulation During Surgery

Mechanical Ventilation Complication Clinical Trial

Official title: The Effect of Intermittent Hemidiaphragm Stimulation During Surgery on Mitochondrial Function, Single Fiber Contractile Force and Catabolic Pathways in Humans

Status Completed

Clinical Trial Summary

During major surgical procedures general anesthesia is used to make the patient unconscious. General anesthesia insures that the patient is unaware of any pain caused by surgery. General anesthesia also prevents the patient from moving to prevent any potential surgical error. At the same time general anesthesia makes it impossible for the patient to breathe. To help the patient breathe a breathing tube is placed into the patient's airway and connected to the mechanical ventilator. A mechanical ventilator is an artificial breathing pump, which delivers gas into a patient's airways.

The purpose of this research study is to determine if brief periods of diaphragm stimulation can prevent diaphragm problems caused by the use of mechanical ventilators and surgery. To answer this question the changes in the genes responsible for maintaining diaphragm function will be studied. A gene is the code present in each cell in your body and controls the behavior of that cell. In addition, the changes in the contractile properties of muscle fibers will be studied. The results from this study may help develop new treatments to prevent diaphragm weakness resulting from mechanical ventilation use.

Clinical Trial Description

Although mechanical ventilation (MV) is life-sustaining, it comes with a cost. MV dramatically reduces diaphragm contractility, induces ventilator-induced diaphragm dysfunction (VIDD) and sometimes leads to weaning failure. VIDD includes reduced mitochondrial respiration and increased oxidative stress, muscle fiber damage and decreased diaphragm force production.

In animal models, intermittent diaphragm contraction during MV support attenuates VIDD. However, there are only limited data addressing this problem in humans. Here, the study team propose to directly test the hypothesis that intermittent electrical stimulation (ES) of the human hemidiaphragm during prolonged cardiac surgeries with MV support prevents/attenuates VIDD in the active hemidiaphragm. Mitochondrial function is central to energy metabolism and skeletal muscle function in a chronically active muscle, such as the diaphragm. Although abnormal mitochondrial function is thought to precipitate VIDD in animal models, limited data are available concerning mitochondrial contributions to VIDD in humans. Of even greater importance, there are no interventions available to attenuate these defects in humans. Here, the study team will test the impact of an innovative experimental treatment, intermittent electrical stimulation (ES) of the hemidiaphragm during prolonged surgeries with MV, on mitochondrial function, single fiber contractile properties and catabolic muscle pathways in human diaphragm. Using a within-subjects experimental design, muscle samples from a stimulated hemidiaphragms will be compared with samples from the unstimulated hemidiaphragm. The study team will investigate mitochondrial dysfunction and oxidative stress during prolonged CTS/MV, and the potential of ES to attenuate or prevent VIDD. Next, the study team will investigate the effects of ES on single fiber contractile properties and Titin integrity. Finally, the study team will study the effect of ES on proteolytic pathways (caspase, calpain and ubiquitin-proteasome) and ribosomal RNA markers of decreased protein synthesis implicated in VIDD. ;

Related Conditions & MeSH terms

• Diaphragm Injury
• Mechanical Ventilation Complication

• NCT number: NCT03303040
• Study type: Interventional
• Source: University of Florida
• Status: Completed
• Phase: N/A
• Start date: February 14, 2018
• Completion date: December 31, 2023