Incidence, Risk Factors and Outcomes of Diaphragm Dysfunction After Lung Transplantation

Study Overview
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Brief Summary
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The study is designed to characterize the changes in diaphragm function after lung transplantation.

Detailed Description
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Diaphragm dysfunction (DD) is a well-known complication after lung transplantation. Patients with an injured and dysfunctional diaphragm have greater difficulty weaning from mechanical ventilation post-transplant - they become too weak to breathe. However, little is known about the pre-transplant predictive factors associated with diaphragm dysfunction . We have developed a new technique employing beside ultrasound to measure diaphragm thickness. This allows us to observe changes in diaphragm muscle structure and function. The goal of the study is to determine whether pre-transplant diaphragm thickness and function are associated with diaphragmatic dysfunction after lung transplantation. This will help us to confirm the best way to avoid diaphragm injury and to understanding the meaning of diaphragm ultrasound images.

Official Title
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Incidence, Risk Factors and Outcomes of Diaphragm Dysfunction After Lung Transplantation

Conditions
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Diaphragm Injury, Lung Transplant; Complications, Mechanical, Respiratory Failure, Mechanical Ventilation Complication

Intervention / Treatment
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* Diagnostic Test: Ultrasound
* Diagnostic Test: Respiratory function measurements


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients greater than 18 years of age Listed for lung transplantation Exclusion Criteria: Known diagnosis of chronic neuromuscular disease Relisting for transplantation Bridging to lung transplantation with respiratory support

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Ultrasound|Sonographic measurements (diaphragm, abdominal muscle, and quadriceps thickness) will be acquired when listed for lung transplantation. Sonographic measurements will be recorded on a daily basis for up to 1 week after transplantation (while the patient remains intubated).|
|Diagnostic Test: Respiratory function measurements|Maximal expiratory pressure (MEP) and maximal inspiratory pressure (MIP) will be acquired after listing for lung transplantation. After transplant, MIP will be recorded once patients are eligible for a trial of spontaneous breathing and weekly thereafter. MEP will also be recorded at ICU discharge.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of diaphragm dysfunction at the first spontaneous breathing trial and at ICU discharge after lung transplantation | Diaphragm ultrasound will be used to visualize diaphragm dysfunction (maximal thickening fraction <20%) | First spontaneous breathing trial, an average of 1 to 7 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pre-transplant diaphragm thickness and function compared to post-transplant diaphragm dysfunction | Diaphragm thickness and function documented on ultrasound will be assessed | 1 day |