Respiratory, Limb Muscle Properties, and Physical Performance in Adult Lung Transplant Recipients

Purpose

The goal of this observational study is to evaluate respiratory and limb muscle properties in adults awaiting lung transplantation and determine how these measures relate to physical performance, symptoms, and recovery after transplantation. Respiratory and limb muscle weakness may contribute to impaired mobility, frailty, and delayed postoperative recovery, but their specific role in lung transplant candidates is not well understood. Participants will undergo muscle ultrasound imaging at weekly basis, respiratory and limb strength testing, physical performance assessments, and symptom questionnaires once before and after transplantation. Researchers will also collect information from medical records regarding intensive care unit stay, hospital length of stay, rehabilitation participation, and postoperative recovery outcomes.

Conditions

  • Lung Transplantation
  • End Stage Lung Disease

Eligibility

Eligible Ages
Over 18 Years
Eligible Sex
All
Accepts Healthy Volunteers
No

Inclusion Criteria

  • 18 years or older. - Hospitalized as potential candidates for single- or bilateral-lung transplant surgery. - Hemodynamically stable for out-of-bed mobilization

Exclusion Criteria

  • Baseline cognitive impairment - History of previous solid organ transplantation or thoracic surgery - Existing phrenic nerve lesion - Lower limb amputation or fracture - External fixators or open wounds of the lower extremities - Diagnosed neuromuscular disorder. - Morbid obesity (body mass index >45 kg/m²). - Any other medical condition that, in the opinion of the investigators, would make participation unsuitable.

Study Design

Phase
Study Type
Observational [Patient Registry]
Observational Model
Cohort
Time Perspective
Prospective

Arm Groups

ArmDescriptionAssigned Intervention
Adult Lung Transplant Candidates adults enrolled for in-hospital evaluation for lung transplant and listed for surgery who undergo serial assessments of respiratory and limb muscle properties before transplantation and during the early postoperative period. Assessments include ultrasound imaging, respiratory and limb strength testing, physical performance measures, patient-reported outcomes, and collection of clinical outcomes from the medical record.
  • Diagnostic Test: Respiratory and Limb Muscle Assessment
    Participants undergo serial assessments of respiratory and limb muscle structure and function before and after lung transplantation. Assessments include ultrasound imaging of the diaphragm, rectus abdominis, and quadriceps muscles; respiratory muscle strength testing; handgrip strength testing; knee extension strength testing; physical performance measures; and patient-reported outcome questionnaires.

Recruiting Locations

UF Health Shands Medical Center
Gainesville, Florida 32608
Contact:
Mindaugas Rackauskas, MD, PhD
(352) 265-5470
mindaugas.Rackauskas@surgery.ufl.edu

More Details

Status
Recruiting
Sponsor
University of Florida

Study Contact

Barbara K Smith, PhD, PT
352-294-5315
bksmith@ufl.edu

Detailed Description

Respiratory and peripheral muscle dysfunction are common in individuals with advanced lung disease awaiting lung transplantation. Muscle weakness, atrophy, and impaired contractile function may contribute to reduced physical performance, frailty, symptom burden, and delayed recovery after transplantation. Although physical function tests provide an overall assessment of performance, they provide limited information regarding specifics of respiratory and limb muscle impairments. Ultrasound imaging is a noninvasive and reliable method to evaluate muscle structure, quality, and contractile function and has been associated with clinical outcomes in several critically ill populations, including prolonged mechanical ventilation, longer intensive care unit (ICU) and hospital stays, and increased morbidity. The purpose of this study is to characterize respiratory and limb muscle properties before and after lung transplantation and determine how these measures relate to physical performance, patient-reported outcomes, and postoperative recovery. Respiratory muscle function will be assessed using maximal respiratory pressure testing and ultrasound evaluation of the diaphragm and abdominal muscles. Limb muscle function will be assessed using ultrasound imaging and strength testing of the quadriceps muscles. Physical performance, frailty, dyspnea, pain, fatigue, anxiety, and ICU/hospital-related outcomes will also be evaluated. The central hypothesis of this study is that respiratory and limb muscle weakness, atrophy, and impaired contractile function are associated with poorer physical performance, greater symptom burden, and delayed postoperative recovery after lung transplantation. To test this hypothesis, a prospective observational study of adult lung transplant candidates will be conducted from their hospital admission to their post-operative day 14. Participants will undergo serial ultrasound imaging assessments before transplantation and during the early postoperative period along with symptom questionnaires; while respiratory and limb strength testing, functional assessments, symptom questionnaires will be collected on the first and last day of research visit. Collection of ICU and hospital outcomes will occur from the electronic medical record. The central hypothesis will be evaluated through the following aims: Aim 1: Evaluate relationships between respiratory strength and ultrasound measurements of contractile dysfunction in candidates awaiting lung transplant. Aim 2: Characterize the associations between respiratory and limb muscle properties (atrophy, strength), physical performance, and patient-centered outcomes (dyspnea, frailty, pain, fatigue, and anxiety) in pre-lung transplant candidates. Aim 3: Identify the influence of preoperative respiratory and quadriceps contractile function on the early postoperative mobility progression in lung transplant recipients Aim 4: Determine relationships between postoperative diaphragm dysfunction and functional status at hospital discharge