Recruiting

Exercise

Sponsor:

Unity Health Toronto

Code:

NCT04004104

Conditions

Hepatopulmonary Syndrome

Eligibility Criteria

Sex: All

Age: 0+

Healthy Volunteers: Not accepted

Interventions

Upright Exercise

Supine Exercise

Study Details

Brief summary:

Hepatopulmonary syndrome (HPS) is a rare condition that presents in about a quarter of patients with liver cirrhosis. In addition, a small subset of these HPS patients also have orthodeoxia, defined as a drop in oxygen levels when they are sitting up (upright), as opposed to lying flat (supine). At present, there is little known about this condition. Patients diagnosed with HPS and orthodeoxia experience reduced ability to exercise, especially when upright. While standard cardiopulmonary exercise is routinely performed in the sitting position, there are machines that enable candidates to exercise in the supine position. This is especially relevant in patients with severe HPS, with clinically significant orthodeoxia, where conventional upright exercise is difficult. Currently there is a gap in the literature regarding the efficacy of supine exercise compared to upright exercise in these patients. Due to their improvement in dyspnea when lying supine, it is predicted that these patients will be able to exercise for a greater length of time and have increased exercise capacity, which can be projected to improve outcomes pre- and post-transplant.

Overall, HPS patients tend to experience hypoxemia and exercise limitation. Exercise limitation impacts quality of life, incidence and severity of comorbid conditions, and in those who are liver transplant candidates, low exercise tolerance deleteriously impacts transplant outcomes. Accordingly, a strategy that enables patients to exercise more often and/or for longer periods would offer direct benefits to patients with HPS, and if employed as part of an exercise program, could also improve exercise capacity, and thus, liver transplant outcomes.

The purpose of this study is to investigate the effect of supine, compared to upright position on exercise in patients with HPS and orthodeoxia. We hypothesize that these patients will be able to exercise for longer in the supine compared to the upright position, given improved oxygen levels when supine.

Conditions

Hepatopulmonary Syndrome

Study ID

NCT04004104

Start date

Jul 24, 2019

Status verified date

May, 2023

Completion date

Aug 31, 2024

Anticipated

Primary completion date

Dec 1, 2023

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 0+

Healthy Volunteers: Not accepted

Inclusion Criteria:

1. Diagnosis of moderate HPS (defined by liver disease, hypoxemia \[PaO2 < 80 mmHg and AaDo2 (alveolar-arterial PO2 difference) ≥ 15 mmHg or ≥ 20 mmHg if age > 64 years\] and IPVD (intrapulmonary vasodilatations) as shown by contrast echocardiography\])
2. Presence of orthodeoxia (PaO2 decrease by >4 mmHg when patient moves from supine to upright position).

Exclusion Criteria:

1. Pulmonary hypertension (echocardiographic estimated right ventricular systolic pressure >/=50 mmHg and/or right heart catheterization mean pulmonary artery pressure >25 mmHg with pulmonary capillary wedge pressure </= 15 mmHg);
2. Significant obstructive ventilatory impairment (FEV1/FVC ratio < 0.65) (FEV=forced expiratory volume in 1 second; FVC=forced vital capacity)
3. Known significant coronary artery disease;
4. Significant neurologic, orthopedic or rheumatological disorders preventing the use of a cycle ergometer;
5. Other absolute contraindications to submaximal tests (uncontrolled cardiac arrhythmia with hemodynamic compromise, symptomatic severe aortic stenosis, decompensated heart failure and acute cardiopulmonary illness);
6. Moderate or severe ascites.

Study Design

Enrollment

10 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Supportive Care

Interventions and Outcome Measures

Arms

active comparator: Control - Upright Exercise

Participants will perform upright exercise on a cycle ergometer. The opposite test will be completed within 4 weeks.

experimental: Intervention - Supine Exercise

Participants will perform supine exercise on a cycle ergometer. The opposite test will be completed within 4 weeks.

Interventions

Upright Exercise

Exercise is generally performed in the upright position.

Supine Exercise

Since HPS patients with orthodeoxia experience an improvement in their symptoms and oxygen levels when supine, the intervention will involve them performing exercise in the supine position.

Primary outcome measure

  • Stopping time (tLIM) [ Time Frame: 12 months ]

Central Contacts and Locations

Central contacts

Samir Gupta, MD, MSc

(416) 864-6060GuptaS@smh.ca

Locations

St. Michael's Hospital

Recruiting

Toronto, Ontario, Canada, M5B 1W8

Contacts

Samir Gupta, MD, MSc

(416) 864-6060guptas@smh.ca

Principal Investigator:

Samir Gupta, MD, MSc

More Information

Sponsor

Unity Health Toronto

Last update posted

May 10, 2023

Last verified

May, 2023

Keywords

  • Supine Exercise
  • Orthodeoxia

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Unity Health Toronto on 2023-05-10.