Investigating the Anabolic Response to Resistance Exercise During Critical Illness

Not Applicable

Suspended

• Conditions: Muscle Loss; Critical Illness
• Interventions: Procedure: Resisted knee extension exercise; Drug: IV amino acids

• Registration Number: NCT05197231
• Lead Sponsor: Karolinska University Hospital

Brief Summary

ICU patients often suffer from rapid and severe muscle loss. It is not known if physical therapy can mitigate the muscle wasting associated with critical illness.

The aim of this study is to investigate the effects of resistance exercise on muscle protein turnover in ICU patients. The investigators hypothesize that resistance exercise, in addition to amino acid supplementation and routine physiotherapy, results in an improved lower limb muscle protein balance compared to amino acid supplementation and routine physiotherapy alone.

Detailed Description

Background

The debilitating impact of critical illness has been recognized for several decades. Disability related to intensive care is now described as a syndrome called ICU-acquired weakness (ICUAW). ICUAW affects up to 70% of ICU patients and is most common with higher illness severity. Patients that develop ICUAW require longer hospitalization and have a higher risk of death. Weakness also has significant long-term consequences, and is associated with significant health care costs, delayed return to work, and overall poor quality of life.

Preventing or reducing muscle atrophy is a potential way to counteract weakness. Critical illness is associated with a rapid loss of skeletal muscle. Studies in exercise physiology have demonstrated that resistance training and amino acid ingestion have synergistic effects on muscle protein synthesis in healthy subjects. It is therefore an appealing therapy to counteract muscle wasting in the ICU.

Despite several clinical trials, there is equipoise regarding the efficacy of exercise in improving physical function in-ICU or after discharge. These mixed signals are unsurprising given the heterogeneous causes of ICUAW. Only a few studies in this field assess muscle architecture or cellular signaling in response to training. However, the gold standard in determining the anabolic response to exercise is to directly measure the effect on protein synthesis and breakdown. To our knowledge there is still no published research using this methodology to assess the effects of exercise interventions in critically ill patients.

Aim and hypothesis

The overall aim of this project is to determine the anabolic response to resistance exercise during critical illness. The investigators hypothesize that resistance exercise, in addition to amino acid supplementation and routine physiotherapy, results in an improved muscle protein balance in ICU patients compared to amino acid supplementation and routine physiotherapy alone (primary outcome). The effect of the intervention on other parameters of muscle protein kinetics and within-group differences in protein kinetics before and after physiotherapy will be assessed as secondary outcome measures.

Study Timeline

• Study First Submitted: 2022-01-05
• Study First Submitted QC: 2022-01-05
• Study First Posted: 2022-01-19
• Study Start: 2022-12-25
• Status Verified: 2024-03
• Last Update Submitted: 2024-03-06
• Last Update Posted: 2024-03-07
• Primary Completion: 2027-12
• Study Completion: 2027-12

Recruitment & Eligibility

• Status: SUSPENDED
• Sex: All
• Target Recruitment: 24

Inclusion Criteria

1. Adult (≥18 years) patient admitted to the ICU of the study site.
2. Patient deemed suitable for active mobilization by the attending physician and physiotherapist.
3. Not expected to be discharged or transferred from the unit within 24 h of enrollment.
4. Functioning arterial catheter in situ.

Exclusion Criteria

1. Not able to provide informed consent.
2. Systemic anticoagulation with LMWH/UFH/DOAC in therapeutic dose range for deep vein thrombosis or pulmonary embolism, or dual antiplatelet therapy. If LMWH is administered twice daily, the patient is eligible for participation provided that vascular access is performed at nadir prior to the first daily dose.
3. Clinically significant inherited or acquired disorder of hemostasis.
4. Morbid obesity that interferes with femoral cannulation or doppler measurements.
5. Hemodynamic instability requiring ongoing volume resuscitation with crystalloid solutions or blood products.
6. Lower-limb amputee.
7. Lower-limb artherosclerotic disease with critical ischemia.
8. Metastatic cancer or active hematological malignancy.
9. Inherited disorder of amino acid metabolism.
10. Chronic muscle, neuromuscular and neurologic disease with prior documentation of clinically significant lower-limb involvement.
11. Pregnancy.
12. CAM-ICU screening positive for delirium.
13. Single organ failure not requiring invasive mechanical ventilation prior to enrollment.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
IV amino acids + standardized physiotherapy with lower limb resistance exercise.	Resisted knee extension exercise	Research subjects randomized to the intervention group will receive an infusion of IV amino acids during a session of protocolized physiotherapy that includes a knee extension resistance exercise targeting the thigh muscles. The supplemental amino acid infusion will continue up until 90 minutes after the subject has returned to bed rest.
IV amino acids + standardized physiotherapy with lower limb resistance exercise.	IV amino acids	Research subjects randomized to the intervention group will receive an infusion of IV amino acids during a session of protocolized physiotherapy that includes a knee extension resistance exercise targeting the thigh muscles. The supplemental amino acid infusion will continue up until 90 minutes after the subject has returned to bed rest.
IV amino acids + standardized physiotherapy.	IV amino acids	Research subjects randomized to the control group will receive an infusion of IV amino acids during a session of protocolized physiotherapy NOT including lower limb resistance exercise. The supplemental amino acid infusion will continue up until 90 minutes after the subject has returned to bed rest.

Primary Outcome Measures

Name	Time	Method
Between-group difference in change in lower limb protein balance	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The difference between the experimental and active comparator group in change in lower limb protein balance (nmol Phenylalanine/min) from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.

Secondary Outcome Measures

Name	Time	Method
Between-group difference in change in lower limb protein synthesis	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The difference between the experimental and active comparator group in change in lower limb protein synthesis (nmol Phenylalanine/min) from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb protein breakdown (active comparator group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb protein breakdown (nmol Phenylalanine/min) in the active comparator group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb protein balance (experimental group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb protein balance (nmol Phenylalanine/min) in the experimental group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb protein balance (active comparator group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb protein balance (nmol Phenylalanine/min) in the active comparator group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb protein breakdown (experimental group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb protein breakdown (nmol Phenylalanine/min) in the experimental group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Between-group difference in change in lower limb protein breakdown	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The difference between the experimental and active comparator group in change in lower limb protein breakdown (nmol Phenylalanine/min) from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Between-group difference in change in lower limb 3-methylhistidine rate of appearance	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The difference between the experimental and active comparator group in change in lower limb 3-methylhistidine rate of appearance (nmol 3-methylhistidine/min) from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb protein synthesis (experimental group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb protein synthesis (nmol Phenylalanine/min) in the experimental group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb protein synthesis (active comparator group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb protein synthesis (nmol Phenylalanine/min) in the active comparator group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb 3-methylhistidine rate of appearance (experimental group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb 3-methylhistidine rate of appearance (nmol 3-methylhistidine/min) in the experimental group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.
Within-group change in lower limb 3-methylhistidine rate of appearance (active comparator group)	Time = 165-180 minutes from start of study protocol to approximate Time = 315 minutes from start of study protocol.	The change in lower limb 3-methylhistidine rate of appearance (nmol 3-methylhistidine/min) in the active comparator group, from baseline to post-physiotherapy. Blood samples and lower limb blood flow measurements to determine protein kinetics are performed at baseline (before IV amino acids and physiotherapy) and at 30, 60, and 90 minutes during bed rest after the physiotherapy session.

Trial Locations

Locations (1)

Karolinska University Hospital; 🇸🇪 Huddinge, Stockholm, Sweden