About this trial

Up to 60% of patients admitted to the Intensive Care Unit (ICU) with a prolonged stay in the ICU develop complications such as intensive care unit acquired weakness (ICUAW) characterized by limb and respiratory muscle weakness. ICUAW is associated with worse prognosis, longer ICU stay and increased morbidity and mortality.

Physical therapy (PT) interventions in the intensive care unit (ICU), can improve patients' outcomes.

However, improvements in muscle function achieved with standard physical activity interventions aiming at early mobilization are highly variable due to lack of consistency in definition of the interventions, lack of consideration for the complexity of exercise dose and/or insufficient stimulation of muscles during interventions. It has been suggested that modifying early mobilization and exercise protocols towards shorter intervals consisting of higher intensity exercises might result in more optimal stimulation of muscles.

In the present study the researchers therefore aim to simultaneously assess (by non-invasive technologies) locomotor muscle oxygenation and activation along with the measurements of the load imposed on respiration and circulation during two different training modalities i.e., moderate intensity continuous bed-cycling (endurance training) vs high-intensity alternated by lower intensity periods of bed-cycling (interval training).

Eligibility criteria

This trial does not accept healthy volunteers

Qualifiers

Full cooperatively adult patients indicated by the Adequacy Score of standardized 5 questions (SQ5) = 5/5

Patients mechanically ventilated for longer than 48 hours during the same ICU admission

Patients are expected to remain in the ICU for more than an additional 48 hours starting from study enrollment

Patients able to perform active cycling for > 10 consecutive minutes

Disqualifiers

Pre-existing functional limitations

Low limb injuries or conditions that would preclude in-bed cycling such as a body habitus unable to fit the bike

Extreme obesity (body mass index >35 kg/m2)

Neurologically unstable

Trial design

Design model

Crossover

Treatments tested in this trial

Constant-load bed-cycling exercise
Other intervention
Patients will actively cycle for a minimum duration of 10 minutes and a maximum duration of 20 minutes without breaks.
Interval bed-cycling exercise
Other intervention
Patients will cycle for the same duration as during constant-load exercise. Interval bed-cycling session will consist of 30 seconds of high intensity exercise alternated by 30 seconds of passive cycling designed so that volume of training will be equal.

Treatment groups

100 Participants

are divided into 2 treatment groups

Group A: Arm 1 (First constant-load then interval bed-cycling protocol)Active comparator 2 interventions

Group B: Arm 2 (First interval then constant-load bed-cycling protocol)Active comparator 2 interventions

Trial outcomes

Primary outcomes

1

Differences between bed-cycling protocols in fractional oxygen saturation (StiO2,%) for each measured region of the m. quadriceps femoris

Assessed by near-infrared spectroscopy

Time frame

constant-load and interval bed-cycling protocols administered in 2 different days within 1 week

2

Differences between bed-cycling protocols in activation (sEMG amplitude) for each measured region of the muscle quadriceps femoris

Assessed by surface electromyography

Time frame

constant-load and interval bed-cycling protocols administered in 2 different days within 1 week

3

Adverse event rate during constant-load bed-cycling

Constant-load bed-cycling protocol will be considered as a safe intervention in case the adverse event rate will be less than 2.6%; adverse events: catheter/tube removal, increase in vasoactive medications \>5mcg/min, increase in systolic blood pressure \> 200 mmHg for \> 2min, decrease in mean arterial pressure \< 60 mmHg for \> 2 min, decrease in heart rate \< 50 bpm for \> 2 min, increase in heart rate \> 140 beats per minute for \> 2 min, increase in respiratory rate and sustained \> 5 min after session, decrease in peripheral capillary oxygen saturation \< 88% for \> 1 min requiring an increase in fraction of inspired oxygen \> 0.1 sustained \> 5 min)

Time frame

1 session of maximal 20 minutes of constant-load bed-cycling per patient

4

Adverse event rate during interval bed-cycling

Interval bed-cycling protocol will be considered as a safe intervention in case the adverse event rate will be less than 2.6%; adverse events: catheter/tube removal, increase in vasoactive medications \>5mcg/min, increase in systolic blood pressure \> 200 mmHg for \> 2min, decrease in mean arterial pressure \< 60 mmHg for \> 2 min, decrease in heart rate \< 50 bpm for \> 2 min, increase in heart rate \> 140 beats per minute for \> 2 min, increase in respiratory rate and sustained \> 5 min after session, decrease in peripheral capillary oxygen saturation \< 88% for \> 1 min requiring an increase in fraction of inspired oxygen \> 0.1 sustained \> 5 min)

Time frame

1 session of maximal 20 minutes of interval bed-cycling per patient

Secondary outcomes

1

Differences in Relative dispersion (RD) of fractional oxygen saturation (StiO2,%) among the different regions of quadriceps femoris as indicator of heterogeneity of fractional oxygen extraction among different regions of quadriceps femoris muscle.

Differences between exercise protocols in Relative dispersion (RD) of fractional oxygen saturation (StiO2,%) among the different regions of quadriceps femoris (i.e., vastus lateralis, vastus medialis, rectus femoris upper part and rectus femoris lower part) as indicator of heterogeneity of fractional oxygen extraction among different regions of quadriceps femoris muscle.

Time frame

1 session constant-load bed-cycling + 1 interval bed-cycling session administered in 2 different days within 1 week.

2

Differences between exercise protocols in oxygenated hemoglobin/myoglobin (OxyHb/Mb), deoxygenated hemoglobin/myoglobin (DeoxyHb/Mb) and total hemoglobin/myoglobin concentration (TotHb/Mb) for each measured region of quadriceps femoris

Differences between exercise protocols in oxygenated hemoglobin/myoglobin (OxyHb/Mb), deoxygenated hemoglobin/myoglobin (DeoxyHb/Mb) and total hemoglobin/myoglobin concentration (TotHb/Mb) for each measured region of quadriceps femoris (i.e., vastus lateralis, vastus medialis, rectus femoris upper part and rectus femoris lower part)

Time frame

1 session constant-load bed-cycling + 1 interval bed-cycling session administered in 2 different days within 1 week.

3

Differences in Median frequency of sEMG of different regions of quadriceps femoris

Differences in Median frequency of sEMG of different regions of quadriceps femoris (i.e., vastus lateralis, vastus medialis, rectus femoris upper part and rectus femoris lower part) between exercise protocols

Time frame

1 session constant-load bed-cycling + 1 interval bed-cycling session administered in 2 different days within 1 week.

4

Differences in relative dispersion (RD) of sEMG values among the different regions of quadriceps femoris as indicator of heterogeneity of activation among different regions of quadriceps femoris muscle.

Differences between exercise protocols in relative dispersion (RD) of sEMG values among the different regions of quadriceps femoris as indicator of heterogeneity of activation among different regions of quadriceps femoris muscle.

Time frame

1 session constant-load bed-cycling + 1 interval bed-cycling session administered in 2 different days within 1 week.

Locomotor Muscle Oxygenation and Activation During Acute Interval Compared to Constant-load Bed-cycling Exercise

About this trial

Eligibility criteria

Qualifiers

Disqualifiers

Trial design

Treatments tested in this trial

Treatment groups

Trial outcomes

Primary outcomes

Secondary outcomes

Other outcomes

Sponsors and contacts