Table 1.

Studies including mobilization in ECMO patients—sample size, intervention characteristics, outcomes, main results and complications.

Study	Sample	Intervention	Frequency and Duration	Outcomes	Main results	Complications
Turner DA et al., 2011, (Case series report)	Patient 1: with respiratory failure (cystic fibrosis) on VV-ECMO as a bridge to lung transplantation Patient 2: with end-stage cystic fibrosis and respiratory failure on VV-ECMO as a bridge to lung transplantation. Patient 3: with cystic fibrosis and respiratory failure due to influenza B infection on VV-ECMO as a bridge to lung transplantation	In all patients: –Strengthening and reconditioning exercises in the supine position (ankle pumps, heel slides, upper extremity stretching, and range of motion exercises) –Exercises in the sitting position –On the edge of the bed to strengthen the torso, upper extremities, and lower extremities (leg lifts, ankle rolls, and arm lifts) –Exercises in the standing position and ambulation	Patient 1 → 1 week Patient 2 → 1 week Patient 3 → 8 days	Lung transplantation	Successful bilateral orthotopic lung transplantation and weaning from ECMO	No rehabilitation-related complications
Lowman GD et al., 2012 (Case report)	1 patient with severe acute respiratory failure due to a cystic fibrosis exacerbation on VV-ECMO as a bridge to lung transplantation	–Therapeutic out-of-bed exercises (sitting on the edge-of-bed, steps to transfer to/from a chair) –Manual therapy –Integumentary protection techniques –Airway clearance techniques	9 days	Survival to lung transplantation	Successful bilateral orthotopic lung transplantation	No rehabilitation-related complications
Rahimi RA et al., 2013 (Case report study)	Patient 1: respiratory failure (worsening dyspnea and persistent right pneumothorax) on VV-ECMO as a bridge to lung transplantation Patient 2: respiratory failure (multidrug-resistant pneumonia) on VV-ECMO as a bridge to lung transplantation	–Supine therapeutic exercises –Active in-bed cycling –Sitting at the edge of the bed with assistance –30 min of active, in-bed cycling	12 days 3 days	Lung transplantation Lung transplantation	Successful right orthotopic lung transplantation Successful bilateral orthotopic lung transplantation	No rehabilitation-related complications No rehabilitation-related complications
Rehder KJ et al., 2013 (Retrospective case series)	4 out of 9 patients with end-stage lung disease on VV-ECMO as a bridge to lung transplantation	Stretching and resisted exercises, sitting, standing, and ambulation (mean distance of 780 m)	5 days	Unknown	↓ in the mechanical ventilation time after transplantation ↓ in total length of hospital and ICU after transplantation 1-year survival 100%	No rehabilitation-related complications
Abrams D et al., 2014 (Retrospective cohort study)	35 out of 100 consecutive patients on ECMO underwent active physical therapy → -19 of them as bridge to transplantation (16 on VV-ECMO and 3 on VA-ECMO) -16 of them as bridge to recovery (15 on VV-ECMO and 1 on VA-ECMO)	–Bed-level active-assisted range of motion –Sitting in bed –Sitting at the edge of the bed –Standing –Ambulation	7.2 ± 6.5 sessions in total per patient 2.8 sessions per patient per week	Survival to transplantation or discharge Discharge disposition among survivors Critical safety events	Of the 16 bridge to recovery patients → 14 (88%) survived to discharge. 10 out of 19 bridge to transplantation patients (53%) survived to transplantation → 9 (90%) of these 10 patients survived to discharge Improvement in functional capacity Other: no overall difference in mean ECMO blood flow rates or sweep gas flow rates	No rehabilitation-related complications
Cork G et al., 2014 (Case report)	1 patient with severe respiratory failure due to Influenza A (H1N1) on VV-ECMO	Chest physiotherapy (positioning, ventilator hyperinflation, expiratory chest wall shaking and suctioning)	2 to 3 times daily for 13 days	Unknown	Successful weaning from ECMO support Improved secretion clearance and pulmonary recovery	Unknown
Morris K et al., 2014 (Case report)	A 46-year-old woman with acute viral interstitial pneumonia on VV-ECMO	-Passive mobilization -Bedside sitting -Active exercises	Unknown	Unknown	Desaturation during the intervention managed by increasing the blood flow in ECMO No other complications related to cannulation and normal cardiac response to exercise (increase in heart rate and systolic blood pressure)
Pruijsten R et al., 2014 (Case report series study).	6 patients with respiratory failure on VV-ECMO	Exercises ranging room exercising in bed to walking outside the room	4–17 days	Unknown	No cannulas’ dislocation 4 patients successfully bridged to bilateral lung transplantation Other: 4 patients were able to stand and walk a short distance up to 100 m 2 patients could sit upright with both legs hanging outside of the bed	No rehabilitation-related complications
Hermens JAJM et al., 2015 (Retrospective analysis)	9 awake, non-intubated patients with end-stage lung disease on VV-ECMO as a bridge to lung transplantation	-Extensive sputum mobilization -Muscle training of the lower extremities (dynamic quadriceps training by leg press, bed bike or squats from sitting position) -Bed-to-chair mobilization	Unknown	Muscle strength (Medical Research Council -MRC)	↑ in lower body muscle strength [mean MRC from 3.75 (range 3–4) before training to 4.25 (range 4–5) 1 day before transplantation] Other: 4 patients successfully bridged to lung transplantation 5 patients did not survive to transplantation	-1 patient with large rectus hematoma -1 patient with obstructing thrombus in the return cannula
Kikukawa T et al., 2015 (Case report)	A 54-year-old man with H1N1 influenza-associated respiratory failure and severe obesity on VV-ECMO	Respiratory therapy and bedside sitting	3 days	Unknown	Improvement in respiratory function Successful decannulation on ICU 3 days after physical therapy Discharge from the ICU 5 days after physical therapy Discharged from the hospital with no severe disability	No rehabilitation-related complications
Ko Y et al., 2015 (Retrospective study)	8 patients on ECMO: -7 patients on VV-ECMO → 2 of them as a bridge to recovery and 5 as a bridge to lung transplantation -1 patient on VA-ECMO as a bridge to heart transplantation	-31 sessions (50%) of passive range of motion and electrical muscle stimulation -17 sessions (27.4%) sitting in bed or on the edge of bed -2 sessions (3.2%) strengthening in sitting -11 sessions (18%) standing or marching in place -1 session (2%) walking	62 sessions	Safety events during physical therapy and interruptions due to unstable vital signs	Three sessions (5%) were stopped due to tachycardia (n = 1) and tachypnea (n = 2) during standing or marching in place Improvement in functionality and fitness
Kulkarni T et al., 2015 (Case report)	A 36-year-old man with status asthmaticus on VV-ECMO	Active rehabilitation and ambulation (800 feet/day)	2 days	Unknown	Successful weaning from ECMO 2 days after rehabilitation Hospital discharge 5 days after rehabilitation	No rehabilitation-related complications
Pastva A et al., 2015 (Case report)	A 30-year-old woman with cystic fibrosis and respiratory failure due to severe pneumonia on VV-ECMO as a bridge to lung transplantation	-Functional electrical stimulation cycling in quadriceps, hamstrings, and buttocks bilaterally -Progressive mobilization	7 functional electrical stimulation sessions (2 pre and 5 post transplantation) for over 18 days	Efficacy of functional electrical stimulation before and after bilateral orthotopic lung transplantation	Maintenance of the muscle mass of the rectus femoris (1.5–1.6 cm) and vastus intermedius (0.95–1.15 cm) during hospitalization Increase in muscle mass after hospital discharge of more than 2 cm in both muscles Improvement in muscle strength at ICU discharge (MRC sum score of 58/60 and hand grip strength of 60 pounds)	No rehabilitation-related complications
Bain JC et al., 2016 (Retrospective cohort analysis)	5 out of 9 patients with respiratory failure on VV-ECMO as a bridge to lung transplantation	Active physical rehabilitation and ambulation	Unknown	Economic impact of ambulatory versus non-ambulatory ECMO strategies	↓ by 22% in total hospital cost, by 73% in post-transplant ICU cost and by 11% in total cost in ambulatory ECMO patients compared with non-ambulatory ECMO subject Other: Lower length of mechanical ventilation before transplantation and higher ECMO support in ambulatory ECMO patients Shorter length of mechanical ventilation and ICU stay after transplantation in ambulatory ECMO patients	Unknown
Boling B et al., 2016 (Retrospective case series study)	18 patients with severe respiratory failure on VV-ECMO	-Physical therapy -Range of motion at the bedside -Ambulation in the hospital	Unknown	Unknown	8 patients (44%) received a transplant and survived to discharge Rest of the patients (10): 4 out o were successfully weaned from VV-ECMO 6 died	No rehabilitation-related complications
Keibun R. 2016 (Prospective observational study)	10 awake and 13 non-awake patients with refractory acute respiratory failure on VV-ECMO as a bridge to recovery (23 patients out of 31 who survived to ICU discharge)	Active rehabilitation	Unknown	Unknown	-Shorter length of stay in the ICU (13.6 vs. 21.7 days) in awake compared to non-awake ECMO patients -Shorter hospital stay (41.9 vs. 60.0 days) in awake compared to non-awake ECMO patients -Better improvement in the self-ambulation rate at discharge (70% vs. 38.5%) in awake compared to non-awake ECMO patients -Reduction in the total cost ($673,000 vs. $814,000) in awake compared to non-awake ECMO patients	Unknown
Norrenberg M et al., 2016 (Case series study)	10 patients with respiratory or cardiac failure on ECMO (5 on VV-ECMO and 5 on VA-ECMO)	Mobilization of all joints except for the limb used for ECMO cannulation	Unknown	Unknown	4 deaths (40%)	No rehabilitation-related complications
Munshi L et al., 2017 (Retrospective cohort study)	61 ARDS patients on ECMO out of 107 as a bridge to recovery (57 on VV-ECMO and 4 on VA-ECMO) → 50 patients of them underwent physiotherapy while 11 did not (47 on VV-ECMO and 3 on VA-ECMO)	-Passive ROM -Active ROM -Sitting -Standing -According to ICU Mobility Scale	Unknown	Association between ICU physiotherapy and ICU mortality Factors associated with a higher intensity activity score	Association with ICU mortality (p < 0.05): ICU physiotherapy (OR 0.19; 95% CI 0.04–0.98) APACHE II (OR 1.13; 95% CI 1.01–1.26) Sex (OR 8.4; 95% CI (1.71–41.7) No clinical characteristics were independently associated with the intensity of ICU physiotherapy except for SAS	No rehabilitation-related complications Only complications related to ECMO (such as barotrauma, limb ischemia, intracerebral hemorrhage, HIT, air embolism)
Salam S et al., 2017 (Case report)	A 50-year-old man with severe ARDS on VV-ECMO as a bridge to lung transplantation	-Active exercises with elastic bands -Mini-leg press -Bedside sitting -Ambulation	125 days	Lung transplantation	Improvement in fitness before lung transplantation Successful bilateral lung transplantation after 125 days on ECMO	Cannula fracture during ambulation
Shudo Y et al., 2018 (Case report)	1 patient on VA-ECMO while awaiting en-bloc heart-lung transplantation	-45-degree tilt and 40% weight-bearing for 30 min in the first day -Full tilt and weight bearing for 30 min after 7 days -Step off and ambulate several feet at bedside with assistance after 10 days -Ambulation for 30 min with minimal assistance and strengthening exercises after 14 days	19 days	Unknown	Successful en-bloc heart-lung transplantation after 19 days Hospital discharge 12 days after transplantation	No rehabilitation-related complications
Wells CL et al., 2018 (Retrospective cohort study)	167 out of 254 patients on ECMO (98 on VV-ECMO and 69 on VA-ECMO)	-Therapeutic exercises (range of motion, stretching and strengthening exercises, muscle endurance, breathing exercises) -Bed mobility (rolling, supine to sit transfer training, bridging activities) -Edge of bed activities (sitting balance, posture, pre-standing activities, breathing and coughing) -Sit to stand transfer activities (sit to standing transfers and functional strengthening using sit to stand from the bed or chair) -Stand pivot transfers (pivot or taking small steps from the bed or chair with purpose to transfer to another surface) -Standing activities (standing balance and tolerance, strengthening, weight shifting, marching, and stepping in place) -Ambulation (gait training, gait speed, ambulation tolerance)	268 interventions 170 interventions 100 interventions 106 interventions 39 interventions 98 interventions 37 interventions	-Discharge disposition -Adverse events	109 survivors out of 167 patients (65%) VA ECMO: 41 out of 69 (59%) patients with hospital discharge VV ECMO: 68 out of 98 (69%) patients with hospital discharge	3 minor events (< 0.5%) → 2 episodes of arrhythmias (non-sustained ventricular tachycardia) and 1 hypotension event
Pasrija C et al., 2019 (Retrospective study)	15 out of 104 patients with decompensated heart failure and pulmonary embolism on VA-ECMO	-Motor strength exercises (moving to the chair or walking)	Unknown	Safety and feasibility of ambulation (absence of major bleeding, vascular, or decannulation events)	-3 minor bleeding events (20%) -100% in-hospital survival
Braune S et al., 2020 (Prospective observational study)	43 out of 115 critically ill patients on ECLS with IMS ≥ 3 (12 on VV-ECMO, 17 on VA-ECMO, 7 on VV-ECCO2R, 3 on AV-ECCO2R and 4 on RVAD)	-Functional strengthening -Breathing exercises -Active upper and lower limb exercises -Endurance exercises -Progressing functional mobility	332 mobilizations (100 on VV-ECMO, 72 on VA-ECMO, 48 on VV-ECCO2R, 63 on AV-ECCO2R and 49 on RVAD) 130 min (IQR 44–215) median duration of all mobilization activities	Complications during mobilization	-3 out of 43 (6.9%) patients with bleeding from cannulation site requiring transfusion and/or surgery -1 episode (0.3%) of femoral cannula displacement during mobilization on VA-ECMO patient
Mark A et al., 2020 (Case report)	1 pregnant woman with acute respiratory failure due to COVID-19 on VV-ECMO	-In-bed active-assisted range-of motion exercises such as sitting at the bedside and standing -Out-of-bed activities including standing at the bedside, strength of standing force, pregait exercises	6 days	Unknown	Successful hospital discharge	1 episode of hypotension (mild dyspnea with activity and lightheadedness)
McCormack PF et al., 2020 (Randomised crossover trial)	3 patients on VV-ECMO	30-min active NMES session delivered to the quadriceps (biphasic, symmetric impulses of 45 Hz, with 400 μs pulse duration, 12 s on and 6 s off) and 30-min sham session (intensity at the minimum value of 1–5 mA, without palpable contractions)	30 min/session	Pedal perfusion assessed via a combination of laser speckle contrast imaging (LSCI), non-imaging laser doppler (NILD) flowmetry, and transcutaneous oximetry (PtcO2)	Minimal change in pedal perfusion during NMES in 2 patients ↑ in pedal perfusion during NMES on the LSCI data in 1 patient	No rehabilitation-related complications
Mao L et al., 2021 (Case report)	1 patient with severe COVID-19 after bilateral lung transplantation on VV-ECMO	-Ventilation in the prone position → 12 h each day for 3 consecutive days -Ventilation in the supine position → 30 min each time, 4 times a day -Breathing training → 10 min each time, 2 times a day -Airway clearance technique → active breathing techniques once every hour -Exercise training → thoracic expansion exercises -Endurance training → bedside cycle ergometer for 20–30 min a day with moderate to slightly high intensity -Strength training → 6 to 10 RM weight training of the upper and lower limbs for 10–30 min, once or twice a day initially and 3 to 4 times a day later -Transfer training from the bed to the bedside, from the bedside to a chair, and from the chair to the bed repeatedly for 30 min each time, 2 times a day -Daily therapeutic bronchoscopy	2 days on ECMO (then ECMO was removed and the patient continued rehabilitation without ECMO)	Discharge from ECMO	Successfully removal of ECMO one day after rehabilitation	No rehabilitation-related complications

ICU, intensive care unit; IMS, intensive care unit mobility scale; ECMO, extracorporeal membrane oxygenation; VA, veno-arterial; VV, veno-venous; ECLS, extracorporeal life support; VV-ECCO₂R, veno-venous extracorporeal carbon dioxide removal; AV-ECCO₂R, arterio-venous extracorporeal carbon dioxide removal; RVAD, right ventricular assist device; NMES, neuromuscular electrical stimulation; HIT, heparin induced thrombocytopenia; SAS, sedation agitation scale; ROM, range of motion; RM, repetition maximum.