A Major ICU Trial Finds That Getting Ventilated Patients Moving Earlier Does Not Guarantee Better Recovery
For years, intensive-care clinicians have treated early mobilization as one of the most promising ways to protect patients from the physical damage of critical illness. The logic is compelling: people who spend days connected to a mechanical ventilator can rapidly lose muscle mass and strength, while prolonged bed rest may impair balance, walking ability and independence long after the original infection or respiratory crisis has passed. But a large multicenter trial in South Korea has now delivered a more complicated message. A structured six-step mobilization program helped patients begin moving sooner and increased the amount of rehabilitation they received, yet it did not improve their functional status when they left the intensive-care unit—and it did not produce better physical, cognitive or psychological outcomes over the following year.
The EVER trial, published in Intensive Care Medicine, enrolled 169 adults being treated for sepsis or acute respiratory failure who were expected to require invasive mechanical ventilation for at least 48 hours. The participants were randomly assigned to either a protocolized early-mobilization program or usual care at five tertiary hospitals in South Korea between September 2020 and July 2024. Randomization is designed to distribute known and unknown differences between groups, allowing researchers to estimate whether an intervention itself caused a difference in outcomes. In this open-label study, clinicians knew which treatment each patient received, but the main analysis followed the intention-to-treat principle, meaning participants were evaluated according to their assigned group rather than according to how closely they followed the protocol.
Mechanical ventilation can be lifesaving, but critical illness and immobility impose a biological toll. Sepsis triggers a widespread inflammatory response that can disrupt muscle metabolism, damage nerves and alter the body’s ability to generate energy. Sedative medications, deep sedation, systemic inflammation, poor nutrition and prolonged inactivity may combine to produce intensive-care-unit-acquired weakness. At the cellular level, muscles can lose contractile proteins and undergo changes in mitochondrial function; at the whole-body level, patients may struggle to sit, stand or walk even after the ventilator is removed. Cognitive impairment, anxiety, depression and post-traumatic stress symptoms can also emerge, a cluster of problems often called post-intensive-care syndrome, or PICS. Early rehabilitation is intended to interrupt some of these processes by providing controlled physical activity while patients are still critically ill.
The EVER intervention used a progressive, six-step approach that advanced according to a patient’s clinical condition and physical capability. Although the study’s abstract does not list every exercise in the sequence, the reported progression included increasingly active tasks, culminating in sitting to stand or more demanding activity. Such protocols generally begin with passive movement of the limbs for patients unable to participate, then progress to active-assisted exercises, repositioning, sitting in bed, sitting at the edge of the bed, standing and eventually walking. Each step requires clinicians to balance the potential benefits of loading muscles and restoring motor control against risks such as oxygen desaturation, unstable blood pressure, arrhythmias, accidental removal of tubes or excessive fatigue. The intervention therefore was not simply a recommendation to “exercise”; it was a coordinated program delivered within the safety constraints of an ICU.
The program clearly changed what happened at the bedside. Patients assigned to structured mobilization began their first session after a median of 30.0 hours, compared with 45.9 hours in the usual-care group. They also received a median of 11 mobilization sessions, versus four under usual care, and accumulated 330 minutes of mobilization time, compared with 120 minutes. Those differences show that a protocol can overcome at least some of the inertia that keeps critically ill patients in bed. Yet the trial’s primary endpoint, the Functional Status Score for the ICU, or FSS-ICU, was not significantly different at discharge. The intervention group had a mean score of 23.6, with a standard deviation of 11.8, while the usual-care group averaged 22.2, with a standard deviation of 10.8. The probability value was 0.44, well above the conventional threshold used to identify statistical significance.
The result becomes more intriguing when the researchers examined how far patients actually progressed. Participants who reached mobilization Step 4 or higher—defined as sitting to stand or a more advanced activity—had substantially better functional scores at ICU discharge than matched patients receiving usual care. Their mean FSS-ICU score was 30.6, compared with 23.3 in the comparison group, a difference reported as statistically significant at P<0.01. This finding suggests that the amount and intensity of activity may matter more than simply starting early. However, it cannot establish that reaching the higher step caused the better result. Patients who are strong enough, alert enough and medically stable enough to stand may already be on a faster recovery trajectory. In statistical terms, achievement of advanced mobilization is partly a marker of underlying health, creating the possibility of confounding even when the original trial itself was randomized.
The investigators also tracked recovery at one, three, six and 12 months using a broad set of measures. These included EQ-5D, which assesses health-related quality of life across five dimensions; the physical and mental component summaries of the SF-36 questionnaire; the Korean version of the Impact of Event Scale–Revised, which screens for trauma-related symptoms; a vision-independent cognitive assessment known as MoCA-BLIND; and measures related to post-intensive-care syndrome. Across the year, outcomes improved in both groups, but no significant long-term differences emerged. That pattern is important because recovery after critical illness is dynamic. A small early advantage might disappear as patients receive rehabilitation after discharge, regain strength through ordinary activity or recover from the underlying disease. Conversely, the absence of a measurable group difference at 12 months does not mean the intervention was harmlessly irrelevant; it may have helped individual patients without shifting average outcomes across the entire study population.
The trial’s findings challenge the idea that “earlier and more” mobilization is automatically better for every mechanically ventilated patient. Earlier studies have reported benefits from physical and occupational therapy, and clinical guidelines commonly encourage reducing unnecessary immobility. But results across trials have been mixed, partly because early mobilization is not a single treatment. Its effects may depend on sedation practices, staffing, nutrition, the severity and cause of illness, the timing of rehabilitation, the dose of exercise and whether patients can progress from passive movement to active standing and walking. A short session of passive range-of-motion exercise is physiologically very different from repeated walking while ventilated. The 2022 TEAM trial, for example, examined early active mobilization in mechanically ventilated patients and raised questions about whether higher-intensity activity can produce unexpected harms in some critically ill populations. The new South Korean trial adds evidence from Asian ICUs, where patterns of care, available rehabilitation resources and patient populations may differ from those in North America, Europe and Australia.
The study also has limitations that temper any sweeping conclusion. It enrolled only 169 participants, with 93 assigned to the intervention and 76 to usual care, so it may have lacked the statistical power to detect modest differences or effects in specific subgroups. The open-label design is unavoidable for a physical therapy intervention but can influence clinician behavior and patient-reported outcomes. Usual care was not immobility: participants in that group still received some mobilization, and the study shows that they accumulated a median of 120 minutes across four sessions. That relatively active comparison may have reduced the contrast between groups. The trial also took place in five tertiary hospitals in one country, limiting how directly its findings apply to smaller hospitals, different healthcare systems or patients with other causes of respiratory failure. Finally, the study’s results do not imply that rehabilitation should be abandoned. They indicate instead that a standardized early program, as delivered in this trial, did not improve the selected average outcomes compared with existing care.
For clinicians, the most useful message may be that timing alone is an incomplete prescription. Mobilizing a patient 16 hours earlier does not necessarily translate into greater independence if the patient never advances to weight-bearing activity, if sedation prevents active participation or if severe sepsis overwhelms the potential benefits of exercise. Future trials may need to identify which patients are most likely to benefit, define physiologically meaningful doses, and distinguish the effects of passive movement, cycling, sitting, standing and walking. They may also need to integrate mobilization with lighter sedation, delirium prevention, adequate protein delivery and rehabilitation that continues after hospital discharge. The EVER study found that patients in both groups improved over 12 months, a reminder that critical-illness recovery is shaped by many interacting systems rather than one intervention. Early mobilization remains biologically plausible and clinically valuable for selected patients—but this randomized trial shows that making it earlier and more structured is not, by itself, a guaranteed route to faster or better recovery.
