Traditionally, critically ill patients on mechanical ventilation have been managed with limited physical activity, largely influenced by the need for physiological stability and concerns about potential complications. This conventional approach often involved sedating patients to ensure comfort and safety, as well as to reduce metabolic demand while mechanical support helped them breathe. The strategy of keeping patients immobilised was perceived as a way to mitigate the risks of unplanned extubations, falls or cardiovascular events during physical movement.
In contrast, mobilisation strategies in the ICU setting emerged as a practice intended to gradually introduce movement to patients to counteract the detrimental effects of prolonged immobilisation. Passive range-ofmotion exercises were often employed initially, followed by active movements and, where feasible, activities such as sitting at the edge of the bed or walking short distances. However, these strategies were implemented with great caution, given the high risk of complications among mechanically ventilated patients.
Emerging evidence suggests, however, that this conservative approach should be revisited. Despite previous ideas around early mobilisation (EM), more research is revealing that there is no increased mortality associated with EM, challenging previous assumptions that movement poses significant dangers to critically ill patients on ventilators. “When I started, it was so routine to have patients awake shortly after intubation and walking within hours after, unless there was a certain exception or contraindication not to be,” explains Kali Dayton, DNP, AGACNP, ICU consultant and CEO at Dayton ICU Consulting. Working initially as a nurse practitioner at Aaliyah Hospital in Salt Lake City, Utah, she explains that sedation was rare at her first hospital with patients awake and mobilised three times a day.
However, this is out of the norm for a typical ICU. “Nobody really warned me about what it was like outside that bubble… suddenly, I was in this dark ICU and everyone was in bed,” she continues. “That was the very first time after working in critical care for over two years that it ever occurred to me that patients would automatically be in a medical coma the second they’re on a ventilator, but I quickly realised that was normal to everybody else.”
After working as a travel nurse and in lots of other ICUs for two years, Dayton returned to her first ICU in Utah and began looking into the research where she realised that traditional strategies for ventilated patients were more harmful than EM strategies, despite its widespread practice and acceptance. “I started to learn about post-ICU syndrome and that’s when I saw things for what they were and that my first ICU did things right,” explains Dayton. “They kept patients awake and mobile, protected them from these brain injuries, the physical impairments and psychological trauma of sedation and delirium, and losing your muscle mass while in bed.”
Reducing disadvantages, increasing advantages
EM has shown significant advantages in reducing the adverse effects associated with prolonged immobilisation and hospitalisation. Prolonged immobility is linked to muscle atrophy, joint contractures and a higher risk of deep vein thrombosis, all of which contribute to a lengthy and challenging recovery process once patients are discharged from the ICU. EM directly addresses these issues by promoting muscle engagement, preserving joint function and improving overall physical conditioning, leading to faster functional recovery. One study by WL Titsworth in the Journal of Neurosurgery in 2012, for example, showed a 300% increase in early mobility and decreased hospital acquired infections by 60%.
Research from recent trials has also highlighted the psychological benefits of EM. Patients who engage in even minimal physical activity experience lower rates of delirium and cognitive decline compared to those who remain immobile throughout their ICU stay, with one study finding that EM reduced their hospital length of stay due to delirium by 3.1 days. Another study in 2023 found that mobilising patients withing 48 hours after intubation improved cognitive levels by 20% one year after discharge. The ability to engage in physical activities, no matter how modest, can reduce the sense of disorientation and anxiety often experienced by patients, thereby supporting better mental health outcomes.
There’s also evidence suggesting that EM can lead to shorter ICU stays. By improving patients’ physical resilience and facilitating their recovery, this approach may reduce the amount of time required for ventilatory support and, consequently, the length of stay in both the ICU and the hospital. “For each additional 10 minutes of early mobility in the ICU, there’s a 1.2 day decrease in length of stay in the hospital,” adds Dayton. “Another study showed that for each unit of out-of-bed-mobility, there was a 10% decrease in time on the ventilator across all ICUs, but in the medical ICU, specifically, it was a 22% decrease in time on the ventilator.” Ultimately, this could translate into a more efficient allocation of healthcare resources and a reduction in the burden on the healthcare system.
That’s not to say that there has been no effort to introduce EM strategies, for example, the Society of Critical Care Medicine (SCCM) created the ABCDEF bundle over a decade ago to reduce pain, delirium prevention and to increase mobilisation, for example. “It didn’t have a strong impact on the culture,” Dayton points out, “there wasn’t a lot of education done for the entire ICU community to say, ‘Hey, we are harming patients with this, this is what we’re working towards’.”
From this bundle, however, came a study published in Critical Care Med in 2019, which found that the ABCDEF bundle decreased seven-day mortality by 68%, delirium by 25–50%, decreased readmissions to the ICU by 46% and discharges to anywhere but home by 36%. “This study came out and it was really exciting, but then Covid hit,” says Dayton. “We lost a lot of our experienced clinicians that knew anything about the bundle… so the community is trying to revitalise the bundle and get us back on course, but it’s been a struggle.”
Negative side-effects and outcomes of EM
While the benefits of EM are compelling, it is crucial to consider the potential risks associated with implementing mobilisation strategies. Historically, EM was linked with an increased risk of complications such as accidental extubations, falls and cardiovascular instability, leading many clinicians to approach it with caution. “There’s a lot of fear surrounding it,” explains Dayton. “You have patients that are very sick, they’ve got lines and drains, they’re on life supportive devices like ECMO or the ventilator.”
However, recent studies have cast doubt on the severity of these risks. Evidence published in Lancet Respiratory Medicine suggests that EM does not significantly impact mortality rates, and the incidence of serious adverse events is much lower than previously believed at less than 3%. Minor complications, such as transient drops in blood pressure or an increased need for sedation due to discomfort, have been observed but are generally manageable within the clinical setting. “We do need to use common sense and good parameters, but still allow for critical thinking so that we can still mobilise patients that are critically ill,” Dayton explains, while stressing that these risks need to be weighed against the long-term harm of immobility, which can lead to severe deconditioning and prolonged recovery periods.
Despite the growing body of evidence supporting the safety and efficacy of EM, several challenges remain in translating this knowledge into widespread practice. One of the most significant barriers is the culture and mindset within ICUs. The traditional emphasis on physiological stability and minimising movement has led to a conservative approach that can be difficult to shift.
“Everyone is usually trained into this culture of automatic sedation for everyone,” says Dayton. Staff, including nurses and respiratory therapists, may need training and education to understand the benefits and safety of EM, as well as the techniques required to perform it safely. “You have to have to be able to treat patients differently, knowing how to communicate with them, how to work them through anxiety, how to manage pain, how to mobilise them – that’s a lot of training and skills that you don’t develop unless you have the opportunity to do it.”
Logistical challenges also play a role. EM requires adequate staffing and resources, such as specialised equipment like mobility aids, lifting devices and adjustable beds. In many ICUs, where patient-to-staff ratios are high, implementing active mobilisation can be resource-intensive and time-consuming, which may limit the frequency and intensity of interventions that can be provided. “You have to have the staff to do this,” explains Dayton. “But we also know that this drastically decreases the staff required… it decreases the burden of the workload on the staff and the hospital.”
Patient-specific factors can also complicate efforts to mobilise patients early. Conditions such as hemodynamic instability, multiple comorbidities or profound muscle weakness can present significant obstacles, making it challenging to safely initiate mobilisation. Furthermore, variability in patient responses requires a high level of individualisation in care, necessitating that ICU staff closely monitor each patient’s physiological response to mobilisation efforts and adjust interventions accordingly.
The practice of EM in ventilated ICU patients has evolved considerably, with emerging evidence suggesting that the risks are far less than commonly believed. EM offers considerable benefits, including improved functional outcomes, reduced delirium and potentially shorter ICU stays. While challenges remain, particularly in shifting traditional ICU practices and addressing logistical constraints, the potential for improving patient outcomes makes the case for revisiting and integrating EM into standard care protocols.
With the growing evidence base, EM is poised to become a key component of ICU care, providing a pathway to improved quality of life and faster recovery for ventilated patients. Moving forward, enhancing education, adjusting clinical guidelines and ensuring adequate staffing and resources will be essential steps in making EM an integral part of ICU practice.
