Rehabilitation decides severely ill patients’ quality of life, even reducing mortality

When people think of an intensive care unit, they imagine an “unconscious patient” lying there with multiple tubes and lines. It's a place where patients are in critical condition, and the focus is on getting them out alive.

At first glance, the only thing we worry about when we see patients lying in bed for a long time is little more than bedsores. However, many patients experience unexpected side effects after leaving the ICU. This is due to functional decline caused by prolonged immobilization.

Physical disability is a common problem caused by decreased function. Even young patients in their 20s and 30s can lose muscle mass after a week in the ICU and not be able to walk right away. This is called ICU-acquired weakness (ICUAW). It has been reported that 67 percent of patients on a ventilator for 10 days or more develop ICUAW (Critical Care, 2015).

50-70% of ICU survivors experience PICS

ICU-acquired weakness can be difficult to treat, and patients often struggle to regain physical function long after discharge.

The New England Journal of Medicine (NEJM) reported 2011 that 61 percent of patients who received intensive care unit treatment for acute respiratory failure had less than 80 percent of their expected walking ability five years after discharge.

“It's not just disused weakness, where muscles become weak while lying in bed, but also severe neuromuscular disease, which is a type of multiorgan failure,” said Professor Kim Won of the Department of Rehabilitation Medicine at Asan Medical Center. “ICU-acquired weakness not only causes a decline in motor skills, including gait but also delays ventilator weaning and adversely affects ICU length of stay and survival.”

Professor Kim said that after ICU treatment, patients may experience muscle atrophy, bone loss, joint contractures, swallowing difficulties, decreased ability to perform activities of daily living, fatigue, and insomnia.

Cognitive impairment, such as delirium, poor language skills, and memory and concentration, can also occur. According to the Journal of the American Medical Association (JAMA), a long-term cohort study of 1,194 patients hospitalized for severe sepsis in the United States found a 3.3-fold increased risk of moderate-to-severe cognitive dysfunction.

Some patients also complain of psychiatric disorders, including depression and anxiety. “Even one year after ICU discharge, about one-third of survivors reported clinically significant depressive symptoms,” Kim said.

The physical, cognitive, and mental impairments that result from this decline in function are known as Post-Intensive Care Syndrome (PICS). Not all ICU patients develop PICS, but the incidence is high.

A 2016 study in the Journal of the American Academy of Physician Associates (JAAPA) reported that 50-70 percent of ICU survivors experience PICS. A 2021 study published in Critical Care by Japanese researchers also found that 63.5 percent of critically ill patients experienced at least one disability six months after discharge from the ICU. In the Netherlands, 58 percent of internal medicine critically ill patients and 64 percent of critically ill surgical patients who underwent emergency surgery experienced PICS (Am J Respir Crit Care Med, 2021).

Patients over the age of 65 and those with underlying medical conditions are particularly at risk for PICS. The intensity of ICU care and severity of organ failure also increase the risk of PICS.

“Prolonged mechanical ventilation treatment increases the risk of ICU-acquired weakness by causing muscle wasting and bed rest,” said Professor Yeo Hye-ju of the Department of Respiratory Medicine at Pusan National University Yangsan Hospital, who found that ICU-acquired weakness occurs in 25 to 50 percent of survivors. In addition, 50 percent of survivors experience long-term breathing problems, and 10-30 percent report post-traumatic stress disorder (PTSD).

Even if patients survive the ICU, PICS can often rock their lives afterward. When Japanese researchers followed up with 328 survivors of ICU care, 24 percent were still unemployed a year after discharge (PLOS ONE, 2022).

Effectiveness of rehabilitation for severely ill patients has been proven overseas

There is prevention – critical care rehabilitation. Early rehabilitation for patients admitted to the ICU can reduce their length of stay and help them get back to their normal routine faster. The effectiveness of rehabilitation for critically ill patients has been proven abroad. Developed countries have established related systems, including payment systems, to include rehabilitation in the critical care process.

“The condition of the ICU patient determines the stage of treatment and patients who can cooperate need active rehabilitation where they can actively participate in using their muscle strength,” Professor Kim said. “Rehabilitation is possible for patients who are intubated or on a ventilator, as well as those on ECMO (extracorporeal membrane oxygenation).”

If basic safety standards are followed, adverse events that affect patient health are rare. However, Kim emphasized that collaboration among multidisciplinary team members is essential for safe and effective rehabilitation.

“If there is a problem that affects the patient's health status and recovery, it is recommended to diagnose and treat it with PICS,” Professor Kim said. “The Post-Intensive Care Syndrome Questionnaire (PICSQ), Healthy Aging Brain Care Monitor (HABC-M), Mini-Mental State Examination (MMSE), and Montreal Cognitive Assessment (MoCA) can be used as assessment tools.”

Professor Lee Hak-jae of the Department of Acute Care Surgery at Asan Medical Center said that studies consistently show that rehabilitation therapy for critically ill patients effectively prevents PICS.

In 2009, the international journal Lancet published a study that showed that rehabilitation of critically ill patients reduced the duration of delirium by about two days and mechanical ventilation by 2.7 days. In 2022, a study reported in Critical Care Medicine showed that rehabilitation reduced ICU length of stay by 1.2 days. In 2024, Critical Care Medicine published a study showing that early rehabilitation reduced mechanical ventilation by an average of 1.76 days and ICU length of stay by 1.16 days. The frequency of ICU-acquired weakness was lower in critically ill patients who received rehabilitation, and the prevalence of cognitive impairment was also reduced after one year (Lancet Respir Med, 2023).

“Early rehabilitation prevents functional decline due to muscle weakness and bed rest and promotes patients' independent mobility and activities of daily living,” Professor Yeo said. “In recent studies, early rehabilitation has been shown to reduce in-hospital mortality and decrease mean length of stay and readmission rates in patients with heart failure.”

Early rehabilitation has been proven effective in restoring short-term physical function and shortening hospitalization, and studies are ongoing to determine long-term functional outcomes and quality of life, Yeo added.