Why ICU patients lose muscle so quickly

Have you ever wondered what happens to a person's muscles if they have to stay in the hospital for a long time, especially in the Intensive Care Unit (ICU)? A new study has shown that patients who are very sick and spend weeks in the ICU can lose a huge amount of muscle, which makes their recovery much harder. Let’s break down what scientists found, why it matters, and what it could mean for patients and their families.

What is ICU-acquired weakness?

When someone gets very sick and ends up in the ICU, their body is fighting hard to get better. But during this time, they often can't move around much, and their muscles do not get used as they normally would. This can lead to a problem called ICU-acquired weakness, or ICUAW, which is when muscles get much smaller and weaker the longer a person is in intensive care. This muscle loss can make it hard to walk, move, or even breathe on your own.

How much muscle do ICU patients really lose?

Researchers wanted to know just how much muscle ICU patients lose, especially those with serious illnesses like COVID-19 and severe pancreatitis (a painful swelling of the pancreas). In a study of 154 patients who spent at least 10 days in the ICU, scientists used CT scans to measure the size of a big muscle in the lower back called the psoas muscle. They found that on average, patients lost about 46% of this muscle during their time in the hospital. That means nearly half of their muscle just faded away! Even more surprising, patients with COVID-19 lost their muscle almost twice as fast as those with pancreatitis. The COVID-19 group lost about 1.88% of their muscle each day, compared to 0.98% in pancreatitis patients (full study here).

What makes muscle loss worse?

The researchers discovered that some factors made muscle loss even worse. The main ones were:

• The type of illness (COVID-19 led to faster muscle loss)

• How long a person stayed in the hospital

• Whether the person was overweight or obese

Obesity was especially tricky. Even though having more body mass might sound protective, in this study, obese patients lost muscle faster—possibly because their bodies had more inflammation and stress. This matches what other scientists have seen before (obesity and pancreatitis research).

Why does muscle loss matter?

Losing so much muscle is not just about being weaker. Muscle is important for moving, but it also helps you heal, keeps your immune system strong, and stores energy for your body. When ICU patients lose a lot of muscle, it can take them much longer to recover, and they might have trouble doing basic things like sitting up, walking, or even breathing without help. Studies show that less muscle can mean more time on machines that help you breathe, more infections, and a higher chance of complications (muscle loss and survival study).

How do doctors measure muscle loss?

Doctors and scientists are using new tools, including health AI, to measure muscle loss more accurately. In this study, they used artificial intelligence to look at CT scans and automatically measure muscle size. This makes it easier to track changes over time and helps doctors spot problems early. If you’re interested in how AI helps with medical images, you might like this article about how deep learning helps doctors read medical scans.

What can patients and families do?

If someone you love is in the ICU for a long time, it’s important to know that muscle loss is common—even expected. Doctors may try to get patients moving as soon as it is safe, and nutrition specialists work to provide enough protein and calories to help rebuild muscle (nutrition guidelines for pancreatitis). Asking about physical therapy, special diets, or new monitoring methods can be helpful.

It’s also a good idea to stay informed about how technology like health AI is being used in hospitals. And, as more health data gets collected, it is wise to learn about privacy issues. For tips on protecting your medical information when using AI tools, check out this guide on how to keep your health data private with AI.

The big picture

This research helps us understand that muscle loss in the ICU is serious and can happen very quickly, especially in patients with diseases like COVID-19. Knowing the risks can help families, doctors, and patients work together to fight muscle loss and improve recovery. As artificial intelligence and other technologies continue to develop, tracking and managing muscle health may become even easier and more personalized for every patient.