When people are very sick and stay in the intensive care unit (ICU), their stomachs and digestive systems often stop working normally. Researchers studied 100 critically ill patients to understand how common these stomach problems are, what causes them, and whether they affect how long patients stay in the hospital. They found that every single patient had at least one stomach problem, and nearly half had severe issues. Patients with severe stomach dysfunction stayed in the ICU longer and needed breathing machines for more days. The study suggests that doctors should regularly check for and monitor stomach problems in ICU patients because catching these issues early might help improve care.

The Quick Take

  • What they studied: How often stomach and digestive problems happen in ICU patients, how serious they are, what causes them, and whether they affect patient recovery
  • Who participated: 100 very sick adults in the hospital’s intensive care unit (average age 53 years old, 61% men). Most were in general ICU, some in cardiac ICU. All patients needed feeding tubes or IV nutrition and were expected to stay at least 3 days
  • Key finding: Every patient studied had at least one stomach problem, and nearly half had severe issues. Patients with severe stomach problems stayed in the ICU about 3 days longer and needed breathing machines for about 1.5 extra days
  • What it means for you: If you or a loved one is in the ICU, doctors should regularly check for stomach problems because these issues are very common and may affect recovery time. Early detection might help doctors make better treatment decisions

The Research Details

Researchers watched 100 ICU patients over about 18 months (from February 2019 to July 2020) and carefully recorded everything about their stomach and digestive health from the moment they arrived until they left the hospital or after 90 days. They used two different scoring systems to measure stomach problems—one called AGI and another called GIDS—to make sure they were catching all the issues.

They tracked specific stomach symptoms like inability to tolerate food, vomiting, constipation, and diarrhea. They also noted what treatments doctors used, how sick the patients were overall, and what happened to them (how long they stayed, whether they needed breathing machines, and whether they survived).

The researchers used statistical methods to figure out which factors made stomach problems more likely to happen and whether stomach problems were connected to longer hospital stays or other bad outcomes.

This study design is important because it watches patients in real time rather than looking back at old medical records. This means the researchers could catch stomach problems as they happened and see exactly how they developed. By using two different scoring systems, they made sure they weren’t missing any stomach problems and could measure severity accurately.

The study has some strengths: it carefully tracked patients from admission to discharge, used standardized scoring systems, and adjusted for other factors that might affect results. However, the study is relatively small (100 patients) and used a convenience sample rather than randomly selecting patients, which means the results might not represent all ICU patients perfectly. The study was done at specific hospitals, so results might differ in other locations.

What the Results Show

The most striking finding was that every single patient in the study had at least one stomach or digestive problem. Using one scoring system (AGI), all 100 patients showed signs of gut dysfunction. Using another system (GIDS), 79 out of 100 patients had problems. When looking at severe problems, 46% of patients had severe dysfunction by AGI standards, and 25% had severe dysfunction by GIDS standards.

Patients whose original reason for being in the ICU was related to stomach or digestive issues were much more likely to have severe problems. These patients had about 10 times higher odds of severe dysfunction compared to patients admitted for other reasons.

Blood tests showing high lactate levels (a sign the body isn’t getting enough oxygen) were connected to worse stomach problems. Patients with severe stomach dysfunction stayed in the ICU about 3 days longer (13 days versus 10 days) and needed breathing machines for about 1.5 extra days (12 days versus 10.5 days).

Interestingly, the amount of fluid doctors gave patients was connected to stomach problems—for every extra liter of fluid, stomach dysfunction scores got worse. Pushing patients to eat more aggressively through feeding tubes increased the odds of severe dysfunction by 82%.

Patients receiving multiple heart-support medications (inotropes) had worse stomach dysfunction scores at the 72-hour mark. The overall death rate in the ICU was 21%, but stomach dysfunction severity didn’t appear to directly affect survival rates in this study, which was somewhat surprising.

This study confirms what many doctors have suspected: stomach problems are extremely common in ICU patients. Previous research suggested stomach dysfunction might be important, but this study provides clearer evidence about how common it is and which patients are at highest risk. The finding that aggressive feeding might make stomach problems worse aligns with recent thinking that gentler feeding approaches might be better for very sick patients.

The study only included 100 patients, which is relatively small, so results might not apply to all ICU patients everywhere. The researchers used a convenience sample (selecting available patients) rather than randomly assigning patients, which could introduce bias. The study was done at specific hospitals in a particular time period, so results might differ in other settings. The study didn’t show that stomach dysfunction directly caused death, which makes it harder to know how much it truly affects survival. The researchers couldn’t control for all possible factors that might affect stomach health.

The Bottom Line

Healthcare providers should regularly assess stomach function in all ICU patients using standardized scoring systems (moderate confidence). Doctors should be cautious about aggressive feeding through tubes in very sick patients and may want to use gentler feeding approaches (moderate confidence). Monitoring fluid balance carefully is important since excess fluid appears connected to worse stomach problems (moderate confidence). Patients with stomach-related reasons for ICU admission need especially close monitoring for severe dysfunction (high confidence).

This research matters most for ICU doctors and nurses who care for critically ill patients. It’s relevant for patients and families with loved ones in the ICU, as it explains why doctors might be cautious about feeding and fluids. It’s less directly relevant for people who aren’t in critical care situations, though it may inform general understanding of how the body responds to severe illness.

Stomach problems in ICU patients develop quickly—the study found that fluid balance and feeding approaches affected stomach function within the first 72 hours. Improvements in stomach function might be seen within days if doctors adjust feeding and fluid management, but this varies greatly depending on the underlying illness.

Want to Apply This Research?

  • If a loved one is in the ICU, track daily stomach symptoms (tolerance of feeding, vomiting, constipation, diarrhea) and note any changes in feeding approach or fluid amounts. Record the date, symptom type, and severity to share with the medical team.
  • For ICU patients or their caregivers: Ask the medical team daily about stomach function assessment and whether the current feeding plan is working. Request gentle feeding approaches rather than aggressive feeding if the patient is having trouble tolerating nutrition.
  • Keep a simple daily log of stomach symptoms and feeding tolerance throughout the ICU stay. Note any changes in medications (especially heart-support drugs) or fluid amounts, as these appear connected to stomach problems. Share observations with nurses and doctors to help guide treatment decisions.

This research describes patterns observed in ICU patients but should not be used for self-diagnosis or to replace medical advice from healthcare providers. If you or a loved one is in the ICU, all treatment decisions should be made in consultation with the medical team caring for them. This study involved a relatively small number of patients at specific hospitals, so results may not apply to all situations. Always follow your doctor’s recommendations regarding feeding, fluids, and other treatments.