Postoperative complications often develop unnoticed. Children may not understand or be able to express what’s bothering them, making it difficult for doctors to react promptly. American scientists have demonstrated that Fitbit-type smart wristbands can signal the onset of complications several days in advance. This information is vitally important for doctors.
Scientists from Ann & Robert H. Lurie Children’s Hospital of Chicago and Northwestern University monitored 103 children for 21 days after surgery using smart wristbands. The devices measured heart rate, physical activity, and sleep. Subsequent analysis focused on circadian biorhythms, specifically how children’s physical activity and heart rate changed throughout the day. Researchers observed whether the body’s usual rhythm was disrupted. Based on these changes, they were able to detect complications in advance.
The algorithm predicted complications with 91% accuracy up to three days before diagnosis. The study included children aged 3 to 18 who underwent laparoscopic appendectomy. Some developed postoperative complications such as abdominal abscess, wound infection, or bowel obstruction. Researchers found that in children who developed complications, the rhythms of heart rate and physical activity were disrupted days before clinical symptoms appeared.
The algorithm, built on these biorhythms, predicted postoperative complications with 91% accuracy and had a specificity of 74%. This means the algorithm can indicate a problem several days before a diagnosis is made.
What are Biorhythms and Why Are They So Important?
Biorhythms refer to the cyclical variations in physiological processes throughout the day. For example, activity and heart rate increase during the day and decrease at night. After surgery, the body needs time to restore these rhythms, and if this process is hampered, it may indicate a complication.
“Children often find it hard to tell us when something is bothering them. The data from the wristband allows us to notice this in time, even before symptoms are visible,” says Arun Jayaraman, one of the study’s authors.
The System in a Real Clinical Setting
According to the study authors, the method based on Fitbit data provides doctors with an unbiased, daily picture of the patient’s condition. This is especially important when a child has already been discharged home from the clinic. The algorithm also works even when data is incomplete, which is common in real-world conditions.
The researchers identified six key biorhythmic indicators that can help assess a patient’s condition. These include step count, length of active periods, heart rate variability, and others.
The study’s authors plan to test the methodology in various other cases, such as monitoring oncology surgeries, orthopedic interventions, or chronic diseases. The idea is for smart wristband-based methods to become a part of routine clinical practice in pediatric medicine.
Reference
Hua, R., Carter, M., O’Brien, M. K., Pitt, J. B., Kwon, S., Manworren, R. C. B., … & Jayaraman, A. (2025). Biorhythms derived from consumer wearables predict postoperative complications in children. Science Advances, 11, eadv2643.
