An early warning system for abdominal surgery complications

More than 330 million surgical procedures are performed worldwide every year. While the majority of patients are able to resume their normal lives without restrictions after surgery, many face post-operative complications. Major gastrointestinal surgery is particularly prone to complications due to leakage of abdominal sutures, which can cause the contents of the digestive tract to spill into the abdominal cavity. According to a Finnish study, more than 30% of all abdominal operations result in post-operative complications, with a significant number leading to mortality.

One reason for the high number of complications in complex abdominal surgery is the delay in detection by existing diagnostic methods. Current methods of post-operative monitoring are often time-consuming and labour-intensive. They are also inadequate at promptly detecting serious complications such as abdominal infections and even life-threatening sepsis.

The winning project of the Empa Innovation Award 2024, a prize for the best innovation and technology transfer project at the interdisciplinary research institute of the ETH Zurich Domain for Materials Science and Technology, has taken up the fight against these complications. The SensAL sensor detects post-operative complications early after abdominal surgery.

After surgery, wound secretions are drained through a tube fitted with the SensAL sensor. The sensor contains substrates for enzymes typical of the gastrointestinal tract. If these enzymes are detected in the wound fluid, the sensor reacts by changing colour, immediately alerting the nursing staff to a possible leak.

Because it is a chemical sensor without any electronics, it is cheap to manufacture and can therefore be used on a large scale. The prototype sensor has already performed well in initial laboratory tests. For further development and validation, the sensor is being tested in collaboration with several hospitals.