Safety and efficiency with DORA in the operating theatre

Interventions & Care

Dr John van den Dobbelsteen is a biomechanical engineer at TU Delft. He has developed a Digital Operation Room Assistant (DORA) in collaboration with many partners, one of which is Dr Maarten van der Elst of Reinier de Graaf Hospital in Delft.

DORA aims to improve patient safety and efficiency in the operating theatre (OT). The project started in 2006 or 2007, when Emiel Verdaasdonk was a PhD student at TU Delft at Reinier de Graaf Hospital. Emiel performed an observational study, in which he videotaped about 30 gallbladder removal operations. To his surprise, there were small incidents involving medical equipment in almost every operation. “For instance, a specific instrument was missing or the proper connector wasn’t there. These problems could usually be resolved in a few minutes, but clearly it was inefficient. In rare cases, an accumulation of such minor incidents could result in a threat to patient safety.”


Expensive medical instruments are shared by multiple operation rooms, says Maarten van der Elst, surgeon at Reinier de Graaf Hospital. “By law, it’s the surgeon’s responsibility to make sure that all equipment is present and in good condition before starting surgery. This includes instruments, such as anaesthesia machines, laparoscopic equipment, lasers, and infusion pumps.” But in practice, it is not really feasible to inspect all the equipment and maintenance stickers every time. “So Emiel set out to compile a two-minute paper-and-pencil checklist to be completed before the start of surgery,” says Van den Dobbelsteen. “This worked very well; it halved the number of incidents. But it was yet another administrative procedure for the OT staff. So, we thought: we’re a technical university; we should be able to develop an automated checklist.”

Green screen

The team set out to develop a Digital Operation Room Assistant (DORA). In the new building of Reinier de Graaf, all eight operation rooms are equipped with an iPad that communicates with DORA. Surgical instruments have been equipped with a sensor that allows DORA to track their location. DORA is linked to the database of the hospital’s technical unit, so it also knows the equipment’s maintenance status. In addition, DORA knows which operations are planned for the day and which instruments are required. The iPad screen turns green if everything is in place and properly functioning before the start of surgery. If not, it turns red. “So, as a surgeon, I only need to check if the screen is green,” says Van der Elst. “Checking the screen and figuring out what’s wrong if it’s red, has become an obligatory part of theatre procedures.” The researchers have also applied buttons to the instruments. “Medical instruments may dysfunction for a very short period – a hiccup, as we call it,” says Van der Elst. “This should be communicated to the hospital’s technical unit, but that’s easily forgotten. Now, OT staff can simply press the button and specify the problem by typing a message to the technical unit on the iPad.” "Our hospital was audited in 2016 and the accreditation committee regarded DORA as a best practice; they stated that they were in love with DORA," says Van der Elst.

People from TU Delft think outside the box. By collaborating with medical specialists, they can create technical solutions of great clinical relevanceMaarten van der Elst, Reinier de Graaf Hospital

OT planning

A small company is now looking into the possibility of selling the DORA system to other hospitals. Meanwhile, the team continues to work on new functionalities. For instance, they are collaborating with the Eye Hospital in Rotterdam and Leiden University Medical Center to develop operating theatre planning functionalities. Maarten van der Elst explains: “Adequate planning is crucial to ensure efficient use of our operating theatres, but it’s hard to predict exactly how long an operation will last. This makes the job of the people in charge of planning extremely difficult: they continuously need to monitor the progress of multiple operations so that they know when the next patient can be prepared for surgery.”

The team is also developing smart sensors that register the use of instruments. As specific instruments are used during specific phases in the surgical procedure, this information can be used to monitor the progress of the operation. Connecting the smart sensors to DORA enables the system to continually update operating theatre planning and thus make the operation process more efficient. “For instance, in a gallbladder removal, an electrosurgical device is used to cut loose the gallbladder,” says Van der Elst. “This happens approximately ten minutes before the end of surgery. Dr Annetje Guédon has shown that the moment when this piece of equipment is activated is an excellent predictor of how long the operation will still take. Then it’s time to start preparing the next patient. We can use this to improve the flow in all our operating theatres.”


The researchers use algorithms to train DORA to recognise patterns and adjust its predictions accordingly. “We need to collect a lot of data to feed these algorithms,” says Van den Dobbelsteen. “To this end, we’re starting up a company. The combination of expertise from companies, hospitals and the technical university is very strong. At the university, we develop novel concepts. These are then tested in the real-life environment of the hospital. And a company can scale the system up, so that we obtain sufficient information to train the system. I’m also very grateful to the insurance company DSW, which has supported us by funding several PhD students since 2005.” Van der Elst adds: “Our collaboration is very pleasant. First, there was a lot of confusion about terminology, but we gradually started to speak each other’s language.”

Intelligent system

Ultimately, the team would like DORA to recognise risky deviations from regular operation procedure and alert theatre staff so that they can avoid adverse events. In the Netherlands, 1,000 to 2,000 patients die each year as a result of preventable medical errors. These tragic cases are usually the result of an accumulation of several small incidents. By combining a large amount of data of various sorts, DORA could detect such dangerous situations in the future. “This is the realm of ‘big data’,” says Van den Dobbelsteen. “We need to collect a lot of data and link up a variety of hospital systems to achieve this. This calls for both investment and collaboration; people all need to have the same goal. For instance, hospitals often use different software packages for theatre planning and for monitoring the maintenance status of their equipment. These systems are not linked, although this is often necessary if DORA is to perform well. Fortunately, hospitals that purchase a new system often want it to be able to communicate with DORA, so in a sense, our project encourages standardisation.”

Interview by: Linda van den Berg
Picture: Paul Riem