Patients take center stage during surgery. Their treatment should be as gentle and effective as possible, which is why there is a trend towards minimally invasive surgery (MIS). But minimal procedures require better supporting technologies. The hybrid operating room combines surgery and imaging systems and increasingly replaces conventional open surgery approaches with MIS.
The continued development of both minimally invasive procedures and imaging technologies led to the development of the hybrid operating room – it combines a conventional operating room with an imaging system – MRI, CT scan or angiography systems. This hybrid operating room makes it possible to simultaneously reach a diagnosis and provide treatment during surgical interventions. "This combination opens up new therapeutic possibilities and treatment options. It ultimately also results in a corresponding benefit for patients," explains Professor Bulitta, Director of the Institute of Medical Technology at the East Bavarian Technical University of Applied Sciences Amberg-Weiden. Besides, there is still the option to immediately switch over to open surgery from a minimally invasive procedure if necessary. "Both – interventional technique and open surgery – not only provide the highest safety, but also flexibility regarding the type of procedure," says Prof. Butter, Head of Cardiology at the Brandenburg Heart Center. In a few short years, hybrid operating rooms will become the standard, particular in the field of vascular surgery, which currently utilizes this type of OR the most. That’s why the hybrid OR plays an important role, also when it comes to patient safety and competitive ability.
The imaging system – typically an angiography system at this moment in time – is the heart of a hybrid operating room. "A hybrid OR has the advantage, that it enables optimal imaging in an operating room. There is a high-end X-ray system, which can make angiographies. These can be fused with others, preoperative images, for example of a CT or an MRI," describes Prof. Butter. There are many available options; a choice should be made based on spatial and financial feasibility as well as clinical requirements.
Generally, there are mobile and permanently installed angiography systems. The major advantage of mobile systems is that they are not bound to an operating room and can be flexibly used based on the need. Due to financial reasons, this offers an alternative to expensive, permanently installed systems, especially for smaller hospitals. Having said that, one drawback of these mobile systems is the lower image quality due to lesser tube performance and a low refresh rate. This is a significant limitation, in particular in the case of endovascular interventions where the tiniest of vessels need to be illustrated. Another downside with mobile C-arms is overheating during longer procedures. The systems quickly reach their maximum capacity during intricate surgeries and most notably with obese patients.
There are different versions of permanently installed systems for hybrid operating rooms: floor-mounted systems, ceiling-mounted systems with an extra-wide or standard track system, angiography systems installed on a mobile platform, biplane systems that make it possible to generate images simultaneously on two imaging planes as well as floor-mounted angiography robots. All systems differ in installation effort, required space, hygiene requirements and cost.
The choice of the angiography system also determines spatial planning as well as structural measures. In its guidelines, the German Society of Cardiology – Heart and Cardiovascular Research, recommends a room size of at least 60 square meters. Depending on the respective configuration, more space might be needed for the room to reach full capacity and for OR staff not to hinder each other or be impeded by technology. The floor-mounted system uses the least amount of space; a ceiling-mounted angiography system needs more space while a floor-mounted angiography robot requires the most space.
A hybrid operating room is an enormous investment; its acquisition alone costs between one and two million Euros; added to this are high remodeling and maintenance costs. On the one hand, the economic benefit is reflected in the increased demand for intricate surgeries. On the other hand, surgery durations, as well as hospital stays for patients, are shorter thanks to gentler surgery methods. In addition, intraoperative imaging also facilitates immediate quality assurance which results in a reduction of errors.
Two aspects are especially important when building and utilizing the hybrid operating room. First, progressive planning is essential; and adequate time and resources should be spent during the planning stage. To ensure the best possible utilization at a later point, all parties involved need to be included in the run-up. Next to anesthesia, perioperative care, technology and construction management, this also includes all medical specialties that plan on using the hybrid operating room at a later date. Meanwhile, many manufacturers provide a specific planning software to adequately design the structure with the help of 3D images.
Secondly, the hybrid operating room needs to be fully utilized because this lets hospitals generate sales that obviously don’t materialize if the OR remains empty. Training the staff is also essential, aside from smooth workflow management. "Oftentimes, the disciplines that utilize a hybrid OR stem from the surgical field which is generally not very experienced with permanently installed angiography systems. The staff needs to be trained as quickly as possible for the installation to be profitable and optimally utilized," explains Dr. Peter Belei, Advanced Clinical Applications iXR, Philips GmbH Market DACH. Another aspect is radiation protection. A fixed angiography system provides a higher level of image quality than a mobile C-arm but might correspondingly also cause increased x-ray exposure. This is a problem for the staff that is exposed to x-rays on a daily basis. "The hospital needs to take all safety precautions for the hybrid operating room to be efficient while not endangering the team," says Belei.
Hybrid operating room manufacturers also face challenges. "It is difficult for manufacturers to integrate all the technologies needed in the hybrid OR and utilize the sparse space as efficiently as possible," explains Belei. "The system should also be integrated into the already existing procedures, eliminating the need for OR staff to completely change the usual operations."
The future belongs to minimally invasive surgery and therefore also to intraoperative imaging as well as hybrid operating rooms. For cost reasons, it is no longer just the cardiovascular disciplines that utilize hybrid ORs. Other subdisciplines like neurosurgery, traumatology or orthopedics can also benefit from 3D imaging and the higher image quality of an angiography system. "The system needs to be seamlessly integrated into the various operating procedures of the different disciplines in the OR, ranging from orthopedic to vascular surgeons. It needs to have all necessary functions for the various disciplines to operate optimally," explains Belei. For Butter the trend also is in the interdisciplinary utilization of the hybrid OR: "All the different disciplines perform more and more complex procedures. Thus, high-end imaging equipment makes perfect sense. Probably, the future hybrid OR will provide optimal conditions, so that different disciplines will be able to use the room."
The technological development increasingly moves towards the area of image correlation. Data from various modalities such as ultrasound, x-ray, and MRI is merged and complements one another, thereby reducing x-ray exposure and using minimum amounts of contrast media. The integration of OR systems with the various devices will also play an increasing role in the future and present a challenge for manufacturers and users. At the moment, all manufacturers have their own operating philosophy the OR staff needs to understand. In the future, this should be different to where the different technologies communicate with each other and equipment can be used effectively. "Even though these ideas have already been initiated, they will continue to accompany us over the next few years and perhaps even over the next decade," explains Belei with a keen eye towards the future that has already begun.