Engineering and image-guided precision surgery are converging in a cutting-edge facility that features moving CT and MRI equipment shared between two surgical rooms designed to support both translational research and advanced clinical procedures. The new 13,000-sf addition, under construction at the Dartmouth-Hitchcock Medical Center in Lebanon, New Hampshire, combines imaging and surgical space for both human patients, as well as animal research subjects, in a single multi-use perioperative suite. The goal is to not only share expensive equipment resources between research and clinical applications, but also to create a space that can be used for reengineering better image-guided surgery techniques from the ground up.
“This is a collaborative multidisciplinary program that is designed to achieve great research benefits, and also very quick clinical outcomes,” says Gail Dahlstrom, vice president of facilities planning and management at Dartmouth-Hitchcock Medical Center.
The innovative facility came from an application submitted by a team representing Dartmouth Medical School, the Thayer School of Engineering, and the Dartmouth-Hitchcock clinical enterprise in response to an ARRA grant administered by the NIH.
“When it comes to image-guided surgery, we believe that we need to return to first principles and look at fundamental questions like: What is the best design for an implant? What is the best approach? This means that we’re really designing things from scratch as an engineering problem, rather than retrofitting current procedures with image guidance. And that requires a very unique facility,” says Sohail K. Mirza MD, chair of the Department of Orthopedics at Dartmouth Medical School.
Complex image-guided surgical procedures are useful for spinal or pediatric surgery and for treating brain cancer where removing even an extra centimeter of tissue could result in a loss of vision, memory, or sensation.
According to Dr. Mirza, the argument the NIH reviewers found compelling was that, while there are several intra-operative
“We suggested that a facility that had research as its primary aim could first allow experiments and innovations to take place, but secondly, evaluate them in a more directly objective way,” says Dr. Mirza.
While a perioperative suite that combines different imaging modalities and can be used for both clinical procedures and translational research holds considerable promise for rapidly developing new surgical approaches, it also presents significant design challenges. Chief among these is establishing adequate measures for preventing cross-contamination while also meeting complex safety and shielding requirements with intensive logistics and utility support needs.
The facility’s two operating rooms are separated by an equipment room housing a shared MRI mounted on a continuous overhead track that allows it to be easily moved from one OR to the other. This also means the floor of each room can be managed like a standard surgery space.
“It may sound straightforward in concept. But in real life, with a real patient, it’s not just a table where the MRI can move in and out. There are all kinds of tubes, warmers, anesthetic lines, IV lines, and a lot of people and equipment involved that have to be planned for,” says Dr. Mirza.
The moving MRI, which is made by IMRIS, is mounted on a continuous rail that requires a robust ceiling plenum and additional structural support below the floor-slab. The ceiling space also provides extensive boom-support for lighting and navigational camera systems as well as MEP distribution, while a mechanical room below the floor stores additional equipment.
“The distribution system has to navigate through a lot of complex pockets so Building Information Modeling (BIM) clash detection is very helpful, though nothing beats sitting down in multiple work sessions face to face to plan out these kinds of systems,” says Sho-Ping Chin, a principal at Payette in Boston and lead designer on the project.
Complex shielding requirements present an additional complexity. Because the
Eliminating Cross Contamination
Since the facility will accommodate both human patients and animal research subjects in a surgical environment, eliminating any potential risk for cross-contamination was top priority.
“We worked very closely throughout the entire process with the safety group, infection control, and the end-user to establish effective infection control protocols, including off-scheduling between patients and research subjects, completely separate access points and travel routes, and separate work zones within the surgery center,” says Chin.
Air flow is also a critical part of containment. When humans are in the suites they have positive pressure with laminar airflow over the table, but when animals are in their zone, the pressure is negative.
“We are using a series of digital differential pressurization sensors that are tied into the door control panels. So if the room has not reached the right level of pressurization, the doors won’t open,” says Chin.
Designing for the Unknown
The groundbreaking and logistically complex nature of the facility—which is scheduled to open in early 2013—has been a learning process for the entire team.
“Designing for an unknown future is incredibly challenging. If I had to do it over again, I would have built a much stronger contingency into the project throughout. Our initial contingency was a standard 13%, but the complexity of this project was so incredibly unknowable that I would probably double it, and keep one for both owner and construction until the very end,” says Dahlstrom.
Sho-Ping Chin also emphasizes the need to stay nimble and keep in mind that, with a project this complex, the parameters will continue to evolve even after documentation is complete.
“Most of these pieces of equipment are first of their kind and still under development as the project is being constructed so it’s important to anticipate formidable changes even during construction. You also want to build in a reasonable range of capacity and plan for future connectivity needs with extra electrical and data penetration panels because it will be extremely challenging to retrofit them through the shielding system,” says Chin.
“The Thayer School of Engineering is conducting a lot of research within Dartmouth-Hitchcock to develop new technologies that can be applied directly to things like breast imaging and other areas within the clinical enterprise. Over time we believe this facility is going to become a top national destination for services and training in really complex image-guided surgical procedures,” says Dahlstrom.
By Johnathon Allen
This report is based on a forum led by Dahlstrom, Chin, and Dr. Mirza at the Tradeline Academic and Medical Health Science Centers Conference in December, 2011.