Top Stories - Posted by Phil Sneiderman-JHU on Friday, August 17, 2012 10:19 - 3 Comments
Future of suture: Pliers meet hole punch
JOHNS HOPKINS (US) — A tool that’s a cross between pliers and a hole punch may keep surgeons from puncturing internal organs when closing incisions.
The device, dubbed FastStitch, is also designed to prevent other dangerous complications that can occur after open abdominal surgeries for treatment of cancer, liver problems, and other common ailments. Up to 5 million such procedures are performed annually in the United States.
“We’re developing the future of suture,” says Sohail Zahid, leader of a team of eight Johns Hopkins undergraduate students that invented the disposable tool in a biomedical engineering class.
“We believe that if the FastStitch tool is used to close abdominal incisions, it will help in three important ways,” he adds. “It will help surgeons by making the closure process simpler and safer. It will help hospitals by reducing costs.
“And, most importantly, it will help patients by reducing post-operative complications.”
If abdominal incisions are not closed properly, a patient can develop complications such as infection, herniation, and evisceration, all of which require additional treatment and in some cases, more surgery.
Just one of these complications—herniation, in which intestinal tissue protrudes through the abdominal wall after a muscle layer splits apart—leads to $2.5 billion in additional costs annually in follow-up treatment and medical malpractice expenses, the students said.
The student team was asked to design and test a tool that would improve the way surgeons stitch together the strongest part of the abdomen, the muscle layer called the fascia, located just below the skin.
“Doctors who have to suture the fascial layer say it can be like pushing a needle through the leather of your shoe,” team member Luis Hererra says. “If the needle accidentally cuts into the bowel, it can lead to a sepsis infection that can be very dangerous.”
To prevent this, the students designed FastStitch so that the suturing needle remains within the jaws of the stitching tool and is not exposed to nearby organs.
“You place the fascial layer between the top and bottom arms of the device,” Zahid explains. “Then, as you close the arms, the spring-loaded clamp is strong enough to punch the needle through the fascial layer. When this happens, the needle moves from one arm of the tool to the other.”
The device also has a visual guide to ensure that stitches are spaced evenly, the proper distance away from the incision and from one another. The hand-size, pliers-like shape was chosen because it would feel familiar to surgeons and require less training.
The tool is constructed mostly of ABS plastic, so that the instrument can be inexpensive to manufacture and discarded after one use.
Physician Hien Nguyen, an assistant professor of surgery in the Johns Hopkins School of Medicine, served as the students’ clinical advisor during the development of FastStitch.
“Just about every major operation in the chest and abdomen requires a large cut to be made through the muscle layers,” he says. “If these layers are not brought back together evenly, complications can occur.
“This device allows the surgeon to bring the muscle layers back together evenly, safely, and quickly, and this can lead to better outcomes and fewer complications.”
Team members have obtained preliminary patent protection. All eight students are listed as co-inventors, along with Nguyen and Johns Hopkins graduate student Adam Clark. The students have formed a Baltimore company, Archon Medical Technologies, to conduct further research and development. Animal testing of the device is under way, and further testing with human cadavers is expected to begin later this year.
Source: Johns Hopkins University