Researchers from the Southern Medical University in China have developed a injectable surgical gel which can suture wounds without sticking to target tissue, effectively preventing postoperative adhesions.
Up to 90% of patients undergoing abdominal or pelvic surgery develop postoperative adhesions or scar tissue. Minimally invasive laparoscopic surgical approaches can reduce the severity of adhesions, but scar tissue still forms.
The cellular response to damage, even intentional, such as surgery to repair a problem, results in a cascade of molecules pouring into the site to heal the tissue. But the molecules, working quickly to close the wound, often push themselves too far and bind the wound to nearby healthy tissue. Depending on the location, the resulting scar tissue can cause chronic pain, intestinal obstruction, and even death.
The results of the Research scientists from Southern Medical University in China were published in the scientific journal Advanced Functional Materials.
Injectable surgical gel: this is how it works
According to the author of the article Yaobin Wu, Associate Professor, Guangdong Engineering Research Center for Translation of Medical 3D Printing Application, Southern Medical University in China, many anti-adhesive barriers are hydrogels inspired by mussels, marine animals that can adhere strongly to other materials.
Surgical hydrogels or gels can bind to moist tissue and are generally designed as double-sided adhesive materials, which increases the risk of postoperative adhesions. One class of hydrogels are asymmetrical, with only one adhesive side, which reduces the risk of adhesions, but their method of preparation makes them non-injectable and unsuitable for laparoscopic surgery, explained Professor Wu.
“Alternatively, liquid or glue release materials are injectable and can be easily administered during minimally invasive surgeries, but are often moved and diluted in the dynamic, moist physical environment of surgical sites.Wu said, noting that their composition can also trigger a molecular response that promotes the formation of adhesions.
“We have decided to design and prepare an injectable barrier with superior tissue retention properties capable of preventing the formation of adhesions following minimally invasive surgical procedures “, continued the scientist.
Previous research has suggested that polyanionic ligands, molecules that bind and render ineffective many types of other molecules, combined with thehyaluronic acid, a sticky molecule that plays an important role in the support network of all animal cells, could create an effective injectable surgical gel.
“However, there has been no report on the design of an injectable and asymmetric adhesive hydrogel based on a polyanionic ligand that could prevent aggregation of scavenger receptors and can be administered concurrently during the minimally invasive surgical procedure to prevent adhesion formation.Wu specified.
The researchers formulated such a hydrogel, dubbed HAD, with a photocurable breakthrough. When it was injected, the side of the hydrogel that was not touching the wound was treated with ultraviolet light for 3-5 seconds. Similar to its function in a gel manicure, UV exposure dried the hydrogel and prevented it from sticking elsewhere.
The compound was shown to be compatible with human cells, so the team tested HAD surgical gel in rat and rabbit surgeries. In rats that received HAD, in contrast to the ligand-free or pure saline versions of the hydrogel, most of the inflammation subsided and there were no noticeable adhesions 14 days after surgery. Critically, Wu said, the mortality rate in the non-HAD recipient groups was about 30-50 percent, while the HAD recipient rats survived.
The same results were made in surgery on rabbits.
“The results indicate that this injectable HAD surgical gel formulation is suitable for administration during a laparotomy to form an instant non-stick barrier in situ with good wound healing effects.”Wu said.
“Our team’s mission is to build a bridge between the gap between biotechnology research and clinical applications”, said Professor Wenhua Huang, director of the Research Center. “We believe that the administration of this injectable HAD hydrogel with controllable asymmetric adhesive properties can be easily integrated into laparoscopic surgeries in clinical use.”
An adhesion is a band of scar tissue that binds two parts of the tissue that are not normally joined togetherAnd. Adhesions may appear as thin sheets of fabric similar to plastic wrap or as thick fibrous bands.
Adhesion develops when the body’s repair mechanisms respond to any tissue disturbance, such as surgery, infection, trauma, or radiation, resulting in inflammation. Although adhesions can occur anywhere, the most common locations are within the abdominal cavity, pelvis, and heart.
Abdominal adhesions are a common complication of surgery, occurring in up to 93% of people who undergo abdominal or pelvic surgery. Abdominal adhesions also occur in about 10% of people who have never had surgery.Most adhesions are painless and cause no complications. However, adhesions cause about 60% of small bowel obstructions in adults and are thought to contribute to the development of chronic pelvic pain.
As for cardiac adhesions, scar tissue can form within the membranes surrounding the heart (pericardial sac), thus limiting heart function. Infections, such as rheumatic fever, can lead to adhesions on the heart valves and can lead to decreased heart efficiency.
Adhesions develop as the body tries to repair itself. This normal response can occur after surgery, infection, trauma, or radiation. The repairing cells inside the body cannot tell the difference between one organ and another. If an organ is repaired and comes into contact with another part of itself, or with another organ, scar tissue can form to connect the two surfaces.
For all these reasons, researchers at Southern Medical University in China plan to continue studying and testing the clinical value of the HAD surgical gel, with a specific focus on how the compound can help heal chronic wounds and prevent adhesions in a variety of diseases.
#Injectable #surgical #gel #prevent #scar #tissue