Innovative Device and Mechanism
A remarkable advancement in medical technology offers hope for reducing excessive blood loss during surgical procedures by harnessing the power of nerve stimulation.
Researchers have developed a device that attaches to the ear and uses transcutaneous auricular neurostimulation, or tAN, to stimulate the vagus nerve, potentially enhancing the body’s natural ability to form blood clots.
The preliminary study, conducted on healthy volunteers and sponsored by the company Five Liters, provides intriguing evidence that stimulating the vagus nerve may trigger a process that promotes blood clotting.
According to Dr. Jared Huston, a trauma surgeon at Northwell Health’s Feinstein Institutes for Medical Research, this marks the first evidence in humans of what he describes as a “neural tourniquet,” a brain-mediated mechanism aimed at controlling bleeding.
Promising Early Findings
Should subsequent clinical trials confirm the efficacy of this approach in minimizing blood loss, it could transform preoperative methods, offering a safeguard against significant hemorrhaging during surgeries.
Approximately 1.5% of surgical procedures currently encounter complications related to excessive bleeding, an inherent risk across various types of operations.
Traditional strategies to manage this challenge have included sutures, bandages, and tourniquets, all intended to restrict blood flow to specific areas.
Huston emphasizes that preventing blood loss before it occurs is far more effective than addressing the problem after it arises.
Research into the vagus nerve’s role in blood coagulation dates back nearly two decades, stemming from its known ability to regulate inflammation.
This nerve, extending from the brain to various organs, governs the parasympathetic nervous system, a counterbalance to the fight-or-flight sympathetic response.
Initial animal studies conducted on mice and pigs showcased promising results, demonstrating that vagal nerve stimulation could indeed reduce bleeding from minor injuries.
The team dedicated nearly a decade to unraveling the underlying mechanics of this response.
Future Implications and Challenges
In earlier findings, Huston’s research group identified that stimulating the vagus nerve activated T cells within the spleen, an organ crucial for blood filtration and immune function.
Activated T cells were found to enhance platelet activation, a critical step in the clotting process.
The team even noted reduced bleeding in mice suffering from hemophilia, a condition that impairs normal clot formation, following vagus nerve stimulation.
To explore these findings in humans, Huston’s team collaborated with Five Liters to recruit a group of healthy participants for the trial.
Following 30 minutes of vagal nerve stimulation using an approved device targeting the auricular branch of the nerve behind the ear, blood samples were collected for analysis.
The results revealed increased levels of markers for platelet activation in the blood after stimulation, suggesting that this neural tourniquet pathway is indeed functional in humans.
This non-invasive method offers an exciting prospect for enhancing surgical safety and patient outcomes.
While the early results are promising, experts emphasize the need for further research to substantiate the effectiveness of vagus nerve stimulation in people undergoing surgery.
Professor Peder Olofsson of the Karolinska Institute in Sweden, who was not involved in the study, highlighted the importance of accurately assessing bleeding metrics, such as volume and duration, to demonstrate the clinical potential of this innovative approach.
The challenge of ensuring consistent physiological outcomes with non-invasive stimulators, unlike implanted devices, remains significant.
Despite potential risks often associated with nerve stimulation, Huston notes that this technique is already utilized in the treatment of conditions like epilepsy and depression.
If larger studies corroborate these encouraging findings, it may soon become standard practice for surgeons to employ brief periods of vagus nerve stimulation prior to operations, similar to the routine administration of antibiotics or pain relief.
The need for a method to prepare people for surgery and mitigate bleeding is considerable, and this cutting-edge approach could be the answer.
Study Details:
- Title: “Neural Tourniquet” via Vagus Nerve Stimulation for Hemostasis: Evidence for a Brain-Based Pathway to Reduce Bleeding
- Authors: Jared M. Huston, et al.
- Journal: Bioelectronic Medicine
- Publication Date: 2014
- DOI: 10.15424/bioelectronmed.2014.00006