Description:
Gastrointestinal bleeding is an ominous complication associated with 5-10% mortality.
Various methods have been developed for endoscopic control. (pause)
Clips, cautery, APC, and injection therapy have been useful with good efficacy. Using principles established by these tools future devices may better address current limitations by enhancing tissue capture and providing greater compressive forces.
Several novel endoscopic devices are under development may lead to improved endoscopic outcomes. These include memory clips, flexible suturing devices, high compression cautery, injectable polymers and telecommunicating biosensors.
We first discuss specialized clips.
Citinol clips have been used in experimental bleeding models. These are cut by electrical discharge machining and are mounted in a loaded position on the endoscope tip. These capture large amounts of tissue and achieve compression with serosal apposition.
Other developments have lead to flexible sewing tools.
This device has 4 degrees of freedom with articulating jaws that pass a barbed one-way locking suture preventing tissue from moving retrograde once acquired. This trans-oral device could find clinical application for hemostasis and closure of perforated ulcers.
Another flexible device under development for hemostasis are high compression endoscopic bipolar forceps. Insulation between conductive plates and jaws prevent radiation of heat and allow for trans-endoscopic sealing of large blood vessels. Applicable to future natural orifice surgery, this device may prove useful for advanced intralumenal procedures.
EUS directed polymer injection may allow temporary hemostasis in massive hemorrhage when visualization is not possible. Thermo-sensitive reverse phase polymers rapidly transform from a liquid into a gel-plug at body temperature as seen in this demonstration.
We introduce a novel hemostatic method using EUS-guided intravascular polymer injection in porcine bleeding models.
Here the gastroepipolic artery is carefully isolated from the greater curvature. It is transmuraly fixed within a gastric serosal envelope. Once the gastric walls are approximated, an endoscope is passed to inspect the vessel… noted here to be pulsating. The pigs were maintained on anticoagulation throughout the procedure.
Endoscopic ultrasound with M-mode identifies the Celiac artery. A 19 gauge needle is passed and radiocontrast injected to confirm the celiac artery extension into the gastroepiploic.
Following contrast injection the vessel is ligated using forceps inducing hemorrhage.
Subsequently using endoscopic ultrasound the reverse phase polymer is injected into the celiac artery. Under careful inspection the polymer can be seen propagating within the vessel, accumulating at the intragastric portion.
Hemostasis is endoscopically visualized and cessation of flow confirmed by Doppler EUS.
Dissolution of the temporary plug allows flow to resume after 8-16 minutes. Similar results were noted with our colonic bleeding model
This new endoscopic method of temporary hemostasis does not require direct visualization of the bleeding site and may provide more time for thorough endoscopic evaluation and definitive treatment.
This bleeding sensor, placed endoscopically, communicates critical information wirelessly via internet or mobile phone
The sensor was attached to gastric mucosa via clips. Bleeding was induced with immediate detection by the sensor and a wireless alert was sent to a cell phone.
In a porcine model mimicking lower or occult GI bleeding multiple sensors were placed in order to localize a source.
Similar to that gastric bleeding model an arterial source was attached to the colonic mucosa and bleeding was induced.
Sequential activation of the sensors was able to localize the bleeding segment. These new hemostatic devices may extend endoscopic therapy to new populations and improve outcomes in the management of GI bleeds.
Contributed By:
Sohail N. Shaikh, MD, Brigham and Women’s Hospital
Marvin Ryou, MD, Brigham and Women’s Hospital
Dan E. Azagury, MD, Brigham and Women’s Hospital
Christopher C. Thompson, M.D., Brigham and Women’s Hospital
