1. In Vitro Studies
|Standardized laboratory studies have been used to show the effectiveness of OMNI-STAT and Celox as hemostats. The time taken to form a good clot using freshly drawn blood was assessed and recorded. OMNI-STAT significantly reduced the clotting time compared with the control tests (30.5 secs vs 816.5secs, respectively). The clots were removed from the test article and photographed after 20 minutes, OMNI-STAT showed a robust gel-like clot. (Johnson et al, 2008)||
Blood clots after 20 minutes (Johnson et al, 2008)
|Studies examining the hemostatic effect of the chitosan derived dressing on coagulation of anticoagulant treated blood showed that hemostasis is largely unaffected by the presence of anticoagulants. Whereas anticoagulant treated blood showed significant delays in coagulation in the standard laboratory tests, the presence of chitosan derived material led to coagulation times similar to those seen in the non anticoagulant treated blood. In this model the heparinised blood clotted in 48s and warfarinised blood in <30s when in contact with OMNI-STAT granules. (Johnson et al, 2008).||
|OMNI-STAT was able to clot freshly drawn heparinized blood that has been cooled to a temperature of 56°F. The mean clotting time for the OMNI-STAT treated blood was 20 seconds, whereas control blood failed to clot within the 10 minute test period (Data on File).||
OMNI-STAT on hypothermic blood
2. In Vivo Studies
Kozen, et al 2008
A standard industry model of a complex groin injury with transection of the femoral vessels and 3 minutes of uncontrolled bleeding was created in 48 swine.
Results show that OMNI-STAT significantly improved hemorrhage control and survival.
Rall, et al 2013
In independent in-vivo test conducted, subjects treated with Celox (OMNI-STAT)* Gauze demonstrated the highest rate of observed survival with 90% when compared to the current standard of care, Combat Gauze demonstrated a 60% survival rate. Celox (OMNI-STAT) also has a substantial history of use on the battlefield (with conventional and special forces) and has repeatedly proven itself in austere settings.
The military's Committee on Tactical Combat Casualty Care (CoTCCC) has added Celox (OMNI-STAT) Gauze to its guidelines for control of hemorrhage as approved hemostatic agents for military-wide use.
*OMNI-STAT and Celox are brand names of equivalent proprietary chitosan technology. For more information on Military & Civilian use visit www.celoxmedical.com
Millner et al examined the effectiveness of two chitosan derived hemostatic agents (OMNI-STAT granules and OMNI-STAT Gauze) in a porcine model of major hepatic injury in the presence of impaired clotting (Millner et al, 2010).
Winstanley et al, 2018
A retrospective database analysis of 3792 cases of catastrophic hemorrhage in military major trauma patients on the battlefield was conducted. When comparing patients, 317, who had a hemostatic dressing applied (either Celox (OMNI-STAT), Hemcon or Quikclot) versus no hemostatic agent, results showed there was a 7% improvement in survival. Celox (OMNI-STAT) was the only individual hemostatic dressing that was associated with a statistically significant improvement in survival, which was most apparent in the more severely injured.
Snyder et al, 2013
The presence of devitalized tissue in wounds may impair the healing process and removal of this tissue promotes wound healing (Saap and Falanga, 2002). The removal of devitalized tissue can be achieved by debridement and sharp debridement removes this necrotic tissue down to the level of well-vascularized tissue (Fife et al, 2012). Sharp debridement can increase the risk of bleeding and this risk is exacerbated by the use of anticoagulants in the aging population where chronic wounds are particularly prevalent. Clinical evaluations have been reported demonstrating positive outcomes of using OMNI-STAT in providing effective hemostasis after sharp debridement, including patients receiving anticoagulants.
Open-label, controlled evaluation (n=40) evaluating chronic wounds of varying etiology with or without
concomitant use of anticoagulants.
|Snyder and Sigal (2013) reported on the results of an open-label, controlled clinical investigation designed to evaluate the hemostatic properties of the chitosan-impregnated gauze, OMNI-STAT, in patients with open wounds of various aetiologies (including diabetic foot ulcer and venous leg ulcer) post-debridement. Forty patients were recruited into the study (n=20, OMNI-STAT; n=20, standard of care). Both groups included a large proportion of patients on anticoagulant therapy (15/20 OMNI-STAT, 16/20 control). After debridement, excess blood was wiped away and the wound was then treated with the OMNI-STAT or the control gauze followed by pressure for 2 minutes. The dressings were left in place for 7 days and then removed at a follow-up visit after being saturated with saline for five minutes. The primary endpoint in the study was the time required to achieve hemostasis with secondary endpoints being an assessment of the patient’s pain levels at the start and end of the treatment and an assessment of the wound bed.||
Time to hemostasis (minutes) (Snyder and Sigal, 2013)
|The mean time hemostasis in the OMNI-STAT treated group was 1 minute 19 seconds compared with 5 minutes and 19 seconds for the control group (p<0.0001). The quality of the granulation tissue of the wound after 1 week was significantly improved in the OMNI-STAT treated group (OMNI-STAT group: 18/20 improved, none deteriorated; control group: none improved, 4/20 deteriorated; p<0.05). Pain scores in the OMNI-STAT group were consistently lower compared with the control group upon application, during application and on dressing removal after one week. The authors conclude that, as well as promoting hemostasis leading to reduced treatment time, the OMNI-STAT provided a moist wound environment and improved the quality of the wound granulation tissue. The establishment of a moist environment may be due to the absorbent nature of the chitosan granules component of OMNI-STAT. The authors suggest that the use of chitosan-impregnated hemostatic dressings may lead to an alteration in clinical practice, allowing for the rapid control of bleeding after wound debridement in patients with chronic wounds despite the prevalence of anticoagulants.||
Tissue quality after 1 week (Snyder and Sigal, 2013)
Thibodeaux et al, 2020