Page 60 - Journal of Special Operations Medicine - Fall 2014

presented with cardiogenic shock, with right ventricular migration into critical end organs. However, it is the
failure, severe inferior left ventricular wall hypokinesia, consensus of the authors that the risk is judged to be
and pericardial tamponade. A severe consumptive co- very low based on the following facts:
agulopathy was already present at admission. The bleed-
ing rate was excessive, with 1260mL of blood during the 1. The cumulative experience from many decades of
first 15 minutes. After failure to control bleeding with chitosan research in science and medicine.
traditional methods, Celox Gauze was packed on the 2. The tissue adhesion (nonprocoagulant) mechanism
sternal edges and pericardial cavity to control hemostasis of action exterior to the damaged artery.
and was left in place for 36 hours. Coagulation param- 3. The biodegradation and bioabsorption properties.
eters improved significantly over the first 36 hours. 4. The knowledge gained from multiple preclinical
(normal and coagulopathic) animal studies.
Based on these cases reports of both external and inter- 5. Clinical case series of chitosan-based agents (granu-
nal application of chitosan-based dressings and agents lar) and dressings (gauze) with external application
in normal and coagulopathic patients, they appear safe by numerous NATO combat medical personnel from
to use on a long-term basis up to 72 hours in the abdom- the battlefield to obstetric use to control severe co-
inal cavity. However, with very few studies of long-term agulopathic vaginal postpartum hemorrhage as well
hemostatic efficacy for external use, this topic warrants as surgical (off-label internal) application in the op-
further investigation. erating room. There have been no complications re-
ported for long-term application of Celox Gauze in
both external (48 hours) and internal (liver lacera-
Chitosan and Allergic Reaction
tion) application (<14 days internal).
Because chitosan particles are derived from the exoskele-
ton of crustaceans (e.g., crabs and shrimp), justified con- It is the consensus of the authors that the cumulative
cern has been raised about allergic responses to chitosan evidence suggests that there is added benefit in using ev-
application to humans. Waibel et al. evaluated the idenced-based mucoadhesive dressings and that further
72
safety of a chitosan bandage in shellfish allergic subjects. safety testing is not required for Celox Gauze and Chi-
Participants who demonstrated specific shellfish IgE un- toGauze. However, it is still imperative that any new he-
derwent an allergy challenge. Nineteen participants were mostatic technology developed for combat casualty care
enrolled and 10 completed the study. Nine (90%) re- be initially evaluated for efficacy and safety, particularly
ported a shrimp allergy history and five (50%) reported when there is no evidence from clinical application and
multiple shellfish allergies. All participants completing case reports.
the study had positive skin prick test (SPT) and serum
Immunoglobulin E (IgE) testing to at least one shellfish;
eight (80%) had shrimp positive SPT and ten (100%) Conclusion
demonstrated shrimp-specific IgE. All participants toler- No current hemostatic agent or dressing has proven to
ated the HemCon Bandage without reaction. No other be ideal for all trauma scenarios in normal and coagulo-
studies using chitosan bandages in animal or prehospital pathic casualties. However, this review of animal studies
studies have reported any allergic response. and clinical case reports found that Celox Gauze and
ChitoGauze are as efficacious as Combat Gauze. These
Despite the efficacy and safety evaluations to date, par- chitosan-based dressings were not statistically differ-
ticularly with chitosan-based products, and based on ent than Combat Gauze for most outcome measures.
supporting clinical case reports, a question about safety Many studies revealed that chitosan dressing had strong
may still linger. Are these current FDA-approved third- trends toward faster hemostasis onset, less total blood
generation dressings safe for human use? Furthermore, loss, less fluid resuscitation requirements, and, for the
do all third-generation dressings need to be tested to most important primary end point: enhanced survival.
the same extent as conducted on Combat Gauze and Even though neither chitosan-based dressing have been
WoundStat application in swine as reported by Khei- tested in the same USAISR safety model as conducted
rabadi et al. ? To answer these questions specifically for on Combat Gauze and WoundStat, the animal studies
48
chitosan-based dressings, one needs to have an appre- and clinical cases series suggest a very low risk of throm-
ciation of the extensive history and safety of chitosan boembolic adverse effects. Preliminary data of external
particles studied in the biomedical field. Celox Gauze long-term application (at least 48 hours
and longer) suggest that it is effective and safe.
The safety of chitosan has been extensively addressed
(see earlier section “Chitosan-Based Agents and Dress- Consequently, after a decade of clinical use, there is added
ings”) but not definitively researched for the potential benefit and a good safety record for using chitosan-based
of chitosan particles resulting in emboli and particle gauze dressings. For these reasons, many specific US

52 Journal of Special Operations Medicine Volume 14, Edition 3/Fall 2014