Page 55 - Journal of Special Operations Medicine - Summer 2016

Chlorhexidine is available in premixed applicators, often The WHO is also interested in alternatives to the tradi-
found in the clinic setting, but these may not be feasible tional methods described in this article. One potential
in the deployed setting as they would take up space and alternative is the solar-powered autoclave, which would
generate waste after use. It can be purchased commercially alleviate the need for electrical or fuel-powered auto-
in larger quantities in a 5% solution. The recommended claves by use of a solar panel to generate the necessary
concentration for skin antiseptic use is 0.05%, which can steam temperature. Once again, at the time of this pub-
be prepared by adding 10mL of the 5% solution to 1L lication, this technology is still in development.
of potable or previously filtered and boiled water. Once
mixed, the solution can be used for a maximum of 1 week.
Recommendations
2. Normal Saline: Normal saline (0.9%) is frequently Of the several alternative methods to process medical
used in the hospital and clinic setting for wound ir- equipment for reuse, we recommend the following:
rigation. This can be used in the field setting as well.
Normal saline that is placed in a 35mL syringe with a Sterilization should be the “gold standard.” Steam ster-
18- or 19-gauge angiocatheter produces 7 to 8lb/in of ilization by autoclave should be the primary means, and
pressure and is appropriate for wound irrigation. In this should be maintained at the Role 1 aid station or
the hospital setting, normal saline is commonly found higher level. If steam sterilization is not available, then
packaged in sterile 500mL or 1L intravenous (IV) bags. dry heat sterilization should be your first alternative.
In the field environment, however, IV fluids come at a
premium since you limited to what you can carry in or If steam or dry heat sterilization is not possible, then
what you have externally resupplied. For this reason, IV high-level disinfection by boiling water bath should be
fluids would be a waste of a limited resource if used for your first method. If this is not available, then chemical
wound irrigation. disinfection should be your next resort.

For purposes of wound irrigation only, normal saline When determining the many methods available for
can be made locally by adding 2 teaspoons (9g) of salt chemical disinfection, we believe that povidone-iodine
to 1L water that was previously boiled or otherwise (Betadine) solution is the best method as it is readily
made safe to drink. Further, it has been shown in sev- available in the proper concentration in the medical
14
eral studies that normal potable tap water had an equal, equipment sets. Hydrogen peroxide is the best second
and in some cases lower, rate of wound infection com- choice for chemical disinfection; however, the required
pared with irrigation with normal saline. 19–21 Therefore, concentration is not the same as found in the medical
copious amounts of potable water may also be used for equipment sets and will have to be purchased separately.
wound irrigation if no other agents are available. Bear
in mind that the above-mentioned studies were con- Dakin’s solution is the best third choice since it can be
ducted using tap water in the developed world that was made from simple commonly obtained items; however,
presumably safe to drink. In the deployed setting, any the immersion time limits its use as a true high-level dis-
water source that is potable and approved for consump- infectant (Table 1).
tion should suffice for wound irrigation.

Conclusion
Future Technologies
As medical providers deployed in the austere environ-
The Natick Soldier Center had been working on a light- ment, it is our responsibility to offer the same level of
weight sterilizer to potentially replace the bulky tradi- medical care that our soldiers would expect when not
tional steam autoclave currently being used in combat in the deployed setting. We are presented with a unique
support hospitals. The result was the development of challenge, especially when deployed beyond the reach
4
the Portable Chemical Sterilizer, or PCS. It weighs ap- of the traditional supply chain. These challenges are
5
proximately 20lb, costs less than $1000 per unit, and not typically presented to traditional medical units, and
relies on chemically generated chlorine dioxide for ster- therefore we must look for novel approaches to make
ilizations. It is about the size of a medium suitcase and is our equipment safe for reuse. These methods should be
claimed to be able to kill bacterial spores as well as other in as close proximity to the guidelines set forth by the
common pathogens. This poses a potential replacement CDC and OSHA as they apply to hospitals and clinics
for the standard field autoclave currently being used in in the United States, but they should be modified to
Special Operations Forces battalion aid stations; how- conform to the mission. For instance, the minor surgi-
ever, the patent has since been released to the commer- cal instrument set carried in the aid bag is not sterilized
cial industry, although at the time of this publication, it and sealed before use, and the traumatic nature of com-
had not been released yet for operational use. bat injuries hardly make them a sterile field in which

Field Sterilization in the Austere Environment 41