Page 35 - Journal of Special Operations Medicine - Fall 2014

Crystalloids—Plasma-Lyte A veins and even 7.5% HTS has been found to cause os-
159
Plasma-Lyte A has a neutral pH (7.4), an osmolarity of teomyonecrosis when given intraosseously. HTS 5%,
295mOsm/L, and no calcium, in contrast to LR, which which is FDA approved, also has the advantage of de-
has a lower pH, is slightly hypotonic (an osmolarity of creasing inflammatory response compared with stan-
273mOsm/L), and contains calcium. The cost of Plasma- dard crystalloid solutions and the ability to decrease ICP
156
Lyte A from one vendor was $9.99 for a 1000mL bag, without causing hypotension. 159
but purchased in larger quantities, it is only minimally
96
more expensive than LR. Plasma-Lyte A was compared HTS has been shown to be effective as an initial resus-
with NS in a study of 46 trauma patients and was associ- citation fluid, 163–165 but since HTS is a crystalloid, its ef-
ated with improved acid-base status and less hyperchlo- fects when used alone (as opposed to being combined
remia at 24 hours post-injury, although no improvement with a colloid) are short-lived.
157
in survival was found in this small study. This fluid
is approved for use with blood and blood products, Bulger and her coauthors performed a randomized con-
whereas LR is not recommended because the calcium trolled trial to examine the effects of 7.5% HTS compared
in LR interacts with the components of RBC units and with 7.5% HTS with dextran and compared with NS.
157
may cause the blood to coagulate. At present, there is The 853 study patients were all hypotensive from trauma
less published evidence with Plasma-Lyte A than with (62% blunt; 38% penetrating). Study fluids were admin-
166
LR, but in an observational study of 30,994 patients istered as a 250mL bolus by prehospital providers.
who received NS during major surgery compared with No difference in 28-day survival was found between the
926 patients who received Plasma-Lyte A or Plasma- three study groups.
Lyte148, the patients who received Plasma-Lyte A had a
lower incidence of postoperative infection, renal failure Dubose and his colleagues performed a prospective ob-
requiring dialysis, and the need for blood transfusion. 158 servational study of 51 trauma patients who received
500mL of 5% HTS with a matched cohort of trauma
Crystalloids—HTS patients who did not receive HTS but were resuscitated
Volume resuscitation with HTS would seem to be an with other crystalloids and blood products. HTS pa-
attractive option because the greater oncotic pressure of tients were observed to have elevated serum sodium for
the hypertonic sodium solution allows for greater intra- several days without any adverse effects associated with
vascular expansion than would occur with an equiva- this elevation. There were no differences in coagulation
lent volume of NS. A 250mL bolus of 7.5% sodium parameters or mortality. 162
chloride solution increases the intravascular volume
by approximately twice the infused amount. The ad- HTS has been shown to both decrease cerebral edema
ditional volume comes from the extravascular and in- and increase plasma volume in combined TBI and hem-
127
tracellular fluid spaces. HTS also reduces the body’s orrhagic shock. A 2004 report in JAMA studied 229
167
inflammatory response compared with infusion of iso- TBI patients who were hypotensive and comatose and
tonic crystalloids. 159 compared the effects of a 250mL bolus of either 7.5%
HTS or LR in addition to conventional fluid resuscita-
The 1999 Institute of Medicine recommendations for tion protocols used by paramedics. There was no effect
treatment of shock were that (1) no fluids be provided on either survival to discharge or neurological function
to casualties whose hemorrhage is controlled and who at 6-month follow-up. Two points about this study
168
are not in shock; (2) for casualties in shock from hemor- are worthy of note: (1) it was again done with 7.5%
rhage that has been controlled, 7.5% HTS be adminis- HTS, which is not FDA approved and thus not available
tered via the tibial intraosseous route as a 250mL bolus, to combat medical providers; and (2) the patients in this
to be followed by a second 250mL bolus if evacuation study also received other crystalloid and colloid fluids in
to definitive care is delayed; and (3) for casualties in the prehospital phase of care, which make understand-
shock from hemorrhage that has not been controlled, ing the impact of the HTS versus the LR more difficult.
the treatment is the same as for controlled hemorrhage HTS 3% has also been shown to be useful as an adjunct
shock. This recommendation has been echoed by oth- to improve primary fascial closure rates after damage
160
ers but remains problematic in that 7.5% HTS is not control laparotomy. 169
161
approved by the FDA and therefore cannot be placed in
the military logistics system. In a review of HTS for the USAISR Fluid Resuscitation
Conference, Coimbra stated that, due to the paucity of
Most of the human trials that have been conducted with studies examining small-volume 3% and 5% HTS use in
HTS have used the non–FDA-approved 7.5% concen- resuscitation from hemorrhagic shock, additional stud-
tration. 159,162 HTS 10%is highly irritating to peripheral ies are needed before this option can be recommended. 170

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