Page 130 - Journal of Special Operations Medicine - Spring 2016

replace water and electrolytes lost through sweating and shock with penetrating trauma to the chest and abdo-
urine, unless the patient has a condition that specifically men is appropriate with 1- to 2-hour evacuation times
requires large-volume continuous infusion therapy (e.g., from point of injury to damage control hemostasis. In a
burns, crush injuries, rhabdomyolysis). Complications of PFC situation, evacuation may be delayed for hours to
large-volume crystalloid resuscitation include compart- days. Maintaining a patient in a hypotensive state be-
ment syndromes, acute respiratory distress syndrome, yond the Golden Hour puts the patient at risk for end-
and dilutional coagulopathy. In addition, NS can cause organ injury, reperfusion injury, and a worsening shock
hyperchloremic acidosis in large-volume resuscitation. state from compensated, to decompensated, to refrac-
tory. We recommend FWB as the fluid of choice for pa-
Despite these cautions, crystalloids are not the enemy. tients in hemorrhagic shock.
They are first-line therapy in expanding plasma vol-
ume in septic shock. Also, in the initial response to a To mitigate these risks in the PFC environment, we rec-
hypotensive trauma patient, a careful provision of crys- ommend the provider aim for a “low-normal” perfusion
talloids remains a first-line strategy to expand plasma state defined as any one of the following: mean arte-
volume, optimize organ perfusion, and reduce the risk rial pressure (MAP) of 55–65mmHg, 13–15 adequate urine
for hypovolemic shock, compounding the inflammatory output (0.5mL/kg/hr) or adequate mentation (though
response to tissue injury. caution must be taken because mentation will be pre-
served at the expense of all other systems and vital or-
The differences between crystalloids are as follows: gans). Although this recommendation is greater than the
40–60mmHg MAP referenced in discussions of hypo-
• NS is an unbalanced crystalloid with a supraphysi- tensive resuscitation, 55–65mmHg is still a low-normal
ologic concentration of chloride, which can produce target that will minimize clot disruption and coagulopa-
a hyperchloremic metabolic acidosis in larger infu- thy in hemorrhagic shock while providing adequate tis-
sions. Increasing evidence shows that this worsens sue perfusion in all shock states.
inflammation and decreases kidney function. One
11
advantage of NS is its compatibility with many IV Resuscitation goals are important because they prompt
medications and blood transfusions. earlier provider responses, but beware of “chasing num-
• LR is a slightly hypotonic solution that has a minimal bers” in patients who have normal mental status and
effect on pH. It is referred to as a balanced crystal- adequate UOP. The goal of resuscitation is to treat the
loid because of the presence of organic anion (lactate) patient, not achieve a certain number. Patients may have
and lower chloride. The lactate component was once adequate organ function and circulation below a MAP
thought to be harmful, especially in critically ill pa- of 55mmHg. This “low normal” resuscitation strategy
tients with lactic acidosis. Research found that the d- is for patients in hemorrhagic shock only. Do not apply
isomer of lactate was proinflammatory, but that the this strategy to patients with other etiologies of shock.
l-isomer has beneficial immunomodulatory proper-
ties. The form of lactate currently used in LR is either Recommended Strategy for
l-lactate or a mixed l- and d-lactate form, both of Fluid Therapy in PFC
which have less toxicity than d-lactate. LR’s mild
12
hypotonicity makes it a less ideal fluid for patients The selection of maintenance or resuscitation (bolus)
with cerebral edema; in these cases, NS or Plasma- fluid should be guided by the patient’s clinical condi-
Lyte A would be recommended, if available. tion. If the patient is unstable with inadequate intravas-
• Plasma-Lyte A injection solution is an isotonic solu- cular volume, resuscitate with bolus fluid. If the patient
tion that can slightly raise a patient’s pH in larger is stable with adequate intravascular volume, provide
infusions. Plasma-Lyte A is compatible with blood maintenance fluid. A general target is to achieve a UOP
transfusions and with many IV medications. Plasma- of 0.5mL/kg/hr. Goals of UOP up to 1mL/kg/hr may be
Lyte A costs approximately 1.7 times more than NS advised by telemedicine consultation for specific condi-
and is generally considered equivalent to LR as a re- tions such as significant crush injury.
suscitation and maintenance fluid, though it is less
prevalent in the US medical supply system. Accurate measurement of UOP will most likely require
Foley catheterization in critically ill patients. In complex
Resuscitation Goals for cases such as burns, we recommend dumping the urine
Hemorrhagic Shock in a PFC Environment from the collection bag into a specimen cup or other
Robust medical evacuation infrastructure in Opera- receptacle every 60 minutes to accurately measure the
tion Enduring Freedom allowed close adherence to the hourly output. Simply estimating UOP in a large Foley
Golden Hour for damage control surgery. The permis- catheter collection bag may not be precise enough, since
sive hypotension strategy for patients in hemorrhagic the difference of 10mL may necessitate an increase or

114 Journal of Special Operations Medicine Volume 16, Edition 1/Spring 2016