(1) One thousand milliliters (ml) of Ringer's lactate (about 2.4 pounds) will
expand the intravascular volume by 200 to 250 ml within one hour. Sodium is the
primary osmotic agent in RL and will not remain in the vascular system very long. It
diffuses out into the interstitial space and eventually into the intracellular space. This
fluid is better for treating dehydration.
(2) Five hundred milliliters of Hextend (about 1.3 pounds) will expand the
intravascular volume by 800 ml within one hour and will sustain this expansion for up to
eight hours. Hextend contains large sugar molecules that remain in the vascular
system for a much longer time than RL. Hextend also pulls additional fluid from the
interstitial spaces and holds this fluid in the vascular space for a longer period of time.
Hextend is better for treating hypovolemia secondary to blood loss than RL.
d. Resuscitation Indicators.
(1) The blood pressure is commonly used to determine who needs fluid
resuscitation. However, stethoscopes and blood pressure cuffs are rarely available or
useful to the front line soldier medic in the typically noisy and chaotic battlefield
(2) A palpable radial pulse and normal mentation (mental ability) are
adequate and tactically relevant resuscitation endpoints to either start or stop fluid
resuscitation. Both can be adequately assessed in noisy and chaotic situations without
(3) Casualties should only be resuscitated to a systolic blood pressure of 80
millimeters of mercury (mmHg). This blood pressure is adequate to perfuse all vital
organs and, yet, not high enough to cause a possible re-bleed of a vessel that has
already clotted. Re-bleeding can occur with a systolic blood pressure as low as
approximately 93 mmHg.
(4) The systolic blood pressure may be approximated by palpating pulses in
(a) A palpable carotid pulse indicates a systolic blood pressure of at
least 60 mmHg.
(b) A palpable femoral pulse indicates a systolic blood pressure of at
least 70 mmHg.
A palpable radial pulse indicates a systolic blood pressure of at
least 80 mmHg.