LESSON 2
Section I. GENERAL
2-1.
HYPOVOLEMIC SHOCK
Blood supplies the brain and other body parts with the oxygen and nutrients
they need to live and function. A sudden decrease in the amount of blood in the
circulatory system, such as that caused by severe bleeding, endangers these tissues.
A sudden decrease in blood volume can also produce hypovolemic (low volume)
shock. An average adult has about six quarts (around 5000 to 6000 milliliters) of blood
in his body.
a. Blood products can not be replaced on the front line of the battlefield, so it
must be stopped at all costs. The old school of thought of treating with direct pressure
and then elevation and working your way to a tourniquet as a last resort is antiquated.
Modern medical research has proven that on the battlefield lives will be saved with the
aggressive use of tourniquets and then attempting to reduce these to pressure
b. Figure 2-1 shows the effects of blood loss on the body. This guide can help
you determine the amount of loss the patient has already suffered. Once the patient
has reached stages lll and lV, it is often too late. This helps to demonstrate the
importance of early and aggressive control of hemorrhage on the battlefield.
Class
Blood Loss
Clinical Signs
I
Up to 750 ml
Slight increase in heart rate; no
(15 percent)
change in blood pres sure or
respiration s
II
750 to 1500 ml
Increased heart rate and
(15 to 30 percent)
respirations; increased diastolic
blood pressure; anxiety, fright or
hostility
III
1500 to 2000 ml
Increased heart rate and
respirations; fall in systolic blood
(30 to 40 percent)
pressure; signific ant AMS
IV
Over 2000 ml
Severe tachycardia; severe
(over 40 percent)
lowering of blood pressure; cold,
pale skin; severe AMS
NOTE: Altered mental status (AMS).
Figure 2-1. Effects of blood loss.
MD0554
2-2