-IBIS-1.5.0-
tx
cardiovascular system
blood loss
diagnoses

definition and etiology

definition: loss of blood from the circulatory system

etiology: Bleeding may occur overtly, as from a wound where there is much free-flowing blood from the body; or it may be insidious and unnoticeable until symptoms of severe blood loss occur (as into a body cavity). The most obvious common cause of gross bleeding is traumatic injury. Insidious bleeding occurs most often from gastrointestinal causes (peptic ulcers, hemorrhoids, early carcinoma), and although it must be detected through labwork, the effects can be as severe as gross blood loss over time. Women may suffer blood loss either through prolonged heavy menses, or other causes (e.g. ruptured ectopic pregnancy). Death from blood loss occurs from lack of perfusion to tissues necessary to sustain life.

signs and symptoms

signs and symptoms:
• history of traumatic injury and obvious blood loss
• signs and symptoms of anemia: fatigue, weakness, shortness of breath, collapse, dizziness
• if perfusion drops too low, signs of shock may develop within minutes of the blood loss: lethargy, confusion, cold/moist/pale or cyanotic hands and feet, pulse is weak and rapid, tachypnea and hyperventilation at first, and potentially apnea if cerebral perfusion decreases enough to affect the respiratory center

lab findings:
acute:
• shock: low cardiac output with normal or decreased ventricular filling pressure
• anemia: with acute blood loss the RBC, hemoglobin and hematocrit levels are not reliable due to compensatory vasoconstriction and hemodilution; the levels tend to decrease over several days. The anemia is normochromic and normocytic. There are also increased platelets with decreased coagulation time.
• increased BUN with gastrointestinal hemorrhaging
• in occult or menstrual bleeding, there may also be iron deficiency anemia
chronic:
• may be iron deficiency anemia, check occult blood in stool

course and prognosis

Severe blood loss is a medical emergency. Untreated shock syndrome is usually fatal. The prognosis for slow insidious bleeds is better, although it depends upon the cause.

differential diagnosis

• Insidious blood loss needs to be differentiated by lab and physical findings; it must be ruled out quickly if the symptom picture is suspicious.


footnotes