Pediatric emergency medicine trisk 0686 0686
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needs to be differentiated from hemoptysis (bleeding from the airways). Patients with
hemoptysis often have chronic lung disease, congestive heart failure, or a severe cough.
Severity of Bleeding
Estimation of blood loss (a few drops, a spoonful, a cupful, or more) should be
ascertained initially, although this can be difficult and inaccurate. Hemoglobin and
hematocrit are also unreliable estimates of acute blood loss because of the time required
for hemodilution to occur after an acute hemorrhage. The estimated volume of blood
loss should be correlated with the patient’s clinical status. In pediatrics, a patient may
lose 15% of their circulating blood volume prior to changes in the vital signs. The
presence of resting tachycardia, pallor, prolonged capillary refill time, and metabolic
acidosis points to significant enteral blood loss. Hypotension is a late finding in young
children, typically after greater than 30% of blood volume has been lost, and should be
treated as hemorrhagic shock demanding immediate resuscitative measures (intravenous
fluids and blood transfusion).
Children with only a few drops or flecks of blood in the vomit or stool should not be
considered “GI bleeders” if their history and physical examinations are otherwise
unremarkable. Caution must be taken, however, as small amounts of blood (whether in
emesis or passed per rectum) may be the harbinger of more extensive enteral bleeding.
Establishing the Level of Bleeding
There are two general categories of GI bleeding: upper and lower. Upper GI bleeding
refers to bleeding proximal to the ligament of Treitz (distal duodenum). Twenty percent
of GI bleeds in pediatrics are from the upper GI tract. Lower GI bleeding is distal to the
ligament of Treitz. In most cases, the clinical findings along with nasogastric lavage will
delineate the cause of bleeding within the GI tract. Hematemesis, defined as the
vomiting of blood, can range from fresh and bright red to old and dark with the
appearance of “coffee grounds” (due to the effect of gastric acidity). Hematochezia, the
passage of bright red blood per rectum, suggests lower GI bleeding or upper GI bleeding
with a very rapid enteral transit time (such as in infants). Melena, the passage of stool
that is shiny, black, and sticky, reflects bleeding from either the upper GI tract or the
proximal large bowel. In general, the darker the blood in the stool, the higher it
originates in the GI tract (or, alternatively, the longer it has resided in the GI tract).
“Currant jelly” stools indicate vascular congestion and hyperemia of the colon with
passage of blood mixed with mucus, as seen with intussusception. Maroon-colored
stools generally occur with a voluminous bleed anywhere proximal to the rectosigmoid
area, such as seen with a Meckel diverticulum.
Patients with a significant bleeding episode should have a nasogastric tube placed for
a diagnostic saline lavage ( Fig. 33.1 ). In patients with hematemesis or melena, a
nasogastric aspirate yielding blood confirms an upper source of GI bleeding, whereas a
negative result almost always excludes an active upper GI bleed. Occasionally, a
postpyloric upper GI lesion, such as a duodenal ulcer, bleeds massively without reflux
