Melena suggests which of the following?

AIIMS Bhopal NO - 2018 (Shift-1st)

Medical & Surgical Nursing

Easy

Appeared in: AIIMS Bhopal NO - 2018 (Shift-1st)

Explanation

Melena is defined as the passage of black, tarry, and foul-smelling stools.
This condition specifically indicates bleeding originating from the upper gastrointestinal (GI) tract, which includes the esophagus, stomach, or duodenum.
The characteristic black color is due to the chemical alteration of hemoglobin by digestive enzymes and stomach acid as the blood passes through the intestines.
Common causes of upper GI bleeding leading to melena include peptic ulcers, erosive gastritis, and esophageal varices.

Option B: A head injury does not directly cause gastrointestinal bleeding. While severe physiological stress from a major head injury can sometimes lead to stress ulcers (Cushing's ulcer) that may bleed, the primary injury is in the head, not the bowel.
Option C: Injury or bleeding in the lower bowel (colon, rectum) results in hematochezia, which is the passage of fresh, bright red blood. The blood does not remain in the GI tract long enough to be digested and turn black.
Option D: A miscarriage involves vaginal bleeding originating from the uterus. It is completely unrelated to the gastrointestinal tract and does not cause changes in stool color.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Differentiation between upper and lower gastrointestinal bleeding based on stool appearance as background academic context rather than a clinical decision trigger.
Identifying melena is a critical nursing assessment. It signals a significant upper GI bleed that requires immediate notification of the healthcare provider and close monitoring of the patient.
A patient with melena is at risk for hypovolemic shock. The nurse must monitor vital signs frequently (tachycardia, hypotension), assess for pallor and dizziness, and check hemoglobin/hematocrit levels.
Nursing interventions include maintaining IV access, preparing for potential blood transfusions, and assisting with diagnostic procedures like an upper endoscopy.

How to Approach the Question

First, identify the key term in the question stem: 'Melena'.
Recall the clinical definition of melena, which is black, tarry stool resulting from digested blood.
Connect the appearance of the stool to the anatomical location of the bleeding. The black color indicates the blood has been present in the GI tract long enough to be acted upon by digestive enzymes, pointing to an 'upper' source.
Evaluate the given options based on this physiological principle. 'Injury to the upper bowel' directly aligns with the cause of melena.
Systematically eliminate the other options. 'Lower bowel' injury causes fresh, red blood (hematochezia). 'Head injury' and 'Miscarriage' are unrelated to primary GI bleeding.

Concept Tested & Keywords

Concept Tested: Differentiation between upper and lower gastrointestinal bleeding based on stool appearance.
Stem keywords: Melena
Lead-in keywords: suggests

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