**Question:** Clinical feature of fat embolism includes all except:

A. Confusion or altered mental status
B. Hypotension
C. Respiratory distress
D. Hypoxemia

**Correct Answer:** B. Hypotension

**Core Concept:** Fat embolism is a rare but potentially life-threatening complication following long bone fractures or trauma involving bone marrow. It occurs when fat globules, which are typically filtered out by the lungs, enter the circulation and lodge in the pulmonary capillaries, leading to respiratory and neurological symptoms.

**Why the Correct Answer is Right:** Hypotension is not a typical clinical feature of fat embolism. Fat emboli can cause respiratory distress, confusion, and hypoxemia due to the obstruction of pulmonary capillaries and reduced oxygenation. Although hypotension can be a symptom in some cases, it is not a universally present feature in fat embolism.

**Why Each Wrong Option is Incorrect:**

A. Confusion or altered mental status: Fat emboli can lead to neurological complications due to the obstruction of cerebral capillaries, causing neurological symptoms like confusion or altered mental status. This is a correct feature of fat embolism.

B. Hypotension: As mentioned above, hypotension can be a feature of fat embolism, but it is not a universal symptom.

C. Respiratory distress: Fat emboli can obstruct pulmonary capillaries, leading to reduced oxygenation and respiratory distress. This is a correct feature of fat embolism.

D. Hypoxemia: Hypoxemia occurs due to the obstruction of pulmonary capillaries, leading to reduced oxygenation. This is a correct feature of fat embolism.

**Clinical Pearl:** Fat embolism is a clinical syndrome that should be suspected in patients with acute bone or joint trauma, particularly in those with respiratory distress, neurological symptoms, and hypoxemia. Prompt recognition and management are crucial to prevent complications and improve outcomes.