**2. Fat embolism**

Fat Embolism (FE) is by far the most frequent NTPE observed outside the clinical setting of Obstetrics-Gynecology. The term FE refers to the presence of fat globules within the

Non-Thrombotic Pulmonary Embolism 77

Trauma, orthopedic procedures and soft tissue injuries including severe burns are by far the most common causes of FE and FES. FES is more likely to develop after pelvic or lower extremity fractures; it is seldom observed in patients with isolated upper extremity

**Characteristics Comments** 

• Physically most active age group –

• Children <10 yrs old: lower fat and olein content of the bone marrow (hence, less likely to develop FES)

• Elderly : low impact fractures,

embolization.

common site

1972).

Table 1. Traumatic Fat Embolism - Factors predisposing to FES among Trauma patients

Femur (excluding neck) is the single most

More marrow is available for embolization

Higher pressure is more likely to develop in

2007; ten Duis et al., 1988; Thomas & Ayyar,

closed than open (Dedhia & Mushambi,

mostly single fracture, mainly involving the neck of the femur thus less intramedullary pressure and less marrow is available for

higher risk of trauma

**4. Risk factors** 

Age: 10-40 years – peak incidence

**Location of fracture(s) in order of** 

• Upper extremity • Rib & vertebrae

**Number of fracture(s)**

Multiple > single

**Type of fracture** Closed > open

• Lower extremity and/or pelvic

fractures.

Sex : M > F

**incidence:**

Fig. 1. Different sub-types of NTPE (Reproduced with permission – Jorens et al, ERJ 2009)

peripheral and pulmonary circulation. It can range from being asymptomatic to life threatening respiratory failure with or without neurological and other systemic manifestations often described as Fat Embolism Syndrome (FES).
