A nurse is caring for a client 24 hours after open reduction internal fixation (ORIF) of a femur fracture. Which nursing intervention should be the priority to prevent the most serious postoperative complication?

Monitoring for fat embolism signs is the priority as it is a life-threatening complication requiring immediate intervention. Other interventions prevent less urgent complications.

Priority Intervention Rationale

The priority nursing intervention is to monitor for signs of fat embolism syndrome (FES). In the 24 to 72 hours following a long bone fracture repair, such as an open reduction internal fixation (ORIF) of the femur, the patient is at the highest risk for developing FES. This condition, while rare, is a life-threatening emergency that requires immediate recognition and supportive care. The classic triad of clinical manifestations includes respiratory distress, neurological abnormalities like altered mental status, and a petechial rash [1,2]. Because respiratory failure and cerebral involvement can progress rapidly, vigilant assessment for these signs takes precedence over interventions aimed at preventing less immediately lethal complications like deep vein thrombosis or infection.

Pathophysiology and Clinical Presentation

FES occurs when fat globules from the bone marrow enter the venous system and obstruct the microvasculature, primarily in the lungs and brain. The exact mechanism is believed to be both mechanical obstruction and a biochemical inflammatory cascade. The case reports highlight that the presentation can be atypical, making continuous monitoring essential. For instance, a patient may develop sudden hypoxemia, tachypnea, tachycardia, and fever shortly after surgery, which can mimic a pulmonary thromboembolism [1,2]. A key diagnostic clue is that a CT pulmonary angiogram will be negative for a thrombus but may show diffuse infiltrates, helping to differentiate FES from a pulmonary embolism [1,2]. Critically, the absence of a petechial rash or early neurological symptoms does not rule out the syndrome, as demonstrated by a patient who presented with only respiratory distress and fever ^[2]. This underscores why a high index of suspicion and systematic assessment are paramount.

Analysis of Other Options

While all the listed interventions are important components of postoperative care for a femur fracture, they do not address the most immediate and serious threat to life.

- Option 1: Encouraging ankle pumps and calf exercises is a core intervention to prevent venous thromboembolism (VTE), such as deep vein thrombosis (DVT). Although a DVT can lead to a pulmonary embolism, which is also a serious complication, its onset is generally less abrupt and catastrophic than a fulminant fat embolism. The prophylactic nature of this intervention makes it a lower priority than the active surveillance required for FES.
- Option 3: Assisting with a continuous passive motion (CPM) machine is beneficial for maintaining joint mobility and preventing stiffness after a total knee replacement, not a femur ORIF. Even if applied in a different context, this intervention focuses on long-term functional recovery, not on preventing an immediate, life-threatening complication.
- Option 4: Assessing the surgical site and maintaining a sterile dressing prevents surgical site infection. Infection is a significant concern that can lead to osteomyelitis or sepsis, but its development typically occurs over days, not within the first 24 hours. The acute, rapidly progressive nature of FES makes its early detection a more time-sensitive priority.

The evidence confirms that the period of greatest risk for FES is the early postoperative phase, with symptoms manifesting as early as the day after surgery [1,2]. Therefore, the nurse's immediate focus must be on systematic respiratory and neurological assessments to detect this syndrome at its earliest, most treatable stage.