A patient has a pulmonary embolism and is started on oxygen.
The student nurse asks, "What are the risk factors for a pulmonary embolism?" Which of the following is not a correct answer?

Choice A rationale

A loud, brassy cough in a burn patient rescued from a fire is a critical sign of upper airway edema, often caused by inhalation of hot gases or toxins. This swelling can rapidly lead to complete airway obstruction. Antitussive medications suppress coughing and would mask this vital clinical sign, delaying the necessary and immediate intervention of securing the airway.

Choice B rationale

Providing ice chips or sips of water may be considered for a sore throat, but in the context of a potential inhalation injury, this action is contraindicated. Swelling of the laryngeal and pharyngeal tissues can progress rapidly, and there is a high risk of aspiration if the patient's swallowing reflex is compromised or the airway becomes obstructed.

Choice C rationale

Humidified air can help soothe irritated mucous membranes, but it is not the first action in a patient with a rapidly deteriorating airway. The loud, brassy cough signifies significant laryngeal edema, which can progress to complete obstruction. The immediate priority is to assess, stabilize, and protect the airway with supplemental oxygen and continuous monitoring before it closes.

Choice D rationale

A loud, brassy cough is a hallmark sign of upper airway edema, a serious complication of inhalation injury. The swelling can quickly lead to airway obstruction. Applying oxygen and continuous pulse oximetry is the first action to ensure adequate oxygenation and monitor for signs of impending respiratory failure, while simultaneously preparing for definitive airway management.

Choice A rationale

Anorexia nervosa is a psychiatric eating disorder characterized by a low body mass index due to a distorted body image and an intense fear of gaining weight. While it can lead to various health complications, it is not a direct or established risk factor for the formation of a pulmonary embolism. The primary risk factors are related to Virchow's triad: venous stasis, hypercoagulability, and endothelial injury. Anorexia does not directly cause any of these conditions.

Choice B rationale

Immobility or prolonged travel, such as sitting for more than four hours, significantly increases the risk of deep vein thrombosis (DVT), a precursor to pulmonary embolism. Prolonged inactivity leads to venous stasis, where blood pools in the lower extremities. This sluggish blood flow promotes the aggregation of platelets and clotting factors, increasing the likelihood of thrombus formation in the deep veins of the legs.

Choice C rationale

Pregnancy is a significant risk factor for pulmonary embolism due to several physiological changes. The gravid uterus compresses the inferior vena cava, causing venous stasis in the lower extremities. Additionally, pregnancy induces a hypercoagulable state to prevent excessive bleeding during childbirth. The combination of venous stasis and hypercoagulability significantly elevates the risk of DVT and subsequent PE.

Choice D rationale

Central venous catheters are a well-established risk factor for both DVT and pulmonary embolism. The presence of a foreign body in a large vein, such as the subclavian or jugular vein, causes localized endothelial injury. This damage to the vascular lining triggers the coagulation cascade, promoting the formation of a thrombus directly on or around the catheter tip. The thrombus can then embolize to the lungs.