What is the diagnosis and management of an air embolism (AE)?

From the Guidelines

Air embolism diagnosis and management should prioritize immediate prevention of further air entry, reduction of existing emboli, and hemodynamic support, with the patient placed in the left lateral decubitus position and administered high-flow oxygen, as recommended by the most recent guidelines 1. The diagnosis of air embolism relies on recognizing risk factors such as central line placement, surgery, and trauma, as well as symptoms including sudden hypotension, chest pain, altered mental status, and respiratory distress. Confirmation may involve transthoracic echocardiography, CT scans, or transesophageal echocardiography. Key management strategies include:

• Placing the patient in the left lateral decubitus position with Trendelenburg (head down) to trap air in the right atrium away from the pulmonary outflow tract
• Administering high-flow oxygen (100% if possible) to create a diffusion gradient that helps eliminate nitrogen from the bubbles
• Immediately clamping the catheter and aspirating any remaining air for central line-associated air embolism
• Providing hemodynamic support with IV fluids (normal saline bolus of 500-1000mL) and vasopressors (norepinephrine 0.1-0.5 mcg/kg/min) as needed for hypotension
• Considering hyperbaric oxygen therapy at 2.5-3.0 atmospheres for 2-4 hours within 6 hours if available, especially for cerebral air embolism, as it reduces bubble size and improves oxygenation 1. Prevention remains crucial through careful central line insertion techniques, proper patient positioning during surgery, and meticulous attention during procedures with risk of air entry into the circulation. The most recent and highest quality study 1 provides the best guidance for managing air embolism, emphasizing the importance of prompt recognition and intervention to minimize morbidity and mortality.

From the Research

Diagnosis of Air Embolus

• Air embolism is a rare but potentially fatal complication of surgical procedures, with 94% of cases occurring in-hospital 2
• Clinical signs and symptoms are related to the location of the air embolus, with 36 cases affecting the right heart/pulmonary artery, 21 affecting the cerebrum, and 10 attributed to patent foramen ovale (PFO) 2
• Venous air emboli may occur during pressurized venous infusions or catheter manipulation, while arterial air emboli may occur as a complication from lung biopsy, arterial catheterization, or cardiopulmonary bypass 3

Management of Air Embolus

• Immediate management includes placing the patient on high-flow oxygen and in the right lateral decubitus position for arterial air emboli, or the left lateral decubitus and/or Trendelenburg position for venous air emboli 3
• Hyperbaric oxygen therapy is the definitive treatment, which may decrease the size of air emboli by facilitating gas reabsorption, while also improving tissue oxygenation and reducing ischemic reperfusion injury 4, 3
• Aspiration of the air and hyperbaric oxygen therapy were used in 7.5% and 21% of patients, respectively, with 63% having no sequelae 2

Prevention of Air Embolus

• Air embolism can be preventable with appropriate precautions and techniques, particularly during the use of endovascular techniques 5
• Central venous catheters and arterial catheters are at high risk for air embolism, and a heightened awareness of this complication is warranted 5
• High clinical suspicion and early treatment are critical for survival, with mortality rates ranging from 13.5% to 53.8% depending on the presence of immediate cardiac arrest 2