Arterial gas embolism
- Also known as "air embolism"
- May be fatal when air entry reaches 200-300 mL (pressure gradient of 5 mmHg across 14 ga catheter entrains air at 100 mL/sec)
- Dialysis related
- Due to negative intrathoracic pressure from spontaneous breathing
- Diving related
- Results from pulmonary barotrauma (most common) and decompression sickness, most commonly in last 10m of ascent.
- Classically presents as LOC within 2 minutes of surfacing, can lead to stroke-like symptoms.
- Positive pressure mechanical ventilation reduces positive pressure gradient
- Trendelenburg for insertion/removal of IJV and subclav lines
- Reverse Trendelenburg for femoral
- Slow and controlled ascent when diving, with special precaution to exhale during ascent in the last 10m so the lungs do not over-pressurize.
- Mild: dyspnea, cough
- Cardiogenic shock: hypotension, oliguria, altered mental status, chest pain
- Dialysis related
- Acute dyspnea, chest tightness, LOC, cardiac arrest, arrhythmia
- Scuba related
- Barotrauma of descent
- Barotrauma of ascent
- At depth injuries
- Low ETCO2 in significant venous air embolism
- TEE: most sensitive, invasive not available in emergencies
- Doppler US: noninvasive; air in chamber = high pitch sound
- Central line aspiration of air from right heart
- 100% O2 non-rebreather
- Regardless of SaO2 (to reduce embolism size)
- Hemodynamic support with positive inotropes
- CPR in large air embolus
- Durant's maneuver - left lateral decubitus and Trendelenburg
- Traps air in apex of RV, relieves obstruction of pulmonary outflow tract
- May require open surgical or angiography for recovery of residual intracardiac or intrapulmonary air
- Prevent any further air entry
- Immediately cover puncture site with saline soaked gauze
- IVF (increases tissue perfusion)
- Rapid recompression, hyperbaric oxygen therapy
- Likely admission
- Vascular Access. In: Marino, P. The ICU Book. 4th, North American Edition. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013
- Diving Medicine, Karen B. Van Hoesen and Michael A. Lang, Auerbach's Wilderness Medicine, Chapter 71, 1583-1618.e6
- Shaikh N., Ummunisa F. Acute management of vascular air embolism. J Emerg Trauma Shock. 2009 Sep-Dec; 2(3): 180–185.
- Gordy S and Rowell S. Vascular air embolism. Int J Crit Illn Inj Sci. 2013 Jan-Mar; 3(1): 73–76.