We need you! Join our contributor community and become a WikEM editor through our open and transparent promotion process.
Arterial gas embolism
From WikEM
(Redirected from Air embolus)
Contents
Background
- 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)[1]
- Dialysis related
- Due to negative intrathoracic pressure from spontaneous breathing
- Scuba related
- Results from pulmonary barotrauma (most common) and decompression sickness
Prevention
- Positive pressure mechanical ventilation reduces positive pressure gradient
- Trendelenburg for insertion/removal of IJV and subclav lines
- Reverse Trendelenburg for femoral
Clinical Features
- Asymptomatic
- Mild: dyspnea, cough
- Cardiogenic shock: hypotension, oliguria, altered mental status, chest pain
- Dialysis related
- Acute dyspnea, chest tightness, LOC, cardiac arrest
- Scuba related
- Symptoms develop during ascent or immediately upon surfacing
- Causes variety of stroke syndromes depending on part of brain affected
- Immediate death, loss of consciousness, seizure, blindness, hemiplegia
Differential Diagnosis
Dialysis Complications
- Dialysis-associated hypotension
- Dialysis disequilibrium syndrome
- Air embolism
- Missed dialysis (pulmonary edema)
Scuba Diving Emergencies
- Barotrauma of descent
- Barotrauma of ascent
- Pulmonary barotrauma (pulmonary overpressurization syndrome)
- Decompression sickness (DCS)
- Arterial gas embolism
- At depth injuries
- Oxygen toxicity
- Nitrogen narcosis
- Hypothermia
- Contaminated gas mixture (e.g. CO toxicity)
Evaluation
- Low ETCO2 in significant venous air embolism
- TEE: most sensitive, invasive not available in emergencies
- Doppler US: noninvasive; air in chamber = high pitch sound
Management[2][3]
- Central line aspiration of air from right heart
- 100% O2 non-rebreather
- Hemodynamic support with positive inotropes
- Rapid CPR in large air embolus
- Positioning
- 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
Dialysis Related
- Prevent any further air entry
- Immediately cover puncture site with saline soaked gauze
Scuba Related
- IVF (increases tissue perfusion)
- Rapid recompression
See Also
External Links
References
- ↑ Vascular Access. In: Marino, P. The ICU Book. 4th, North American Edition. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013
- ↑ *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.
