Causes and countermeasures of venous air embolism after injection of contrast media during chest CTA / 中国医学影像技术

ABSTRACT

Objective: To explore the causes and countermeasures of venous air embolism (VAE) after injection of contrast medium during chest CTA. Methods: Totally 4 900 patients who underwent chest CTA were collected consecutively. The incidence, number, size, location, shape and other information of VAE were observed. Results: The incidence of VAE was 4.65% (228/4 900). A total of 318 air emboli were found in 228 patients, in which 285 manifested as air bubbles and 33 as air-liquid planes. There were 155 emboli located in the right atrium, 108 in the main pulmonary artery, 17 in the superior vena cava, 13 in the right ventricle, 13 in the left cephalombrachial vein and 12 in the right cephalombrachial vein, with the average diameter of (2.41±1.45) mm. Small amount of VAE was 90.35% (206/228), medium amount of VAE was 9.65% (22/228), and no large amount of VAE was found. There was no significant difference of the incidence of VAE among different genders, patient types (inpatients/outpatients), examination equipments, contrast agent types nor injection dose (all P>0.05). The incidence of VAE after coronary CTA (193/3 771, 5.12%) was higher than that after thoracic aorta CTA (25/849, 2.94%, P=0.007). Conclusion: The incidence of VAE is low. Most VAEs are asymptomatic after injection of contrast medium during chest CTA examination, but radiologists should still pay attention to VAE and take appropriate measures to avoid or reduce the incidence of VAE.