Critical Care Medicine-Pulmonary Disorders>>>>>Thromboembolic Disease and Hemoptysis
Question 7#

Which of the following statements regarding the signs and symptoms of venous air embolism (VAE) is INCORRECT?

A. Bradyarrhythmias are the most common arrhythmias that occur with VAE
B. Substernal chest pain, right heart failure, and cardiovascular collapse commonly occur with entrained volumes over 2 mL/kg
C. Increased end tidal nitrogen and decreased end tidal carbon dioxide can be seen with less than 0.5 mL/kg of air entrainment
D. Paradoxical air embolism could occur across the lung vascular bed in patients with VAE

Correct Answer is A

Comment:

Correct Answer: A

The clinical effects of VAE depend on the volume and rate of entrainment of air. Spontaneous respiration with negative intrathoracic pressure could facilitate further entrainment of air. Venous air embolism can present with arrhythmias. Tachyarrhythmias are common but bradyarrhythmias can occur, as well. Associated substernal chest pain could be a presenting symptom. Right heart failure and cardiovascular collapse are more often seen with large volumes of entrainment—around 2 mL/kg. Changes in levels of monitored gases like nitrogen and carbon dioxide can occur with smaller volumes of air entrainment. Fundoscopy is typically normal. Rarely, air bubbles can be seen within the retinal vessels. Paradoxical embolism could happen either through a patent foramen ovale or by overwhelming the capacity of the lungs to filter the air emboli.

References:

1. Mirski M, Lele A, Fitzsimmons L, Toung T. Diagnosis and treatment of vascular air embolism. Anesthesiology. 2007;106:164-177.
2. Muth C, Shank E. Gas embolism. N Engl J Med. 2000;342:476-482.