A 65-year-old man is evaluated in the hospital for acute-onset shortness of breath. The patient was originally admitted 5 days ago for peritonitis due to a perforated peptic ulcer, for which he underwent surgical repair. A large-bore, right internal jugular venous catheter was placed during the operation. Today, he was out of bed, sitting in a chair, and comfortable on room air. The internal jugular catheter was removed. Minutes after catheter removal, the patient develops acute-onset shortness of breath and cough. On examination, he appears in respiratory distress. Blood pressure is 110/60 mm Hg, pulse is 110/min, and respirations are 25/min. Oxygen saturation is 85% on room air. The jugular veins are distended. Breath sounds are normal and equal on both sides. In addition to high-flow oxygen supplementation, the patient should be immediately placed in which of the following positions?

Question

A 65-year-old man is evaluated in the hospital for acute-onset shortness of breath.  The patient was originally admitted 5 days ago for peritonitis due to a perforated peptic ulcer, for which he underwent surgical repair.  A large-bore, right internal jugular venous catheter was placed during the operation.  Today, he was out of bed, sitting in a chair, and comfortable on room air.  The internal jugular catheter was removed.  Minutes after catheter removal, the patient develops acute-onset shortness of breath and cough.  On examination, he appears in respiratory distress.  Blood pressure is 110/60 mm Hg, pulse is 110/min, and respirations are 25/min.  Oxygen saturation is 85% on room air.  The jugular veins are distended.  Breath sounds are normal and equal on both sides.  In addition to high-flow oxygen supplementation, the patient should be immediately placed in which of the following positions?

Quizplus · Accepted Answer

11ec25c8_d938_5fd2_bc81_ffdd767497fd_MD0003_00 This patient with sudden-onset respiratory distress following removal of a central venous catheter has most likely developed a venous air embolism (VAE); the venous circulation is susceptible to air embolism due to relatively low intravascular hydrostatic pressure. VAE travels to the right ventricle, where it can obstruct the right ventricular outflow tract (RVOT), or it can travel farther to the pulmonary arterioles, where it can obstruct pulmonary capillary blood flow, leading to ventilation-perfusion mismatch and hypoxemia. Obstructive shock and cardiac arrest can result. Patients with suspected VAE should immediately be placed in the left lateral decubitus or left lateral Trendelenburg (left lateral decubitus with head down) position, which traps the VAE on the lateral wall of the right ventricle, preventing RVOT obstruction and further embolization of air into the pulmonary circulation. High-flow oxygen (or, in severe cases, hyperbaric oxygen) is also important as it shrinks the air embolus by encouraging the absorption of nitrogen gas (the main component of atmospheric air) into the blood. lateral wall (Choice B) Prone positioning reduces atelectasis in the posterior lung (where most of the lung mass is located) and is sometimes used to improve oxygenation in patients with severe acute respiratory distress syndrome and persistent hypoxemia despite optimal mechanical ventilation settings. (Choice C) Right lateral decubitus positioning is likely to encourage movement of air into the RVOT and may worsen the clinical manifestations of VAE. (Choice D) Semirecumbent positioning may lower the risk of ventilator-acquired pneumonia in intubated patients on mechanical ventilation. (Choice E) Patients with suspected arterial (rather than venous) air embolism should be placed in supine positioning, as it helps prevent the embolism from traveling to the brain and causing a stroke. Educational objective: Venous air embolism (VAE) is suggested by sudden-onset respiratory distress following removal of a central venous catheter. Patients with suspected VAE should immediately be placed in the left lateral decubitus position to trap air on the lateral right ventricular wall and help prevent right ventricular outflow tract obstruction and embolization of air into the pulmonary circulation. High-flow oxygen is also important to encourage absorption of the air embolus. References: Venous air embolism: clinical and experimental considerations. (http://www.ncbi.nlm.nih.gov/pubmed/1643897)

A 65-Year-Old Man Is Evaluated in the Hospital for Acute-Onset