P ulmonary arteriovenous vascular channels larger than typical pulmonary capillaries have been shown to exist in patients with hepatic cirrhosis.’ These enlarged vessels have been demonstrated by quantitative radionuclide techniques.2 It has been difficult or impossible to otherwise demonstrate them during life or in post-mortem studies.3 These apparently dilated vessels are believed to functio...

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) cause substantial morbidity and mortality despite our improved understanding of lung injury, advancements in the application of lung-protective ventilation, and strategies to prevent ventilator-induced lung injury. Severe refractory hypoxemia may develop in a subset of patients with severe ARDS. We review several approaches...

Arterial hypoxemia is a common finding in acute pulmonary embolism, and its severity is generally assumed to be proportional to the extent of pulmonary artery obstruction. We studied blood gases (during room air breathing and 100% oxygen breathing) and hemodynamic data is seven patients with massive pulmonary embolism and circulatory failure. All measurements were made before and 30 minutes aft...

We report a case of ipsilateral reexpansion pulmonary edema occurring after the insertion of a chest tube in a patient with spontaneous pneumothorax. The patient received supplemental oxygen via a non-rebreather face mask to compensate for hypoxemia. 24 hours after the acute event, the patient recovered completely without residual hypoxemia. Reexpansion pulmonary edema after the insertion of a ...

Though uncommon, right-to-left shunt through a patent foramen ovale with normal right-side pressure and with a normal interatrial pressure gradient has been reported. The speculated pathophysiology is attributed to directional blood flow streaming from the vena cava to the left atrium. Hypoxemia secondary to right-to-left shunt with normal pulmonary artery pressure has been extensively document...

The nature of the neurocognitive deficits found in obstructive sleep apnea is still debatable. What is the extent of higher executive versus alertness-based cognitive dysfunction? Are cognitive impairments caused by nighttime hypoxemia or daytime sleepiness? This paper demonstrates the importance of a sound theoretical neurocognitive framework to be able to answer these questions. A strategy to...

Hyperleukocytosis and thrombocytosis may develop in hematological disorders, including acute myelogenous or lymphoblastic leukemia, chronic leukemias in accelerated phase, and polycythemia vera. In such clinical scenarios, patients are at risk for hypoxemia, either true or spurious.1 The causes of true hypoxemia may include pulmonary leukostasis, pneumonia, and pulmonary embolism.1 However, som...

Severe acute chest syndrome afflicts patients with sickle cell disease and can cause hypoxemia refractory to conventional treatments. Obstructive mucus plugging and the development of acute respiratory distress syndrome may underlie the pathophysiology of refractory hypoxemia in acute chest syndrome. Although high-frequency oscillatory ventilation (HFOV) is well established in the treatment of ...