Altered Mental Status After Esophagogastroduodenoscopy.

CASE PRESENTATION: A 79-year-old man with medical history of atrial fibrillation and esophageal cancer status post trans-hiatal esophageal resection and chemotherapy presented with altered mental status after outpatient esophagogastroduodenoscopy (EGD). One month before presentation, the patient was seen at another hospital with severe anemia and melena requiring transfusion of multiple units of RBCs. No endoscopy was performed during that admission, but his anticoagulation was held. After follow-up with his oncologist, he was referred for outpatient endoscopy. His esophagogastroduodenoscopy demonstrated an intact esophagogastric anastomosis as well as two gastric ulcers with no stigmata of recent bleeding. The patient was discharged to home in good condition with normal mental status. Several hours later, he developed a deteriorating level of consciousness, prompting presentation to the hospital.

COVID-19 Lung Injury and High-Altitude Pulmonary Edema. A False Equation with Dangerous Implications.

Amid efforts to care for the large number of patients with coronavirus disease (COVID-19), there has been considerable speculation about whether the lung injury seen in these patients is different than acute respiratory distress syndrome from other causes. One idea that has garnered considerable attention, particularly on social media and in free open-access medicine, is the notion that lung injury due to COVID-19 is more similar to high-altitude pulmonary edema (HAPE). Drawing on this concept, it has also been proposed that treatments typically employed in the management of HAPE and other forms of acute altitude illness-pulmonary vasodilators and acetazolamide-should be considered for COVID-19. Despite some similarities in clinical features between the two entities, such as hypoxemia, radiographic opacities, and altered lung compliance, the pathophysiological mechanisms of HAPE and lung injury due to COVID-19 are fundamentally different, and the entities cannot be viewed as equivalent. Although of high utility in the management of HAPE and acute mountain sickness, systemically delivered pulmonary vasodilators and acetazolamide should not be used in the treatment of COVID-19, as they carry the risk of multiple adverse consequences, including worsened ventilation-perfusion matching, impaired carbon dioxide transport, systemic hypotension, and increased work of breathing.

Gas Exchange in the Prone Posture.

The prone posture is known to have numerous effects on gas exchange, both under normal conditions and in patients with ARDS. Clinical studies have consistently demonstrated improvements in oxygenation, and a multi-center randomized trial found that, when implemented within 48 h of moderate-to-severe ARDS, placing subjects in the prone posture decreased mortality. Improvements in gas exchange occur via several mechanisms: alterations in the distribution of alveolar ventilation, redistribution of blood flow, improved matching of local ventilation and perfusion, and reduction in regions of low ventilation/perfusion ratios. Ventilation heterogeneity is reduced in the prone posture due to more uniform alveolar size secondary to a more uniform vertical pleural pressure gradient. The prone posture results in more uniform pulmonary blood flow when compared with the supine posture, due to an anatomical bias for greater blood flow to dorsal lung regions. Because both ventilation and perfusion heterogeneity decrease in the prone posture, gas exchange improves. Other benefits include a more uniform distribution of alveolar stress, relief of left-lower-lobe lung compression by the heart, enhanced secretion clearance, and favorable right-ventricular and systemic hemodynamics.

Tension pneumocephalus: an uncommon cause of altered mental status.

BACKGROUND: Pneumocephalus is a rare cause of altered mental status in patients presenting to the Emergency Department. Occurring as a result of traumatic or iatrogenic violation of the dura, it can cause significant morbidity and mortality if tension physiology develops whereby air continues to accumulate with no mechanism for escape. OBJECTIVE: This case report will review the underlying pathophysiology, clinical presentation, diagnosis, and management of tension pneumocephalus. CASE REPORT: We present the case of an 89-year-old man who presented to the Emergency Department with declining mental status 9h after endoscopic sinus surgery. He was subsequently found to have tension pneumocephalus and underwent emergent burr hole evacuation. Despite resolution of the pneumocephalus, the patient had persistent neurologic deficits related to ischemic infarcts that occurred as a result of the tension physiology and subsequently expired in the hospital. CONCLUSION: This case illustrates the importance of considering tension pneumocephalus on the differential diagnosis for any patient presenting with altered mental status after surgical or diagnostic procedures with potential to violate the dural space.