CHEST Guidelines-An-Unusual-Cause-of-Severe-Hypoxemia-and-Acute-Res

An-Unusual-Cause-of-Severe-Hypoxemia-and-Acute-Res

Pdf Summary

In a detailed case study published in CHEST in 2020, physicians delved into an unusual cause of severe hypoxemia and acute respiratory distress syndrome (ARDS) resulting from acute mercury inhalation poisoning. The patient, a 50-year-old man with a history of coronary artery disease and substance abuse, initially presented with dyspnea and chest pain. Diagnostic tests revealed diffuse bilateral opacities consistent with pulmonary edema, without focal consolidation. After utilizing mercury to purify gold at home, he was admitted to the hospital and initially treated with supplemental oxygen and steroids, leading to temporary improvement. However, he returned to the emergency room post-discharge with exacerbated symptoms requiring intubation and mechanical ventilation due to his progressive hypoxemia. His blood mercury level was alarmingly high at 380 ng/mL (normal being 0-9 ng/mL), confirmed by heightened urinary mercury levels. <br /><br />The patient’s severe condition necessitated prompt intervention through chelation therapy with succimer and systemic steroids. Despite initiating chelation and implementing supportive critical care measures, including prone positioning and neuromuscular blockade, his condition required transfer to a specialized ARDS center. At the referral center, extended chelation therapy duration was adapted based on his mercury levels, which were closely monitored. His treatment included protective lung ventilation strategies and a fluid-restrictive protocol, transitioning to spontaneous ventilation after sedation was reduced. Following an extended ICU stay and rehabilitation, he was successfully weaned from mechanical ventilation.<br /><br />This case underscores the critical importance of history-taking to identify potential environmental exposures, like mercury vapor, which can cause life-threatening respiratory complications. It emphasizes the urgency of initiating chelation therapy in confirmed mercury vapor inhalation cases to potentially mitigate severe outcomes, although definitive data on the clinical efficacy of chelation in lung injury from mercury inhalation remains limited.

Keywords

mercury inhalation poisoning

acute respiratory distress syndrome

hypoxemia

chelation therapy

pulmonary edema

mechanical ventilation

protective lung ventilation

environmental exposures

critical care

substance abuse