Using point-of-care lung ultrasound to detect post-thoracentesis complications: the hydro-point case report

Introduction: Pneumothorax is a common complication of medical procedures that often occurs after thoracentesis despite the use of ultrasound guidance. Point-of-care lung ultrasound (POCUS) is a rapid and efficient diagnostic tool for pneumothorax. Case presentation: A 78-year-old man with severe ischemic cardiomyopathy was admitted with acute pulmonary edema and hypotension. He was managed with diuretics and inotropes. Due to severe left pleural effusion, a diagnostic left thoracentesis was performed, and the pleural fluid analysis revealed it was transudative. The follow-up chest X-ray revealed no pneumothorax. POCUS showed an interposition between the aerated pleural space, presenting as A lines (A pattern), and the fluid interface in the pleural space, which produces an anechoic sonographic pattern, resulting in the classical appearance of ultrasonic hydropneumothorax. Discussion: Although the ultrasonic lung point for diagnosing pneumothorax has been well described and documented in the literature, particularly after procedures in the ICU, few studies have detailed the ultrasonography patterns observed in cases of hydropneumothorax following pleural effusion tapping. Postprocedural hydropneumothorax was characterized by the ultrasonographic interposition of air and fluid and was referred to as the “air‒fluid mirror.” Others suggested that the “hydro-point” is more appropriate. Conclusion: Pneumothorax is a common complication of medical procedures that often occurs after thoracentesis despite the use of ultrasound guidance. POCUS is a rapid and efficient diagnostic tool for post-thoracocentesis hydropneumothorax, based on distinct sonographic signs, including the “Hydro-point.”