Hypokalemia increases ammonia production in the proximal tubules, which can exacerbate hyperammonemia in patients with hepatic encephalopathy. However, there are few reports of hyperammonemia due to hypokalemia in the absence of hepatic failure or a portosystemic shunt. Herein, we present the case of a 77-year-old patient with hypokalemia, hyperammonemia and impaired consciousness. The cause of hypokalemia was considered to be pseudohyperaldosteronism due to glycyrrhizin contained in shakuyakukanzoto. In this case, only fatty liver was present without cirrhosis, liver failure, or portosystemic shunt. No other causes for loss of consciousness were determined other than hyperammonemia. The impaired consciousness and hyperammonemia were improved with correction of the hypokalemia. The causes of hyperammonemia were considered to be the following: (1) the increased production of ammonia in the proximal tubule due to hypokalemia; (2) the increased transfer of ammonia into the blood due to alkalosis; (3) the decreased capacity for urea synthesis due to chronic hypokalemia; and (4) the decreased ammonia metabolism due to liver dysfunction associated with fatty liver. Therefore, hyperammonemia should be considered as a differential diagnosis in patients with hypokalemia and impaired consciousness regardless of the degree of liver dysfunction.

Prompt tracheal stenting is a life-saving measure for patients with advanced airway stenosis. A 70s-year-old man was brought to the emergency room because of severe airway stenosis due to compression of the trachea by a posterior mediastinal tumor. The emergency physician requested the intensivist to intubate the patient. However, computed tomography of the site of stenosis revealed that safe intubation would not be possible for the patient. The respiratory physician, cardiovascular surgeon, and clinical engineer decided to immediately perform veno venous extracorporeal membrane oxygenation (ECMO) to remove blood from the femoral vein and deliver it to the internal jugular vein. After the stent insertion was prepared, the patient was transferred to the operating room for tracheobronchial stent insertion. Intraoperatively, the tracheal stent was safely placed under general anesthesia and muscle relaxant administration without tracheal intubation by maintaining oxygenation while adjusting the ECMO flow rate. Postoperatively, endotracheal intubation was performed to confirm that adequate ventilation was feasible, and the patient was weaned off ECMO. The following morning, the patient was weaned off the ventilator and could be extubated. Prompt decision-making through multidisciplinary collaboration is important.

A patient who required mechanical ventilation because of Guillain–Barré syndrome that developed abroad was transferred to our hospital via a medical jet. On admission, the patient received continuous intravenous (IV) infusions of midazolam (0.9 mg/kg/hr), dexmedetomidine (1.9 μg/kg/hr), propofol (1.3 mg/kg/hr), and remifentanil (0.27 μg/kg/min). The patient was also given an enteral administration of pregabalin (300 mg/day), quetiapine (300 mg/day), and trazodone (150 mg/day). After discontinuing the administration of midazolam, dexmedetomidine, and remifentanil, the patient developed severe body movements and tachypnea, which prompted the admission of the patient to the ICU. After IV administration of ketamine (50 mg), continuous ketamine administrations (0.53 mg/kg/hr) were initiated, which resulted in adequate sedation. Suspecting withdrawal syndrome, we then reinitiated infusions of midazolam, dexmedetomidine, and fentanyl. The dose for each drug was then tapered before being discontinued. The patient was discharged to the general ward after 15 days in the ICU and was then transferred to a rehabilitation center after 47 days of hospitalization.