A 79-year-old man was brought to the emergency department (ED) by his wife. She complained that the patient had general weakness and was feeling ‘unwell’ for the last two days. He had a history of dementia, diabetes, renal failure, and hypertension. He was on diabetic and antihypertensive medication.
On examination, his vital signs were as follow HR 115/min, BP 135/90 mmHg, RR 17/min, and afebrile with normal oxygen saturation. He was confused and disoriented, but there was no other deficits or localizing signs on neurological exam. He was clinically dehydrated with dry oral mucosa. Lab results showed a serum sodium concentration of 160 mEq/L, with elevated glucose, creatinine, urea, and osmolality. Point of care ultrasound demonstrated a small and almost totally-collapsed inferior vena cava. Upon further history taking, the patient’s wife reported that he had not been drinking much for the last few days, even though he did not complain about thirst.