Sheldon Tobe, MD, FRCPC

Case
The patient is an 80-year-old man, weighing 60 kg. He has a long standing history of hypertension and a more recent history of type 2 diabetes mellitus. He is taking an ACE inhibitor for the treatment of hypertension and microalbuminuria. The patient presents to the local ER suffering from colicky flank pain of 1-day duration. Past medical history includes a remote episode of kidney stones and he says that the pain was similar. He has vomited twice that day and has not taken food or drink since the previous night. He complains that the ER is cold and the nursing notes indicate that he seems peripherally shut down, with hands that are cold and pale. His blood pressure is 110/74 supine and 100/70 standing. His heart rate is 90. A dipstick urinalysis reveals blood and trace protein. Microscopy of the urine reveals hemegranular casts. An IVP is arranged after a KUB suggests the presence of a kidney stone. Ketoprofen, a non-steroidal anti-inflammatory (NSAID) is administered for pain relief. The IVP is non-diagnostic and the patient is admitted for further investigation. The following morning, an urgent call from the lab tells you that the patient's potassium is 6.8 mmol/L, his bicarbonate 14, his urea 15 and his creatinine 200 µmol/L. His ER lab results showed that the urea was 10 mmol/L and the creatinine 120 µmol/L the night before. You are coming on service and find yourself responsible for his care.