Case history
Case history #1
A 47-year-old man presents with lethargy, nausea, vomiting, and diarrhoea for 3 days. He has not been able to eat or drink very much. On physical examination, his supine BP is 120/70 and his pulse is 90 bpm. Standing, his BP is 100/50 and his pulse is 120 bpm. Laboratory studies show a serum creatinine that had increased to a peak of 289.8 micromols/L (3.8 mg/dL) from a baseline of 53.4 micromols/L (0.7 mg/dL). His random urine sodium is <10 mmol/L (mEq/L).
Case history #2
A 75-year-old man with a history of hypertension comes in for generalised weakness, lightheadedness, and shortness of breath. He noted bright red stools for the past 2 days. On examination, BP is 90/60 and pulse is 110 bpm. He is pale. A rectal examination reveals bloody stool. Laboratory studies reveal a haemoglobin of 60 g/L (6 g/dL).
Other presentations
Volume depletion may not be obvious initially and its presence is sometimes only confirmed in retrospect, after clinical improvement with volume resuscitation. Confusion alone may be the only symptom in a bed-bound older patient, particularly when accurate postural vital signs cannot be obtained. Postural hypotension and reflex tachycardia are easily missed if not specifically checked, and these signs may be absent even if volume depletion exists.
Use of this content is subject to our disclaimer