ABSTRACT
Caput medusae, from Latin = head of Medusa; Medusa was a mythological creature who had snakes for hair and would turn those who looked at her into stone.
1. L – Pre-renal acute renal failure secondary to hypovolaemia Acute renal failure can be defined as the deterioration of renal function over hours or days. By far the most common cause of acute renal failure is hypoperfusion of the kidney, referred to as pre-renal acute renal failure. This is usually seen with hypovolaemia secondary to conditions such as acute blood loss, vomiting, diarrhoea and burns. It may also occur in normovolaemic patients with sepsis, cardiac failure or renal artery stenosis. Investigation demonstrates high serum urea, creatinine and potassium concentrations, and a poor urine output. Prerenal acute renal failure is treated by correcting the underlying condition and restoring the patient’s circulating volume with intravenous fluids. If the kidneys
condition is known as acute tubular necrosis (ATN) and results in failure of active sodium reabsorption and failure to concentrate the urine. The urine produced in ATN typically has a high sodium concentration, a low osmolarity, a low urine: serum urea ratio and a low urine:plasma osmolarity ratio. ATN usually resolves if the underlying cause is corrected and appropriate fluid therapy is delivered, although recovery may take weeks. During recovery, there is an oliguric phase (when both glomerular filtration and tubular function are compromised), followed by a diuretic phase (when glomerular filtration recovers before tubular function is regained).
