(Blood urea &/or renal function) or (urea [& serum level]) or (urea and electrolytes)
(blood urea &/or renal function) or (urea [& serum level]) or (urea and electrolytes)
(Blood urea &/or renal function) or (urea [& serum level]) or (urea and electrolytes)
(blood urea &/or renal function) or (urea [& serum level]) or (urea and electrolytes)