75 year old NH resident presents following a fall at the nursing home.

He has severe hypernatraemiaNa  178

metabolic alkalosis  – HCO 30

probable additional metabolic acidosis due to exacerbation (normal K)/ new onset renal failure. (AG = 6)

renal failure with relatively high urea when compared to creatinine, possible severe dehydration.

Remember to look for causes of hypernatraemia and other causes of collapse in your workup.

The water deficit is calculated by using this formula

TBW (50% in males at average weight 70kg) = 35 X (Na -140/140)

Water deficit is 9.5 litres