Electrolytes and Fluids

You are referred a 35-year-old female by the Emergency Department, who presented with a reduced level of consciousness. She has been intubated and ventilated and is haemodynamically stable.
 
Her CT brain is normal, and she is apyrexial.

A 54 yr old female is in ICU with sepsis after repair of a leaking ileo-colic anastamosis.  When you take over management on day 3, she is febrile and vasodilated.  T 38.5O C, pulse 110 / min, MAP 58 mm Hg. CVP 12 mm Hg. Urine output  15 mL/hr.

Management of hyponatremia

Biochemistry:  Candidates were asked to describe abnormalities and list possible aetiologies. Examples included hepatic and renal dysfunction, plasmacholinesterase deficiency (homozygous), an elevated osmolar gap, and a normal anion gap (renal tubular) metabolic acidosis.

Biochemistry. Examples included artefact secondary to contamination with potassium EDTA, a hypo-adrenal state, effects of alcohol/malnutrition, and rhabdomyolysis. Nine out of twenty-three candidates passed this section.

 Biochemistry.  Examples included a hyperosmolar state due to methanol poisoning, thrombotic thrombocytopaenic purpura.  The likely diagnoses and/or possible causes were requested, as were rationale or further tests.   Ten out of twelve candidates passed this section

Biochemistry. Examples included a hyperosmolar state, obstructive jaundice, and hyponatraemia. The likely diagnoses and/or possible causes were requested, as were formulae for some simple, relevant, calculations. Eleven out of fifteen candidates passed this section

Biochemistry including hepatocellular liver disease, cerebral salt wasting, and hyperglycaemia/hyperosmolar non-ketotic diabetic coma

Biochem profiles
GIT haemorrhage, rhabdomyolysism mannitol induced hypernatraemia, pyroglutamic acidosis (see CCM 2000; 28:1803-7)

Postoperative hyponatraemia and fitting