17 December 2014 (Wednesday) - Chloride
The NICE clinical guideline 'Intravenous fluid therapy in adults in hospital' (CG174) recommends daily serum chloride monitoring in patients receiving intravenous fluids with chloride concentrations greater than 120 mmol/L, including 0.9% ('normal') saline.
To facilitate this, all inpatient requests for serum electrolyte and creatinine measurements will automatically also have a serum chloride measured and reported.
Up until now chloride has been something of an obscure add-on. Generally chloride levels go up and down with sodium levels, so measuring chloride is a good way to spot an “iffy” sample.
Having said that, I really need to bone up on the topic.