The reagent that is about to run out

It is the second Tuesday of the month. Chemistry has 8 packs of high-sensitivity troponin I reagent on the shelf, and the analyzer is consuming reagent faster than the shelf is being restocked. A supply-disruption notice just arrived from the manufacturer: shipments are capped at 60% of this laboratory's historical order for the next two ordering cycles. Nobody delayed an order. Nobody miscounted. The gap opened because forecasting, reorder timing, and a shortage on the supply side all landed in the same month.

Laboratory resource management requires the calculation and judgment that keep the troponin assay, and every other assay on the bench, supplied, staffed, and affordable when supply falls short. A laboratory must forecast resources, prevent stockouts and waste, and explain the operational consequences of its budget choices.

Build a monthly reagent forecast from patient volume plus QC, calibration, and repeat testing; calculate a reorder point and safety stock from lead time and demand variation; separate fixed cost from variable cost in a per-test price; compare owning an instrument to a reagent-rental proposal; and recommend a bounded, safety-first response to the shortage notice above, with assumptions stated.

A stockout is rarely a single mistake. It usually reflects an optimistic forecast, unmeasured non-patient consumption, a reorder point set too low, and no contingency plan arriving together.