Powder, Cartridge or Pad: A Per-Patient-Day Cost Table for a 35-Bed Unit

Three quotes land on the same desk in the same week. A 25 kg sack of gel powder at 7.20 pounds a kilo. A gel cartridge system at 0.85 pounds per cartridge plus a holder at 34 pounds. And absorbent pads at 0.28 pounds each, four to five a day. The unit has 35 beds at 94 per cent occupancy. The purchasing officer has to recommend one, and the three quotes are not remotely comparable as they stand.

This article builds a per-patient-day cost model that includes the things the quotes leave out: staff minutes, disposal weight, laundry and the cost of a leak. The numbers are illustrative, but the structure is the one to copy into a spreadsheet.

Setting the denominator first

Occupied bed-days, not beds. Thirty-five beds at 94 per cent occupancy over 365 days is 12,007 occupied bed-days. Every consumable figure must be divided by that number, or the comparison flatters whichever option is quoted per case rather than per patient.

Then fix the clinical assumptions: one gelling event per patient per day on average, 420 ml per event, and a 20 per cent subset producing above 700 ml. Get these from the urine output charts for a fortnight rather than from a supplier’s case study.

The three columns, fully loaded

Powder. 9 g per event at 7.20 per kilo is 0.065. Sachet or scoop handling at 40 seconds of carer time at 13.20 per hour is 0.147. Disposal adds about 0.9 kg per patient-day at 0.045 per kilo, so 0.04. Total 0.25 per patient-day, or roughly 3,000 pounds a year for the unit.

Cartridge. One cartridge per event at 0.85, handling 15 seconds at 0.055, holder amortised over three years at 0.003 per patient-day, disposal 0.05. Total 0.96, or 11,500 pounds a year. The appeal is not cost; it is that a cartridge cannot be under-dosed and does not produce dust.

Pad. Four changes a day at 0.28 is 1.12, at three minutes each is 0.66 in staff time, plus laundry at 0.21 per pad-day and disposal at 0.06. Total 2.05, or 24,600 pounds a year. Pads also carry a skin-integrity cost that never appears on the invoice but does appear in tissue viability reports.

Where the model breaks

Three sensitivities matter more than the base figures. First, volume: a unit with a high proportion of catheterised patients at 1.5 litres per collection doubles the powder cost per patient-day, because the dose scales with litres and the handling time does not. Second, agency staffing: at 40 per cent agency hours, the rework rate on powder rises, and the cost of a single leaked container (linen, carpet, staff time, incident report) is 60 to 180 pounds.

Third, waste route. If the unit discharges to a macerator, cartridges and pads become a maintenance liability as well as a cost. If it sends everything to clinical waste, the disposal line dominates and powder wins by an even wider margin because gel weighs less than a saturated pad.

What the recommendation should say

The honest answer for most 35-bed units is powder as the default with cartridges reserved for the rooms where dosing reliability is the binding constraint, typically eight to twelve beds with high turnover or complex needs. That hybrid usually lands at 0.34 per patient-day, spends 4,100 pounds a year, and removes the two failure modes that generate complaints.

Put the model in the tender response and ask each supplier to populate the staff-time column with their own handling estimate. A supplier who claims zero handling time has told you they have never stood in a sluice at 3 a.m.

What to hold back for the second year

Build in a volume growth assumption of 3 to 5 per cent and a review trigger if average collection volume moves by more than 100 ml. Both are cheap to write into the contract and both prevent the familiar argument in month fourteen about why consumption is 30 per cent above forecast.

To populate the consumable column properly you need a landed price per kilo at your delivery point, not a list price. We quote delivered against a twelve-month volume forecast with the absorption specification attached, and the grade options are set out at the urine gel powder product range.