6.1 Instrument Make-Up for Various Sets

Sets Are Built From the Operation Backwards

Every instrument set answers a predictable series of surgical needs:

1. Incise — scalpel handles and blades
2. Expose — retractors sized to the depth of the field
3. Dissect — scissors and dissecting clamps
4. Achieve hemostasis — hemostats in the numbers the tissue demands
5. Grasp and hold — tissue forceps and graspers matched to the tissue
6. Suture — needle holders sized to the needles
7. Suction and accessory — suction tips, towel clips, sponge forceps
8. Specialty — the instruments unique to the procedure

If you can name the operation, you can predict most of the tray. That predictive ability is exactly what lets a specialist notice that a Bookwalter blade has ended up in a minor set or that a total joint tray is short its acetabular reamers without reading every line of the count sheet first.

---

General Sets

---

Specialty Sets Layer Onto a Core

Most specialty trays are a general core plus a procedure-specific layer. Recognising the two layers makes an unfamiliar tray tractable.

---

Why Standardization Matters

A standardized set is one whose contents are fixed, documented, and identical across every copy of that set in the facility.

Standardization delivers concrete benefits:

• Fewer errors. An assembler builds the same tray the same way every time, and deviations become visible.
• Faster assembly and faster case set-up.
• Lower inventory cost. Facilities routinely find that sets contain instruments that are opened, contaminated, reprocessed, and never used — every one of which costs money on every case.
• Reliable counts. A fixed list is what makes a numeric count meaningful.

Set changes are therefore formal: a request from a surgeon or the OR, review by SPD and the OR governance group, a documented revision to the count sheet with a version and date, updating of the tracking system, and communication to every assembler. An assembler must never change a set list at the table — adding, deleting, or substituting an instrument on personal judgement defeats the entire point of standardization and creates a set that does not match its own documentation.

---

Reading a Set the Way a Specialist Does

When an unfamiliar tray arrives, ask:

1. How deep is the field? Long instruments mean a deep cavity; short instruments mean superficial.
2. What tissue? Atraumatic jaws mean vessel or bowel; toothed jaws mean fascia or tissue to be removed; bone clamps mean orthopedic.
3. What is the specialty layer? The unfamiliar instruments almost always belong to one procedure family.
4. What is missing that ought to be here? A laparotomy set with no self-retaining frame, a needle holder set with no fine holder, a suction with no stylet.

That fourth question is the specialist's real contribution. Anyone can count to the number on the sheet; recognising that a set is numerically complete but functionally wrong is what the credential is for.

Peel-Pack, Tray or Container: A Configuration Decision

How an instrument is packaged is part of set make-up, and the exam treats it as a decision with rules rather than a matter of convenience.

Peel pouches suit small, light, individually used items — a single scissor, a spare hemostat, a specific forceps. They are not appropriate for heavy items, which tear the seal, or for large multi-instrument groups, which prevent sterilant contact. When a pouch is used inside a tray, it should be placed so it is not crushed, and pouch-within-pouch is generally discouraged because it interferes with drying and sterilant penetration.

Wrapped trays and rigid containers carry full sets. A rigid container brings its own requirements: gaskets inspected for integrity, filters correctly installed and of the right type, latches functional, and the container itself free of dents that break the seal path.

The practical judgement the specialist makes is whether a set has grown so large that it should be split into two trays. Weight, drying performance, and the fact that opening one enormous tray to obtain one instrument wastes the whole set all push toward splitting; the counter-pressure is that more trays mean more processing and more count-sheet maintenance.

Core Sets, Add-Ons and Supplemental Peel-Packs

Most departments build inventory as a core set plus specialty add-ons rather than as dozens of independent complete sets, and understanding this structure explains a great deal about how count sheets are written.

A major or laparotomy set provides the general instruments almost every open case needs. A specialty procedure then adds a specialty tray — vascular, thoracic, GYN — that contains only the instruments unique to it. Frequently requested single instruments are held as supplemental peel-packs so the surgeon can obtain one item without opening a second full tray.

This structure controls inventory cost and processing load, but it makes the count sheet the single point of truth: if the core set silently changes, every specialty case built on it is affected.

Standardisation Versus Surgeon Preference

Sets exist in tension between standardisation, which reduces error and cost, and individual surgeon preference, which improves the surgeon's efficiency. The resolution used in practice is a standardised base set with preferences handled through preference cards and supplemental packs rather than through a separate full tray per surgeon.

When a surgeon requests a permanent change to a set, the change belongs in a controlled process: the count sheet is revised, the tray is relabelled, staff are informed, and the old sheet is withdrawn. An undocumented change made at the bench is how two trays with the same name end up containing different instruments.