2.3 Surgical Instruments & Handling

The Functional Categories

Instruments are classified by what they do, not by their shape, and the CST is tested on placing common named instruments into the right category. Each instrument also has anatomy worth knowing: the box lock (the hinge), the ratchet (the locking teeth near the rings/finger loops), the shank, and the jaws or tips.

Instruments are generally constructed of stainless steel, sometimes with tungsten carbide inserts (often marked by gold-handled rings) that grip and resist wear in needle holders and heavy scissors. The CST should also recognize ringed (finger-loop) instruments — hemostats, scissors, needle holders, clamps — versus non-ringed (thumb) instruments like forceps and retractors, because how an instrument is held determines how it is passed.

Distinguishing Look-Alike Instruments

Many instruments resemble one another and are distinguished by their tips and jaw serrations:

• Hemostats (clamping) have transverse serrations running the full length of the jaw and a fine tip — used to clamp small vessels. A Kelly is larger with serrations only on the distal half; a Crile has full-length serrations; a mosquito (Halsted) is the smallest.
• Needle holders look like hemostats but have short, stout jaws with cross-hatched serrations to grip a needle without letting it rotate.
• Tissue forceps are "pickups." Toothed forceps (Adson with teeth, rat-tooth) grasp tough tissue such as skin and fascia; smooth or DeBakey (atraumatic) forceps grasp delicate tissue such as bowel or vessels.
• Allis clamps have multiple fine teeth that grasp tissue to be removed; Babcock has a smooth, rounded, fenestrated jaw to encircle delicate structures like bowel or ureter atraumatically; Kocher/Ochsner has heavy teeth at the tip for tough tissue.
• Metzenbaum scissors are slender for delicate tissue dissection; Mayo scissors are heavier for cutting suture and tough tissue ("suture scissors").

Sharp vs. Blunt Dissection and Instrument Passing

Sharp dissection cuts tissue with a blade or scissors (scalpel, Metzenbaum). Blunt dissection separates tissue planes without cutting, using a sponge dissector ("peanut"/Kittner), a finger, or the back of a closed instrument. The CST anticipates which the surgeon needs at each step.

Correct instrument passing keeps the surgeon's eyes on the field:

• Pass instruments firmly into the surgeon's palm with a snap so they feel it land.
• Pass curved instruments so the curve matches the direction of use, with the ratchet closed once and the tip visible.
• Pass a scalpel with the blade pointed down and the handle toward the surgeon, or use a neutral/hands-free zone for sharps to reduce injury.
• Hand a needle holder with the needle pointed in the direction the surgeon will sew and the tip about two-thirds of the way back on the curve.
• Keep the Mayo stand and back table organized in order of use so anticipation is fast and counts are accurate.

Retractors, Scalpel Blades, and Instrument Care

Retractors expose the field and come in two families. Handheld retractors (Army-Navy, Richardson, Deaver, malleable/ribbon) are held by the assistant; self-retaining retractors (Weitlaner, Gelpi, Balfour, Bookwalter) hold themselves open with a ratchet or frame, freeing the team's hands. The CST matches the retractor to the depth and width of the wound — small Army-Navy for superficial work, deep Deaver or Balfour for abdominal cavities.

Scalpel blades mount on numbered handles, and the pairing is tested:

Blades are loaded and removed with a needle holder or hemostat, never the fingers, and the used blade goes into a sharps container.

Instrument care preserves function and sterility: instruments are kept free of blood and bioburden during the case (wiped with a moist sponge, lumens flushed), box locks are inspected, and at the end of the case they are decontaminated, inspected, and prepared for reprocessing. Damaged or malfunctioning instruments (a misaligned box lock, a dull blade, a sprung clamp) are removed from service. Anticipation, correct passing, organization, and care together let the surgeon work efficiently and safely.