3.6 Suction, Dilators, Probes & Accessory Instruments

Suction Tips

Three suction tips cover most of surgery, and each has a distinctive shape.

Frazier suctions are a chronic processing problem. The lumen is narrow and long, the angle makes brushing awkward, and the thumb port is a second, smaller lumen that is routinely missed. The stylet — a wire used to clear the lumen intraoperatively — is a separate countable component. It must be present at assembly, it must slide the full length of the lumen without binding, and it is a common source of "short set" discrepancies.

Frazier sizing is by French number stamped on the handle (commonly 7 Fr through 12 Fr). The size must remain legible; an unreadable stamp is a defect because the OR cannot confirm the requested size.

Dilators and Sounds

Dilator sets live or die by completeness and legibility. A dilator set missing one size is functionally incomplete even though nothing is broken, and this is precisely the "completeness of sets" scenario the exam's Ethics area tests. Sizes are checked at every assembly against the count sheet, and a dilator whose stamped size has worn illegible is removed.

Inspection also covers surface condition: dilators are inserted into tissue, so any burr, nick, scratch, or pit on the polished surface is a patient-injury risk and disqualifies the instrument.

Probes, Directors and Small Accessories

• Malleable (silver) probe: flexible wire probe with a bulbous tip for exploring a tract or fistula.
• Grooved director: a slotted guide over which tissue is divided safely.
• Ruler / measuring devices: markings must remain legible.
• Skin hooks (Joseph, Guthrie, Frazier): single, double, or multiple prong. Sharp hooks are checked for point sharpness and for straightness; a bent hook tears tissue.
• Nerve hooks / ball hooks: used in neuro and spine; checked for a smooth, unburred ball.
• Suture / ligature carriers: eye must be smooth so suture is not shredded.
• Trocars and obturators: matched pairs — a trocar with the wrong obturator is a set error and an insertion hazard.

Lumen Inspection: The Cross-Cutting Rule

Any instrument with a channel — suction tips, cannulas, trocars, dilators with irrigation ports, laparoscopic shafts, sump tubes — carries an elevated cleaning-failure risk because the interior cannot be inspected by simply looking at the outside. The specialist's expectations are:

1. Brush of the correct diameter and length. A brush that is too small does not contact the wall; a brush that is too short never reaches the far end. Brushes are inspected for worn or missing bristles and are themselves cleaned and disinfected or discarded per policy.
2. Brush all the way through, not back and forth partway. The brush must exit the far end so soil is pushed out rather than repositioned.
3. Flush after brushing, under water where the IFU allows, to avoid aerosolising contaminants.
4. Verify patency — confirm flow through the full lumen and, where the device allows, confirm visually with a borescope or by passing the stylet.
5. Dry the lumen with filtered compressed air where permitted; retained moisture is a corrosion and wet-pack source.

Lumened devices are also the instruments most often cited in cleaning-verification audits, which is why the Inspection content area separates "inspection for cleanliness — frequency" from "inspection for cleanliness — method." Both are covered in Chapter 7.

Named Suction Tips and Where They Belong

Suction devices are identified by tip design, and each design is tied to a field, so recognising the tip usually tells you the set it came from.

The Yankauer is the familiar rigid tip with a bulbous, sometimes fenestrated end, used for general and oral suctioning. The Poole suction has a perforated outer guard over an inner tube and is used in the open abdomen, where the guard prevents bowel or omentum being drawn against the port; because it is two pieces, it is a frequent source of missing-component errors and must be disassembled for cleaning. The Frazier is a fine, angled tip with a thumb port used in neurosurgery, ENT, plastic, and spine work; the thumb hole lets the surgeon modulate suction, and a stylet is supplied to clear the lumen. The Andrews-Pynchon and Baron tips also appear on ENT trays.

Dilators, Sounds, Bougies and Obturators

These four terms are routinely confused and are all testable.

A dilator progressively enlarges an orifice or tract — Hegar dilators for the cervix, Van Buren sounds for the male urethra, Bakes dilators for the common bile duct. Hegar dilators are double-ended and graduated in millimetres, supplied in a numbered set, and the exam expects you to know that they are used in graduated ascending order. A sound is used primarily to explore, measure, or detect a calculus rather than to enlarge, though the two functions overlap in practice. A bougie is a slender cylindrical dilator, often flexible, used in the oesophagus or urethra. An obturator is the blunt-tipped rod inserted through a hollow instrument such as a trocar cannula or a proctoscope to allow atraumatic insertion, and is removed once in position.

Why This Group Fails Inspection More Than Any Other

Every item in this section either has a lumen, a graduated set membership, or both, and those are the two most common set-integrity failures.

Lumened items must be inspected with the lumen held to a light source or checked with a lighted magnification or borescope where the department has one, then flushed and confirmed dry. Retained soil in a Frazier tip is invisible from the outside. Graduated sets must be complete and in sequence: a Hegar set missing a single size is an incomplete set, and the ethical obligation is to hold the tray rather than send it with a gap that will be discovered mid-procedure.

Check plating on dilators for flaking, and confirm that stylets are present and matched to their suction tips.