3.5 Procedural Supplies, Catheter Inventory, Surgical Instrumentation & Wound Closure

3.5 Procedural Supplies, Catheter Inventory, Surgical Instrumentation & Wound Closure

Task B8 — Align supplies and equipment with procedure looks trivial until the transseptal needle is opened and no matching dilator is on the field. The RCES specialist is the person who knows what a case will need before the operator asks, and the exam tests that inventory knowledge directly, along with surgical instrumentation, suture techniques and materials, wound closure, wound assessment, and wound healing from the published knowledge list.

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1. French Sizing and Catheter Dimensions

The French (Fr) scale measures circumference-derived outer diameter:

$\text{Outer diameter (mm)} = \frac{\text{French size}}{3} \qquad \text{French size} = \text{OD (mm)} \times 3$

The critical convention: a sheath's French size describes its inner diameter, while a catheter's French size describes its outer diameter. A 7 Fr catheter therefore passes through a 7 Fr sheath. The sheath's own outer diameter is roughly 1.5 to 2 Fr larger, which is what the vessel actually accommodates — a fact that matters when planning hemostasis for a 12 Fr ICE sheath.

Guidewires are sized by inch diameter (0.032", 0.035", 0.038") and by length in centimeters; the standard access wire is 0.035" × 145 cm, while extraction and exchange work uses 260 cm wires.

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2. The EP Lab Inventory

The specialist's operational discipline is to open the minimum sterile inventory and to keep the case-specific extras — a second transseptal set, a larger sheath, the pericardiocentesis kit — unopened but immediately at hand. Opened, unused disposables are pure cost; unavailable disposables during a tamponade are a patient safety event.

Sterile field maintenance rules that the exam tests:

• Only the top of a draped table is sterile; anything below table level is contaminated and is never brought back up.
• A gowned person is sterile from chest to sterile-field level, and from the hands to just above the elbow; the back is never sterile.
• Sterile packages are opened away from the body, and the last flap is pulled toward the opener.
• Wetness wicks bacteria — strike-through of a drape or gown contaminates it.
• Movement is face-to-face or back-to-back; sterile personnel do not turn their backs to the field or pass between two sterile fields.
• The circulator pours solution into a basin held at the field's edge without leaning over it.

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3. Surgical Instrumentation for CIED Implantation

Counts — sponges, sharps, and instruments — are performed before the procedure, before wound closure, and at skin closure, and a discrepancy triggers a search and a radiograph before the patient leaves the room.

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4. Sutures and Wound Closure

Suture size runs from largest to smallest as the number of zeros increases: 2-0 is thicker than 3-0, which is thicker than 4-0.

Monofilament versus braided is the exam's favorite distinction: braided sutures handle and knot better but have interstices that harbor bacteria, so monofilament is preferred where infection risk matters — precisely the CIED pocket. Silk remains the standard for lead anchoring sleeve ties because of its handling, and the tie is placed around the suture sleeve, never directly on the lead body, which would crush the insulation and conductor.

Closure techniques: interrupted (each stitch independent, tolerant of one failure), continuous/running (fast, even tension distribution), subcuticular (buried, best cosmetic result, no removal needed), purse-string, and the figure-of-eight (Z-stitch) used for immediate venous hemostasis around large sheaths in a fully anticoagulated patient. Alternatives include skin adhesive, adhesive strips, and staples.

Removal timing for non-absorbable skin sutures: face 3-5 days, trunk and upper extremity 7-10 days, and the pectoral CIED pocket typically 7-10 days.

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5. Wound Healing and Assessment

Healing categories: primary intention (clean, approximated edges — the normal pocket closure), secondary intention (left open to granulate), and tertiary/delayed primary intention (left open, then closed).

Post-procedure wound assessment documents: the incision line and approximation, drainage character and volume, surrounding erythema and its extent, induration, fluctuance, tenderness beyond expectation, and any dehiscence or exposed hardware.

Distinguish the two most-tested findings:

A pocket hematoma is the single strongest predictor of subsequent CIED infection, and the correct management is pressure, correction of anticoagulation where appropriate, and surgical evacuation if it is tense or expanding — never needle aspiration, which introduces organisms into a closed prosthetic space. Erosion or exposure of any part of the system mandates complete extraction of the generator and all leads; the device cannot be salvaged in place.

Healing is delayed by diabetes and hyperglycemia, corticosteroids and immunosuppression, malnutrition and low albumin, smoking, obesity, renal failure, radiation to the field, and continued anticoagulation with hematoma formation.