4.5 Surgical Draping Principles and Sequence

Surgical Draping Principles and Sequence

Quick Answer: Surgical draping establishes and maintains the sterile field around the incision site. Core principles: always cuff drapes over sterile gloved hands to protect fingers, drape from clean incision toward unsterile periphery, drape the near side first before reaching across (or walk around the table), never adjust or pull a placed drape toward the incision, treat any drape falling below table level as non-sterile, use impermeable barrier materials to prevent strike-through contamination, and secure lines with non-perforating clips.

Draping is the final step in preparing the operative field before the surgical incision. The drape serves as a physical barrier that prevents the migration of microorganisms from the patient's unprepared skin, hair, and non-sterile environment into the open surgical wound.

1. Drape Materials & Barrier Performance Standards

Under AAMI (Association for the Advancement of Medical Instrumentation) PB70 Standards, surgical drapes and gowns are classified by their liquid barrier performance:

Material Characteristics

• Non-Woven Synthetic Drapes: Single-use disposable drapes composed of spunbond-meltblown-spunbond (SMS) polyolefin fibers. They provide high tensile strength, lint-free characteristics, fluid repellency, and flame resistance.
• Woven Reusable Fabrics: Tightly woven cotton/polyester blends treated with chemical fluorocarbon water-repellent finishes. They lose barrier effectiveness after repeated laundry/sterilization cycles and require tracking.
• Plastic Adhesive Incise Drapes (e.g., Steri-Drape, Ioban): Thin, transparent, fluid-impervious polyethylene film with an adhesive backing. Applied directly over prepped skin; incisions are made directly through the film. Ioban drapes contain iodophor impregnated directly into the adhesive layer for continuous antimicrobial activity.
• Strike-Through Contamination: The phenomenon where liquid (blood, irrigation, body fluid) penetrates through a permeable drape, creating a continuous wicking pathway for microorganisms to travel from unsterile surfaces beneath the drape up to the sterile field.

2. Classification of Surgical Drapes

                           SURGICAL DRAPE TYPES

   1. UTILITY TOWELS                  2. LAPAROTOMY FENESTRATED SHEET
      +-----------------------+          +-----------------------------------+
      | (4 Blue Towels to     |          | [Head / Anesthesia Screen Shield] |
      |  square off incision) |          |-----------------------------------|
      +-----------------------+          |         [ FENESTRATION ]          |
                                         |-----------------------------------|
   3. EXTREMITY SHEET                    | [Body / Leg Extension Cover]      |
      +-----------------------+          +-----------------------------------+
      |  (Elastic Cylindrical | 
      |   Aperture for Limb)  |       4. SPLIT / U-DRAPE
      +-----------------------+          +-----------------------------------+
                                         | [Base] \\\\\\ [Tails wrap around] |
                                         +-----------------------------------+

• Fenestrated Drapes: Contain a reinforced window (fenestration) tailored to specific anatomical structures:
  • Laparotomy Sheet: Longitudinal rectangular fenestration for abdominal midline incisions.
  • Thyroid / Neck Sheet: Small transverse or oval fenestration with an attached fluid-catch pouch.
  • Chest / Thorax Sheet: Large window for sternotomy or lateral thoracotomy.
  • Craniotomy Sheet: Oval fenestration with a 360-degree fluid collection bag and drainage suction port.
  • Perineal / Lithotomy Sheet: Fenestration with attached full-length leggings.
• Extremity Drapes: Heavyweight sheets with an integrated round elastic aperture that stretches snugly over fingers, toes, or a limb to form a tight, leak-proof fluid seal.
• Split Sheets & U-Drapes: Feature a deep longitudinal "U" cutout creating two long tails. Used to drape around extremities, the neck, shoulders, or hips.
• Equipment Drapes: Form-fitted sterile transparent polyethylene covers for operating microscopes, C-arm fluoroscopy units, robotic arms, ultrasound probes, and video camera cables.

3. Fundamental Rules of Surgical Draping

1. Maintain Controlled Distance: Stand at a safe distance (minimum 12 inches) away from the unsterile operating table while unfolding drapes.
2. Cuff over Gloved Hands: Always turn the edge of the drape back over your sterile gloved hands to form a protective cuff. This prevents sterile fingers from inadvertently touching the patient's prepped skin or non-sterile equipment.
3. Drape from Clean to Dirty: Place drapes directly over the prepped incision site first, and unfold outward toward the periphery.
4. Near Side First: When applying utility towels or split sheets, drape the side closest to you first, or walk around the table to drape the far side. Never reach across an unsterile operating table.
5. Hold Drapes High: Hold drapes elevated until positioned precisely over the target anatomy, then drop and smooth gently. Never drag a drape across unsterile surfaces.
6. Never Reposition Toward the Incision: Once a drape has contacted a surface, it must NEVER be shifted, pulled, or adjusted closer to the incision line. Moving a drape inward drags non-sterile peripheral skin flora directly into the surgical field. If a drape is misplaced, it may only be shifted away from the incision or discarded completely.
7. Below Table Level is Non-Sterile: Any portion of a drape extending below the level of the table mattress is strictly non-sterile. Never reach below table level to retrieve a dropped drape edge.
8. Towel Clamps: Use non-perforating clips (e.g., Lorna/Edna clamps) to secure electrosurgical cords and suction tubing to drapes. If a perforating clamp (e.g., Backhaus) punctures a drape, its tips are contaminated; if relocated, pass the clamp to the circulator without touching the tips, and cover the puncture site with a sterile impervious patch.

4. Step-by-Step Draping Procedures by Specialty

                   4-TOWEL LAPAROTOMY SQUARE-OFF SEQUENCE

                               [ 1. SUPERIOR ]
                               +-------------+
                               | (Cuffed)    |
                               +-------------+
             [ 3. LATERAL NEAR ]             [ 4. LATERAL FAR ]
             +-----------------+ [ INCISION ]+-----------------+
             | (Cuffed)        |   SITE      | (Walk around or |
             +-----------------+             |  reach with     |
                               +-------------+  cuff)          |
                               | (Cuffed)    +-----------------+
                               +-------------+
                               [ 2. INFERIOR ]

1. Abdominal Laparotomy Draping Sequence

1. Square Off with Four Utility Towels:
   • Fold a 2-inch cuff on each blue surgical towel.
   • Place Towel 1 superior to incision; Towel 2 inferior to incision.
   • Place Towel 3 on the lateral side closest to the scrub technologist.
   • Place Towel 4 on the far lateral side (walk around table or pass to surgeon).
   • Secure towel corners with non-perforating towel clips, skin staples, or adhesive strips.
2. Apply Incise Drape (Optional): Remove backing paper; stretch smoothly over the squared-off window without air bubbles.
3. Apply Laparotomy Sheet:
   • Place folded drape directly over the center of the squared incision window.
   • Orient the patient graphic toward the head/feet.
   • Unfold the top half cephalad over the anesthesia screen; unfold the lower half caudad over the patient's feet; extend armboard flaps laterally.

2. Lower Extremity (Orthopedic) Draping Sequence

1. Place an impervious down-sheet beneath the elevated extremity.
2. Scrub assistant holds the foot/toes while elevating the limb.
3. Roll a sterile tubular impervious stockinette up the extremity past the operative site; secure with an elastic Coban or Ace bandage.
4. Slide an extremity sheet over the foot and pull proximally until the elastic aperture seats firmly above the operative knee/joint.
5. Apply split sheets or U-drapes around the proximal thigh/tourniquet as needed.

3. Lithotomy / Perineal Draping Sequence

1. Under-Buttocks Drape: Fold a cuff over sterile hands; slide beneath the patient's sacrum while the circulator elevates the buttocks.
2. Sterile Leggings: Hand one legging to the surgeon/assistant; cuff hands inside the opening and slide the legging smoothly over the stirrup boot and leg up to the groin.
3. Perineal Sheet: Unfold the fenestrated perineal sheet over the abdomen, pelvis, and stirrups.

5. Postoperative Drape Removal Protocols

• Prior to drape removal, all sharp instruments, clamps, sponges, and heavy hardware must be removed from the drapes and transferred to the back table.
• Apply the sterile surgical dressing to the closed incision.
• The sterile surgical technologist holds the surgical dressing firmly in place with a sterile gloved hand while the circulating team gently releases the drapes.
• Roll drapes inward and away from the patient's face, trapping blood, bodily fluids, and disposable paper within the center of the drape.
• Dispose immediately into marked biohazard waste containers.