经皮环甲膜切开术

Percutaneous cricothyrotomy is indicated when other forms of endotracheal intubation have failed and patient ventilation is declining or not possible—the "can't intubate, can't ventilate" scenario. It is the surgical airway procedure of choice in emergencies because it can be performed rapidly, even by less experienced practitioners, and has lower complication risks than alternatives.

The Seldinger technique involves introducing a device through an introducer needle and guide wire. The needle locates the target, the guide wire acts as a placeholder fed through the needle, and the device is advanced over the wire. In percutaneous cricothyrotomy, the needle identifies the airway, the guide wire secures the tract, and the catheter-dilator assembly is threaded over the wire into position.

Percutaneous cricothyrotomy using the Seldinger technique is preferred because it reduces bleeding risk and allows needle repositioning if the cricothyroid membrane is not encountered on first insertion. Open cricothyrotomy relies on visual identification after a vertical incision; if hemorrhage occurs, visualization becomes impossible, especially in obese patients or those with poor anatomic landmarks.

Palpate below the laryngeal prominence (Adam's Apple) to locate the cricothyroid membrane. Grab the paratracheal structures and move them as a unit; they create a depression. The needle insertion landmark is the midline of this depression. This anatomic approach works well even in patients with short necks or excessive soft tissue.

A standard pre-packaged kit includes an 18-gauge introducer needle, 5-milliliter syringe, scalpel, guide wire, dilator, airway catheter, and neck-tie. Additional supplies needed are chlorhexadine for skin prep, a bag-valve mask device, suction equipment, and oxygen supply. All components should be assembled and laid out before the procedure begins.

After securing the catheter with a neck-tie, confirm correct placement by auscultating for bilateral breath sounds and monitoring end-tidal CO2 levels, which should be in the normal range of 35-45 mmHg. These assessments verify that the catheter is properly positioned in the airway and that ventilation is adequate.

When a kit is unavailable, gather supplies from a central venous catheter tray: 5-milliliter syringe, introducer needle, guide wire, and scalpel. Obtain a tracheostomy tube and use it as the airway device. After needle aspiration confirms airway entry and the guide wire is advanced, make a horizontal incision and use the scalpel handle to dilate the opening before advancing the tracheostomy tube over the wire.