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 Start by providing appropriate sedation. Fentanyl and propofol are given to the patient, ideally as an infusion, and titrated so the patient is motionless, without cough or gag, when palpating the trachea. If hypotension develops, the decision to provide fluids, vasopressors, and to continue the procedure are made jointly between the surgeon and anesthesiologist. Paralysis is not a requirement for this procedure and is reserved for those patients with movement despite adequate sedation.

 After sedation is achieved, a roll is placed midline under the scapula to facilitate hyperextension of the neck (Figure 6.1). The head is ideally hanging in air unless you place a pillow underneath. This positioning may arouse the patient if they are not adequately sedated.

 Prepare the PDT kit (Figure 6.2): test the tracheostomy tube (TT) cuff for patency, and remove all air after testing; adequately lubricate the TT and trochanter; prepare the guidewire; fill the subcutaneous and catheter syringes with 1% lidocaine/epinephrine; and hydrate the dilator with saline flush.

 Increase the oxygen to 100% FiO2; suction the endotrachea (ET) and mouth for secretions; clean the anterior neck and inject lidocaine/epinephrine subcutaneously two fingers above the sternal notch and midline. The respiratory therapist then deflates the ETT cuff while increasing the tidal volume to compensate for creating a leak (add 100 mL to the tidal volume).

 Palpate your needle puncture point at two fingers above the sternal notch and two cartilage rings below the cricoid cartilage. The needle is advanced in a perpendicular position midline on the trachea.At the midline position of the trachea there is no muscle or vasculature. The sternocleidomastoid, sternohyoid, and sternothyroid are lateral. A puncture too high will result in difficulties with the cartilage; too low may result in erosion of the tracheostomy tube into the innominate artery creating a fistula.

 Advance the needle while pulling on the syringe filled with 1% lidocaine and epinephrine. When air is drawn into the syringe you have entered the trachea.Aspiration of air confirms intraluminal tracheal placement. Entering the ET is a possibility; however it would require an extraordinary effort in piercing during the needle insertion. More likely you are in the trachea where the needle tip may be scratching the ET surface. The cuff may be ruptured at this point, but you should simply proceed. Adding to the tidal volume earlier should maintain ventilation.Immediately ‘anchor’ the needle by placing your fingers at the junction of the needle and the skin of the neck to avoid dislodgment. Inject 5 mL of the 1% lidocaine/epinephrine solution.Repeatedly reaffirm placement by demonstrating air bubbles during the procedure, especially if there is dislodgment from movement or otherwise. At any time if the location of needle is of concern start the procedure again, including palpating the trachea as above.

  Once the needle is touching the ET, the respiratory therapist pulls the ET back and forth which leads to tugging the needle in your fingers and affirming your position on the ET (Figure 6.3A).The ET is then gradually pulled to the 20 cm mark or when you no longer feel the ET any more (Figure 6.3B), usually between 18 and 19 cm.

 Angle the needle caudally and pass the catheter. It should pass easily into the trachea.If there is immediate resistance to advancing the catheter, you may not be in front of the ET, or possibly in a blind pouch. Return the needle to the perpendicular position; reaffirm position with air bubbles and have the respiratory therapist pull the ET slightly further cephalad. Retry passing the catheter as above.The guidewire is now advanced into the trachea and should pass freely, inducing a cough when at the bifurcation. At this point, bronchoscopic or US confirmation can be performed (Figure 6.4).

 Using the scalpel, make a perpendicular cut longitudinally, next to the guidewire, above and below it. The single straight dilator follows, opening the tracheotomy, after which blood‐tinged secretions may be seen bubbling through the incision. The plastic guidewire is placed over the metallic guidewire followed by the tapered dilator. The tapered dilators are marked to identify the level of dilation fitting the sized tracheostomy tube to be placed; proceed slowly with continued effort as you are dilating.Ultrasonography prior to the procedure reviews the anatomy and assesses for anomalous vasculature that risks bleeding. It may also be of benefit in confirming the guidewire presence in the tracheal lumen. This is especially helpful if any questions arise during the procedure, so ultrasound should be available at the time of the procedure. This can also be done by bronchoscopy.

 Once fully dilated, the TT is inserted over the guidewire left in place once the dilator was removed. Again, maintaining the patient in the fully extended position is key to performing this step smoothly.

 Remove the trochanter from the TT, replace it with the inner cannula and connect to the ventilator. Do not extubate unless the patient is receiving full tidal volumes on the ventilator (remember air escaping from the ET may falsely diminish tidal volumes); listening to breath sounds and assessing O2 saturation and end‐tidal CO2 will help verify TT placement.

 Remove the ETT, suture the TT in place and order a CXR to rule out PTX.