The endotracheal tube is pulled back under ultrasound guidance until the cuff is at the level of the thyroid cartilage, thus avoiding puncture of the cuff. The cricoid cartilage is palpated, and a 1.5 cm vertical incision is made immediately below that point. The subcutaneous tissue is bluntly dissected with hemostats until the pretracheal fascia is exposed. The trachea is punctured between the first and second, or the second and the third tracheal rings with a 14 G intravenous catheter needle (Jelco®; Medex, Carlsbad, CA) attached to a fluid filled 10 cc syringe, under ultrasound guidance. As soon as aspiration of air into the syringe is confirmed, the intravenous catheter is advanced into the trachea

and the needle is removed. A flexible guidewire is gently passed Smad inhibitor through the intravenous catheter into the trachea; the catheter is removed afterwards (Figure 3). Ultrasound is once again used to verify endotracheal positioning of the guidewire. A threaded dilator (6 mm

internal diameter) is advanced into the trachea, over the guidewire, for approximately 1 cm by clockwise rotation; minimal pressure PCI-32765 manufacturer is exerted on the anterior tracheal wall (Figure 4). The threaded dilator is removed by counter clockwise rotation after air escape through the lumen is detected. A self-retaining retractor forceps, with a limiter ridge, is passed over the guidewire into the trachea in locked position. The retractor is AS1842856 opened to enlarge the tracheal breach laterally, and to maintain the tracheal orifice open (Figure 5). A flexible, spherical tip introducer (6 mm internal diameter) is inserted into the airway under direct vision, facilitated by the retractor which is removed afterwards (Figure 6). A tracheostomy tube is placed inside the trachea passing over the guidewire and the flexible Benzatropine introducer (Figure 7). At this point the flexible introducer and the guidewire are removed, the cuff is inflated, and the patient is ventilated via the tracheostomy tube. The endotracheal tube

is completely removed after adequate ventilation is confirmed by end-expiratory volume on the ventilator and auscultation of the patient. The tracheostomy cannula is secured in place with a neckband, and a chest radiograph is performed. Statistical analysis was performed using Graph Pad Prism (GraphPad Prism Software, Inc., San Diego, CA). Data are reported as the mean ± SEM and percentages. Figure 2 Ultrasound image of the trachea. Longitudinal view of the trachea shows the cricoid cartilage and the tracheal rings; important anatomical references to localize the site of puncture of the trachea. The endotracheal tube has been pulled back. I, II, III (first, second, and third tracheal rings); image obtained with an 8 MHz vascular probe. Figure 3 The guidewire in position. The guidewire is passed into the tracheal lumen through the 14 G intravenous catheter. Figure 4 The threaded tip dilator.