This patient is likely to have a prolonged course of mechanical ventilation due to neurologic failure and should undergo tracheostomy. Although prolonged endotracheal intubation with a modern high-volume, low-pressure cuffed tube is safe, rarely resulting in subglottic stenosis or vocal cord injury,^1,2 tracheostomy offers several advantages in patients with severe brain injury.^3,4 These include facilitation of weaning from mechanical ventilation,^5,6 prolonged access to the lower airways for secretions management, improved comfort,^7-9 and earlier mobilization for physical and occupational therapy.¹⁰ Tracheostomy often makes possible discontinuation of sedating medications,^9,11 facilitating neurologic examination, and may allow brain-injured patients with good cardiopulmonary function to be completely disconnected from mechanical ventilation, preventing the common complications of atelectasis and respiratory muscle atrophy. Disadvantages include peri-operative and long-term complications of the procedure and introduction of a potential reservoir of bacterial colonization into the airway. General indications for tracheostomy in the neurocritically ill are presented in Table 45-1.

Optimal timing of tracheostomy in all patient groups is controversial. The benefit of early tracheostomy in neurocritical care is debatable, with conflicting results from multiple studies,^12-15 but has a trend toward benefit in all populations.¹⁶ A meta-analysis suggested benefits to early tracheostomy in patients expected to receive mechanical ventilation for prolonged periods,¹⁷ or those with infratentorial lesions.¹⁸ Multiple retrospective studies suggest clinical and economic benefit when tracheostomy is performed before day 7, compared with delayed tracheostomy.^19-23 A recent multicenter randomized controlled trial showed a nonsignificant trend toward less ventilator-associated pneumonia in critically ill patients randomized to early tracheostomy compared with prolonged mechanical intubation, and the secondary outcome measures of ventilator free days, ICU free days, and survival to ICU discharge favored early tracheostomy (Table 45-2).²⁴ Recent trauma guidelines suggest early tracheostomy for patients with severe TBI,² and a pilot trial in patients with severe stroke and respiratory failure (SETPOINT trial) showed lower mortality in the early tracheostomy group;²⁵ a multicenter trial is now underway.

Open surgical tracheostomy, and to some degree modified percutaneous tracheostomy (PT), offer direct visualization and palpation of the anatomical structures of the anterior neck; however, a pure percutaneous technique relies on careful planning and palpation, familiarity with neck anatomy (Figures 45-1 and 45-2), and sometimes ultrasound and/or bronchoscopic guidance for optimal results. All three techniques are supported by decades of clinical experience, and the experience of the surgeon or proceduralist^26,27 has been shown to be a more important factor in preventing complications than the technique used or subspecialty of the physician.^28-30

Tracheostomy is typically performed between the 2nd and 3rd tracheal rings, well above the innominate artery, and below the thyroid isthmus (Figure 45-2). Major vessels traverse the anterior neck, including the innominate, inferior thyroid, and carotids, and significant anatomical variance in these structures is present within the population. Accidental puncture of large arteries and veins can be averted by routine ultrasonographic imaging prior to the procedure,^31,32 especially in obese patients. The surgical field should always be carefully palpated prior to incision and cannulation, but anatomically variant veins will be detected in only the thinnest patients without dissection or ultrasonographic imaging.

The rigid cricoid cartilage can be palpated and lies just inferior to the vocal cords. At the base of this structure, typically superficial and easily palpated, is the cricothyroid membrane—the preferred location for an emergent surgical airway in nonintubated patients because of its proximity to the skin. Tracheostomy is performed lower, because of the potential for laryngeal injury with cricothyroidotomy and the tendency for a higher tracheostomy to interfere with laryngeal function. The anterior tracheal wall is cartilaginous and is formed by 18 to 22 rings, whereas the posterior trachea is membranous, thin, and separates the trachea from the esophagus. When tracheomalacia is present, the trachea is collapsible, and anterior and posterior tracheal walls appose under downward pressure, so that bronchoscopic guidance or an open surgical technique should be employed to prevent esophageal injury or paratracheal placement and to facilitate the procedure.³³

Tracheostomy Tube Selection

Clinicians should carefully consider the type and size of tracheostomy tube to be placed. In the obese, a tube with inadequate depth is at risk of becoming dislodged, resulting in loss of the airway, or may become posteriorly angulated in the neck, resulting in partial airway occlusion against the tracheal wall and increasing the risk of suction trauma and subsequent granulation tissue formation and tracheal stenosis. Conversely, thin patients whose tracheostomy tubes are overlong may suffer erosion of the stoma due to angulation and pressure causing soft tissue erosion and increasing the risk of tracheoinnominate fistula. In all cases, a midline insertion and appropriate angle within the airway are least likely to result in tracheal complications. Different commonly employed tubes have dramatically different inner and outer diameters, angulation, depth, and length. Tracheostomy tubes with fenestration (for speech), with variable ventilator interfaces, with and without cuffs, with adjustable length, with armor, and with foam or air cuffs are all available from manufacturers, and familiarity with a variety of these products is advised.³⁴

PT and modified PT techniques are routinely performed by surgeons, and increasingly by anesthesiologists and intensivists of various backgrounds.^27-29 The procedure is considered an advanced airway technique, building on expertise in endotracheal intubation, bronchoscopy, and other guidewire-based percutaneous techniques. Multiple PT techniques^35-39 and commercially produced kits are available, and both the American College of Chest Physicians⁴⁰ and the European Respiratory Society⁴¹ have published guidelines for training and certification of competency, typically requiring a minimum number of procedures and a period of supervised apprenticeship. Tracheostomy should be performed by an experienced operator,^26,27 with a system in place to provide protocolized tracheostomy care and long-term follow up. Table 45-3 delineates elements of a successful PT program.

PT or modified PT performed at the bedside offers convenience and cost savings when compared with surgical techniques, with a similar safety profile.^29,42,43 In the brain-injured population, special attention should be paid to ICP, cervical spine injury, and strict preservation of metabolic and hemodynamic homeostasis during the procedure, issues that are described in greater detail below.

Procedural Technique

The neck is examined and anatomical features noted. Is the trachea easily palpated? Note the thyroid and cricoid cartilage, and the cricothyroid ligament (Figures 45-1 and 45-2). Are the cartilaginous rings easily palpated and rigid? Is the innominate artery palpable in or above the sternal notch, or are there thyroid anomalies that warrant further evaluation? Can the neck be moderately extended to bring the trachea closer to the skin surface? If obesity, deformity, or anatomical irregularity, prior tracheostomy, or other concerns exist, then ultrasonographic or CT evaluation may be necessary prior to the procedure.^31,32 Routine ultrasonographic evaluation to evaluate for variation in vascular anatomy should be considered.⁴⁴ Surgical marking pens are often used to define procedural anatomy prior to incising the skin.

The neck is prepared in sterile fashion, and the skin and subdermal tissues overlying the 2nd and 3rd cartilaginous interspace infused with a lidocaine-epinephrine mixture. After analgesia and sedation, a transverse incision is performed. In the pure percutaneous technique, the trachea is then cannulated between the 2nd or 3rd or the 1st and 2nd tracheal cartilages without blunt dissection, and a guidewire is inserted. In the modified technique, blunt dissection down to the trachea is performed, and the trachea is cannulated under direct visualization prior to guidewire insertion. The puncture can be performed under bronchoscopic or ultrasonographic guidance.^45,46 Although the bronchoscopic technique offers advantage of direct visualization and thus offers theoretical advantage of avoiding posterior wall puncture, ultrasonographic technique has been shown to be faster and does not require an additional bronchoscopist.^31,45,46 Not all proceduralists use bronchoscopic guidance to visualize the tracheal puncture,^29,47,48 but such visualization adds a measure of safety, especially when a pure percutaneous technique is used, in that tracheal placement is confirmed at the time of puncture, midline insertion is confirmed, and injury to the posterior tracheal wall or esophagus are avoided with certainty. PT can be performed with rigid bronchoscopic guidance in patients with complex airways, obesity, or coagulopathy.⁴⁹