Tracheostomy Tube Placement

Early and Late Complications

Abstract

Tracheostomy tube placement is a therapeutic procedure that has gained increased favor over the past decade. Upper airway obstructions, failure to liberate from the ventilator, and debilitating neurological conditions are only a few indications for tracheostomy tube placement. Tracheostomy tubes can be placed either surgically or percutaneously. A percutaneous approach offers fewer surgical site infections and postsurgical bleeding than a surgical approach. A surgical placement posses a lower risk of injury to the posterior tracheal wall and spontaneous decannulation is less common. Late complications of both approaches include stenosis, malacia, along with tracheoesophageal, tracheoinnominate, and tracheocutaneous fistulas. This review describes the indications and methods of placement of tracheostomy tubes along with early and late complications that may occur following placement.

A tracheostomy is a surgical procedure during which a prosthesis (tracheostomy tube) is placed through a conduit created between the skin and the trachea. This conduit is called tracheostoma. Placement of a tracheostomy tube is performed to bypass airway obstruction, aid in the management of secretions, to a reduction of anatomic dead space, and to aid in weaning from mechanical ventilation in patients with chronic respiratory failure.

Complications of tracheostomy placement are infrequent, but can be life threatening. Patients requiring tracheostomy placement may have multiple comorbidities that can contribute to the risk of complication. The complications stemming from tracheostomy are divided into “early” and “late” depending on time from the procedure. Although the type and management of complications may vary greatly, it is essential that medical professionals have a solid understanding of tracheostomy complications to provide their patients with optimal care. This review outlines complications that may arise from tracheostomy placement, describes placement techniques, and cutting-edge approaches to treatment of complications arising from tracheostomy placement.

TRACHEOSTOMY TUBE PLACEMENT AND CARE

Tracheostomy tube placement can be performed surgically via open surgical tracheostomy (OST), or percutaneously via percutaneous dilational tracheostomy (PDT). PDTs are increasingly being performed at bedside in the intensive care unit rather than in operating rooms as there is no significant difference in postprocedure complications.^1,2 Procedure time is significantly decreased through placement with PDT and generally preferred over OST for elective tracheotomies.²The percutaneous approach performed with the single-step dilatation technique is more reliable than guidewire dilating forceps with regards to safety and success.³ In addition, observational studies suggest that preprocedure use of ultrasound and bronchoscopy appears to reduce periprocedural complications such as bleeding, posterior membrane laceration, and false tract formation.^4,5

Indications for tracheostomy placement using either the surgical or percutaneous approach include upper respiratory tract obstruction, prolonged ventilation, copious secretions, severe obstructive sleep apnea, and head/neck surgery (Table 1). Absolute contraindications for PDT include placement in pediatric patients, the presence of a midline neck mass, inability to palpate the laryngeal cartilages and tracheal rings, and uncorrectable coagulopathy. Relative contraindication for PDT include an unstable cervical spine, morbid obesity, anatomic distortion of the neck, previous neck surgery/radiation, active infection/burn/traumatic injury over neck, elevated intracranial pressure, significant ventilator requirements, and the need to secure the airway in an emergency situation in inexperienced hands.⁶

TABLE 1: Tracheostomy Indications

Appropriate timing of tracheostomy tube placement in critically ill patients requiring prolonged mechanical ventilation remains controversial. Most recent meta-analyses assert that early tracheostomy has no mortality benefit over late tracheotomy.⁷ Plastic (polyvinyl chloride or silicone) tracheostomy tubes are recommended as the initial tube. Removal or exchange of the tracheostomy tube should be performed at least 7 days following the initial tube placement. This point cannot be stressed enough as at least 7 days are necessary for the artificial stoma to mature. Attempts to place another tracheostomy tube into an immature stoma can be difficult and may lead to creation of a false lumen. In addition, appropriate care should be taken to ensure patency of the tracheostomy tube, including use of an inner cannula. The inner cannula should be cleaned daily to avoid mucous plugging.⁸Tracheostomy tube cuff pressures should be measured on a regular basis and should range from 20 to 25 mm Hg. Lower cuff pressures may lead to ineffective ventilation and aspiration, whereas high cuff pressure may result in mucosal ischemia and possible tracheal stenosis.

COMPLICATIONS

The potential complications of tracheostomy range from minor bleeding to life-threatening airway obstructions. The prevalence of complications related to tracheostomy do not vary significantly by race, ethnicity, or age.⁹ Complications of tracheostomy can be categorized as early or late. There are no exact guidelines to distinguish early complications from late complications, but more commonly the ones labeled as “early” are seen within 1 week of tracheostomy placement.

Early Complications

Early complications of tracheostomy are those occurring within the first week following placement, as the tracheostomy stoma takes approximately 1 week to mature. Stomal infections and bleeding are the most common complications following OST, while PDT has a higher incidence of injury to the posterior wall of the trachea. There is no significant difference in complications between PDT and OST² (Table 2).

TABLE 2: Tracheostomy Early Complications (<1 wk)

Bleeding

The incidence of major or minor bleeding following tracheostomy placement is 5.7%.¹⁰ While major bleeding during tracheostomy is rare, minor bleeding can be life threatening if it results in airway obstruction. Bleeding during tracheotomy or within first 48 hours is most commonly due to injury to superficial veins. Evaluation of the neck vasculature with ultrasound before tracheostomy can help reduce the incidence of early bleeding.⁴ Superficial bleeding can be easily treated with local measures such as packing, surgicel, gel foam, silver nitrate, or injection of lidocaine with epinephrine. Bleeding after 48 hours should always be thoroughly investigated as it can be the result of erosion of the tracheostomy tube into major vessels such as the innominate artery.

Stomal Infection

The incidence of surgical site infections following tracheostomy is 6.6%.¹⁰ Wound infection is more common in OST as compared with PDT.¹⁰Prophylactic antibiotics are not commonly recommended before tracheostomy placement. Appropriate wound care is generally sufficient for minor wound infection. Severe cases of necrotizing tracheal infection are rare and require oral tracheal intubation followed by debridement of involved tissue.

Subcutaneous Emphysema

The incidence of subcutaneous emphysema following tracheostomy vary from 0% to 5%.¹¹ Subcutaneous emphysema is caused by formation of a tissue tract anterior to trachea secondary to positive pressure ventilation or forced coughing against a tightly sutured or packed wound. Air driven by positive pressure ventilation can extend into to pleural space, leading to development of pneumothorax. This can be prevented by not suturing tissue around the wound tightly. Chest x-ray to identify subcutaneous air is recommended only when placement of the tracheostomy tube is technically challenging or in patients with signs and symptoms of subcutaneous air. Such complications are treated conservatively and are typically self-limited.

Posterior Tracheal Wall Injury

Injury to the posterior tracheal wall is a well-recognized and potentially fatal complication of tracheostomy placement. The incidence of posterior tracheal wall injury is higher in PDT compared with OST. The incidence of posterior tracheal wall injury varies from 0.2% to 12.5%.¹¹ Posterior wall injury commonly occurs due to poor control of the guidewire and guiding catheter.¹² Most posterior wall tears are small and heal without further intervention, whereas larger tears may present with airway bleeding, air leak around the tube, or into the mediastinum. Larger tears may be life threatening and require emergent surgical intervention. Surgical repair of large posterior wall injuries may require the use of cardiopulmonary bypass, which may not be possible in critically ill patients. The use of covered, self-expanding, metallic stents may represent a treatment option in patients with posterior wall tears who are not candidates for surgical repair. Placement of metallic stents can be performed at the bedside and have a lower complication profile. Postprocedure surveillance with flexible bronchoscopy is recommended following stent placement to identify the formation of granulation tissue, detect stent migration, and to identify infections, which may present as halitosis.¹³

Tracheostomy Tube Obstruction

Tracheostomy tube obstruction can be life threatening and requires immediate intervention. The incidence of tracheostomy tube obstruction following PDT has been reported to be 0% to 3.5%.¹⁴ Airway obstruction may result from plugging due to mucus or clotted blood. In addition, obstruction may occur following passage of the tracheostomy tube into a false lumen (paratracheal soft tissue) or due to angulations of tube orifices against the tracheal wall. Tracheostomy tube obstruction may present with acute deterioration of respiratory status and could result in death. Obstruction due to a mucous plug or blood clot can be relieved immediately by suctioning of tracheostomy tube. If the obstruction cannot be relieved, try exchanging the inner tube. Appropriate tube selection with correct size and horizontal length based on the patient’s anatomy reduces obstruction from the posterior tracheal wall. A long horizontal length is usually needed in obese patients. In addition, use of flexible bronchoscopy during tracheostomy tube placement can help prevent formation of false tracts.

Tracheostomy Tube Dislodgement

Tracheostomy tube dislodgement within 7 days of placement is a medical emergency. The absence of a mature tracheostomy tract may make replacement of the tube difficult and could lead to the creation of a false tract. A myriad of causes may lead to tracheostomy tube dislodgement, including loose tracheostomy ties, accidental displacement while turning patient, or self-extubation. The rate of tube displacement after PDT is approximately1%.¹¹ If the tracheostomy tube is accidentally dislodged, replacement of the tracheostomy tube using bronchoscopic guidance is encouraged in a timely manner (never blindly reinsert the tube). If the tracheostomy tube cannot be confidently reinserted, oral endotracheal intubation is necessary. To minimize the risk of this complication most experts will recommend suturing the flange of the tracheostomy tube to the skin in addition to the use of a tracheostomy tie.

Late Complications

Prolonged tracheostomy tube placement in critically ill patients with multiple comorbidities can lead to a number of late complications. The incidence of late complications following tracheostomy placement is approximately 65%.^15,16 Late complications are often divided according to their anatomic location in relation to the stoma as suprastomal, stomal, and infrastomal (Table 3) (Fig. 1).

TABLE 3: Tracheostomy Late Complications (>1 wk)

FIGURE 1: Anatomic locations of tracheostomy complications.

Suprastomal lesions are often a result of cricothyroidotomy, high tracheostomy tube placement, or friction of the superior aspect of the tracheostomy tube with the anterior airway wall in patients with significant kyphosis.^17,18 These lesions include subglottic stenosis, tracheal stenosis, and granulation tissue formation. We should also mention functional late complications such as functional voice changes and vocal cord dysfuntion.

Stomal lesions may result from fracture of the anterior tracheal wall following PDT. As a result, the anterior tracheal wall invaginates and protrudes into the tracheal lumen, resulting in a fixed obstruction.^18,19 Risk factors for stomal stenosis include sepsis, stomal infection, hypotension, advanced age, male sex, steroids, oversized tube, excessive motion, prolonged placement, and disproportionate excision of the anterior tracheal ring. Granulation tissue can also develop at the superior border of the stoma and usually is suspected when there is difficulty exchanging the tracheostomy tube.

Finally, infrastomal complications include tracheal stenosis, tracheomalacia (TM), tracheoesophageal, and tracheoinnominate fistulas. Infrastomal lesions typically result from ischemia of the tracheal mucosa due to endotracheal tube cuff balloon pressure exceeding the perfusion pressure (>25 mm of water).²⁰ Lesions caused by balloon expansion have decreased with the adoption of low-pressure, high-volume balloons.²¹ If ischemia is prolonged, it causes mucosal ulceration, followed by inflammation (chondritis) and necrosis in the mucosa and cartilage. This reaction stimulates the formation of a scar tissue, which obstructs the airways, resulting in circumferential stenosis.²⁰ Risk factors for infrastomal lesions include female sex, older age, prolonged duration, and excessive endotracheal tube cuff pressures. Malacia may also complicate the stenotic segment. The mechanism of malacia formation is not fully understood, but may be related to concomitant chronic airway inflammation secondary to bacterial colonization or acid reflux.²² Common signs and symptoms that may indicate late complications are unexplained difficulty in weaning from the ventilator, dyspnea on exertion, cough, hemoptysis, stridor. Flow-volume loop and computed tomography (CT) scan with 3-dimensional reconstruction can be used as screening tools, 2 months after decannulation.

Tracheal Stenosis

Tracheal stenosis describes a pathologic narrowing of tracheal lumen and can result from prolonged tracheostomy tube dependence. Tracheal stenosis is considered the most common late complication of tracheostomy tube placement. Some degree of tracheal stenosis is present in almost all patients with a tracheostomy tube, but only 3% to 12% of patients have clinically significant stenosis requiring intervention.²³ Tracheal stenosis is typically seen at the level of the tracheostomy stoma or suprastomally, but below vocal cords^20–24 (Fig. 2).

FIGURE 2: Bronchoscopic view of tracheostomy complications.

The pathogenesis of tracheal stenosis involves inflammation and the formation of granulation tissue. Trauma resulting from tracheostomy, mucosal ischemia due to excessive cuff pressures, persistent mucosal irritation stemming from the tip of tracheostomy tube, pooling of secretions, and gastroesophageal reflux disease are predisposing factors for development of ulceration and inflammation of cartilage, leading to the formation of granulation tissue. Subsequently, granulation tissue matures into a fibrous tissue layer covered with epithelium, leading to tracheal stenosis.²⁰ Patients with tracheal stenosis are often asymptomatic until the size of trachea has reduced to <5 mm or 25% to 50% of the original diameter.²⁴ Tracheal stenosis may be detected when the patient is still mechanically ventilated and can be clinically manifested as difficulty in weaning from the ventilator. Elevated peak airway pressures may be present for infrastomal stenosis. Dyspnea, stridor, and respiratory failure, may be present after decannulation. In addition, clinical manifestations of stenosis may present weeks to years after development, but typically are evident within 2 months following decannulation.²⁰

Flexible bronchoscopy remains the gold standard to diagnose and characterize lesions of tracheal stenosis.²⁵ Flexible bronchoscopy permits direct visual evaluation of the stenotic lesion. Airway lesions are described according to type, size, location, and degree of stenosis. Different types include A-shape (cartilage damage), simple, and complex stenosis. Size refers to the length in centimeters. Supraglottic, glottic, subglottic, and tracheal, are the locations. Distance from vocal cords, cricoid, and carina, are helpful. Degree of stenosis by quantifying percentage of obstructed lumen (grade I: <50%, grade II: 50% to 70%, grade III: 71% to 99%, and grade IV: 100%) (Fig. 2). Noninvasive testing such as pulmonary function testing is also sensitive in identifying fixed airway obstructions. Flow-volume loops permit localization and characterization of the obstruction. A stenosis outside the thoracic cage may show as blunting of the inspiratory limb of the flow-volume loop alone; and an intrathoracic obstruction would commonly show both inspiratory and expiratory blunting, resulting in a squared-off pattern. This method does not detect small changes in tracheal lumen in a diameter above 8 mm.²⁶ In addition, CT scans with 3-dimensional reconstructions can predict the size and location of stenosis.

Stenotic lesions can be divided into simple (<1 cm, granulation tissue, web-like lesion, concentric lesion, no involvement of tracheal wall) and complex stenoses (>1 cm, scarring of trachea, presence of malacia). Correct classification of the stenotic lesion is essential in determining appropriate management. The initial approach to simple lesions is endoscopic. Recurrence of simple stenosis after multiple bronchoscopic treatments often requires surgical evaluation for definitive treatment. Complex lesions require a multidisciplinary approach often resulting in surgery (Fig. 3). Endoscopic dilatation can be performed in emergent cases or as a bridge to definitive surgical correction. The preferred surgical approach depends on involvement of the larynx and extent of tracheal involvement. Laryngotracheal reconstruction is performed when subglottic tracheal lesions involve the larynx, whereas tracheal resection and reconstruction is performed when complex lesions involve only the trachea.

FIGURE 3: Treatment approach to symptomatic airway stenosis.

TM

TM is characterized as weakening of the tracheal wall leading to dynamic expiratory collapse and airway obstruction. TM is defined as >50% reduction in cross-section area of trachea during forced expiration.²² This complication is considered rare following tracheostomy placement. Ischemia from elevated tracheostomy tube cuff pressures, pooling of secretions around the cuff, and recurrent episodes of gastroesophageal reflux during mechanical ventilation may result in inflammation of the tracheal rings, also known as chondritis. Prolonged chondritis may lead to weakening of the tracheal rings that define the shape of the trachea. Such weakening can result in airway deformity, increased airway compliance, and hyperdynamic airway collapse during expiration. Unexplained difficulty in weaning from the ventilator along with repeated need for reintubation postdecannulation remain important clinical signs of TM after prolonged ventilation through a tracheostomy tube. Dyspnea on exertion, cough, recurrent pulmonary infections, difficult expectorating sputum, wheezing, hemoptysis, and syncope due to excessive coughing are common clinical symptoms of TM identified months to years after decannulation. Pulmonary function tests often reveal decreased peak expiratory flow along with notching and biphasic morphology on flow-volume loops. Dynamic expiratory chest CT reveals narrowing of airway lumen with expiratory maneuvers and is very sensitive for diagnosing TM (Fig. 4). Dynamic flexible bronchoscopy with expiratory maneuvers is the gold standard for diagnosing TM.²⁷ Patients suffering from TM can be definitively treated with posterior membrane tracheoplasty or focal tracheal resection and reconstruction. Posterior membrane tracheoplasty may result in significant improvement in quality-of-life indicators, but not in physiological outcomes.²⁸

FIGURE 4: Dynamic chest computed tomography scan for tracheomalacia diagnosis. The arrow is just pointing the trachea, which collapses during expiration.

Tracheoesophageal Fistula

Tracheoesophageal fistulas are rare complication following tracheostomy tube placement with an incidence of approximately 1%.²⁰ This complication occurs secondary to increased tracheostomy tube cuff pressures and subsequent ischemia of the tracheal mucosa. Prolonged ischemia can lead to tracheal wall necrosis, ulceration, and perforation, with subsequent erosion into the esophagus. Other possible mechanisms include erosion of the posterior tracheal wall by the distal end of the tracheal tube when it impinges posteriorly. This complication is most commonly seen in patients with concomitant nasogastric tubes in place. Surgical correction is required with primary esophageal closure, interposition of viable tissue, and tracheal repair by tracheal or laryngotracheal resection with reconstruction in the presence of stenosis or a long tracheal defect.²⁰ Patients who are not surgical candidates require a combination of tracheal stenting and esophageal stenting for palliative measures. Placement of the tracheal stent before placement of the esophageal stent is essential in this therapy, as the malleability of the esophagus can result in compression of the trachea due to excessive stent expansion.

Tracheoinnominate Artery Fistula (TIF)

TIFs are due to erosion into the innominate artery by the tracheostomy tube because of elevated pressure from the tracheostomy tube cuff or contact between the distal end of the tracheostomy tube and the innominate artery. Formation of a tracheoinnominate fistula following tracheostomy placement is a medical emergency. Innominate artery injury resulting in massive hemorrhage following tracheostomy is approximately 0.7%.²⁰ Although less frequent, other vessels involved may be the common carotid artery, inferior thyroid artery, innominate vein, or the aortic arch. Risk factors for TIF include high tracheostomy tube cuff pressures, low tracheostomy insertion, and repetitive head movements resulting in repeated contact of the tracheostomy tube and the area over the innominate artery. Physicians identifying bleeding from the tracheostomy site or within the tracheostomy stoma 48 hours or later following tracheostomy should harbor a high suspicion for TIF. Management of possible sentinel bleeding should take place in the operating room using a rigid bronchoscope to examine the stoma and anterior wall with the tracheostomy tube removed. Equipment for prompt surgical intervention should be readily available. In case of a massive bleed, the rigid bronchoscope can be used to compress the innominate artery against the sternum, while providing adequate suction, oxygenation, and ventilation. Surgical treatment of TIF involves sternotomy with ligation of affected vessel, interposition of viable tissue, and tracheal wall repair.^20,24

Tracheocutaneous Fistula (TCF)

TCFs are generated when cutaneous epithelium has healed into the tracheal epithelium. Risk factors include prolonged tracheostomy tube placement, steroid use, old age, and malnutrition. A TCF is present when the tracheostomy stoma fails to close 3 to 6 months following decannulation. Treatment includes cauterization and healing by secondary intervention, tract excision, and closure using a strap muscle flap.²⁴

CONCLUSIONS

Tracheostomy tubes are devices that are increasingly being used in patients with chronic airway diseases. The placement of tracheostomy tubes facilities liberation from mechanical ventilation, increases the ability to mobilize patients with chronic respiratory failure, and reduces the dosage of sedation. Although these devices may be essential in facilitating recovery in chronic airway disease, they are not without risk for complication. Understanding the possible early and late complications of tracheostomy placement and identifying symptoms of such complications allow physicians to provide the optimal care for patients following tracheostomy.