Enlarging intratracheal tube cuff diameter: a quantitative roentgenographic study of its value in the early prediction of serious tracheal damage

Management of tracheostomy-related tracheomegaly in a patient with COVID-19 pneumonitis

Acquired tracheomegaly is a rare condition associated with pulmonary fibrosis, connective tissue disease and the use of cuffed tracheal tubes. We describe the urgent tracheal re-intubation and subsequent tracheal repair of a previously well 58-year-old man who developed tracheostomy-related tracheomegaly during prolonged mechanical ventilation for coronavirus disease 2019 pneumonitis. Urgent tracheal re-intubation was required due to a persistent cuff leak, pneumomediastinum and malposition of the tracheostomy tube. We describe the additional challenges and risks associated with airway management in patients with tracheomegaly, and discuss how even in urgent cases these can be mitigated through planning and teamwork. We present a stepwise approach to tracheal re-intubation past a large tracheal dilatation, including the use of an Aintree catheter inserted via the existing tracheal stoma for oxygenation or tracheal re-intubation if required. Computed tomography imaging was valuable in characterising the defect and developing a safe airway management strategy before starting the procedure. This report emphasises the role of planning, teamwork and the development of an appropriate airway strategy in the safe management of complex cases.

Prolonged Intubation Versus Tracheostomy in the Adult

The development of mechanical ventilators that can en sure adequate respiration for long periods of time has led to the problem of determining how to best integrate patients into the machine's airflow circuits. Tracheal tubes with inflatable cuffs efficiently connect the patient to the machine, but the tubes may be placed in one of two ways. Each option has relative advantages and disad vantages. Translaryngeal intubation (TLI) can be per formed safety and quickly and is the preferred first step in airway management. However, when TLI is needed for prolonged periods, it may damage the larynx. Tra cheostomy, on the otherhand, has potential operative and tracheal complications, but presents little risk to the larynx and may be better tolerated by the patient requir ing long-term intubation. This review provides a histor ical background of these two methods and analyzes their respective advantages and complications. Guide lines for the optimal use of TLI and tracheostomy, par ticularly in adult patients requiring long-term intuba tion, are developed by comparing the risks and benefits of these two methods.

Chest radiography in the ICU: Part 1, Evaluation of airway, enteric, and pleural tubes

OBJECTIVE

In this pictorial essay, we discuss and illustrate normal and aberrant positioning of nonvascular support and monitoring devices frequently used in critically ill patients, including endotracheal and tracheostomy tubes, chest tubes, and nasogastric and nasoenteric tubes, as well as their inherent complications.

CONCLUSION

The radiographic evaluation of the support and monitoring devices used in patients in the ICU is important because the potentially serious complications arising from their introduction and use are often not clinically apparent. Familiarity with normal and abnormal radiographic findings is critical for the detection of these complications.

ICU imaging

Chest radiography serves a crucial role in imaging of the critically ill. Its uses include diagnosis and monitoring of commonly encountered pulmonary parenchymal and pleural space abnormalities. It is also important in evaluating monitoring and support devices and associated complications. CT, another useful imaging modality in select patients, can better characterize pulmonary parenchymal and pleural space disease.

Using CT to diagnose tracheal rupture

OBJECTIVE

A retrospective study was performed to assess CT sensitivity for diagnosing tracheal rupture. Intubated cadaver tracheas were examined to assess endotracheal tube balloon overdistention and deformity and to evaluate the relationship of balloon pressures to tracheal injury.

MATERIALS AND METHODS

Neck or chest CT scans of 14 patients with tracheal rupture and 41 control trauma patients with pneumomediastinum but without tracheal injury were reviewed and compared to assess the presence and location of extrapulmonary air, whether direct visualization of tracheal wall disruption was possible, the size and shape of endotracheal tube balloon, signs of transtracheal balloon herniation in intubated patients, and the location of the extratracheal endotracheal tube. Intact and experimentally injured cadaver tracheas were used to evaluate tube balloon pressure and configuration.

RESULTS

All 14 patients with tracheal rupture had deep cervical air and pneumomediastinum. Overdistention of the tube balloon occurred in 71% (5/7) of the intubated patients, and balloon herniation occurred in 29% (2/7). Direct tracheal injury was seen in 71% (10/14) of the patients as a wall defect (n = 8) or deformity (n = 2). Overall, CT was 85% sensitive for detecting tracheal injury. Patients with tracheal injury had a significantly lower incidence of pneumothorax (p = 0.01) than did the control group. The CT appearance of balloon herniation through defects in the cadaver tracheas closely mimicked those of patients with tracheal injury. The amount of balloon pressure required to rupture the intubated trachea was extremely high and rupture was difficult to obtain.

CONCLUSION

CT can reveal tracheal injury and can be used to select trauma patients with pneumomediastinum for bronchoscopy, leading to early confirmation and treatment.

Utility of portable chest radiographs as a predictor of endotracheal tube cuff pressure

Increased endotracheal tube cuff pressure causes mucosal ischemia that can lead to necrosis, infection, and, eventually, tracheomalacia or tracheal stenosis. Endotracheally intubated patients frequently undergo portable chest radiography. In this study we explored the relationship of endotracheal tube cuff pressure and the appearance on the tracheal air columns on the portable chest radiograph. We measured the endotracheal tube cuff pressure of intensive care unit patients 124 times immediately before portable chest radiography. On 64 of these radiographs we measured the width of the tracheal air column below the tip of the endotracheal tube and at the maximal diameter of the endotracheal tube balloon. We then analyzed the relationship of cuff pressure to tracheal dilation. The results of ANOVA of tracheal dilation for three groups (safe, borderline, and unsafe cuff pressures) were significant. Large overlapping ranges existed in each group. Regression analysis confirmed a linear relationship between cuff pressure and tracheal dilation (r = 0.435, p < 0.001). Predicted tracheal expansion at 20 mm Hg was a poor screen for endotracheal tube cuff inflation safety; the sensitivity was only 56% and specificity only 71%. The differences in the capacity for tracheal distension between patients make these findings not unexpected. The portable chest radiograph is a poor screening tool for unsafe endotracheal tube cuff pressure.

Tracheobronchial lacerations after intubation and tracheostomy

BACKGROUND

Although long-term complications of intubation and tracheostomy are well documented, little has been reported on acute complications of airway access techniques.

METHODS

Fourteen patients (1 male and 13 female patients) aged 15 to 80 years presented with tracheobronchial lacerations after single-lumen intubation (n = 9), double-lumen intubation (n = 1), or tracheostomy (n = 4).

RESULTS

A left bronchial laceration after double-lumen intubation was discovered and repaired intraoperatively. A tracheal laceration after single-lumen intubation was recognized during induction of anesthesia. The remaining 12 were diagnosed within 6 to 126 hours (median, 24 hours) after injury. All patients had mediastinal and subcutaneous emphysema. At endoscopy, 12 injuries were located in the thoracic trachea and 1 in the cervical trachea. Twelve underwent primary repair through a right thoracotomy (n = 11) or left cervicotomy (n = 1), and 1 was treated conservatively. Two patients with tracheostomy injury died postoperatively. All repairs healed well but one. The latter was performed 5 days after the injury; a dehiscence occurred, but healed spontaneously.

CONCLUSIONS

We conclude that prognosis of tracheal lacerations depends both on the general health of the patient and on the rapidity of diagnosis and treatment.

Tracheal rupture after emergency intubation during cardiopulmonary resuscitation

We describe a case of tracheal rupture following an emergency intubation during cardiopulmonary resuscitation. This complication occurring during resuscitation has not apparently been reported previously. Possible causes during the management of cardiac arrest are discussed with references to previously described cases of tracheal rupture.

Tracheal dilatation followed by stenosis in Mounier-Kuhn syndrome. A case report

A patient with previously undiagnosed Mounier-Kuhn syndrome (tracheobronchomegaly) was admitted with a head injury after a fall. The trachea was intubated with an oral tracheal tube with high-volume low-pressure cuff. The intracuff pressure was within the normal safe range recommended by the manufacturer. However, the patient developed tracheal dilatation on the second day after intubation. The trachea was extubated on the 15th day, and it was noticed 48 hours later that the patient was developing a tracheal stenosis at the site of the previous dilatation. The stenosis was so severe that the patient underwent resection-anastomosis surgery of his stenotic tracheal segment 2 months after extubation. It may be preferable in patients with Mounier-Kuhn syndrome who require mechanical ventilation to intubate the trachea with an uncuffed tube and to pack the throat to decrease the chances of gas leak and inhalation.

Laryngeal injury from prolonged endotracheal intubation

This project was undertaken to develop models of acute and chronic laryngeal intubation as a format for testing a newly designed endotracheal tube. The tube has a specially created laryngeal cuff designed to reduce pressure exerted against the laryngeal soft tissues. The laryngeal foam cuff was shown to prevent the injurious sequence of mucosal ischemia, ulceration, and cartilage damage. A laryngeal foam cuff has the potential to significantly reduce laryngeal injury from prolonged endotracheal intubation. A prospective randomized clinical trial has been initiated and will be reported subsequently.

Common complications in critically ill patients

Patients in intensive care units (ICUs) are subject to many complications connected with the advanced therapy required for their serious illnesses. Complications of ventilatory support include problems associated with short-term and long-term intubation, barotrauma, gastrointestinal tract bleeding, and weaning errors. Cardiac tachyarrhythmias can arise from a patient's intrinsic cardiac disease, as well as from drug therapy itself. Hemodynamic monitoring is crucial to careful patient management, but it is associated with technical complications during insertion such as pneumothorax, as well as interpretive errors such as those caused by positive end-inspiratory pressure. Acute renal failure can develop as a result both of therapy with drugs such as aminoglycosides and hypotension of many etiologies, as well as the use of contrast media. Nosocomial infection, which is a dreaded complication in ICU patients, usually arises from sources in the urinary tract, bloodstream, or lung. Complications frequently can arise if the interactions of drugs commonly used in the ICU are not recognized. Further, the ICU patient is subject to nutritional complications, acid base problems, and psychological disturbances. This monograph deals with the frequency, etiology, and prevention of these common ICU complications.

The use of a silicone T-tube to treat tracheal stenosis in a llama

A female llama was presented at 4 days of age with severe dyspnea resulting from bilateral choanal atresia. A tracheostomy was performed before surgical treatment of the airway obstruction. Although the choanal atresia was successfully corrected, tracheal stenosis secondary to mucosal necrosis, malacia of the cartilage rings, and proliferation of intraluminal granulation tissue at and distal to the tracheal stoma developed. The affected segment of the trachea was resected and an end-to-end anastomosis was performed, but the lumen again became obstructed by granulation tissue. A silicone "T-tube" was placed in the trachea to provide a patent airway and intraluminal support. The llama has done well for 12 months with this prosthesis, and the complications that are often seen with long-term use of traditional tracheostomy tubes have not developed.

Complications of acute respiratory failure

Many complications can occur during the management of acute respiratory failure and may involve multiple organs. Some of these complications can be avoided by preventive measures. We find evaluation of serial chest roentgenograms extremely useful for the early detection of several complications (figure 4). In addition, prophylactic use of heparin to prevent pulmonary emboli, prophylactic antacid or cimetidine therapy to prevent gastric bleeding, careful monitoring of renal function, appropriate measures to reduce the incidence of colonization and nosocomial infection, and early recognition of nosocomial infections are some of the measures essential to increased survival of patients with acute respiratory failure.

A new tracheostomy tube. III. Bronchofiberoptic examination of the trachea after prolonged intubation with the NL tracheostomy tube

Recent publications show that severe damage to the trachea is still a problem with high-volume, low-pressure cuffs. The NL tracheostomy tube was used in 86 patients for 3 days to 2 months (mean 16 days). This tube has a high-volume, low-pressure cuff with automatic regulation of the cuff pressure at 3 kPa. The tube has a flexible tip. Fiberoptic examination at extubation showed minimal damage to the tracheal mucosa: 33 patients had normal mucosa and the rest had hyperaemia and/or fibrin formation. Four patients had ulcerations from suction catheters and four patients had small, superficial ulcerations produced by the tip of the tube. Of these last four patients, three had skin flaps that exerted pressure on the tube. Severe tracheal damage was prevented due to the combination of automatic regulation of cuff pressure and a flexible tip of the tube.

Results of gastric neutralization with hourly antacids and cimetidine in 320 intubated patients with respiratory failure

In a retrospective analysis massive upper gastrointestinal (GI) hemorrhage, defined as blood loss requiring more than two units of blood transfusion over a 24-hour period, occurred in 40 (9.5 percent) of 420 intubated, mechanically ventilated patients with respiratory failure, irrespective of the etiology of the respiratory failure. In a prospective study hourly antacid gastric neutralization, maintaining the gastric pH over 5, the incidence of massive gastric bleeding was reduced to 3 (1.4 percent) of 210 patients. In 110 additional patients, cimetidine, a histamine H2 receptor blocker, was used to prevent gastric acid secretion; 3 (2.7 percent) of 110 patients had massive upper GI bleeding; all three had solitary chronic pyloric ulcers. We conclude that gastric neutralization, either with hourly antacids or with cimetidine, is effective in reducing the incidence of massive gastric hemorrhage in intubated, mechanically ventilated patients during respiratory failure. We recommend the use of either in all intubated patients with respiratory failure. In addition, in 17 patients who had gastric bleeding at the time of transfer to the respiratory intensive care unit, gastric neutralization with hourly antacids in 14 patients and with cimetidine in three patients stopped the bleeding in all 17 patients within 24 to 48 hours.

Advances and controversies in the management of supraglottitis and laryngotracheobronchitis

Recent advances in pediatric airway intubation and the introduction of pharmacotherapeutic agents, active within the larynx and tracheobronchial tree, have created significant controversies in the treatment of acute obstructive inflammatory laryngeal disease. Although the etiology, pathophysiology, and clinical patterns of supraglottitis and laryngotracheobronchitis are no longer confused, decisions concerning their medical management and method of airway control remain controversial. Both inflammatory disorders are critically examined, with a reveiw of current concepts regarding the choice between endotracheal intubation and tracheotomy. Specific problems of anesthetic technique, criteria for extubation or decannulation, and the rationale for the use of corticosteroids, antibiotics, or racemic epinephrine are evaluated. If mechanical airway control is required, careful attention to initial intubation with a relatively small, cuffless polyvinyl chloride endotracheal tube and precise surgical technique when employing tracheotomy will minimize the overall morbidity. Short term intubation in acute obstructive inflammation of the larynx appears to be well tolerated. Tracheotomy is reserved for the few patients with laryngotracheobronchitis who demonstrate persistent significant subglottic edema.