A prospective study of complications after tracheostomy for assisted ventilation

Upper airway obstruction following adult respiratory distress syndrome. An analysis of 30 survivors

To evaluate the effects of current supportive care measures for the adult respiratory distress syndrome (ARDS) upon the upper airway, we studied 30 survivors of ARDS. All patients were interviewed and examined and performed inspiratory and expiratory maximal flow-volume curves more than six months after the onset of ARDS. Three women had developed symptomatic upper airway obstruction due to laryngotracheal stenosis 4 to 12 months after discharge from the hospital. Potential etiologic factors included difficult orotracheal intubation (one) and high tracheal cuff pressures (one). The three survivors who developed laryngotracheal stenoses did not differ from the 27 survivors of ARDS without symptomatic upper airway obstruction with respect to age, duration of tracheal intubation, or maximum level of positive end-expiratory pressure. Each patient with upper airway obstruction required more than one operation for laryngotracheal reconstruction. Although corrective surgery improved airflow, two survivors of ARDS had upper airway obstruction and exertional dyspnea more than five years after the ARDS. We conclude that upper airway obstruction is an important cause of dyspnea and impairment following ARDS. Exertional dyspnea weeks to months following treatment for ARDS suggests the possibility of laryngotracheal stenosis.

Assisting ventilation in respiratory failure by negative pressure ventilation and by rocking bed

The present study was undertaken to evaluate the effectiveness of acute ventilation by rocking bed (RB) and by negative-pressure ventilator (NPV) on arterial oxygenation and carbon dioxide tension in seven patients in whom respiratory failure (PaCO2 [+/- SD], 64 +/- 4 mm Hg; PaO2, 54 +/- 10 mm Hg) was consequent on nonobstructive ventilatory impairment. The increase in SaO2 (percent above baseline, 5 percent RB and 6 percent NPV) was similar for both methods, but a greater fall in PCO2 (percentage change in PCO2, 3 percent RB; 15 percent NPV; p less than 0.05) was observed during NPV. Diaphragmatic and accessory muscle electrical activity was markedly reduced during NPV but remained unchanged or increased on RB. Asynchronous breathing was frequently observed with RB but only rarely with NPV. These preliminary results suggest that effective mechanical ventilatory support could be achieved with either RB or NPV. However, their long-term effects as compared with those of positive-pressure ventilation remain to be explored.

Glottic and tracheal stenosis in spinal cord injured patients

Between 1965 and 1985, 47 cases of glottic and/or tracheal stenosis were diagnosed at the Rocky Mountain Regional Spinal Cord Injury System. A retrospective review of medical records identified associated injuries, pulmonary and other medical complications in this patient population. Radiographic and endoscopic reviews utilised a grading system to classify the severity of stenosis. The clinical symptoms of stenosis were multiple, including dysphonia, aspiration, dysphagia, odynophagia, dyspnea and excessive secretions. The wide spectrum of treatment modalities included endoscopy with excision and/or dilation, general medical management, steroids, radiation therapy, intubation, stent insertion and surgical repair of the stenotic area. Outcome status was reviewed and suggestions provided for the early diagnosis and treatment of this potentially life-threatening condition.

Upper airway sequelae in burn patients requiring endotracheal intubation or tracheostomy

During a period of 11 1/2 months, 41 of 217 adult burn patients admitted to the U.S. Army Institute of Surgical Research Burn Center required endotracheal intubation or tracheostomy for management of the airway and/or ventilatory assistance. Permanent upper airway sequelae were recorded and related to presence of inhalation injury, duration of tube placement, cuff pressure, and pulmonary compliance. An "inhalation injury scoring system" based upon history, physical examination, bronchoscopic findings, and abnormalities at 133xenon lung scan correlated well with postinjury alteration in compliance and subsequent sequelae. Significant inhalation injury was found in 35 patients. Seventeen of the study patients survived (Group I) and 24 patients expired (Group II). Group I patients were screened for permanent airway sequelae by fiberoptic bronchoscopy, xeroradiograms, and spirometry undertaken an average of 11 weeks after extubation or decannulation. Four patients developed tracheal stenosis and five patients had significant tracheal scar granuloma formation. Sequelae were generally more frequent and more severe after tracheostomy than after translaryngeal intubation, and duration of tube placement and presence of a tracheal stoma were the most important etiological factors in permanent damage. For initial respiratory support, we favor the use of translaryngeal (nasotracheal) tubes for periods up to 3 weeks. Fiberoptic bronchoscopic examination is the most reliable follow-up method for detecting anatomic damage in such patients. Spirometry can be used as a noninvasive screening test and xeroradiograms are helpful in assessing the degree of tracheal stenosis.

Cricothyroidotomy for long-term tracheal access. A prospective analysis of morbidity and mortality in 76 patients

Cricothyroidotomy for long-term tracheal access was prospectively studied in 76 critically ill patients. Thirty patients (39%) survived and 46 (61%) died. Mean duration of follow-up computed in all survivors was 8.5 months. Postmortem examination of the airway was performed in 85% of the nonsurvivors. Five patients (7%) had major complications including one death, subglottic stenosis in two adolescent patients, reversible subglottic granulation with partial obstruction in one patient, and tracheomalacia in one patient. Minor complications occurred in 23 (30%) survivors. Eleven (28%) of the nonsurvivors examined post mortem had airway pathology, including ulceration, hemorrhage and abscess at the stoma or cuff site, subglottic erosion, and mucosal separation. There were no significant differences in any of the parameters studied between the group with and the group without airway pathology. The morbidity and mortality of cricothyroidotomy in adults are similar to that reported for tracheostomy. However, cricothyroidotomy should be avoided in children and adolescents because of the risk of subglottic stenosis.

Variable tracheal stenosis related to body position

We demonstrated a variable extrathoracic tracheal stenosis which developed after technically adequate tracheostomy and was worsened by changes in body position. When the patient's arms were above his head, minimal airway diameter was reduced 31 percent, and maximal inspiratory flow rate 37 percent below values measured with arms down, but expiratory flow rates were preserved. Tracheostomy may disrupt the integrity of tracheal support and allow airway collapse under circumstances of increased extratracheal or decreased intratracheal pressure.

Long-term tracheal intubation practice in the United Kingdom

A questionnaire was circulated to members of the Intensive Care Society and hospitals with more than 120 acute beds in the United Kingdom. The object was to determine the usage of the various types of cuffs on tracheal tubes and the practice of long-term tracheal intubation in contrast to tracheostomy. One hundred and fifty two replies were received (a 55% response rate). The majority of units favoured the high volume cuff for long term ventilation (61% for tracheal tubes and 69.2% for tracheostomy tubes). The cuffs were mainly inflated to 'no-leak' ventilation and pressure was not measured. The majority of units changed from tracheal tubes to tracheostomy after about one week but, for children, a longer period of tracheal intubation is employed. The results are discussed.

Complications of acute respiratory failure

Acute respiratory failure is frequently fatal. Attempts to decrease mortality must include attention to pulmonary and extrapulmonary complications. Pulmonary complications include pulmonary emboli, barotrauma, fibrosis, and pneumonia. Swan-Ganz catheters, tracheal intubation, and mechanical ventilation can also result in pulmonary complications. Extra-pulmonary complications such as gastrointestinal hemorrhage, renal failure, infection, and thrombocytopenia may increase mortality. Early diagnosis, aggressive treatment, and prophylaxis of complications should increase survival.

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.

Complications and consequences of endotracheal intubation and tracheotomy. A prospective study of 150 critically ill adult patients

A prospective study of the complications and consequences of translaryngeal endotracheal intubation and tracheotomy was conducted on 150 critically ill adult patients. Adverse consequences occurred in 62 percent of all endotracheal intubations and in 66 percent of all tracheotomies during placement and use of the artificial airways. The most frequent problems during endotracheal intubation were excessive cuff pressure requirements (19 percent), self-extubation (13 percent) and inability to seal the airway (11 percent). Patient discomfort and difficulty in suctioning tracheobronchial secretions were very uncommon. Problems with tracheotomy included stomal infection (36 percent), stomal hemorrhage (36 percent), excessive cuff pressure requirements (23 percent) and subcutaneous emphysema or pneumomediastinum (13 percent). Complications of tracheotomy were judged to be more severe than those of endotracheal intubation. Follow-up studies of survivors revealed a high prevalence of tracheal stenosis after tracheotomy (65 percent) and significantly less after endotracheal intubation (19 percent)(p < 0.01). Thirty-nine of 41 (95 percent) patients with endotracheal intubation and 20 of 22 (91 percent) patients with tracheotomy had laryngotracheal injury at autopsy. Ulcers on the posterior aspect of the true vocal cords were found at autopsy in 51 percent of the patients who died after endotracheal intubation. There was no significant relationship between the duration of endotracheal intubation or tracheotomy and the over-all amount of laryngotracheal injury at autopsy, although patients with prolonged endotracheal intubation followed by tracheotomy had more laryngeal injury at autopsy (P = 0.06) and more frequent tracheal stenosis (P = 0.05) than patients with short-term endotracheal intubation followed by tracheotomy. Adverse effects of both endotracheal intubation and tracheotomy are common. The value of tracheotomy when an artificial airway is required for periods as long as three weeks is not supported by data obtained in this study.

Healing of lesions caused by cuffed tracheostomy tubes and their late sequelae; a follow-up study

The healing of tracheostomy and cuff-induced tracheal injury was followed up in 48 tracheostomized patients (44 men and 4 women). The patients were studied by means of tracheoscopy, fluoroscopy and tracheography, with a positive contrast medium. At extubation, tracheoscopy revealed 12 mild, 23 moderate and 13 severe injuries at the cuff level. Three months after extubation, the stoma had closed in 89% of the patients studied. In 85% of the patients, the side wall of the stoma was found to have collapsed inwards and in 71% scars were observed at the cuff level. No significant changes took place after the follow-up study at 3 months. At tracheography it was found that narrowing of the tracheal diameter at the stomal level was of only mild or moderate degree (i.e. 0-33%). There was not a single instance of severe stenosis. At the cuff level, a slight inward collapse of the side wall was observed in one patient, and in all the other patients the lumen was normal. Fluoroscopy did not reveal severe tracheomalacia in any patient. Increased mobility of the stomal scar, especially in connection with coughing was seen in some patients. One tracheo-innominate artery erosion and one bleeding granulation tissue at the stoma were confirmed during follow-up. Surgical trauma to the trachea at the stoma seems to be a more potent cause of subsequent narrowing of the trachea than the cuff. Even though severe injuries may also heal with few sequelae, the use of tracheostomy tubes with large, low-pressure cuffs, which have been shown to cause less damage to the trachea, is indicated.

Prevention of complications from prolonged tracheal intubation

Eight commercially available soft cuff endotracheal tubes were studied to determine the relationship between inflation pressure distention of the cuff. Although the balloon cuff may be easily distensible in open air, when confined within the trachea small increments in the inflation volume may produce high pressures. This means that continuous external control of cuff pressure is required to prevent ischemia of the tracheal wall. Major tracheal complications in a busy ICU were examined before and after the introduction of a controlled pressure tube. Control of intratracheal cuff pressures decreased major tracheal complications tenfold and eliminated complications specifically related to the cuff.