Anaesthesia and tracheobronchial stenting for central airway obstruction in adults

Tracheobronchial stenting and central airway replacement

PURPOSE OF REVIEW

The present paper reviews the recent literature on the management of malignant large airway obstruction using tracheobronchial stenting and airway replacement by aortic allografts.

RECENT FINDINGS

Airway stenting is a valuable adjunct to therapeutic bronchoscopy to relieve malignant airway obstruction. Over 80% of patients with obstructing lesions who were treated by airway stenting presented immediate symptom improvement in recent series. Stenting may also function as a bridge until further curative treatment can be used. Different stent models are available; their advantages and disadvantages depend on materials and constructions; clinical experience is larger with silicon-based models than with metallic stents. An alternative strategy for the management of nonresectable primary tracheal tumors aiming to replace the central airway with an allogenic aortic allograft has been proposed. Experimental studies showed that an aortic allograft produced a respiratory conduit that shared fundamental elements of the trachea and newly formed cartilage rings were observed.

SUMMARY

Airway stenting provides efficient palliation of symptoms in patients with malignant central airway obstruction. Evidence-based studies are needed to identify patients who may have the greatest benefit from stenting. Tracheal replacement with allogenic aortic allografts is a novel technique which brings hope to the management of extensive tracheal lesions.

Perioperative management for placement of tracheobronchial stents

Tracheobronchial stenting was performed under general anesthesia, with (six patients) or without (two patients) muscle relaxant, in eight patients suffering from carcinoma. All patients had presented preoperatively with dyspnea, exhibiting Hugh-Jones grade 4 or 5. Three patients had been mechanically ventilated before the procedure. The procedure was performed under general anesthesia with flexible bronchoscopic guidance. Stent placement was performed either through an orotracheal tube (four patients) or through a transtracheal tube (two patients) in those who had no upper tracheal stenosis, while it was performed through a laryngeal mask airway in two patients with upper tracheal stenosis. During the procedure, arterial hemoglobin oxygen saturation (Sp(O(2)) decreased in all patients, despite fraction of inspired oxygen (FI(O(2)) being maintained at 1.0. Except for two patients, one of whom developed superior vena cava syndrome and one, tension pneumothorax after stent placement, there were no complications resulting from stent placement. Six patients were weaned from mechanical ventilation (0-24 days after the procedure). Two of the three patients who had been on mechanical ventilation preoperatively could not be weaned. Stent insertion is an effective treatment for tracheobronchial stenosis, but its indications in patients with malignancy who have been mechanically ventilated prior to stenting should further be evaluated.

Endobronchial tubes - a case for re-evaluation

An endobronchial tube (Macintosh-Leatherdale) was used to secure the airway for a tracheal resection and end-to-end anastomosis. This lung separation device enabled insertion of both a fibreoptic bronchoscope and a tube exchange catheter. These were required after the trachea was transected and re-anastomosis proved surgically difficult. The airway exchange catheter allowed for jet ventilation and later a tube change when an emergency occurred. Options and management issues for tracheal surgery and lung separators are discussed. A case is made for a re-evaluation of endobronchial tubes both as a useful conduit for modern airway instruments and as an alternative to small double-lumen tubes for the increasing population of obese patients weighing > 100 kg, requiring thoracic surgery.

Airway management of patients with tracheobronchial stents

The use of tracheobronchial stents for compromised large airways is increasing. We provide a case series highlighting some of the complications of airway management in patients with tracheobronchial stents in situ and propose an approach for dealing with this potentially complicated situation.

[Endoscopic treatment of central airway stenosis: five years' experience]

OBJECTIVE

To describe our experience with interventional bronchoscopy in the treatment of central airway stenosis.

PATIENTS AND METHODS

We reviewed patient records and bronchoscopic findings. Clinical data, findings from computed tomography, techniques performed, complications, and results were recorded.

RESULTS

One-hundred and thirty-six patients (90 males and 46 females) were treated. The mean (SD) age was 57 (7) years (range, 3-81). A total of 320 therapeutic interventions were performed: 145 laser treatments, 33 balloon or mechanical dilatations, 26 electrocauterizations, and 116 stent insertions. Pathogenesis varied: in 64 (47%) patients, the stenosis was caused by a tumor (48 were bronchopulmonary and 16 nonpulmonary); in 72 (53%) patients, stenosis was secondary to a nontumor-related process, of which the most common was prolonged intubation (42% of these cases). Central airway patency was achieved in 92% (59/64) of the tumor-related stenoses and 96% (69/72) of those unrelated to tumors. Improvement in dyspnea was observed in 96% of all patients. Two deaths (due to hemoptysis and to acute myocardial infarction) occurred in the first week, for a 1.4% mortality rate. The most common complications were stent migration (8%; 9/116 cases) and the formation of granulomas (9%; 11/116).

CONCLUSIONS

Interventional bronchoscopy is an effective technique to resolve life-threatening obstructions of the central airways. Dyspnea improves immediately and there is no significant morbidity or mortality.

Central Airway Obstruction

Central airway obstruction is a problem facing all medical and surgical subspecialists caring for patients with chest diseases. The incidence of this disorder appears to be rising because of the epidemic of lung cancer; however, benign causes of central airway obstruction are being seen more frequently as well. The morbidity is significant and if left untreated, death from suffocation is a frequent outcome. Management of these patients is difficult, but therapeutic and diagnostic tools are now available that are beneficial to most patients and almost all airway obstruction can be relieved expeditiously. This review examines current approaches in the workup and treatment of patients suffering from airway impairment. Although large, randomized, comparative studies are not available, data show significant improvement in patient outcomes and quality of life with treatment of central airway obstruction. Clearly, more studies assessing the relative utility of specific airway interventions and their impact on morbidity and mortality are needed. Currently, the most comprehensive approach can be offered at centers with expertise in the management of complex airway disorders and availability of all endoscopic and surgical options.

Local anaesthesia and sedation for rigid bronchoscopy for emergency relief of central airway obstruction

We report three experiences that illustrate the use of local anaesthesia for rigid bronchoscopy. All patients were acute emergencies, with life-threatening central airway problems. Instruments were inserted after the airway was anaesthetised using a technique that owes much to mid 20th Century methods for inserting endobronchial blockers. There is discussion about requirement to preserve and conserve self-ventilation and the securing of compromised central airways without the aid of neuromuscular blocking agents. Historical aspects of bronchoscopy are reviewed. Concomitant sedation reduced the unpleasantness of the experience in a way that in the past could only be dealt with by careful attention to the humanitarian elements of detail. Problems of oxygenation were ameliorated by periodically superimposing intermittent jetting with a Sanders injector fed from the oxygen pipeline. A need for developing and refining topical and other local anaesthetic techniques for rigid bronchoscopy is anticipated with the expansion of services for tracheo-bronchial stenting and lasering.