Radiological evaluation of post-tracheostomy lesions

Tracheal stenosis in infants and young children

Eight cases of intra-thoracic tracheal stenosis presenting to the ENT department at the Hospital for Sick Children, Great Ormond Street, over the past 10 years are reported. The varied aetiology and presentation of these cases is discussed and the frequency of associated cardio-pulmonary anomalies emphasized. Difficulties in diagnosis and investigation are outlined, in addition to an overview of current management. While the overall outlook for many of these children remains poor there is reason to believe that a balance of conservative management and surgical reconstruction in selected cases will result in improved survival figures.

Reconstructive surgery for obstructing lesions of the intrathoracic trachea in infants and small children

This is a report of ten infants and small children with congenital obstructive lesions of the distal trachea and main bronchi. Four were successfully resected. One with a distal segment stenosis required tracheal resection at age 6 wk, another with stenosis of the distal half of the trachea at age 18 mo, and 2 (1 with distal stenosis and 1 with tracheal hamartoma) at age 4 yr. All 4 are presently free of symptoms and their anastomoses have grown without stricture. A child with coil-spring mucosal stenosis of the left main bronchus developed an excellent airway following bronchoscopic removal of the folds, and a baby with tracheomalacia was successfully treated with a rib splint on a segment of distal tracheomalacia, but she died later of associated cyanotic congenital heart disease. Four babies died with airway obstruction in the newborn period. Two with critical distal stenoses died before tracheal reconstruction could be performed. Two died following emergency resections in which all of the congenital stenosis could not be removed. In both, stenotic trachea remained despite operation. All of these infants had complete cartilage rings the entire length of the trachea. Congenital lesions of the distal trachea may become suddenly life-threatening at birth or during the onset of a respiratory infection. An abrupt or insidious onset of airway symptoms requires an expeditious diagnostic evaluation to define the tracheobronchial anatomy, and the operating team has to be prepared for emergency tracheal reconstruction.

[Pathomorphology of intensive care treatment (author's transl)]

The pathologic consequences of intensive care treatment are manifested locally and generally. Local disturbances due to intensive care therapy are as follows: blood vessel injury, thromboembolism caused by catheterization, tracheal stenosis following tracheostomy and, most important, sepsis. The more general pathologic results of intensive care treatment are essentially brought about by shock. Shock-kidney plays a subordinate role today because it is a reversible state of renal insufficiency. In contrast, shock-lung leads to death in about 50% of the cases. The pathohistologic features of the initial stages are microthrombosis, perivascular edema and endothelial damage. These three characteristics are already apparent before hospital admission and institution of treatment. It is not yet clear to what extent the therapy augments the pathologic changes or leads to clinically manifested symptoms.

Tracheography with the experimental contrast agent tantalum

Before the use of tantalum powder, positive contrast studies of the trachea were performed with a viscous oily iodine suspension. Iodine in suspension is not very radiopaque, and is moderately toxic. The oily portion of the contrast media is viscous and tends to obstruct the airways. In patients with compromised airway diameters such as those with tracheal stenosis, a positive contrast study was often considered too dangerous to perform. At this time, operability and the type of surgery anticipated was based on radiologic studies with poor anatomical detail. Tantalum is a safe contrast agent which is exceptionally radiodense and nontoxic. A small amount of tantalum dust coats the airway, giving excellent detail without compromising the airway diameter. Radiographic studies demonstrate excellent anatomical detail and are obtained with little patient discomfort. There have been no complicaions. Thirty-two patients with suspected tracheal stenosis have been studied by a protocol utilizing powdered tantalum as the contrast agent. Seven were normal. Varying degrees of tracheal stenosis were found in 18 patients. Five had only tracheomalacia, eight patients had a combination of both stenosis and malaria. Tracheomalacia was discovered in three patients in whom it was not suspected clinically. Consequently we are performing cine examinations on all patients with suspected high airway obstruction. Certain technical details are crucial to the proper performance of this procedure. These, as well as the characteristic findings in each disease category, are presented.

Obstructive lesions of the trachea

Over 100 patients with obstructing lesions of the trachea have undergone resection and end-to-end reconstruction in the past decade. Eighty-four of these had lesions of inflammatory origin and 16 were neoplastic. Their symptoms were primarily airway obstruction. Postintubation lesions of the trachea occur most commonly at the level of inflatable cuffs used to obtain a seal during ventilatory therapy and next most commonly at the level of tracheal stomas in similar patients. Their etiology is chiefly cicatrization following deep ulceration due to pressure necrosis at one of the two sites. Additional lesions may also occur at other levels. The most common primary neoplasm of the trachea was squamous cell carcinoma; the second most common was adenoid cystic carcinoma. Autopsy studies indicated that approximately one-half of the trachea might be resected and primary reconstruction done if certain principles of anatomic mobilization were followed, dependent on the level of the lesion and its extent. Upper tracheal lesions are approached clinically anteriorly through a cervicomediastinal approach with or without division of the upper sternum. In all but extreme cases direct approximation can be done. On a rare occasion, a laryngeal release procedure will provide additional mobility. Tumors of the lower half of the trachea are approached through a high transthoracic incision with appropriate hilar mobilization in addition to cervical flexion for devolvement of the cervical trachea into the mediastinum. In the first 100 consecutive cases, 73 of the 84 patients with benign stricture had a good or excellent result on morphologic and clinical grounds. Four were satisfactory, four represented failures or poor results and there were three deaths. Only one-third of 29 patients with primary neoplasms of the trachea were reconstructable when first seen. Others were suitable for radiation treatment only, no treatment or laryngotrachiectomy. Eleven patients underwent end-to-end reconstruction. There was one operative death, one late recurrence and the other nine are living without known disease from 1 to 11 years postoperatively.

Reconstruction of the trachea. Experience in 100 consecutive cases

Grillo, H. C. (1973).Thorax, 28, 667-679. Reconstruction of the trachea. Experience in 100 consecutive cases. Anatomic mobilization of the trachea permits resection of one-half or more with primary anastomosis. An anterior approach by a cervical or cervicomediastinal route utilizes cervical flexion to devolve the larynx and tracheal mobilization with preservation of the lateral blood supply. The transthoracic route is employed for lower tracheal lesions.

Over 100 tracheal resections have been done using these methods of direct reconstruction. Eighty-four patients suffered from benign strictures, 79 resulting from intubation injuries. Eleven primary tracheal tumours and five secondary tumours are included. The majority of lesions following intubation occurred at the level of the cuff. It was possible to repair 78 of the 84 stenotic lesions through a cervical or cervicomediastinal approach. Seventy-three of the 84 patients with inflammatory lesions obtained an excellent or good functional and anatomic result. Nine of 11 patients with primary neoplasms who underwent reconstruction are alive and without known disease. There were five early postoperative deaths in these 100 consecutive patients who underwent tracheal reconstruction.