Tracheal Stenosis as a Complication of Tracheos tomy

Transcription

1 Tracheal Stenosis as a Complication of Tracheos tomy D. A. Murphy, M.D., L. D. MacLean, M.D., and A. R. C. Dobell, M.D. T racheal stenosis is a rare complication of tracheostomy. As Colles [5] wrote in 1886: A reliable percentage of cases of tracheotomy with or without stenosis is, owing to the conflicting reports and differences of opinion, hardly possible. At the time, he stated that the literature contained some 50 cases, of which he had seen 6. Many of these, of course, were high tracheostomies, a surgical technique abandoned following Jackson s condemnation of it in 1921 [9] because of the high incidence of laryngeal stenosis. Jackson had never seen stenosis following a tracheostomy below the second tracheal ring, but he was constantly caring for chronic laryngeal stenosis following high tracheostomies performed by others. Since 1921 few reports of tracheal stenosis have appeared; only in the past few years, with the widespread use of cuffed tracheostomy tubes for controlled and assisted ventilation, have sporadic reports appeared in the French, Belgian, and American literature. The largest series that we have found was referred to by Aboulker et al. [l]: stenosis occurred in 22 of 600 patients undergoing tracheostomy with controlled ventilation at the Centre de RCanimation Neurorespiratoire de l h8pital Claude Bernard; 150 further cases had subclinical tracheal narrowing. In contrast are series such as that of Dugan and Samson [6], with 1 stenosis in 461 tracheostomies and this responding to tracheal dilatation; of Head [S], with 2 stenoses in 462 operations; or of Atkins [2], with 1 stenosis in 526 operations. The occurrence of 4 cases of severe tracheal stenosis in the course of a single year on our Surgical Service was therefore viewed with alarm. These cases all followed standard tracheostomies with insertion of a cuffed metal tube for assisted ventilation. From the Department of Surgery, The Royal Victoria Hospital and McGill University, Montreal 2, P.Q., Canada. Accepted for publication Aug. 26, THE ANNALS OF THORACIC SURGERY

2 Tracheal Stenosis with Tracheostonzy CASE REPOH TS CASE 1 The first case was that of a 22-year-old female who had an elective tracheostomy after mitral valve replacement. A No. 8 cuffed metal tube was inserted through a circular opening in the anterior tracheal wall. The tube was in place for 12 days. Twenty-three days following decannulation, a second cardiac operation was required. The anesthetist could not pass the smallest endotracheal tube through her stenosed trachea, and tracheostomy was required before the operation could begin. She succumbed shortly after operation with the second tracheostomy still in place. At postmortem examination, a tight fibrous stricture was seen at the level of the previous tracheostomy stoma. CASE 2 The second patient was a 31-year-old man who suffered a cerebral embolus during mitral valve replacement. A No. 8 cuffed metal tracheostomy tube was inserted through a circular defect in the anterior tracheal wall. The cannula was in place for 24 days. Twelve days after decannulation, signs of airway obstruction were apparent and a new tracheostomy was made. It was maintained for the remainder of his life which was spent in a convalescent hospital. The trachea was examined after his death, and severe stenosis was noted at the original tracheostomy stoma site. CASE 3 The third case was an 18-year-old girl who required a second aortic valve replacement after subacute bacterial endocarditis led to partial tearing out of the first. A cuffed No. 8 tube was inserted through an ti-shaped incision in the second and third tracheal rings. The tube was in place for 17 days; 29 days after its removal the signs of upper airway obstruction were recognized. A second tracheostomy was performed just beneath the stricture, and she underwent a series of tracheal dilatations. This permitted decannulation, and she was discharged home. She later developed pneumonia with Diplococcus pneumoniae septicemia, from which she died. A third tracheostomy tube was inserted following her terminal emergency admission, and this was in place for the last 6 days of her life. CASE 4 The fourth patient was a 41-year-old woman who had an elective tracheostomy with insertion of a cuffed metal tube through a circular defect in the anterior tracheal wall after mitral valve replacement. The cannula was removed after 6 days, and 22 days later stridor appeared. Tracheography showed a stricture of the trachea at the level of the tracheostomy stoma. Lateral films showed a sinus tract extending out into the soft tissues of the neck where the anterior tracheal wall had not yet healed. The stenosis was visualized at tracheoscopy, and its fibrous nature was confirmed without evidence of granuloma. A second tracheostomy was performed at the site of stenosis. This tracheostomy tube remained in place for a month, at which time tracheoplasty was performed. The trachea was widely exposed and incised above and below the tracheostomy orifice. Flaps were developed and swung across as a Z-plasty to widen the tracheal diameter. Tracheoscopy was done again two weeks later and no significant stenosis was found, although there was some narrowing at the operative site. Table 1 summarizes the pertinent facts in these clinical cases. All Stelloses resulted from tracheostomies with insertion of a cuffed metal VOL. 2, NO. I, JAN.,

3 MURPHY, MACLEAN, AND DOBELL TABLE 1. CLINICAL TRACHEAL STENOSIS AFTER TRACHEOSTOMY Interval from Duration Removal to Tracheostomy Tracheostomy Recognition of I ncisiona (days) Stenosis (days) case 1 Circular Case 2 Circular Case 3 H-shaped Case 4 Circular 6 22 aa cuffed metal tube was inserted in all cases. tube. The cuffs on these tubes were designed to be placed about anesthetic endotracheal tubes, the inflatable cuff being 36 mm. in length. The stenosis occurred in all of the cases at the tracheal orifice and not in the trachea caudad to the orifice. Tracheostomies were performed in 3 instances by excision of a circle of anterior tracheal wall and in 1 case by raising lateral flaps of trachea with an H-shaped incision. This latter type of tracheal opening is no longer employed as it increases the tracheal ring deformity at the stoma. ANIMAL EXPERIMENTS Experiments were carried out in 14 dogs to evaluate certain factors possibly contributing to stenosis. The Endotrucheal Balloon. Was endotracheal cuff pressure producing stenosis? An endotracheal-tube cuff was pulled over a lw segment of hardened polyvinyl tubing measuring 1/211 in diameter. This tube was passed into the trachea of 3 dogs by way of the mouth, and the small tube necessary to inflate the cuff was passed out through a needle hole in the anterior tracheal wall (Fig. 1). The balloon was reinflated FIG. 1. Experimental evaluation of role of endotracheal CUB pressure in producing tracheal stenosis. A hardened polyvinyl tube 1/211 in diameter covered with an endotracheal cufl was passed orally into the trachea, the smaller tube for cufl inflation passing through a midline puncture wound. No stenosis was produced by this technique despite ten days of inflation. 46 THE ANNALS OF THORACIC SURGERY

4 Tracheal Stenosis with Tracheostorny daily for ten days to insure maximal inflation. The apparatus was then removed, and the animals were bronchoscoped weekly and sacrificed after four weeks. When the cuff was removed, mucosal reddening was seen bronchoscopically. This had almost disappeared a week later, and there was no residual evidence of endotracheal trauma when the animals were sacrificed. No stenosis occurred. Following the development of our first clinical case of tracheal stenosis, attention was immediately directed to the endotracheal cuff. It seemed reasonable that pressure necrosis of the tracheal mucosa might have resulted which in the presence of infection would lead to chondritis of the tracheal rings, chondromalacia, and eventually fibrotic stricture. All personnel were instructed to deflate the cuffs hourly and to inflate them cautiously after reattaching the respirator. The cuff was to be inflated slowly to the point where air leak was abolished. The three subsequent clinical cases developed tracheal stenosis after we had emphasized these points. We have seen severe tracheitis with fragmentation of tracheal rings in patients dying after prolonged respirator treatment. There is no doubt that severe damage may result from the endotracheal cuff, at least in the presence of infection. It was not, however, a cause of the stenoses reported herein. Chondromalacia. Was stenosis due to softening of tracheal rings by trauma and infection? To evaluate this possibility, two tracheal rings were completely excised subperichondrially in 4 animals (Fig. 2). The dogs were bronchoscoped weekly and sacrificed after three weeks. Immediately after the resection, it was noticed that no serious tracheal deformity had been produced. There was only minimal retraction of the unsupported trachea on inspiration. No narrowing was seen at bronchoscopy nor at postmortem examination. There was some FIG. 2. Subperichondrial resection of two tracheal rings, done in order to mimic tracheomalacia. No stenosis resulted. VOL. 2, NO. I, JAN.,

5 MURPHY, MACLEAN, AND DOBELL longitudinal retraction so that the final distance between intact tracheal rings was reduced by about one-third. Deformity at the Stoma. In 4 dogs the trachea was opened with a modified H-type incision, and a large, cuffed metal cannula was inserted. The cuff was of the type in clinical use when the patients included in this report were operated upon and was longer than we now consider desirable. It was so placed on the cannulas that it blew up within the tracheal stoma and the soft tissues of the neck and held apart the tracheal rings deformed by the incision (Fig. 3). The cuffs were reinflated daily for seven days. The animals were then bronchoscoped weekly and sacrificed after three weeks. Tracheal stenosis developed in 3 of the 4 dogs (Fig. 4). In 1 it was moderate, and in 2 it was severe, with reduction to one-half the FIG. 3. Tracheal deformity was produced experimentally by inflating a long (36 mm.) endotracheal cufl in the tracheostomy orifice. Tracheal stenosis developed in 3 of 4 dogs after this procedure. FIG. 4. An example of the tracheal stenosis experimentally produced by the technique shown in Figure 3. The tracheal rings at the tracheostomy stoma are flat, having lost their normal curvature. 48 THE ANNALS OF THORACIC SURGERY

6 Tracheal Stenosis with Tracheostomy normal lumen size. One animal had clinical stridor. The tracheal rings had lost their normal curvature anteriorly. Instead of bowing in, the lateral tracheal walls were straight, and the separation anteriorly was filled in by fibrous tissue. The tracheal mucosa showed squamous metaplasia at the point of stricture. The same experiment was repeated in 3 more dogs, save that a circle of anterior tracheal wall was resected to fashion the tracheal stoma. One of the 3 animals developed severe stenosis. DISCUSSION A deformed tracheal stoma maintained and intensified by a balloon cuff passing out the stoma into the soft tissues of the neck can produce tracheal stenosis. We believe this was the major cause of the clinical stenoses reported herein. Two factors can be considered: the cuff and the incision. The cuff should be a short one, fitting snugly around the enclosed cannula so that it cannot slide back toward its stem. The cuff formerly in use at this hospital measured 36 mm. in length and was actually designed for use on the oral endotracheal tubes used by anesthetists. The difference between it and the one in current use (18 mm. long) is shown in Figure 5. Regarding the incision, deformity can occur with a circular opening as well as with an incision not involving resection of tracheal wall. The circular opening has been made with a scalpel and actually more closely resembles a square, since linear cuts are generally made horizontally and vertically. Less deformity would result from the use of a circular tracheotome. Such an instrument [7] makes a clean circular FIG. 5. Endotracheal cuffs passed over metal tracheostomy tubes. On the right is shown a cuff designed to go over an endotracheal tube. This is twice the length of the proper tracheostomy tube cufl shown on the left. VOL. 2, NO. I, JAN.,

7 MURPHY, MACLEAN, AND DOBELL defect which is less likely to be distorted. Flaring out of the lateral tracheal walls is a situation particularly to be avoided. Two of our patients received treatment of their tracheal stenosis beyond simple bypass of the obstruction by a fresh tracheostomy. The young woman (Case 3) received steroids without obvious benefit. We were, however, more satisfied with the tracheal dilatations carried out by the hospital s department of otolaryngology. These were performed at about weekly intervals, and the dilatation achieved the previous week was maintained at the next dilatation. Thus there was steady widening of the stenotic area to a size of 32 French, when the tracheostomy tube could be removed. Few cases in the literature have been successfully managed in this way, a notable example of a good result being the patient treated by Chance and his associates [41 in whom stenosis developed 57 years after tracheostomy. A preferred method of treatment is tracheal resection with end-toend anastomosis. Several such operations have been reported successful, for example, that of van Wien [lo] who resected 2.5 cm. of trachea, or those of Binet and Aboulker [3], or Witz et al. [ll]. It had been our intention to carry out this procedure in Case 4. After exposure of the trachea, a tracheoplasty seemed to be a simpler means of relieving the stenosis. A Z-plasty type of procedure was employed. SUMMARY Four cases of severe tracheal stenosis following tracheostomy with insertion of a cuffed metal tube for respirator treatment are reported. The stenosis in all patients was at the tracheostomy site. The cuff on the metal tubes was 36 mm. long and probably extended out of the tracheostomy orifice into the soft tissues of the neck. Inflation of cuffed tubes of this type in animals led to tracheal stenosis. A shorter (18 mm.) cuff has been employed for the past twelve months and no further stenoses have resulted. REFERENCES 1. Aboulker, P., Lissac, J., and Saint-Paul, 0. Respiratory accidents due to laryngo-tracheal stricture post tracheostomy. Acta Chir. Belg. 59: 553, Atkins, J. P. Analysis of 526 cases of tracheostomy. Laryngoscope 70:1672, Binet, J.-P., and Aboulker, P. Un cas de stenose trachcale apres trachkotomie: RCsection-suture de la trachce gucrison. Mem. Acad. Chir. (Paris) 87:39, Chance, D. P., Devine, K. D., and Schmidt, H. W. Cicatricial tracheal stenosis after tracheostomy: Report of a case. Proc. Mayo Clin. 29:388, Colles, C. J. On stenosis of the trachea after tracheotomy for croup and diphtheria. Ann. Surg. 3:499, Dugan, D. J., and Samson, P. C. Tracheostomy: Present day indications and technics. Amer. J. Surg. 106:290, THE ANNALS OF THORACIC SURGERY

8 Tracheal Stenosis with Tracheostomy 7. Hammond, G. L., and MacLean, L. D. Tracheotome tracheostomy. Surg. Gynec. Obstet. 118:1325, Head, J. M. Tracheostomy in the management of respiratory problems. New Eng. J. Med. 264:587, Jackson, C. High tracheostomy and other errors, the chief causes of chronic laryngeal stenosis. Surg. Gynec. 0 bstet. 32: 392, Van Wien, A., De Clercq, F., Van Eyck, M., and Reinhold, H. Tracheal stenosis after tracheostomy. Acta Chir. Belg. 60:85, Witz, J. P., Greiner, G., Reys, P., and Lang, S. Low stenosis of the thoracic trachea post tracheotomy. Mem. Acad. Chir. (Paris) 86: 123, VOL. 2, NO. I, JAN.,