Subglottic stenosis

Subglottic Stenosis in Children: Preliminary Experience from a Tertiary Care Hospital

INTRODUCTION

This retrospective study describes our experience in the evaluation and management of infants with subglottic stenosis.

MATERIALS AND METHODS

The study included 10 patients aged between 1 wk and 18 months with 6 cases having congenital subglottic stenosis and 4 cases having acquired subglottic stenosis.

RESULTS

6 patients had grade I, 3 patients had grade II, and 1 patient had grade III subglottic stenosis. Tracheostomy was required in 4 patients at the time of presentation. 7 patients were treated successfully with Bougie dilation followed by topical application of mitomycin, whereas 1 patient who failed to serial dilation needed open reconstructive procedure. Laser excision of the anterior subglottic web was performed in one patient. Another patient with underlying cerebral palsy could not be operated upon and was managed with tracheostomy.

CONCLUSION

Subglottic stenosis may be effectively man-aged with endoscopic surgical techniques, although the number of such sittings required varies with the type and severity of stenosis. Open surgical procedures need to be individualised as per the needs of the patient only after all the other endoscopic possibilities have been exhausted.

Subglottic stenosis associated with transesophageal echocardiography

Transesophageal echocardiography (TEE) is used extensively to assess cardiac function and anatomical relationships in both adults and children. Although considered a noninvasive procedure, TEE in infants and small children may result in airway complications. A patient who developed subglottic stenosis after the use of TEE during a cardiac procedure is reported.

Tracheostomy in children: there is a place for acceptable risk

BACKGROUND

Tracheostomy in children remains controversial regarding the risk of complications.

METHODS

Forty-six trauma patients (35 male and 11 female, mean age = 6.8 years) were admitted to the intensive care unit between 1987 and 1991 with severe head injury plus coma. Tracheostomy was performed with standard technique after 5.9 days (range, 2-12 days) of intubation.

RESULTS

There were no deaths from tracheostomy, but six deaths resulted from severe head injury. One child was discharged with tracheostomy. The 39 survivors remained with tracheostomy 16.14 days (range, 4-71 days) in the intensive care unit. After cannula removal, 31 remained asymptomatic; 8 had respiratory distress: 2 were normal, 5 had endoscopic treatment for subglottic granulomas/stenosis from intubation, and 1 had tracheomalacia from tracheostomy. In 1997, the 18 patients located for follow-up were asymptomatic. At endoscopy, 8 were normal, 9 had subglottal granulomas from intubation, and 1 had 20% tracheal stenosis from tracheostomy.

CONCLUSION

Most complications after tracheostomy result from intubation. Tracheostomy has an acceptable risk in children with severe head injury who need prolonged ventilatory support.

Modifications of airway reconstruction in children

We review our treatment experience of subglottic stenosis in 66 children. Sixty-one of these children required some form of airway expansion using cartilage grafts. Eight children had grade I (Cotton classification), 15 grade II, 28 grade III, and 15 grade IV stenosis. All patients with grade I and II lesions were decannulated. Ninety-three percent of grade III patients and 67% of grade IV patients were also ultimately decannulated. Laryngotracheal reconstruction with costal cartilage grafting has become widely accepted for treatment of severe laryngotracheal stenosis. Several modifications of this technique have been employed to treat our patients. Recently, we have used a modified single-stage technique with an endotracheal tube stent, externally secured for 1 week, to avoid postoperative intensive care unit admission for sedation and/or paralysis, and its related complications. Posterior graft design and placement without sutures was also performed in 20 cases. A two-surgeon technique that involves a simultaneous endoscopic control of incision of the stenotic area was employed. These modifications will be described in detail.

Endoscopically Introduced Expandable Stents in Laryngotracheal Stenosis: The Jury is Still Out

A new technique using endoscopically introduced, expandable stents for the management of upper airway stenosis is presented. Evaluation of this technique in the canine model forms the basis of this pilot study. Stenosis was surgically induced in a controlled fashion by resection of cartilage from the anterior cricoid arch and tracheal wall to reduce the airway diameter by approximately 50%. A period of 8 weeks was allowed for complete healing and maturation of the surgical stenosis. This was followed by endoscopic introduction of expandable titanium-mesh stents. The stents were then balloon-inflated to dilate the stenotic region. Airway patency was assessed clinically, radiologically, and endoscopically, before expansion and at 4 and 8 weeks after expansion. This assessment was followed by euthanasia of the animals and gross examination of the expanded stenotic segments. In general, the stents were well tolerated with adequate expansion of the airway. In some instances granulation tissue formation was noted around the stents. This was less pronounced when stents coated with Tecoflex (Advanced Surgical Intervention Co., San Clemente, Calif.) were used. This is probably because of their “inert” nature, which induces less tissue reaction. A literature review of the subject is presented. The significance of this endoscopic modality for management of upper airway stenosis is discussed, and the indications, alternatives, potential pitfalls, and complications are depicted.

Tracheostomy in children--the Red Cross War Memorial Children's Hospital experience 1980-1985

During the 6 years (1980-1985) at The Red Cross Children's Hospital 293 children required a tracheostomy during treatment of a variety of disorders. Of these children 44% were under 1 year of age. Indications are discussed of which the commonest was LTB. Of the 3500 children seen with laryngotracheobronchitis (LTB) 4.6% had a tracheostomy--28% of those requiring airway intervention. Overall 67% of the children were decannulated within 10 weeks and 92% within a year. For 56% one or more further procedures prior to decannulation were required, including 34 children who required a laryngotracheoplasty. Obstructing stomal granulation tissue had to be removed from 51 children and suprastomal collapse was a cause of decannulation failure in 52 children. Use of an expiratory valve as an aid to decannulation is discussed. Five children died of tracheostomy airway complications and 25 children of a medical disorder. One complication, laryngeal incompetence, was particularly associated with herpetic laryngeal ulceration. Staphylococcus aureus and Hemophilus influenzae were the main organisms cultured in the early weeks, with Pseudomonas and Streptococcus species predominating later.

The anterior cricoid split in puppies

The acute and long-term effects of the anterior cricoid split on the subglottis of puppies intubated from 7 to 14 days are documented. The anterior cricoid split acutely increased the intralumenal cricoid surface area in puppies with intubation-induced airway injury. An intense inflammatory response with mucosal ulceration and granulation tissue is elicited by 14 days of intubation by using the canine model of induced subglottic stenosis developed by Supance et al. [19]. When animals intubated for 14 days underwent an anterior cricoid split on day 7, the airway appears essentially normal by day 14. The split cricoid cartilage maintained a 'U' configuration following the procedure. The region of deficient cartilage anteriorly is bridged by fibrous tissue with normal epithelium lining the lumenal surface. Splitting the cricoid cartilage anteriorly increased the intralumenal area and no long term complications resulted from the procedure. The mechanisms by which the anterior cricoid split expands the airway intralumenal area while maintaining airway support have been reviewed.

Anterior cricoid split: a "simple" surgical procedure and a potentially complicated care problem

The anterior cricoid split (ACS) has been described as an alternative to tracheotomy in management of the premature infant who develops upper airway compromise after extubation. Sixteen patients at the Children's Hospital National Medical Center (CHNMC) and ten patients at four other hospitals had the ACS operation. For the patients at the CHNMC, average gestational age was 29 weeks, birth weight was 1,264 g, and length of time intubated was 6.2 weeks. Overall success in achieving extubation after the ACS was 69% at the CHNMC and 40% for the group of other hospitals. However, a success rate in achieving extubation after ACS was 75% for both the CHNMC and the group of other hospitals in patients who had become stable enough to have been previously discharged from a neonatal intensive care unit. Problems encountered following the ACS include malposition of tip of the endotracheal tube, increased need for assisted ventilation, myocardial infarction, subcutaneous emphysema, and unexplained inability to ventilate. Analysis of results suggests that the ACS is a valuable operative procedure that can avoid need for tracheotomy in infants with adequate pulmonary function who have narrowing within the airway at the subglottic level. Postoperative care may be problematic and the infant having had the ACS is best managed by an experienced team of experts who are familiar with care of the infant with respiratory insufficiency.

Endotracheal tube movement in the preterm neonate: oral versus nasal intubation

Endotracheal intubation of a preterm infant cadaver was performed both orally and nasally to assess the relative movement of the endotracheal tube with changes in head position. For each method of intubation, anteroposterior radiographs were obtained with the head in neutral, flexed, extended, and laterally rotated positions. The results indicate slightly increased movement of the nasotracheal tube with flexion and rotation, and markedly increased movement with extension. The possible relationship between tube movement and the development of subglottic stenosis is discussed.

Contemporary surgical management of laryngeal stenosis in children

Both congenital and acquired subglottic stenoses are common problems in pediatric otolaryngology, but their treatment remains controversial. While conservative therapy, consisting of dilation and observation, may be appropriate for congenital stenoses, open surgical procedures are generally needed to correct acquired stenoses. Two major reconstructive methods, costal cartilage grafting and laryngotracheoplasty, are currently in use. The anterior cricoid split is a specialized procedure used for extubation in the neonate. Aggressive surgical intervention has produced consistently good results and early decannulation. Laryngeal growth has not been affected adversely by these external operations.

Ten-year review of pediatric tracheotomy

One hundred sixty-four consecutive tracheotomies are reviewed over the 10-year period 1972-1981. Early in the series acute inflammatory airway obstruction was the major indication for tracheotomy, being 60% of cases in the first 3 years. In the last 3 years this fell to approximately 15%. After 1975 nasotracheal intubation replaced tracheotomy for acute epiglottis. More recently it has become the treatment of choice for acute laryngotracheobronchitis. Tracheotomy prior to reconstructive surgery for major craniofacial abnormalities is becoming more frequent. Acquired subglottic stenosis is not a problem in our hospital despite the use of long-term nasotracheal intubation in premature infants, and no tracheotomies were performed for this indication. There were few major complications. Decannulation difficulties were due to obstruction by stomal granulation tissue or displaced flap of anterior tracheal wall. There was no case of hemorrhage, no posttracheotomy stenosis, and no death was attributable to tracheotomy. These results demonstrate that in a major pediatric hospital tracheotomy is a relatively safe and effective procedure with minimal morbidity.

Antibiotics and steroids in the treatment of acquired subglottic stenosis. A canine model study

The efficacy of a combination of systemic antibiotics and a steroid in the prevention of acquired subglottic stenosis (ASGS) was evaluated employing a previously developed canine animal model. Thirty-five healthy, postweanling mongrel puppies aged 5 weeks were each intubated for 14 days with an uncuffed polyvinyl endotracheal tube. Twenty puppies received intramuscular dexamethasone (1 mg) daily, and procaine penicillin (100,000 IU) and dihydrostreptomycin (0.125 g) in two divided doses on the day of intubation and each day thereafter until the completion of the study. The remaining 15 puppies served as a control group and received no medical therapy. Animals from both groups were killed at 5, 7, 12, 15, 20, 30, and 56 days following intubation. Comparative examinations of the laryngotracheal complexes of treated and control dogs showed that there was no significant difference between the two groups in the ultimate degree of ASGS attained, as determined by intraluminal cross-sectional area analysis, or in the extent of the lesion as documented by gross and microscopic histology. This investigation showed that the specific systemic combination of two antibiotics and a steroid used in the study was not efficacious in the prevention of ASGS in a canine animal model; for this reason we question the benefit of analogous medical regimens employed to prevent ASGS in infants and children who require long-term endotracheal intubation.