Keywords larynx - child - laryngostenosis
Palavras-Chave laringe - criança - laringoestenose
Introduction
Over the last 3 decades, airway reconstruction has become the treatment of choice
for subglottic stenosis (SGS) in children. Two surgical procedures are commonly used
in the management of SGS: laryngotracheoplasty (LTP), in which a cartilage graft is
used to expand the luminal diameter of the airway, and cricotracheal resection (CTR),
in which the stenosed segment is resected and an end-to-end anastomosis is performed.
LTP was first described by Evans and Todd
[1 ] in 1974, but gained popularity with Cotton in the late 70s with the widespread use
of costal cartilage grafts[2 ]. CTR is the preferred option for children with severe stenosis (Myer-Cotton grades
III and IV)[3 ].
Laryngotracheal reconstruction can be performed at a single stage, using the endotracheal
tube (ETT) as a temporary stent after surgery, or in multiple stages, with a tracheostomy
inserted (if not already in place) to safeguard the airway postoperatively. There
is evidence in the literature that the single-stage procedure is more effective, as
the ETT is used as a stent of the airway, which also helps to prevent obstructive
granulation[10 ]
[11 ].
Single-stage laryngotracheal reconstruction has become a worldwide trend, and it is
our treatment of choice for patients undergoing open surgery for SGS.
Our aim was to evaluate the success rate of single-stage LTP and CTR procedures that
were performed in pediatric patients in our hospital, to describe the characteristics
of our sample, and to compare our results to those reported in the literature.
Method
We performed a retrospective study by reviewing the medical records of patients who
underwent laryngotracheal reconstruction in the period between June 2005 and November
2009. We included all pediatric patients with laryngeal and/or proximal tracheal stenosis
who underwent a single-stage procedure.
The project was approved by the Ethics Committee of our hospital (approval #09-568).
The data were analyzed with PASW 17.0. Below, we describe the procedures in detail.
Single-stage LTP
Patients were intubated, unless a tracheostomy tube was present, in which case they
were ventilated through the tracheostomy during surgery. Patients were positioned
in cervical hyperextension, and the operative sites (anterior cervical region and
costal cartilage) were infiltrated with a 1% lidocaine solution containing epinephrine
(1:100,000).
The thorax was approached first, while minimizing the risk of contamination. The costal
graft (2 to 3 cm in length) was taken from the right submammary region, which is adjacent
to the osteocartilaginous junction, with a dissection performed close to the subperichondrial
plane.
A horizontal cervical incision was made and a subplatysmal flap was created, thus
exposing the cricoid and thyroid cartilage and the trachea. Next, an anterior midline
laryngofissure was performed. At this stage, a posterior cricoid split may be performed,
if indicated (if posterior grafting is needed). Then, if the patient underwent translaryngeal
intubation, the endotracheal tube was advanced distal to the stenotic segment. The
stenotic area was measured and the graft was fashioned in a fusiform shape ([Figure 1 ]). The perichondrial surface of the cartilage graft was positioned to face the lumen
of the airway, and the graft was sutured with 5-0 polidioxanone into the posterior
wall ([Figure 2 ]). A nasotracheal tube was introduced and left in place as an airway stent. If necessary,
another costal cartilage graft was placed anteriorly. A Penrose drain was placed and
the wound was closed in layers, including a prior tracheostomy, if present.
Figure 1. Placed on the suture costal cartilage graft and the posterior wall of the cricoid
(laryngofissure later), before the definitive positioning of the graft. Note that
the endotracheal tube, placed in the tracheostoma, below the area of stenosis.
Figure 2. Laryngofissure later viewing with costal cartilage graft sutured with PDS 5.0. Note
the wires mononylon for removal of the walls of the cricoid and trachea during surgery,
auxiliary dispensing and placing spacers which may reflect these structures.
CTR
Usually there was a tracheostomy in situ (SGS Grade 4) and the ETT was inserted through the stoma. The patient was positioned
in cervical hyperextension, and a local anesthetic solution was injected in the cervical
incision sites. An elliptical incision was made around the tracheostomy and a subplatysmal
flap was raised above the hyoid bone. An inferior subplatysmal flap was elevated down
to the sternal notch (depending on the location and the extent of the stenosis). The
airway was opened with a vertical midline incision through the cricoid cartilage and
the stenosed area was examined. The upper resection margin was defined according to
the stenosis (for example, if there was a need to remove a portion of the cricoid
cartilage, the resection was extended laterally along the lower border of the thyroid
towards the cricothyroid joint). The trachea was mobilized, keeping it as close as
possible to the tracheal wall in the subperichondrial plane. To elevate the trachea,
two 2-0 Prolene stay sutures were inserted laterally into the tracheal wall. The lower
resection margin must contain a full-sized, healthy tracheal ring. The neck was returned
to the anatomical position and a nasotracheal tube was inserted. An end-to-end anastomosis
was performed using a 2-0 PDS suture. The wound was closed in layers over a Penrose
drain.
In both LTP and CTR, the patient was referred to the Pediatric Intensive Care Unit
(PICU) after surgery, where he/she remained intubated and sedated. On the 7th postoperative
day, direct fiber optic laryngoscopy was performed, after removing the ETT for visualization
of the entire airway. If the operated area was patent, without abundant granulation
tissue, and the graft was well placed (from the LTP), the patient was reintubated
under direct visualization; sedation was reduced and the process of extubation began.
On the 7th day after extubation, a new direct laryngoscopy was made; if the airway
was patent and the patient was asymptomatic, the child was released home and scheduled
to return for outpatient follow-up. If necessary, children underwent additional procedures,
such as dilatation, CO2 laser ablation, reintubation, and/or tracheostomy.
Results
We reviewed the charts of 24 patients, aged 2 months to 17 years, who underwent LTP
or CTR for correction of subglottic and/or tracheal stenosis.
Sample characteristics
Thirteen patients (54%) were male. Of the 24 patients, 17 (71%) had no comorbidities.
Comorbidities found in the other patients included prematurity (3 patients), epilepsy
(1 patient), Fraser syndrome (1 patient) Down syndrome (1 patient), and biliary atresia
(1 patient).
The etiology of SGS was endotracheal intubation in 22 patients (91.6%) and congenital
in 2 patients (8.3%).
Among the patients in whom stenosis was caused by endotracheal intubation, the average
number of days of intubation was 11.7, ranging from 5 to 28 days. Underlying pathology
leading to intubation included the following: bronchiolitis in 7 patients (31.8%),
pneumonia in 2 patients (9%), whooping cough in 2 patients (9%), trauma in 3 patients
(13.6%), viral encephalitis in 1 patient (4.5%), sepsis in 1 patient (4.5%), disorders
related to prematurity in 2 patients (9%), meconium aspiration in 1 patient (4.5%),
tracheomalacia in 1 patient (4.5%), pulmonary tuberculosis in 1 patient (4.5%), and
postoperative complications of other surgeries in 1 patient (4.5%).
Preoperatively, the classification of SGS was the following: grade 4 SGS in 1 patient
(4%), grade 3 SGS in 16 patients (66.6%), grade 2 SGS in 4 patients (16.6%), grade
3 SGS associated with glottic stenosis in 1 patient (4%), and grade 3 SGS associated
with tracheal stenosis in 1 patient (4%).
Before definitive surgery, 18 patients (75%) required tracheostomy for respiratory
dysfunction.
Except for the insertion of the tracheostomy, LTP was the primary treatment in 19
patients (79.1%). For 3 patients (12.5%), CTR was the primary treatment, whereas carbon
dioxide laser was the initial treatment of choice for 2 patients (8.3%).
In total, 26 LTP procedures were performed (21 primary and 5 reinterventions). With
respect to the grafts, posterior grafts were placed in 9 surgeries (34.6%), anterior
grafts in 2 (7.7%), and associated grafts (anterior and posterior) were placed in
15 procedures (57.7%).
There were no reported complications during surgery. Postoperative complications included
2 cases of pneumonia, 1 internal jugular vein thrombosis, 1 graft displacement, and
1 death from septic shock. The patient who had a displaced graft underwent reinterventions
on the 14th postoperative day, 7 days after extubation from the initial surgery.
The average period of postoperative intubation was 7.7 days.
All patients had persistent fever while in the PICU. After extubation, fever ceased
in all of them. We performed a laboratory investigation for fever, but an infectious
etiology was found in only 3 cases, including 2 patients with pneumonia and 1 with
septic shock (and death).
Success rates
Among the 24 patients, 15 (62.5%) had a satisfactory airway after the initial laryngotracheal
reconstruction; 12 patients did not have stenosis and 3 had asymptomatic grade 1 SGS.
These patients were decannulated, and showed no subsequent need for reintervention.
Five patients underwent reintervention (2nd LTP, CTR, carbon dioxide laser, or balloon
dilation); all patients reestablished an adequate subglottic lumen and were decannulated
after this 2nd procedure.
Three patients underwent tracheostomy after the initial surgery because of restenosis.
A reintervention has not been undertaken yet.
One patient died postoperatively due to septic shock and was considered a failure
for the purposes of this study.
All direct laryngoscopies performed in the PICU on the 7th postoperative day showed
a patent airway, with little or no amount of granulation tissue, thus allowing the
patients to be extubated following the procedure.
The decannulation rate was 66% in patients undergoing CTR and 85.7% in patients undergoing
LTP. The overall decannulation rate was 83.3%.
Discussion
The management of laryngotracheal stenosis is a challenge for otolaryngologists, especially
in the pediatric population. They are often complex cases, in which several treatment
modalities are needed for the complete resolution of the problem. Various aspects
should be taken into account, including the type, location, and extent of the stenosis,
the degree of airway obstruction, the presence of vocal cord impairment, and the patient's
neurological status.
A variety of surgical interventions are available for the management of SGS, including
endoscopic laser with or without balloon dilatation or stent placement, balloon dilation
angioplasty, LTP with anterior, posterior, or combined costal cartilage graft, either
in single or multiple stages, and CTR. In this study, we described the results of
our experience with single-stage techniques of LTP and CTR while using the ETT as
an airway stent postoperatively in patients with subglottic and tracheal stenosis.
The etiology of the stenosis was postintubation in 91.4% of patients, which is in
agreement with previous studies reporting that 90% of patients with acquired subglottic
stenosis have a history of tracheal intubation[4 ]; 8.6% of patients had congenital stenosis, compared to an incidence of approximately
5% that was reported in the literature[5 ].
Reports from other studies have shown decannulation rates ranging from 84% to 96%
after single-stage LTP[6 ]. In cases of CTR, decannulation rates range from 91% to 95%[7 ]. In our series, the overall decannulation rate was 83.3%. When analyzed separately,
patients undergoing CTR had a decannulation rate of 66%; compared to the literature,
this lower rate was likely due to the small number of patients undergoing CTR in our
series. It is important to note that until the end of the 90s, CTR was reserved mostly
for adults[8 ]; therefore, it is a relatively new surgical procedure in the pediatric population.
When we analyzed only the LTP results, our decannulation rate was 85.7%, which is
comparable to that reported by other authors.
Until about a year ago, we did not use balloon dilatation (with an angioplasty catheter)
in the postoperative period of patients undergoing laryngotracheal reconstruction.
When we started using this device, we noticed greater ease in managing subglottic
granulation in these patients. Balloon laryngoplasty may thus increase our success
rates in laryngotracheal reconstruction, since the 4 patients in our series who presented
with restenosis would have undergone dilation after surgery, when they still had granulation
tissue, which could have altered the outcome.
All direct laryngoscopies that were performed on the 7th postoperative day showed
a satisfactory airway, which allowed patients to be extubated; this has led us to
reconsider the necessity of this procedure prior to extubation.
Postoperative fever seems to be common after airway reconstruction. A study conducted
by Schraff et al. in 2010 showed that 59% of patients who underwent single-stage LTP
had fever postoperatively; however, fever was considered significant (with positive
cultures) in only 1/3 of the cases[9 ]. In our sample, all patients had postoperative fever, which ceased after removal
of the ETT. Nevertheless, the implications and the need to investigate and treat postoperative
fever in laryngotracheal reconstructions are not yet established.
We will continue analyzing, now prospectively, data from pediatric patients undergoing
CTR and LTP in our department, and we will continue testing the balloon technique
for the treatment of restenosis after laryngotracheal reconstruction surgery.
Further studies are needed to determine the causes of therapeutic failures and to
improve the postoperative management of these children.
Conclusion
We present our series of 24 children with laryngotracheal stenosis who underwent single-stage
airway reconstruction. Our overall decannulation rate with LTP and CTR was 83.3%.
