Keywords
bronchial disease - tracheal injury - stent - anesthesia - benign lesion
Introduction
Tracheal rupture or major tracheal injury is a rare condition mostly seen in cases
of head and neck injury. Certain procedures also carry the risk of iatrogenic injury
(intubation, tracheostomy, bronchoscopy, stent placement, esophagectomy, and others).
Tracheal rupture is defined as complete circumferential injury of the trachea. Tears
are longitudinal injuries of the trachea, both seen in orotracheal intubation especially
in the emergency setting. This appears to be the most common cause.[1]
[2]
Orotracheal intubation is a routine procedure that nevertheless carries the potential
for complications. Despite the large number of intubations performed every day, these
complications fortunately are rare. They include throat pain, laryngitis, glottis
edema, and mucosal ulceration, to laryngeal or tracheal stenosis, necrosis of the
tracheal wall, fistulas, aspiration, esophageal intubation, bronchial intubation,
atelectasis, and tracheal rupture. Some procedure-related risk factors have also been
described which are as follows: multiple forced attempts, inexperience of the health
professional, over inflation of the cuff, incorrect position of the tip of the tube,
repositioning the tube without deflation of the cuff, inappropriate size of the tube,
significant cough, and movements of the head and neck while the patient is intubated.[3]
[4] Constitutional risk factors as congenital tracheal abnormalities, weakness of the
pars membranous of the trachea, chronic obstructive pulmonary disease, diseases that
alter the position of the trachea (mediastinal collections, lymph nodes, or tumors),
chronic use of steroids, advanced age have been discussed.[5] Most case reports refer to female patients above the age of 50 years. Chen et al.
performed a literature review and defined an at-risk population that included women
over 50 years of age who required intubation with double-lumen tubes and/or excessive
pressure of the tube cuff.
The first case series was published in 1995.[6] Post-intubational tracheal injury is a very rare disease and the suspected incidence
is approximately 1/20,000 endotracheal intubations.[7] More recently published cases and case series showed 0.05 to 0.15 cases per thousand
intubation performed.[8]
Tracheal injury is suspected when signs of subcutaneous emphysema, chest pain, pneumothorax,
or hemoptysis are present. In a clinical setting computer tomography is usually performed
to rule out pulmonary embolism and other causes of acute chest pain. Diagnosis is
confirmed by bronchoscopy which shows the size and location of tracheal injury. Bronchoscopy
is also essential to plan further treatment options and helps to guide endo-tracheal
tubes. The treatment of choice has traditionally been urgent surgical repair, though
a recent review of the literature advocates conservative treatment.[2] In a meta-analysis including 181 patients, 61% were treated with tracheal surgery
whereas 39% underwent a conservative approach with prolonged tracheal intubation and
ventilation. All patients diagnosed with intra-operatively were treated surgically.
Overall mortality was approximately 22%. Some series have demonstrated an extremely
high mortality rate, especially in critically ill patients with tracheal injury and
following intraoperative surgical repair. Because of the high intra- and postoperative
mortality, the conservative approach was favored. Marquette et al demonstrated a case
of tracheal rupture with spontaneous healing as soon as positive-pressure ventilation
was not applied.[9]
A group from Taiwan[10] published a treatment algorithm based on the review of several case reports in 2004
and a previously designed approach by Jougon et al.[11] The authors proposed an algorithm for the treatment of post intubation tracheobronchial
rupture and suggested surgical repair for patients with immediate symptoms. Surgery
is decided when the length of the tear is longer than 4 cm, otherwise a conservative
management is favored.[12]
As novel treatment option endotracheal stent placement has been described in a few
case reports.[13] This option of a non-surgical approach with an endo-bronchial interventional technique
is simple to perform and gives reasonable results without the complications of major
thoracic surgery. Only few case reports are available and in most reviews and published
algorithms, this technique has not been even mentioned. We present a case of successful
stent placement and healing of an iatrogenic tracheal injury.
Case Report
A 64-year-old woman underwent elective surgery for total knee endoprothesis at an
orthopedic surgical department. General anesthesia was routinely performed and the
patient was intubated with a normal 8 mm endotracheal tube. The patient had no underlying
pulmonary or cardiac disease, no history of smoking and normal routine blood parameters.
The elective surgery was performed without complications. She received apixaban for
antithrombotic prophylaxis and was transferred to the normal ward. Six hours after
extubation, the patient developed chest pain and dyspnea. ECG and Chest X-ray reports
were found to be normal. D-dimer was slightly elevated so chest CT for exclusion of
pulmonary embolism was performed. Oxygenation and hemodynamic were normal. Chest CT
showed no signs of embolism, no consolidations, no pneumothorax. CT scan revealed
pneumo-mediastinum and tracheal injury ([Fig. 1]). The patient was then referred to our pulmonary department for bronchoscopic evaluation
and further treatment. She was stable without signs of cardiopulmonary impairment
but was monitored during transfer and waiting time for the endoscopic procedure. As
the tracheal tear had already been diagnosed before, the patient was intubated by
a rigid tracheoscope in general anesthesia. The tracheal tear started at the middle
part of the trachea and continued till 1cm above the carina ([Fig. 2a]). The length of the tear was approximately 5cm. The bronchial system below the tracheal
injury was normal without signs of other injuries.
Fig. 1 Pneumomediastinum and tracheal rupture after routine endobronchial intubation. CT-scans
with coronary and sagittal reconstruction.
Fig. 2 (A, B) Tracheal injury in the distal tracheal part with a 4 cm long tracheal tear and bronchoscopic
imaging after stent placement (ALVEOLUS tracheal stent).
Stent placement was performed under visual control by rigid and flexible bronchoscope.
Intubation for bronchoscopies was done routinely with a rigid bronchoscope (Storz,
Germany) and jet ventilation at our institution. A covered self-expandable metal stent
was placed (Alveolus Air stent, United States) under additional fluoroscopic control.
Stent position could be controlled by the aid of a small flexible bronchoscope through
the working channel of the positioning system. It was possible to place the stent
over the complete fissure and injury area. After deployment of the endotracheal stent,
the fissure was completely closed and the outer diameter made a complete wall adhesion
to the tracheal wall. ([Fig. 3])
Fig. 3 Chest X-ray and CT-scan after successful endotracheal stent placement.
The patient was shifted to our standard care ward for overnight surveillance and did
not develop any further complications. The next day, Routine bronchoscopic control
showed an ideal position of the stent. A CT scan for evaluation of pneumo-mediastinum
and pneumothorax was performed and revealed complete absorption of air and a complete
closure of the tracheal tear. ([Fig. 2b]) The patient could be dismissed and was readmitted 6 weeks later for bronchoscopic
stent removal. The trachea had healed completely and did not show any granulation
tissue or other stent complications.
Discussion
Tracheobronchial stents have long been used in the management of airway obstruction
in both malignant and benign diseases[14] with excellent short-term symptomatic relief. Severe long-term complications as
granulation tissue, stent migration, infection, and chronic cough shorten the use
in benign conditions[15]
[16]
[17]
Postintubational tracheal injury is a very rare condition and we therefore do not
have adequate prospective studies to evaluate its incidence. Consensus on the best
treatment options has not yet been agreed upon. Early surgery has been favored for
large tears with progression of symptoms and need for mechanical ventilation. Treatment
of tracheal tears was recommended by major surgery especially in cases of previous
thoracic surgery intra-operatively because of easy accession to the lesion.[18] Some case series and a meta-analysis performed by Minambres et al in 2009 suggested
that there is more evidence for supporting conservative management by observation,
intubation, and cuffing by the endotracheal tube and mechanical ventilation with restricted
inspiratory pressure.[2]
[19]
Most available guidelines are based on algorithms for surgical versus conservative
treatment. Supported by some case reports and a proposed algorithm by Yopp et al[13] tracheal stenting was a feasible therapeutic option. In our case, it was much easier
to treat the patient's injury by stenting as the tear was below the first third of
the trachea and did not exceed the main carina. A surgical approach was dismissed
because of its potential risks.
We believe that tracheal stenting is a useful therapy for large tracheal injury and
a valid alternative in patients precluded from surgical reconstruction with a comparatively
high rate of perioperative morbidity and mortality. Stent placement is a simple and
secure procedure that supports an early healing of the tears. Stent explantation should
be considered six weeks after placement as the risk for occurrence of granulation
tissue rises after 3 months. Iatrogenic tracheobronchial tears have typically been
handled conservatively in patients with small tears (< 2 cm in length) or those without
progressive worsening mediastinal or subcutaneous emphysema.[20] Larger tears (> 4cm) were traditionally managed surgically. For all lesions between
2 and 4 cm in length a variety of approaches have been reported by different authors
and the applied technique was decided individually and depending on the availability
of different therapeutic options.
The specific surgical approach depends on the location of tracheal injury: lesions
found in the proximal two thirds of the trachea are approached by a cervical collar
incision, more distal ones by a right anterior thoracotomy.[20]
[21]
This treatment algorithm can be adapted, in both situations, the early treatment of
the tear by stenting provides increment of mediastinal or subcutaneous emphysema and
probably the occurrence of mediastinitis ([Fig. 4]).[20] To date, the question as to which technique can prevent mediastinitis cannot be
sufficiently answered from the available literature and data. The exact incidence
rate of mediastinitis is not known and can only be estimated. There are several reports
of mediastinitis complicating esophageal rupture, fistulae and stents but no cases
of mediastinitis complicating airway stents. Antibiotic treatment seems to be indicated
in any procedure with open access of the mediastinal tissue to the normal bacterial
colonization of the tracheobronchial system.
Fig. 4 Algorithm for management of iatrogenic tracheal injury adapted from Yopp et al 2007[13] and Fan et al 2004.[10]
Stent indication should be limited to injuries with the possibility of complete closure
by the device and sufficient distance from the larynx for patient's comfort and avoiding
complication. A combined stenting of the distal trachea and the main stem bronchi
is possible with Y-stents. There is no difference in the occurrence of stent complications.
Limitations to this therapeutic approach are known stent complications including stent
migration, mucostasis, halitosis and granulation tissue development. With the use
of completely covered (newer) tracheal stents or silicon stents, these problems decrease
as has been reported in patients with other indications for tracheobronchial stents.
In case of early stent-failure, a progression to any other treatment option is possible
(see the proposed treatment algorithm).
Conclusion
This case report shows the feasibility of endoscopic stent placement in the emergency
treatment of tracheal injuries. In our case, an iatrogenic tracheal tear was treated
by endotracheal stent placement which was left in place for six weeks. There were
no complications to report. Stenting is a successful treatment option for tracheal
tears and has no severe complications.
