Keywords tracheoinnominate artery fistula - tracheostomy - sentinel bleed
Introduction
Tracheoinnominate artery fistula (TIF) is an unusual, life-threatening complication
of both open surgical tracheostomy and percutaneous dilatational tracheostomy, and
its incidence varies from 0.3 to 4.5%.[1 ]
[2 ] The peak incidence of TIF is within the first 3 weeks of tracheostomy tube placement,
with most cases reported within the first 18 months.[3 ] While the majority of cases of TIF have been reported in adult patients, a few cases
of TIF in pediatric patients have been noted in recent years.[4 ]
[5 ] However, a recent study looking at complications related to tracheostomy in children
did not find TIF and major bleeding to be an important complication of tracheostomy.[6 ] The increase in the number of infants and children requiring long-term tracheostomy
support for the management of chronic respiratory failure in the United States raises
the possibility that the incidence of TIF may increase.[7 ] We report a case of a pediatric patient, with a long-standing tracheostomy tube,
who developed a TIF and associated hemorrhagic sequelae.
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Case Report
The patient was a 13-year-old female patient with arthrogryposis multiplex congenita,
static encephalopathy, spastic quadriplegia, profound intellectual disability of unknown
etiology, complex myoclonic seizures, disuse osteoporosis with multiple prior bone
fractures, gastrostomy tube dependence, and chronic respiratory failure with tracheostomy
and mechanical ventilation dependency. The patient's tracheostomy was placed during
early infancy and no major complications related to tracheostomy were noted except
for occasional episodes of bacterial tracheitis. The patient had never experienced
prior episodes of bleeding from the tracheostomy.
On the day of her presentation, the patient's home care nurse reported bright red
blood from her tracheostomy and mouth after tracheal suctioning, which was atypical.
After emergency department evaluation, the patient immediately underwent laryngoscopy,
bronchoscopy, and broncheoalveolar lavage by a combined team of pediatric otolaryngologists
and pulmonologists. The procedures revealed bloody crust in the tracheostomy tube
and distal trachea but no active source of bleeding. With these findings, the patient
was diagnosed with a pulmonary hemorrhage and suspected pneumonia and was admitted
to the pediatric intensive care unit (PICU) for treatment with intravenous steroids
and antibiotics.
Further diagnostic evaluation was undertaken within 48 hours of admission, including
repeat bedside bronchoscopy, computerized tomographic angiography (CTA) of the chest,
and echocardiography. The bronchoscopy revealed areas of hypertrophic tissue on the
posterior wall of the trachea and mild irritation of the tracheal mucosa, normal appearing
bronchi, and no evidence of bleeding in the tracheobronchial tree. Echocardiography
was unremarkable. Chest CTA did not show evidence of pulmonary arteriovenous malformations
but did demonstrate the innominate artery to be in close proximity to the anterior
surface of the trachea near the tip of the tracheostomy tube ([Fig. 1 ]). The patient's hemoglobin level was 7.5 g/dL, decreased from a value of 12.5 g/dL
a few weeks prior to admission, but as she was otherwise asymptomatic and stable for
the next several days, she was discharged home.
Fig. 1 The CT angiography showing relation of innominate artery to tracheostomy tube (arrow).
Innominate artery dividing just anterior to trachea and lower end of tracheostomy
tube.
Three days following the discharge, the patient presented to the emergency department
with another episode of tracheal bleeding. Therapy with intravenous steroids and antibiotics
were resumed. Her tracheostomy tube was downsized from a 5.5-mm internal diameter
and 46-mm length tube to a 5.0-mm internal diameter and 44-mm length tube because
of the tracheal mucosal irritation noted during the prior bronchoscopy. Aggressive
pulmonary hygiene therapy and tracheal suctioning were withheld. A brief episode of
tracheal bleeding during a tracheostomy tube change led to a second airway bronchoscopy.
It revealed mucous mixed with blood in the trachea and distal bronchi with no apparent
bleeding source. The patient was readmitted to the PICU for further management. Her
hemoglobin at that time had improved to 9 g/dL. Coagulation parameters and platelet
count were normal. Interventional radiology consultation was obtained, but no catheter-directed
therapies were recommended based upon the results of the prior CTA. After 48 hours
of stability, the patient was discharged to home.
Four days following the second discharge to home, the patient presented to an outside
hospital following a sudden onset of large volume bleeding from the tracheostomy.
Total blood loss by the time of PICU admission following transport was estimated to
be 300 to 400 mL. Over the next hour, massive hemorrhage from the trachea continued
resulting in hemorrhagic shock. Multiple blood products were administered. Pediatric
cardiothoracic and general surgeons were consulted. Interventions included manipulation
of the tracheostomy tube, inflation of the tracheostomy tube cuff to compress the
area by repositioning of the tracheal tube, and direct arterial compression using
a finger. Despite these interventions, she continued to bleed massively and progressed
to cardiac arrest. She underwent emergent sternotomy with chest exploration, ligation
of the innominate artery, and closure of the tracheal stoma. Ultimately, the patient
had recurrence of cardiac arrest and spontaneous circulation could not be re-established.
Discussion
TIF is a rare but devastating complication of tracheostomy tube placement. While reports
of TIF have primarily involved adults with recent tracheostomy tube placement, reports
like ours involving pediatric patients with long-standing tracheostomy tubes are emerging.[4 ]
[5 ] The expanding population of infants and children with tracheostomy tubes increases
the possibility for TIF development. Therefore, clinicians who care for children with
tracheostomy tubes must be familiar with this potential complication.
The innominate artery is the most commonly involved vessel in tracheal fistula formation
after tracheostomy placement, but the common carotid artery, the innominate vein,
the inferior thyroid artery, the internal mammary artery, and the aortic arch may
also be involved.[8 ] The formation of a TIF is multifactorial and involves destruction of the anterior
wall of the trachea and the posterior wall of the innominate artery. Mechanical issues
that lead to fistula formation include high tracheostomy tube cuff pressures, a malpositioned
tracheostomy tube tip, a high innominate artery, and a low-lying tracheostomy tube.
Tracheostomy cuff pressures above 20 mm of mercury may result in pressure necrosis
of the mucosa of the anterior tracheal wall.[9 ]
[10 ]
[11 ] Steroid use, stoma infection, malnutrition, excessive head movement, and spasticity
also can exacerbate injury to the tracheal wall lying against the tip of the tracheostomy
tube.[12 ]
[13 ] Our patient did not have a cuffed tracheostomy tube. However, she had other risk
factors including spasticity and arching of the neck that may have led to long-term
repetitive injury to the anterior wall of the trachea, multiple episodes of bacterial
tracheitis and pneumonia, and multiple courses of steroid treatment.
Approximately 50% of cases of TIF have minor, bright-red preliminary (sentinel) bleeding
before massive delayed hemorrhage. Sentinel bleeding is self-limited but recurrent
in nature and is aggravated by coughing or aspiration. Ten mL or more of blood from
an established tracheostomy should be considered diagnostic of a TIF and treated accordingly
until proven otherwise.[8 ] Often, the sentinel bleed will spontaneously stop. Easy controllability of bleeding
does not rule out the diagnosis of TIF. The mortality rate approaches 100% without
urgent surgery as opposed to 20% with early recognition and proper management.[14 ]
[15 ]
If TIF is a possibility, bronchoscopy should be considered carefully as it can destabilize
a clot that is preventing massive hemorrhage. Although bronchoscopy is unlikely to
identify the fistula opening per se, it may exclude other pathology such as irritation,
infection, erosion, or ulceration of tracheal mucosa. In addition, rigid bronchoscopy
can clear the tracheobronchial tree of aspirated blood.[8 ]
[16 ]
[17 ] If bronchoscopy confirms that the main bronchi are free of blood, then immediate
intervention is not required. However, further investigation to confirm other causes
of bleeding, such as coagulopathy and bronchopneumonia, is vital. Other causes of
hemorrhage must be excluded before a sentinel bleed associated with TIF can be confirmed.[18 ]
The small size of the fistula presents a major diagnostic challenge when using CTA
for diagnosis. CTA may identify tracheal compression by an artery, intimate contact
of an artery with the trachea, spilling of intravenous contrast into the airway, arterial
erosion, and mediastinal infiltration, but actual visualization of a fistula with
CTA has not been very successful. Thus, in the absence of active bleeding when sentinel
bleeding had stopped, a CTA is not confirmative.[19 ]
[20 ] In the correct clinical setting where other causes of bleeding have been excluded,
CTA evidence of close contact between an artery and the trachea at the site of the
lower end of the tracheostomy tube may be sufficient evidence to diagnose a TIF such
that, even with small sentinel bleeding, stomal exploration should follow.
If massive hemorrhage occurs, the goal is temporary hemostasis to allow transfer to
the operating room. Overinflating the tracheostomy tube cuff with the tracheostomy
tube in a partially withdrawn position to directly occlude the bleeding vessel has
been successful in 85% of cases. An oral endotracheal tube should be passed immediately
with its cuff distal to the tracheal stoma to prevent blood from entering the airways.
If bleeding is not controlled, the tracheostomy tube should be completely removed
after oral endotracheal tube placement. In addition, digital pressure with the index
finger should be applied on the innominate artery against the posterior surface of
the sternum after dissection in the pretracheal fascia (Utley's maneuver). This maneuver
is successful 90% of the time, and should be continued during transfer to the operating
room, where surgical ligation of the innominate artery and fistula is the life-saving
procedure.[8 ]
[21 ]
Conclusion
TIF is a devastating and potentially fatal complication of tracheostomy tube placement.
It may occur in long-term tracheostomy-dependent children, as in our case, but most
cases described in the literature are reported following recent tracheostomy placement.
There should be a high index of suspicion after any episode of bleeding from a tracheostomy
in excess of 10 mL, as this may represent a sentinel bleed. Bronchoscopy and CTA might
not confirm the diagnosis, but any close contact between any major artery or vein
and the anterior tracheal wall on CTA in the appropriate clinical settings may be
adequate to warrant urgent surgical intervention.
