| Tracheoinnominate Fistula | |
|---|---|
| Other names | Tracheal-innominate artery fistula |
 | |
| Depicts the anatomical relationships in the formation of a fistula between the trachea and the innominate artery. | |
| Specialty | Vascular surgery |
Tracheoinnominate fistula (TIAF or TIF) is an abnormal connection (fistula) between the innominate artery (brachiocephalic trunk or brachiocephalic artery) and the trachea. A TIF is a rare but life-threatening iatrogenic injury, usually the sequela of a tracheotomy. [1]
Symptoms include hemoptysis, and/or massive hemorrhage which result from the formation of a fistula between the trachea and the brachiocephalic artery. [1] The primary threat is respiratory compromise leading to dyspnea and cyanosis. Patients can later present with hypovolemic shock which include symptoms of tachycardia, cyanosis, cold and clammy skin, dizziness, confusion, and fatigue. [2] [3] Patients may also develop sepsis. [2] [3]
The innominate artery usually crosses the trachea at the ninth cartilage ring, however this can vary from the sixth to the thirteenth cartilage ring in patients. [1] A TIF runs between the trachea and the innominate artery. Through this connection blood from within the artery may pass into the trachea or alternatively air from within the trachea may cross into the artery.
TIF is a late complication of a tracheotomy and is associated with prolonged endotracheal intubation, as a result of cuff over inflation or a poorly positioned tracheostomy tube. [1] [4] Over inflation of the cuff causes the tracheostomy tube to erode into the posterior aspect of the innominate artery leading to the formation of a fistula. [2] The pathogenesis of an TIF by the aforementioned method is pressure necrosis by tracheostomy tube on the tracheal wall. [2] An TIF can also occur due to innominate artery injury as a result of an bronchoscopy. [5]
Patients whose tracheotomies are placed beneath the third tracheal ring cartilage and patients with innominate arteries crossing higher on the trachea have an increased risk of developing an TIF. [2] Other factors contributing to the development of TIF include steroids, which weaken the endotracheal mucosa, episodes of hypotension in which the pressure in the tracheostomy tube exceeds that of the endotracheal mucosa, and radiation therapy. [2]
An endotracheal tumor can mimic a TIF and present with massive bleeding during a rigid bronchoscopy. [5]
Two-thirds of TIF occurs within three weeks of a tracheotomy. [2] A TIF should be on the top of the differential diagnosis in patients with a tracheostomy followed by bleeding. [2] [3] Most effective diagnostic tool is a rigid bronchoscopy, although this may be unnecessary as a massive arterial hemorrhage from the tracheostomy likely indicates the formation of an TIF. [1] [2] However, a rigid brochoscopy can clear the tracheobronchial tree of aspirated blood and may be used to terminate blood flow. [3]
Only 35% of TIF patients exhibit the pathognomonic warning signs which include sentinel bleeding, a small bleed from the tracheostomy in the preceding the TIF, and pulsations of the tracheostomy tube that coincides with the heartbeat. [2] [6]
To prevent an TIF, intubation time should be limited to less than 2 weeks and proper techniques should be used when performing tracheotomies. [1] The occurrence of an TIF can be reduced by using more flexible and blunt tracheostomy tubes and insuring that the tubes are properly aligned in the patients. [1] Placing the tracheostomy between the second and third tracheal rings can minimize the risk of an TIF. [1] Repetitive head movements, especially, hyperextension of the neck should be avoided as since this movement results in contact between the innominate artery and the underside of the tube. [4] [2]
The formation of a TIF is a medical emergency and requires immediate intervention. [4] Blood volume control, management of the hemorrhage, and adequate oxygenation should be ensured in these patients. [3] In a majority of TIF cases (85%), hyperinflation of the tracheostomy cuff will control the bleeding, while the patient is prepared for surgery. [1] [2] However, if this fails the tracheostomy cuff must be removed, and the patient must be intubated from above. Next, pressure from the index finger can be applied on the bleeding site from within the tracheostomy to control the bleeding. [2] In addition, the "Utley Maneuver", which involves digital compression of the artery against the posterior wall of the manubrium of the sternum following a right infraclavicular incision, may be used to urgently control the bleeding [1] [2] When the bleeding is controlled the patient should be immediately transferred on the operating room. [1] [2]
A sternal saw and a rigid bronchoscopy is used during the operation. During the operation, a median sternotomy is performed in order to expose and ligate the involved artery above and below the fistula. Division of the thymus and superior retraction of the innominate vein exposes the innominate artery. [5] The innominate artery should be debrided to healthy tissue and closed with a monofilament suture. [5] Next, the damaged segments of the trachea and the artery should be excised followed by reconstruction with a primary end to end anastomosis of the trachea. Innominate artery ligation leaves the carotid and subclavian circulations intact. [4] Pulsatile back-bleeding from distal innominate artery stump should be checked to insure collateral circulation. [5] In patients with poor pulsatile back-bleeding, an aorta-axillary artery bypass graft can be considered in patients with severe occlusion of the left common carotid artery, severe atherosclerosis, and brain ischemic or hemorrhagic insults. [6] In addition, an autologous vein bypass between the aorta and the carotid artery or the opposite carotid artery and the subclavian artery may be performed to restore normal circulation. [2] The interposition of viable tissue facilitates tracheal wall repair. Thus, vascularized tissues such as the thymus, strap muscles, the sternocleidomastoid, or the pectoralis major muscle should be interposed between tracheal defect and the vessel stumps to prevent bleeding, seal the mediastinum, fill dead space, cover major vital structures, provide a blood supply and venous drainage, and increase the concentration of antibiotics. [2] [5]
Innominate artery ligation has a 10% risk of neurological deficit. [4]
TIF is a rare condition with a .7% frequency, and an mortality rate approaching 100% without surgical intervention. [4] Immediate diagnosis and intervention of an TIF is critical for the surgical intervention success. [4] [2] 25-30% of TIF patients who reach the operating room survive. [1] [2] Recently, the incidence of TIF may have declined due to advances in tracheostomy tube technology and the introduction of the bedside percutaneous dilatational tracheostomy (PDT). [6]
The trachea, also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals with lungs. The trachea extends from the larynx and branches into the two primary bronchi. At the top of the trachea the cricoid cartilage attaches it to the larynx. The trachea is formed by a number of horseshoe-shaped rings, joined together vertically by overlying ligaments, and by the trachealis muscle at their ends. The epiglottis closes the opening to the larynx during swallowing.
Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic tube into the trachea (windpipe) to maintain an open airway or to serve as a conduit through which to administer certain drugs. It is frequently performed in critically injured, ill, or anesthetized patients to facilitate ventilation of the lungs, including mechanical ventilation, and to prevent the possibility of asphyxiation or airway obstruction.
The brachiocephalic artery,brachiocephalic trunk, or innominate artery is an artery of the mediastinum that supplies blood to the right arm, head, and neck.
Mechanical ventilation or assisted ventilation is the medical term for using a machine called a ventilator to fully or partially provide artificial ventilation. Mechanical ventilation helps move air into and out of the lungs, with the main goal of helping the delivery of oxygen and removal of carbon dioxide. Mechanical ventilation is used for many reasons, including to protect the airway due to mechanical or neurologic cause, to ensure adequate oxygenation, or to remove excess carbon dioxide from the lungs. Various healthcare providers are involved with the use of mechanical ventilation and people who require ventilators are typically monitored in an intensive care unit.
Tracheotomy, or tracheostomy, is a surgical airway management procedure which consists of making an incision (cut) on the anterior aspect (front) of the neck and opening a direct airway through an incision in the trachea (windpipe). The resulting stoma (hole) can serve independently as an airway or as a site for a tracheal tube or tracheostomy tube to be inserted; this tube allows a person to breathe without the use of the nose or mouth.
In human anatomy, the subclavian arteries are paired major arteries of the upper thorax, below the clavicle. They receive blood from the aortic arch. The left subclavian artery supplies blood to the left arm and the right subclavian artery supplies blood to the right arm, with some branches supplying the head and thorax. On the left side of the body, the subclavian comes directly off the aortic arch, while on the right side it arises from the relatively short brachiocephalic artery when it bifurcates into the subclavian and the right common carotid artery.
A tracheal tube is a catheter that is inserted into the trachea for the primary purpose of establishing and maintaining a patent airway and to ensure the adequate exchange of oxygen and carbon dioxide.
Airway management includes a set of maneuvers and medical procedures performed to prevent and relieve airway obstruction. This ensures an open pathway for gas exchange between a patient's lungs and the atmosphere. This is accomplished by either clearing a previously obstructed airway; or by preventing airway obstruction in cases such as anaphylaxis, the obtunded patient, or medical sedation. Airway obstruction can be caused by the tongue, foreign objects, the tissues of the airway itself, and bodily fluids such as blood and gastric contents (aspiration).
Respiratory arrest is a serious medical condition caused by apnea or respiratory dysfunction severe enough that it will not sustain the body. Prolonged apnea refers to a patient who has stopped breathing for a long period of time. If the heart muscle contraction is intact, the condition is known as respiratory arrest. An abrupt stop of pulmonary gas exchange lasting for more than five minutes may permanently damage vital organs, especially the brain. Lack of oxygen to the brain causes loss of consciousness. Brain injury is likely if respiratory arrest goes untreated for more than three minutes, and death is almost certain if more than five minutes.
Stridor is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the pharynx.
The aortic arch, arch of the aorta, or transverse aortic arch is the part of the aorta between the ascending and descending aorta. The arch travels backward, so that it ultimately runs to the left of the trachea.
The thyroid ima artery is an artery of the head and neck. It is an anatomical variant that, when present, supplies blood to the thyroid gland primarily, or the trachea, the parathyroid gland and the thymus gland in rare cases. It has also been reported to be a compensatory artery when one or both of the inferior thyroid arteries are absent, and in a few cases the only source of blood to the thyroid gland. Furthermore, it varies in origin, size, blood supply, and termination, and occurs in around 3.8% of the population and is 4.5 times more common in fetuses than in adults. Because of the variations and rarity, it may lead to surgical complications, particularly during tracheostomy and other airway managements.
Subglottic stenosis is a congenital or acquired narrowing of the subglottic airway. It can be congenital, acquired, iatrogenic, or very rarely, idiopathic. It is defined as the narrowing of the portion of the airway that lies between the vocal cords and the lower part of the cricoid cartilage. In a normal infant, the subglottic airway is 4.5-5.5 millimeters wide, while in a premature infant, the normal width is 3.5 millimeters. Subglottic stenosis is defined as a diameter of under 4 millimeters in an infant. Acquired cases are more common than congenital cases due to prolonged intubation being introduced in the 1960s. It is most frequently caused by certain medical procedures or external trauma, although infections and systemic diseases can also cause it.
Bronchoscopy is an endoscopic technique of visualizing the inside of the airways for diagnostic and therapeutic purposes. An instrument (bronchoscope) is inserted into the airways, usually through the nose or mouth, or occasionally through a tracheostomy. This allows the practitioner to examine the patient's airways for abnormalities such as foreign bodies, bleeding, tumors, or inflammation. Specimens may be taken from inside the lungs. The construction of bronchoscopes ranges from rigid metal tubes with attached lighting devices to flexible optical fiber instruments with realtime video equipment.
Tracheobronchial injury is damage to the tracheobronchial tree. It can result from blunt or penetrating trauma to the neck or chest, inhalation of harmful fumes or smoke, or aspiration of liquids or objects.
Double aortic arch is a relatively rare congenital cardiovascular malformation. DAA is an anomaly of the aortic arch in which two aortic arches form a complete vascular ring that can compress the trachea and/or esophagus. Most commonly there is a larger (dominant) right arch behind and a smaller (hypoplastic) left aortic arch in front of the trachea/esophagus. The two arches join to form the descending aorta which is usually on the left side. In some cases the end of the smaller left aortic arch closes and the vascular tissue becomes a fibrous cord. Although in these cases a complete ring of two patent aortic arches is not present, the term ‘vascular ring’ is the accepted generic term even in these anomalies.
A tracheotome is a medical instrument used to perform an incision in the trachea with a cutting blade operated by a powered cannula. It is often called a tracheostomy tube because once it enters the stoma in the trachea, a breathing tube is connected to a ventilator and oxygen is provided to the lungs.
A laryngeal cleft or laryngotracheoesophageal cleft is a rare congenital abnormality in the posterior laryngo-tracheal wall. It occurs in approximately 1 in 10,000 to 20,000 births. It means there is a communication between the oesophagus and the trachea, which allows food or fluid to pass into the airway.
Tracheal intubation, an invasive medical procedure, is the placement of a flexible plastic catheter into the trachea. For millennia, tracheotomy was considered the most reliable method of tracheal intubation. By the late 19th century, advances in the sciences of anatomy and physiology, as well as the beginnings of an appreciation of the germ theory of disease, had reduced the morbidity and mortality of this operation to a more acceptable rate. Also in the late 19th century, advances in endoscopic instrumentation had improved to such a degree that direct laryngoscopy had finally become a viable means to secure the airway by the non-surgical orotracheal route. Nasotracheal intubation was not widely practiced until the early 20th century. The 20th century saw the transformation of the practices of tracheotomy, endoscopy and non-surgical tracheal intubation from rarely employed procedures to essential components of the practices of anesthesia, critical care medicine, emergency medicine, gastroenterology, pulmonology and surgery.
Advanced airway management is the subset of airway management that involves advanced training, skill, and invasiveness. It encompasses various techniques performed to create an open or patent airway – a clear path between a patient's lungs and the outside world.