Continuing Education Activity

Tapia syndrome is a rare disease characterized by concurrent unilateral hypoglossal and recurrent laryngeal nerve palsy. The injury mechanism is closely related to airway manipulation leading to direct compression or excessive stretch of the nerves. Diagnosis is made through a process of exclusion and can be challenging for clinicians due to its relative infrequency. This article reviews Tapia's syndrome's etiology and pathophysiology with particular attention to the interprofessional team's role in the evaluation and treatment of patients suffering this condition.

Objectives:

• Outline the typical presentation of Tapia syndrome.
• Describe the relevant anatomy of the hypoglossal and recurrent laryngeal nerves concerning Tapia syndrome.
• Identify the main diagnostic tests for Tapia syndrome.
• Review some interprofessional team strategies that can improve care coordination and better outcomes for patients with Tapia syndrome.

Introduction

Tapia syndrome was first described by Spanish otorhinolaryngologist Antonio Garcia Tapia in 1904 as a lesion outside the central nervous system causing neurological signs and symptoms.[1] Nowadays, it is recognized as a rare complication of airway manipulation, with less than 100 cases described in the literature. The syndrome is characterized by unilateral paralysis of the tongue and vocal cord, manifesting as dysphonia, tongue deviation, and swallowing difficulty.[2] Although there is an increased propensity with specific procedures, Tapia syndrome can technically occur with any surgery requiring general anesthesia and orotracheal intubation.[3]

Etiology

Tapia syndrome results from concurrent unilateral paralysis of the hypoglossal (XII) and the recurrent laryngeal branch of the vagus (X) nerve. Rare cases of bilateral paralysis of these nerves have also been reported.[4] Injury to the nerve can occur anywhere along its path, either centrally (intra-cranial) or peripherally (extra-cranial).

Tapia syndrome typically manifests as the unilateral and peripheral form of nerve damage from direct trauma to the hypoglossal and recurrent laryngeal nerve at the base of the tongue and pyriform fossae.[5] By far, the most typical cause is orotracheal intubation for general anesthesia, exacerbated by neck hyperextension.

The central type of Tapia syndrome typically forms part of a brainstem syndrome affecting the hypoglossal nucleus, nucleus ambiguus, and pyramidal tract.[6] Causes include hemorrhage, ischemia, abscess formation, malignancies, and other space-occupying lesions. Central Tapia syndrome is incredibly rare, and fewer than 5 cases have been reported in the literature, attributed to brainstem infarctions, meningovascular syphilis, and metastatic haemangiosarcoma.[7][8]

Epidemiology

Tapia syndrome has a close association with surgical procedures involving general anesthesia and orotracheal intubation. Main factors that impact incidence appear to be the duration of intubation, neck positioning, and upper limb manipulation about the head. This is supported by reports in intensive care units, cervical spine surgery, and shoulder arthroscopy.[9][10][11][12][10] Cases have also been recognized in cardiothoracic, otolaryngology, and maxillofacial surgeries.[13][14][15]

Pathophysiology

The hypoglossal nerve (cranial nerve XII) starts in the hypoglossal nucleus of the medulla. It passes between the olive and pyramid of the anterior brainstem before exiting the cranial cavity through the hypoglossal canal. Then, it receives contributions from cervical nerves as it enters the neck between the internal carotid artery and internal jugular vein. Upon reaching the tongue's lateral aspect, it lies close to the hyoglossus muscle and inferior to the lingual nerve. The hypoglossal nerve only has the motor function and controls all the intrinsic and extrinsic muscles of the tongue.

The motor fibers to the laryngeal and pharyngeal muscles begin in the nucleus ambiguus and exit the medulla at the root of the accessory nerve to join the vagus nerve (cranial nerve X) before exiting the jugular foramen and traveling within the carotid sheath in the neck. The recurrent laryngeal nerves eventually branch off the vagus, wrapping underneath the right subclavian artery on the right and aortic arch on the left. The nerves then ascend in the groove between the trachea and esophagus to reach the larynx, supplying all the larynx's intrinsic muscles except the cricothyroid muscles.

Damage to these nerves at any point in its course can result in neuropraxia (mild, temporary loss of function) or axonotmesis (usually permanent, irreversible damage).[1] One injury mechanism is thought to be pressure neuropathy of the nerves secondary to a difficult laryngoscopy, malpositioning or overinflation of the endotracheal tube, and extubation with an inflated cuff.[16][17] 

The hypoglossal and recurrent laryngeal nerve are located adjacent to the oropharynx junction and the hypopharynx; thus, this area is where concurrent injury and paralysis most likely arise.[5] An excessive stretch of the hypoglossal nerve from neck manipulation can occur on the anterior surface of the first cervical transverse process as it intersects the vagus nerve, causing the syndrome.[18] Other risk factors for nerve injury include placement of a throat pack or neck manipulation intra-operatively.[2]

History and Physical

Tapia syndrome is a diagnosis of exclusion, made principally upon clinical grounds. In patients who have undergone orotracheal intubation, the onset of signs and symptoms often occurs very quickly after extubating and usually includes hoarseness, difficulties in speech and swallowing, and ipsilateral tongue deviation upon protrusion.[1]

A complete history and detailed neurological examination are required to exclude other findings and confirm whether the cause is central or peripheral. Intracranial nerve lesions present with upper motor neuron signs and simultaneous palsies of other nerves, whereas extracranial injuries generally result in isolated nerve palsies. Any additional localizing signs should be discussed and referred to relevant specialists for further investigation and management.

Aktas and Boga proposed in 2010 a classification and treatment protocol for Tapia syndrome that has not yet been validated. This provides a practical framework for diagnosis but should be used for guidance purposes only.[1]

Evaluation

Computed tomographic (CT) scan and magnetic resonance imaging (MRI) are essential to rule out central causes of Tapia syndrome. CT scan remains the initial imaging modality of choice, despite being inferior to MRI, as it is readily available.

Neurology input and electromyography may also provide some additional information but is unlikely to alter the diagnosis or management.

Visual confirmation of nerve paralysis can also be obtained using airway endoscopy on swallowing tests, in which saliva will be seen pooling in the piriform sinus.[19] Depending on the degree of clinical suspicion, airway endoscopy may provide a safe and reliable diagnosis, thereby avoiding the unnecessary use of CT, MRI, barium swallow, or electromyography.

Treatment / Management

The mainstay of treatment in Tapia syndrome is rehabilitation. As the recovery process can take many months, early speech and language therapy involvement and establishing a structured swallowing rehabilitation program are crucial for a good outcome. There is a clear consensus that a multidisciplinary approach is needed for the correct management of this syndrome.

The role of steroids in treating Tapia syndrome remains controversial, without any clear evidence, and should be guided by neurologists.[20] In the absence of contraindications, early steroid therapy may reduce nerve swelling and enhance recovery based on the disease mechanism. In mild (grade I) cases, no steroids are recommended. For moderate (grade II) cases, 15 days of corticosteroid treatment (first three days intravenously; followed by oral route) can be given. Severe (grade III) cases can receive one week of intravenous corticosteroid (1 mg/kg per day) treatment.[1]

Differential Diagnosis

Tapia syndrome is almost always associated with orotracheal intubation and surgical intervention. Hence, any presentation that lacks a history of direct trauma should be a cause for concern. The main pathologies to exclude are space-occupying lesions and infection, some of which are listed below:

• Lung cancer: Left-sided tumors causing compression of left recurrent laryngeal nerve
• Ortner’s syndrome: Left recurrent laryngeal nerve palsy due to expansion of structures within heart and major blood vessels
• Malignant lymph nodes
• Head and neck tumors
• Abscess formation

Prognosis

Time for recovery ranges between 3-22 months with a median of 9 to 12 months.[6] Complete recovery occurs in approximately 30% of patients, incomplete in 39% of patients, and no recovery in over 26% of patients.[16]

Complications

Tapia syndrome is not always reversible and can lead to significant morbidity. Incomplete recovery can leave patients with permanent speech and swallowing difficulties, resulting in poor feeding, inadequate nutrition, and a high risk of aspiration. Severe bilateral vocal cord paralysis in Tapia syndrome may present as airway emergencies, necessitating tracheostomy.

Consultations

• Surgeon
• Anesthesiologist
• Radiologist
• Neurologist
• Otolaryngologist
• Speech and language therapist

Deterrence and Patient Education

Patients undergoing procedures that are high-risk for Tapia syndrome should be counseled about the potential risks of nerve injury as part of the consent process. Awareness and knowledge of the disease process can help clinicians avoid unnecessary investigations and provide patients with informed judgment about prognosis and outcome.

Enhancing Healthcare Team Outcomes

Diagnosis and management of Tapia syndrome require a multidisciplinary approach to achieve the best outcomes and ensure patient safety. This involves surgeons, anesthesiologists, radiologists, neurologists, otolaryngologists, and speech and language therapists. Due to its relative scarcity, reaching a diagnosis early on should be taken with caution. Surgeons and anesthesiologists are most likely to be consulted on the initial presentation. Neurology input is recommended both for diagnosis and treatment, particularly if steroids are being considered. Requesting and reviewing cross-sectional imaging with radiologists may also be necessary to combine clinical and radiological findings. Also, otolaryngologists can perform airway endoscopy and provide a different perspective on potential diagnoses. Ultimately, rehabilitation forms the cornerstone for recovery, and this is primarily handled by the speech and language therapists.