Deep Neck Infections

Infections involving the fascial spaces of the neck, most commonly arising from odontogenic, tonsillar or pharyngeal sources, representing a potentially life threatening emergency given the risk of airway compromise, mediastinal extension and vascular complications, requiring prompt recognition, imaging and, frequently, surgical drainage alongside antibiotic therapy.

Anatomy and spread

The deep cervical fascia divides the neck into distinct spaces including the peritonsillar, parapharyngeal, retropharyngeal and submandibular spaces, which communicate with one another and with the mediastinum, explaining the potential for rapid spread of infection from an apparently localised source to a life threatening deep space collection and, in severe cases, descending mediastinitis.

Fever, neck pain and swelling, trismus, odynophagia and, depending on the specific space involved, a muffled voice (peritonsillar or parapharyngeal involvement) or torticollis and neck stiffness (retropharyngeal involvement) characterise the typical presentation.

Ludwig angina, a specific bilateral submandibular and sublingual space infection typically arising from a dental source, presents with a rapidly progressive, board like induration of the floor of the mouth, tongue elevation and posterior displacement, and represents a particular airway emergency given the risk of rapid, life threatening obstruction.

Red flag features requiring immediate assessment include stridor, drooling, significant trismus limiting examination, and signs of sepsis, any of which mandate urgent involvement of anaesthetic and ear, nose and throat teams for airway assessment and securing before any other intervention.

Contrast enhanced computed tomography of the neck is the investigation of choice, defining the extent of the infection, identifying any drainable collection, and assessing for extension toward the mediastinum or major vascular structures.

Full blood count, inflammatory markers and blood cultures support assessment of severity and identification of the causative organism, with culture of any drained pus guiding subsequent targeted antibiotic therapy.

Airway assessment takes absolute priority over imaging in any patient with stridor or significant respiratory distress, with imaging deferred until the airway is secured if there is any doubt regarding stability.

Airway management takes precedence over all other interventions, with early involvement of an experienced anaesthetist and surgeon for any patient with actual or impending airway compromise, since intubation can be extremely difficult in this context and awake fibreoptic intubation or surgical airway may be required.

Empirical intravenous antibiotics covering streptococci, staphylococci and anaerobic organisms are started promptly: co amoxiclav 1.2 g intravenously three times daily is a standard first line choice, with clindamycin 600 mg intravenously three times daily as an alternative in penicillin allergy, and piperacillin with tazobactam 4.5 g intravenously three times daily or a carbapenem considered for more severe or hospital associated infection, adjusted once culture results are available.

Surgical drainage is indicated for any significant collection identified on imaging, performed promptly given the risk of progression, with the specific approach (transoral for peritonsillar abscess, external cervical approach for larger parapharyngeal or retropharyngeal collections) determined by the location and extent of the infection.

Ludwig angina specifically requires urgent airway management, high dose intravenous antibiotics, and surgical decompression of the floor of the mouth alongside removal of the causative dental source, given the rapid and potentially fatal progression if not treated aggressively.

Ongoing monitoring for complications, including mediastinal extension (requiring thoracic surgical involvement), jugular vein thrombosis and carotid artery erosion, together with dental assessment and treatment of any identified odontogenic source, completes full management of this group of conditions.