Facial Space Infection

Facial space infection is infection in the deep fascial compartments of the face and neck, usually odontogenic (about 70 percent), and may spread along planes to threaten the airway, mediastinum and brain. Primary spaces include buccal, canine, masticator (masseteric, pterygoid, temporal), submandibular, sublingual and submental; secondary spaces are lateral pharyngeal, retropharyngeal and pretracheal.

• Organisms: mixed aerobic and anaerobic oral flora.
• Risk factors: untreated dental infection, diabetes, HIV, immunosuppression, malnutrition, intravenous drug use.

Fever, painful swelling of the face or neck, trismus, dysphagia, odynophagia, drooling, muffled voice, dyspnoea, and toxic appearance.

• Ludwig angina: bilateral submandibular, sublingual and submental spaces, tense woody swelling, tongue elevation, stridor.
• Parapharyngeal: trismus, medial tonsil displacement, neck swelling; retropharyngeal: neck stiffness, dysphagia.
• Differential diagnosis: peritonsillar abscess, epiglottitis, angioedema, cellulitis, parotitis, sialadenitis, tumours, haematoma, cervical lymphadenitis, tetanus.
• Complications: airway obstruction, mediastinitis, Lemierre syndrome, carotid artery erosion, cavernous sinus thrombosis, brain abscess, sepsis, aspiration pneumonia, osteomyelitis, death.

Clinical, with early imaging; do not stress an unsafe airway.

• CT neck and chest with contrast (extent, abscess, gas, airway); orthopantomogram.
• Full blood count, CRP, glucose, urea, electrolytes, lactate, blood cultures; pus culture at drainage; HIV test.
• Flexible nasendoscopy for airway assessment by senior staff.

Secure the airway, give IV antibiotics and drain collections.

• Supportive: admission to high dependency care, airway monitoring with oxygen, sitting position, IV fluids, analgesia, nil by mouth if surgery is likely, glycaemic control.
• Pharmacological: benzylpenicillin 2.4 g IV every 6 hours (children 50,000 units/kg every 6 hours) with metronidazole 500 mg IV every 8 hours (children 7.5 mg/kg every 8 hours); or ampicillin sulbactam 3 g IV every 6 hours; or ceftriaxone 2 g IV daily with metronidazole; penicillin allergy: clindamycin 600 to 900 mg IV every 8 hours; MRSA risk: add vancomycin 15 to 20 mg/kg IV every 12 hours. Switch to oral amoxicillin clavulanate 625 mg three times daily after 48 hours of improvement to complete 10 to 14 days. Dexamethasone 8 mg IV can be considered for airway oedema under specialist guidance.
• Procedures: airway control (awake fibreoptic or surgical tracheostomy if impending obstruction), surgical drainage (intraoral or external) under general anaesthesia, removal of the source tooth, mediastinal drainage if extension.
• Special groups: pregnancy, benzylpenicillin and metronidazole after the first trimester, with obstetric input; children, early airway involvement and weight based doses; diabetes, insulin and tighter control; HIV, culture for resistant and fungal organisms.
• Red flags: stridor, trismus, drooling, tongue elevation, neck swelling spreading to chest, hoarseness, hypotension, neck stiffness, proptosis.
• Follow-up: daily review; repeat imaging if no improvement at 48 hours; dental treatment after resolution.