Spreading odontogenic infection with a threatened airway and no drainable collection
A 48-year-old man with type 2 diabetes (HbA1c 11.2%) presents on the fifth day of a spreading odontogenic infection from tooth 47. He is drooling, has a muffled 'hot potato' voice, trismus of 15 mm, bilateral brawny submandibular swelling and elevation of the floor of the mouth. Temperature 38.9 °C, heart rate 122, blood pressure 98/60, respiratory rate 24, SpO₂ 94% on room air. Contrast CT shows gas in the submandibular and sublingual spaces and diffuse stranding extending to the parapharyngeal space, with no discrete fluid collection. White cell count 24 × 10⁹/L, glucose 19 mmol/L, creatinine 140 µmol/L. The anaesthetist is 30 minutes away and prefers an asleep fibreoptic intubation in theatre; the night registrar wants to wait for a collection to 'mature' before draining. He has received no antibiotics.
1. Rank the first 60 minutes of management and justify your airway decision, including what you would refuse to do.
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This is a surgical emergency, not an observation. The combination of drooling, voice change, floor-of-mouth elevation and trismus is the clinical definition of an impending airway obstruction; the mortality of Ludwig's-type infection is driven almost entirely by airway loss.
Order of actions.
- Call for help now: anaesthesia, another surgeon, theatre, blood bank and the intensive care unit simultaneously. Do not move him to the CT scanner again, and do not lie him flat.
- High-flow oxygen, continuous monitoring, large-bore access, and blood cultures followed by empiric intravenous antibiotics within the hour. Fluid resuscitation and an insulin infusion for a glucose of 19 mmol/L.
- Awake fibreoptic intubation is the technique of choice, performed in theatre with the surgeon present and a tracheostomy set open. Awake intubation preserves spontaneous ventilation and allows visualisation of a distorted pharynx. The choice is not between fibreoptic and direct laryngoscopy; it is between the technique that maintains spontaneous ventilation and one that risks a 'cannot intubate, cannot ventilate' catastrophe.
What to refuse. Do not perform an asleep induction in a patient with an obstructed upper airway; do not use a blind nasal tube; do not attempt awake direct laryngoscopy with a 15-mm opening; do not delay surgery for a further scan or a 24-hour antibiotic trial. If fibreoptic access is impossible, a surgical airway is the correct fallback, not repeated attempts.
Prepare for failure: a pre-marked neck, the surgeon scrubbed and ready, and a plan stated aloud for the team.
2. Justify your antibiotic choice and the decision to operate despite the absence of a discrete collection on CT.
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Antibiotics. The organisms are polymicrobial - streptococci, Prevotella, Porphyromonas, Fusobacterium and other anaerobes, with staphylococci in the skin-associated spaces. Empirical cover must reach anaerobes effectively. Amoxicillin–clavulanate plus metronidazole, or piperacillin–tazobactam alone, are appropriate choices; a cephalosporin plus metronidazole is a reasonable alternative. Use intravenous, weight-adjusted doses, and review after culture and sensitivity results. Add an antifungal only on evidence. Steroids are sometimes used to reduce oedema, but they are adjunctive and never a substitute for drainage; in a diabetic they can destabilise glycaemia.
Absence of a collection is not an absence of surgical disease. Contrast CT here shows gas and diffuse brawny stranding - that is cellulitis with necrosis and gas-forming organisms. In a patient with a threatened airway, an operation is indicated for the same reason it would be in a necrotising soft tissue infection: to decompress, to remove the infected tooth and to obtain tissue for culture.
Technique. Secure the airway first, then extract the causative tooth and open all involved spaces broadly - submandibular, sublingual, submental, and explore the parapharyngeal space if there is medial displacement of the lateral pharyngeal wall. Place corrugated drains through and through and plan a second look within 24–48 h. Do not depend on needle aspiration or on a 'drainable' collection.
The registrar's plan to wait is the classic fatal error: in an airway-threatening anaerobic infection, waiting for fluctuance increases both the need for tracheostomy and mortality.
3. What determines intensive care admission, timing of extubation and imaging after surgery, and what must be documented?
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ICU admission is indicated for airway observation, ongoing vasopressor or fluid support, renal impairment (creatinine 140 µmol/L), uncontrolled diabetes with a glucose of 19 mmol/L, and the need for repeat surgical review. A simple ward bed is not adequate after drainage of a submandibular and parapharyngeal infection.
Extubation criteria are clinical and must be planned at the end of the first operation: fever settling, falling white cell count, absence of voice change or stridor, a leak around the deflated cuff, and a decision to reassess in theatre with a second look before removal. A common error is extubation on the following morning based on appearance of the neck rather than on the airway. If there is any doubt, retain the tube or convert with a planned tracheostomy rather than risk a re-intubation in a swollen neck.
Imaging is not routine; repeat contrast CT is indicated if the patient fails to improve within 48 h, if the swelling increases, or if mediastinal extension is suspected (chest imaging).
Documentation - the medico-legal core of this case. Record the time of presentation, the specific airway findings (drooling, voice, floor of mouth), the time of each escalation call, the time antibiotics were given, the airway plan and who agreed it, the decision to operate and its justification despite the CT, the consent discussion including the possibility of tracheostomy, and the diabetes and renal management. When a registrar has proposed watchful waiting and the consultant disagrees, the disagreement and the reasons must be in the notes. Most litigation in this scenario turns on the recorded time-to-drainage and time-to-airway, not on the surgical technique.