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EN4.{30,35-36,46} | Head Neck and Systemic ENT — PBL Case

CLINICAL SETTING

It is a Friday evening when Dr Meera Nair, a final-year resident in ENT at a teaching hospital in Kerala, receives an emergency referral from the general surgery team. The patient, Mr Ramesh — a 44-year-old schoolteacher with poorly controlled type 2 diabetes — was brought in earlier with a five-day history of worsening right lower molar toothache. He developed fever, trismus, and a progressive submandibular swelling that spread bilaterally over the last 24 hours. By the time he reaches the ENT emergency, Ramesh is in distress: his mouth is barely open (trismus, <1 cm inter-incisal distance), he is drooling, his speech is muffled, and his neck is hard and board-like bilaterally from the mandible to the clavicle. His wife says 'the swelling appeared soft at first and now it's like wood'. His temperature is 39.6°C, heart rate 118 bpm, respiratory rate 24 breaths/min, SpO₂ 93% on room air, and there is audible stridor on inspiration. The surgical resident had initially planned incision and drainage under local anaesthesia, but the ENT nurse immediately flags Dr Nair: 'Doctor, this man cannot open his mouth and his neck is swelling — I'm worried about his airway.' Dr Nair pauses at the bedside, assessing the patient while simultaneously reviewing his blood results: random blood glucose 18.4 mmol/L, WBC 22,000 with 90% neutrophils, CRP 280 mg/L.

Trigger 1: The Airway First Decision

Dr Nair has three minutes to make a decision. The surgical resident suggests direct laryngoscopy and orotracheal intubation. The anaesthesia team is being called. A fibreoptic nasendoscopy shows oropharyngeal oedema with elevation of the floor of the mouth and near-complete obliteration of the vallecula. The epiglottis is oedematous. Direct laryngoscopy grade IV — no glottic structures visible. The hospital's emergency resources include: a fibreoptic intubation scope (available in 20 minutes), a tracheostomy tray (at bedside), and a cricothyroidotomy kit. The anaesthetist on call says 'I can try one attempt at video laryngoscopy but I can't guarantee success with this much neck swelling.' Concurrently, the CT scanner is ready. The radiologist asks: 'Do you want a CT before or after securing the airway?'

DISCUSSION POINTS

What is the correct answer to the radiologist's question — CT before or after airway securing — and why? State the clinical principle.
Given the fibreoptic nasendoscopy findings, grade IV laryngoscopy, and SpO₂ of 93%, which airway management technique should Dr Nair recommend: (a) awake fibreoptic intubation, (b) video laryngoscopy attempt, or (c) surgical airway (tracheostomy)? Justify using the clinical evidence in the scenario.
Name the specific deep neck spaces involved in this patient's bilateral submandibular and floor-of-mouth presentation. What is the anatomical pathway that makes this patient at risk of losing his airway from a 'bottom-up' rather than a 'top-down' process?
The surgical resident had planned incision and drainage under local anaesthesia. Why is this approach potentially catastrophic in this patient's current state?

Click to reveal Trigger 2: CT Findings and Bacteriology (discuss previous trigger first!)

Trigger 2: CT Findings and Bacteriology

The airway is secured with an awake tracheostomy under local anaesthesia and sedation (the safest route given grade IV laryngoscopy and impending obstruction). A CECT neck and thorax is now performed. CT report: 'Bilateral submandibular, sublingual, and submental space cellulitis and early abscess formation. Gas bubbles noted within the left submandibular space consistent with necrotising infection. Extension of infection noted into the right parapharyngeal space. The retropharyngeal space shows streaky enhancement and fluid extending inferiorly to the level of T4, suggestive of early descending necrotising mediastinitis. No free mediastinal fluid yet.' Intraoperative pus culture grows Streptococcus milleri group (viridans streptococcus) + Klebsiella pneumoniae in a polymicrobial pattern. Blood cultures are negative. The microbiologist recommends broad-spectrum coverage: IV piperacillin-tazobactam + metronidazole, with an urgent diabetes review. Mr Ramesh's wife pulls Dr Nair aside: 'Doctor, I am very worried. My son has been reading online and says my husband's infection has spread to the chest. Is he going to die? Was this caused by the dentist's mistake?' She is in tears.

DISCUSSION POINTS

The CT shows infection extending down the retropharyngeal/danger space to T4 level. Name the fascial space responsible for this descent and explain the anatomical boundaries that make it a 'danger space'.
The gas bubbles in the submandibular space suggest necrotising infection. What does this finding change about the surgical management plan — specifically regarding the type and extent of debridement required?
The microbiologist recommends piperacillin-tazobactam + metronidazole. Explain the rationale: what does piperacillin-tazobactam cover, and why is metronidazole added given the polymicrobial culture result?
How does Dr Nair answer the wife's two questions accurately and empathetically: (a) Is he going to die? (b) Was this the dentist's fault? What risk communication principles should guide her response?

Click to reveal Trigger 3: Recovery, Complications and a New Finding (discuss previous trigger first!)

Trigger 3: Recovery, Complications and a New Finding

Day 7: Mr Ramesh has undergone urgent bilateral cervical drainage with thoracic surgical consultation (no mediastinal abscess requiring mediastinotomy — managed conservatively with antibiotics). He is on the general ENT ward, tracheostomy in situ, tolerating oral feeds, temperature settling. Diabetes is now under adequate control. On morning ward round, Dr Nair notices: Ramesh has a new finding. He has developed a right facial weakness (forehead sparing) — new since Day 2. The medical student asks if this is a Bell's palsy. Additionally, the ward team note a slow-growing hard right submandibular swelling that was present on admission but presumed to be lymphadenopathy. It has not changed with the antibiotics. FNAC of this submandibular lump shows: 'Epithelial and myoepithelial cells in a chondromyxoid stroma.'

DISCUSSION POINTS

The medical student says this is 'probably Bell's palsy since he has been unwell'. Why is this incorrect? Name the correct diagnosis given the context (deep neck infection, parapharyngeal space extension noted on CT) and the mechanism of the facial nerve palsy.
The FNAC of the right submandibular swelling shows 'epithelial and myoepithelial cells in a chondromyxoid stroma'. Name the tumour. What is the treatment? State ONE absolute surgical safety rule that applies to the management of this tumour — regardless of which salivary gland it arises in.
Mr Ramesh's diabetes is identified as the key predisposing factor throughout his admission. Using the evidence from this case, construct a 'learning issue' for the group: what is the mechanism by which uncontrolled diabetes increases susceptibility to polymicrobial necrotising infections of the deep neck spaces?
At discharge, Ramesh asks if he will need the tracheostomy forever. Describe the decannulation criteria and the typical timeline for tracheostomy removal after a successfully managed deep neck space infection.

Group Task Assignments

Group 1: Airway Emergency and Deep Neck Anatomy

Map all the deep neck spaces involved in Ludwig's angina using a labelled sketch — identify which spaces communicate with which, and trace the anatomical route from the mandibular molar root to the posterior mediastinum
Prepare a decision flowchart for airway management in a patient with deep neck infection: what clinical findings at each step change the choice (awake fibreoptic vs video laryngoscopy vs surgical airway)?
State the three simultaneous management priorities in deep neck space infection and the specific investigations required for each

Competencies: EN4.36

Group 2: Microbiology, Antibiotics and Surgical Drainage

Research the polymicrobial bacteriology of Ludwig's angina: name the three most common organism groups, classify them as aerobic/anaerobic, and explain why the combination of piperacillin-tazobactam + metronidazole provides appropriate coverage
Explain what the presence of gas bubbles on CT means for the organism type and surgical management — specifically the difference between cellulitis and necrotising fasciitis surgical approach
Define descending necrotising mediastinitis: name the three diagnostic criteria used to confirm it on CT (Endo criteria), and describe the surgical approach when mediastinal abscess is confirmed

Competencies: EN4.36

Group 3: Salivary Gland Pathology

Compare pleomorphic adenoma and Warthin's tumour: site of predilection, FNAC findings, bilateral occurrence rate, malignant transformation risk, and surgical management
Explain why incisional biopsy is absolutely contraindicated for parotid masses — name two specific consequences that make this a non-negotiable safety rule
List the indications for superficial vs total conservative vs radical parotidectomy — what intraoperative finding would change a conservative procedure to a radical one?

Competencies: EN4.35

Group 4: Facial Nerve and Head and Neck Trauma

Distinguish upper motor neurone (UMN) vs lower motor neurone (LMN) facial palsy clinically — in this case, how does parapharyngeal space infection cause a LMN facial palsy?
Review the management of temporal bone fractures: compare longitudinal vs transverse fracture in terms of mechanism, hearing loss type, vestibular involvement, and facial nerve palsy rate
Define the septal haematoma rule: what is the pathophysiology of avascular necrosis following untreated haematoma, and what does the surgical drainage procedure involve?

Competencies: EN4.30

Group 5: HIV and Systemic ENT

Create a table of HIV-associated ENT manifestations organised by region (oral cavity, salivary glands, neck, ear, larynx) — for each, state the causative organism, CD4 threshold, and first-line management
Compare oral hairy leukoplakia with oral candidiasis on five clinical criteria: site, appearance, wipeability, organism, and treatment
Explain the concept of immune reconstitution inflammatory syndrome (IRIS) in the context of ENT — name two ENT conditions where ART initiation can paradoxically worsen the condition before improving it

Competencies: EN4.46

Learning Issues

Research these questions and bring your findings to the discussion.

[EN4.36] What are the deep neck spaces and their fascial boundaries? Which spaces communicate with each other and which communicates directly with the posterior mediastinum?
[EN4.36] What is Ludwig's angina? Describe its clinical features, the three spaces involved, common bacteriology, and the principle that guides all management decisions (airway first).
[EN4.36] What is descending necrotising mediastinitis? What are the Endo CT criteria for diagnosis? When is thoracic surgical input required versus conservative management adequate?
[EN4.30] Classify temporal bone fractures. For each type, state the hearing loss pattern, vestibular involvement, rate of facial nerve palsy, and typical management.
[EN4.30] What is septal haematoma? Why must it be drained urgently? Describe the pathophysiological sequence from haematoma to saddle nose deformity.
[EN4.35] Compare pleomorphic adenoma and Warthin's tumour: epidemiology, FNAC findings, malignant transformation risk, bilateral occurrence, and surgery.
[EN4.35] What are the absolute surgical safety rules in parotid surgery? Why is incisional biopsy absolutely contraindicated? What are the steps of identifying the facial nerve during parotidectomy?
[EN4.46] List the common ENT manifestations of HIV in the oral cavity, salivary glands, neck, and ear. For each, state the causative organism, CD4 threshold at which it typically appears, and specific treatment.
[EN4.46] Describe oral hairy leukoplakia: causative agent, clinical appearance, distinguishing features from oral candidiasis, and management.