Adenotonsillectomy (AT)

Anatomy

• Palatine tonsils: lymphoid tissue in the tonsillar fossae between the anterior (palatoglossal) and posterior (palatopharyngeal) faucial pillars
• Adenoids (pharyngeal tonsil): lymphoid tissue on the posterior nasopharyngeal wall
• Together with the tubal and lingual tonsils, they form Waldeyer's ring

Indications

Absolute Indications

• Obstructive sleep apnoea (OSA) / sleep-disordered breathing causing chronic airway obstruction, cor pulmonale
• Suspected tonsillar malignancy

Relative Indications

• Recurrent acute tonsillitis (see Paradise criteria below)
• Chronic tonsillitis
• Peritonsillar abscess (quinsy) - especially recurrent
• Tonsillar asymmetry (if malignancy needs to be excluded)
• Tonsillitis causing febrile convulsions
• Diphtheria carriers
• Systemic disease caused by beta-haemolytic Streptococcus (rheumatic fever, glomerulonephritis)

Paradise Criteria (for recurrent tonsillitis)

• 7 sore throat episodes in 1 year, OR
• 5 episodes per year for 2 consecutive years, OR
• 3 episodes per year for 3 consecutive years

Evidence Base

For Obstructive Sleep-Disordered Breathing (the main indication today)

• No significant difference in the primary outcome (neuropsychological testing)
• Significant improvement in secondary quality-of-life outcomes in the surgical group
• 46% spontaneous resolution in the control arm vs. 79% in the AT arm
• Supports the observation that symptoms can resolve spontaneously after age 5 due to natural reduction in adenotonsillar volume

For Recurrent Infection

• The Paradise trial (1984) showed tonsillectomy was efficacious for 2-3 years in severely affected children
• The NESTAC (North of England and Scotland Study) used similar criteria and confirmed benefit in randomized and parallel cohort children
• Overall the evidence is modest - a 2015 Cochrane review found only 3 trials meeting criteria for obstructive indications

Surgical Techniques

1. Cold Steel Dissection (Traditional "Gold Standard")

• Tonsil is retracted medially; mucosa over the capsule is incised; blunt dissection separates the tonsil from the pharyngeal musculature in the loose areolar plane; haemostasis with ties or diathermy
• Associated with the lowest secondary haemorrhage rates per the UK National Prospective Tonsillectomy Audit (NPTA, n>50,000)

2. Diathermy Techniques

• Monopolar and bipolar diathermy forceps - faster but associated with higher secondary haemorrhage rates
• Cold steel + monopolar diathermy has low primary but higher secondary bleeding (2.4%)

3. Coblation

• Radiofrequency energy at lower temperatures (~60°C) to dissolve tissue
• Proposed advantage: reduced thermal spread and postoperative pain
• Secondary haemorrhage rate slightly higher than cold steel alone

Haemorrhage Rates by Technique (NPTA data):

Adenoidectomy Component

• Adenoids are removed via the nasopharynx (typically by curettage, suction diathermy, or microdebrider)
• Evidence for adenoidectomy alone in recurrent acute otitis media (AOM) shows a modest benefit in children who have had prior ventilation tube insertion (31% reduction in AOM, 50% reduction in need for further tubes)
• Little evidence supports AT specifically for AOM in children without prior tube insertion

Perioperative Considerations

• Performed under general anaesthesia
• Ideally when tonsils are not acutely inflamed
• Blood type and screen in children under 15 kg
• Patients are encouraged to eat normally post-op and take regular oral analgesics
• Referred otalgia (via glossopharyngeal nerve) is common and should be warned about
• Day-case or overnight stay is typical

Complications

• Bailey and Love's Short Practice of Surgery, 28th Edition, pp. 807-808
• Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol 2, pp. 344, 481-482

Adenotonsillectomy - Step-by-Step Surgical Procedure

1. Preoperative Preparation

• Consent: Explain risks - haemorrhage (primary and secondary), infection, pain, referred otalgia, dental injury, velopharyngeal insufficiency, airway complications
• Timing: Ideally performed when tonsils are not acutely inflamed
• Blood: Type and screen in children under 15 kg (transfusion rarely needed but must be prepared)
• Clotting history: Screen for bleeding tendencies; postpone if clotting abnormality suspected
• Loose deciduous teeth: Consent to remove under anaesthetic if present, to prevent inhalation
• Contraindication: Submucous cleft palate (risk of velopharyngeal insufficiency) - adenoidectomy is contraindicated in these patients unless airway obstruction is severe

2. Anaesthesia

• General anaesthesia is mandatory
• Anticholinergic agent administered to reduce pharyngeal secretions
• If history of airway obstruction/OSA: inhalational induction without initial paralysis, until the ability to ventilate with positive pressure is confirmed
• Endotracheal tube: A preformed/reinforced RAE tube (Ring-Adair-Elwyn) is preferred - reduces kinking by the self-retaining mouth gag
• Throat pack is placed to prevent blood pooling in the stomach
• Antiemetics given preoperatively (post-op vomiting is common)

3. Patient Positioning

• Patient placed supine with neck extended (shoulder roll placed under the shoulders)
• Head ring used to stabilise the head
• Surgeon sits at the head end of the table

4. Mouth Opening & Exposure

• A Boyle-Davis mouth gag (self-retaining gag) is inserted to hold the mouth open and depress the tongue
• The gag is supported on a Draffin rod/Dott's bar attached to the table
• Care taken with the teeth - in children with erupted secondary incisors, use an adult-sized gag positioned lateral to the incisors to avoid dental trauma

5. Tonsillectomy (Dissection Technique - Cold Steel)

• The anterior faucial pillar (palatoglossal arch) mucosa is grasped with Gwynne-Evans forceps and retracted medially
• A curved scissors or knife incises the mucosa over the tonsil capsule

• The incision enters the loose areolar plane between the tonsil capsule and the underlying pharyngeal constrictor muscles

• Using a periosteal elevator or gauze dissector, the tonsil is dissected away from its bed in the avascular areolar plane
• Dissection proceeds from the upper pole downward

• The tonsil is left attached only by its inferior pedicle (attached to the lingual tonsil inferiorly)
• A tonsil snare or scissors divides this pedicle
• A tonsil swab is packed into the bed and pressure applied for several minutes

• Bleeding points controlled by ligature (ties) or bipolar diathermy
• Cold steel + ties gives the lowest secondary haemorrhage rate (~1.0%)
• Repeat on the contralateral side

6. Adenoidectomy

Technique Options:

• Digital palpation of nasopharynx to assess adenoid size
• A St Clair-Thomson or Beckmann adenoid curette is guided into the nasopharynx and the adenoid tissue scraped away
• A post-nasal pack or swab placed for haemostasis
• Disadvantages: blind procedure, unpredictable bleeding (~50 mL), risk of trauma to the Eustachian tube cushions (torus tubarius)

• A post-nasal mirror or angled scope provides direct view of the nasopharynx
• Suction coagulator ablates the adenoid tissue under direct vision
• Mean blood loss only ~4 mL vs ~50 mL with curettage
• Provides haemostasis during the procedure; negligible risk of post-op haemorrhage
• Allows partial adenoidectomy (leaving inferior ridge to prevent velopharyngeal insufficiency)

• Direct-vision techniques
• Microdebrider is ~20% faster than curettage
• Coblation offers less blood loss and more complete removal
• Higher unit cost

7. End of Procedure

• Before removing the gag, the nasopharynx must be suctioned to clear any pooled blood/clot
• Failure to do this risks the clot falling onto the larynx during recovery causing fatal acute airway obstruction - the so-called "coroner's clot"
• If swabs were used, swab count must be confirmed correct before removing the gag
• Gastric contents aspirated via nasogastric tube prior to extubation (reduces aspiration risk)

8. Extubation

• Awake extubation is generally preferred - reduces aspiration risk
• Deep extubation is sometimes used to prevent laryngospasm and blood clot dislodgment from coughing, but carries aspiration risk
• Patient placed in the lateral/tonsillar position (left lateral, head slightly down) during recovery to allow blood/secretions to drain away from the airway

9. Postoperative Care

• Recovery room: Close monitoring for haemorrhage - regular pulse, BP, and observation for excessive swallowing (sign of bleeding)
• Diet: Encouraged to eat and drink normally post-op (helps with debridement of the tonsillar bed and reduces secondary haemorrhage)
• Analgesia: Regular oral analgesics (e.g. paracetamol, NSAIDs)
• Day case or overnight stay depending on age and clinical condition; children <3 years with OSA should be admitted overnight
• Discharge advice: Warn parents about:
  • Referred otalgia (via glossopharyngeal nerve - CN IX) - does not imply ear infection
  • Risk of secondary haemorrhage up to 10 days post-operatively
  • Return immediately if bleeding occurs

Summary of Surgical Technique Comparison