Tonsillectomy – Anesthetic Considerations

Anesthesia for tonsillectomy presents challenges such as:

Airway management in the presence of enlarged tonsils

Risk of perioperative bleeding and aspiration

High incidence of postoperative nausea and vomiting (PONV)

Postoperative airway obstruction due to edema or blood clot formation


1. Indications for Tonsillectomy

A. Infective Indications

Recurrent tonsillitis:

• ≥ 7 episodes in 1 year

• ≥ 5 episodes per year for 2 consecutive years

• ≥ 3 episodes per year for 3 consecutive years

Peritonsillar abscess (Quinsy) – failure of medical therapy

Chronic tonsillitis with halitosis

B. Obstructive Indications

Obstructive Sleep Apnea (OSA)

Severe tonsillar hypertrophy causing dysphagia, speech issues, or failure to thrive

C. Other Indications

Suspicion of malignancy (asymmetry, rapid growth)

Hemicrania continua (rare)


2. Preoperative Considerations

A. Airway Evaluation

Assess for tonsillar hypertrophy (Grades I–IV).

Mallampati score and sleep study (if OSA is suspected).

Evaluate nasal obstruction (if adenoid hypertrophy is present).

B. Medical History

Recurrent infections, recent URTI (Postpone surgery if URTI within 2 weeks).

Bleeding disorders (von Willebrand disease, hemophilia).

Allergies to antibiotics or anesthetic drugs.


3. Intraoperative Anesthetic Considerations

A. Choice of Anesthesia

General anesthesia (GA) with endotracheal intubation (to protect against aspiration).

Rapid Sequence Induction (RSI) may be needed in cases with severe OSA.


B. Airway Management

Technique

Advantages

Disadvantages

Oral Endotracheal Tube (ETT) – Cuffed

Prevents aspiration, allows controlled ventilation

Risk of tube displacement due to oral retractors

Nasal ETT

Better surgical access

Increased risk of epistaxis

Laryngeal Mask Airway (LMA) (selected cases)

Less airway irritation, quick recovery

Not recommended in OSA or difficult airway cases

Oral RAE (Ring-Adair-Elwyn) tube is commonly used as it provides a secure airway and allows adequate surgical access.


C. Anesthetic Drugs

Induction:

• Propofol (2-3 mg/kg) ± Fentanyl (1-2 mcg/kg)

• Sevoflurane (preferred in pediatric cases)

• Neuromuscular blockade: Rocuronium (0.6 mg/kg) or Succinylcholine (in emergencies)

Maintenance:

• Sevoflurane/Desflurane with air/O₂ ± N₂O

• Dexamethasone (0.15 mg/kg, max 8 mg IV) – reduces edema and PONV

• Paracetamol (15 mg/kg IV) ± NSAIDs for analgesia

Analgesia:

• IV paracetamol + opioids (fentanyl or morphine in small doses)

Avoid codeine in children (risk of respiratory depression due to CYP2D6 polymorphism).


4. Intraoperative Challenges

A. Bleeding

Tonsils are highly vascular (branches of external carotid artery – facial, lingual, ascending pharyngeal arteries).

Surgical techniques:

• Cold dissection method – less risk of thermal injury, higher bleeding risk.

• Electrocautery or coblation – reduces bleeding but may cause delayed healing.

B. Airway Fire Risk (if cautery is used)

Minimize FiO₂ (<30%) to reduce fire risk.

Avoid N₂O (supports combustion).

C. Extubation Considerations

Fully awake extubation is preferred to prevent aspiration.

Gentle suctioning of blood in the pharynx before extubation.

Risk of laryngospasm Deep extubation in selected cases with OSA or reactive airways.


5. Postoperative Care

A. Airway Monitoring

Monitor for airway obstruction due to edema or bleeding.

Patients with severe OSA or significant edema Consider overnight observation in ICU.

B. Pain Management

Multimodal analgesia (IV Paracetamol ± NSAIDs ± opioids).

Avoid aspirin or NSAIDs in high-risk bleeding patients.

C. Postoperative Nausea & Vomiting (PONV)

High incidence (up to 60%) due to blood ingestion.

Prophylaxis:

• Ondansetron (0.15 mg/kg IV)

• Dexamethasone (4-8 mg IV)

D. Post-Tonsillectomy Hemorrhage

Primary bleeding (<24 hrs) – surgical site issue.

Secondary bleeding (5-10 days) – due to sloughing of eschar.

Management:

• IV fluids, oxygen, blood transfusion if required.

• Urgent re-exploration if bleeding is significant.


 MCQs on Tonsillectomy Anesthesia

1. The most common complication after tonsillectomy is:

A) Laryngospasm

B) Airway fire

C) Postoperative bleeding

D) Vocal cord injury

Answer: C (Post-tonsillectomy bleeding is the most common serious complication).


2. Which drug is preferred to reduce postoperative nausea in tonsillectomy?

A) Metoclopramide

B) Ondansetron

C) Haloperidol

D) Diphenhydramine

Answer: B (Ondansetron is the first-line antiemetic).


3. Why should NSAIDs be used cautiously after tonsillectomy?

A) Risk of bronchospasm

B) Risk of renal failure

C) Increased risk of bleeding

D) Increased risk of PONV

Answer: C (NSAIDs can impair platelet function and increase bleeding risk).