When is nasopharyngeal endoscopy contraindicated or in need of special preparation?

Nasopharyngeal endoscopy is a procedure with an extremely low complication profile and virtually no absolute contraindications. Nevertheless, there are a number of clinical situations that call for special caution, a modified technique or postponing the procedure. These situations are summarized below.

I. Safety profile: general data

The prospective series by Hendron et al. (2026, n=143), one of the few studies that specifically assessed complications of flexible nasopharyngoscopy, showed that 62% of patients had no complications at all. Among the adverse events recorded: gag reflex — 28%, cough — 16.8%, sore throat — 7%, nosebleed — 0.7% (1 patient), vasovagal syncope — 0%. The mean pain score was 18% on the VAS, and only 3.7% regretted having the procedure. ^[1]

In children, Torretta et al. (2013, n=191) and Kubba & Bingham (2001, n=54) recorded no complications of nasal endoscopy, including in children from 2 years of age. ^[2]

II. Situations that require special preparation or a modified technique

1. Coagulopathies and antithrombotic therapy

Nasal endoscopy (without biopsy) is a procedure with minimal bleeding risk. By analogy with flexible bronchoscopy without biopsy, the ACCP (2025) recommends against routine platelet or FFP transfusion before such procedures, even with thrombocytopenia. However, when a biopsy or manipulation of the mucosa is planned, the risk increases: platelets ^[3] <50 × 10⁹/L are associated with a significant increase in bleeding during endoscopic procedures. ^[4][5]

Practical recommendations:

• Diagnostic endoscopy without biopsy — no need to stop anticoagulants/antiplatelet agents or correct the coagulopathy ^[3][6]
• When a biopsy is planned — consider correcting thrombocytopenia to ≥50 × 10⁹/L and individualize the decision to stop anticoagulants ^[4][5]
• In patients with inherited coagulopathies (hemophilia, von Willebrand disease) — prophylactic factor replacement and tranexamic acid for invasive procedures ^[7]

2. Hereditary hemorrhagic telangiectasia (HHT, Rendu-Osler disease)

Nasal endoscopy is not contraindicated in HHT; on the contrary, it is a key diagnostic tool. Matti et al. (2021, n=70 children) performed endoscopy in all patients without complications, and the sensitivity of the Curaçao criteria rose from 28% to 85% when nasal telangiectasias were included. ^[8] Soudry et al. (2025) developed and validated an endoscopic scale for HHT with an ICC of 0.8. ^[9]

Specifics: keep contact between the endoscope and the mucosa to a minimum, avoid suction near telangiectasias, and have means to stop bleeding at hand (packing, cautery).

3. Skull base defects and CSF leak

Diagnostic endoscopy is indicated when a CSF leak is suspected — it can show a pulsating light reflex at the skull base, a meningocele or a meningoencephalocele. However, ^[10] special caution is required:

• Avoid pressure on the area of the defect
• Do not use suction near suspicious areas
• If a defect is confirmed — minimal manipulation until surgical repair because of the risk of ascending infection (meningitis) ^[11][12]

4. Allergy to local anesthetics

True allergy to lidocaine (an amide anesthetic) is extremely rare. The FDA states that allergic reactions to lidocaine are “extremely rare”. Patients allergic to ester anesthetics (procaine, tetracaine, benzocaine) ^[13] have no cross-sensitivity to lidocaine. ^[13]

With a confirmed allergy to amide anesthetics:

• Endoscopy can be performed without anesthesia — a Cochrane review (2011, 8 RCTs) showed that 5 of 8 studies found no advantage of anesthesia over placebo ^[14]
• Use only a decongestant (xylometazoline, oxymetazoline) without an anesthetic
• In children, anesthesia is not required (discomfort VAS ~2/10 without anesthesia) ^[15]

5. Severe nasal obstruction and anatomical anomalies

With marked septal deviation, massive polyposis, choanal atresia or postoperative changes:

• Use a smaller-diameter flexible endoscope (2.2–2.7 mm instead of 4 mm) ^[16]
• Prior decongestion is especially important to widen the nasal passages ^[17]
• If the endoscope cannot be passed through one side — examine through the other nostril
• In rare cases — examination through the oropharynx (transoral nasopharyngeal endoscopy)

6. Active nosebleed

Endoscopy during active epistaxis is not contraindicated; on the contrary, it is recommended by the AAO-HNS (2020) to locate the source of bleeding (successful in 87–93% of cases). However, the following are required: ^[18]

• A prior attempt to stop the bleeding (pressure, packing)
• Suction available for visualization during bleeding
• Readiness for cautery or packing once the source is identified

III. Situations that call for postponing the procedure

IV. Precautions when using topical medications

Lidocaine, the most commonly used anesthetic, requires dose limits to be observed: ^[13]

• Adults: maximum 300 mg or 4.5 mg/kg
• Children: maximum 7 mg/kg (3.2 mg/lb)
• Reduced doses in older and frail patients, and in severe shock or heart block
• Resuscitation equipment must be immediately available
• When a spray is used — risk of aspiration into the lower airways with rapid absorption and high plasma levels

Decongestants (xylometazoline, oxymetazoline, phenylephrine) — with caution in uncontrolled hypertension, severe cardiovascular disease, angle-closure glaucoma and in patients taking MAO inhibitors. ^[17]

V. Summary table: contraindications and special situations

So nasal endoscopy is one of the safest diagnostic procedures in otorhinolaryngology. No absolute contraindications to diagnostic endoscopy without biopsy have been described in the literature; all restrictions are relative and require an individualized approach.