Bell's palsy

Disclaimer

These guidelines have been produced to guide clinical decision making for the medical, nursing and allied health staff of Perth Children’s Hospital. They are not strict protocols, and they do not replace the judgement of a senior clinician. Clinical common-sense should be applied at all times. These clinical guidelines should never be relied on as a substitute for proper assessment with respect to the particular circumstances of each case and the needs of each patient. Clinicians should also consider the local skill level available and their local area policies before following any guideline. 

Read the full PCH Emergency Department disclaimer.

 

Aim

To guide staff with the assessment and management of Bell's palsy.

Background

Bell’s palsy is characterised by an acute onset of unilateral lower motor neurone facial nerve palsy without detectable underlying cause.1,2 It occurs less frequently in children than adults and it is important to consider other diagnoses to optimise recovery. Management of Bell’s palsy is aimed at achieving complete recovery or reducing the negative sequelae2.

Differential diagnosis

  • Preceding trauma
  • General health/concurrent illness
  • Acute or chronic otitis media
  • Cholesteatoma
  • Mastoiditis/osteomyelitis
  • Herpes Zoster (Ramsay Hunt Syndrome)
  • Rare: congenital/metabolic/genetic/neoplastic.

Assessment

Bell’s palsy is diagnosed by physically examining the child and excluding other causes of facial weakness and paralysis.

Features include:

  • Unilateral lower motor neurone facial nerve palsy
  • Upper respiratory tract infection in previous month
  • Posterior auricular pain in previous days
  • Poor tear clearance due to weakness 
  • Dry eyes
  • Hyperacusis
  • Rapid onset – most patients present within 48 hours.

Assessment and referral pathway

Examination and referral flowchart

House Brackmann facial grading scale2

Grade Definition
1 Normal symmetrical function in all areas 
2 Slight weakness noticeable only on close inspection
Complete eye closure with minimal effort 
3 Obvious weakness but not disfiguring
May not be able to lift eyebrow
Complete eye closure
Strong but asymmetrical mouth movement with maximal effort
4 Obvious disfiguring weakness
Inability to lift brow
Incomplete eye closure and asymmetry of mouth with maximal effort
5 Motion barely perceptible
Incomplete eye closure, slight movement of corner of mouth
6 No movement or loss of tone
Note: Synkenesis (abnormal re-wiring of the nerves when healing) will usually not be a clinical issue in ED. This will develop later in Bell's palsy.

Investigations

  • Swab for PCR and blood for herpes simplex virus (HSV) titres if vesicles are noted
  • Perform full blood picture to exclude haematological malignancy as cause of facial palsy (especially if steroids are to be prescribed).

Management

  • If the patient is less than two years of age and/or the diagnosis of Bell's palsy is uncertain, consider a neurology and/or ENT consult. 
  • Consult with the on call Neurologist regarding use of steroids. 
  • Photographs of the face of the child at initial presentation and on follow up are useful to monitor progress. 
  • Antiviral therapy is usually of no benefit 2,4

Eye protection

  • Patients with incomplete eye closure are at risk of foreign body disposition and corneal ulceration.3,4
  • Eye-protective measures in these patients are imperative. Provide prescription for discharge:
Gel based lubricant for day use 5 Option 1: Viscotears or GelTears (both carbomer 980 0.2%) – QID
Option 2: Genteal Gel (carbomer 980 0.2%, hypromellose 0.3%) or Refresh Liguigel (carmellose 1%) initially QID then reduce to TDS when back at school – for ease of use
Ointment for night use until lid closure is complete  Lacrilube, Poly Visc or Ircal (all paraffin and wool fat) 
Severe lid laxity/redness  Lacrilube, Poly Visc or Ircal (all paraffin and wool fat) QID
Note If eye becomes red (and fails to settle over a few days with increased lubricant) or the palsy is not resolving as expected over 4-6 weeks, then ophthamology should be involved to consider whether a tarsorrhaphy is required. 

Disclaimer: Some of these formulations are not stocked by the PCH Outpatient Pharmacy. The hospital formulary can be viewed on Formulary 1.

Follow up

Review in the Emergency Department in two weeks:

  • If improving – no further follow up
  • If not improving – review history and examination as above and discuss with the on call Neurologist.

References

  1. McCaul JA, Cascarini L, Godden D, Coombes D, Brennan PA, Kerawala CJ. Evidence based management of Bell’s palsy. Br J Oral Maxillofac Surg2014;52(5):387–91.
  2. Phan N, Panizza B, Wallwork B. A General Practice Approach to Bell’s palsy. Australian Family Physician, Neurology 2016; 45 (11) 794-797
  3. Baugh RF, Basura GJ, Ishii LE, et al. Clinical practice guidelines: Bell’s palsy. Otolaryngol Head Neck Surg 2013;149(3 Suppl):S1–27.
  4. De Almeida JR, Guyatt GH, Sud S, et al. Management of Bell palsy: Clinical practice guidelines. CMAJ 2014;186(12):917–22.
  5. MIMS ONLINE. 2019 MIMS Australia

Bibliography

1. Lunan R, Nagarajan L. Bell’s palsy: A guideline proposal following a review of practice. Journal of Paediatrics and Child Health 44 (2008) 219‐220
2. House JW, Brackmann DE. Facial nerve grading system. Orolaryngolgy – Head and Neck Surgery, 1996; 114:380-6

 

Endorsed by:  Director, Emergency Department  Date:  Apr 2020


 Review date:   Mar 2023


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Last reviewed: 21-04-2020
Last updated: 14-09-2020