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Pharynx: ventral pharyngotomy

ISSN 2398-2977


Introduction

  • Surgical access to the oropharynx is limited and the technique of ventral pharyngotomy has been reported as an alternative to ventral laryngotomy   Larynx: ventral laryngotomy  or oral approaches.

Uses

Advantages

  • Provides direct access to subepiglottic area.

Disadvantages

  • Deep incision with limited visibility.

Alternative techniques

  • Ventral laryngotomy   Larynx: ventral laryngotomy  .
  • Oral approach.
  • Mandibular symphysiotomy - cleft palate surgery.
  • Transendoscopic laser surgery - epiglottic surgery.

Time required

Preparation

  • Aseptic skin preparation: 10 min.
  • General anesthesia (GA): induction and maintenance: 20 min.

Procedure

  • Access to oropharynx: 10-15 min.

Decision taking

Criteria for choosing test

  • Other surgical approaches are more commonly used although direct access to subepiglottic area can be useful in cyst dissection.

Risk assessment

  • Post-operative upper respiratory tract obstruction.

Requirements

Materials required

Minimum equipment

  • Standard surgical pack.

Ideal equipment

  • Self-retaining retractors, eg Weitlaners.

Minimum consumables

  • 2-0 absorbable suture material for blood vessel ligation.

Preparation

Pre-medication

Dietary preparation

  • Standard dietary modification.

Site preparation

Site
  • Ventral aspect of pharynx, caudal mandible and cranial cervical area.
    Preparation
  • Standard aseptic preparation (clean, clip, swab and drape).

Other preparation

Restraint

Technique

Approach

Step 1 - Incision

  • Make a ventral midline longitudinal skin incision rostral to body of thyroid cartilage (rostral to ventral laryngotomy site   Larynx: ventral laryngotomy  ).

Core procedure

 

Step 1 - Expose omohyoid muscles

 
  • Bluntly dissect between sternohyoid muscles to expose the deeper omohyoid muscles.
  • Separate omohyoid muscles axially.

Step 2 - Incise thyrohyoid ligament

 
  • Continue incision line through thyrohyoid ligament.

Step 3 - Enter oropharynx

 
  • Divide hyoepiglottic muscle on midline deep within incision to reveal glossoepiglottic fold.
  • Incise through glossoepiglottic fold.
  • Enter oropharynx.

Step 4 - Additional exposure

 
  • Additional exposure can be achieved:
    EitherBy the use of self-retaining retractors   Retractors: self-retaining - Weislander  .
    OrDivision of the basihyoid bone if cleft palate repair   Hard / soft palate: cleft - surgery  is being attempted.

Exit

 

Step 1 - Wound closure

 
  • The pharyngotomy incision is usually left to heal by secondary intention.

Aftercare

Immediate Aftercare

General Care

  • Close observation for 48 h for normal movement of air through upper respiratory tract.
  • Some self-limiting epistaxis may occur on recovery.

Antimicrobial therapy

  • Not routinely administered.

Special precautions

Potential complications

  • Infection of surgical site (cellulitis or abscess) in first 5-7 days.
  • Discharge from pharyngotomy wound - regular cleaning required and rub barrier cream into surrounding skin, eg petroleum jelly, udder cream.
  • Pharyngeal swelling with respiratory obstruction or dysphagia.

Long term Aftercare

Follow up

  • Wound should heal in 10-21 days.
  • Other action depends upon primary reason for surgery.

Outcomes

Complications

  • Rare.

Prognosis

Further Reading

Publications

Refereed papers