PHARYNGOCUTANEOUS FISTULA

Short Note 2005

-A fistula is an abnormal communication between two epithelialized surfaces.

-Pharyngocutaneous fistula is the most common non-fatal complication following total laryngectomy.

– It creates a communication between the pharynx and cervical skin around the surgical incision or, less frequently, the stoma of the tracheostomy.

– Billroth was also the first person to report PCF as one of the complications of total laryngectomy (he performed first total laryngectomy)

– INCIDENCE reported extremely variable ranging from 3.6% to 65%

 

CAUSE:
-Total laryngectomy w or w/o pharyngectomy
-Partial laryngectomy
-Commando procedure

 

PRESENTATION:

-a complication that appears in the early post-operative period after total laryngectomy.

-Usually around 3th to 8th post operative day.

-Pharyngeal contents, usually saliva, flow through the fistula emerging from the cutaneous orifice

– Mean hospitalization time is usually 13 – 15 days in comparison to 3 – 5 days for other patients.

-increased morbidity, delay in adjuvant treatment, prolonged hospitalization, and high treatment costs

-More common in males than females

 

CONTRIBUTING FACTORS:

  1. Time of oral feeding Initiating oral feeding within 48 hours of total laryngectomy without partial pharyngectomy; who have not had a previous surgical resection of the upper aerodigestive tract; and who have either not received previous therapeutic irradiation to the head and neck region; does not increase the frequency of PCF. Oral feeding especially with solid food encourages granulation tissue formation along the fistula tract and eventually results in more spontaneous closure of the fistula tract.
  2. Age – > 60 yrs more predisposed.
  3. Gastroesophageal reflux disease(GORD) Prophylactic use of ranitidine (H2 receptor blocker) and metoclopramide (prokinetic) has decreased the incidence of pharyngo-cutaneous fistula
  4. Preoperative tracheostomy contributes to post total laryngectomy PCF fistula formation
  5. Tumor stage and laryngeal site Glottis Ca > Supraglottis > Pyriform sinus > Subglottis
  6. Preoperative Hb:  Low preoperative Hb increases the incidence of PCF nine-fold
  7.  Preoperative radiation: Related to increase of the radiation field size, dose increment and a change from continuous to fractionated radiation therapy 8. Malnutrition
  8. Suture material: There is a statistically significant difference in the formation of PCF between vicryl and catgut groups in favor of vicryl which has greater tensile strength, less inflammatory reaction and has a longer half- life Staples have shown a much lesser incidence of PCF
  9. Positive surgical margins: Presence of infiltrated margins may explain the higher frequency of fistula formation as a result of deficient healing process occurring at the surgical wound, where the presence of the tumor cells may negatively influence the healing process and wound closure. 11. Vascular diseases related to smoking and alcohol drinking

 

Early diagnosis is important:
Less risky for sepsis and major vessel rupture
More conservative and easy management
Early sign of impending Pharyngocutaneous fistula:
Persistent low-grade fever: 38.5C
wound erythema and edema
localized tenderness in central neck near the wound
wound infection unresponding to conservative treatment
saliva seen at wound or in the drain tube
esophagogram: sinus tract> 2 cm
barium methyl blue swallowing test (+)
definitive fistula formation
Conservative management:
Residual tumor should be excluded firstly
Surgical intervention is reserved when failed by Conservative management
Methods:
Drainage:
Saliva accumulation ->abscess formation ->flap necrosis and sepsis
Goal: infection control and prevention of large fistula
If suction drain tube (+), delay removal or shift to penrose for drainage
If no drain tube:
Small: Repeated aspiration
Large with abscess formation: open drain:
Away from the stoma: prevention of aspiration
Temporal pharyngostoma-> secondary reconstruction
Silicone septal button with stoma bag (khan 1993)
Removal and curettage of necrotic tissue
Pressure dressing for flap down
Tube feeding with adequate nutrition
Infection control: systemic antibiotics: aerobic and anaerobic.
Time: small fistula without infection< 2-3 weeks
Most: less than 40 days
Surgical management:

PCF have been classified according to source of tissue used in reconstruction to three types:
Type I: two layers are repaired locally
Type II: one locally, one distantly
Type III: both layers repaired distantly
Surgical options:
Direct primary closure: 2 layer: inner mucosa and outer skin
Reconstruction methods with local flap and free flap
Local adjacent flap:
Myocutaneous flaps

The pectoralis major flap offers the benefit of an excellent vascular pedicle.

The latissimus dorsi and the trapezius flaps much less advantageous than the versatile, durable pectoralis major.

Muscle flaps Sternocleidomastoid muscle flap is also used for fistula closure which has advantages of workable mass, good coverage and single stage reconstruction.
Free flap:
Forearm flap
Jejunal free graft