THORACIC DUCT INJURY IN NECK DISSECTIONDR AJAY MANICKAMFELLOW , DEPT OF HEAD AND NECK SURGICAL ONCOLOGYTATA MEDICAL CENTRE, KOLKATA

THE THORACIC DUCT•Body’s largest Lymphatic conduit•Draining upwards about 75% of

lymphatic fluid - nearly 2-4 L Lymphatic fluid/day•Cisterna Chyli – Lt Jugulovenous angle.•40-60%

Normal Anatomy• Cisterna chyli (T12-L2)• Rt – Lt (T5-T6)

Clinically Relevant variations

Thoracic duct Embryology• Lymphatic system – 6th week of life – Haemangioblastic stem

cells.• Lymph node formation – 9th week of life• Concurrent regression of previously formed plexus. • One duct remains – drains lymphatics of lower body, Lt Head,

Lt Arm – LT Jugular Subclavian axis. • Lower 2/3rd thoracic duct – Rt embryonic duct• Upper 1/3rd thoracic duct – Lt embryonic duct

Thoracic duct disruption and Injury• 1) Direct Trauma and Laceration of the Thoracic Duct• 2) Occlusion of the Thoracic duct with concurrent leaky

collaterals.

Intra operative assesment• Chyle flow/ second – couple of drops• Cernea et al – Manual Abdominal Compression

Maneuver allowed visualization of thoracic duct leak at the end of nec dissection involving level 4. • Pharyngo esohageal resection and reconstruction, post

op salivary leaks may mimic chyle leak. • Oral methylene blue administration

15 mins – stain in neck – salivaChyle – 1-4hours later

Chylous fistula management after neck dissection• Incidence – 0.62% - 6.2% ( Corrado C Campisi et al)• Incidence was more with B/L Neck dissection• No specific universal international treatment guidelines

Non surgical management

Surgical management

Non surgical management•Nutritional approaches• Somatostatin analogs - octreotide•Negative pressure wound therapy

Nutritional approaches• Aim – Decrease the production and flow of

Lymph – Preventing malnutrition (1900-2000 kcal/day & 100gm protein in diet/ according to body wt)• LFD ( Low Fat Diet) / FFD ( Fat Free Diet)• Enteral nutrition with specialized formula• Parenteral support without oral intake

Problems • How much fat is acceptable to promote closure??• Essential fatty acids, multivitamins, minerals –

nutritional status - may need to be added • MCT ( Medium chain Triglycerides) - transported

via portal vein.• But studies also show – increased output

drainage – with MCT

Literature suggestions (Stager et al, Jensen et al, Benedix et al)• Output - <0.5L/day – low fat, semi elemental

formula• Output - >0.5L/day – elemental formula• Output - >1L/day – TPN > LFD• Intravenous lipid emulsions – IVLE – source of

calories / EFA – bypass chyle flow – not contribute to chyle flow

Somatostatin analogs (Coskun et al, Barilli e al)

•Octreotide – act on endorine and paracrine pathway•Minimize excretion of lymphatic products

Negative pressure wound therapy(Kadota et al)•Low pressure 50mmHg – to avoid an unwanted increase in drainage. •Mainly used in low output fistulas complex poor healing wounds.

SURGICAL MANAGEMENT• Output greater than 1 L - high output• Larygectomized pt with leak more than 5 days –

surgery needed (Stager et al)• Cerfolio et al recommends – ‘fatty meal test’ – if

output remains low from chyle leak for 2 days after the meal, tube can be removed. If the output increases or persists after the fatty meal – surgical intervention

Thoracic duct ligation (Ilczyszyn et al)•Open thoracotomy/ Thoracoscopic

approach• Rt sided approach – occlusion of

thoracic duct by mass ligation of tissue above the supra diaphragmatic hiatus between the azygos vein and the aorta.

Therapeutic Lymphography• Alenjandre Lafront et al – Therapeutic

aplication using a contrast solution of lidocaine and 5ml of methylene blue dye and lipiodol to occlude lymphatic leaks.• Lipiodol – irrigating and inflammatory

effect at the leakage site.

Locoregional flaps (Cernea et al)

•Myofascial flaps – pectoralis major / clavicular head of the sternocleidomastoid muscle.

Lymphatic venous anastomosis•Healthy appearing lymphatic found at the site of surgical incision are selected and directly introduced into the cut end of a recipient vein (external/internal jugular vein) by a U stitch

Thoracic duct embolization - Pedal Lymphangiography• Magnetic resonance ductography - embolization planning• T2 weighed images are obtained in axial and coronal images. • Location of cisterna chyli and configuration of thoracic duct

Intra nodal lymphangiography

Success rates•79%• Success rates higher with traumatic

cases

(N Butyl – 2 – cyanoacrylate) Tissue glue in thoracic duct injury during Neck dissection• Area dried with guaze , chloramphenicol 1%

eye ointment was applied to Internal Jugular vein, carotid artery and vagus nerve • Maximum of 1 ml solution was applied over

the suspected area using sterile applicator. (Blythe et al British Journal of OMFS)

Conclusion • Conservative measures • Management depends on individual case• Functional repair of the thoracic duct injury

should be preferred solution rather than an approach that oblitertes the thoracic duct – lymphatic – chylous pathway, as this can cause unwanted consequences – redistribution of flow - distal complications

References