Cardiothoracic Surgery: Chylothorax

Chylothorax

Definition

  • Definition: Chyle Leakage into the Pleural Cavity
  • Output Level:
    • Low Output: < 1 L Chyle Per Day
    • High Output: > 1 L Chyle Per Day

Causes

  • Traumatic (50%):
    • Iatrogenic
      • Esophageal Perforation from Nasogastric Tube
      • Esophagectomy
      • Pulmonary Resection
      • Heart Transplant
    • Penetrating or Blunt Trauma
    • Straining
  • Non-Traumatic (50%):
    • Malignancy (Lymphoma) – Most Common Non-Traumatic Cause
    • Idiopathic
    • Pleuritis
    • Cirrhosis
    • Nephrosis
    • Sarcoidosis
    • Subclavian Vein Thrombosis
    • Superior Vena Cava Syndrome
    • Infectious Lymphadenitis
    • Tuberculosis
    • Filariasis

Presentation

  • Symptoms:
    • Dyspnea
    • Chest Heaviness
    • Fatigue
    • Weight Loss
    • Chest Pain is Rare – Chyme Does Not Cause Inflammation
  • Increased Output After Oral Intake
  • Classically Milky-White Fluid (50%)
    • Can Be Bloody or Yellow-Turbid – May Turn More Milky After a High-Fat Meal
  • Resistant to Infection

Diagnosis

  • Diagnosis: Imaging (CT/CXR) & Thoracentesis
  • Thoracentesis Fluid Analysis:
    • Triglycerides:
      • Level > 110 mg/dL – Diagnostic
      • Levels 50-110 mg/dL – Inconclusive
        • Should Prompt Lipoprotein Electrophoresis (Evaluate for Chylomicrons)
      • Levels < 50 mg/dL – Rules Out Chylothorax
    • Sudan Stain Positive for Chylomicrons
  • Other Fluid Findings:
    • Milky-White Color
    • Increased WBC
    • Low LDH

Chyle 1

Treatment

  • Initial Treatment: Conservative Management & Treatment of Underlying Condition
    • Dietary Modification (High Protein, Low Fat & Supplement Medium-Chain Fatty Acids)
      • Long-Chains Absorb into Lymphatics
      • Medium-Chains Absorb Directly into Portal System
        • Reduce Production & Flow of Chyle
    • Chest Tube if Symptomatic
    • Octreotide (Somatostatin Analog) Decreases Chyle Production
  • If Fails (> 1-2 Weeks): Thoracic Duct Ligation
    • Surgery:
      • Done by Video-Assisted Thoracoscopic Surgery (VATS)
      • Approach: Right Side (Regardless of Injured Side)
        • Larger, Easier to Find, Closer to Origin & Stops Flow from Accessory Ducts
      • Consider with/without Pleurodesis
    • Consider Percutaneous Thoracic Duct Embolization if Poor Surgical Candidate
    • Consider Early Intervention (< 1-5 Days) if High Output

Fatty Acid Absorption; Long-Chain (LCTG) Absorbed into Lymphatic Circulation in Chylomicrons, Medium-Chain (MCTG) Absorbed into Portal Circulation 2

References

  1. Matani S, Pierce JR Jr. Spilt Milk: An Unusual Cause of Bilateral Chylothorax. J Investig Med High Impact Case Rep. 2015 Apr 22;3(2):2324709615583877. (License: CC BY-3.0)
  2. El Mouzan MI. Chronic diarrhea in children: part I. Physiology, pathophysiology, etiology. Saudi J Gastroenterol. 1995 Jan;1(1):37-42.(License: CC BY-NC-SA-4.0)