Chronic peripheral lymphatic cannulation in the dog

Peripheral lymph collected acutely has been commonly sampled as representative of non-visceral interstitial fluid. By developing a prenodal lymphatic-lymphatic (L-L) shunt, we were able to collect peripheral lymph for 3-5 days in unanesthetized dogs. The L-L shunt was constructed entirely of medical grade silicone rubber tubing designed with a slip of coupling which allowed the shunt to be disconnected for lymph collection and reconnected at night. Average peripheral lymph flow (4.9 ml/hr leg) in unanesthetized dogs was almost twice the flow rate previously observed in anesthetized dogs. The average lymph/plasma total protein concentration ratio (0.16), however, was similar to that previously found in anesthetized dogs. Lymph protein concentration fell with the collection during the day and became more concentrated at night. Lymph flow did not change greatly during daytime collection. Average peripheral lymph collection volume was greater than 200 ml/dog. The L-L shunt allows collection of prenodal-lymph in experiments where unanesthetized dogs are required (e.g., feeding studies). They also are useful when multiple protocols are conducted on the same dog or when large volumes of peripheral lymph are required.