Popliteal sinus venipuncture in anurans.

Objective: To demonstrate an underutilized, reliable, and technically simple anuran venipuncture technique by use of the popliteal sinus.

Animals: Medium to large (> 30 g) anuran species.

Methods: The animal is manually restrained using an encircling grip around the pelvic girdle. With the ventrum facing the phlebotomist, the phlebotomist grasps the distal hind limb and gently extends it. If necessary, the medial stifle can be rinsed with sterile water or saline to remove gross debris. Using a caudomedial approach, a 25- to 27-G, 0.5-inch (1.27-cm) needle and attached syringe is advanced toward the stifle at an approximately 45° angle while maintaining negative pressure. If lymphatic fluid or a visibly lymphatic fluid-contaminated blood sample is obtained, the sample is discarded and the attempt is repeated with a new needle and syringe. Collection volume should not exceed 1% of body weight in systemically healthy animals. In compromised animals, a reduction in collection volume should be considered (eg, ≤ 0.5% of body weight). While the phlebotomist may have an ergonomic preference, either hind limb can be used for blood collection.

Results: Popliteal sinus venipuncture in anurans can be safely and easily performed with only manual restraint.

Clinical relevance: Commonly utilized anuran blood collection techniques include venipuncture of the ventral abdominal vein and lingual venous plexus and cardiocentesis. These techniques can be technically difficult and may pose risks to the patient, particularly if attempted without chemical restraint. Popliteal sinus venipuncture is a reliable, technically simple alternative blood collection technique that can be safely performed in anurans with only manual restraint.