OSSEOUS-VENOUS AND CENTRAL CIRCULATORY TRANSIT TIMES OF TC-99M PERTECHNETATE IN ANESTHETIZED RAPTORS FOLLOWING INTRAOSSEOUS ADMINISTRATION

Intraosseous fluid administration has been proposed as a rapid and eff icient means of delivery of parenteral fluids and pharmaceuticals in c ritically ill birds. Distribution of a radiopharmaceutical was used to evaluate this route of administration in wild birds further. Three re d-tailed hawks (Buteo jamaicensis) and three great horned owls (Bubo v irginianus) were anesthetized and the ulnar marrow cavity was catheter ized with a 20-gauge spinal needle. Seventy-four MBq (2 mCi) of techne tium-99m sodium pertechnetate ((99)mTCO(4)-) were injected into the ul nar marrow cavity with simultaneous acquisition of a dynamic flow stud y using a gamma camera and dedicated nuclear medicine computer. Five r egions of interest (ROI's) were created for each bird. Five of the six acquisitions were successful. The osseous venous transit time (time f rom radionuclide injection in the ulna to the appearance of activity i n the ulnar vein) varied between 0.5 and 2.5 sec. The time when initia l activity appeared in the ulnar vein and subsequently appeared in hea rt/lungs, kidneys, and cloaca varied from 0.5 to 1.5 sec. The time whe n initial activity appeared in the heart/lung region and subsequently appeared in the kidneys varied from 1.5 to 4.0 sec. The time of initia l activity in the kidneys and subsequent activity appearance in the cl oaca varied from 0.0 to 2.5 sec. Uptake in one bird was less than 0.5 sec, but this may have been artifact due to operator error.