Glomerular filtration rates of naturally cold-stunned Kemp's ridley turtles (Lepidochelys kempii): comparison of initial vs. convalescent values

Iohexol clearance testing was used to determine glomerular filtration rates (GFR) for 12 juvenile Kemp's ridley turtles (Lepidochelys kempii) that stranded because of cold-stunning. Iohexol was injected intravenously at 75 mg/kg, with subsequent plasma collection at 4, 8, and 24 h post-injection for measurement of iohexol iodine concentrations by inductively coupled plasma mass spectrometry (ICP-MS). Initial GFR was determined on median day 4 of hospitalization (range day 2–5) at an average body temperature of 19°C (66°F) (range 18–21°C [64–70°F]). Mean initial GFR was 4.6 mL/kg/h (range 1.9–8.7 mL/kg/h, n = 10). Convalescent GFR was determined on median day 126 of hospitalization (range day 108–232) at an average body temperature of 24°C (75°F) (range 23–25°C [74–77°F]). Mean convalescent GFR was 13.5 mL/kg/h (range 8.5–21.5 mL/kg/h, n = 10). Statistical analysis of paired initial and convalescent data demonstrated a significantly lower initial GFR, body weight, straight carapace length, and bod...