Changes in renal function during acute spinal cord injury: Implications for pharmacotherapy

Abstract

Study design:Laboratory investigation in rats submitted to experimental spinal cord injury (SCI).Objective:To characterize changes in renal function during acute SCI.Methods:Sprague Dawley rats were subjected to severe spinal cord contusion at T8 level or to laminectomy as control. Twenty-four hours after spine surgery, clearance assessments of a single dose of iohexol (120 mg kg-1) or of p-aminohippuric acid (PAH, 100 mg kg-1) were used to evaluate glomerular filtration rate (GFR) and tubular secretion (TS), respectively. Blood sampling was used to determine concentrations of both compounds by high-performance liquid chromatography for pharmacokinetic measurements.Results:Iohexol clearance decreased significantly after injury, which resulted in increased concentrations and half-life of iohexol in blood; PAH clearance remained unchanged.Conclusion:GFR but not TS is altered during spinal shock. These observations should be of interest to professionals caring for early cord-injured patients, in order to prevent toxicity and therapeutic failure when administering drugs eliminated by the kidney. © 2013 International Spinal Cord Society. All rights reserved.