Wednesday, February 18, 2015

Taxa de filtração glomerular, débito urinário e taxa de clearance de eletrólitos e sua associação com a sobrevida em cães apresentando lesão renal aguda - Glomerular Filtration Rate, Urine Production, and Fractional Clearance of Electrolytes in Acute Kidney Injury in Dogs and Their Association with Survival

Glomerular Filtration Rate, Urine Production, and Fractional Clearance of Electrolytes in Acute Kidney Injury in Dogs and Their Association with Survival

  1. N. Brown1,†,*
  2. G. Segev2,†
  3. T. Francey3
  4. P. Kass4 and
  5. L.D. Cowgill5
Article first published online: 16 JAN 2015
DOI: 10.1111/jvim.12518
Journal of Veterinary Internal Medicine

Journal of Veterinary Internal Medicine

Volume 29Issue 1pages 28–34January 2015
Total views since publication: 0
Article has an altmetric score of 3


Keywords:

  • Acute renal failure;
  • Kidney;
  • Renal/Urinary tract;
  • Excretion ratio;
  • Urinary clearance;
  • Prognostic indicators

Background

Acute kidney injury (AKI) is common in dogs. Few studies have assessed sequential changes in indices of kidney function in dogs with naturally occurring AKI.

Objective

To document sequential changes of conventional indices of renal function, to better define the course of AKI, and to identify a candidate marker for recovery.

Animals

Ten dogs with AKI.

Methods

Dogs were prospectively enrolled and divided into surviving and nonsurviving dogs. Urine production was measured with a closed system for 7 days. One and 24-hour urinary clearances were performed daily to estimate solute excretion and glomerular filtration rate (GFR). Solute excretion was calculated as an excretion ratio (ER) and fractional clearance (FC) based on both the 1- and 24-hour urine collections.

Results

Four dogs survived and 6 died. At presentation, GFR was not significantly different between the outcome groups, but significantly (P = .03) increased over time in the surviving, but not in the nonsurviving dogs. Fractional clearance of Na decreased significantly over time (20.2–9.4%, P < .0001) in the surviving, but not in the nonsurviving dogs. The ER and FC of solutes were highly correlated (r, 0.70–0.95).

Conclusion and Clinical Impact

Excretion ratio might be used in the clinical setting as a surrogate marker to follow trends in solute excretion. Increased GFR, urine production, and decreased FC of Na were markers of renal recovery. The FC of Na is a simple, noninvasive, and cost-effective method that can be used to evaluate recovery of renal function.