Renal Flashcards
Which kidney is more cranial?
Right
What is the nephron?
- The structural and functional unit of the kidney
- Each nephron includes a filter, glomerulus, Bowmnan’s capsule, proximal tubule, loop of Henle, and distal tubule
How many nephrons do dogs and cats have?
Dogs: 415,000
Cats:: 190,000
What is the glomerulus?
A capillary bed fed by afferent arterioles that arise from the renal artery. Blood enters, circulates quickly, and exits via efferent arteriole, which continues to supply blood to remainder of nephron and carry away reabsorbed solutes and water from tubules
What is Bowman’s capsule?
A hollow structure that surrounds the glomerulus that is comprised of epithelial cells. Its thin epithelial enables rapid movement of ultrafiltrate into the B/C. Fluids absorbed into the B/C moves into the lumen of the proximal tubules
Where does the loop of Henle go?
- From the cortex to the medulla then back to the cortex
- The distal tubule terminates at the collecting duct
What is urine?
It is what is leftover after the kidneys reabsorb 99% of the plasma water filtered by the tubules
Oliguria is characterized by?
- UOP 0.27-0.5ml/kg/hr
- Low USG (<1.020)
- Indicates the kidney has lost the ability to concentrate urine
Why is it OK to give UO cats IVF that already contain K in them?
These are physiolgoical concentrations of K that don’t affect K clearance and also act as an alkalinizing isotonic solution (most UO pts will be in metabolic acidosis)
What is the most common stone type?
Struvite
- Urine must be saturated with Mg, NH3, Phos for them to form
- Usually associated with urease producing microbes in UTI which alkalinize the urine
- Sx preferred but can be medically managed
What type of stone are Dalmations prone to?
Ammonium urate
- Diet should be purine restricted
- Urine should be alkalinized
How long can a urine sample be refrigerated for?
Up to 8 hours in a sterile container without a substantial change in results
What are the most common uropathogens?
AEROBIC bacteria
- Escherichia
- Staph
- Proteus
- Streptococcus
- Klebsiella
- Entero
- Pseudomonas
Where is peripheral edema usually noticed first?
The hocks
What creates the osmotic gradient required in PD?
Dextrose
What is the most common complication of PD?
Peritonitis
What is Intermittent Hemodialysis?
- Planned treatment
- For patients with CKD that require long term management of uremia
- Typically lasts 3-4 hours and is performed several times a week
- Rates are higher
- Uses principle of diffusion
What is Continuous Renal Replacement Therapy?
- Typically chosen for AKI or toxin exposure
- Tx are longer with slower flow rates designed to mimic native kidney function
- Uses a combo of convection and diffusion
The arterial access catheter carries blood from ___ to ____?
- From the patient to the dialyzer
- Connects to proximal port
The venous access catheter carries blood from ___ to ___?
- From the dialyzer to the patient
- Connects to distal port
Why is sodium citrate beneficial to use?
- Bacteriostatic
- Prevents biofilm
- Cheaper than heparin
What are the four dialysis techniques?
- Ultrafiltration
- Diffusion
- Convection
- Adsorption
What is ultrafiltration?
- Movement of fluid through a semi permeable membrane caused by a pressure gradient
- Leads to removal of “plasma water” from the blood and produces a fluid known as “ultrafiltrate”
What is diffusion?
- The movement of solutes from an area of higher concentration to an area of low concentration
- Useful for smaller molecules
What is convection?
- The movement of solutes with water flow
What is adsorption?
- The adhesion of molecules from a liquid (blood) onto a solid surface (membrane)
What are the four dialysis treatment modes?
- Continuous veno-venous hemofiltration
- Continuous veno-venous hemodialysis
- Continuous veno-venous hemodiafiltration
- Slow continuous ultrafiltration
What is continuous veno-venous hemofiltration (CVVH)?
- Most similar to IHD
- Uses convection
- Used for solute and fluid removal
- Produces ultrafiltrate
- Dialysate NOT used - replacement fluid used to aid convection
What is continuous veno-venous hemodialysis (CVVHD)?
- Similar to IHD
- Uses diffusion (D for hemoDialysis and Diffusion)
- Utilises dialysate - replacement fluids NOT used
What is continuous veno-venous hemodiafiltration (CVVHDF)?
- Combines CVVH and CVVHD
- Solutes are removed by diffusion and convection
- Both replacement fluids and dialysate are used
What is slow continuous ultrafiltration?
- Primarily used for fluid removal
- Not aimed at solute removal
- Resulting fluid is EFFLUENT
What is dialysis disequilibrium syndrome?
- The development of cerebral edema induced by rapid changes in the osmolality of blood
- Directly related to rate
- Occurs in 1st few hours - 48 hours
Which modes are safest for hypoalbuminemic patients
- CRRT & HD
