Dialysis Primer Flashcards
What is dialysis?
• Method of filtration w/movement of blood across a semipermeable to remove undesired artifacts
What is dialysis used for?
- Correct fluid/electrolyte imbalances
- Remove waste products in renal failure
- Treat drug overdoses
What are the two types of dialysis?
- Peritoneal dialysis (PD)
* Hemodialysis (HD)
When is dialysis generally initiated?
• When GFR (or creatinine clearance) = <15mL/min
Dialysis uses diffusion and osmosis for filtration.
Diffusion is the movement of fluid from an area of _____ to an area of _____ concentration of solutes.
• greater, lesser
Dialysis uses diffusion and osmosis for filtration.
Osmosis is the movement of fluid from an area of _____ to an area of _____ concentration of solutes.
• lesser, greater
What are some conditions that call for immediate dialysis?
- Uremic complications
- Neuropathies
- Uncontrolled hyperkalemia
- Pericarditis
- Accelerated HTN
What are the components of dialysis?
- Blood
- Semi-permeable membrane
- Dialysate
What is the purpose of dialysate?
• To control filtration gradients of osmosis
The patient preparation for dialysis consists of…
- Emptying the bladder and bowel
- Weighing the patient
- Obtaining a signed consent form.
What is used more often, peritoneal dialysis or hemodialysis?
• Hemodialysis, PD is only used in apprx 12% of pts
What is the basic concept of peritoneal dialysis?
- A dialysis catheter is surgically placed through the abdomen into the peritoneal cavity
- A dialysis solution bag is hung higher than insertion point to drain into peritoneal cavity
- Dialysate draws impurities into the peritoneal cavity
- A drain bag is hung below the insertion point to remove fluids
What is the care for a newly placed PD catheter?
- Site clean to heal (This can be w/ or w/out a dressing pending particulars of the individual)
- Pt is taught to observe for signs of infection
- Site should not be submerged in bathwater
- Once healed, the pt may shower and pat dry
With peritoneal dialysis, what serves as the semi-permeable membrane?
• The peritoneum (lining of the peritoneal cavity)
What is the active component in dialysate that helps control rates of osmosis?
• Glucose
What are the basics to keep in mind re: dialysate for peritoneal dialysis?
- Available in 1 or 2 L plastic bags w/ glucose concentrations of 1.5, 2.5 and 4.25% (3L can be given pending size of pt)
- Electrolyte compositions is similar to plasma
- Solution is warmed to body temperature
What are the 3 phases of the PD cycle?
- Infill
- Dwell
- Drain
Describe the infill phase of PD.
- Prescribed amount of solution infused through established catheter over about 10 minutes
- After solution infused, inflow clamp closed to prevent air from entering tubing
Describe the dwell phase of PD.
- Diffusion and osmosis occur between patient’s blood and peritoneal cavity.
- Duration of time varies, depending on the method.
- 20 – 30 minutes to 8 hours or more
Describe the drain phase of PD.
- Peritoneal fluids are drained over 15 to 30 minutes
* May be facilitated by gently massaging abdomen or changing position
One cycle = one ______.
• Exchange
For manual PD, a period of about __ to __ minutes, minimum, is required to complete an exchange.
• 30 to 50
What is automated peritoneal dialysis?
• An automated mechanical Cycler delivers the dialysate, times and controls fill, dwell, and drain
APD is the most popular form of PD, as it allows patients to accomplish dialysis while they sleep. The machine cycles four or more exchanges per night with __ to __ hours per exchange.
• 1 to 2
