-Used to correct fluid and electrolyte imbalances and remove waste products
-Big nutrition change: patient can have more protein!
-Generally dialysis is initiated when the pt uremia can no longer be adequately managed conservatively or when GFR is less than 15 mL/min. -Certain uremic complications including encephalopathy, neuropathies, uncontrolled hyperkalemia, pericarditis and accelerated HTN indicate a need for immediate dialysis
Types of Dialysis
-Three types of dialysis:
1. Hemodialysis (HD)
2. Peritoneal (PD)
3. Continuous renal replacement therapy (CRRT)
Perotoneal Dialysis (PD) - Advantages
-Immediate initiation in almost any hospital
-Less complicated than HD
-Portable system with CAPD
-Fewer dietary restrictions
-Relatively short training time
-Usable in the patient with vascular access problems
-Less cardiovascular stress
-Home dialysis possible
-Preferable for the diabetic patient
Perotoneal Dialysis (PD) - Disadvantages
-Bacterial or chemical peritonitis **Biggest downside to PD**
-Protein loss into dialysate
-Exit site and tunnel infections
-Self-image problems with catheter placement
-Surgery for catheter placement
-Contraindicated in the pt. with multiple abdominal surgeries, trauma, unrepaired hernia
-Specially trained personnel needed
-Catheter can migrate
Hemodialysis (HD) - Disadvantages
-Vascular access problem
-Dietary and fluid restrictions
-Heparinization may be necessary
-Extensive equipment necessary
-Hypotension during dialysis
-Added blood loss that contributes to anemia
-Specially trained personnel necessary
-Surgery for permanent access placement
-Self-image problems with permanent access
Hemodialysis (HD) - Advantages
-Rapid fluid removal
-Rapid removal of urea and creatinine
-Effective K removal
-Less protein loss
-Lowering of serum triglycerides
-Home dialysis possible
-Temporary access can be placed at bedside
Dialysis Solutions and Cycles
Access: Tenckhoff catheter
-Silicone rubber tubing with tip in peritoneal cavity
-Need to wait before dialysis can be started (7-14 days)
-Daily tube care is needed (application of aseptic solution and a clean dressing)
-Comercially prepared bags (1 or 2 L) with glucose concentrations 1.5%, 2.5% and 4.25%. Electrolyte concentration is similar to that of plasma.
-Using dry heat the soluition is warms up to body temperature to increase peritoneal clearance, prevent hypothermia and the enhance comfort.
3 Phases of PD aka Exchange
-Patient dialyzing at home may require 4 exchanges/day
-Patient in hospital may require 12 - 24 exchanges/day
1. Inflow (fill)
-Prescribed amount of solution is infused over 10 min
-Usually about 2 L
-Rate may be decreased if pt is in pain
-After the solution has infused, the inflow clamp is closed to prevent air from entering the tubing
2. Dwell (equilibration)-Diffusion and osmosis occurs
-Dwell time can range from 20 min to over 8 hours
3. Drain-Fluid is removed from the peritoneal cavity
-Takes 15-30 min
2 Methods of PD
1. Automated Peritoneal Dialysis
2. Continuous Ambulatory Peritoneal Dialysis
Continuous Ambulatory PD
-At least 4 exchanges per day
-Dwell time is 4-10 hours
-Disconnect the tubing between catheter and bag during dwell time to decrease risk for peritonitis.
-Drainage occurs by gravity
-Massage abd. gently or turn side to side to facilitate drainage
Contraindications for PD
1. Hx of multiple abdominal surgical procedures or chronic abdominal pathologic conditions (pancreatitis, diverticulitis)
2. Recurrent abdominal wall or inguinal hernias
3. Obesity with large abdominal wall and fat deposits
4. Preexisting vertebral disease (chronic back problems)
5. Severe obstructive pulmonary disease
-Machine controls all 3 phases
-Cycles for more exchanges than manual
-Disconnected in the AM, but fluid from last exchange is often left in the abd throughout the day
-Can be used in conjunction with ambulatory PD
Prevention of Infection during PD
ASEPTIC TECHNIQUE WHILE CONNECTING AND DISCONNECTING TUBING!!
Complications of PD
-Exit Site Infection: most commonly caused by staphylococcus aureus or S. epidermidis. Monitor for redness, tenderness and drainage.
-Peritonitis: Cloudy peritoneal effluent. Effluent WBC's over 100 with increased neutrophils. Abd pain and distention. N/V. Hyperactive BS. Culture effluent for diagnosis.
-Abdominal pain: Common complication. Slowing down infusion rate can often correct the problem.
-Outflow problems: If outflow is less than 80% of inflow check for a kink in the tubing. Sometimes evacuation of the bowel will correct the outflow decrease.
-Increased abd pressure: R/T hernias or lower back problems
-Bleeding: Effluent drainage after the first few exchanges may be pink or slightly bloody this is normal. If there is bloody effluent over several days or new apperance of blood it may indicate intraperitoneal bleeding.
-Pulmonary Complications: Atelectasis, pnemonia, and bronchitis may occur from upward displacement of the diaphragm decreasing lung expansion. HOB elevated and positioning may help.
-Protein loss: The periotoneal membrane is permeable to plasma proteins, amino acids and polypeptides. Can lose as much as 5-15g.daywhile on dialysis
-CHO & Lipid abnormalities: Dialysate glucose is absorbed via the peritoneum and may be as much as 100-150g/day. This causes increase in insulin production which stimulates the liver to excrete triglycerides.
-Encapsulating Sclerosing Peritonitis and loss of utrafiltration: the development of a thick fibrous membrane that surrounds and compresses the bowel for unknown reasons.