HD and PD
Card Set Information
HD and PD
In what stage of CKD do you usually start planing for dialysis?
What are factors to consider when deciding if dialysis should be initiated?
: persistent anorexia, N/V, fatigue, pruritis, uncontrolled HTN or CHF, low albumin, neurologic deficits
Fluid balance (fluid overloaded)
Compliance with diet and medications
What is dialysis?
A process that removes substances from blood that cannot be cleared due to decreased renal function
What are some advantages of HD?
Higher soluble clearance --> intermittent use
Low technique failure rate
Closer patient monitoring
What are some diadvantages of HD?
Requires multiple weekly visits to dialysis center
Disequilibrium, hypotension, muscle cramps are common
Vascular access complications
What are som eadvantages of PD?
More hemodynamic stability
Suitable for pt that cannot tolerate HD
Sense of independence (no machine)
What are some disadvantages of PD?
Protein and amino acid loss and decreased appetite --> malnutrition
Catheter malfunction and/or infection
Patient burnout (decreased compliance)
What is convection (aka ultrafiltration)?
Movement of water
The rate depends on hydrostatic pressure gradient across the membrane and dialyzer composition
What is the preferred type of vascular access and why?
Lowest rate of complications
Require at least 2 months to "mature" before use
What is the 2nd line preferrred vascular acess?
How long does it take for an AV graft to endothelialize before use?
Do AV fistulas or grafts last longer?
What type of vascular acess is placed in the subclavian or internal jugular vein?
Cuffed or tunneled venous catheters
Do low-flux or high-flux membranes act similar to the body?
When is heparin administered?
After blood pump and before dialyzer
What is a common HD regimen?
3-4 hrs TIW (MWF or TThS)
What are the two goals of HD?
Achieve dry weight
Adequate removal of endogenous waste products
How can you calculate a dialysis dose?
Urea Reduction Ratio
Urea-reduction ratio only accunts for urea removal via ________
What is the URR calculation?
(Pre BUN- Post BUN)/ Pre BUN x 100
What is the most common complication of HD?
What are some predisposing factors to hypotension?
Target dry weight is too low
Vasodilation with acetate containing buffer solutions
Taking antihypertensive meds pre HD
Eating food before HD
What are some non-pharmacologic preventions of hypotension?
Adjust dry weight
Use bicarbonate buffer solutions
Avoid food before HD
What are the acute treatment options for hypotension?
Trendelenburg position (lay on bed with head below feet to maintain perfusion to the brain)
Decrease ultrafiltrate rate
Give IV fluids
: 100-200 mL bolus of 0.9% NaCl
What are the pharmacologic treatment options for hypotension?
Midodrine 2.5-10 mg PO 30 minutes prior to HD (alpha 1 agonist that causes vasoconstriction; pro drug so it has to be started prior to HD)
What is the possible reason of muscle cramps due to HD?
Plasma volume contraction and decreased muscle perfusion
What are the acute treatment options for muscle cramps?
100-200 ml bolus of 0.9% NaCl
10-20 ml hypertonic soln over 3-5 minutes
50 mL D50-- for non-diabetic patients
What are non-pharmacologic preventative methods for muscle cramps?
Adjust dry weight
What are pharmacologic options for preventing muscle cramps?
Vitamin E 400 IU QHS
Less studied options
: oxazepam, prazosin, hydroquinine
Is thrombosis more common in venous catheters or AV grafts?
What are nonpharmacologic options for treating thrombosis?
Forced saline flush
Exchange of catheter over guidewire
What are two drug options for thrombosis?
What is the most pre-dominant bacteria that causes infections related to HD?
What should you do if a patient experiences a fever during HD?
Culture blood immediately
How should you treated an infection of a tunneled cuffed catheter that has no drainage?
How should you treated an infection of a tunneled cuffed catheter that has drainage?
Systemic gram-positive coverage
How should you treated an infection of a tunneled cuffed catheter that is bactermic with or without systemic symptoms?
Gram positive coverage
If a patient is symptomatic, how long should you wait before removing the catheter?
If patient does not experience symptoms of infection what should be done?
Change catheter and give culture-specific antibiotics for a minimum of 3 weeks
In a local AV graft infection how long should a patient be treated?
Narrow antibiotics once cultures returned for 2-4 weeks
In an extensive AV graft infection how long should a patient be treated with antibiotics?
Narrow once cultures return and treat for 2-4 weeks
Total resection of graft
What type of infection should be treated like bacterial endocarditis? How long should the patient be on antibiotics?
What are symptoms of a Type B reaction to HD?
In a Type A dialyzer reaction, a patient has a hypersensitivity to what?
When does a Type A reaction typically happen?
Usually on initial exposure
What drug can cause a Type A interaction with a bioincompatible or high-flux membrane?
In PD which compartment is filled with dialysate?
What are 4 differences between PD and HD?
No intimate contact btwn dialysate and blood
No countercurrent flow
No way to control blood flow rates
What types of peritoneal access are available?
Permanent indwelling catheter
: 40-45 cm with 20-22 cm in peritoneal cavity
Tunneled inside abdominal cavity
: cuffs provide mechanical support and stability to the catheter
What does the dialysate in PD contain?
: dextrose in hyperosmolar concentrations (induces ultrafiltration) or icodextrin a starch-derived glucose polymer (alternative to dextrose)
Describe the procedure of CAPD
1-3 L of dialysate flows into peritoneal cavity under gravity over around 15 minutes
Dwells in peritoneal cavity for 4-6 hours
Replace with fresh dialysate
Repeated 3-4 times a day (usually single exchange with higher dextrose solution over night)
What type of patients should use APD?
For patients unable or unwilling to perform aseptic technique to catheter
Describe the procedure for APD
Device set up in evening and catheter attached at bedtime
Nocturnal intermittent PD (NIPD)
Continuous cycling peritoneal dialysis (CCPD)
Nocturnal tidal PD (NTPD)
What is the Kt/Vd goal for PD?
What is the total weekly CrCl?
> 60 L/week/1.73 m
What are two mechanical complications of PD?
Kinking of catheter
List the complications of PD
Exacerbation of DM
What percentage of glucose from the dialysate is absorbed during each exchange?
What are some symptoms of PD?
Fever and chills
What are two signs of peritonitis?
WBC > 100 cells with at least 50% neutrophils
What is the incidence of peritonitis?
1 episode every 24 months
What is the most common bacteria that causes peritonitis?
What is the preferred route of administration for peritonitis?
What are the options for gram + coverage?
First generation cephalosporin or vancomycin
What are the options for gram - coverage?
Third generation cephalosporin or aminoglycoside
What is the treatment duration for peritonitis?
14-21 days depending on organism
What type of filtration is Continuous venovenous hemofiltration?
What type of filtration is Continuous venovenous hemodialysis?
What type of filtration is Continuous venovenous hemodiafiltration?
Combines HD and hemofiltration (convection)