RENAL REPLACEMENT THERAPIES PURPOSES OF DIALYSIS 1. Removes excess fluids and waste products. 2. Restores chemical and electrolyte balance HEMODIALYSIS one of several renal replacement therapies used for the treatment of renal failure. HD involves the extracorporeal (outside of the body) passage of the clients blood through a semi permeable membrane that serves as an artificial kidney.
CLIENT SELECTION GENERAL GUIDELINE REQUIREMENTS FOR APPROPRIATE CLIENT SELECTION 1. Presence of fatal, irreversible renal failure when other therapies are unacceptable or ineffective. 2. Absence of illnesses that would prevent or seriously complicate HD. 3. Expectation of rehabilitation. 4. The clients acceptance of the regimen.
Components of Hemodialysis Dialyzer or artificial kidney Dialyzer has 4 components: Blood compartment, Dialysate compartment, Semipermeable membrane, enclosed structure to support the membrane. Dialysate – made up of clear H2O & chemicals. Compositions may be altered accdg to pts needs for treatment of electrolyte imbalance. Warmed to 37.8 C = to 100 F to increase efficiency of diffusion. Prevent decrease in pts blood temperature. Vascular access routes – AV fistula, AV Graft, Dual Lumen Cathater, AV Shunt. Hemodialysis machine -
PROCEDURE The principles of HD are based on the passive transfer of toxins, which is accomplished by diffusion. When HD is initiated, blood and dialysate flow in opposite directions from their respective sides of an enclosed semi permeable membrane. The dialysate is a balanced mix of electrolytes and water that closely resembles human plasma. On the other side of the membrane is the clients blood, which contains metabolic waste products, excess water, and excess electrolytes. During HD, the waste products move from the blood into the dialysate because of the difference in their concentrations (diffusion). Excess water is also removed from the blood into the dialysate (osmosis). Electrolytes can move in either direction, as needed, and take some fluid with them. Potassium and sodium typically move out of the plasma. This process continues as the blood and the dialysate are circulated past the membrane for a preset length of time. Duration and frequency of HD tx depend on the amt of metabolic waste to be cleared, and the amt of fluid to be removed.
COMPLICATIONS OF HEMODIALYSIS Dialysis disequilibrium syndrome- the cause is unknown but maybe due to rapid decrease in blood urea nitrogen levels during HD. These change can cause cerebral edema- leads to increase intracranial pressure. Infection- transmitted by blood transfusion are another serious complication associated with long term HD. Hepatitis Infection- in clients with chronic renal failure.
Best Practice for Caring for the client Undergoing Hemodialysis Weigh the client before and after dialysis. Know the clients dry weight. Discuss with physician whether any of the clients medications should be withheld until after dialysis. Be aware of events that occurred during the dialysis treatment. Measure blood pressure, pulse rate, respirations, and temp. Assess for symptoms of orthostatic hypotension. Assess the vascular access site. Observe for bleeding Assess the clients level of consciousness and assess for headache, nausea, and vomiting.
COMPLICATIONS OF AV FISTULAE OR SYNTHETIC AV GRAFT Stenosis the most frequent cause of permanent peripheral hemodialysis access failure is vascular stenosis. Thrombosis this complication is more common in synthetic AV grafts than native AV fistulae. Failure of maturation a native AV fistula requires 1 to 4 months to mature; if blood flow is diminished by stenosis or multiple outflow veins, maturation will be impaired. Infection a leading cause of complications and death in dialysis patient. Typical S/S of an infected dialysis access include local erythema, induration, tenderness, and purulent drainage from incision sites. Ischemic steal syndrome diverting blood flow from the distal extremity through the hemodialysis access may cause pain and ischemia in some patients, esp.diabetic and elderly patient. Pseudoaneurysm also called false aneurysm or pulsating hematoma
TYPES OF VASCULAR ACCESS FOR HEMODIALYSIS
PERITONIAL DIALYSIS Peritoneal dialysis (PD) takes place within the peritoneal cavity. PD is slower than hemodialysis, However, and more time is needed for the same effect to be obtained.
PROCEDURE AND PROCESS The surgical insertion of a siliconized rubber (Sillastic) catheter into the abdominal cavity is required to allow the infusion of dialyzing fluid (dialysate) is infused according to the physician order, 1 to 2L of dialysate is infused by gravity (fill) into the peritoneal space over a 10 to 20 minutes period, according to the clients tolerance. The fluid dwells in the cavity for a specified time ordered by the physician. The fluid then flows out of the body (drain) by gravity into a drainage bag.
Cont of process and procedure the peritoneal outflow contains the dialysate in addition to to the excess water, electrolytes, and nitrogenous waste products that have accumulated in the body. The Three Phases of the process: 1.Infusion or fill. 2.Dwell 3.Outflow or drain. PD occurs through diffusion and osmosis across the Semipermeable peritoneal membrane and adjacent capillaries. The peritoneal membrane is large and porous. it allows solutes, which carry fluid with them to move by an osmotic gradient fr an area of higher concentra- tion in the body (blood) to an area of lower concentration in the dialyzing fluid.
Complications of CAPD PERITONITIS the major complication of PD. The most common cause of peritonitis is contamination of the connection site during an exchange. The infection of peritoneum is manifested by cloudy dialysate outflow (effluent), fever, rebound abdominal tenderness, abdominal pain, general malaise, nausea, and vomiting.. Cloudy or opaque effluent is the earliest sign of peritonitis. The best treatment of peritonitis is prevention.. The nurse must maintain meticulous sterile technique when caring for the PD catheter and when hooking up or clamping off dialysate bags.
Cont of Complication of CAPD Pain- pain during inflow of dialysate is common during the first few exchanges because of peritoneal irritation; however, it disappear after a week or two. Cold dialysate aggravates discomfort. Thus the dialysate bags should be warmed before instillation by use of a heating pad to wrap the bag or use of warming chamber. Microwave oven are not recommended for the warming of dialysate because of their unpredictable warming patterns and temperatures. Exit Site and Tunnel infections- the normal exit site from a PD catheter should be clean, dry, and with out pain or evidence of inflammation.
Cont of Complication of CAPD Insufficient flow of the Dialysate- Constipation is the primary cause of inflow or outflow problems. To prevent constipation, the physician orders a bowel preparation before placing the PD catheter. The nurse ensures that the drainage bag is lower than the client abdomen. The nurse inspects the connection tubing and PD system for kinking or twisting and rechecks to make sure that clamps are open. Dialysate Leakage- when dialysis is initiated, small volumes of dialysate are used. It may take clients 1 to 2 weeks to tolerate a full 2-L exchange without leakage around the catheter site. Other Complication- The nurse notes any change in the color of the outflow.
NURSING CARE DURING PERITONEAL DIALYSIS Evaluate baseline vital signs The client is weigh, always on the same scale, before the beginning of the procedure or at least every 24 hours while receiving the treatment. Baseline laboratory value determination, such as electrolyte and glucose levels, During PD, the nurse continually monitors the client. For the first exchanges, record the vs every 15 minutes. Ongoing assessment for respiratory distress, pain or discomfort. Abdominal dressing around the catheter exit site is checked frequently for wetness. Monitor for dwell time.
NURSING CARE CONT For hourly exchanges, dwell time usually ranges from 20 to 40 Minutes. Blood glucose assessment is necessary, due to Glucose absorption occur in some patient. The outflow is recorded accurately after each exchange. Visual inspection of the outflow bag and daily weights may be sufficient to note the adequacy of the return. If drainage return is brown, a bowel perforation must be suspected. If drainage return is the same color as urine and has the same glucose concentration, a possible bladder perforation should be investigated. If drainage is cloudy or opaque, an infection is suspected.