Kidney replacement therapy takes over the kidneys' job of removing wastes, excess fluid, potassium, and acid. Options are hemodialysis (HD), peritoneal dialysis (PD), continuous kidney replacement therapy (CRRT) in intensive care, and kidney transplantation. The older term "renal replacement therapy" is still common.

Principles

• Diffusion — solutes move from higher to lower concentration across a semipermeable membrane (removes urea, creatinine, potassium)
• Osmosis / ultrafiltration — water is removed by pressure (HD) or by an osmotic agent such as dextrose (PD)

When to start — the decision is based on the overall clinical picture, not a single creatinine value:

• Refractory hyperkalemia, severe metabolic acidosis, or fluid overload (pulmonary edema) not controlled by medication
• Uremic complications: pericarditis, encephalopathy, bleeding
• Uremic symptoms despite conservative care: persistent nausea, vomiting, anorexia, malnutrition, pruritus, fatigue
• Certain poisonings (e.g., lithium, methanol, salicylates) in acute settings

Before and after each hemodialysis session

• Weight (compare with target "dry" weight), BP (lying and standing), pulse, temperature, lung sounds, edema
• Vascular access: palpable thrill and audible bruit mean the fistula or graft is patent; check for redness, warmth, drainage (infection), and hand coldness, pallor, pain, or numbness (steal syndrome)
• Labs: potassium, BUN, creatinine, hemoglobin

Signs of inadequate dialysis — persistent fatigue, anorexia, nausea, pruritus, poor concentration, rising potassium; adequacy is measured by urea clearance (Kt/V; minimum about 1.2 per session for thrice-weekly HD)

Peritoneal dialysis

• Effluent: normally clear, pale yellow; cloudy effluent = peritonitis until proven otherwise; bloody (except with menstruation or after catheter placement) or fecal effluent is abnormal
• Exit site: redness, crusting, drainage, tenderness
• Balance of fluid in versus out; weight; abdominal distension; respiratory effort during dwell

• Serum K⁺, BUN, creatinine, bicarbonate — before and after dialysis
• Kt/V or urea reduction ratio — dialysis adequacy
• Hemoglobin, iron studies — anemia management
• Calcium, phosphorus, PTH — mineral-bone disorder (renal osteodystrophy)
• Albumin — nutrition; low albumin predicts higher mortality
• PD effluent cell count, Gram stain, and culture when peritonitis is suspected — peritonitis is likely when effluent WBC > 100/µL with > 50% neutrophils (after a dwell of at least 2 hours)
• Access imaging (ultrasound, fistulogram) if flow is poor
• Transplant: drug trough levels (tacrolimus, cyclosporine), creatinine, biopsy for suspected rejection

Hemodialysis vascular access

• Arteriovenous fistula (AVF) — the client's own artery and vein joined, usually in the nondominant forearm or upper arm; lowest infection and clotting rate; needs about 6–12 weeks or longer to mature
• Arteriovenous graft (AVG) — synthetic tube; usable in about 2–3 weeks; higher clotting and infection risk
• Central venous catheter — immediate use but highest infection risk; only nurses trained in dialysis catheter care should access it
• Current US guidance (KDOQI 2019) recommends choosing access through an individualized "ESKD Life-Plan" rather than "fistula first" for everyone

Peritoneal dialysis

• Dialysate contains dextrose (or icodextrin); higher dextrose removes more fluid but adds glucose load
• Icodextrin can falsely raise glucose readings on some meters (GDH-PQQ strips) — use a glucose-specific method; missed hypoglycemia or insulin given in error can be fatal
• Peritonitis: intraperitoneal antibiotics are preferred, started promptly after effluent samples are sent

CRRT — for hemodynamically unstable ICU clients who cannot tolerate HD

• Citrate anticoagulation can cause hypocalcemia (check ionized calcium) and metabolic alkalosis; heparin raises bleeding risk and HIT risk
• Monitor for hypothermia, hypophosphatemia, hypokalemia, and filter clotting

Kidney transplant

• Living or deceased donor; the new kidney is placed in the iliac fossa, and the client's own kidneys usually stay
• Lifelong immunosuppression — usually a combination:

• Prophylaxis against Pneumocystis (e.g., TMP-SMX) and cytomegalovirus per protocol; no live vaccines after transplant

Listed in priority order.

1. Respond to emergencies during hemodialysis
   • Air embolism — sudden dyspnea, chest pain, cyanosis, hypotension: clamp the blood lines, stop the pump, place client on the left side with head down, give oxygen, call for help
   • Hypotension (the most common complication) — stop or reduce ultrafiltration, lower the head of bed (Trendelenburg as tolerated), give prescribed saline bolus
   • Dialysis disequilibrium syndrome — during or soon after the first sessions, rapid urea removal makes plasma less concentrated than brain tissue → cerebral edema: headache, nausea, restlessness, confusion, seizures. Prevent with shorter, slower initial sessions; slow or stop the treatment and notify the provider
   • Chest pain with hypotension, muffled heart sounds, and JVD in a uremic client suggests pericardial effusion/tamponade — report immediately
   • Bleeding (heparin) and muscle cramps (rapid fluid removal)
   • Access hemorrhage (e.g., needle dislodgement or ruptured access) — apply firm direct pressure and call for help
2. Protect the vascular access
   • No BP measurement, venipuncture, or IV in the access arm; post a sign
   • Check thrill and bruit each shift; report absence (thrombosis)
   • No tight clothing, jewelry, or sleeping on the arm; no heavy lifting with that arm
3. Peritoneal dialysis safety
   • Hand hygiene and aseptic technique for every exchange (many programs also require a mask)
   • Warm dialysate to body temperature using dry heat (a manufacturer warmer or heating pad) — never a microwave (uneven heating) and never immersion in water (contamination); cold fluid causes abdominal pain
   • Suspected peritonitis (cloudy effluent, abdominal pain, fever): obtain effluent sample for cell count, Gram stain, and culture first, then start prescribed antibiotics without delay
   • Slow drainage: check for kinks and closed clamps, turn the client side to side, raise head of bed, prevent constipation (full bowel blocks outflow)
   • Dyspnea during dwell: raise head of bed; drain if severe and report
4. Fluid and medication management
   • Weigh before and after dialysis; strict intake and output
   • Hold antihypertensives and dialyzable drugs before HD if prescribed (hypotension, drug removal); give after treatment
5. Transplant care
   • Hourly urine output early after surgery (large diuresis is common, or delayed function may require dialysis)
   • Watch for rejection: decreased urine output, rising creatinine, weight gain, fever, graft tenderness, hypertension
   • Strict infection prevention; give immunosuppressants on time

Hemodialysis

• Check the fistula daily by feeling for the thrill (a buzzing vibration); report if it is absent
• Protect the access arm: no BP cuffs, blood draws, tight sleeves, watches, or heavy bags on that arm; do not sleep on it
• Hand exercises (e.g., squeezing a soft ball) during fistula maturation if prescribed
• Keep the access clean; report redness, drainage, fever, or cold, painful fingers
• Limit fluid, sodium, potassium, and phosphorus; aim for weight gain between sessions of no more than about 1–1.5 kg (2.2–3.3 lb) per day, or as the unit specifies; protein intake increases once on dialysis (about 1.0–1.2 g/kg/day) because dialysis removes protein
• Take phosphate binders with meals, not after
• Thirst control: ice chips (count them as fluid), sugar-free gum or hard candy, cold fruit slices within the potassium limit, oral care

Peritoneal dialysis

• Wash hands thoroughly before every exchange; use strict technique
• Exit site: clean daily with soap and water or prescribed cleanser, dry, apply prescribed antibiotic cream daily; do not pull off crusts; keep catheter secured to prevent pulling
• Showers are allowed with the site protected per program; avoid tub baths, hot tubs, and swimming in lakes or rivers
• Cloudy fluid, abdominal pain, or fever: call the PD unit immediately and bring the bag
• Weigh daily; record effluent volume and appearance; high-protein diet; watch glucose (dextrose absorption)

Transplant

• Never miss or stop immunosuppressants; keep drug levels on schedule; avoid grapefruit and check all new drugs and supplements
• Report signs of rejection or infection promptly; sun protection (skin cancer risk); no live vaccines

• Hemodialysis: hypotension, air embolism, disequilibrium syndrome, access thrombosis or infection, steal syndrome, catheter bloodstream infection, hemorrhage
• Long-term HD: dialysis-related amyloidosis (beta-2 microglobulin deposits — carpal tunnel syndrome, assessed with Tinel and Phalen signs), renal osteodystrophy, cardiovascular disease, malnutrition
• Peritoneal dialysis: peritonitis (most serious), exit-site and tunnel infection, hernias, hyperglycemia, weight gain, protein loss, pleural leak
• CRRT: hypothermia, hypocalcemia (citrate), bleeding, electrolyte depletion
• Transplant: rejection (hyperacute — minutes; acute — most within the first months; chronic — gradual), infection (CMV, BK virus), calcineurin inhibitor nephrotoxicity, post-transplant diabetes, cancer

• KRT start is based on symptoms and complications (hyperkalemia, acidosis, fluid overload, pericarditis, encephalopathy, uremic symptoms) — not a creatinine number alone
• Thrill (felt) and bruit (heard) = patent fistula; no BP, blood draws, or IVs in the access arm
• HD complications: hypotension (most common), cramps, disequilibrium syndrome (first sessions, cerebral edema), air embolism (left side, head down)
• Inadequate dialysis → fatigue, anorexia, nausea (persistent uremia); monitor Kt/V
• PD: hand hygiene is the key to preventing peritonitis; cloudy effluent → send effluent for culture and cell count, then antibiotics
• Warm dialysate with dry heat; never microwave
• Slow PD outflow: check kinks and clamps, reposition, treat constipation
• Do not remove exit-site crusts; secure catheter
• Protein increases on dialysis; phosphate binders with meals; ice chips for thirst
• Cyclosporine/tacrolimus: nephrotoxicity and hypertension; monitor trough levels; avoid grapefruit
• CRRT for unstable clients; citrate → hypocalcemia