ESRD causes: DM, HTN, others include GN, PKD, obstructive uropathy
Mortality from HD due to: cardiovascular dz (50%), and infections
Hemodialysis Indications:
Hyperkalemia (refractory)
Volume overload - CHF
pH <7.2 (metabolic acidemia)
Uremic encephalopathy
Uremic pericarditis with or without cardiac tamponade
GFR is <10 ml/min in non diabetics or <15 ml/min in diabetics
Progressive motor neuropathy
KT/V = 1.2 per HD Tx is the minimum standard
URR (urea reduction ratio) of 65%
URR = pre-HD BUN x post-HD BUN divided by pre-HD BUN. Multiply by 100.
Complications during HD and Mgmt
Hypotension - most common cause. 2° excessive fluid removal, impaired vasoactive and autonomic responses, osmolar shifts, food ingestion, impaired cardiac reserve, use of anti-HTN meds, vasodilation due to warm dialysate, nitrates, allergic reaction to dialyzer.
R/o other causes: MI, cardiac tamponade, PE.
Active bleeding & coagulopathies: reduce heparin during HD. DC heparin in uremic pericarditis, platelet dysfunction
Dialysis dysequilibrium syndrome: occurs during first few HD Tx in uremic Pts 2° CNS edema from rapid osmolar shift: N/V/HA, confusion/Sz
Muscle cramps
Pt. on chronic medications: cardiac, warfarin, chemotherapy, etc. dramatically drop their serum drug levels during dialysis.
Dialysis Pts are frequently instrumented and combined with their impaired immunity, infection is common. Subacute bacterial endocarditis may occur if the infections are not recognized early and treated correctly.
Viral hepatitis: frequent blood transfusions
Psychologically, dialysis can be extremely burdensome.
Management:
D/C ultrafiltration, 0.9% NS bolus IV, give salt poor albumin to pts with hypoalbuminemia, check daily dry weight, hold anti-HTN 1 day prior and day of HD, avoid heavy meals during HD.
For muscle cramps: reduce volume of fluid removal during HD, use higher conc. of Na+ in dialysate, Quinine sulfate, 260 mg PO x 1, 2-h before HD.
Increase protein intake 1 - 2 g/kg/day
Adjust fluid intake to permit wt. gain ~2 kg between HD sessions.
AVF optimal form of HD access: reduced risk of inf. and thrombosis, should be placed 3 - 6 mo prior to anticipated HD because it takes time to mature.
AVG/shunt placed 1 - 3 mo ahead of anticipated HD.
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Urea Reduction Ratio: ~65%
URR = (pre-HD BUN - post-HD BUN)/pre-HD BUN) x 100
Drugs in Renal disease:
Meperidine is a narcotic analgesic. Meperidine (Demerol), 50 - 150 mg PO, SC, or IM q2 - 3h causes less biliary spasm, urinary retention, and constipation than morphine but results in more respiratory depression and is a myocardial depressant. It is C/I in Pts who are taking MAO-I and is cautioned in individuals with renal failure (accumulation of metabolite, normeperidine, causes CNS excitement and seizures). Repetitive dosing is more likely to cause seizures; therefore, chronic administration is not recommended.
Meperidine undergoes extensive hepatic metabolism, but its metabolite normeperidine undergoes renal metabolism.
Reglan: 1/2 dose for non-renal Pts.
Dofetilide and sotalol undergo predominantly renal excretion and carry a risk of QT prolongation and arrhythmias if doses are not reduced in renal disease.
Sotalol can be given 40 mg after dialysis (every second day)