Chronic Kidney Disease and Dialysis Patient Care – What the Generalist Should Know Nephrology Topic Review Clarian Arnett Hospital Lafayette Medical Education Foundation January 18, 2011 Stephen R. Ash, MD, FACP Clarian Arnett Health Director of Dialysis, Wellbound Director of R&D Ash Access Technology and HemoCleanse, Inc. Lafayette, IN Role of Primary Physicians in Treatment of CKD Patients and Preparing for Dialysis • Identify patients with CKD • Identify causes of kidney disease (diabetes, hypertension, obstruction, hyperuricemia, infections, obstruction, medications) • Treat the primary disease and prolong renal function, for example using ACE/ARB in diabetics with CKD • Refer to Nephrology at CKD Stage 3 (GFR=30-60 ml/min/1.73M2) • Observe for signs of uremia • Help to determine with patient, family and Nephrologist whether dialysis is indicated • Preserve arm veins for hemodialysis access • Expect and support access procedures at stage 4-5 (GFR<20 ml/min/1.73M2) • Avoid damage to fistula or graft in arm • Monitor graft and fistula function, report abnormalities 1. Dialysis Options and How They Work • • • • Peritoneal dialysis Hemodialysis CVVHD NxStage Home Dialysis Therapy Dialysis=Diffusion Nighttime cyclers decrease the number of daytime exchanges needed. The Hemodialysis Blood Side System Fresenius K-Machine NxStage Therapy System 2. Symptoms of Renal Failure (Uremia) • • • • • Gastritis: nausea, vomiting, gastritis, anorexia Fluid Overload, CHF: shortness of breath, orthopnea Encephalopathy: confusion, sleepiness, coma Neuropathy: itching, weakness Pericarditis: chest pain, shortness of breath 3. Physical • • • • • • • • Signs of Renal Failure Vomiting Edema CHF, Rales Confusion, Coma Bleeding Decreased urine output (sometimes) Hypertension Diminished inflammatory response and signs of infection 4. Laboratory Values in Renal Failure • Creatinine elevation (normal is 0.6-1.4) • GFR decrease by MDRD or CG (normal for 70 year old of 70 kg is 70) • BUN increase (normal up to 22) • Phos increase (normal up to 4.5) • Potassium increase (normal up to 5.5) • Hemoglobin decrease (normal lower limit 13) • Bicarbonate decrease (normal lower limit 24) • Hundreds of other chemical and hormonal changes 5. Medical Therapy of Chronic Renal Failure • • • • • • Potassium (bicarbonate, glucose & insulin, saline, β-agonists, Kayexelate, calcium, stop various meds) Phosphorus (calcium acetate, calcium carbonate, Renvela, Fosrenol) Urea (diet restriction, exclude GI bleed) Optimize GFR (fluid load, fluid decrease, improve blood pressure, stop various meds) Avoid nephrotoxic meds (nsaids, ACE, iodinated contrast agents) Avoid or adjust other toxic meds (MRA contrast, Reglan, Digoxin, Amiodarone, Lovenox, etc). 6. When do we start dialysis in CKD? Which Type? • • • • • Clearance – GFR < 15 ml/min for non-diabetics (MDRD) – GFR < 25 ml/min for diabetics – Downward trend in GFR – Upward trend in uremic toxins Symptoms Quality and length of expected life Home patient potential: good patient historically, family support and partner, mobility, interest and capability – PD, especially for heart failure, diabetes, provides several years of support – Short daily Hemo: capability and interest – Overnight Hemo 8 hours every other night also possible In-center patient potential – Must tolerate surgery or procedures for vascular access device – Must tolerate rapid fluid shifts and heart strain – Must cooperate with medical regimen – Transportation must be available for three treatments per week Stages of Chronic Kidney Disease Description eGFR (ml/min/1.73m2) I “Normal” Renal function >90 II “Mild” Renal Dysfunction 60-89 III “Moderate” Renal Dysfunction 30-59 IV “Severe” Renal Dysfunction 15-29 V “End-Stage” Renal Disease <15 Stage 7. Requirements for Hemodialysis Access • Blood flow rate of 400 ml/min for 4 hours treatment, without blockage • Blood flow rate in vicinity of access (like catheter or needle) must be at least 800 ml/min • Minimal infection risk • Low risk of bleeding • No tubes through the skin if possible • Longevity in years, not months Types of Hemodialysis Access • AV Fistula • AV Graft • Tunneled Internal Jugular dialysis Catheter Scribner Shunt-1960 Short History of Hemodialysis Access after Scribner Shunt: AV Fistula Original Cimino-Brescia Fistula; side-by-side Other types of fistulas Finding Veins-Sometimes Easy, Sometimes Hard Vein Mapping to Find Suitable Veins and Arteries Fistula Problems-Stenosis Note enlargement of radial artery-to provide a liter per minute blood flow Signs of Venous Stenosis in Vascular Access Physical Exam..Detects Inflow Problems and Outflow Problems Aneurysms are Weakened Areas, not Able to Receive More Needlesticks But, 30-50% of fistulas don’t work in the first place…. AV Grafts ArterioVenous Grafts Can Teflon be a Blood Vessel? Grafts Become Covered by Body Tissues, Sometimes Too Much Tissue And Stenosis Near the Connection of the Graft and Vein Infection is Rare, Redness is Common Pseudoaneurysms are Near Blowouts Tunneled Permanent Central Venous Catheters for Dialysis The Third Choice But as CMS Reports: We have a Continuing Dependence on CVCs… BFRs w/ Vascular Accesses Dacron Cuff is under the skin Tips are at the entry to the heart Wardrobe Requirements Natalie Cole, 2009 Did you notice this first? Exact placement is sometimes difficult… Vein entry is with Ultrasound Problems Include Clotting And Fibrous Sheathing Catheter Sheaths develop at point of contact to vein or atrial wall… Fibro-Epithelial (Fibrin) Sheath L IJ CVC FibroEpithelial Sheath SVC RA Courtesy, Arif Asif KDOQI 2007 Risky! Exchange? Balloon sheath? Brush? 30 minutes? Overnight? Can catheter outcomes be improved? For sheathing, new catheter designs might help… Centros Tips form a flat plane; ports are held in middle of vein CentrosTM: Preferred Placement in SVC art ven art ven The catheter tips are positioned in the lower third of the SVC rather than in the atrium… Centros™: A Self Centering Catheter tip tip Pacemaker leads The ports are held in the middle of the SVC and away from the vein wall. These CT’s were performed after 4 months of catheter use. CentrosTM: Preliminary Study Results Average Flow at -200 Arterial Pressure, Centros(TM) Catheters (+/- Standard Deviation) 500 ml/min 400 300 200 100 0 0 1 2 3 4 w eeks 5 6 7 Standard Catheters P < 0.05 (n=120) Flow rate of the CentrosTM Catheters was 400 ml/min, constant over time (7 weeks) and higher than with current Dual Lumen tunneled dialysis catheters. Infection in Tunneled CVC for Dialysis • • • • • • Incidence of 1-5/1000 patient days, or 3-15% of patients per month (higher in non-tunneled catheters) Serious consequences, systemic and metastatic infections Highly costly Requires long-term systemic antibiotics and usually antibacterial catheter lock to resolve For Staph Aureus or Pseudomonas organisms catheter must be removed/replaced Prophylactic antibiotic or antiseptic locks can diminish incidence but have their own problems