6b RENAL REPLACEMNT THERAPY Year 4 Internal Medicine Notes

6b RENAL REPLACEMNT THERAPY Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / IMED 4.2 / Mogere -- Slide 1 RENAL REPLACEMNT THERAPY Dr. Alex Mogere Consultant physician Slide 2 Introduction The aim of RRT is to replace the excretory functions of the kidney, and to maintain normal electrolyte concentrations and fluid balance Slide 3 defn It’s a therapy that replaces the normal blood filtering role of the kidney Used in AKI or CKI Slide 4 Epidemiology The median age of patients starting RRT in the UK is 65 years and 24% have a primary renal diagnosis of diabetic nephropathy. in the USA, incidence rates for RRT in 2010 were about three times higher than in the UK at 348 per million population Following initiation of dialysis in the UK, the survival is 84% at 1 year and 50% after 5 years IN Kenya 2016 study-62.8% of HD pts were male, mean age 63 yrs, 60.5 % had both htn and dm 51 dialysis centres across Kenya- 2019 Dialysis units 2022-public 214, private 143, Faith based-17 5670 pts on HD in 2021- KRA Prevalence of CKD in sub Saharan Africa- 14%, 4% in Kenya HD first introduced in Kenya in 1972 Chronic HD- introduced in KNH in 1984,in private hospitals- 1982 Slide 5 Dialysis All dialyses modalities can be used to ensure equivalent solute clearance and ultrafiltration Choice of procedure dependent on: CVS status Age Available expertise Availabilty of vascular status Integrity of peritoneal membrane and abdominal cavity Slide 6 Cost of dialysis in kenya KNH- 5k/session Private 7.5K-9k/session Slide 7 Indications of Dialysis in AKI Uremia Metabolic acidosis Hyponatremia Hyperkalemia Fluid overload Hypercatabolic state Slide 8 Indications of Dialysis in CKD Intractactable intravascular vol overload GFR <15ml/min/1.73/m2 BSA Growth failure Severe electrolyte disturbances Slide 9 Preparation for RRT Nephrologist review early At the present time, the average eGFR at the time of initiating RRT in the UK is about 8 mL/min/1.73 m2 but there is wide variation overall aim is to commence RRT by the time symptoms of CKD have started to appear but before serious complications have occurred.\nPsychological/social support Discuss various options of tx Slide 10 Modalities of RRT Haemodialysis Haemofiltration Peritoneal dialysis Renal transplantation Slide 12 Differences between hemodialysis and peritoneal dialysis Slide 13 Acute peritoneal dialysis Ultrafiltration and diffusive transport Ultrafiltration involves exchange of solutes and movement of fluid across the semipermeable peritoneal membrane Diffusive transport: solutes are exchanged across their conc gradient btwn the peritoneal capillaries and the dialysis soln. The most widely used catheter is the polyurethane trocar catheter Slide 14 Peritoneal dialysis solution Dextrose as the osmotic agent: conventional Non dextrose cont solns: reduce risk of hyperglycemia Other solutes available: lactate, sodium, calcium Slide 15 Complications Gut perforation Post catheter insertion bleeding Abdominal pain Exit site infections Difficult drainage Leakage around catheter Metabolic disturbances Slide 16 Chronic peritoneal dialysis(CPD) Two types: CAPD(cont. ambulatory PD) and CCPD(cont. cycling PD) In CAPD, about 2 ltrs of sterile, isotonic dialysis fluid are introduced and left in place for approximately 4–6 hours. The fluid is then drained and fresh dialysis fluid introduced, in a continuous four-times-daily cycle The inflow fluid is rendered hyperosmolar by the addition of glucose or glucose polymer;\nAutomated peritoneal dialysis (APD) is similar to CAPD but uses a mechanical device to perform the fluid exchanges during the night, leaving the pt free, or with only a single exchange to perform, during the day Slide 17 CCPD(APD) Involves frequent continous cycling of dialysate at night while the child is asleep, then leave a small amt of dialysate during daytime Slide 18 CPD utility useful in children first Tx in adults with residual renal function Tx for elderly pts with cvs instability Slide 19 Haemodialysis Is the most common form of RRT in ESRD\ninvolves gaining access to the circulation, either through: an arteriovenous fistula(AV fistula) –radial artery to cephalic vein, brachial artery to cephalic vein,or brachial artery to a basilica vein a central venous catheter or an\narteriovenous shunt, such as a Scribner shunt The composition of the dialysate can be varied to achieve the desired gradient and fluid can be removed by applying negative pressure to the dialysate side Slide 20 Hemodialysis circuit Slide 21 Haemo Dialysis machine Slide 22 HD in progress Slide 23 Ct. Hemodialysis vascular access Tunnelled cuffed catheter Slide 24 Ct. Hemodialysis vascular access AV fistula Slide 25 AV Fistula Slide 26 Ct. Hemodialysis vascular access AV Graft Slide 28 Dialyzers and blood tubing Most dialyzers are hollow fiber Most made of modified cellulose or entirely of synthetic mtrl Slide 29 Length and frequency of dialysis Aim is for 30% reduction in BUN during the 1st di