The substitution of renal function Pavel Tinka https://cdn. jenzeny.cz/data/image/title/2016/09/57fe7cba6f7b1.jpg?1496995452 Summary ► Intermitent methods: ► Longterm substitution ► Usually managed in intervals (e.g.: 3x per week for 5 hours, in case chronic renal failure) ► Continual methods: ► Only temporary substitution ► Without interuption, for patient in critical state Hemodialysis The most frequent used principe Blood is pumped from vessels to extracorporal circulating system Here is in touch with hemodialytic liquid The main principe of this technicque is diffusion Exchange of hemodialytic liquid is required It is better for reduction of low-molecular weight matters from blood čas 0 oozdéii • • t • » % krev % * # • ♦ membrána * ■ ■ ♦ 9 ■ » diaiyzační _ # ♦ ■ ♦ ■ rozlok 1 » . * https: //encrypted- tbn0.gstatic.com/images?q=tbn:ANd9GcSiFsaHn60yc kFzaGGlhinslAWarzTS43sySd4W0556zpZl2wrXgw Hemof Titration The main principe of this technicque is filtration Blood with its pressure is transported to semi-permeabile membrane We have to substituate the loss of liquid from blood during this technicque It is better to reduce high-molecular weight matters Unlike hemodialysis, it isn't connected with hypotension This method simulates glomerules das 0 krev membrána Cl .liy/.l.'ll https: //encrypted- tbn0.gstatic.com/images?q=tbn:ANd9GcT3Tlxy ESVOxivaSvFIIE- vEad_MxX_bGxrYnVLz6BGHmaLkmtuEQ Hemodiafiltration ► The combination of hemodialysis and hemofiltration ► We can reduce wide spectrum of metabolites ► Difuse part is the same as in hemodialysis ► Filtration part is reduced than in hemofiltration ► Also we have to substituate the loss of liquid during this process Vascular access ► For long-term hemodialysis we need good stable vessel access ► These requirements is covered only by chirurgical A-V shunt ► Usually radiocephalic shunt is used ► Shunt requires time to become ready for dialysis ► We shouldn't work with it when the local infection is present ► It should be palpable subcutaneously ► The alternative is arteficial material, but it has more complications A-V shunt Arteriovenous Fistula https://upload, wikimedia.org/wikipedia/com mons/thumb/f/fd/Blausen_0049_ArteriovenousFistula.png/400px-Blausen_0049_ArteriovenousFistula.png Vascular acces catheter ► Temporary acces until A-V shunt is prepared ► It is time limited for 3 weeks, after that the lumen could be trombotised, the efficiency is rapidly reduced ► // we have patient who will need hemodialysis, we should save his vessels to A-V shunt. Dialyzer a filter ► Today, we use capillary dialyzers, wchich substituate board ones ► Blood is flowinf in cappilars surrounded by dialysing liquid ► The trend is to make dialyzer with more biocompatibility ► Dialyzer in Czech republic is used only once vs USA ► The most important part is the dialysis membrane ► In past we use celulosis to create membranes, today we prefer modificated celulosis or syntetic materials Capilar dialýze r https: //vww Jreseniusmedicalcarexz/f Ueadmin/^ odialysis/Dialysers/FX_CorDiax/BAS020_FXClass-dialyzer.jpg Biocompability ► Membranes and other parts of machine aren't perfectly biocompatible ► It has many complications: ► Trombogenity:, use LMW heparines before procedure, or put citrate to the machine ► Pay attention if patient has coagulopathy ► Activation of complement due to arteficial membranes could damage patinet's blood cells ► Other complication is leucopenia, activated complement could sequestrate leukocytes in pulmonary blood vessels Dialyzer monitor ► Machine, where hemodialysis is situated ► It is equiped with hemopump ► It can measure pressure or recognize gas in vessel ► It is also equiped with blood detector, which could detect blood in the machine ► Machine keeps the blood warm ► An important part is the dialysing liquid The diagram of hemodialyzer , Odviduiriovaci vedtfii Krevni pumpa uniku krveT Kr*vod pacionta -_ .1 Venosmtlak o K—(£. I DeteMor vzduchu < Ver.osm bezp«£nostni ^^lapka^^^ Upravona t voda http: / /www. inmed.cz/obrazky/schema.jpg Hemodialyzer - monitor http://www.kzcr.eu/rop/data/gallery/8/big/DC_ROP_28. jpg Indications and contraindications Chronic renal failure All patients, where conservative treatment fails ► We don't start treatment in case that patient refuses it ► We can't chose this hemodialysis when patient is circulatory unstable and doesn't have vessel access ► If it isn't contraindicated, we should follow patient wish ► Hemodiafiltration or hemofiltration should be prefered in patients with long-term substitution of renal function ► It has lower risk of amyloidosis Indications ► Acute renal failure ► Usually potentionally reversible state ► We prefer hemofiltration to reduce high-molecular matters, which are connected to etiology of this disease ► It is used when conservative therapy fails ► Next indication is poison of dialysable matters (e.g.: Li, ethylenglycol, methanolum) Frequention of hemodialysis ► Patients with chronic renal failure attend 3 times per week ► One procedure takes around 3-5 hours ► We have also variant of continual hemodialsysis ► Every day for 2 hours ► Or 8-10 hours at night ► We have limited experiences with these methods Complications ► Divided in acute or chronic ► Acuted is attached for one procedure ► Chronic are created in longer period and persists for longer time Patients using hemodialysis are polymorbid, it is difficult to recognize complications from basal diseases Acute complications ► Bleeding Patients have problems with uremic coagulopathy or usage of heparines ► Blod clotting in hemodialyzer ► Hypotension ► Due to the liquid loss from blood in dialyzer ► It is bad perceived by patients, they have nauzeu, vommiting. ► Hypertonic reaction ► Excessive reaction of body to liquid loss, we should use vasodilatators ► Anafylactoid rection ► Due to bad compability of biomembranes in hemodialyzer ► Gas embolization Chronic complications Dialyzating amyloidosis ► Storage of 62-mikroglobulines, it causes carpal tunel syndrome, artropathy, artritis ► Malnutrition ► It could happen that nutritient move to dialyzating liquid ► Imunity decrease ► We speculate that long-term hemodialysis could inactivate monocytes ► Aterosclerosis We think that dialysis causes chronic inflamation which facilites aterosclerosis Continual substitution of renal function ► Effective in patients with acute renal failure ► Principles are similar to intermitent methods ► Advantage of this method is continuous elimination of toxic metabolites ► We also continuosly eliminate nutritions from blood, so patient is vulnerbale to malnutrition ► Longer contact with biomembranes increase problems with biocompability ► Different surveys show that there is no difference in effectivenes between intermitent and continual methods in patients with acute renal failure Peritoneal dialysis ► We aplicate hemodialytic liquid to intrabdominal space for continuos di ► We have exchange the liquid 3-5 times per day ► It is more similar to the renal function ► We have to put peritoneal cateter ► Usualy it is used as alternative for conventional hemodialysis ► In Czech republic we use this method in 10% cases, usualy patients with cronic renal failure Peritoneal dialysis- diagram O MAYO FOUNDATION FOR MEDICAL EDUCATION ANO RESEARCH. ALL RIGHTS RESERVED. https://vww.mayoclinic.Org/-/media/3df03453c80f4a81b00319df007399b1.jpg Advantages and disadvantages of peritoneal dialysis ► Advantages: ► We could do it regurarly in ambulance ► The character of body liquid isn't oscilating too much We could save blood vessel asses for future use of hemodialysis ► Disadvantages: ► Peritoneal infection ► Endogenous loss of protein to dialyzator ► Excess of glucose income from dilyzating liquid Indications a contraindications ► Indications ► Analogical as in hemodialysis ► Patient preferences ► Absolute indication is inability to make vascular acces ► Contraindications ► Adhesions in abdominal cavity ► Carcinomatosis of peritoneum ► Active intestinal infection ► Colostomy, nefrostomy ► Polycystic kidneys Complications ► Infectious ► Local infection ► Tunnel infection ► Peritonitis ► Noninfectious ► Catheter damage ► Extracorporeal leakage ► Hernia due to the higher intraabdominal pressure ► The damage of peritoneal filtration function "he end ► Resources: TESAŘ, Vladimír a Ondřej VIKLICKÝ. Klinická nefrologie I Vladimír Tesař, Ondřej Viklický editoři. 2015. ISBN 9788024743677.