Hemodialysis Flashcards
most appropriate referral to nephrology
stage 3b or 4
rule of 6 in AVF
at least 6 mm in diameter
at least 6 cm of overall needle accessible length
no more than 6 cm below the surface
Rule of 6’s 6 weeks after the AV fistula has been placed, the fistula should: • Be able to support a blood flow of 600 ml/min • Be at a maximum of 6mm from the surface • Have a diameter greater than 6 mm
advantage of end ro side appeoach
avoidance of venous htn
ideal hd access
high prrimary patency rate
instant usability
long survival
low thrombosis rate
low infection rate
high blood flow rate
patient comfort
bathing/hygiene
minimize needles
minimal cosmetic effect
duration of lack of change on physical examination prognostic of nonmaturation
4 to 6 weeks
most impt monitoring technique
good pe of av shunt
acess placement
gfr < 20
factors influencing effective clearance: small molecules
Small FATmembrane
flow (blood/dialysate)
area (membrane surface)
Time (treatment time)
membrane permeability
most impt intrinsic physical feature governing removal
size of molecule
guards against excessive suction on the vascular access
arterial pressure
normal: -20 to 80
gauges resistance to blood return
venous pressure
+ 50 to + 200
affect solute clearance of a hemodialyzer
Increase clearance
- porosity, surface area, hydrophilicity, blood/dialysate flow
decrease clearance
- thickness, molecular weight/size, lipid solubility, protein binding, unstirred layer
varies
-membrane charge
degree to which membrane activates blood components
biocompatibility
min accetable internal fiber diameter
180 mcm
target aluminum level in water
< 10 mg/L
osteomalaciac microcytic anemia, encephalopatjy
direct exposure to this causes hemolysis and methemoglobinemua
chloramine
cardiac arrhythmia and acute death
Fluoride
Hard water syndrome - nausea vomiting weakness flushing labile bp
Excess ca and Mg
target temp of water
77F-100F
quality of dialysis water
lower maximal level of 100 cfu/ml bacteria and a max concn of less than 0.25 eu/ml for endotoxin
action levels
25 cfu
0.125 eu/ml
ultra pure dialysate
bacterial count of less than 0.1 cfu/ml
endotoxin less than 0.03 eu/ml
monitoring of water quality
monthly
post bun sampling
slowing the blood pump to 100 ml/min for 15s, stopping the dialysate flow for 3 mins, drawing sample from dialysate inflow port
clinical conditions with no anticoagulation or reginal anticoagulation
actively bleeding
significant risk for bleeding
major thrombi static defect
major sx within 7 fays
intracranial sx 14 days
biopsy of visceral organs with 72h
pericarditis
Low dose heparin clinical conditions
Major sx beyond 7 days
biopsy if visceral organs beyond 72h
minor sx 8h prior
minor sx within 72h
either low dose or no anticoagulation
major sx 8h prior
to prevent clotting
rinse circuit with heparinized saline
less thrombogenic dialyzer
flush the circuit with 100 to 200 ml 0.9% Nacl every 30 mins
avoid blood or platelet transfusion through circuit
high blood flow rate
limit uf
Mg for persistent intradialytic hypotension
Higher dialysate Mg
Adynamic bone disease
lower dialysate Mg
major complication of bicarbonate dialysate
bacterial contamination and precipitation of Ca and Mg salts
surrogate marker for cardiovascular disease in hd
carotid intimal thickness
reduce plasma isoprostanes and isofurans, markers of oxidative stress and endothelia function
coenzyme q10
surrogates of overall bp status
prehd and post hd bp
htn meds removed poorly with hd
losartan, fosinopril, ramipril, carvedilol, bisoprolol, propranolol
when can false positive hbsag occur
3 weeks
decrease in sbp 20 mmhg or more or a decrease in map of 10 mmhg with clinical events
pas <90
hypotension arterial interdialitica
maior mortalidade, maior atordoamento cardiaco,
aumento do risco de trombose da fav
causas de hid:
peso seco baixo, uf muito alta, tempo muito curto com uf alta
vasocontriccao insatisfatoria= temp elevada, sodio baixo , neuropatia autonomica, alimentacao na dialise, anemia, uso de anti hipertensivos
fat cardiacos= disfuncao diastolica
outras=tamponamento, iam, hemorrgia, sepse, reacao ao dialisador, hemolise, embolia gasosa
usar midodrina, sertralina, fludrocortisona
interventions to consider in recurrent intradialytic hypotension
reassess dry wt
reduce id Na gain
assess id hypoca, hypoK, hypoNg
avoid food intake during hd
adjust antihtn
assess cardiac function
cool dialysate
extend dialysis time or add sessions
sequential Uf or uf remodeling
midodrine
manitol
hemodiafiltracao
uso de diureticos, baixar a ingesta de sodio
measures in sindrome do desquilibrio
sindrome do desequilibrio= ocorre pq na uremia tem um aumento da osmolaridade e a queda rapida pode ocorrer a sindrome do desequilibrio
- shorter tx times of 1-2h- limitar a sessao a 2-2,5h
- lowering blood flow rates to 200-250 ml/min
- Reducing dialysate flow rate, concurrent flow
- dialyzer with small surface area
- Mannitol 1g/kg
6-perfil de sodio ou sodio mais alto
7 considerar crrt = hemorragia intracerebral, massa crebral, trauma cerebral
pericaridits that occurs within 8 weeks of initiation of hd
uremic pericarditis
complicacoes da HD
sindrome do desequilibrio
embolia gasosa
hemolise
hemorragia do acesso
saida da agulha de puncao
reacao alergica
parada cardiaca
erros na prescricao
reacoes anafilaticas
type A reactions -raro- ANAFILATICA => dialyzer reaction that occur within 5 to 20 mins and present with pruritus, urticaria, bronchospasm or anaphylactic shock,tosse , dispneia, dor abdominal
causas =oxido etileno, ieca, bacterias,reutilizacao de dialisador
cause of first use syndrome =IgE antibodies to membrane material or ethylene oxide
parara a dialise, nao devolver, pincar as linhas.
antialergico, corticoide, adrenalina- mudar a membrana,tentar hd sem heparina
-Type B=Complement mediated, occur later, chest and back discomfort =30-60minutos, causa desconhecida
continuar a dialise, tentar oxigenio, tentar mudar a membrana
complicacoes reacoes anafilaticas
tipo A- anafilatica, mais grave, nos primeiro minutos
mediada por igE= calafrios, urticaria, tosse prurido hipotensao estridor PCR
ou altos niveis de bradicinina uso de ieca
reacao com a membrana ou oxido de etileno
procurar a causa, tentar dialisar sem heparina, nao devolver, pincar as linhas
corticoide, adrenalina , antialergicos
tipo B -mediada por complemento apos 15-30minutos
dor nas costas ,nauseas vomitos, dor no peito.
trocar o dialisador
capilar de polisulfona
hemolise
chest tightness, back pain, shortness of breath with acute pigmentation of the skin and port wine appearance of the blood in venous line
acute hemolysis
discontinue without blood return
check K, peripheral smear, hgb
screen dialysate and blood tubing for contaminants
causas de hemolise= contaminacao por cobre, zinco, nitrato, nitrito e cloramine
dialisato hipoosmolar, hipertermia
ma oclusao da bomba de sangue, dialise de alto fluxo c agulha unica, oclusao parcial do cateter, kink , defeitos na linha
paciente relacionado=esferocitose hereditaria, anemia falciforme, hemolise autoimune
embolia gasosa
Stop blood pump,clamp venous dialysis line to prevent further air entry
administer O2
volume resuscitation
keep patient supine
air entra no circuito pelo acesso ou pelo circuito do dialisador
defeitos nas conexoes
priming inadequado
medicacao administrada inadequadamente
implante ou retirada de cateter
foam in venous line
pessoal treinado, evitar fluxos muito altos manter nivel de sangue alto no catabolhas
ALTERAÇOES HEMODINAMICAS RELACIONADAS A FAV E PTFE
imediatas: aumento do debito cardiaco 10-20%
aumento ativ simpatica
diminuicao da resist periferica
aumento da fc
efeitos em 1 semana= aumento do volume sanguineo causando aumento do ve aumento anp e bnp
diminuicao da resistencia vascular
diminuicao da renina e aldosterona
long terms- hipertrofia de ve
aumento debito cardiaco
isquemia coronaria
estenose venosa
avf has bounding pupsation, inc aneurysm size, does not flatten when arm raised above the head
venous outflow or central venous stenosis
estenose venosa= veias nao colapsam quando eleva o braco , tempo de sangramento prolongado, pressao venosa alta, baixo fluxo,
aneurisma distendido, hiperpulsatil, sopro e fremito param no local da estenose
estenose central= dificuldade de canular, baixo fluxo, aumento pressao venosa, braço edemaciado, veias nao colapsam
pulso e fremito variaveis
estenose arterial= dificuldade de canulacao, pressao arterial negativa , baixo fluxo, hipopulsatil,
fremito e sopro, descontinuo ou diminuido
sindrome de roubo de fluxo
sindrome de roubo de fluxo da coronaria
IC DE ALTO DEBITO
complicacoes da fav
trombose= dor, palpacao do trombo, ausencia de fremito
estenose= dificuldade de canular, edema doloroso, sangramento prolongado,
icc=dispneia, ortopneia, dispneia paroxistica noturna, edema
neuropatia isquemic= dor distal a anastomose, perda da sensibilidade, fraqueza nas maos e dedos, paralisia
sindrome do roubo=cianose de extremidade, diferenca de temperatura, dor, ulceracao, necrose , gangrena. side to side anastomososis
aneurisma= sinais de sangramento, infeccao, ulcera
infeccao=dor, calor, rubor, edema
fav
Finding what It Suggests
Head: Facial edema Superior vena cava stenosis
Neck: Scars (prior central venous catheters)/Increased risk of central venous stenosis
Chest: Edema Breast swelling Collateral veins Implantable devices
Central vein stenosis
Increased risk of central vein stenosis
Arm:
Edema Central vein stenosis
Collateral vein(s) Stenosis near the vein(s) Aneurysms and pseudoaneurysms Outflow stenosis Visible pulsation Outflow stenosis
Hand:
Cyanosis,pallor, skin necrosis, or dystrophic nails =
Vascular steal syndrome
fav
Clinical Pearl: True aneurysms are dilations involving the entire vessel wall, whereas pseudoaneurysms are dilations secondary to hematomas that occur at sites of repetitive cannulation. Unlike true aneurysms, pseudoaneurysms are not covered by the vessel wall. Glassy, thin skin or presence of ulceration over an aneurysm or pseudoaneurysm requires urgent surgical evaluation, due to high risk of AV access rupture .
arm elevation test
s a simple method to diagnose outflow vein stenosis. Under normal circumstances, when the fistula arm is raised above the level of the heart, the fistula will collapse. If an outflow stenosis is present, the area of the fistula distal to the stenosis will remain distended. Note: this test works best with forearm AVFs and is not valid for AVGs. Patients can be taught to perform the arm elevation test as a way to self-monitor their AV accesses
Stenotic lesions
intensify the thrill over the area of stenosis and lead to loss of the diastolic component.
An extremely strong (“water-hammer”) pulse over an AV access is concerning for venous outflow stenosis.
Weak pulsation suggests a problem with the inflow. In an AV graft, it is normal to feel a strong thrill at the arterial anastomosis that diminishes slightly as you move closer to the venous outflow
The pulse augmentation test is used to evaluate the inflow.
The AV access is completely occluded several centimeters above the arterial anastomosis with one hand, while the other hand is used to assess the quality of the pulse. Increased pulse intensity (augmentation) with occlusion of the outflow vein is a normal finding. Failure of the pulse to augment when the outflow vein is occluded suggests the presence of inflow stenosis.
The pulse augmentation test may also be used to assess the direction of blood flow in an AVG. When the center of the AVG is occluded, the side with an intensified pulse is the portion of the AVG that is connected to the artery, while the side without pulsation is the portion of the AVG connected to the vein.
The augmentation test. The left hand (A) is used to occlude access outflow while the right (B) is used to assess the intensity of the pulse. From Salman and Beathard, CJASN, 2013.
he sequential occlusion test is used to determine the presence of collateral veins.
Similar to the pulse augmentation test, one hand is used to occlude the AV access outflow while the other hand is used to palpate the thrill. The AV access is occluded progressively further down the venous outflow tract. If no collateral vein is present, no thrill will be felt. However, if a thrill is palpable despite occlusion of the AV, that indicates the presence of a collateral vein below the point of occlusion.
trombose da fav
dor, ausencia de pulso
estenose
sangramento prolingado, edema, dificuldade de canulacao
anti has e dialise
nao removiveis na dialise= bras,anlodipina, nifedipina (pouco), verapamil pouco, carvedilol zero, labetalol <1%,hidralazina
clonidina 5%
removiveis
minoxidil
<30% diltiazen, benzapril, ramipril, enalapril
atenolol = 75%
lisinopril 50%
metildopa 60%
Central vein stenosis
Patient has central venous stenosis and has symptoms of venous hypertension (swelling hand, dilated veins).Next step is to do Fistulogram and central venogram.The treatment is angioplasty of central stenosis with or without stentingbut if it become a recurrent event then needs ligation of AVF and creation ofnew access.
K/DOQI Guideline- Indications for Fistulogram
•Swelling of whole fistula arm
Prolonged bleeding >10 mins post dialysis on more than one occasion despite optimisation of anticoagulation regime•
Increase in size of aneurysms•
Persistent problems with scabs >3mm diameter
Unable to achieve dialysis blood flow of at least 300 ml/min•
25% fall from baseline in either achieved blood ow on dialysis or stulaow (transonic measurement within rst 1.5 hrs of HD)•
Recirculation >5% on 2 consecutive dialysis sessions•
Dynamic venous pressure >150 mmHg when measured using 15Gneedles and blood ow 200 ml/min in the rst 2 - 5 mins of dialysis (risingtrend over time is more useful than a single measurement so comparewith baseline).•
Unexplained fall in 2 consecutive URR measured on a 4 hour dialysis Session
KTV STANDART DE 2,0
KTV 1,2 3X SEM
PAC BEM DIALISADO
paciente estavel, que “funciona” bem
funcao renal residual
peso seco atingido
sem anemia
sem dmo, doenca ossea
bem nutrido
acompanhamento psicossocial e educacional
encaminhado ao tx
albumina boa
controle da pa , sem hve
que nao tem desconforto
anemia, acidose ou k corrigido
como conseguir isso? fistula first , tratar cuidar do acesso, medir a diurese residual, uso de diuretico, bioimpedancia
dosar albumina,nutricionista, programa educacional
adequacao em dialise
We recommend a target single pool Kt/V (spKt/V) of 1.4 per hemodialysis session for patients treated thrice weekly, with a minimum delivered spKt/V of 1.2.
(1B) 3.2 In patients with significant residual native kidney function (Kru), the dose of hemodialysis may be reduced provided Kru is measured periodically to avoid inadequate dialysis.
) 3.3 For hemodialysis schedules other than thrice weekly, we suggest a target standard Kt/V of 2.3 volumes per week with a minimum delivered dose of 2.1 using a method of calculation that includes the contributions of ultrafiltration and residual kidney function. (Not Graded )
cateter dialise
- Identify type of catheter, tunneled or non-tunneled, trialysis or not, date of placement and location in note
- Catheter length by side: • Right Internal Jugular 15 cm • Left Internal Jugular 20 cm • Femoral 24 cm
- No clear maximum recommended duration of non-tunnelled femoral catheter and internal jugular cathete
r • 5 days for femoral (2006 KDOQI vascular access guidelines) • 7 days for the IJ catheter (2006 KDOQI vascular access guidelines)
• No patient should go home with temporary (non-tunneled) catheters. • Most tunneled catheters are not meant to be permanent so need to have plan for fistula/graft or PD catheter placement prior to discharge
infeccao de cateter
Access-related Infection Catheter-related infection • Give vancomycin 15-20 mg/kg load AND gentamicin or tobramycin 2 mg/kg load (up to max 100 mg gentamicin) (or another antibiotic for gram neg).
Antibiotics given in the last hour of HD.
• Maintenance: 10 mg/kg vanc; gent 1 mg/kg. Monitor levels (vanc trough 15-20, gent trough < 2.0). Levels measured before HD. • Remove line ASAP with s/s of sepsis, persistent fever and bacteremia after 48 hrs, evidence of metastatic infectious, exit-site or tunnel infection, or difficult-to-cure pathogens, e.g. staph aureus, Pseudomonas, Candida/fungi, VRE, multiple-resistant pathogens. ▪ Otherwise, need at least guidewire exchange 2-3 days after starting antibiotic AND resolution of fever.
prescricao
For initial/acute HD prescriptions: Initiation of treatment to avoid dialysis disequilibrium syndrome (attending dependent) –
• 1st treatment: 90 min, Qb (blood flow rate) 150-200 ml/min, Qd (dialysate flow rate) 400 ml/min • 2nd treatment: 3 hrs, Qb 300, Qd 600 • 3rd treatment: 3.5 to 4 hrs, Qb 350 to 400, Qd 800 • Consider mannitol in extreme cases (e.g. BUN > 150 to 200 or with altered mental status). • Mannitol dose 12.5 g IV q1 hour X 2 doses (be careful if hyperkalemia because can get solvent drag that can potentially worsen serum potassium) • Alternatively consider using higher sodium bath (e.g. 145-150 meq/L). • Also no heparin if concern for pericarditis • Most units have specific dialyzer (generally smaller sized dialyzer) for first start dialysis so ask your dialysis unit charge nurse.
For chronic HD prescriptions • Qb: 400-450 ml/min (if fistula/graft), if catheter 350 (sometimes to 400). Bare minimum Qb is 150 ml/min • Qd: 600-800 ml/min (1.5x QB)
• Rule of 7 for K • usually 2 K bath (If K HIGH > 6.5-7 mEq/L range, discuss with attending before using 1 K bath
Current CKD Nomenclature Used by KDOQI
Current CKD Nomenclature Used by KDOQI
CKD Categories Definition
CKD CKD of any stage (1-5), with or without a kidney transplant, including both
non–dialysis-dependent CKD (CKD 1-5ND) and dialysis-dependent CKD
(CKD 5D)
CKD ND Non–dialysis-dependent CKD of any stage (1-5), with or without a kidney
transplant (ie, CKD excluding CKD 5D)
CKD T Non–dialysis-dependent CKD of any stage (1-5) with a kidney transplant
Specific CKD Stages
CKD 1, 2, 3, 4 Specific stages of CKD, CKD ND, or CKD T
CKD 3-4, etc Range of specific stages (eg, both CKD 3 and CKD 4)
CKD 5D Dialysis-dependent CKD 5
CKD 5HD Hemodialysis-dependent CKD 5
CKD 5PD Peritoneal dialysis–dependent CKD 5
adequacao
- fluxo de sangue adequado
- dialisador koa
- tempo de dialise
- frequencia de dialise
- fluxo do dialisato
- tamanho d agulha
- anticoagulacao adequada
