Quiz 7: Dialysis

diffusion and convection

In hemodialysis, solutes are removed by __________ and __________ across a semipermeable membrane.

ultrafiltration

How does the movement of water in hemodialysis occur?

peritoneal membrane

In peritoneal dialysis, the __________ serves as the semipermeable membrane.

dextrose or icodextin or diffusion

The osmotic gradient in peritoneal dialysis is provided by __________ or __________ in the dialysate.

90%

What % of pts use hemodialysis in the US?

10%

What % of pts use peritoneal dialysis in the US?

20-30%

Intradialytic hypotension occurs in approximately _____% of HD sessions.

symptoms of intradialytic hypotension

-dizziness

-cramps

-nausea

-syncope

midodrine

What is the pharmacologic strategy to prevent intradialytic hypotension?

volume overload, RAAS activation, or removal of antihypertensive meds

Intradialytic hypertension can occur due to __________, __________ activation, or removal of __________ during dialysis.

<100 mmHg

Chronic hypotension is defined as a SBP _______ post dialysis and may be treated with Midodrine.

intraluminal instillation of alteplase

How can catheter-related thrombosis be treated with?

vancomycin and cefepime

What does empiric tx of catheter-related infections often includes what?

0.5

The incidence of peritonitis is about _____ episodes per patient-year.

symptoms of peritonitis

-abdominal pain

-N, fever

-cloudy effluent

100; 50%

Diagnosis of peritonitis requires an effluent WBC > _____ cells/mm³ with > _____% PMNs.

-S. epidermidis

-S. aureus

-E. coli

-Pesudomonas

What are the most common causative organisms of peritonitis?

removed; anti-fungal

For fungal peritonitis, the catheter should be __________ and the patient started on __________ therapy.

Mupirocin

Exit-site infection prophylaxis with __________ has been shown to reduce infections

stage 4 (eGFR < 30)

What stage of CKD should you start planning for dialysis initiation?

dialysis

should be initiated in the presence of refractory volume overload, severe hyperkalemia , pericarditis ,encephalopathy, or bleeding complications

5-10

Dialysis is typically initiated when eGFR is between _____ and _____ mL/min/1.73 m² with symptoms.

-size

-solubility

-protein binding

-volume of distribution

What does the dialyzability of a drug depend on?

aminoglycosides and lithium

What 2 drugs are readily removed by dialysis?

digoxin and warfarin

What 2 drugs are poorly removed by dialysis?

supplemental dosing

After HD, _______________ are often required for dialyzable drugs

antibiotics and insulin

In PD, __________ and __________ can be administered intraperitoneally.

indications for hemodialysis

A-metabolic acidosis

E-electrolyte abnormalities (hyperkalemia)

I-intoxications

O-volume overload

U-uremia

-concentration gradient btw blood and dialysate

-molecular size of solute

-membrane surface area

-membrane permeability (pore size)

-blood flow rate

-dialysate flow rate

-temp

What factors affect the rate of diffusion during hemodialysis?

advantages of henodialysis

-efficient removal of toxins and fluid

-effective Cl of larger solutes

-intermittent therapy, less daily burden to pt

-tx is supervised in a clinic

disadvantages of hemodialysis

-requires vascular access

-rapid fluid/electrolyte shifts

-more dietary and fluid restriction

-higher hemodynamic stress

advantages of peritoneal dialysis

-gentle, continuous fluid/electrolyte removal

-better preservation of residual kidney function

-no need for vascular access

-can be done at home (greater independence)

-less dietary/fluid restriction than HD

disadvantages of peritoneal dialysis

-peritonitis risk

-catheter related infection

-requires pt manual dexterity and cleanliness

-can cause weight gain

-possible inadequate dialysis over time

modifiable factors to affect control of peritoneal dialysis

-dialysate volume

-number of exchanges per day

-dwell time

-dialysate concentration

-type of PD (CAPD vs APD)

-hemodynamically unstable pts (cant tolerate HD)

-ICU pts with septic shock, severe fluid overload, or multi organ failure

-pts requiring precise fluid balance

-severe AKI where slow gentle solute removal is preferred

What pts would benefit from continuous renal replacement therapy?

mechanical problems associated with peritoneal dialysis

-catheter obstruction or malpostition

-leaks around catheter site

-hernias

-inadequate drainage/flow probs

-tunnel or exit site infections

-dialysate retention

-Heparin

-erythropoiesis-stimulating agents (ESAs)

-IV iron

-vit d analogues

-phosphate binders

-midodrine

What are the adjunct meds given during hemodialysis?

antibiotics (given directly into dialysate bags)

What meds are given by the peritoneal route during dialysis?