pediatric crrt terms and nomenclature n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Pediatric CRRT Terms and Nomenclature PowerPoint Presentation
Download Presentation
Pediatric CRRT Terms and Nomenclature

Loading in 2 Seconds...

play fullscreen
1 / 18

Pediatric CRRT Terms and Nomenclature - PowerPoint PPT Presentation


  • 137 Views
  • Uploaded on

Pediatric CRRT Terms and Nomenclature. Timothy E. Bunchman. How does dialysis work?. Solute clearance is related to Sieving coefficient Molecular weight of the solute Charge of the solute Gradient across the membrane This can be convective or diffusive.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Pediatric CRRT Terms and Nomenclature' - toviel


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
how does dialysis work
How does dialysis work?
  • Solute clearance is related to
    • Sieving coefficient
      • Molecular weight of the solute
      • Charge of the solute
      • Gradient across the membrane
  • This can be convective or diffusive
solute molecular weight and clearance
Solute Molecular Weight and clearance

Solute (MW) Convective Coefficient Diffusion Coefficient

Urea (60) 1.01 ± 0.05 1.01 ± 0.07

Creatinine (113) 1.00 ± 0.09 1.01 ± 0.06

Uric Acid (168) 1.01 ± 0.04 0.97 ± 0.04*

Vancomycin (1448) 0.84 ± 0.10 0.74 ± 0.04**

Cytokines (large) adsorbed minimal clearance

*P<0.05 **P<0.01

definitions and terms
Definitions and Terms
  • CVVH/CAVH
  • Convective clearance
  • Replacement Solutions
    • Physiologic sterile solution that is either infused pre filter (NA) or post filter (outside of NA) that infused at a set rate (Qr)
convective cavh cvvh
Convective (CAVH/CVVH)

Sterile Replacement

fluid infused into blood

(Qr)

Blood Flow (Qb)

→ → → → → → → → → → → →

BUN 70 mg/dl, K 7 meq/dl, Na 140 meq/d

----↓------------------↓----------------------↓-------

(ultrafiltrate space)

Semi-permeable membrane

Ultrafiltrate (Qef) contains BUN and K of ~ 90% of what was in blood and Na of 140)

definitions and terms1
Definitions and Terms
  • CVVHD/CAVHD
  • Diffusive clearance
  • Dialysate
    • Physiologic sterile solution that is infused countercurrent to the blood flow rate (Qd)
diffusive cavhd cvvhd
Diffusive (CAVHD/CVVHD)

Blood Flow (Qb)

→ → → → → → → → → → → → →

BUN 70 mg/dl, K 7 meq/dl, Na 140 meq/d

----↓------------------↓--------------------------↕---

Bun 0 mg/dl, K 0 meq/dl, Na 140 meq/dl

← ← ← ← ← ← ← ← ← ← ← ← ← ← ←

Dialysis Flow (Qd)

Semi-permeable membrane

Ultrafiltrate (Qef) contains BUN and K of ~ 90% of what was in blood and Na of 140)

definitions and terms2
Definitions and Terms
  • CVVHDF/CAVHDF
  • Convective clearance
    • Replacement Solutions
  • Diffusive clearance
    • Dialysis solution
convective diffusive cavhdf cvvhdf
Convective & Diffusive (CAVHDF/CVVHDF)

Sterile Replacement

fluid infused into blood

(Qr)

Blood Flow (Qb)

→ → → → → → → → → → → → →

BUN 70 mg/dl, K 7 meq/dl, Na 140 meq/d

----↓------------------↓--------------------------↕---

Bun 0 mg/dl, K 0 meq/dl, Na 140 meq/dl

← ← ← ← ← ← ← ← ← ← ← ← ← ← ←

Dialysis Flow (Qd)

Semi-permeable membrane

Ultrafiltrate (Qef) contains BUN and K of ~ 90% of what was in blood and Na of 140)

definitions and terms3
Definitions and Terms
  • SCUF (surgeons can’t understand fluid)
    • Slow continuous ultrafiltration (UF) ultrafiltrate (water and solute) come across the membrane at a rate based upon TMP
  • Transmembrane pressure (TMP)
    • The pressure difference between the blood side and the ultrafiltrate side of the membrane
    • Greater the TMP the greater the UF rate
slide14
SCUF

Blood Flow (Qb)

→ → → → → → → → → → → → →

BUN 70 mg/dl, K 7 meq/dl, Na 140 meq/d

----↓------------------↓---------------------↓--------

Semi-permeable membrane

Ultrafiltrate (Qef) contains solute based upon sieving coefficient

slide15
TMP

Blood TMP = 0 100 100 100

-------------------O--------↓----------------O-----------↑-

Uf TMP = 0 0 100 200

Net TMP 0 100 0 - 100

Semi-permeable membrane

adsorption
Adsorption
  • Concept when solute (e.g. plasma proteins) adhere or get adsorbed to a membrane
  • Commonly discussed with column plasma-adsorption or the “clearance” of cytokines during SIRS
adsorption1
Adsorption

Blood Flow (Qb)

→ → → → → → → → → → → → →

Cytokines seen in SIRS

↓ ↓ ↓

-------------------------------------------------------

Semi-permeable membrane with cytokines adherent

terms and nomenclature conclusion
Terms and NomenclatureConclusion
  • Terminology is confusing and often redundant
  • www.adqi.net paper on Definitions by
    • Gibney, Kimmel and Lazarus