"Machines and membranes"
Stefano Picca, MD
Department of Nephrology and Urology, Dialysis Unit
“Bambino Gesù” Pediatric Research Hospital, IRCCS
ROMA, Italy
MACHINES AND MEMBRANES:
BASIC NEEDS IN CHILDREN
Machines/circuits:
• Accuracy and precision
• Circuit low priming volume
• Circuit inner pressures and resistance suitable for small catheters use
Membranes:
• Filtration
• Absorption
Dear Tim,
as far as I know this is the first patient treated with CAVH in the
world. We performed this treatment in Vicenza in 1984 and the patient
survived. After that we published the first series of 4 newborns treated
with CAVH (Kidney International 1986) . You made a great deal of
progress since then and even more with this meeting. Best Wishes
Claudio Ronco
• Error up to 12.5%
• 2 pumps (pre-post filter)= error up to 25%
Equaline® Amicon, 1991
Baxter
BM25
Baxter
Aquarius
Baxter- Gambro
Prisma
Baxter- Gambro
Prismaflex
SYNTHETIC MEMBRANES
Symmetric
Asymmetric
(microporous)
Isotropes
Anisotropes
(uniform pores dimension)
(non-uniform pores dimension)
“skin layer” +
highly porous
supportive layer
Skin
REMOVAL OF SOLUTES AND MEDIATORS
Filter cutoff
CONVECTION/DIFFUSION
ABSORPTION
ß2 microglobulin
myoglobin
creatinine
urea
sucrose
ionic compounds
101
inulin
IL-8
Vit B12
102
IL-6
albumin
IL-1
103
TNF
104
105
MW (Daltons)
ABSORPTION
Electrical
Binding
Mechanical
binding
In both cases, absorption depends on:
• Qb
• Quf
• Qd
• Surface
• Initial concentration
Neri, 2012
HEMO(DIA)FILTERS IN NEWBORNS AND CHILDREN: PAST AND PRESENT
MANUF.
FILTER
SURFACE (m2)
MEMBRANE
PRIMING (ml)
Gambro-Hospal
Miniflow10 
0.045
AN69
3.5
Amicon, then
Minntech
Minifilter
0.07
Polysulfone
6
Bellco
Carpediem 1
0.075
Polysulfone
27.2 (circuit)
Bellco
Carpediem 2
0.147
Polysulfone
33.5 (circuit)
Bellco
Carpediem 3 
0.245
Polysulfone
41.5 (circuit)


Baxter-Gambro
HF20
0.2
Polyarylethersulfone (PAES)
60 (kit)
Baxter-Edwards
HF03
0.3
Polysulfone
38
Baxter-Gambro
ST60
0.6
AN69
93 (kit)
Baxter-Edwards
HF07
0.7
Polysulfone
54
Baxter-Gambro
ST100
1.0
AN69
149 (kit)
ACKNOWLEDGEMENTS
• All Dialysis Unit nurses
• All PICU and CICU doctors and nurses
• Tim Bunchman, Stu Goldstein and Claudio Ronco for
precious advices and friendship through the years .
Dialysis Unit, “Bambino Gesù” Pediatric Hospital
Roma, Italy.
Doctor:
S. Picca
Headnurse:
V. Bandinu
Nurses:
N. Avari
D. Ciullo
E. Iacoella
P. Iovine
P. Lozzi
L. Stefani
Nurse Coordinator:
M. D’Agostino