Table of contents :
vital procedures and finally reintroduction into the same (or another)
living organism.
is one of the most important performance parameters of blood pumps. Humans
can clear total doses of up to 14 g of free plasma hemoglobin per day if
their renal function is normal. Free plasma hemoglobin of up to 130 mg/dL
may be bound to form hemoglobin-haptoglobin complexes in vivo. Therefore,
if the plasma hemoglobin level exceeds this value, hemoglobinuria occurs
and leads to organ failure. Currently, comparive in vitro evaluations of
the reported hemolysis effects are difficult due to the lack of uniformity
of the test methods used. In the literature, 3 types of formulas are accepted
as indices of hemolysis. In order to avoid confusion, they are classified
as :
and/or heart surgery
(cava veins => aorta bypass).
It is a pulmonary technology capable of facilitated gas exchange in the
blood, thereby bypassing the alveolar-capillary interface. It consists
of the application of intermediate-term cardiopulmonary bypass for the
treatment of potentially reversible heart and/or lung failure in the neonate,
child, and adult. Applications in the neonate include congenital
diaphragmatic hernia (CDH),
pulmonary
arterial hypertension,
meconium
aspiration syndrome (MAS),
and pre- and post-operative congenital heart
surgery
support. In the older child, myocarditis,
infections,
and respiratory
failure
(RSV
and ARDS)
are the most frequent indications, in addition to peri-operative cardiac
surgical support. ECMO can provide this delivery without causing the iatrogenic
damage associated with high mechanical ventilation pressures, high fraction
of inspired oxygen, or high doses of inotropic medications. Though practitioners
use a multitude of other, more "conventional," therapies for neonatal respiratory
failure, only ECMO has been proven in a randomized, controlled, clinical
trial to improve both mortality and morbidity among neonates. The use of
inhaled nitric oxide (iNO) reduces the necessity for ECMO in newborns and
infants with acute hypoxemic respiratory failure.
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| cellulose diacetate (hollow fiber) | Plasmaflo-AP05H (Asahi Medical, Tokyo, Japan) |
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| Plasmaflo-AP05 (Asahi Medical) |
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| polypropylene (hollow fiber) | Fenwal CPS-10 (Baxter, Deerfield, IL, USA) |
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| Hemaplex-BT900 (Dideco, Mirrandola, MO, USA) |
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| Curesis M82 (Organon Teknika, Durham, NC, USA) |
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| polypropylene (flat plate) | Centry TPE (Cobe, Lakewood, CO, USA) |
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| polysulfone (hollow fiber) | Sulflux-FS (Kaneka, New York, NY, USA) |
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| polymethylmethacrylate (hollow fiber) | Plasmax-PS05 (Toray, Tokyo, Japan) |
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|
or albumin or colloid solution (plasma
exchange (PE))
if they are not replaced with IVIg
with or without polyneuropathy
recipient
=> hyperviscosity
syndrome
and acute renal
failure (ARF))
presensitization-associated
recurrent focal
segmental glomerulosclerosis (FSGS)rejection
: PE removes mercaptans, GABA, phenolic acid, aromatic amino acids, liver
regeneration factors, cerebral activity inhibitors, sodium, potassium,
and ATP. Survival ranges from 18.0ref-30.0ref-33.3ref-37.5ref-66.7%ref
with polyneuropathy
are observed
: ethylene vinyl alcohol and acrylic copolymers may cause mild adverse
reaction in some patients taking ACEI
or Waldenstrom's
disease.
To prevent plugging reverse rinse of the secondary PF is carried. DFPP
is most commonly performed in Japan, but very rarely initiated in the USA.|
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| ethylene vinyl alcohol | Evalfux 2A (Kuraray, Osaka, Japan) |
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IgG, IgA |
| Evalfux 3A (Kuraray) |
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cytokines | |
| Evalfux 4A (Kuraray) |
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IgM, LDL | |
| Evalfux 5A / lipofilter (Kuraray) |
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LDL-C | |
| versapor acrylic copolymer | Cryoglobulin filter (Pall Gelman, Ann Arbor, MI, USA) |
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cryoproteins |
| cellulose diacetate | Plasmaflo-AP06M (Asahi, Tokyo, Japan) |
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cryoproteins |
(plugging is frequent and requires multiple backwashing during the procedures)
(best results at 4°C)
columns removes IgG
pheresis by
and heterozygous who with documented, symptomatic CAD,
hemolytic
anemia,
Staphylococcus
spp. infection and thrombosis at the site of venous access, allergic reactions
leading to anaphylaxis
and activation of coagulation, complement, and fibrinolytic cascades, and
aggregation of platelets. Systemic
arterial hypotension
during plasma exchange is aggravated by the concomitant administration
of ACEI.
During the course of plasma therapy, patients are anticoagulated beacuse
of the loss of platelets and clotting factors removed with plasma. In the
absence of liver dysfunction, clotting factors in the circulation return
to normal within 24 hours.
: sickle cell crises with suspected target organ damage or before major
surgery
: sickle cell crises with priapism
(side effects : thrombocytopenia, protamine-induced systemic
arterial hypotension)
(high costs),
possibly through reduction in high concentrations of these toxins. Although
MARS has been shown to be useful in FHF, its clinical efficacy in subfulminant
hepatic failure and less severe forms of acute liver failure (ALF) remains
uncertain. The current literature also suggests that it may be beneficial
to treat cases of acute-on-chronic liver failure (AoCLF)
(subclavian catheter or internal jugular catheter), which has direct access
to the heart. Using these access sometimes tend to have problems like blocked
catheter from clots or infection at the insertion site. Therefore, extra
care has to be taken with temporary access.
and cephalic vein
at the wrist. Patency = 90% after 1 year, 75% after 4 years
and the cephalic vein,
with patency = 70% after 2 years
and the basilic vein,
with patency = 70% after 2 years
and femoral vein.
and the saphenous vein),
but are of second choice due to higher incidence of thrombosis, infections
and reduced depurative efficiency
– antidecubital vein
– femoral vein
or greater saphenous vein
or the Dialock system for pediatric patients
or concomitant sepsis)
into and removed from the peritoneal cavity as either a continuous (2 L
/ 4 hr) or an intermittent procedure. It has effectiveness similar to hemofiltration.
The dialyzing hyperosmotic solution (Dianeal (PD-2)) contains:,
expecially in diabetic patients,
loss of endogenous protein and amino acids, retroperitoneal
fibrosis,
hyperglycemia
and hypertriglyceridemia
(dialyzing hyperosmotic solution often is glucose- or amino acid-rich and
some pass into liver via portal circulation)
has consistently been associated with a reduced mortality rate in kidney
dialysis patients due to the cholesterol-lowering effects of systemic inflammation
and malnutrition, 2 common complications of dialysis. When dialysis patients
don't have inflammation or malnutrition, hypercholesterolemia predicts
a progressively higher risk deathref
=> renal clear cell
carcinoma.
Other transport activities were also observed in these devices and included
active bicarbonate transport, which was decreased with acetazolamide, a
carbonic
anhydrase II
inhibitor, active glucose transport, which was suppressed with phlorizin,
a specific inhibitor of the sodium-dependent
glucose transporters (SGLTs),
and p-aminohippurate (PAH) secretion, which was diminished with
the SLC22A6 / anion transporter
inhibitor probenecid. A variety of differentiated metabolic functions was
also demonstrated in the RAD. Intraluminal glutathione breakdown and its
constituent amino acid uptake were suppressed with the irreversible inhibitor
of g-glutamyl transpeptidase acivicin; ammonia
production was present and incremented with declines in perfusion pH. Finally,
endocrinological activity with conversion of 25-hydroxy(OH)-vitamin D3
to 1,25-(OH)2 vitD3 was demonstrated in the RAD.
This conversion activity was up-regulated with parathyroid hormone and
down-regulated with increasing inorganic phosphate levels, which are well-defined
physiological regulators of this process in vivoref.
It demonstrates metabolic, immunologic and endocrine activity with systemic
effects in patients with acute
renal failure (ARF)
and multiorgan failure (MOF)ref1,
ref2,
ref3
: it ameliorates cardiac and vascular dysfunction, alters systemic cytokine
abnormalities, and improves survival time in a large animal model of Gram-negative
septic shockref1,
ref2,
ref3.
Hemodialysis and hemofiltration have been important technologies in saving
the lives of patients with ARF and CRF by clearing small solutes from plasma
and thereby preventing death from acidemia, hyperkalemia, volume overload,
and uremia. These therapeutic approaches, however, are still suboptimal,
as patients with ARF have mortality rates exceeding 50%, and patients with
end-stage
renal diseases (ESRD)
have, on average, a life expectancy of 4-5 years. The preeminent cause
of death in patients with ARF is the development of sepsis or the systemic
inflammatory response syndrome with resulting systemic vasodilation, hypotension,
ischemic injury to solid organs, multi-organ failure, and death. This vasodilation
is due to persistent and excessive pro-inflammation. Similarly, the reduced
survival times of patients with ESRD on chronic dialysis have been associated
with a persistent and chronic systemic pro-inflammatory state. The loss
of renal tubule cell mass acutely in acute tubule necrosis and chronically
in ESRD results in an immunologically dysregulated state leading to excessive
pro-inflammationref1,
ref2.
sandwiched between artificial plates or capillaries. The problem is deciding
which liver functions are the most important and shouyld be carried out
by the BAL bioreactor. Biosynthetic capacity is perhaps the least essential
because most proteins synthetised by the liver can be given exogenously
to patients. The generation and detoxification of ammonia is undoubtedly
important. Although an increase in ammonia in the blood is toxic to the
CNS, reduction of ammonia levels per se is not sufficient to alleviate
this toxicity. The enormous scale-up required to use BAL devices clinically
is problematic : at least 1010 hepatocytes in a BAL bioreactor
would be needed to support a patient's failing liver. Sinusoidal endothelial
cells can be expanded to achieve that number. A good vitality of hepatocytes
is maintained for 2-3 weeks, but functions decrease. Encapsulation of hepatocytes
with calcium or sodim alginate gel could reduce immunogenicity and reduce
immune-mediated cytolysis. Freezing and thawing and hepatocytes could store
the material for long times. Modular extracorporeal liver support (MELS)
systems combine biologic liver support with artificial detoxification
technologyref.
),
could potentially provide and alternative source of human hepatocytes.
Although the differentiation of bone marrow derived stem cells into hepatocytes
has been demonstrated in vivo, it has not been achieved in vitro as yet.
However, liver-derived hamatopoietic cells can give rise to cells that
resemble bile duct epithelial cells. Embryonic stem (ES) cells offer
another valuable option, particularly as human ES cell lines are now available.
in the treatment of infertilityref
to induce hypogonadotropic hypogonadism 2 weeks before ovarian stimulation| GnRH analogue (GnRHa) |
|
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|
| GnRH agonist | ||||
| nonapeptides | ||||
| leuprorelin | S.C. | 500-1000 mg/d | ? | yes |
| I.M. depot | 3.75-7.5 mg/mo | ? | yes | |
| buserelin | S.C. | 100-500 mg/d |
|
|
| I.N. | 300-400, 3-4 times daily | yes | ||
| goserelin | S.C. implant | 3.6 mg/mo | ? | seldom |
| histrelin | S.C. | 100 mg/d | ? | no |
| decapeptides | ||||
| nafarelin | I.N. | 200-400 mg 2/d | ? | yes |
| triptorelin | S.C. | 100-500 mg/d | 50 mg/d | yes |
| I.M. depot | 3.75 mg/mo | ? | no | |
| GnRH antagonist | ||||
| cetrotide | S.C. | single dose | 2 mg/injection | yes |
| S.C. | multiple dose | 0.25 mg/d | yes | |
| orgalutran | S.C. | multiple dose | 0.25 mg/d | yes |
-induced
ovulation
may be responsible : melatonin levels naturally cycle in response to light
and dark. Until recently it was thought that melatonin acted only through
the pituitary gland in the brain (this gland is "switched off" during IVF
treatment because it controls a woman's own hormone production, preventing
any activity which could interfere with treatment which artificially stimulates
the ovaries to release an egg), but there are also melatonin receptors
throughout the reproductive system : the hormone may act directly on reproductive
tissues to make women more fertile in lighter months. If you look at the
animal world, it's biologically better for offspring to be born in spring,
so they then get 6-8 months winter comes to develop : the same pattern
had historically been seen in natural human reproduction, but it was less
obvious now because people had more control over deciding when they tried
for a baby, and could use contraception to prevent conception. It has been
observed that there is a seasonal variation, but it has been thought it
might be linked to warmer temperatures in summer months.
monitoring of follicular growth (size and number) : eventually endocrine
monitoring of [17b-estradiol]plasma-assisted
pick-up under general or local anesthesia and 36 hrs after administration
of hCG : on average, of 100 oocytes prelevated (within 10-30'), 90 are
mature and can be surgelated (egg
cryopreservation). Doctors are still figuring out how to do this reliably
without the formation of damaging ice crystals within the eggs, and there
have been fewer than 100 live births using this method. 40 survive treatment
but 4 are damaged. At least 2 US companies, however, already offer women
the chance to freeze their oocytes. Of the remaining 36 eggs, 17 are fertilized
(due to high H2O content the cell membrane becomes stiffer and
fertilization has to be accomplished by microinjection) and only 2 undergo
a correct implantation giving start to normal pregnancies. On average,
3.5 pregnancies are obtained every 100 oocytes prelevated. The average
likelihood of becoming pregnant after one IVF attempt is roughly 20-30%,
and this drops off with age. Doctors have been searching for a way to distinguish
eggs with a high chance of IVF success based on the their shape, genes
or metabolism, but long telomeres could be the secret of success : eggs
with an average telomere length shorter than around 6,300 DNA units never
produce a pregnancy
patient about to undergo chemotherapy and froze it at -196° C. 6 years
later, they thawed 15 fingernail-long strips and grafted them under the
woman's abdominal skin using a local anaesthetic (they feel like beads
under the skin) : transplanting the ovarian tissue back into the patients
is also difficult and there is the danger that the tissue may contain cancerous
cells, but putting the transplant beneath the skin of the abdomen reduces
the health risks and it can be easily removed if necessary. 3 months later,
the woman's hormones prompted the tissue to start making eggs, which the
doctors boosted with fertility drugs. Over 8 months they collected 20 mature
eggs with a needle and mixed 8 of them with sperm for IVF : 2 eggs went
on to form embryos in culture. One was implanted in the woman, but it did
not lead to pregnancyref.
This is not surprising in IVF treatment, where the chances of successful
imp