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Disseminated intravascular coagulation
(DIC)
Jørn Dalsgaard NielsenThrombosis CentreGentofte Hospital
Denmark
Characteristics of DIC
Arterial thrombosis
Venous thrombosisDIC
Introduction
• Thrombotic microangiopathy (TMA) and disseminated intravascular coagulation (DIC) are disorders causing obstruction of the microvascular circulation
Trombotic
microangiopathy
Increased platelet aggregation
DIC
Increased fibrin formation
Thrombotic microangiopathy
Trombotic
microangiopathy
Increased platelet aggregation
TTP HELLP HUS
TTP: Thrombotic Thrombocytopenic Purpura
HELLP: Haemolysis, Elevated Liver enzymes, Low Platelets
HUS: Haemolytic Uremic Syndrome
Type Symp. Etiology
TTP: CNS vW cleaving factor deficiency, cong/aquired
HELLP: Liver Pregnant women
HUS: Kidney +/- diarrhoea associated (E coli 0157)
Trombotic
microangiopathy
Increased platelet aggregation
TTP HELLP HUS
Thrombotic microangiopathy
Trombotic
microangiopathy
Increased platelet aggregation
TTP HELLP HUS
Treatment: TTP HELLP HUS
• Eliminate the causal factor +
• Plasmapheresis (or FFP or cryosupernatant transfusion) +
• Corticosteroids (+) + (+)
• IV gamma globulin (+) (+)
• Rituximab + (+)
• Avoid platelet transfusions + + +
Thrombotic microangiopathy
Criticalillness
DIC is a complication
Banal
Seriousillness
Causes of DIC
SepsisOther causes
The Vicious Cycle of Inflammation and
Coagulation
SepsisSepsisSepticSepticshockshock
SevereSeveresepsissepsis
The Vicious Cycle of Inflammation and
CoagulationInfectionInfection
InflammationInflammation
CoagulationCoagulation
InflammationInflammation
CoagulationCoagulation
InflammationInflammation
CoagulationCoagulation
Endothelial Endothelial DysfunctionDysfunction
IschemiaIschemiaOrgan FailureOrgan Failure
DeathDeath
InflammationInflammation
Esmon. Esmon. Immunologist.Immunologist. 1998;6:84. 1998;6:84.
Progression of SEPSISProgression of SEPSIS
MonocytesEndothelial
cells
Cytokines
Endothelial cells
Tissue factor
Activation of coagulation Thrombin Fibrin
Platelets
Leuko-cytes
Non-adhesive surfaceA
dhesive surface
Accelerates coagulation
THE ”CLASSIC” COAGULATION SYSTEM
Surface contact Tissue factor
XII XIIa
XI XIa
IX IXa
X Xa X
II IIa
I Ia (fibrin)
Phospholipid, Ca++, VIII
Phospholipid, Ca++, V
VIIa VII
Ca++
APTT Prothrombin time
EXPRESSION OF TISSUE FACTOR
CONSTITUTIVE
e.g.:epithelial cellsglial cells
INDUCED
e.g.:monocytic cellsendothelial cells
PROHIBITED
e.g.:lymphocyteserythrocytes
IL-1TNF-C5a
Endothelial dam
age
Haemostatic
mechanisms
SYSTEMIC INFLAMMATION
TF
TF
TF
MonocyteActivation of monocytes
TF
TF
Cytokines
Intravascularclot formation
NORMAL HAEMOSTASIS
Activatedmonocyte
Causes of DIC (mechanisms)
• Extensive release of tissue factor• Increased formation of tissue factor• Abnormal activators of coagulation • Contact activation hypotension
Causes of DIC (Clinical conditions, I)
• Infections• Sepsis
– Gram negative (endotoxin)– Gram positive (polysaccharides, peptides)
• Viremias– Varicella– Hepatitis– Cytomegalovirus– HIV
Causes of DIC (Clinical conditions, II)
• Trauma• Crush injuries• Other trauma with tissue necrosis• Severe burns• Extensive surgery
• Obstetric complications• Amniotic fluid embolism• Placental abruption• (Pre)eclampsia• Dead fetus syndrome
Causes of DIC (Clinical conditions, III)
• Hemolysis• Hemolytic transfusion reactions• Massive transfusions• Malaria• Other severe hemolysis
• Malignant disorders• Metastatic malignancy• Tumors producing cancer procoagulant• Tumor with tissue necrosis
Causes of DIC (Clinical conditions, IV)
•Vascular abnormalities• Giant hemangioma• Heriditary teleangiectasis• Prosthetic devices
– Aortic balloon assist devices– Denver shunts
• Other conditions• Pancreatitis• Acute liver necrosis• Transplant rejection• Heat stroke
Progression of DIC
TimeOnset of DIC
Systemic fibrin formationSystemic inflammation
Multiple organ dysfunction
Systemic bleeding
Progression of DIC
TimeOnset of DIC
Systemic fibrin formationSystemic inflammation
Multiple organ dysfunction
High fibrinolytic activity
Abr
upt o
nset
of D
IC
Systemic bleeding
Low fibrinolytic
activity
Examples of hyperfibrinolytic DIC
• DIC in women with post-partum bleeding
• DIC in patients with promyelocytic
leukaemia
• Early after severe trauma
• Contact with Lonomia caterpillars
Thrombin- and stasis-induced release of tissue plasminogen activator
Fibrinolytic activity in patients with DIC
Abr
upt o
nset
of D
IC
Plasminogen Plasmin
Fibrin Fibrin degradation products
Plasminogenactivator
inhibitor-1
2-Plasmin inhibitor
During DIC FXII FXIIa PrekallikreinKallikrein
PC APC inhibits PAI-1
Hyper- and non-hyperfibrinolytic DIC
• Hyperfibrinolytic DIC– Main problem: Severe bleeding
• Non-hyperfibrinolytic DIC– Main problem: Microvascular occlusion
• DIC in septic patients is a
non-hyperfibrinolytic type of DIC
TF and LPS induced DIC
DIC was induced in rats by infusion of TF or LPS
TF LPS p
Platelets *109/l 204 177 ns
Fibrinogen mg/dl <50 <50 ns
TAT ng/ml 162 170 ns
D-dimer g/ml12,4 1,2 0,001
PAI U/ml 22 245 0,001
Glomerular fibrin 12% 73% 0,001
Asakura et al. Crit Care Med 2002; 30: 161-4
Clinical manifestations
of DIC
Symptoms of DIC
• Dysfunction of multiple organs– The pulmonary microembolism syndrome
• Acute: vascular and bronchial constriction• Late: ARDS
– Acute renal failure• Oliguria, increasing serum creatinine,
haematuria– Cerebral dysfunction
• Confusion, blurred consciousness, coma– Cutane haemorrhagic necroses– Failure of liver, endocrine glands etc.
Diagnostic criteria of DIC
MODS
SIRSDIC
IschaemiaIschaemia DestructionDestruction
ModificationModification(Amplification)(Amplification)
Local haemostatic response to an injury
Local immunological response to an injury
Circulating mediators
Circulating mediators
SIRS+DIC = hyperproteolysisSIRS+DIC = hyperproteolysis
CoagulationCoagulation
FibrinolysisFibrinolysis
ComplementComplementKininesKininesCytokinesCytokines
BLOOD TESTS WHEN DIC IS SUSPECTED
Simple screening
Extended screening
Supplementary tests
Platelet count
Activated partial thromboplastin time (APTT)
Prothrombin time (PT)
Fibrin D-dimer fragment
Fibrinogen
Antithrombin
Further evidence for activation of coagulation
and fibrinolysis
Activation of coagulation
Prothrombin
THROMBIN
Antithrombin
Thrombin-Antithrombin
complex(TAT)
Fibrinogen
PlasminFibrin
FXIII FXIIIa
D fragmentsE fragments
D dimerE fragments
Fragment 1+2
Cross-linkedfibrin
Fibrino-peptideA + B
Soluble fibrin monomer as predictor for DIC in neonatal sepsis
• Healthy neonates: 24,5 ± 6,09 mg/l• Sepsis, no DIC: 33,7 ± 11,9 mg/l• Sepsis + DIC*: 73,2 ± 31,6 mg/l
Critical level: 48,5 mg/l
Sensitivity: 100%
Specificity: 93%
Overall accuracy: 97,5%Selim et al. Haematologica 2005;90:419-20
*ISTH DIC score 5
SCHISTOCYTES
THROMBUSFIBRIN
Longitudinally cut blood vessel
Definition of disseminated
intravascular coagulation
ISTH´s Scientific Subcommittee on DIC, July 2001
DIC is an acquired syndrome characterized by the intravascular activation of coagulation with loss of localization arising from different causes. It can originate from and cause damage to the microvasculature, which if sufficiently severe, can produce organ dysfunction
Scoring system for overt DIC
• Platelet count– (>100=0, <100=1,
<50=2) ..............................• Soluble fibrin/D-dimer
– (normal=0, =2, =3) .............................• Prolongation of PT
– (<3s=0, 3-6s=1, >6s=2) ................................• Fibrinogen
– (>1g/l=0, <1g/l=1) ..........................................
• Calculate sum ........................................
ISTH´s Scientific Subcommittee on DIC, July 2001
YES NO
stopcontinue
• Underlying disorder known to be associated with overt DIC
Scoring system for overt DIC
• Platelet count– (>100=0, <100=1,
<50=2) ..............................• Soluble fibrin/D-dimer
– (normal=0, =2, =3) .............................• Prolongation of PT
– (<3s=0, 3-6s=1, >6s=2) ................................• Fibrinogen
– (>1g/l=0, <1g/l=1) ..........................................
• Calculate sum ........................................
ISTH´s Scientific Subcommittee on DIC, July 2001
YES NO
stopcontinue
• Underlying disorder known to be associated with overt DIC
Polytrauma
85 1
8 3
+3 1
2,2 0
5
- Example -
Scoring system for overt DIC
• If the calculated score is 5: compatible with
overt DIC repeat scoring daily
– <5: suggestive (not affirmative) for non-overt DIC repeat next 1-2 days.
ISTH´s Scientific Subcommittee on DIC, July 2001
Scoring system for non-overt DIC• Presence of underlying disorder
– (no=0, yes=2) .......................................................... • Platelet count + changes
– (100=0, <100=1) + (=-1, stable=0, =1) .......• Sol.fibrin/D-dimer + changes
– (normal=0, =1) + (=-1, stable=0, =1) ........• Prolongation of PT + changes
– (3s=0, >3s=1) + (=-1, stable=0, =1) ...........• Antithrombin
– (normal=-1, low=1) .................................................• Protein C
– (normal=-1, low=1) .................................................• TAT complexes
– (normal=-1, high=1) .................................................
• Calculate sum ................................................
ISTH´s Scientific Subcommittee on DIC, July 2001
Validation of the ISTH scoring system for overt DIC
Distribution of DIC scores in 217 patients in intensive care unit
Bakhtiari et al. Crit Care Med 2004; 32:2416 –2421
Validation of the ISTH scoring system for overt DIC
Bakhtiari et al. Crit Care Med 2004; 32:2416 –2421
Validation of the ISTH scoring system for non-overt DIC
Non-overt DIC scores in 490 patients in intensive care unit
Toh & Downey. Blood Coagul Fibrinolysis 2005;16:69–74
Survivors
Deaths
Validation of the ISTH scoring system for non-overt DIC
Toh & Downey. Blood Coagul Fibrinolysis 2005;16:69–74
Validation of the ISTH scoring system for non-overt DIC
• The mortality rate for non-overt DIC was – 29% (105 of 360) for scores below 5 – 78% (70 of 90) for scores of 5 or above
• The mortality rate for overt DIC was also 78% (38 of 49).
• The non-overt DIC scoring template is workable and has prognostic relevance.
• A score of 5 and greater is recommended as diagnostic of non-overt DIC.
Toh & Downey. Blood Coagul Fibrinolysis 2005;16:69–74
Scoring system for overt DIC
• Platelet count– (>100=0, <100=1,
<50=2) ..............................• Soluble fibrin/D-dimer
– (normal=0, =2, =3) .............................• Prolongation of PT
– (<3s=0, 3-6s=1, >6s=2) ................................• Fibrinogen
– (>1g/l=0, <1g/l=1) ..........................................
• Calculate sum ........................................
ISTH´s Scientific Subcommittee on DIC, July 2001
YES NO
stopcontinue
• Underlying disorder known to be associated with overt DIC
A low cutoff of 1 mg/l was used by:
1.Dempfle et al. Thromb Haemost 2004; 91: 812–82.Toh et al. Blood Coagul Fibrinolysis 2005; 16: 69-743.Angstwurm et al. Crit Care Med 2006; 34: 314–20
D-dimer- low cutoff -
Interassay variation of
D-dimer
D-dimer was determined in 39 plasma samples with 23 D-dimer assays
Dempfle et al. Thromb Haemost 2001; 85: 671–8
D-dimer tests giving comparable results
BioMérieux Vidas D-dimer
BioMérieux MDA D-dimer
Suggested cutoffs:
Low: 1 mg/l
High: 4 mg/l
Roche Cardiac D-dimer
Roche Tinaquant
Stago Liatest D-Di
Low HighWada et al. (2003) Dia-Iatron, LPIA-FDP 10 40 n.d./532 n.d./752 -Dhainaut et al. (2004) Stago, Liatest D-Di 0.4 4.0 166/454 = 37% 273/1114 = 25% 1.5Bakhtiari et al. (2004) BioMérieux, Vidas D-dimer 0.4 4.0 33/74 = 45% 36/143 = 25% 1.8
Dempfle et al. (2004)
BioMérieux, MDA D-dimerRoche, Tinaquant D-dimerIatro, SF
1.00.92.6
3.33.15.0
11/31 = 36%11/28 = 39%16/32 = 50%
47/301 = 16%47/304 = 16%42/300 = 14%
2.32.43.1
Toh et al. (2005) BioMérieux, MDA D-dimer 1.0 4.0 38/49 = 78% 105/360 = 29% 2.7
Sivula et al. (2005) Roche, Tinaquant D-dimer 2.0 8.0 38/95 = 40% 65/399 = 16% 2.5
Kienast et al. (2006) n.d. 0.4 4.0 12/42 = 29% 74/334 = 22% 1.3Angstwurm et al. (2006) BioMérieux, MDA D-dimer 1.0 5.0 15/28 = 54% 41/205 = 20% 2.7
Cauchie et al. (2006)
Stago, Liatest D-DiStago, FS testStago, FDP Plasma
n.d.n.d.20.0
n.d.n.d.40.0 18/32 = 56% 30/116 = 26% 2.2
Voves et al. (2006)Stago, Asserachrom D-DimerRoche, Enzymune-Test FM
0.92.6
3.15.0
6/10 = 60%7/12 = 58%
7/30 = 23%6/28 = 21%
2.62.8
Assay DIC No DICStudy Ratio
28-day MortalityFibrin-related markerCut-off (ug/ml)
Cut-off levels of fibrin related markers
Cut-off levels of D-dimerInfluence of low cut-off level of D-dimer on mortality
y = 0,7877Ln(x) + 2,3628
R2 = 0,7239
0,0
0,5
1,0
1,5
2,0
2,5
3,0
3,5
0,0 0,5 1,0 1,5 2,0 2,5
Cut-off level (mg/l)
Mo
rtal
ity
rati
o (
DIC
/No
DIC
)
The ATryn Study
Clinical Study Protocol
Exploratory efficacy and safety, pharmacokinetics and dosefinding study of recombinant human antithrombin in patients with disseminated intravascular coagulation associated with severe sepsis
Calculation of overt DIC score
Calculation of non-overt DIC
score
<
Treatment of DIC
PAR-1 NFB
T
TM
PC EPCR
TM
PC EPCR
TM
PC EPCR
TM
PC EPCRA
A
A
A
A
A
A
A
hrombin-signalingEndothelial cell
From normal haemostasis to sepsis
PAR-1 NFB
T
T
TM
PC
TM
PC
A
A
A
A
hrombin-signaling in sepsisEndothelial cell
T
T
T
A
T
T
T
T
T
T
T
CytokinesAdhesionmolecules
PAR-1 NFB
EPCR
EPCR
EPCR
EPCR
T
T
T
T
T
T
T
PAR-1 NFB
T
T
TM
PC
TM
PC
A
A
A
A
hrombin-signaling in sepsisEndothelial cell
T
T
T
A
CytokinesAdhesionmolecules
PAR-1 NFB
EPCR
EPCR
EPCR
EPCR
A
A
A T
T
T
T
T
T
T
Heparin
Elastase
T
T
T
T
T
T
Pulletz et al. Crit Care Med 2000; 28: 2881-6. Jordan et al. Am J Med 1989; 87 Suppl 3B: 1989
Treatment with heparin
PAR-1 NFB
T
T
TM
PC
TM
PC
A
A
A
A
hrombin-signaling in sepsisEndothelial cell
T
T
T
A
CytokinesAdhesionmolecules
PAR-1 NFB
EPCR
EPCR
EPCR
EPCR
A
A
A T
T
T
T
T
T
T
Heparin
Elastase
T
T
T
T
T
T
A
A
A
A
A
TT
TT
TT
Treatment with heparin and antithrombin
PAR-1 NFB
T
T
TM
PC
TM
PC
A
A
A
A
hrombin-signaling in sepsisEndothelial cell
T
T
A
PAR-1
EPCR
EPCR
EPCRA
A
A T
T
T
T
T
T
T
Heparin
Elastase
T
T
T
T
T
T
A
A
A
A
A
TT
TT
TT
APC
APC
EPCR
T
Treatment with activated protein C +/- heparin
Role of heparin in sepsis
Echtenacher et al.
Infect Immun 2001; 69: 3550-5
Heparin treatment after cecum ligation and puncture increases mortality in rats (13% 75%, p < 0.015).
CLP+PBS
CLP+heparin
Heparin treatment after cecum ligation and puncture
The role of heparin in sepsis
Schiffer et al. Crit Care Med 2002; 30:2689 –2699
A DIC model:
22 sheeps had intravenous infusion of E. coli endotoxin
The role of heparin in sepsis
Cornet et al. Thromb Haemost 2007; 98: 579–586
A meta-analysis of animal studies
The role of heparin in sepsis
Cornet et al. Thromb Haemost 2007; 98: 579–586
LPS studies
LPS studies
N=2x5E. Coli antiserum
Dunn et al. 1983
Two studies showing negative effect of heparin were not included in the meta-analysis:
Corrigan et al. J Infect Dis 1975;131: 139–143. Echtenacher et al. Infect Immun 2001; 69: 3550-5
Role of heparin in sepsis
• Heparin seems to have:
– a beneficial effect in animal models where DIC is induced by endotoxin – probably due to the anti-inflammatory effect of binding and neutralisation of TNF
– a harmful effect when given to septic animals containing living bacteria.
Severe sepsis inducessystemic capillary leak
Sepsis-induced capillary leak syndrome
Decreased plasma activity of AT and PC in septic patients with DICAsakura et al. Eur J Haematol 2001; 67: 170-5
• Among 139 septic patients the 68 patients with DIC had significantly higher levels of TAT and lower levels of AT and PC than the 71 patients without DIC (p<0.001 for all variables) but no significant correlation was observed between plasma levels of TAT and AT or between plasma levels of TAT and PC.
• When the patients were classified into three groups according to the albumin level, no significant differences in AT activity or PC activity were observed between the patients with and without DIC.
Decreased plasma activity of AT and PC in septic patients with DICAsakura et al. Eur J Haematol 2001; 67: 170-5
The results suggest that the reduced activity of AT and PC is not due to consumption coagulopathy but rather to capillary leak, degradation by elastase, and/or reduced synthesis.
Dual-chamber system to analyze endothelial cell layer permeability
Endothelial cell layer
Polycarbonate membrane of 3µm pore size
Evans blue-labelled bovine serum albumin
Upper 500 µl chamber for addition of test material
Lower 1500 µl chamber for collection of media to be analyzed for Evans blue labelled bovine serum albumin (OD at 650 nm)
Feistritzer & Riewald. Blood 2005; 105: 3178-84
Endothelial barrier protection by activated protein C through PAR1-dependent
sphingosine 1–phosphate receptor-1 crossactivation
Feistritzer et al. Blood. 2005;105:3178-84
PAR1-dependent signaling by the interdependent procoagulant and anticoagulant proteases thrombin and APC can have opposite effects on endothelial barrier integrity. Barrier protection by APC or low concentrations of thrombin is mediated by sphingosine kinase-1 activity and crossactivation of S1P1 signaling.
APC reduces the mortality of LPS-induced endotoxemia in mice
APC
Saline
Kerschen et al. J Exp Med. 2007;204:2439-48
APC reduces the mortality of LPS-induced endotoxemia in mice
APC
Saline
EPCR / mice
- No effect in EPCR / mice -
Kerschen et al. J Exp Med. 2007;204:2439-48
APC reduces the mortality of LPS-induced endotoxemia in mice
APC
Saline
PAR1 -/- mice
- Reduced effect in PAR1 -/- mice -
Kerschen et al. J Exp Med. 2007;204:2439-48
APC reduces the mortality of LPS-induced endotoxemia in mice
5A-APC 2, 10 g
Saline
- and so does 5A-APC -5A-APC: A recombinant APC variant with normal signaling but <10% anticoagulant activity
Kerschen et al. J Exp Med. 2007;204:2439-48
Sepsis and DIC
• Septic patients may develope DIC as a result of activation of Toll-like receptors (TLRs) on monocytes, neutrophils and endothelial cells by microbial products like lipopolysaccharides, peptidoglycan, and lipoteichoic acid.
Zhang & Ghosh. J Clin Invest 2001; 107: 13-19
Henneke & Golenbock. Crit Care Med 2002; 30 Suppl: 207-13
TLR-mediated activation of
NFB
Zhang & Ghosh.
J Clin Invest 2001; 107: 13-19
Role of NFB in sepsis
Böhrer et al. J Clin Invest 1997; 100: 972-85
NFB in nuclear extracts from peripheral blood mononuclear cells is comparable to the APACHE-II score as a predictor of outcome in septic patients.
APC inhibits activation of NFB
Esmon CT. J Autoimmun 2000; 15 113-6:
• Activated protein C reduces nuclear translocation of NFB resulting in reduction of cytokine synthetic rates.
Antiinflammatory effects of APC
• APC blocks cytokine elaboration by mononuclear cellsGrey et al, J Immunol 1994;153:3664 –68
• Endothelial Protein C ReceptorFukudome & Esmon, J Biol Chem 1994;269:26486-91
• Mononuclear Phagocyte Protein C ReceptorHancock et al, Transplantation 1995;60:1525-32
Anti-inflammatory effects of AT
• Binding to endothelium stimulates prostanoid release– Yamauchi et al. BBRC 1989– Horie et al. Thromb Res 1990
• Increased prostacyclin levels in animal models – Uchiba et al. Thromb Res 1995 – Uchiba et al. Am J Physiol 1996
• Inhibition of endotoxin-induced cytokine synthesis, platelet aggregation, leukocyte differentiation and vascular permeability by prostacyclin – Uchiba et al. Thromb Res 1996
• Reduction of ischemia-reperfusion injury– Ostrovsky et al. Circulation 1997– Harada et al. Blood 1999
Anti-inflammatory effects of AT
• Inhibition of IL-6 and tissue factor release from endothelial cells and monocytes– Souter et al. Crit Care med 2001
• Inhibition of endothelial cell proliferation– Larson et al. J Biol Chem 2001
• ICAM-1-dependent inhibition of adhesion of neutrophils to endothelial cells– Kaneider et al. Ann Hematol 2003
• Inhibition of NFB activation in endothelial cells and monocytes– Mansell et al. FEBS Lett 2001 – Oelschlager et al Blood 2002
• Effect on endothelial-leukocyte interactions in endotoxemia exerted predominantly via the endothelium– Mizutani et al. Blood 2003
AT inhibits LPS-induced activation of NFB
Mansell et al. FEBS Letters 2001; 508: 313-7:
• LPS-induced, TLR4-mediated activation of NFB in human mononuclear cells was inhibited dose-dependently by AT.
• Modified AT without serpin activity had no effect.
• The effect was not increased by addition of heparin.
AT inhibits LPS-induced TF and IL-6 production by mononuclear cells, endothelial cells, and whole blood
• TF and IL-6 were determined after stimulation of whole blood, HUVEC, and MNC with LPS for 4-6 hours.
• Production of TF and IL-6 was reduced in the presence of varying concentrations of AT.
Souter et al. Crit Care Med 2001; 29: 134-9
� IL-6
TF
AT prevents LPS-induced pulmonary vascular injury
Uchiba & Okajima. Semin Thromb Haemost 1997; 23:583-90:• Intravenous administration of AT (250 U/Kg) to rats
prevented LPS-induced accumulation of leukocytes and increases in pulmonary vascular permeability.
• Trp49-modified AT, which lacks affinity for heparin, had no effect.
• AT had no effect in animals pretreated with indomethacin, suggesting that the protective effect was a result of endothelial release of prostacyclin.
• Inhibition of thrombin formation by inactive FXa did not prevent pulmonary vascular injury
Prevention of vascular leakage during sublethal porcine sepsis by antithrombin
Dickneite, G & Kroez, M
• Sepsis was induced in 18 pigs by a 3 hours infusion of LPS 0,25 g/kg/h.
• 90 minutes after start of LPS infusion the animals were randomised to:– AT 120 IU/kg iv bolus + 5 IU/kg/h iv infusion
– AT 250 IU/kg iv bolus + 10 IU/kg/h iv infusion
– Placebo (HSA)
Presented at the 13th Annual Congress of ESICM in Rome, 1-4 October 2000
Prevention of vascular leakage during sublethal porcine sepsis by antithrombin
Dickneite, G & Kroez, M
• The broadening and dispersal of interlobular connective tissue was decreased significantly and dose-dependently by AT.
• Also the periportal edematisation and accumulation of leukocytes could be reduced.
Presented at the 13th Annual Congress of ESICM in Rome, 1-4 October 2000
Conclusion:
Effect of AT on DIC in man- the first randomised study -
• 51 patients with DIC were randomised to substitution with– AT infusion, target: 100%– Heparin infusion, 3000 IU as bolus + 300 IU/h– AT + reduced dose of heparin (1000 IU + 100 IU/h)
• Conclusion:– AT reduced duration of DIC– Concomitant heparin caused:
• Acccelerated reduction of platelet count
• Increased consumption of AT
• Increased need of blood transfusion
Blauhut et al. Thromb Res 1985; 39: 81-9:
Randomised trials on the use of AT in patients with sepsis or evidence of DIC
Study Patients Treatment ControlBlauhut (1985) 51 AT(+Hep) HepVinazzer (1989) 133 AT HepInthorn (1993) 40 AT+Hep HepFourrier (1995) 32 AT PlaceboSchuster (1995) 42 AT+Hep HepEisele (1998) 42 AT PlaceboBaudo*(1998) 56 AT Placebo*Subgroup analysis
Randomised trials on the use of AT in patients with sepsis or evidence of DIC
0,0 1,0 2,0
0,37 (0,15-0,88)
0,43 (0,20-0,92)
0,63 (0,28-1,39)
AT vs. Hep (N = 133)
AT vs. Placebo (N = 130)
AT+Hep vs. Hep (N = 150)
Mortality odds ratio
AT reduces mortality significantly when used alone but not when accompanied by heparin treatment
Randomised trials on AT replacement in intensive care management of patients
with an antithrombin activity below 70%
0,0 1,0 2,0 3,0 4,0
Harper (1991)
Albert (1992)
Diaz-Cremadez (1994)
Baudo (1998)
Waydhas (1998)
Total
Odds ratio
0,85 (0,51-1,73)
Mortality
KyberSept Study KyberSept Study
A phase 3 trial of antithrombin versus placebo in patients with severe sepsis or septic shock.
The trial was powered to detect a 15% reduction of an expected placebo 28-day mortality of 45%.
2339 patients were randomised. In the treatment group the mean increase in plasma antithrombin at 24 hours of inclusion was 130%.
Mortality was lower than expected and almost identical in the two groups (Antithrombin: 38,9% and placebo: 38,7%).
Warren et al. JAMA 2001; 286: 1869-78
KyberSept StudyKyberSept Study
A shortcoming of the study was that use of unfractionated or LMW heparin 10.000 IU was allowed without randomisation.
Less than a quarter of the patients in the study had no heparin.
Heparin increased the risk of poor outcome and adverse bleeding.
Warren et al. JAMA 2001; 286: 1869-78
KyberSept StudyKyberSept Study
Warren et al. JAMA 2001; 286: 1869-78
KyberSept: No Hep. N = 698
Placebo 43,6%Antithrombin 37,8%
Difference: 5,8%
p = 0,08
28-day mortality:
Randomised trials on the use of AT in patients with sepsis or evidence of DIC
0,0 1,0 2,0
0,37 (0,15-0,88)
0,72 (0,55-0,96)
1,09 (0,89-1,32)
AT vs. Hep (N = 133)
AT vs. Placebo (N = 828)
AT+Hep vs. Hep (N = 1766)
Mortality odds ratio
AT reduces mortality significantly when used alone but not when accompanied by heparin treatment
KyberSept results included:
Effects of activated protein C
• inhibits leukocyte-endothelial cell interaction
• inhibits thrombin formation
• increases fibrinolytic activity
*Bernard GR et al. N Engl J Med 2001; 344: 699-709
Protein S
FVIIIa
FVa
Endothelial cell
Activation of protein C
ThrombomodulinProtein C
Thrombomodulin
Activatedprotein C
ThrombinEPCR
PAI-1 TAFI
Protein C in septic patients
• The plasma concentration of PC is reduced in septic patients due to– Capillary leak
– Degradation by elastase
– Decreased synthesis
– Increased consumption during DIC
• Activation of PC is compromised in septic patients because the endothelial expression of thrombomodulin and endothelial protein C receptor is suppressed
The PROWESS Study
Protein C Worldwide Evaluation in Sepsis
• Clinical controlled phase III multicenter
double-
blind placebo-controlled trial in severe
sepsis
Bernard GR et al. N Engl J Med 2001; 344: 699-709
PROWESS Study DescriptionPROWESS Study Description• Design
– Randomized, double-blind, placebo-controlled trial– 11 countries at 164 sites
• Population - Severe Sepsis– Presence of a known or suspected infection– Evidence of a systemic response to the infection (3 SIRS
criteria)– At least one sepsis-associated organ dysfunction of no greater
than 24 hours duration
• Treatment Arms– 1:1 randomization to Drotrecogin Alfa (activated) 24
µg/kg/hr or placebo for 96 hours
Data from the PROWESS TrialData from the PROWESS Trial
PROWESS Study DesignPROWESS Study DesignInfection with organ failureInfection with organ failure
Start of study drugStart of study drug infusion infusion
48 Hours Maximum - Consent - Start Drug
End of 96 hour infusion of study drugEnd of 96 hour infusion of study drug
Assessment of 28-dayAssessment of 28-dayall-cause mortalityall-cause mortality
Alive or Dead?Alive or Dead?
Routine Patient Care
Data from the PROWESS TrialData from the PROWESS Trial
ResultsResults Drotrecogin Alfa (activated) in patients with
severe sepsis:– Acceptable safety profile– Significantly reduces mortality
• 6.1% absolute, 19.4% relative risk reduction
• Lower mortality observed across most subgroups
Number needed to treat to save one additional life equals 16
Treatment of sepsis and DIC• Probably the primary goal of DIC treatment should
not be inhibition of coagulation but protection of endothelial cells from being activated to produce inflammatory cytokines and adhesion molecules.
*Okajima et al. Am J Hematol 1991; 36: 265-71
• Increased leukocyte-endothelial cell interaction may be the key mechanism in the development of organ dysfunction.
• Neutropenic patients are unlikely to develope septic ARDS*.
Treatment of sepsis and DIC• Activated protein C (APC) has in addition to its
anticoagulant effect been shown to inhibit leukocyte-endothelial cell interaction
• In the PROWESS trial (N = 1690) 28-days mortality was 6.1% lower in the APC group than in the control group (p < 0.01)*
• AT has EC protective properties when heparin is avoided.
• In the non-heparin groups of the KyberSept trial (N = 698) 28-days mortality was 5.8% lower in the AT group than in the control group (n.s.)**
*Bernard GR et al. N Engl J Med 2001; 344: 699-709
**Warren et al. JAMA 2001; 286: 1869-78
AT
Treatment of sepsis and DIC
• Natural anticoagulant
• Present on EC surface
• EC protective properties:– Inhibits activation of NFB
– Reduces effects of LPS
.
• Natural anticoagulant
• Present on EC surface
• EC protective properties:– Inhibits activation of NFB
– Reduces effects of LPS
.
.
aPC
AT
Treatment of sepsis and DIC
• Natural anticoagulant
• Present on EC surface
• EC protective properties:– Inhibits activation of NFB
– Reduces effects of LPS
• Displaced from EC surface by heparin
• Reduction of mortality in patients with sepsis/DIC not proven in phase III trial
• Natural anticoagulant
• Present on EC surface
• EC protective properties:– Inhibits activation of NFB
– Reduces effects of LPS
• Not displaced from EC surface by heparin
• Reduction of mortality in patients with sepsis/DIC proven in phase III trial
aPC
The face of sepsis
DIC
Systemicinflam-mation