ICUIdea

Eveniment imun legat de administrarea de heparina ce determina TROMBOCITOPENIE si potetial tromboza

SCOR 4Ts indica probabilitatea de HIT

1. TROMBOCITOPENIA

0	– ↓ cu > 30% a numarului de trombocite (< 10×109/l)
1	– ↓ cu 30 – 50 % a numarului de trombocite (10 – 19×109/l)
2	– ↓ cu > 50% a numarului de trombocite (< 20×109/l)

2. TIMP

0	– la ⋜ 4 zile fara expunere recurenta la heparina
1	– 5-10 zile (neclar) – > 10 zile – ⋜ 1 zi + expunere la heparina in urma cu 30-100 zile
2	– 5-10 zile (clar) – ⋜ 1 zi + expunere la heparina in urma cu ⋜ 30 zile

3. TROMBOCITOPENIE

0	– fara
1	– tromboze in progresie sau recurent – piele eritematoasa la nivelul injectarii heparinei
2	– tromboze noi  – piele necrozata – reactie acuta sistemica postinjectare de heparina

4. ALTE CAUZE DE TROMBOCITOPENIE

0	Definite
1	Posibile
2	Fara

Scor 4 Ts 

⋝ 6 – Risc mare

4-5 Risc intermediar

⋜ 3 Scazut

HIT	TIP I	TIP II
Mecanism	Non imun (direct)	Non imun (direct)
Incidenta	10 – 20%	1 -3% UFH (10x ↓ in LMWH)
Onset	1 – 4 zile	5 – 10 zile (mai devreme in exp)
Nadir	> 100k	> 20k (aprox 60k)
Sequel		Trombotic Hemoragic
Management		D/C Heparit alt A/C cel putin 4 sapt

Tip 2 → IgG leaga complex Heparina – pF4 → Deactivare trombocite → Eliberare PF4 → Status hiperoagulant, consum trombocite → Trombocitopenie 

DIAGNOSTIC: 4TScore + SRA (Serotonin Release Assay)

Alternative de tratament:

• IV 
  • Argatoban – NU in insuficienta hepatica
  • Bivalirudin – NU in insuficienta renala
• SC
  • Danaparoid
  • Fondaparinux – NU in insuficienta renala
    • Tratament TEP/TVP
      • < 50 kg – 5 mg SC/zi
      • 50-100 kg – 7.5 mg SC/zi
      • > 100 kg –  10 mg SC/zi
    • Profilaxie
      • 2.5 mg/zi > 50 kg

Imunoglobuline IV – inhiba legarea Ac antiPF4/heparin de FcR plachetar

NU se administreaza trombocite !!! – doar in urgente