Category: Haem/Onc

COVID-19 Vaccine Induced Thrombosis/Thrombocytopenia (VITT)

Inclusion Criteria [Both of]:

  1. Received AstraZeneca (AZ) COVID 19 vaccination within 28 days (typically 4-28 days from immunisation)
  2. New Onset thrombocytopenia (PLTs <150×109/L) – with or without Thrombosis

Initial Investigations:

  • FBC– specifically to confirm thrombocytopenia <150x 109/L
  • Coagulation screen and D Dimers
  • Blood film to confirm true thrombocytopenia and identify alternative causes

PROBABLE CASE: (ALL 3 criteria)

  1. Received AZ COVID 19 vaccination within 28 days
  2. New Onset thrombocytopenia (PLTs <150×109/L)
  3. D Dimers > 2000 mcg/L

URGENT Scan to confirm the suspected clot.

[If patient doesn’t fit “PROBABLE CASE” proceed to usual treatment]


Condition specific advice:

Central clot:

  • inc. Cerebral Venous Sinus Thrombosis (CVST), Pulmonary Embolis (PE), Splenic, Proximal DVT
  • Discuss with Haematologist
  • Admit Medicine

Suspected DVT (scan unavailable):

  • Treat with Rivaroxaban (Do Not use Dalteparin/LMWH)
  • Request Ultrasound
  • Return AAU Next Day
  • Safety-net Advice

Confirmed Distal DVT (Not above inguinal ligament)

  • Platelets  <100×109/L – Discus with Haematology
  • Platelets ≥100×109/L – Treat as normal

Thrombocytopenia only

  • Platelets  <100×109/L – Discus with Haematology
  • Platelets ≥100×109/L – Treat as normal

Treatment (will be directed by Haematology & Specialist teams):

Avoid:

  • Heparin Based anticoagulants
  • Antiplatelets
  • Platelet Transfusion

May Require:

  • IV immunoglobulin
  • Steroid
  • Anticoagulation with: DOAC, Fondaparinux, Argatroban

Further reading

 

Methaemoglobinaemia

Q: Why are Smurf’s Blue? 

A: Methaemoglobin (MetHb) of course!

MetHb is produced by oxidisation of the Iron in Haemoglobin (Hb) from Fe2+ to Fe3+

Fe3+ prevents Hb carrying oxygen (thus produces symptoms of hypoxia)

Often due to chemical ingestion, but may also be genetic

Treated with Methyl Blue & supportive measures

Read more

Primary Intracerebral Haemorrhage

In anybody who there is suspicion of a non-traumatic haemorrhage arrange an urgent CT Head.

All patients need IV access and  U&E, FBC, Coag

If CT confirms PICH (not traumatic, not SAH): –

Anticoagulation

If anticoagulated with warfarin or NOAC discuss with stroke consultant and Haematologist regarding reversal

If not anticoagulated give Tranexamic acid – 1g in 100mls Saline/Glucose over 10 mins followed by 1g in 250mls Saline over 6 hours.

Blood Pressure

BP needs to be <150/80 – use labetalol (max 400mg – until BP <160 or HR <50) and GTN infusion

Neurosurgical Referral

Not all patients with intracerebral bleeds need referral to neurosurgery – you could save yourself and your patient a lot of time and effort!

Those to refer:

  • GCS 9-12/15 with lobar haemorrhage
  • Isolated intraventricual haemorrhage
  • Hydrocephalus on presentation
  • Rapid deterioration following arrival (gcs drop by 2 points or more in the motor component)
  • Cerebellar bleed

Admit those not going to Neurosurgery to HASU at CRH after discussion with Stroke team

Trust Dalteparin dosing

Trust Guidance varies slightly from BNF for those patients over 100kg

Non-Pregnant PE/DVT treatment

Dalteparin Cr Clearance >29ml/minDalteparin Cr Clearance 20-29ml/min
Weight (kg)DoseWeight (kg)Dose
<45kg7,500 units OD<63kg5,000 units am
2,500 units pm
45-56kg10,000 units OD63-80kg5,000 units BD
57-68kg12,500 units OD81-98kg7,500 units am
5,000 units pm
69-82kg15,000 units OD99-116kg7,500 units BD
83-100kg18,000 units OD117-134kg10,000 units am
7,500 units pm
101-115kg10,000 units BD135-152kg10,000 units BD
116-140kg12,500 units BD
>140kg15,000 units BD

Pregnant PE/DVT treatment

Weight (kg)Dose
<50kg10,000 units OD
50-69kg12,500 units OD
70-79kg15,000 units OD
80-89kg18,000 units OD
90-109kg20,000 units OD
110-124kg22,500 units OD
125-139kg12,500 units BD
140-154kg15,000 units am
12,500 units pm
155-169kg15,000 units BD

Transfusion Care Pathway

PDF: Transfusion Care Pathway

When giving blood products you need to use the transfusion care pathway.

It can be found on intranet > Policies & Documents Library >Other Systems [green button] > Clinical records repository > Search [title And transfusion] – its only 9 clicks away (and some writing)