N.couse case study_hit

Heparin Induced

Thrombocytopenia

By: Niccole Couse

University of South Florida

College of Nursing

IntroductionBaroletti & Goldhaber, 2006

• Heparin Induced Thrombocytopenia is a complication of Heparin therapy that leads to decreased levels of platelets in the blood.

• Two types– Immune mediated

• DANGEROUS

• Rare

– Non-Immune mediated• Self limited

• Common

Heparin Mechanism of Action

• Most common anti-coagulant used in the hospital setting. (Cooney, 2006)

• Does not normally affect platelets directly (Baroletti &

Goldhaber, 2006)

• Binds with anti-thrombin to increase it’s efficacy of inhibiting

– Thrombin

– Platelet factor Xa

– Platelet factor IXa

– Platelet factor XIIa(Krishnaswamy, Lincoff & Cannon, 2010)

Normal Heparin Side Effects(Deglin, Vallerand & Sanoski, 2012)

• Signs/symptoms of bleeding– Bruising or blackening

• Around injection site

• On fingers, toes and nipples

– Bleeding gums

– Nose bleeds

– Hematuria

– Melena

– Hypotension

– Decreased H&H

HIT PathophysiologyCooney, 2006

Immune mediated

• Generally presents within 5–14 days of heparin administration

• Drop of platelet count by 30-50%

• Requires treatment – can be fatal

• Immune response to heparin and platelet factor IX complex

– Often leading to thrombosis

Non-Immune mediated

• Presents within 5 days of

heparin administration

• Minimal drop in platelet

count

• Will generally resolve on

own

– Continued exposure debated

• Does not result in bleeding

or thrombosis

Incidence Cooney, 2006

• Heparin widely used in hospitalized patients

– 1/3 or about 12 million annually

• % of patients that will develop HIT

– Non-Immune mediated ~ 10%

– Immune mediated ~ 5%

Risk FactorsCooney, 2006

• Unfractionated Heparin use

– LMW heparin is safer

• IV heparin use

– Sub Q is safer

• Orthopedic, cardiovascular & trauma patients

– Cardiovascular patients– more at risk for arterial thrombi

– Orthopedic & trauma patients – more at risk for venous thrombi

ComplicationsCooney, 2006

• HITTS – heparin induced thrombocytopenia

thrombotic state

– Complication of Immune mediated HIT

– Formation of IgG antibody to heparin+PF4

complex >

• Activates platelets releasing pro-coagulant rich micro-

particles

• Lyses platelets

HITTSCooney, 2006

• Dangerous complication of Immune mediated HIT– 38-76%

• Characterized by excessive clotting in the blood.

• Clots can travel throughout the body causing harm.– DVT 50%

– PE 25%

– Limb necrosis 20%

– Death

– Other target organ damage• Stroke, MI, ARF, etc.

Diagnosis(Baroletti & Goldhaber, 2006)

• Drop in platelet count after initiation of Heparin therapy (30-50%)

– Presence of HIT

• Presence of Heparin + PF IX complex antibody in blood

– What type of HIT would this indicate?

• Symptoms of clot formation

– What complication does this indicate?

Signs and Symptoms(Baroletti & Goldhaber, 2006)

• HIT

– Drop in platelet count 30-50%

• HITTS

– Drop in platelet count 30-50% +

– Symptoms of DVT• Pain & tenderness of the legs

• Sudden swelling

• Warm skin

• Discoloration of the skin

– Symptoms of PE• SOB

• Chest pain

• Anxiety

• Dizziness

• Alterations in HR

– Symptoms of other target organ damage

Assessment

• Be aware!

• Closely monitor patients on Heparin therapy

– Monitor platelet count

• Normal?

– Monitor PTT, PT, INR

– Monitor for S/S of bleeding and clotting

Treatment(Cooney, 2006)

• STOP HEPARIN!!

• Begin other approved anticoagulant

– Direct thrombin inhibitors

• Argatroban & Lepirudin

• Block activation of thrombin and do not trigger antibody-mediated reactions

• Symptom management

• Warfarin can be started after treatment and platelet count reaches minimum of 100,000

Treatments – nursing considerations

• Monitor daily INR

• Reduce thrombosis– Anti-embolism stockings

– Increase activity/exercise • Ambulation

– Hydration

• Careful observation

Prognosis

• Highest mortality rate in Immune-mediated

HIT

• 6-10% mortality (Ecke & May, 2012)

– DVT 50%

– PE 25%

– Limb necrosis 20%

– Death (Cooney, 2006)

Nursing Diagnosis

• Risk for

– Ineffective tissue perfusion

– Ineffective gas exchange

– Decreased cardiac output

– Acute renal failure

– Altered mental status

– Etc.

Clinical Example

• HPI: Patient 73 year old male admitted to the

hospital with a C.C. of shortness of breath.

Diagnosed with new onset A.fib and received

cardioversion to sync back to NSR. Pateint

received a TEE revealing severe mitral valve

calcification and regurgitation. He was

scheduled for a cath but elected to go home

until the surgery due to breathing much better.

Clinical Example

• Patient came back early due to SOB and

remained hospitalized until the surgery. He

received a CAGB X1 and MV replacement. He

received Heparin during the surgery. (1st use)

Clinical Example

Complications –

• 6 days post op he began experiencing increasing SOB – received a CT that identified small bilateral PEs. Also became acutely confused

• His platelet level dropped to 94,000

• In the following days he began exhibiting signs of

– Acute renal failure (elevated BUN and Creatnine and anuria)

– Poor tissue perfusion (R foot: molten toes, cool skin and diminished pulses)

– Liver damage (liver function tests diminished)

Relating to the Patient

• Pulmonary embolisms

• Acute confusion

• Arterial embolism in the R leg?

• ARF requiring dialysis

• Liver function decline

NCLEX style question

• TRUE or FALSE?

–All patients that develop HIT will

experience thrombosis?

NCLEX style question

• TRUE or FALSE?

–All patients that develop HIT will

experience thrombosis?

FALSE

NCLEX style question

• A patient is started on a Heparin subQ

injections daily. You begin to notice bruising

around the injection site. You attribute this

finding to ….

a) HITTS

b) Expected side effect of Heparin therapy

c) Possible physical abuse

d) Allergy to alcohol wipes

NCLEX style question

• A patient is started on a Heparin subQ

injections daily. You begin to notice bruising

around the injection site. You attribute this

finding to ….

a) HITTS

b) Expected side effect of Heparin therapy

c) Possible physical abuse

d) Allergy to alcohol wipes

Questions?

References

• Baroletti, S.A. & Goldhaber, S.Z. (2006) Heparin induced

thrombocytopenis. Journal of the American Heart

Association.

DOI:10.1161/CIRCULATIONAHA.106.632653

• Cooney, M.F. (2006) Heparin induced thrombocytopenia:

Advances in diagnosis and treatment. Critical Care Nurse,

26(6). Retrieved from

http://ccn.aacnjournals.org/content/26/6/30.full.pdf+html

References

• Deglin, Vallerand & Sanoski (2012) Davis drug guide

• Ecke, S. & May, S.K. (2012) Geparin induced thrombocytopenia follow-up. Retrieved from

http://emedicine.medscape.com/article/1357846-followup#a2650

• Krishnaswamy, A. Lincoff, M., & Cannon, C.P. (2010) The use and limitations of unfractioned heparin. Critical Pathways in Cardiology 9(1) Retrieved from

http://www.automedicsrx.com/publications/The_Use_and_Limitations_of_Unfractionated_Heparin.pdf