HEMATOLOGY/ONCOLOGY

 

Anemia

Check peripheral smear & retic count, ferritin & iron studies (transferring, %sat, TIBC, Fe)

High retic count –

Hemolysis due to G-6PD, Sickle cell, Autoimmune, drug-induced, microangiopathic (DIC,  HUS, TTP, prosthetic valve, etc), PNH, hereditary spherocytosis, or malaria. 

Dx: LDH, haptoglobin, direct bili, direct coombs

Low retic count –

Microcytic: 

(1) Fe deficiency -- Dx: ferritin <30 is 98% specific for Fe def; also low %sat & serum Fe with high transferrin & TIBC. Consider colonoscopy to r/o occult colon ca. 

(2) Anemia of Chronic dz -- Dx: low % sat, TIBC, high ferritin.

(3) Thalassemia --  Dx: nl iron studies, very low MCV

 

Normocytic: anemia of chronic dz (esp. liver, renal, thyroid), blood loss, pure red cell aplasia (check parvovirus B19), drug rxn. Dx: Consider bone marrow bx for sideroblastic or myelodysplastic syndromes.

 

Macrocytic:  folate deficiency, B-12 deficiency/pernicious anemia, AZT or other drugs                         

Dx: B-12, RBC folate levels or MMA (high with B12 deficiency) / homocysteine (high with B12 or folate deficiency).

 

Blood Product Transfusion Risk & Reactions

Noninfectious complications of blood transfusions:

Febrile 1:100

Allergic 1:100

Delayed hemolytic reaction 1:1,000

Acute hemolytic reaction <1:250,000

Fatal hemolytic reaction <1:100,000

Transfusion related acute lung injury 1:5,000

 Infectious complications of blood transfusions:

CMV: common

Hepatitis B: 1:63,000

Hepatitis C 1:103,000

HTLV <1:100,000

HIV 1:493,000

 

If transfusion reaction occurs – stop transfusion, send remaining blood product to blood bank for anaylsis, treat with Tylenol (if fever) +/- Demerol 25mg iv x 1, can reapeat in 1hr (if rigors) or Diphenhydramine (if rash, pruritis),  H2 blocker/Prednisone/Epinephrine (if urticaria, bronchospasm, laryngeal edema, hypotension), and IVF.

 

Heparin Protocol

One of multiple dosing algorithms is as follows:

Bolus (only for acute indications & minimal bleeding risk) 5000 units.  Then continuous 1200 units/hr.  Check aPTT in 6hrs.  Goal ratio: 1.5 – 2.5. 

 aPTT (ratio)            rebolus        hold      infusion                         next APTT

< 35s (<1.2)             80 u/kg      --          increase 4u/kg/hr           6hr

35-45 (1.2-1.5)          40 u/kg      --          increase 2u/kg/hr           6hr

46-70 (1.5-2.3)             --                        --          --                                  next AM

71-90 (2.3-3.0)             --                        --          decrease 2u/kg/hr          next AM

>90   (>3.0)                 --                        1hr        decrease 3u/kg/hr          6hr

NOTE: if aPTT is abnormally high double check that blood draw was not downstream from heparin infusion. [Tarascon Internal Medicine & Critical Care Pocketbook, 2nd Ed]

 

Hypercoagulabiliy

Virchow’s Triad: changes in vessel wall, blood flow, &/or blood composition

Risks: age, immobility, major surgery, malignancy, oral contraceptives, HRT, APLS, essential thrombocythemia, polycytemia vera, PNH, ATIII deficiency, Prot C/S deficiency, Factor V Leiden, Prothrombin 20210A, dysfibrinogenemia, hyperhomocysteinemia, increased factor VIII, IX, XI, APC-resistance, high levels of thrombin activatable fibrinolysis inhibitor.

Studies: (note: many studies are unreliable in the setting of acute thrombosis &/or anti-coagulation) consider APC, Russel viper venom, anti-cardiolipin, Prot C/S, Factor V Leiden, Prothrombin 20210A  [Hematology (2002) 353- 58]

Sickle Cell Vaso-Occlusive Criseis –vaso-occlusive crisis (VOC)

Dx: hct, reticulocyte count, CXR, consider blood cultures, if low reticulocytes: parvovirus B19 pcr

Triggers: cold, stress, dehydration, infection, ischemic event, drugs

Rx: PCA, IVF (200 – 250cc/hr), O2 via NC, incentive spirometry (q2hr while awake), NSAIDS (ibuprofen 800mg q8h), folic acid 1mg po qd, keep room warm, check daily hct and reticulocyte count

Acute chest crisis (new multilobar infiltrates + CP, fever, tachypnea, wheezing, or cough) occurs on average of 2.5d after admit for VOC & is potentially fatal.  Manage with abx (gatifloxacin), O2, transfusion (exchange or simple)

 [NEJM (1995) 333:699 – 703. NEJM (1999) 340: 1021 – 30.  NEJM (2000) 342: 1855 – 65.]

 

Hypercoagulability

Virchow’s Triad: changes in vessel wall, blood flow, &/or blood composition

Risks: age, immobility, major surgery, malignancy, oral contraceptives, HRT, APLS, essential thrombocythemia, polycytemia vera, PNH, ATIII deficiency, Prot C/S deficiency, Factor V Leiden, Prothrombin 20210A, dysfibrinogenemia, hyperhomocysteinemia, increased factor VIII, IX, XI, APC-resistance, high levels of thrombin activatable fibrinolysis inhibitor.

Dx: note: many studies are unreliable in the setting of acute thrombosis &/or anti-coagulation consider APC, Russel viper venom, anti-cardiolipin, Prot C/S, Factor V Leiden, Prothrombin 20210A  [Hematology (2002) 353- 58]

 

Neutropenic Fever

Refer to Hopkins Antibiotic Guidelines (yellow book) for treatment algorithm