inpatient / hematology and oncology
Anemia
# Anemia
Assessment:
-- History: *** EtoH use, prev bleeds (menstruation, GI), autoimmune dx, nutritional status, vegetarian/vegan, recent meds, bariatric surgery
-- Clinical: *** fatigue, lightheadedness, SOB/DOE, angina, melena, Pica, restless legs
-- Exam: *** pallor, jaundice, glossitis, motor/sens deficits, splenomegaly, brittle nails, hair loss
-- Data: *** MCV, RDW, retic abs and %, smear, iron studies, B12/folate, TSH, bilirubin, LDH, haptoglobin, DAT, coags, UA
-- Etiology/DDx: *** Underproduction (IDA, Chronic Inflammation, ESRD, Folate/B12, Alcohol, Marrow Suppression) vs Destruction/Loss (GI malignancy, Menorrhagia, MAHA, immune-mediated) vs Genetic/Intrinsic (mostly zebras); Anemia AND Thrombocytopenia: Hypersplenism, EtOH, babesiosis, Evans syndrome, B12 deficiency, TMAs (e.g. TTP), HLH, PNH
The patient's HPI is notable for ***. Exam showed ***. Labwork and data were notable for ***. Taken together, the patient's presentation is most concerning for ***, with a differential including ***.
Plan:
Workup
-- Initial Labs - CBC w/ diff (MCV, RDW), Retic abs count and %, smear
-- Calculate Retic Index (RI) - if <2%, hypoproliferation/underproduction
-- Anemia Labs - iron studies, folate/B12, BMP, LFTs, TSH, CRP; SPEP, EPO, BMBx
-- Hemolysis Labs - LDH, bilirubin, haptoglobin, DAT (Coombs), coags, UA
-- Consider EGD/Colo if c/f GIB
Treatment
-- Transfuse Hgb <7
-- IDA - tablets 325mg iron sulfate QOD vs IV iron sucrose 300mg QOD x3
-- ESRD - EPO
-- Folate/B12 - replete
PDF coming soon!
If You Remember Nothing Else
Many patients will be anemic in the inpatient setting. Determine if the process is acute and life-threatening, or represents a chronic process, and be mindful of iatrogenic causes. In general, transfuse Hgb >7, but be judicious since blood products are a scarce resource and, like all treatments, have their own risks.
Clinical Pearls
- Approximately two-thirds of critical patients admitted to an ICU have a hemoglobin concentration of less than 12 g/dl on the day of admission, and 97% of the patients become anemic after a week in ICU
- Inpatient etiologies of anemia include phlebotomy, GI bleed, marrow suppression due to inflammatory cytokines, decreased EPO from renal dysfucntion, nutritional deficiency, and increased hemoylsis due to toxins and drugs
- Most evidence suggests a restrictive transfusion strategy >7 g/dl instead of a liberal goal of >10; a notable exception is in those with a history of heart disease in which a goal of >8 may confer benefits
- The average ICU patient has ~40-70ml of blood drawn daily, which equals 1 unit of blood per week
- GI Bleeding from stress (occult or visible) is common in intubated patients and those with coagulopathies (reason we give PPI)
- Cytokines decrease EPO release and marrow production, and lead to iron sequestration in macrophages and increased destruction of RBCs by macrophages
- Penicillins and Cephalosporins are commonly used drugs that can cause hemolysis
- Giving iron to patients with infection is controversial based on an association with the growth and virulence of microbes and the theory that the body decreases iron as a defense in the setting of sepsis
Trials and Literature
- Prevalence and Causes of Anemia in Hospitalized Patients (J Clin Med, 2020)
- Anemia is Intensive Care: A Review of Current Concepts (J Crit Care Med, 2016)
- Indications For and Adverse Effects of Red-Cell Transfusion (NEJM, 2017)
- FAIR-HF Trial - IV iron (ferric carboxymaltose) regardless of anemia in patients with HF; Rationale - many HF patients have fatigue, dyspnea, and poor QOL; 459 patients (75 sites in 11 countries) Class II or III, EF<40%, iron deficiency - 2:1 iron vs. placebo; Endpoints: self-reported patient global assessment at 24 weeks; distance walked in 6 minutes, health-related quality of life; 50% much or moderately improved vs. 28% placebo; 47% decreased NYHA class vs 30% placebo; improved 6-minute walk, QOL; Similar rates of death, hospitalization, AEs; Issues - almost 100% white, more of treatment arm was getting AC (NEJM, 2009)
Other Resources
