Lab Values Flashcards
What are lab results for?
Screening
Diagnosis
Monitoring
Factors affecting lab values
Age
Gender
Race
Pregnancy
Food ingestion
Urine studies are used to
Detect/diagnose and monitor renal and urinary disease
Detect metabolic/systemic disease
Urine reflects ________ __________ of a substance if kidney function normal
Blood levels
Desired result of urinalysis
Clear, yellow-amber color
No ketones, WBCs, or protein
24 hour urine is for
Hormones, protein, creatinine
When doing a 24 hour urine test, what do you do before?
Ask pt to void, and discard the first voiding.
All urine is saved in a container for 24 hr, and must be kept
Cool
24 hour urine sources of error:
Contaminants in the urine
Failure to collect all urine in time period
Including 1st voided urine
Improper storage/preservation of specimen
CrCl
Creatinine clearance
CrCl can detect and diagnose
Kidney dysfunction and/or decreased blood flow to kidneys
CrCl test requires
24 hr urine test and 1 blood specimen
Osmolality of urine measures
Dissolved particles in urine
Osmolality of urine determines
Kidneys concentrating ability
Fluid & electrolyte abnormalities
Normal serum osmolality
280-300 mOsm/L
HCT
Hematocrit
HCT values assess
Hydration status, anemia, oxygen transport
Buffy coat
White blood cells, platelets
High levels of HCT
Dehydration, diuretics, burns
High altitude, hypoxemia, COPD
Low levels of HCT
Levels tend to decrease with age
s/s of anemias, blood loss, over hydration
Extremely elevated WBCs
High levels of serum osmolality
Dehydration
Increased Na or glucose
HHNK or DKA
Diuretic therapy
Low levels of serum osmolality
Over hydration
SIADH
CA- breast, colon, lung
PreAlbmin is used to monitor
Nutrition status and effects of treatment
Liver function
Increased PreAlbumin
Hodgkins disease, pregnancy
Decreased PreAlbumin
Malnutrition, liver disease, inflammation
Culture and sensitivity
Urine, blood, wound drainage, tissue and devices
Culture for fungus may take up to
6 weeks
Gram positive
Blue staining organism
Gram negative
Red staining organism
Gram stain results take
10 mins
Therapeutic drug monitoring determines
Effective dose and prevents toxicity
Peak
Drug highest level in blood but below toxic level
Trough
Drug lowest level in blood but in therapeutic range
PT/INR
Monitoring or warfarin
Evaluation for vitamin K deficiency or severe malnutrition
Assessment of liver failure
PTT
Monitoring (but not initiation) of heparin
Assessment of clotting factor function in hemophilia and von Willebrand disease
Both PT/INR and PTT
Active bleeding without obvious cause
History of abnormal, excessive, or spontaneous bleeding
High risk patients
Production occurs in the
Bone marrow
Granulocytes
Basophils, eosinophils and neutrophils
CBC
Complete blood count
CBC is used to diagnose
Anemias
Bleeding disorders
Infections
Blood cell changes
CBC elements
WBC
RBC
HCT
HGB
Platelet count
WBC assessment of
Infection
Neoplasm
Allergy
Immunosuppression
WBC’s > 10,000 =
Leukocytosis
(Anemias, viral infections, ETOH, RA, trauma, physical or emotional stress)
WBC’s < 4,000 =
Leukopenia
(Acute infection, MI, cirrhosis, burns, dietary deficiencies)
Polymorphonuclear
Having a lobed nucleus
Commonly referred to as “polys”
Neutrophils
Phagocytosis
Bacterial infection, trauma
Eosinophils
Allergic reactions
Parasitic conditions
Basophils
Mast cells
Increase during healing process
Lymphocytes
Increase during chronic bacterial and viral infections
B lymphocytes
T lymphocytes
RBC
Red blood cells
Red blood cells are formed in
Bone marrow
Red blood cells:
Erythrocytes
Transport oxygen
Assess for anemias
High RBC levels =
Erythrocytosis
(Severe dehydration, COPD, polycythemia vera )
Low RBC levels =
Erythropenia
(Anemia, hemorrhage, bone marrow failure, cirrhosis, renal disease, lymphoma, leukemia)
Tourniquet on for >1min =
Hemolysis
HGB is highest in the
Morning
HGB is lowest around
Bedtime
HGB high levels
Dehydration, CHF, lung disease, heavy smokers
HGB low levels
Anemias, hemorrhage, hodgkins, kidney disease
MCV
Mean corpuscular volume
Average size of erythrocytes
HCT / RBC =MCV
MCH
Mean corpuscular hemoglobin
Average weight of erythrocytes
HGB / RBC = MCH
MCHC
Mean corpuscular hemoglobin concentration
Concentration of hemoglobin in 100 ml PRBC
HGB /HCT = MCHC
Platelets promote
Coagulation, vascular integrity
Platelets are produced in the
Bone marrow
Platelets are
Thrombocytes
Increased platelet levels =
Thrombocytosis (>400,000)
Thrombocythemia
> 1 million platelets
low levels of platelets
Thrombocytopenia (<100,000)
Normal urine osmolality
300-900 mOsm/L
Serum osmolality rough estimate
Na level x 2