4. Potassium (K)
Normal
3.5 – 5.5 mEq/L
• Hyperkalemia: dehydration, trauma
(hemolysis), acidosis, renal disease, use of K
sparing diuretics. Membrane potential will
become closer to threshold can lead to
fibrillation and cardiac stand still
• Hypokalemia: Vomitting/diarrhea, diuretics,
excessive sweating, cellular shifts.
• Zebra: Cushing’s disease. Less excitable
membranes can lead to bradycardia.
6. Bicarbonate:
Normal
23 – 32 mEq/L
• Why this is valuable: information as to
overall perfusion and saturation of RBC.
Significant alteration in either positive or
negative directions is not desirable and may
indicate the presence of an anemia or
significant blood loss recently.
7. BUN (Blood Urea
Nitrogen):
Normal
10 – 20%
• BUN is a produced by protein breakdown in
liver and excretion by the kidney.
• Elevated BUN (azotemia) indicates possible
crush injury, infection, excessive protein
intake or an inability of kidneys to excrete
BUN (renal dz, hypotension).
• Decreases: liver is unable to breakdown
protein or malnutrition.
Not as reliable as creatinine because BUN is
dependent on age, gender, lean body mass
and etc.
8. Creatinine (Cr):
Normal
0.7 – 1.4
• Byproduct of creatine produced by the liver
and kidneys and is used as an energy
storehouse in skeletal muscle. Creatinine is
completely filtered by the kidneys and is not
reabsorbed or secreted, thus its an excellent
measure of GFR (glomerular filtration rate).
• Elevated serum creatinine is most specific
for renal dz, creatinine clearance, usually
greater than 80 ml/min is the best way to
assess renal function. It requires a 24 hr
urine specimen, but it can be estimated
using the equation:
• [(140 – age) x wt (kg) (0.85 for women)] / 72
x creatinine clearance
9. Glucose: Normal
80 – 120 mg/dl
• Most offen used in diagnosing and managing
diabetes. Diabetes can be diagnosed as a
fasting blood sugar >126 mg/dl and 2 hour
post prandial blood sugar over 200 mg/dl.
Glucose can also be elevated by
hyperthyroidism or from thiazide diuretics
Glucose can be decreased in pancreatic
neoplasms and Addison’s disease
10. Hemoglobin
A1C
Normal:
3 – 6%
• Can be 3 – 6% in non diabetics. In
uncontrolled diabetics it can be as high as
10% (or higher).
• Good estimate for judging a patient’s long
term control
17. Basophils:
Normal 1 – 2%
• Source of histamine; contain heparin
• Increase in basophils is usually associated with
an increase in Mast cells (basophils in tissue)
• Increase: myxedema, blood vessel injury
22. Microcytic Anemias
(Fe deficiency anemias)
D/Dx pneumonic = TICS
T – Thalassemias
I – Iron Deficiency
C – Chronic Inflammation (anemia)
S – Sideroblastic anemia (check pt for Pb toxicity)
23. Normocytic Anemias
D/Dx pneumonic = NORMAL S(I)ZE
N - Normal pregnancy (volume expands up to 30% plasma vol)
O - Over hydration
R - Renal (chronic renal disease => lower EPO production)
M – Myelophistic: replacement of bone marrow w/ tumor
A – Acute blood loss
L – Liver disease
S – Systemic Inflammation
Z – Zero production
E – Endocrine disorders e.g. hypothyroid disease
24. Macrocytic Anemias
D/Dx pneumonic = BIG FAT RED CELLS
B – B12 deficiency
I – Inherited problem
G – G/I
F – Folic Acid deficiency
A – Alcoholism
T – Thymine responsive
R – Reticulocytes (larger than mature RBC),
therefore inflate MCV
E – Endocrine
D – Dietary problems (lack of dietary folate, B12
etc.)
C – Chemotherapeutic Rx
E – Erythroleukemia
L – Liver Disease
L – Lesch- Nyan Syndrome (“zebra”)
S – Splenectomy
25. Hemolytic Anemias
(Increased rate in destruction of RBC)
D/Dx pneumonic = HEMATOLOG(I)ST
H – Hemoglobinopathy (most common is sickle cell)
E – Enzyme deficiency
M – Medication (drug induced)
A – Ab
T – Trauma to RBC
O – Ovalocytosis (Autosomal Dom disorder in pop w/ south east asia)
L – Liver Disease
O – Osmotic Fragility
G – Glucose 6-P DH Deficiency
S – Splenic destruction
T – Transfusion related
27. Bleeding Time: Normal 2 – 9 minutes
• Normal time is via a controlled forearm scratch.
• Increase: ASA and NSAIDs
Platelet Count: Normal 150,000 – 450,000
• Indication of cessation of bleeding following an operation.
• Below 25,000 may indicate spontaneous bleeding
28. PT: Normal 11 – 16 sec
Measures the extrinsic coagulation pathway
Normal in Hemophilia A & B
Increase in Vitamin K, impaired fat absorption, liver dz, warfarin
(coumadin)
PTT: Normal 25 – 35 sec
Measures the intrinsic coagulation pathway
Normal in thrombocytopenia, platelet dysfunction, von Willebrand’s dz
Increased: Hemophilia A & B, prothrombin complex disorders, heparin
29. Radiographic Analysis
- Always obtained for any patient undergoing osseous resection, penetrating wounds,
ulcerations
- Several standard views (usually 3)
- Good quality
-Available at time of surgery
Cultures
- Any open wound, especially in diabetic or immunocompromised patients
- Will help with individual tailoring of abx treatment
Ancillary Tests
- Women under the age of 50 – pregnancy or HCG test should be performed
- Patients over the age of 40 – EKG to rule out arrhythmias
- Over 50 with history of smoking – Chest X-ray
