Labs Flashcards
Normal Hemoglobin Values
12-18 g/dL
Low Hemoglobin value
Anemia: hemoglobin <12g/dL
hgb <7g/dL requires blood transfusion
Anemia Signs and Symptoms
dizziness; lightheadedness; fall risk
Polycythemia
High Hemoglobin (>18g/dL)
Signs and Symptoms of Polycythemia
fatigue, weakness, shortness of breath, visual disturbances, nose bleeds, bleeding gums.
Hematocrit
Directly related to hemoglobin; the ratio of RBC to total blood volume
Normal is 37 - 57%
Normal RBC Count
4.5 - 5.5 million
Normal WBC Count
5,000 - 10,000
Leukopenia
Low WBC count (>5,000); immunocompromised
Causes: Cancer, immunosuppression, autoimmune disease, IV Abx.
Leukocytosis
High WBC count (>10,000); caused by infection and surgery
Normal Platelet Count
4.5 - 5.4 million
Thrombocythemia
high platelet count (>5.4 million); clot risk
Thrombocytopenia
low platelet count (<4.5 million); increased risk for bleeding.
Normal Sodium Level
135 - 145 mEql/L
Hyponatremia
<135 mEq/L
Euvolemic Hyponatremia
water in the body decreases, but the sodium level remains the same. Caused by SIADH, polydypsia, adrenal insufficiency, excessive hypotonic IV fluids, and low dietary sodium.
Signs and symptoms: weak pulse, tachycardia, hypotension, dizziness.
Treatment: water restriction, osmotic diuresis, and increased PO sodium.
Hypervolemic Hyponatremia
water in the body increases to the point of hypervolemia, which dilutes the amount of sodium in the serum, causing dilution or relative hyponatremia.
Causes: CHF, RF, liver failure, and water intoxication.
Signs and Symptoms: bounding pulse, hypertension.
Treatment: water restriction, increased osmotic diuresis, increased sodium intake.
Hypovolemic Hyponatremia
loss of sodium and water.
Causes: vomiting, diarrhea, diuretics (furosemide), burns, and excessive sweating.
Signs and Symptoms: seizure, confusion, lethargy, cerebral edema, increased ICP, cramps, weakness, shallow resps, muscle spasms, OH, loss of appetite, hyperactive bowel sounds.
Treatment: 0.9% NaCl; if severe, 3% NaCl
Foods High in Sodium
canned or processed foods, frozen foods, lunch meats, cheeses, bacon, table salt, etc.
Normal Potassium Levels
3.5 - 5.0 mEq/L
Hyperkalemia
high serum potassium; caused by too much potassium shifting out of cells such as with burns, tissue damage, DKA; or too much potassium as a result of renal failure and excessive potassium uptake; or with taking potassium sparing diuretics or ACE inhibitors.
Hypokalemia
low potassium (<3.5); caused by drugs such as laxatives, diuretics, or corticosteroids, too much water intake, or heavy fluid loss such as with NG suction, vomiting, diarrhea, wound drainage, sweating, alkalosis, and hypertension; inadequate potassium intake such as with NPO, anorexia, bulimia, alcoholism, Cushing’s syndrome, retention of sodium and water, excessive cortisol, or excessive secretion of potassium.
Hypokalemia Treatment
Treatment: hold digoxin; hold potassium-wasting drugs; give potassium, IV or PO (NEVER PUSH); give tomatoes, oranges, avocados, bananas, etc.
ECG Changes caused by Hypokalemia
ECG Changes: U-Wave appearance after peaked T-wave followed by abnormal T-wave.
Signs and Symptoms of Hypokalemia
Signs and Symptoms: decreased reflexes; weakness; faccidity; shallow respirations; decreased bowel sounds; constipation; abdominal distension; OH; weak pulses; cardiac dysrhythmias; and increased urinary output.
Hyperkalemia Treatment
Treatment: dependent on severity
- monitor cardiac ECG
- DC potassium supplements
- potassium-restricted diet
- IV calcium gluconate or chloride
- D5W with regular insulin to drive potassium back into cells
- albuterol, bicarbonate
- kayexalate to remove K+ from feces
- Diuretics such as hydrochlorothiazide or furosemide
- dialysis if unresponsive to treatment.
Signs and Symptoms of Hyperkalemia
Signs and Symptoms: muscle weakness, decreases reflexes, numbness, shallow respirations, cramping, hyperactive bowel sounds, diarrhea, impaired contractility, decreased CO, weak pulses, hypotension, urine abnormalities, and ECG changes (wide, flat p-waves with widened QRS, depressed ST, and tall, peaked T-waves.
Normal Chloride Levels
98 - 106 mEq/L
Hypochloremia
decreased chloride levels (<98mEq/L)
Causes: Fluid overload (CHF, water intoxication), salt loss (burns, sweating, vomiting, diarrhea, cystic fibrosis, acidosis, Addison’s disease).
Signs and Symptoms of Hypochloremia
seizure risk; weakness; fatigue; SOB; diarrhea/vomiting; signs of dehydration.
Treatment for Hypochoremia
monitor electrolytes; treat the cause with 0.9% NaCl
Osmolarity of urine
300 - 900 mOsm/Kg H20
Serum Osmolarity
285 - 295 mOsm/Kg H20
Urine Specific Gravity
the ratio of the density of a substance to the density of a standard, usually water.
Normal is 1.005 - 1.030
increased USG = dehydration
decreased USG = needs electrolytes
Normal Calcium Levels
9 - 10.5 mEq/L
Normal Magnesium Levels
1.5 - 2.5
Normal Phosphorus Levels
2.5 - 4.5
Normal Glucose Levels
70 - 110 g/dL
Normal BUN
10 - 20
Normal Creatinine
0.6 - 1.2
Normal GFR
> 90
Normal Total Protein
6.4 - 8.3
Normal Albumin Levels
3.5 - 5
Normal Bilirubin
<1
Normal Ammonia Levels
15 - 110
Normal Liver Enzymes
AST: 0 - 35
ALT: 4 - 36
ALP: 30 - 120
GFR indicating kidney damage
<30
GFR indicating kidney failure
<15
Considerations for CT
Computed tomography scans may be performed with or without contrast. This procedure uses radiation and is commonly indicated for abdominal pain, stroke, and spinal cord injuries.
If contrast is administered, a baseline creatinine and eGFR should be obtained. The client should be instructed to increase their fluid intake following a contrast procedure to facilitate its passing.
Before IV contrast administration, prescreening must include questioning the patient regarding prior reactions to contrast dye or allergies to medications/substances. Any allergy (not specifically shellfish) may increase the risk of having an IV contrast dye reaction.
If there is a history of severe allergies or prior reaction to contrast dye, such patients may be premedicated with diphenhydramine and steroids.
Shellfish allergy is not a contraindication.
Patent vascular access of at least a 20-gauge catheter is necessary before the infusion of intravenous contrast. Extravasation of contrast media can be severe, and treatment involves stopping the infusion, removing the catheter, and elevating the extremity above the heart. This can be avoided by establishing IV patency before the infusion of contrast. Warm or cold compresses may also be helpful.
CT
uses many x-rays to generate 3D anatomical images
donut shaped scanner
may or may not use contrast
each set of scans takes 5-10 mins
best way to see detail of bony structures
check renal function first
If contrast is used, increase PO fluid intake, monitor output, hold meftormin for 24 hrs and up to 48 hrs after to avoid risk of lactic acidosis
MRI Considerations
Nitroglycerin transdermal patches should be temporarily removed during the procedure because they may burn the client. The transdermal patch may contain aluminum which is contraindicated for an MRI.
An MRI questionnaire is always completed before this exam to ensure client safety. MRI units can produce sounds up to 120 decibels, resulting in hearing damage. MRIs do not use radiation; this imaging exam uses magnets to create 3D cross-sectional images of the body.
Uses magnetic fields & radio waves to
generate 3D anatomical images (no radiation)
* Lasts 15 - 60 minutes
* May show soft tissue/organ changes
* Great for brain, spinal cord, & nerves
* May or may not use contrast
* Ensure client has no metal obiects in/on them
* Assess for claustrophobia * Check if client has pacemaker (old machines
may deactivate pacemakers) * Contraindications: agitation, old tattoos
An MRI is a unique imaging exam that uses magnets (not radiation) to assist clinicians in diagnostic imaging. MRI is most suited to image soft tissue structures in the body with a high water content to utilize the protons in water molecules. The brain and spinal cord are often evaluated using MRI. MRI can differentiate between gray and white matter and blood vessels.
Nursing care for a client scheduled for an MRI includes -
Completing a comprehensive MRI screening form that is submitted before the exam.
MRIs are safe during pregnancy because it does not use radiation.
MRIs may be ordered with contrast. The contrast agent of choice is gadolinium-based.
The MRI may become unsafe for a pregnant client if this contrast is necessary.
MRI safety includes having the client wear ear protective device(s) as this test is extremely loud.
Which labs would be expected after a client receives an angiogram with contrast?
In order to yield valuable, quality results from an angiogram, the use of contrast media is essential. Like all medications and substances, risks are present even when utilizing the minimum amount required. Two documented risks of contrast media are contrast-associated acute kidney injury (CA-AKI) and contrast-induced nephropathy (CIN), as contrast media is metabolized in the kidneys. To assess for kidney damage, kidney function tests are performed one day after the client receives contrast media to evaluate renal function and compare the result to the pre-procedure testing result.
Adequate hydration before and after contrast agent administration is regarded as the most important preventive strategy for circumventing kidney injuries.
