Lab and Diagnositics Recorded Lecture NURN 155 Exam 2

What are the normal sodium and potassium ranges?

Sodium (Na+): 136–145 mEq/L. Potassium (K+, serum): 3.5–5.2 mEq/L.

What are the normal ionized and total calcium ranges?

Ionized Ca++: 4.65–5.28 mg/dL. Total serum calcium: 8.8–10.4 mg/dL.

What are the normal chloride, magnesium, and phosphorus ranges?

Chloride: 96–106 mEq/L. Magnesium: 1.8–2.6 mg/dL (may be slightly lower in 2nd/3rd trimester). Phosphorus: 2.7–4.5 mg/dL.

What are the BUN ranges for adults and older adults?

Adults: 6–20 mg/dL. Adults over 60: 8–23 mg/dL. BUN is used to evaluate kidney function and aid assessment of renal or liver disease.

What are the normal serum creatinine ranges by sex?

Males: 0.6–1.3 mg/dL. Females: 0.6–1.1 mg/dL. Creatinine helps estimate kidney filtration and is more sensitive to renal damage than BUN.

What are the normal AST and ALT ranges for males?

AST: 14–20 units/L. ALT: 10–40 units/L. They are included with liver-associated tests in the CMP.

What are the normal AST and ALT ranges for females?

AST: 10–36 units/L. ALT: 7–35 units/L. They are included with liver-associated tests in the CMP.

What are the normal albumin and prealbumin ranges?

Albumin: 3.5–5.2 g/dL. Prealbumin: 19–38 mg/dL. The lecture lists albumin among CMP tests; it does not explain prealbumin.

What are normal serum CO2, anion gap, and osmolality?

Serum CO2: 23–30 mEq/L. Anion gap: 8–16 mEq/L. Serum osmolality: 275–295 mOsm/kg H2O.

What are normal fasting glucose and HbA1c values?

Fasting glucose: ≤100 mg/dL (≤5.6 mmol/L). Hemoglobin A1c: ≤5.6%. HbA1c measures the percentage of hemoglobin coated with glucose.

What are the normal arterial pH, PaCO2, and HCO3− ranges?

pH: 7.35–7.45. PaCO2: 35–45 mm Hg. HCO3−: 22–32 mEq/L.

What are the normal PaO2 and SaO2 values?

PaO2: >80 mm Hg. SaO2: >94%. ABGs assess oxygen delivery to blood and elimination of carbon dioxide.

What is normal WBC count, and what are normal RBC counts by sex?

WBC: 4.5–10.5 ×10³ cells/mm³ (or ×10⁹/L). RBC males: 4.2–5.4 ×10⁶/mm³; females: 3.6–5.0 ×10⁶/mm³.

What are normal hemoglobin and hematocrit values by sex?

Hgb males: 14–17.4 g/dL; females: 12–16 g/dL. Hct males: 42–52%; females: 36–48%.

What is the normal platelet count?

140,000–400,000/mm³. Platelets support blood clotting and vascular integrity.

What are normal PT and aPTT values?

PT: 11–13 seconds. aPTT: 21–35 seconds. Both measure how long blood takes to clot.

What INR values must you know?

Not taking an anticoagulant: 0.8–1.2. Taking warfarin: 2.0–3.0. Mechanical prosthetic heart valve: 2.5–3.5.

What are normal total cholesterol, triglyceride, HDL ranges?

Total cholesterol: 140–199 mg/dL. Triglycerides: <150 mg/dL. HDL males: 35–65 mg/dL; females: 35–80 mg/dL.

What are normal LDL-C and LDL-P levels?

LDL-C: <100 mg/dL. LDL-P: <1,000 nmol/L. These are on your required lab list; the lecture does not explain LDL-P.

What are the normal T3 ranges for adults and pregnancy?

Adults: 80–200 ng/dL. Pregnancy: 116–247 ng/dL (1.8–3.8 nmol/L). Thyroid interpretation is not covered in the recorded lab lecture.

What are the normal T4 and TSH ranges?

T4: 5.4–11.5 μg/dL. TSH: 0.45–4.5 μU/mL (0.45–4.5 mU/L). Values preserved from your required list.

[Lab interpretation] Which symptoms distinguish low from high potassium?

Low K+: weakness, decreased reflexes, weak/irregular pulse, ECG changes. High K+: weakness, bradycardia, ECG changes, possible sudden cardiac arrest.

[Lab interpretation] How do low and high sodium differ in the lecture?

Low Na+: headache, weakness, tremors/seizures; can follow sweating, diuretics, vomiting/diarrhea. High Na+: thirst, restlessness, dry sticky mucosa, oliguria; often water loss.

[Lab interpretation] What are the major assessment cues for low versus high calcium?

Low Ca: facial/hand tingling, muscle twitching, Chvostek/Trousseau signs, tetany or seizures. High Ca: bone pain, kidney stones/flank pain, weakness, dehydration, stupor.

[Lab interpretation] What can cause low versus high chloride?

Low Cl: prolonged vomiting or gastric suction; sometimes low Na/K. High Cl: severe dehydration, renal shutdown, or excessive IV saline.

[Lab interpretation] Which conditions are linked to low and high magnesium?

Low Mg: chronic alcoholism, diarrhea, malnutrition, chronic kidney disease. High Mg: acute kidney injury or dehydration, per the lecture.

[Lab interpretation] What does the lecture emphasize about phosphorus and calcium?

Low phosphorus: malnutrition/malabsorption or excess diuretics. High phosphorus: renal failure or some skeletal conditions. Calcium and phosphorus often vary inversely.

[Lab interpretation] What is the difference between BUN and creatinine for kidney assessment?

BUN helps evaluate kidney function and renal/liver disease. Creatinine estimates kidney filtration and is more sensitive to renal damage than BUN.

[Lab interpretation] What does fasting glucose show versus HbA1c?

Fasting glucose checks the blood glucose at that time. HbA1c measures the proportion of hemoglobin coated with glucose; both help evaluate abnormal glucose control.

[Lab interpretation] How should a nurse interpret leukocytosis versus leukopenia?

Leukocytosis = high WBC; may suggest infection, inflammation, or tissue necrosis. Leukopenia = low WBC; may occur with viral illness, bone marrow suppression, or chemotherapy.

[Lab interpretation] What do the five white blood cell types do?

Neutrophils: primary defense. Eosinophils: parasites/allergy. Basophils: histamine/inflammation. Lymphocytes: B/T-cell immunity. Monocytes: clear debris.

[Lab interpretation] What can low versus high RBC, hemoglobin, or hematocrit indicate?

Low: anemia, hemorrhage, or fluid overload (RBC); low Hgb/Hct also possible in chronic illness. High: dehydration/hemoconcentration or increased RBC production.

[Lab interpretation] Why are low and high platelet counts concerning?

Low platelets (thrombocytopenia): easy bruising or spontaneous bleeding. High platelets (thrombocytosis): risk of microvascular clotting.

[Lab interpretation] What are PT, INR, and aPTT used to assess?

They measure clotting time. INR helps evaluate oral anticoagulant therapy such as warfarin. Report significant abnormalities; assess for bleeding.

[Lab interpretation] What do the ABG measurements assess?

ABGs evaluate the lungs’ delivery of oxygen to blood and elimination of CO2. Interpret pH, PaCO2, HCO3−, PaO2, and SaO2 together.

[Lab interpretation] What are the main components of a BMP compared with CMP?

BMP: glucose, Ca, Na, Cl, K, CO2, BUN, creatinine. CMP adds liver/protein tests including ALP, AST, ALT, bilirubin, albumin, total protein, globulin.

[Nursing responsibilities] What must the nurse do before obtaining a lab specimen?

Verify order and restrictions; gather supplies; identify patient; perform hand hygiene; explain test; collect, label, and store specimen correctly.

[Nursing responsibilities] What should the nurse assess after venipuncture?

Monitor the site for bleeding, hematoma, phlebitis, or infection. Review results and report significant abnormalities.

[Nursing responsibilities] What is a culture and sensitivity test used for?

Culture identifies an infectious microorganism; sensitivity helps determine which antibiotics may work. Common samples: blood, wound, sputum, urine, stool.

[Nursing responsibilities] What are key instructions for urine and stool specimens?

Urine culture: fresh sample, cleanse urethral opening, sterile cup, avoid toilet paper. Stool: clean container; do not contaminate with urine or tissue.

[Nursing responsibilities] Why do therapeutic drug levels require exact timing?

Levels show whether a drug is in a therapeutic range. Trough = lowest, just before next dose; peak = highest, usually about 1 hour postdose per lecture; follow policy.

[Diagnostic tests] What must the nurse consider before and after a diagnostic test?

Before: focused assessment, checklist, consent if needed, teaching, allergies, transport safety. After: reassess and continue teaching.

[Diagnostic tests] How do plain X-ray and fluoroscopy differ?

X-ray: static image; usually no prep, remove metal from area. Fluoroscopy: moving X-ray images, often with contrast/barium; follow test-specific prep.

[Diagnostic tests] What is the nursing care for barium fluoroscopy?

Before: fasting/prep as ordered. After: encourage fluids if allowed; stool may be white/chalky for 1–3 days; laxative may be prescribed.

[Diagnostic tests] What is essential before and after an upper GI endoscopy (EGD)?

Before: NPO 8–12 h and prepare for sedation. After: monitor vital signs, keep NPO until gag reflex returns, watch for perforation.

[Diagnostic tests] What is essential for lower GI endoscopy/colonoscopy?

Before: liquid diet and bowel prep, NPO as ordered. After: monitor vital signs while sedation wears off and assess for perforation.

[Diagnostic tests] What is ultrasound used for, and how is the patient prepared?

Uses sound waves and a transducer. May require fasting or a full bladder depending on study; usually no special follow-up. Echo assesses heart structure/flow.

[Diagnostic tests] How do you prepare a patient for CT versus MRI?

CT uses X-rays; if contrast, check renal function and reaction history. MRI uses magnet/radio waves; remove metal, screen implants; consider claustrophobia.

[Diagnostic tests] What must the nurse monitor after angiography?

After contrast/catheter study: monitor for bleeding, embolus, contrast reaction, kidney dysfunction, and sedation effects.