Cardiovascular- Diagnostic tests, labs, and lab values Flashcards
Diagnostic Tests: why do a chest x-ray
will reveal abnormalities of lung fluids, overall heart shape and size (cardiomegaly), aneurysm
Diagnostic Tests: myocardial perfusion imaging
- used to diagnose and evaluate ischemic heart disease, myocardial infarction
- thallium-201 scan is where thallium is injected into blood via IV; radioisotopes concentrate in normal tissue but not in ischemic or infarcted tissues (cold spots)
used to identify myocardial blood flow, areas of stress-induced ischemia (exercise test, old infarcts
-thallium stress test is used with exercise test; injected at peak exercise - Positron emission tomography (PET) uses radioactive marker 18-F-fluorodeoxyglucose (FDG)
Diagnostic Tests: echocardiogram
noninvasive test that uses US to assess internal structures- size of chambers, wall thickness, ejection fraction (EF), movement of valves, septum, abnormal wall movement
Diagnostic Tests: cardiac catherization
- passage of tiny tube via brachial or femoral artery through aorta into blood vessels; uses contrast medium and x-ray to see whats happening in coronary vessels
- gives info about anatomy of heart, vessels, valves, and any abnormalities
- can also check EF
Diagnostic Tests: Central line (Swan-Ganz catheter)
- catheter is inserted through vessels into right side of heart
- measures central venous pressure (CVP), pulmonary artery pressure (PA), pulmonary capillary wedge pressures (PCWP)
Diagnostic Tests: why select an MRI
creates a 3D image of heart to investigate coronary arteries, aorta, pericardium, and myocardium
Lab Tests: Why check changes in the enzyme troponin
rise and fall > 99th percentile is the primary measure of detecting MI
Lab Tests: What must accompany troponin value to diagnose MI
Any one of the following:
- symptoms of ischemia
- new or presumed new ST changes on ECG
- development of pathological Q waves on ECG
- new loss of viable myocardium and/or new wall motion abnormality on imaging
- evidence of intracoronary thrombus via catherization or autopsy
Lab Tests: what other enzyme level could you check
elevation of CP or CPK (serum creatine kinase or creatine phosphokinase) with concomitant elevation of CK-MB (serum creatine kinase MB) can also be assessed, but peaks between 12-24 hours
Lab Tests: purpose of serum lipid panels
used to determine coronary risk
Lab Values: Arterial Blood Gases- SpO2
- Norm 98%-100%
- SaO2 below 88%-90% usually requires supplemental O2
Lab Values: Arterial Blood Gases- PaO2
- Norm 90-100 mm Hg
- increased level = hyperoxygenation
- decreased level = cardiac decompensation, COPD, and some neuromuscular disorder
Lab Values: Arterial Blood Gases- PaCO2
- Norm 35-45 mm Hg
- increase = COPD, hypoventilation
- decrease = hyperventilation, pregnancy, PE, and anxiety
Lab Values: Arterial Blood Gases- pH, whole blood
- Norm 7.35-7.45
- increase = resp alkalosis (>7.45) = hyperventilation, sepsis, liver disease, fever
- increase = metabolic alkalosis (>7.45) = vomiting, potassium depletion, diuretics, volume depletion
- decrease = resp acidosis = hypoventilation, COPD, resp depressants, myasthenia (weakness)
- decrease = metabolic acidosis = increased acids (diabetes, alcohol, starvation); renal failure, increased acid intake, and loss of alkaline body fluids
Lab Values: Hemostasis (clotting time)- Prothrombin time
- Norm 11-15 sec
- increase detects factor X deficiency, hemorrhhagic disease, cirrhosis, hepatitis drugs (warfarin)
Lab Values: Hemostasis (clotting time)- Partial Prothrombin Time
- Norm 25-40 sec
- increase implicates factor 8, 9, and 10 deficiency
Lab Values: Hemostasis (clotting time)- International Normalized Ratio (INR)
- Reference range 0.9- 1.1
- Pts. with DVT, PE, mechanical valves, Afib, on coagulation will have target INRs of 2-3. These pts.
and those with clotting disorders may have orders for target INR 3.5 - Look for active signs of beleeding when treating these patients and use compensatory strategies to reduce risk of falling
Lab Values: Hemostasis (clotting time)- Bleeding time & C-reactive protein (CRP)
- Bleeding time norm 2-10 min
- CRP norm <10 mg/L
- increase values implicate platelet disorders, thrombocytopenia
- increased levels associated with increased risk of atherosclerosis
- > 100 mg/L associated with inflammation and infection
WBC
- Norm 4300-10,800 cells/mm3
- indicative of status of immune system
- over 10,800 = infection (bacterial or viral), inflammation, hematologic malignancy, leukemia, lymphoma, drug use (corticosteroids)
- under 4300 = aplastic anemia, B12 or folate deficiency
- with immunosuppression there is increased risk of infection
Lab Values: CBC- physical therapy considerations for abnormal WBC values
consider metabolic demands in presence of fever and use of mask when WBCs < 1000 - 2000 or Absolute Neutrophil Count (ANC) <500 - 1000
Lab Values: CBC- RBC
- norm males 4.6 - 6.2
- norm females 4.2 - 5.9
- above norm = polycythemia
- below norm = anemia
Lab Values: CBC- Erythrocyte Sedimentation Rate (ESR)
- norm male <15 mm/hr
- norm female <20 mm/hr
- above norm = infection and inflammation: rheumatic or pelvic inflammatory disease, osteomyelitis used to monitor effects of treatment eg. RA, SLE, Hodgkin’s disease
Lab Values: CBC- Hct
- hematocrit percentage of the whole blood
- norm males 45-52%
- norm females 37- 48%
- norms are age dependent
- above norm = erythrocytosis, dehydration, shock
- below norm = sever anemia, acute hemorrhage
Lab Values: CBC- PT considerations for abnormal Hct
can cause decrease in exercise tolerance, increase fatigue, and tachycardia
Lab Values: CBC- Hgb
- norm male 13-18 g/dL
- norm female 12-16 g/dL
- norms are age dependent
- above norm = polycythemia, dehydration, shock
- below norm = anemias, prolonged hemorrhage, RBS destruction (cancer, sickle cell disease)
Lab Values: CBC- PT considerations for abnormal Hgb
can cause decrease in exercise tolerance, increase fatigue, and tachycardia
Lab Values: CBC- Platelet count
- norm 150,00- 450,000 cells/mm3
- above norm = chronic leukemia, hemoconcentration
- below norm = thrombocytopenia, acute leukemia, aplastic anemia, cancer chemotherapy
Lab Values: CBC- PT considerations for abnormal Platelet count
- increased risk of bleeding with low levels so monitor for hematuria, petechiae, and other signs of active bleeding
- <20,000 AROM, ADLs only
- 20,000 - 30,000 light exercise only
- 30,000 - 50,000 moderate exercise
