Clinical Skills II Exam 1 - Intro lecture

capacity to identify all individuals with the disease is

sensitivity of a lab test

the effectiveness of a test to identify those without a disease is

specificity of a lab test

likelihood that a positive test result identifies someone with a disease is the

positive predictive value

true positives/(tru positives + false positivies) x100

positive predictive value

likelihood that a negative test identifies someone without a disease is the

negative predictive value

true negatives/(tru negatives + false negatives) x100

negative predictive value

_____ of a disease reflects the number of existing cases in a population in a period of time

prevalence

_____ refers to the number of new cases occurring within a period of time, usually 1 year

incidence

_____ refers to the ability to test one sample and repeadly obtain results that are close to each other

precision

im testing sugar myself and my sugar is 100mg/dl. i am continuously measuring it every ocupel minutes and the rate is the same, but another brand says by glucose fluctuates a lot over a short period of time. the second glucometer lacks what

precision

______ reflects the relationship between number obtained and the true result

accuracy

my glucose is 130 but this glucometer says 270. the machine lacks what

accuracy

most lab errors occur during what phase

pre-analytical phase

what are the two common errors occurring during pre analytical phase

failing to properly identify the pt and improperly transporting the specimen

this is the time that the sample is being analyzed in the lab

analytical phase

why is the analytical phase have less errors

automation

what lab phase is when the result is generated and ends when the result is reported to the physician

postanalytical phase

common routine test ordered to evaluate health status. lavender topped vacuum tube

CBC

when a pts neutrophils are inc that indicates what`

a bacterial infection

what a pts eosinophils are inc that indicates what

they picked up something from a tropical country

when taking a CBC the phlebotomist shakes the tube violently. what happens to the sample

the RBC lyse.

why are womens CBC count lower than men

bc of menstrual losses.

pt presents to ed with total loss of coronary blood low what dz do they have

STEMI

pt presents to ER with a less severe necrotic process in his heart leading to partial loss of coronary perfusion. what dz do they have

NSTEMI

what MIs are type 1

STEMI and NSTEMI bc of atherosclerosis

what type of MI is from a condition other than CAD, like coronary endothelial dysfunction, respiratory failure, hypotension, etc. secondary to ischemic imbalance

type II

what are the sx needed to dx MI

hx of chest pain, changes in ECG, and/or elevations of serial cardiac biomarkers like CK or CK-MB

what are the changes in an EKG that you see in an MI

t wave changes, elevation of st segment, q wave changes

what cardiac markers can be seen in the blood to indicate MI

total CK and CK-MB, cTnl (troponin I) and cTnT (troponin T)

what troponin is only found in the heart muscle and is a higher level

cTnI

which troponin is found int eh heart muscle and in small amounts in other muscles

cTnT

which troponin lasts longer in blood

cTnT

which troponin is a more specific marker for coronary heart dz and CVD, where the other is more associated with risk of death in non cardiovascular causes

cTnI, cTnT more non CVD

plaque rupture, intraluminal coronary artery thrombus formation is an injury related to what

primary myocardial injury

tachyarrhythmias/bradyarrhythmias, aortic dissection or severe aortic valve dz, hypertrophic cardiomyopathy, cardiogenic, hypovolemic, or septic shock, severe respiratory failure, severe anemia, HTN w or w/o LVH, coronary spasm, coronary embolism or vasculitis, coronary endothelial dysfunction without significant CAD. these are all injuries related to what

supply/demand imbalance of myocardial ischemia

cardiac confusion, surgery, ablation, pacing, or defibrillator shocks. rhabdomyolysis w cardiac involvement, myocarditis, cardiotoxic agents: anthracyclines, Herceptin. these are all injury not related to

myocardial ischemia. cTnT is elevated mostly here

heart failure, stress (takotsubo) cardiomyoapthy, severe pulmonary embolism or pulm HTN, sepsis and critically ill patients. renal failure, severe acuter neruo dz, stroke, subarachnoid hemorrhage, infiltrative dz like amyloidosis, sarcoidosis, and strenous exercise. are what type of myocardial injury

multifactorial or indeterminate

spontaneous MI is what class type 

type I

MI secondary to ischemic imbalance is what class type

type II

MI resulting in death when biomarker values are unavailable is what type of MI

type III

MI related to percutaneous coronary intervention (PCI) is what type of MI

type 4a

this MI is related to stent thrombosis is what type of MI

type 4b

in a fib what troponin is more elevated

cTnT

pt presents with chest pain onset for 2 hours but has unremarkable ECG. what do you order to rule out AMI

cTn

pt presents 2-6 hours after chest pain began. ECG is unremarkable. what do you order to rule out AMI

serial monitoring of cTn and ECG changes,

pt presents with chest pain for more than a day. ecg is unremarkalble. what do you test them for

test for cTn to find MI. provides late diagnostic time

pt presents to ed and you want to rule out AMI. when do you order tests

immediately when they get there, 3-6 hrs, then 9-12 hrs

why do you order biomarkers for a pt with ischemia

to determine the extend of the damage and see who is more at risk for AMI and death, leading to quicker surgical intervention.

pts presents to the ED any time after onset of ischemic sx with clear ECG evidence of AMI, either STEMI or Q-wave MI. do you order troponins

not needed, can do for completeness

pt presents to ED with sx similar to CHF. what tests do you order

brain natriuretic peptide (BNP, active) and NT-proBNP (not active)

why do we use NP for CHF

to rule out a new CHF

ingestion of excess or atherogenic dietary fat, which is usually saturated fatty acids and cholesterol. these are causes of what dz

atherosclerotic vascular dz

how to determine LDL cholesterol

use a fasting sample with a triglyceride level less than 400. Friedewald formula to calculate LDL. Calculated LDL cholesterol = total cholesterol - HDL cholesterol - (triglycerides/5).

what are some nonlipid d/o causing elevations in conc of plasma lipids

hypothyroidism, nephrotic syn, liver dz, diabetes, obesity, and alc abuse

this d/o that is associated with damage to the blood vessel wall can put pts at a higher risk for atherosclerotic dz by inc what AA

homocysteine

How do determine VLDL.

triglycerides/5. this is assuming there is very little triglyceride in LDL and HDL

what does total cholesterol consist of

the sum of HDL LDL VLDL IDL cholesterol, and cholesterol asociated with LP(a).

what cholesterols do we not typically test for bc its in such small amounts

IDL and Lp(a)

what is a hs-CRP test

blood test that mneasures low levels of C reactive protein in blood. if a pt has an inflammatory process. indicates risk of CV events

hs-CRP less than 1.0 represents what

low risk

hs-CRP 1.0-3.0 indicates

intermediate cv risk

hs-crp greater than 3 indicates

hi cv risk