COMLEX 3 (DIT, COMBANK, MTB) Flashcards
(500 cards)
MC microorganism in exogenous endopthalmitis
Staphylococcus epidermidis (eye infection)
Endophthalmitis is an inflammation of the interior of the eye
Sensitivity equation
TP / TP + FN
screening test positive in pts with a disease
likelihood that a test will detect all people with the disease
SN-OUT - negative test, rules out disease
ifits perfectly sensitive then no false negatives
Specificity equation
TN / TN + FP
probability test will be negative in pts w/o disease
likelihood that people without disease are correctly identified as disease free by a test
SP-in - specificity, positive test rules in disease
Positive Predictive Value (PPV)
TP / TP + FP
probability someone with positive test has disease
Attributable risk calculation
AR = (A/A+B) - (C/C+D)
difference in rates between exposed and unexposed populations
Incidence equation
New cases of dz / Population at risk
Prevalence equation
of people with disease currently / total population
Compares a group of people with a given disease to a group w/o the disease
Case control
Compares a group with a given risk factor or exposure to a group without that risk factor
Cohort
Relative risk calculation
(A/A+B)/(C/C+D)
probability of getting a disease in a group exposed to specific risk factor compared to probability of getting disease in unexposed group
Absolute risk reduction
(C/C+D) - (A/A+B)
Difference in rates of disease between exposed and unexposed populations
Number needed to treat
1/ARR
ARR = (C/C+D) - (A/A+B)
number of pts that have to be treated in order to prevent one negative outcme
Standard error of mean
“sigma / square root of sample size
“
Z-value for CI = 90%
1.645
CI = [(mean - Z(SEM) to (mean + Z(SEM)]
Z-value for CI = 95%
1.96
CI = [(mean - Z(SEM) to (mean + Z(SEM)]
Z-value for CI = 99%
2.57
CI = [(mean - Z(SEM) to (mean + Z(SEM)]
Chest Pain + Pleuritic Pain (changes with respiration) DDx
Pulmonary embolism
Pneumonia
Pleuritis
Pericarditis
Pneumothorax
Ages that make cardiac family hx significant
Female relatives < 65
Male relatives < 55
S3 gallop
“Dilated Left Ventricle
"”Rapid ventricular filling during diastole””
As soon as the mitral valve opens, blood rushes into the ventricle, causing a splash sound transmitted as an S3”
S3 or Ventricular Gallop
- After S2
- Failing left ventricle, increased blood volume in ventricles
- Dilated CHF
- Ken-tuck-y
S4 gallop
Left ventricular hypertrophy
The sound of atrial systole into a stiff or noncompliant ventricle
S4 or Atrial Gallop
- Before S1
- Blood being forced into hypertrophic left ventricle
- Failing left ventricle, restrictive cardiomyopathy.
- Tenn-ess-ee
Mitral regurgitation murmur
Holosystolic
Best initial test for ischemic-like pain
EKG
Most accurate test for ischemic-like pain
Troponin or CK-MB
Which cardiac enzyme will rise first with an MI?
Myoglobin (1-4 hours)
Troponin and CK-MB will rise 3-6 hours after


