HY Equations

eesohbel's version from 2015-08-08 21:28

Section 1

SensitivityTP/(TP + FN)
SpecificityTN/ (TN + FP)
Positive Predictive Value TP/ (TP + FP)
Negative Predicative ValueTN/ (FN + TN)
Odds ratio(a/c)/(b/d)
relative risk a/(a+b)/c/(c+d)
attributable risk a/(a+b)-c/(c+d)
attributable risk reduction c/(c+d)-a/(a+b)
relative risk reduction 1-RR
Number needed to treat 1/ARR
Number needed to harm 1/AR

Section 2

Half LIfe(.693 x Vd)/CL
Volume of distribution amount of drug in the body/plasma drug concentration
maintenance doseplasma concentration x clearance

Section 3

COSV X HR
COrate of O2 consumption/ (arterial O2 content - venous O2 content)
Stroke volumeSV=EDV-ESV
MAPcardiac output x TPR
SVEDV-ESV
EFSV/EDV
for graphs look at TPR first

Section 4

capillary fluid excahngeKf[(Pc-Pi)-(ONCOTICc-ONCOTICi)
Renal clearanceUxV/P
for renal clearance if Cnet reabsorption of substance
for renal clearance if C>GFRnet secretion of substance
GFRUinuliin x V/P inulin
GFRkf(Pgc-Pbs-Oncoticgc)
FFGFR/RBF
WINTERS1.5 (HCO3) plus 8 plus or minus 2

pulmonary

alveolar gas equationPIo2 - Paco2/R
minute ventilationtidal volume times breaths/min
alveolar ventilation(tidal volume-dead space volume) times breaths/min

RENAL FORMULAS

renal clearance formulaCx = UxV/Px
what is used as a proxy for GFR?creatinine clearance(inulin is most perfect tho)
what is used as a proxy for RPF?PAH clearance
general GFR formulaKf[(Pgc - Pbs) - (πgc - πbs) --> remember that πbs is normally 0 bc no protein in filtrate
RBF formulaRPF/(1 - Hct)
eRPF formulaeRPF = Upah x V/Ppah = Cpah
FFGFR/RPF
what is number 1 indicator of diabetic nephropathy?albuminuria
normal clearance variations in pregnancy?glucosuria and aminoaciduria bc decreased ability of PCT to reabsorb these
AA constrictiondecreased GFR, decreased RPF, no change FF
EA constrictionincreased GFR, decreased RPF, increased FF
increased plasma protein concentrationdecreased GFR, no change RPF, decreased FF
decreased plasma protein concentrationincreased GFR, no change RPF, increased FF
ureter constrictiondecreased GFR, no change RPF, decreased FF
anion gap formulaNa - (Cl + HCO3)
winters formulafor metabolic acidosis compensation --> PCO2 = 1.5 (HCO3-) + 8 +/- 2