Medical Calculator with Equations and Interpretations

Note that this is still being tested. I will remove this message when the formulas/formatting is finalized.
Alveolar-Arterial O2 Gradient = FiO2 * (pAtm - pH2O) - paO2 - pCO2 / RQ =
  pAtm = 760 mmHg * exp(-altitude / 7000)
  pH2O = 47 mmHg @ 37 degrees Celcius   FiO2 (%):
  altitude (Sacramento is 7 meters):
  paO2 (mmHg):
  pCO2 (mmHg):
  RQ (respiratory quotient):

Anion Gap = Na - (Cl + HCO3) =
  Na:   Cl:   HCO3:
  normal = 8 - 16
  if high, remember MUDPILES (Methanol, Uremia, Dka, Paraldehyde, INH/Iron, Lactic acid, Ethanol, Salicylates)

APGAR =
  color: pink   extremities blue   body blue
  tone: active   some flexion   limp
  pulse: HR >= 100   < 100   no pulse
  respiration: crying   irregular respirations or slow   absent
  response to suction: sneeze or cough   grimace   no reaction
  most babies 7-10, points off for color and tone

Corrected Calcium = Ca + 0.8 * (4 - Alb) =
  Ca:   Alb:

Child-Pugh Score =
Bilirubin: <2 2-3 >3
Albumin: >3.5 3.5-2.8 <2.8
PT prolongation (INR): <4 seconds (<1.7) 4-6 seconds (1.7-2.3) >6 seconds (>2.3)
Ascites: Absent Mild-Moderate Severe/Refractory
Encephalopathy: Absent Mild (I-II) Severe (III-IV)

  Class A = 5-6, Class B = 7-9, Class C = 10-15

Creatinine Clearance (Cockcroft-Gault) =
  (M) 1.23 * weight * (140 - age) / Cr
  (F) 1.03 * weight * (140 - age) / Cr   gender: Male   Female
  weight (kg):   age (years):   Creatinine (mg/dL):

Corrected Na = Na + (glc - 5) / 3.5 =
  Na (mmol/L):   glc (mg/dL):

Fractional Excretion of Sodium, FENa (%) = (UNa / UCr) * (PCr / PNa) =
  Na, plasma (mmol/L):   Cr, plasma (mmol/L):   Na, urine (mmol/L):   Cr, urine (mmol/L):
  < 1% --> Prerenal

Free Water Deficit =
  (M) 0.5 * kg * ((Na / 140) - 1)
  (F) 0.4 * kg * ((Na / 140) - 1)
  gender: Male   Female
  weight (kg):   Na (mmol/L):
  max 1/2 deficit replace in 1st 24hrs

Fluid Replacement, Parkland formula (L) = weight * % BSA burned * 4 =
  weight (kg):   % Body Surface Area burned (%):
  1/2 first 8hrs, 1/2 next 16hrs

Glomerular Filtration Rate, GFR =
  = 186 * Cr ^ -1.154 * age^-0.203 * 1.210 (if black) * 0.742 (if female)
  = 170 * Cr ^ -1.007 * age^-0.180 * 1.178 (if black) * 0.755 (if female) * BUN ^ 0.169
  = 170 * Cr ^ -0.999 * age^-0.176 * 1.180 (if black) * 0.762 (if female) * BUN ^ 0.17 * alb ^ 0.318
  gender: Male   Female
  African-American ethnicity?:
  age (years):
  BUN (units):
  Cr (mg/dL):
  alb (units):

Osmotic Gap = measured osmolals - 2 * Na + BUN / 2.8 + glc =
  measured Osmolals (units):   Na (mmol/L):   BUN (units):   glc (mg/dL):

delta-delta =
  Na:   Cl:   HCO3 (units):   alb:
  delta HCO3 = 24 - HCO3 =
  expected AG = albumin x 2.5 =
  AG = Na - (Cl + HCO3) =
  delta AG = AG - expected AG =
  delta-delta = delta HCO3 - delta AG
    delHCO3 ~ delAG, ~0 --> pure AG metabolic acidosis
    delHCO3 > delAG, >0 --> simultaneous non-AG acidosis
    delHCO3 < delAG, <0 --> simultaneous metabolic ALKalosis

Glasgow Coma Scale, adults =
  Eye opening (none/pain/speech/spontaneous)
  Verbal communication (none/sounds/words/confused/oriented)
  Motor (none/abnormal extension/abnormal flexion/withdraw pain/localize pain/spontaneous or obeys commands)
  < 8 is coma


LDL goals from ATP III:
Major CHD Risk Factors:
    Cigarette smoking
    Hypertension
    HDL<40
    age (man >45, female >55)
    family history of premature CHD (male age <55, female age <65)

LDL goals based on # risk factors:
    0-1     <160
    2+       <130
    CHD   <100

Criteria for choosing a lipid lowering agent:
Drug%LDL reduction%HDL increase%TG reductionSide Effects (monitoring & contraindications)
statin18-555-157-30myopathy, increased LFT
sequestrant15-303-5nil - increaseGI, constipation, decreased drug absorption
Niacin5-2515-3520-50flushing, hyperglc, gout, LFT, UGI
fibric acid5-2010-2020-50dyspepsia, gallstones, myopathy, (LFT, Cr)
Criteria for SIRS
  2 or more of HR>90,
  T<36 or T>38,
  RR >20 or PaCO2 <32,
  WBC <4 or >12
More formulas to be added. . . and will be organized by specialty? body system? pih interpretation Sabai protocol anemia lab interpretation - the whole mas gen book!!! BMR (harris-benedict) kcal/day = men: = 13.7516 * kg + 5.0033 * cm - 6.755 * yrs + 66.473 women: = 9.5634 * kg + 1.8496 * cm - 4.6756 * yrs + 655.0955 IBW (Robinson formula) kg = men: = 52 + 1.9 * (in - 60) women: = 49 + 1.7 * (in - 60) BMI Immunization calculator/calendar