Equations and Conversions

All calculators:

All weight conversions are by the factor 0.4532

All height conversions use 2.54 as the factor.

Ideal body weight is calculated as [(height in inches-60) * 2.3] + 45.5 for female or + 50 for male. Don’t ask me why this equation uses inches to calculate a solution in kg. Please note this field will not report if the patient is less than 60” tall.

Adjusted body weight is (actual-ideal)*40% + ideal. Since there is some variation in how some sites adjust body weight, a few different factors are offered. More can be made available on request.

Rate calculator:

The calculator will offer sequential rates of infusion for the given drugs.

The rituximab rates are calculated assuming a total volume of 500 ml. No consideration is made for overfill and the assumption is that an equal volume of diluent will be removed prior to adding the rituximab.

This calculator does not estimate any overfill. Bag volumes are assumed to be as labeled, even though they frequently are not. There is great variability in overfill from volume to volume and manufacturer to manufacturer, so there is no real way to capture this consistently. If this is determined to be an issue, it may be possible to build some flexibility into this calculator to offer the option to factor in overfill manually. Use the Contact Us page to make any such request.

Creatinine Clearance:

Clearance is based on the selected weight. The equation is the standard cockcroft-gault as [(140-age)*wt in kg]/(72*SCr) for males, same equation but 85% for females.

Jelliffe clearance for males is (98-(0.8*(age-20)))/SCr, for females it is 90% of the same calculation.

Chemo Calculator:

Clearance is determined as above in the clearance calculator.

All doses are rounded for clinical pertinence, see rounding link for further details.

AUC is based on the Calvert equation for dosing carboplatin, so dose will be (entered target AUC)*(clearance by selected weight + 25).

All BSA are calculated based on weight in kg and height in cm:

Dubois BSA is calculated on selected body weight as follows: 0.007184 * (selected weight)0.425 * (height)0.725

Gehan and George BSA is calculated on selected body weight as follows: 0.0235 * (selected weight)0.51456 * (height)0.42246

Mostellar BSA is calculated on selected body weight as follows: 0.016667 * (selected weight)0.5 * (height)0.5

Haycock BSa is calculated on selected body weight as follows: 0.024265 * (selected weight)0.5378 * (height)0.3964