**How Calculations Work**

This documentation is intended to guide you through the various calculators available on the site. These calculators are all driven by client-side JavaScript, ensuring transparency of calculations. To review the code behind the calculations, simply right-click anywhere on the page and select "view page source".

**Pediatric Dose Calculator**

Our Pediatric Dose Calculator is specifically designed to compute Intravenous (I.V.) dosages for children aged between 0 to 12 years and weighing from 3 to 45 kg. The calculated dosages are displayed up to 2 decimal places, and they are rounded off to the nearest .0, .25, .5, or .75 for practicality. However, please be aware that this rounding-off does not apply to final dosages that are under 1.

Additional Features

**HR and RR**: The calculator provides standard estimates of heart rate (HR) and respiratory rate (RR) for a healthy, awake, and resting child.

**Tidal Volume** (VT): The VT is calculated based on a standard of 6 - 8 ml/kg.

**Maintenance Fluids**: These are calculated using a variant of the Holliday-Segmar formula. Note that this calculation does not take into account factors like preoperative fasting (NPO) or perioperative blood loss.

For weights 0 - 10 kg: 3 ml/kg/hr

For weights 11 - 20 kg: 30 ml + 1 ml/kg/hr

For weights above 20 kg: 40 ml + 0.5 ml/kg/hr

**DC Cardioversion**: The dosage for DC cardioversion is calculated by multiplying the child's weight (in kg) by 4.

**ETT and LMA Sizes**: Provided for uncuffed tubes. Please be aware that the suggested sizes might not fit all patients.

**Local Anesthetic Calculator**

This calculator assists in determining weight-based local anesthetic dosages (expressed in mg/kg). If the input weight is in pounds (lb), it will automatically convert this to kilograms (kg) by multiplying the lb weight by 0.45359237. The final dosages are then displayed up to 2 decimal places and are rounded off to the nearest .0, .25, .5, or .75.

**Hourly Fluids Calculator**

The Hourly Fluids Calculator estimates the hourly fluid requirements for patients weighing 60kg/132 lbs or more. It takes into account the patient's body weight, the duration of preoperative fasting, and the estimated surgical fluid losses. The calculation assumes NPO losses replaced over 3 hours, with 50% in the first hour, and 25% for each of the subsequent two hours.

The calculator uses the Holliday-Segmar formula and applies the following rates:

For weights 0 - 10 kg: 4 ml/kg/hr

For weights 11 - 20 kg: 40 ml + 2 ml/kg/hr

For weights above 20 kg: 60 ml + 1 ml/kg/hr

As in other calculators, if the input weight is in lb, it converts this to kg (by multiplying the lb weight by 0.45359237) before estimating fluid needs.

**IBW, LBW, and BMI Calculator**

This calculator provides estimates for Ideal Body Weight (IBW), Lean Body Weight (LBW), and Body Mass Index (BMI) using the following formulas:

**IBW**: For males, it is the height (in cm) - 100; for females, it's the height (cm) - 105.

**LBW**: For males, LBW = 0.407 * weight + 0.267 * height - 19.2; for females, LBW = 0.252 * weight + 0.473 * height - 48.3.