Dosage Calculations for EMS Providers (Part 1)

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Dosage Calculations for EMS Providers (Part 1)

• Ray Taylor
• Valencia Community College
• Department of Emergency Medical Services

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Intravenous Infusion Calculations

• Formula
• Volume to be Infused x Administrative Set (10,
  15, 60, etc) Divided by Time in Minutes
• Practice Example
• Order 2500ml of Lactated Ringers IV in 24 hours
• Drop Factor 15gtts/ml
• Formula 2500ml x 15 26gtts/min
• 1440min
• Complete Practice Problems 1-14 Page 1 of
  Dosage Calculations Section

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Dosage Calculations

• Units of Measurements
• Apothecary
• Household
• Metric
• Most common method used in clinical medicine

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Dosage Calculations

• Metric System Fundamental Units
• Grams Mass
• Liters Volume
• Meters Distance

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Dosage Calculations

• Common units of conversion
• Grams to milligrams (x 1000)
• Milligrams to grams (divide 1000)
• Milligrams to micrograms (x 1000)
• Micrograms to milligrams (divide 1000)
• Grains to milligrams (x 60)
• Milligrams to grains (divide 60)

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Dosage Calculations

• Common units of conversion
• Liters to milliliters (x 1000)
• Milliliters to liters (divide 1000)
• 1 milliliter 1 cubic centimeter (consider
  equivalent)
• 1ml of water occupies 1cc of space

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Dosage Calculations

• Pounds (lb) to Kilograms (kg)
• Formula
• Patients weight in pounds divided by 2.2
• Example
• 150lb patient divided by 2.2 68kg
• Assignment Complete practice problems on pages
  3-5 in the dosage calculations workbook

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Dosage Calculations forEMS Providers (Part 2)

• Ray Taylor
• Valencia Community College
• Department of Emergency Medical Services

9
Dosage Calculations

• Master Formula
• Desired Dose divided by the concentration on hand
  x Vehicle
• or
• Order divided by the supply x Vehicle
• Vehicle is the volume of liquid in which the
• supply is contained

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Dosage Calculations

• Master Formula
• Example 1 (page 7 in workbook)
• Order 30mg Demerol IM
• Supply Demerol 50mg/ml
• Step 1 Evaluate order and supply
• Ensure same unit measurement
• 30mg 0.6ml
• 50mg/ml

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Dosage Calculations

• Master Formula
• Example 2 (page 7 in workbook)
• Order Streptomycin 250mg IM
• Supply 0.5gm/2ml
• Step 1 Evaluate order and supply
• Order in mg and supply in gm
• Always convert supply to same unit of measurement
  as the order
• 0.5 gm x 1000 500mg/2ml
• Calculate
• Order 250mg x 2ml 1ml
• 500mg

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Dosage Calculations

• Examples
• Order Kantrex 150mg IM
• Supply Kantrex 0.5gm/2ml
• Order Sodium phenobarbital 100mg IM
• Supply Sodium phenobarbital 125mg/2ml

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Dosage Calculations

• Assignment
• Complete the practice problems on pages 7 16 in
  the dosage calculations worksheets