Introduction to Pharmacology Math for Surgical Technologists

Summary

Key Points

• Milligrams per milliliter (mg/ml) indicates drug strength, where a higher mg/ml means a stronger concentration, often used for liquid medications. 1:22
• Drugs measured in "units," like Heparin, have a wide range of concentrations (e.g., 10 units/ml to 20,000 units/ml), demanding extreme caution due to similar appearances of vastly different strengths. 1:29
• Percentages are commonly used for local anesthetics (e.g., Lidocaine), where 1% is equivalent to 10 milligrams per milliliter, and the total injected volume must be tracked to avoid toxicity. 18:11
• Ratios, such as 1:1000 or 1:100,000, describe highly diluted or concentrated drugs like Epinephrine, where a larger second number indicates a weaker concentration. 22:59
• Highly concentrated drugs like 1:1000 Epinephrine are extremely potent and typically reserved for topical use or emergency situations, while weaker dilutions (e.g., 1:100,000) are used for injection with local anesthetics. 31:40
• Pharmacology calculations, including ratio and proportion or the standard dilution equation (C1V1 = C2V2), are essential tools for accurately converting and preparing medications to desired concentrations and volumes. 35:38
• The C1V1 = C2V2 formula allows for calculating the volume of a concentrated drug needed to achieve a specific diluted concentration and volume, which is vital for preparing solutions like heparinized saline. 37:10
• Medications are supplied in various forms, including milligrams per milliliter, units, percentages, and ratios, each requiring specific understanding for safe administration. 40:52
• Understanding the different concentrations and supply methods is crucial to prevent severe medication errors, as exemplified by past incidents involving confusion between 10 units/ml and 10,000 units/ml Heparin. 40:52