Medical Dosage Calculations For Dummies E-Book

Richard Snyder

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 472

Veröffentlichungsjahr: 2011

Beschreibung

Score your highest in a medical dosage calculations course A recent shortage of nurses in a society with an aging population has triggered the demand for students to enter the field of medical study. A dosage calculations course is required for most students earning an applied science degree in nursing, pharmacology, or paramedic programs. Medical Dosage Calculations For Dummies tracks a typical dosage calculations course and provides helpful content in an approachable and easy-to-understand format. Plus, you'll get examples of the various calculations made to determine the appropriate quantity of drug or solution that should be administered to patients. * Calculating drug dosages utilizing ratio-proportion, formula, and dimensional analysis * Systems of measurement, including metric and apothecary and other conversion equivalents for a global audience * The ins and outs of the charting systems for MAR (Medicine Administration Records) If you're one of the hundreds of thousands of students aspiring to enter the medical field, Medical Dosage Calculations For Dummies is your ticket for scoring your highest on exams.

Leseprobe

Medical Dosage Calculations For Dummies®

Visit www.dummies.com/cheatsheet/medicaldosagecalculations to view this book's cheat sheet.

Table of Contents

Introduction

About This Book

Conventions Used in This Book

What You’re Not to Read

Foolish Assumptions

How This Book Is Organized

Part I: Getting Up to Speed: Reviewing Math Basics

Part II: Minding Your Meds: Administration and Calculation Methods

Part III: Calculations for Different Routes of Administration

Part IV: Dosing in Special Situations

Part V: The Part of Tens

Icons Used in This Book

Where to Go from Here

Part I: Getting Up to Speed: Reviewing Math Basics

Chapter 1: Brushing Up on Your Math Skills and Entering the Healthcare Field

Knowing What Math You Need to Know in Healthcare

Nailing down basic arithmetic

Fiddling with fractions in four forms

Conquering the calculation methods

Living in a metric world

Tools of the Trade for Dosing Meds

Surveying Healthcare Careers (They All Use Medical Math!)

Looking at the classic nursing careers

Probing other medical careers

Examining emergency medicine

Offering help at home

Beyond the Math: Remembering the Human Side of Healthcare

Chapter 2: Using Numbers and Arithmetic

Healthy Numbers: Surveying the Numeral Systems Used in Healthcare

Representing the classics: Roman numerals

Making math a lot easier: Arabic numerals

Looking at where you see numbers in medicine

Ingesting a Dose of Numbers

Visualizing numbers on the number line

Zeroing in on zero: It’s really nothing

Using Addition to Make Everything Add Up

Seeing Subtraction in Action

Do be a borrower and a lender

Working with positive and negative numbers

Managing Multiplication

Making multiplication easier with a few shortcuts

Getting the lowdown on metric units

Doing Division: Divided We Stand

Real-Life Practice: The RN and the Meds

Real-Life Practice: A Fluid Approach to Fluids

Real-Life Practice: Liquid Assets

Chapter 3: Getting Familiar with Fractions and Their Fanatic Forms

Using Fractions to Probe between Integers

Common fractions

Decimal fractions

Percentages

Proportions (and ratios)

Conquering Fraction-Related Conversions

Converting fractions into decimals

Converting decimals into fractions

Converting percentages into decimals

Converting decimals into percentages

Converting percentages into fractions

Converting fractions into percentages

Playing the Percentages

Calculating percentage increases

Calculating a 100% increase

Calculating percentage decreases

Real-Life Practice: Chow Down to Heal Up

Real-Life Practice: Measuring the Mass

Chapter 4: Getting Familiar with Systems of Measurement and Unit Conversions

Looking at the Main Measurement Systems Used in Medicine

Metric system

United States customary system

Household system

Apothecaries’ system

Examining the Rules of Conversion

Knowing the conversion factor

Converting to identical units

Converting Units in Different Measurement Systems

Converting metric to metric

Converting metric to American

Converting American to American

Converting American to metric

Converting apothecaries’ units to metric

Converting temperature

Real-Life Practice: Filling Up on Fluids

Real-Life Practice: Sipping on Syrup

Part II: Minding Your Meds: Administration and Calculation Methods

Chapter 5: The Prescription: Just What the Doctor Ordered

Comparing Written versus Electronic Prescriptions and Patient Charts

The traditional written word

The electronic medical record

Identifying the Essential Ingredients of a Good Prescription

Patient identification

Correct spelling

Clear, correct dosage

Timed and dated legible signature

Location, Location, Location: Knowing the Route of Administration

Timing Is Everything: Knowing When and How Often to Give a Med

Medical abbreviations for time

The 24-hour clock: Military time

Individualized Dosing Modifications

Verbal Orders: Make like a Parrot and Repeat Them to the Doctor

Real-Life Practice: Interpreting Orders

Real-Life Practice: Evaluating a Script

Chapter 6: Medication Labels and Patient Safety

Anatomy of a Medication Label

Brand and generic names

Supply dosage strength or concentration

Form

Route of administration

Total volume

Bar code

National Drug Code number

Directions for reconstituting

NF or USP quality assurance

Manufacturer’s name and lot number

Combination medications

Controlled substance classifications

Expiration date

Label alerts and FDA drug alerts

Highlighting the Four Big Patient Safety Concerns

Checking for medication allergies

Asking about adverse drug reactions

Dealing with drug-drug interactions

Dealing with a mix of herbal and traditional

Reviewing the Six “Rights” of Medication Administration

Right patient

Right medication

Right dose

Right time

Right route

Right documentation

Two more rights for patients

Chapter 7: Proper Medical Documentation and Dispensation

The Medication Reconciliation Form — Essential for Patient Care

The Medication Administration Record — Don’t Mar Your MAR!

Knowing where to find the MAR

Understanding what’s in the MAR

Reviewing Medication Dispensation

Tubing up the meds

Using the Pyxis to give narcs

Real-Life Practice: Administering a Narcotic

Real-Life Practice: Checking Vitals and Administering Fluids

Chapter 8: Mastering Calculation Methods for Dosing Meds

Taking a General Approach to Dosage Calculations

Knowing some basic mathematical principles

Following the process

Using the right tools

Focusing on the Formula Method

Relying on the Ratio-Proportion Method

Dosing with the Dimensional Analysis Method

Real-Life Practice: Using Various Methods for Common Dosage Calculations

Determining total flushes

Figuring out how many amoxicillin tablets to administer

Giving a potassium chloride piggyback

Figuring the dose and total volume of an antibiotic

Administering furosemide in mL

Figuring the dosage of phenobarbital

Part III: Calculations for Different Routes of Administration

Chapter 9: Oral Calculations: Tablets, Capsules, and Liquids

Checking Out the Label

Examining and Dosing Tablets

Splitting scored tablets

Needing to crush — The tablet, not the person

Giving timed-release tablets

Protecting the tummy with coated tablets

Dosing tablets

Considering the Colorful Capsule in Medical Dosing

Shelling out for a capsule

Calculating dosages for capsules

Looking at Liquids and Knowing How to Dose Them

Surveying the different types of liquids

Dosing liquid meds

Converting from One Form of a Med to Another

Going from intravenous to oral (and back again)

Converting between meds with the same purpose

Administering to the Patient with a Feeding Tube

Real-Life Practice: Doxycycline, the Infection Fighter

Real-Life Practice: In Need of Potassium

Chapter 10: Parenteral Injections and Calculations

Packing a Syringe — It’s Essential to be Equipped

Anatomy of a syringe

Surveying several syringe types

Using the right syringe to inject a med

Getting the med into the syringe

Looking At the Label and Following Hospital Protocols

Practicing Parenteral Dosing Calculations

Subcutaneous dosing: Getting under the skin

Intradermal dosing: Feeling the wheal

Intramuscular dosing: Going straight for the muscle

Real-Life Practice: Dosing an IM Med

Real-Life Practice: Dosing a Subcutaneous Med

Chapter 11: The IV League: Intravenous Dosing and Calculations

Infusion 101: Calculating Flow Rates, Infusion Times, and Drip Rates

Going with the flow: Calculating the flow rate

Timing is everything: Calculating the infusion time

IV drips and drops: Using the drop factor to calculate drip rate

Taking a Closer Look at IV Systems

Beginning with the IV bag

Going with gravity: Manual IV systems

Getting pumped up: Automated IV systems

Dosing Heparin, Insulin, and Other Infusions

Real-Life Practice: Finding the Drip Rate of a Dose of Albumin

Real-Life Practice: Calculating Infusion Time for D5W

Real-Life Practice: The Heparin Bolus and Maintenance Infusion

Chapter 12: Working with Reconstituted Solutions: It’s like Magic

When Solute Met Diluent: A Love Story

The components

The instructions

The method

Working through the Process of Reconstitution

Reconstituting single-strength meds

Using the right concentration of a multiple-strength medication

Storing leftover meds

Real-Life Practice: Reconstituting and Dosing Olanzapine

Real-Life Practice: Figuring the Dosage of Reconstituted Ampicillin

Real-Life Practice: Reconstituting and Dosing a Multiple-Strength Medication

Part IV: Dosing in Special Situations

Chapter 13: Insulin: Call It a Miracle Drug

Getting the Lowdown on Diabetes and Insulin

Monitoring blood glucose

Typecasting insulin

Measuring Insulin in Units

Getting the Most from the Dose with an Insulin Syringe

Combining Insulins

Using the Sliding Scale for Insulin Doses

Avoiding Confusion with the Continuous Infusion

Real-Life Practice: Administering an Insulin Infusion to Treat DKA

Real-Life Practice: Adjusting Insulin Levels Based on Glucose Levels

Chapter 14: Dosing for Two: The Pregnant Patient

Calculations for Pregnancy-Related Situations

Reducing hypertension

Preventing eclampsia

Stopping early contractions

Inducing labor

Monitoring Mom and Junior When Administering Meds

Checking Mom’s vitals and examining her body

Using the fetal monitor to keep an eye on the baby

Dealing with Medications That Aren’t Related to the Pregnancy

Checking for contraindications

Minimizing the number and amount of meds pregnant women take

Real-Life Practice: Treating Hyperemesis Gravidarum

Real-Life Practice: Fighting Infection by Wiping Out the Germs

Real-Life Practice: Wiping Out Even More Germs

Chapter 15: Kid Stuff: Pediatric Calculations

Realizing the Dosing Differences from Child to Child and Adult to Child

Weighing and Going Metric: Dosing Meds for Kids

Using weight when you calculate

Dosing safely for kids’ safety

Trying Another Way: Calculating BSA

Considering Some Other Rules of Dosing

Clark’s rule

Fried’s rule

Young’s rule

Looking at Special Considerations for Four Routes of Administration

Managing IV Fluids for Infants and Children

The kilogram bands

Counting calories

Using the BSA

Being Extra Careful When Administering Meds or Fluids Intravenously

Real-Life Practice: Determining Whether an Ordered IV Dosage Is Safe

Real-Life Practice: Figuring a Ped Patient’s Fluid Needs

Real-Life Practice: Safely Administering an IV Infusion

Chapter 16: Adjusting Dosages for People in Special Situations

Keeping Up with the Kidneys

Dosing considerations and changes for folks with kidney disease

Dealing with dialysis

Dosing for Liver Disease

Leveling the Playing Field

Dosing for Patients Who Malabsorb Meds and Nutrients

Dosing with bowel diseases in mind

Factoring in other causes of decreased absorption

Dosing for the Elderly

Considering the changing body physiology

Knowing the albumin level

Dosing smaller, not bigger

Being on the lookout for harmful drug interactions

Real-Life Practice: Checking for Drug Interactions

Real-Life Practice: Dosing Meds to a Patient on HD

Chapter 17: Critical Care Dosing and Calculations

Being Prepared for Intensive Work in Intensive Care

What to expect in the ICU

What to do to stay ahead of the game

Raising a Shockingly Low Blood Pressure

Dealing with acid buildup

Infusing pressors when other fluids aren’t enough

Titrating the dose

Lowering Skyrocketing High Blood Pressure

Leading with labetalol

Exploding with nitro

Dosing Meds That Fight Heart Failure

Calculating the dosage of epinephrine

Figuring the dosages for milrinone

Treating a Dysrhythmia

Administering continuous infusions to treat dysrhythmia

Giving a little push

Helping with Heparin

Real-Life Practice: Calculating Flow Rates of Nitroglycerin and Furosemide

Real-Life Practice: Finding the Initial Flow Rate for Nicardipine

Real-Life Practice: Determining theFlow Rate for Vasopressin

Chapter 18: Keeping a Patient Well-Nourished

Being Aware of a Patient’s Caloric Needs

Feeding through a Tube

Administering enteral nutrition

Including free water flushes

Feeding through the Veins

Replacing Low Electrolytes

Measuring in milliequivalents

Minding the millimoles when giving phosphorus

Real-Life Practice: Administering Furosemide and Replacing Lost Electrolytes

Real-Life Practice: Calculating a Patient’s Total Input

Part V: The Part of Tens

Chapter 19: Ten Essential Dosing Calculations

Converting lb to kg and kg to lb

Converting mL to L and L to mL

Converting mg to g and g to mg

Calculating the mg Dose of Oral Meds

Calculating the mL Dose of Liquid Meds

Calculating Infusion Rates

Calculating Infusion Times

Calculating Infusion Volumes

Doing Parenteral Dosing Calculations

Doing Unit-Based Dosing Calculations

Chapter 20: Ten Ways to Avoid Common Dosing Mistakes

Watch Out for Meds That Sound Similar

Avoid Ambiguous Abbreviations

Assess a Med’s Applicability

Minimize Metric Mistakes

Check Infusion Rates

Avoid Measurement System Conversion Errors

Get the Timing Right When You Administer

Review the Allergies and ADEs

Don’t Forget the “Rights” of Medication Administration

Communicate!

Cheat Sheet

Medical Dosage Calculations®

by Dr. Richard W. Snyder, DO, and Barry Schoenborn

Medical Dosage Calculations®

Published byWiley Publishing, Inc.111 River St.Hoboken, NJ 07030-5774www.wiley.com

Copyright © 2011 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400, fax [phone]. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, [phone], fax [phone], or online at http://www.wiley.com/go/permissions.

Trademarks: Wiley, the Wiley Publishing logo, For Dummies, the Dummies Man logo, A Reference for the Rest of Us!, The Dummies Way, Dummies Daily, The Fun and Easy Way, Dummies.com, Making Everything Easier!, and related trade dress are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates in the United States and other countries, and may not be used without written permission. All other trademarks are the property of their respective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in this book.

Limit of Liability/Disclaimer of Warranty: The contents of this work are intended to further general scientific research, understanding, and discussion only and are not intended and should not be relied upon as recommending or promoting a specific method, diagnosis, or treatment by physicians for any particular patient. The publisher and the author make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of fitness for a particular purpose. In view of ongoing research, equipment modifications, changes in governmental regulations, and the constant flow of information relating to the use of medicines, equipment, and devices, the reader is urged to review and evaluate the information provided in the package insert or instructions for each medicine, equipment, or device for, among other things, any changes in the instructions or indication of usage and for added warnings and precautions. Readers should consult with a specialist where appropriate. The fact that an organization or Website is referred to in this work as a citation and/or a potential source of further information does not mean that the author or the publisher endorses the information the organization or Website may provide or recommendations it may make. Further, readers should be aware that Internet Websites listed in this work may have changed or disappeared between when this work was written and when it is read. No warranty may be created or extended by any promotional statements for this work. Neither the publisher nor the author shall be liable for any damages arising herefrom.

For general information on our other products and services, please contact our Customer Care Department within the U.S. at 877-762-2974, outside the U.S. at 317-572-3993, or fax [phone].

For technical support, please visit www.wiley.com/techsupport.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Library of Congress Control Number: 2011924132

ISBN: 978-0-470-93064-9

Manufactured in the United States of America

10 9 8 7 6 5 4 3 2 1

About the Authors

Dr. Rich Snyder, DO, is an osteopathic physician who resides in Easton, Pennsylvania. He’s a kidney specialist, board certified in both internal medicine and nephrology. He did his Internal Medicine Residency at Abington Memorial Hospital and completed both clinical and research fellowships in nephrology at the Hospital of the University of Pennsylvania. He also has experience in graduate medical education. As a former associate program director and osteopathic program director at Easton Hospital, he was responsible for both the administration and education of medical residents and medical students.

In addition to maintaining a full time clinical practice at Lehigh Valley Nephrology Associates, he has authored and coauthored several articles in peer-reviewed journals, including the American Journal of Kidney Disease and Kidney International. He has also presented at national meetings, including the National Kidney Foundation’s Annual Meeting. In addition to being a coauthor of Medical Dosage Calculations For Dummies, he has written the book What You Must Know About Kidney Disease: A Practical Guide to Conventional and Complementary Treatments. He’s also been interviewed regionally and nationally on both radio and television about integrative medicine and kidney disease. Beginning in January 2011, he can be heard weekly on his show, Improve Your Kidney Health, on VoiceAmerica Radio Health and Wellness Channel.

Barry Schoenborn lives in Nevada City, California. He’s a longtime technical writer, with over 30 years’ experience. He’s written hundreds of user manuals, and (in the early days) worked dozens of part-time jobs that required practical and scientific math. Mathematics and engineering were among his college majors until he abandoned them to earn a degree in Liberal Arts.

He isn’t a doctor and tries to avoid being hospitalized. However, he’s spent many hours undergoing dental procedures, which sparked an ongoing interest in dentistry and medicine. He’s the author of the short stories, “Doc Jones, Frontier Dentist,” “Doc Jones, Combat Dentist,” and “Murder, She Flossed.”

In the past, Barry’s technical writing company worked with the State of California agency CalRecycle to teach scientists and administrators how to write clearly. Barry’s the coauthor of Technical Math For Dummies and Storage Area Networks: Designing and Implementing a Mass Storage System.

He was a movie reviewer for the Los Angeles Herald-Dispatch newspaper and wrote a monthly political newspaper column for The Union newspaper of Grass Valley, California, for seven years. Barry’s publishing company, Willow Valley Press, published Dandelion Through the Crack, which won the William Saroyan International Prize for Writing.

Dedication

Rich Snyder

This book I dedicate to my mother, Nancy Snyder, herself a registered nurse and constant source of inspiration and encouragement.

I also dedicate this book to every nurse, every healthcare provider, and every caregiver out there. You are the unsung heroes and the ones that inspire hope and healing.

I finally dedicate this book to Dr. Hatem Amer, MD, a kidney specialist and best friend who is himself a rarity: His empathy and compassion is as vast as his brilliance. I consider myself lucky to call him a friend.

Barry Schoenborn

I’d like to dedicate this book to James H. Jones, DDS, my periodontist. Jim recently retired and has been an inspiration for more than 20 years. During that time, I underwent numerous periodontal procedures, fighting the ravages of oral pathogens. I learned a lot of Latin from Jim, and he always explained to me what he was doing and why. He also inspired me to write “dental humor,” a funny genre that nobody except a dentist would want to read.

Authors' Acknowledgments

Rich Snyder

I would not have been able to write this book without the heroic efforts of Barry Schoenborn. He is a gifted and talented writer, and I have learned much from him in a short amount of time. I want to thank Erin Calligan Mooney for the opportunity to coauthor this book. I also wish to thank Chrissy Guthrie and Amanda Langferman for their help and support. I also want to thank Matt Wagner for his help and continued support.

Finally, I would like to thank everyone at Lehigh Valley Nephrology Associates for being the great people they are to work with. Many happy years to come!

Barry Schoenborn

This book wouldn’t have been possible without the tremendous effort of coauthor Rich Snyder. It’s amazing how much he knows! We were supported by a great team at Wiley Publishing (Chrissy Guthrie, Erin Calligan Mooney, and Amanda Langferman), who worked hard to make this book a reality. They’re very talented and also happen to be the nicest people you’ll ever meet! A big thanks, too, to Matt Wagner of Fresh Books Literary Agency, who presented us to Wiley.

Many thanks to my two favorite family practice physicians. Dr. Sara J. Richey seems to know everything, always listens, and believes in “treating the whole patient.” Dr. Jon R. Pritchett also seems to know everything, has an excellent approach to doctoring, and has shared an experience or two from his days as an emergency room doctor.

And, finally, my sincere thanks and apologies to the respiration therapist, nurses, medical assistants, and front office staffs whom I flooded with questions.

Rich and Barry

We would like to acknowledge and thank the following for their help and assistance: Christopher Vancheri and Roche Pharmaceuticals; Marcia Diljak and Eisai Pharmaceuticals; Ron Granish and X-Gen Pharmaceuticals; and Doretta Gray, Cindy Rockoff, et al from Novo Nordisk Pharmaceuticals.

Publisher’s Acknowledgments

We’re proud of this book; please send us your comments through our online registration form located at http://dummies.custhelp.com. For other comments, please contact our Customer Care Department within the U.S. at 877-762-2974, outside the U.S. at 317-572-3993, or fax [phone].

Some of the people who helped bring this book to market include the following:

Acquisitions, Editorial, and Media Development

Senior Project Editor: Christina Guthrie

Acquisitions Editor: Erin Calligan Mooney

Copy Editor: Amanda Langferman

Assistant Editor: David Lutton

Technical Editors: Kathryn E. Humphrey, MSN, RN, and Patricia Roark, RN, BSN

Editorial Manager: Christine Meloy Beck

Editorial Assistant: Rachelle Amick

Art Coordinator: Alicia B. South

Cover Photos: © iStockphoto.com/pixhook

Cartoons: Rich Tennant (www.the5thwave.com)

Composition Services

Project Coordinator: Sheree Montgomery

Layout and Graphics: Timothy Detrick, Andrea Hornberger, Lavonne Roberts, Corrie Socolovitch, Christin Swinford

Proofreaders: Sossity R. Smith

Indexer: Ty Koontz

Publishing and Editorial for Consumer Dummies

Diane Graves Steele, Vice President and Publisher, Consumer Dummies

Kristin Ferguson-Wagstaffe, Product Development Director, Consumer Dummies

Ensley Eikenburg, Associate Publisher, Travel

Kelly Regan, Editorial Director, Travel

Publishing for Technology Dummies

Andy Cummings, Vice President and Publisher, Dummies Technology/General User

Composition Services

Debbie Stailey, Director of Composition Services

Part I

Getting Up to Speed: Reviewing Math Basics

In this part . . .

Part I is a review of math basics, just in case you missed a concept or two during your education. Chapter 1 stresses the importance of dosage calculations in all healthcare professions. Chapter 2 is a fun and simple review of numbers and arithmetic. In Chapters 3 and 4, you get important basics for medical math — fractions, systems of measurement, and unit conversions.

Chapter 1

Brushing Up on Your Math Skills and Entering the Healthcare Field