CALCULATING DRUG DOSAGES
A PATIENT-SAFE APPROACH TO NURSING AND MATH
SECOND EDITION
Glossary of Terms
absorption (drug): The process by which a substance/drug enters into the bloodstream.
ADD-Vantage® system: A special IVPB that has a vial of a powdered medication attached to the top
of the IV bag. The medication is released into the IV fluid just before administration.
adverse drug reaction (ADR): An unintended and harmful response to a drug.
adverse drug event (ADE): An injury that occurs from a drug. The injury may include physical harm,
mental harm, or loss of function.
adverse effects: Undesired harmful effects associated with a drug or treatment.
ambulatory pump: A small, lightweight infusion pump that is powered by a battery and allows
mobility for the patient. Battery powered ambulatory pumps are set in mL/hr.
analogs: Insulin analogs are genetically altered from synthetic human insulin. The main analog
insulin types include rapid-acting insulin and long-acting insulin.
anterior iliac crest: The curved ridge bone located along the upper most border of the ilium of the
pelvis.
antimicrobial preservatives: Preservatives that contain a chemical substance that inhibits or
prevents the growth of microorganisms over time.
apothecary system: An outdated and obsolete system of weight and measures that consist of units
such as the grain, dram, ounce, and pound. The non-decimal apothecary system has been
replaced by the metric system.
barrel: The body of the syringe that holds the medication.
basal (insulin): Insulin that is released slowly and steadily throughout the day. Types of basal insulin
include the long-acting insulin such as Levemir and Lantus.
Beers Criteria: A guide that lists potentially inappropriate medications that should be used with
caution or avoided in the older adult because of physiological age-related changes.
bevel: The sharp, slanted end of a needle.
beyond-use date: The last date that an opened vial can be used. The Joint Commission, the
organization that accredits hospitals and health care organizations, requires that multidose
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vials be discarded 28 days after first use unless the manufacturer specifies otherwise (shorter
or longer).
body surface area: A measurement of the total surface of a patient’s body measured in meters
squared (m2). Body surface area takes into account both the height and weight of the patient.
bolus (insulin): The type of insulin that works rapidly and may be administered several times a day
depending on the blood glucose. Types of bolus insulin include the rapid-acting and fast-acting
insulin such as Novolog, Apidra, Humalog, and Regular insulin.
bladder irrigation: The infusion of a sterile solution into the bladder through a special indwelling
urinary catheter for the purpose of cleansing the bladder or instilling medication.
brand name: The name given to the drug by a specific drug manufacturer, also known as the
proprietary name or trade name. The symbol ® is found next to the brand name.
BSA: Abbreviation for “body surface area.”
calibration lines: The lines on the barrel of the syringe that are used to measure medication doses.
caplet: A small tablet coated with a smooth covering that makes it easier to swallow.
capsules: A drug enclosed in a gelatin-like covering that holds the powder or form of the drug.
central IV: A central IV is an IV that is inserted into a large vein near the heart, such as the
subclavian or jugular vein. A central IV can be inserted directly through the chest wall, or
threaded through a peripheral vein into a large vein (in which case it is called a peripherally
inserted central catheter, or PICC line).
coated (tablet): A special coating applied to the tablet. The tablet may be sugar coated, film coated,
gelatin coated, or enteric coated. Each type of coating is designed for a specific purpose, such
as to facilitate swallowing, enhance taste, protect tablet from environment, or prevent the
release of the active ingredient in the stomach.
colostomy: An opening through the abdominal wall that allows a portion of the large intestine (the
colon) to be brought out to the surface of the abdomen.
completion time: The time in hours and minutes when the ordered amount of IV fluid has
completely infused into the patient.
concentration: The amount of an active ingredient that is in a specific volume of a liquid
preparation.
continuous feeding: The administration of formula feeding administered continuously into a
patient’s feeding tube through a feeding pump.
conversion: To change a unit of measurement to an equivalent unit of measurement.
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conversion factor: Two equivalent measurements expressed as a fraction. Conversion factors are
used in the dimensional analysis method to cancel unnecessary units of measurement in a
dosage calculation.
conversion table: A listing of equivalent units of measurements from the metric and household
systems.
convert (in math): To change a unit of measurement to an equivalent unit of measurement.
cross multiplication: The multiplication of the numerator of one fraction by the denominator of the
other fraction. Cross multiplication is used to solve dosage calculations in the fractional ratio
and proportion method.
culture of safety: A continuous awareness by all health care workers of actions needed to promote
patient safety and encourage collaboration among all health care staff to seek solutions to
system-wide patient safety problems.
dead space: The space where a small volume of medication is retained (in the needle, hub, and tip
of a syringe) after the plunger is fully depressed.
decimal number: A number that uses a decimal point to separate the ones place from the tenths
place. Numbers to the right of the decimal point have a value less than one.
desired amount: The amount or volume of drug to be administer; the answer to the unknown in a
mathematical equation.
diabetes mellitus: Diabetes mellitus is a metabolic disease that affects the body’s ability to use
glucose.
diluent: A liquid that dilutes a substance (e.g., powdered medication) and makes it less
concentrated than its original form. A liquid substance added to a powdered medication to mix
and dissolve it.
dilution: The process of decreasing the concentration of another substance.
displacement: The increase in volume when a liquid is added to a powder or solid (i.e., the
displacement that occurs when a dissolved powdered medication takes up space).
distribution: The process of a drug being distributed to the body fluids and tissues.
dosage: The quantity of a drug to be taken over time, such as 10 mg T.I.D.
dosage form: The form (solid, liquid) that holds the strength or concentration of a medication.
dosage strength: The strength and dosage form of a medication.
dose: The amount of drug to be administered at one time (e.g., 10 mg).
duodenum: Part of the gastrointestinal system—specifically, the part of the small intestine that is
connected to the stomach.
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drip chamber: A flexible enlargement in the IV tubing that allows a clear view of the drops of IV
fluid infusing through the tubing.
drop factor: The number of the drops per mL delivered from an IV tubing.
duration (insulin): The time the injected insulin continues to lower blood glucose in the body. The
duration varies with the different types of insulin.
drug-drug interaction: Alteration of the action or therapeutic effect of a drug with the simultaneous
use of another drug (prescription or nonprescription), resulting in the increase or decrease in
the desired drug effect. This may put the patient at risk for a drug reaction.
drug-nutrient/drug–natural product interaction: Interference with the action of a drug when
nutrients or natural products interact with the drug, contributing to an increase or a decrease
in the absorption, metabolism, distribution, or excretion of the drug.
effective dose: A dose is considered effective when the amount of drug is enough to produce the
desired therapeutic effect.
elastomeric balloon pump: An ambulatory IV pump that works by positive pressure inherent in the
balloon.
elixir: A liquid drug mixture consisting of water, alcohol, and flavored subtances designed for oral
use.
emesis: Vomiting.
enteral: The route used to deliver nutrition or medications through the gastrointestinal tract (e.g.,
administration of formula through a feeding tube).
enteral nutrition: A method of providing nutrients to the gastrointestinal system through a feeding
tube.
enteric coating (EC): A tablet with a special coating that allows the tablet to be released after a time
delay. The enteric-coated tablet is designed to break down after passing the stomach. Entericcoated tablets should not be crushed or broken.
excretion (drug): The process of elimination of the drug from the body.
expiration date: The last day that an unopened vial or medication can be used. The date beyond
which the potency of a medication cannot be guaranteed.
flow rate: The mL/hr set on an IV infusion pump or the number of drops per minute (gtt/min) for an
infusion of IV fluid by gravity.
formula method: A mathematical process for solving drug dosage calculations using a formula:
D
 Q=x
H
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fractional (ratio and proportion): A method of calculating drug dosage problems that sets up a
proportion as a fraction.
fraction thereof: A part of the whole, or a fractional amount of the whole.
gastric: Pertaining to the stomach.
gauge: A measurement of the diameter of a needle.
generic name: The universal chemical or pharmacological name of the drug. A drug has only one
generic name.
geriatric: Relating to the older adult.
gram: The base unit of measurement for mass (weight) in the metric system.
greater trochanter: The large protuberance on the outside of the upper end of the femur.
half-life (drug): The time it takes for one-half of the strength of a drug to be eliminated from the
body.
HD: Abbreviation for “hourly drug.”
HV: Abbreviation for “hourly volume.”
heparin lock: A short IV line that is attached to an IV catheter. The IV lock can be flushed with saline
or with heparin to keep the IV line patent.
high alert (medications): A medication that has an increased potential for patient harm; signifies
the need for health care professionals to be vigilant in the preparation of the ordered dose, in
the administration of the drug, and in monitoring the patient for the drug’s effects.
hormone: A chemical substance secreted by a gland in the body and transported by the blood to
specific organs or tissues. Hormones help to control or regulate the function of the organ or
tissue.
household system of measurement: A system of measurement that includes the volumes of
commonly used items, especially kitchen utensils, as they are applied to administering
medications.
human insulin: Synthetically produced insulin that resembles the structure of the natural insulin
made by the beta cells of the pancreas.
ID: Intradermal
ileostomy: An opening through the abdominal wall that allows the ileum, the lowest portion of the
small intestine, to be brought out to the surface of the abdomen.
infusion time: The time (hours and minutes) it takes to infuse the ordered amount of IV fluid.
injection port: Part of the IV tubing that allow needleless entry into the IV tubing.
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intake (oral): The measurement of any food that is liquid or that turns into liquid at room
temperature, such as ice cream and gelatin. Intake is recorded in mL.
I & O: Abbreviation for “intake and output.”
infiltration (IV): The displacement of an IV needle or cannula from the vein allowing fluid to infuse
into the surrounding tissue.
inhalant: A medication that is inhaled through the mouth or nose into the respiratory tract for
absorption.
intradermal (ID): Under the skin or dermis.
IM: intramuscular
intermittent feeding: The administration of a specific amount of formula given through the
patient’s feeding tube on a fixed schedule (e.g., every 4 hours, every 6 hours, etc.).
intramuscular (IM): Into the muscle.
intravenous (IV): Into the vein.
irrigant: A solution used for irrigating and washing. Bladder irrigation requires the use of a sterile
irrigant solution such as 0.9% Sodium Chloride Irrigation, USP.
IV: Abbreviation for “intravenous.”
IV catheter: A small plastic tube that is inserted into a vein for the administration fluids and
medications directly into the circulatory system.
IV infusion by gravity: The infusion of IV fluid using gravity to promote flow. The flow rate (gtt/min)
of an IV infusion by gravity is regulated by a roller clamp on the IV tubing.
IV infusion pump: An electronic device that is programmed to deliver IV fluids and medications at
precisely controlled rates.
IV lock: A short IV line that is attached to an IV catheter. The IV lock can be flushed with saline
(“saline lock”) or with heparin to keep the IV line patent.
IV piggyback (IVPB): A small-volume IV used to administer IV medications; also referred to as a
secondary IV.
jejunostomy: The opening into the middle of the small intestine, the jejunum. The procedure is
done for the placement of a feeding tube (jejunostomy tube, J-tube).
jejunum: Part of the gastrointestinal system. The jejunum is the middle part of the small intestine
that follows the duodenum.
just culture: A non-punitive approach for identifying and analyzing factors and the sequence of
actions that led to a medical error. The primary focus of this approach is to learn how best to
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prevent similar errors in the future by looking for systematic solutions rather than blaming
individuals.
known ratio: The ratio in a proportion that includes the information known, such as the
information on the drug label.
leading zero: A zero placed before a decimal point used with fractional decimal numbers (e.g., 0.1).
In health care, a leading zero is always placed before a decimal fraction.
linear (ratio and proportion): A method of calculating drug dosage problems that sets up
proportions in a linear format.
List of Error-Prone Abbreviations, Symbols, and Dose Designations: A listing published by the
Institute for Safe Medication Practices that identifies abbreviations, symbols, and dose
designations that may be misinterpreted and lead to medication errors. Items on this list
should be avoided in communicating medical information.
liter: The base unit of measurement for volume in the metric system.
look-alike (sound-alike): Refers to drug name pairs that look alike and sound alike, have the
potential to be confused with each other, and may lead to a medication error.
lumen: The hollow opening inside an object or tube (e.g., double-lumen urinary catheter).
macrodrip: IV tubing that delivers large drops. The common drop factors (drops per mL) of
macrodrip IV tubing are 10 gtt/mL, 15 gtt/mL, and 20 gtt/mL.
maintenance IV fluids: IV fluids and electrolytes used to maintain fluid and electrolyte balance in
the body.
medication pass time-out: A safety strategy in medication administration that allows the nurse to
take time early in the shift to review, question, and check medications before preparing the
patient’s medication.
meniscus: The curved center that is formed when the surface tension of a measurement device
allows liquid to flow up the walls, forming a concave center. For accurate measurement, it is
important for the nurse to read a liquid measurement at the bottom of the curved surface of
the meniscus.
metabolism (drug): The process by which a substance/drug is transformed so that it can be
excreted from the body. Excretion of the drug can occur through various routes, including the
kidneys, intestine, lung, bile, and breast milk.
meter: The base unit of measurement for length in the metric system.
metric line: A horizontal line that lists the base units of measurement and the prefixes and symbols
for the purpose of converting between the metric units of measurement by the movement of
the decimal point.
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microdrip: IV tubing that delivers small drops. The only drop factor (drops per mL) of a microdrip IV
tubing is 60 gtt/mL.
milliequivalent (mEq): A unit of measurement that indicates the concentration of an electrolyte per
liter of solution.
minim: A volume of measurement from the apothecary system, approximately the size of drop; not
a precise unit of measurement and no longer used in the health care setting.
Mix-O-Vial®: A special two compartment vial in which the medication is in one compartment and
the diluent in another compartment. The two compartments are separated by a rubber
stopper that can be pushed, allowing the diluent and powder to mix together.
mL for mL: IV fluid replacement that is equal to the volume of fluid lost through drainage. For
example, if 450 mL of nasogastric fluid drains from the patient, 450 mL is replaced through an
IV infusion.
multiple-strength reconstitution: Reconstitution of medications that have more than one
designated volume of diluent to use for diluting the medication. The nurse may choose
between a more dilute or more concentrated mixed medication. The dosage strength is
dependent on the volume of diluent added.
nasogastric: From the nose to the stomach (i.e., nasogastric tube).
no interruption area: A safety strategy in medication administration that designates a specific area
(zone) for the preparation of medications. The “no interruption area” represents a concerted
effort by health care facilities to minimize interruptions and distractions as the nurse prepares
the ordered medications.
nomogram: A graph or chart that shows the relationship between different numerical variables,
such as height and weight.
Nomogram for Children of Normal Height for Weight: A graph included in the West Nomogram
used to determine the body surface area only by the weight of the child. This nomogram can
be used if a child is of normal height for his or her weight as determined by standardized
growth and development charts.
non-electric pump: Non-electric disposable pumps, such as elastomeric balloon pumps, are IV
pumps designed for ambulatory use. These pumps work by positive pressure inherent in the
balloon. No infusion rate is set on an elastomeric balloon pump.
non-parenteral: Introduction of a nutrition or medication into the body by the gastrointestinal
route (i.e., mouth, stomach, intestine, rectum).
onset (insulin): The time it takes for injected insulin to start lowering the blood glucose in the body.
Onset varies with the different types of insulin.
ordered amount: The dose (amount and unit of measurement) ordered by a health care provider.
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output: The measurement of liquid drainage produced by the body such as urine, diarrhea, and NG
tube drainage. Output is measured in mL.
pancreas: The gland in the body responsible for producing several hormones and enzymes including
the hormone insulin.
paracentesis: A procedure that involves the insertion of needle or catheter into the abdominal
peritoneal cavity to remove excess serous fluid (ascites).
parenteral: Any medication administration route that does not use the gastrointestinal tract to
deliver drugs. The common parenteral routes include intramuscular (IM), subcutaneous
(subcut), intradermal (ID), and intravenous (IV).
parenteral intake: The measurement of fluid administered by the IV route, such as the fluid intake
from primary IVs and IVPBs.
parenteral nutrition: The administration of intravenous nutrition. The intravenous nutrition
contains, proteins, carbohydrates, fats, vitamins, minerals, and other substances to meet the
nutritional needs of the individual patient.
patent: Open, not obstructed. A term used to indicate that an IV, catheter, or tube is not obstructed
and is working properly.
PCA pump (patient-controlled analgesia pump): An IV pump that has a feature that allows the
patient to self-administer medication by pushing a button on the pump. A PCA pump is a
specialized type of syringe pump.
peak (insulin): The time when an injected insulin is at its maximum level for lowering the blood
glucose in the body. The peak time varies with the different types of insulin.
peripheral IV: An IV catheter or IV needle that is inserted through the skin into a vein. Common
peripheral IV sites include the hand or arm.
peripheral line: An IV tubing connected to a peripheral IV site.
PICC (peripherally inserted central catheter): A central IV inserted through a peripheral vein and
threaded into the large vein near the heart, usually the subclavian vein.
plunger: The rubber-tipped cylinder that fits inside a syringe and fills and empties the syringe.
point of care: Any location where patient care is provided, for example, the bedside, emergency
room, clinic, or ambulance. The consideration to the safe delivery of care and services specific
to the needs of the individual patient.
polypharmacy: The use of multiple medications, including prescription medications, over-thecounter medications, vitamins, and herbal preparations.
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Potentially inappropriate medications (PIM): Medications that have an increased risk for toxicity in
the older adult because of physiological age-related changes. These medications should be
used with caution or avoided in the older adult. One listing of PIMs is known as the Beers list.
prefilled syringe: A syringe containing a specific volume of medication prepared by the drug
manufacturer. The prefilled syringe cartridge contains all of the information found on a drug
label.
preservative: A substance added to a drug to prevent physical, chemical, or biological changes to
the drug.
preservative free: Absence of a preservative in a drug.
primary IV: A large-volume IV used to administer fluids and electrolytes to the patient on a
continuous basis.
primary IV infusion set: A long plastic IV tubing with an enlarged section at the top, called the drip
chamber, and several injection ports. The clear plastic tubing connects directly to the IV bag
and allows IV fluid to flow into the IV catheter or to the saline lock.
product: The mathematical answer obtained from the multiplication of two numbers.
proportion: A mathematical equation that expresses that two ratios are equal.
proprietary name: The name given to a drug by a specific drug manufacturer, also known as the
brand name or trade name. The symbol ® is found next to the proprietary name.
rate of administration (IV push): The time, in seconds or minutes, identified by the drug
manufacturer, in which an IV medication can be safely administration by the IV push route.
ratio: A mathematical expression that indicates that two numbers are related to each other.
recommended dose: The dose of a medication that safely achieves a particular therapeutic effect.
The recommended dose is determined by the drug manufacturer.
reconstituted: To restore to liquid form by adding water.
reconstitution: A process that involves mixing a powdered medication with a liquid (diluent) to
achieve a specific concentration. The nurse needs to follow the reconstitution directions
provided by the drug manufacturer exactly to arrive at the correct dosage strength for the
mixed medication.
remaining amount (IV fluid): The amount of IV fluid in the IV bag that remains at the close of intake
and output for the shift.
replacement IV fluid therapy: Replacement of IV fluid, water, and electrolytes needed because of
abnormal losses such as excessive drainage from wounds, burns, vomiting, and diarrhea.
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right documentation: One of the Six Rights of Medication Administration that directs the nurse to
document, in the patient’s medication administration record, all the medications given to the
patient. Documentation is done immediately after the administration of the medication.
right dose: One of the Six Rights of Medication Administration that requires the nurse to check that
the correct dose of a medication is being administered. This is done by comparing the
medication available from the pharmacy with the medication order. Checking for the right
dose is done in conjunction with checking for the right drug.
right drug: One of the Six Rights of Medication Administration that requires that the drug be
checked three times (compare the drug from pharmacy with the patient’s medication
administration record (MAR), before putting the medication into the medication
administration device, and again before administering the drug to the patient).
right patient: One of the Six Rights of Medication Administration that requires the nurse to use
approved processes for identifying the patient, such as checking two patient identifiers before
administering any medication or treatment.
right route: One of the Six Rights of Medication Administration that directs the nurse to confirm the
ordered route in conjunction with the process of checking for the right drug.
right time: One of the Six Rights of Medication Administration that directs the nurse to administer
scheduled drugs on time and administer PRN (as-needed) drugs within the ordered frequency.
Risk Evaluation and Mitigation Strategy (REMS): A risk management program monitored by the
U.S. Food and Drug Administration that helps to ensure that the benefits of a specific drug or
drug class outweigh the risks. Part of the REMS program requires drug manufacturers to
include drug monographs to keep consumers informed of the effects and adverse effects of
the drug.
safe dose: A dose is considered safe when the amount of drug is equal to or less than the dose
recommended in the drug reference.
saline lock: A short IV line that is attached to an IV catheter. The IV lock is flushed with saline to
keep the IV line patent.
sentinel event: An unexpected occurrence that may involve the death of the patient or has the risk
of great psychological or physical harm to a patient.
scored tablet: A tablet with indented lines that allows the tablet to be split into equal parts. Each
part of the tablet will contain an equal amount of the active ingredient of the drug.
secondary IV infusion set: A short IV tubing specifically designed to “piggyback” into the primary
line through an injection port.
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single-strength reconstitution: Reconstitution of medications that have one designated volume of
diluent to add to dilute the medication. With single-strength reconstitution there is only one
resulting dosage strength.
Six Rights of Medication Administration: The process for the safe preparation and administration
of medications. The Six Rights of Medication Administration guide the nurse to identify the
right dose, right dose, right route, right patient, right time, and right documentation.
solution (oral liquid medication): A homogeneous mixture of two or more substances that remain
mixed and stable and will not separate over time.
sterile: Free of any living microorganisms; aseptic.
strength (of a drug): The amount of drug in a specific physical form (e.g., tablet, capsule, mL, etc.).
syringe cartridge: A cartridge containing a specific amount and dosage strength of medication
prepared by the drug manufacturer. A syringe cartridge needs a special holder (usually with a
plunger) to administer the medication.
subcutaneous (subcut): Into the subcutaneous tissue; beneath the skin.
syrup: A drug in a viscous liquid preparation consisting largely of purified water and sucrose or a
sugar substitute for a more pleasant taste.
suspension: A liquid that contains small particles of a drug that cannot be dissolved. Suspensions
need to be shaken well to ensure thorough mixing before administration.
syringe pump: A motor-driven IV pump that pushes the plunger of a syringe to deliver a small
volume of fluid or high-potency medication at a precise rate of infusion. The rate on a syringe
pump is set at mL/hr.
TD: Abbreviation for “total drug.”
TV: Abbreviation for “total volume.”
tall man lettering: The use of mixed case letters (lower- and uppercase) in a drug name with the
specific purpose of highlighting a section of the drug name to distinguish similar drug names,
making them less prone to mix-up (e.g., chlorproMAZINE and chlorproPAMIDE).
therapeutic index: The difference (margin of safety) between the minimum amount of a drug to be
considered a safe dose and the maximum amount of a drug that will produce undesirable or
toxic effects. The margin between a safe dose and a toxic or lethal dose.
thoracentesis: A procedure that involves the insertion of needle in the space between the chest
wall and the lung tissue (pleural cavity) to remove fluid or air.
titration (IV): The adjustment (increasing or decreasing) of the rate of an IV infusion to achieve a
desired physiological response in the patient.
tissue necrosis: The death of body tissue.
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titration: The process of adjusting a medication dose by increasing or decreasing the rate of an IV
infusion to achieve a desired physiological response in the patient.
topical: Applied to the skin or mucous membrane.
trade name: The name given to the drug by a specific drug manufacturer, also known as the
proprietary name or brand name. The symbol ® is found next to the brand name.
trailing zero: A zero placed at the end of a decimal fraction—for example, 0.50. To prevent
medication errors, the Institute for Safe Medication Practices discourages the use of trailing
zeros.
unit: An expression of the biological activity or potency of a substance that brings about a specific
biological response in the body. Some medications, such as heparin, insulin, and penicillin are
measured in units.
unit dose: One dose of a medication.
unit of measurement: The method by which a quantity of measure is expressed (e.g., inch, foot,
second, hour).
uncoated (tablet): Tablets with no outer coating that disintegrate in the gastrointestinal tract.
unknown ratio: The ratio in a proportion that contains the “x” or the unknown.
urinary catheter: A tube inserted through the urethra into the bladder. The urinary catheter drains
the urine from the bladder.
vastus lateralis: The largest muscle from the quadriceps group located on the side of the thigh.
ventrogluteal: A recommended site for IM injections. The ventrogluteal site consists of both the
gluteus medius and gluteus minimus muscles and is located halfway between the anterior iliac
crest and the greater trochanter.
viscosity: Thickness; resistant to flowing freely.
voiding: The act of passing urine.
voided: The act of having urinated.
volumetric pump: An electronic infusion device that pumps a set volume of IV fluid using special
tubing. The rate on a volumetric pump is set at mL/hr.
weight-based dosing: The use of weight to calculate a drug dose (e.g., 1 mg/kg).
West nomogram: A weight- and height-based nomogram.
zero line: The first line on the barrel of a syringe.
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