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NURSE MATH

Dosage Calculations

There are many online resources for nursing students.  One of the most helpful is RegisteredNurseRN.com.

 

It is important to memorize the metric system.

The metric system uses grams, meters and liters (usually in milligrams (mg) for medications and milliliters (mL) for fluids.

Use a conversion table that lists conversions for the metric system and includes household measurements like ounces, cups, teaspoons and tablespoons.

There are many free online resources like Quizlet (digital flash cards), Nurselabs.com  and YouTube videos.

 

For beginning nurse students, here's a comprehensive video on dosage calculations and other resources: 

 

Nursing Math Cheat Sheet

1. Conversion Factors:

  • 1 kg = 2.2 lbs

  • 1 L = 1,000 mL

  • 1 oz= 30 mL

  • 1 tsp = 5 mL

  • 1 tbsp = 15 mL

  • 1 cup = 240 mL

2. Medication Calculations:

  • Dosage Calculation Formula:Ordered Dose=Available Dose×VolumeConcentrationOrdered Dose=ConcentrationAvailable Dose×Volume​

  • IV Flow Rate Calculation:Flow Rate (mL/hr)=Volume (mL)Time (hours)Flow Rate (mL/hr)=Time (hours)Volume (mL)​

3. Drug Administration:

  • Oral Medications:

  • Ensure proper patient identification.

  • Use an oral syringe for liquid medications.

  • Administer with or without food as directed.

  • Intramuscular (IM) Injections:

  • Use the appropriate needle length and gauge.

  • Administer in a Z-track method.

  • Rotate injection sites.

  • Subcutaneous (SC) Injections:

  • Pinch the skin and inject at a 45-degree angle.

  • Rotate injection sites.

  • Use a shorter needle for subcutaneous injections.

4. IV Medication Administration:

  • Drip Rates:

  • Calculate the number of drops per minute using the prescribed rate.

  • IV Bolus:

  • Administer medication over a specified time.

  • Calculate the infusion rate based on the prescribed time.

  • IV Push:

  • Administer a small volume of medication directly into the IV line.

  • Ensure compatibility and dilution if needed.

5. Pediatric Dosage Calculations:

  • Child's Dosage:Child’s Dose=Age in YearsAge + 12×Adult DoseChild’s Dose=Age + 12Age in Years​×Adult Dose

  • Body Surface Area (BSA): BSA (m²)=(Height (cm)×Weight (kg)3600)BSA (m²)=(3600Height (cm)×Weight (kg)​)​

6. Intravenous (IV) Fluids:

  • Maintenance Fluids:

  • Calculate daily fluid requirements based on weight.

  • Adjust for additional losses (e.g., vomiting, diarrhea).

  • Dilution of Solutions:Concentration=Amount of DrugVolume of SolutionConcentration=Volume of SolutionAmount of Drug​

7. Temperature Conversion:

  • Celsius to Fahrenheit: F=95C+32F=59​C+32

  • Fahrenheit to Celsius: C=59(F−32)C=95​(F−32)

8. Metric Conversions:

  • Converting Units:

  • Move the decimal point to the right or left based on the conversion factor.

  • Converting Between Units:Desired Unit=Given Unit×Conversion FactorOriginal Conversion FactorDesired Unit=Original Conversion FactorGiven Unit×Conversion Factor​

Remember to double-check all calculations, use appropriate units, and consider patient safety in medication administration. Always follow institutional policies and guidelines when performing nursing math calculations.

List of Medications 

 

While the specific medications administered by Licensed Vocational Nurses (LVNs) can vary based on patient needs and healthcare settings, LVNs commonly administer a range of medications. Here is a list of some medications that LVNs may frequently administer:

  • Acetaminophen (Tylenol):

    • Used for pain relief and reducing fever.

  • Ibuprofen (Advil, Motrin):

    • Nonsteroidal anti-inflammatory drug (NSAID) for pain and inflammation.

  • Aspirin:

    • Analgesic and antiplatelet medication.

  • Morphine:

    • Opioid analgesic for moderate to severe pain.

  • Amoxicillin:

    • Antibiotic used to treat bacterial infections.

  • Ceftriaxone (Rocephin):

    • Antibiotic for a broad spectrum of bacterial infections.

  • Insulin:

    • Used for managing diabetes.

  • Heparin:

    • Anticoagulant to prevent blood clots.

  • Warfarin (Coumadin):

    • Anticoagulant to prevent blood clots.

  • Metformin:

    • Oral antidiabetic medication.

  • Lisinopril:

    • Angiotensin-converting enzyme (ACE) inhibitor for hypertension.

  • Atorvastatin (Lipitor):

    • Statin medication for managing cholesterol levels.

  • Furosemide (Lasix):

    • Diuretic used to treat fluid retention.

  • Albuterol:

    • Bronchodilator for treating respiratory conditions.

  • Docusate Sodium (Colace):

    • Stool softener used to relieve constipation.

  • Ondansetron (Zofran):

    • Antiemetic to control nausea and vomiting.

  • Citalopram (Celexa):

    • Selective serotonin reuptake inhibitor (SSRI) for depression.

    • Diphenhydramine (Benadryl):

    • Antihistamine used for allergic reactions and as a sedative.

  • Cephalexin (Keflex):

    • Antibiotic for bacterial infections.

  • Hydrochlorothiazide (HCTZ):

    • Diuretic for hypertension and fluid retention.

  • Lorazepam (Ativan):

    • Benzodiazepine used for anxiety and sedation.

  • Dexamethasone:

    • Corticosteroid for anti-inflammatory and immunosuppressive effects.

  • Loratadine (Claritin):

    • Antihistamine for allergy relief.

  • Ranitidine (Zantac):

    • Histamine-2 blocker used for gastric acid reduction.

  • Naloxone:

    • Opioid antagonist used to reverse opioid overdose.

It's important to note that LVNs work under the supervision of registered nurses or physicians, and the administration of medications is based on healthcare provider orders. Additionally, LVNs should adhere to medication administration protocols, verify patient information, and monitor for any adverse effects. The specific medications administered will depend on the patient's medical condition, treatment plan, and overall healthcare needs.

 

 

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