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Comprehensive Notes on IV Pumps, Medication Administration, and Dosage Calculations

IV PUMPS, MEDICATION ADMINISTRATION, AND DOSAGE BASICS

  • IV pumps (Alaris) overview

    • Pumps are user-friendly and common; many hospitals use various IV pump types (including syringe pumps).
    • Training is provided on whichever pump is used at your hospital during orientation.
    • Alaris pumps can manage up to five different intravenous fluids simultaneously; currently shown with two modules hooked up (A and B) but expandable to five modules.
    • Modules can be added from storeroom to reach up to five concurrent IV lines; most ICU use involves multiple modules, floor units typically use up to two per patient (one main IV fluid, one piggyback medication).
    • Piggybacks: secondary meds (e.g., antibiotics) delivered via piggyback lines. Pumps can be programmed to run at a set rate and automatically revert to the main fluid once the piggyback completes.
    • Benefits: precise infusion rates, reduces fluid overload risk, alarms alert if there is a line problem.
    • Practical advice: use pumps whenever available; some facilities may have limited pumps, but modern units increasingly have many.

  • Hands-on preparation and safety with IVs

    • You’ll practice priming and spiking a bag before touching a patient.
    • IV tubing includes a needleless access port; if needed, use a filter needle to draw medication from vial to avoid glass shards.
    • Vials and reconstitution: different vial types include powder-to-diluent, liquids, and pre-mixed products; procedures vary by product type.

  • Vials, ports, and reconstitution examples

    • Needleless ports on IV tubing require proper access before injecting meds via the port.
    • Simple IV piggyback example: an antibiotic or other med can be piggybacked into the main IV line; when done, the pump can switch back to the main fluid automatically.
    • Some drugs come as a powder that must be reconstituted by injecting diluent, mixing, and then reinfusing; shaking is generally discouraged; roll gently to mix.
    • When opening vials, clean the top with an alcohol prep and use a Filter Needle to draw from vials with glass tops to prevent shards from entering the syringe.
    • Many vials have protective caps not guaranteed to be sterile; always clean the top with an alcohol prep before sticking a needle.

  • Medication forms and routes (parenteral medications)

    • Injectable meds include analgesics, chemo drugs, antibiotics, antifungals, steroids (e.g., Solu-Medrol), immunoglobulins, blood products, IV fluids, etc.
    • Ointments and salves (e.g., bacitracin, Neosporin) may be used for wounds.
    • Patches: require site cleaning with an alcohol prep before applying; remove the old patch first and clean the area; rotate sites (do not apply to the same site twice in one day).
    • Hair considerations: shaving can cause micro-abrasions and infection risk; prefer clipping with disposable razor heads and avoid shaving close to the skin.
    • Rectal meds: some meds can be given rectally (laxatives, anti-inflammatories, antiemetics, certain pain meds); always use the correct route and documentation.

  • Documentation and safety culture

    • Always document medications; do not document on behalf of someone else.
    • In emergencies (codes), the code sheet serves as a temporary documentation interface, with signatures confirming accuracy.
    • Dosing must be precise and patient-specific (weight-based dosing in pediatrics; adults use standard weights).
    • Interruptions during medication administration should be minimized to prevent errors.

  • Pyxis/Omnicell medication dispensing system

    • Pyxis looks like an ATM for meds; you log in with credentials and access the patient’s medications.
    • After selecting meds for a time window (e.g., 09:00 meds), drawers and bins pop open and you collect meds, placing them into a ziplock bag labeled with the patient’s label.
    • Meds are scanned and verified against the patient’s order before administration; you carry only that patient’s meds in your pocket and leave others secured until you reach their room.
    • After administration, you log out and move to the next patient; the process is designed to ensure patient-specific verification.
    • Narcotics handling: Pyxis tracks counts; counts are performed at the start and end of each shift by the outgoing and incoming charge nurses; you must reconcile any discrepancies before anyone can leave.
    • If a controlled substance is running low, an RN (often the charge nurse) must request stock from pharmacy using a formal form and count sheet; stockers at pharmacy replenish par levels and check for expiration.
    • Pharmacy collaboration and checks: stockers maintain par levels, rotate stock, and remove expired meds; multiple checks and balances exist between unit and pharmacy.

  • Break to introduce metric system concepts (foundation for dosing math)

    • The metric system is base-1000 for prefixes; base units include grams (mass) and liters (volume).
    • Prefixes commonly used in healthcare:
    • kilo- = 1000 × base
    • deci- = 0.1 × base (rarely used in healthcare)
    • centi- = 0.01 × base
    • milli- = 0.001 × base
    • micro- = 0.000001 × base
    • For length, centimeters are used (1 m = 100 cm).
    • Base units and relationships:
    • 1\,\text{kg} = 1000\,\text{g}
    • 1\,\text{g} = 1000\,\text{mg}
    • 1\,\text{mg} = 1000\,\mu\text{g}
    • Common healthcare weight/volume units:
    • Weight: kilograms (kg), grams (g), milligrams (mg), micrograms (µg)
    • Volume: liters (L), milliliters (mL), cubic centimeters (cc) which are equivalent to mL
    • Length: centimeters (cm)
    • Volume basics: 1 cc = 1 mL
    • Temperature scales in healthcare: Celsius is standard; Fahrenheit is commonly displayed on machines but converted automatically by equipment

  • Metric, temperature, and conversion references you’ll use

    • Volume conversions seen in practice:
    • 1 teaspoon = 5 mL
    • 1 tablespoon = 3 teaspoons = 15 mL
    • 1 ounce = 30 mL
    • 1 cup = 8 oz = 240 mL
    • Ice chips rule (volume): 4 oz of ice chips equals 120 mL when melted (not ice cream, not sherbet) due to volume displacement and melting behavior.
    • Weight conversions between pounds and kilograms:
    • \text{kg} = \frac{\text{lb}}{2.2}
    • \text{lb} = 2.2 \text{ kg}
    • Temperature benchmarks:
    • Normal body temperature roughly 37^{\circ}\text{C} = 98.6^{\circ}\text{F}
    • Freezing: 0^{\circ}\text{C} = 32^{\circ}\text{F}
    • Conversion formulas (handy, though many devices automate):
      • F = \frac{9}{5} C + 32
      • C = \frac{5}{9} (F - 32)

  • Intake and Output (I&O) and monitoring basics

    • INO (intake and output) tracking is used for certain patients (e.g., cardiac patients, diuretic therapy).
    • Typical tracking methods:
    • Intake: fluids swallowed or administered (oral, IV fluids, ice chips counted by volume, etc.).
    • Output: urine, emesis, stool, drainage from drains, and any liquid losses.
    • Urology tools: hat (for women) and urinal (for men) to measure urine; urimeter attached to bags for precise hourly measurements.
    • Example intake/output scenario:
    • Intake: 1 cup water (240 mL) + 240 mL Jell-O + 120 mL ice cream (volume for volume) + 1000 mL IV fluid = total intake 1600 mL.
    • Output: 500 mL urine + 350 mL urine + 600 mL urine + 50 mL emesis = total output 1500 mL.
    • General rule: intake is typically greater than output; if output exceeds intake, patient may be dehydrated or diuretic use may be in effect.
    • Minimum urine output benchmark: no patient should have less than about 30 \text{ mL/hour} ; persistent <30 mL/h may indicate kidney issues.
    • If urine output is too low, consider catheterization for precise measurement; some bags include a urimeter for hourly accuracy.

  • Pain assessment and pediatric considerations

    • Pediatric pain scales: Wong-Baker scale on badges; visual cues (grimacing, muscle tension) help when self-reporting is not possible.
    • Neonatal pain assessment: NIPS (neonatal infant pain scale) uses observed behavior and posture to gauge pain.
    • Elderly dosing: go low and go slow due to altered metabolism, liver/kidney function, and risk of confusion (sundowning).
    • Real-world caution: examples show risk of oversedation in elderly when dosing is not carefully tailored.

  • Dosage calculation rules and rounding conventions (core study notes)

    • Dosage calculation formula (basic):
    • \text{Dose} = \frac{\text{Desired}}{\text{Available}} \times \text{Quantity}
    • Some teaching uses the equivalent form: \text{Dose} = \frac{\text{Desired}}{\text{Available}} \times \text{Quantity} (same concept; ensure correct interpretation of each term).
    • Important practice rules
    • Always read the order carefully.
    • Double-check calculations; use a calculator; ask a colleague to verify if needed.
    • Do not round intermediate results; round only the final answer.
    • When conversions are involved (e.g., weight-based dosing), keep full precision until final step.
    • Rounding guidelines
    • For liquids (injections or oral) with > 1 mL: round to the nearest tenth (0.1).
    • For liquids with < 1 mL: round to the nearest hundredth (0.01).
    • Pediatric dosing often requires hundredths due to precise dosing needs.
    • Administration specifics
    • Capsules should be given whole; do not open capsules.
    • Some tablets are scored and can be split (e.g., 0.5 tablet); non-scored tablets should not be split.
    • For fractions in prescriptions, use a leading zero: 0.5 mg rather than .5 mg.
    • If the dose is a whole number, do not add trailing zeros (e.g., 5 mg, not 5.0 mg).
    • Special note on fractions and multiples
    • Example: If a doctor orders 500 mg and you have 250 mg tablets, you need:
      • \frac{500}{250} \times 1 = 2 tablets.
    • If you have 400 mg order and 200 mg tablets: \frac{400}{200} \times 1 = 2 tablets.
    • If you have 25 mg and 50 mg tablets (unscored): \frac{25}{50} \times 1 = 0.5 tablet.
    • If you have 500 mg and a solution that is 250 mg per 5 mL: \frac{500}{250} \times 5\ \text{mL} = 2 \times 5\ \text{mL} = 10\ \text{mL}.
    • Dimensional analysis (conversion factor) briefly mentioned
    • If needed, use dimensional analysis to convert between units; practice problems and resources are available for further study.

  • Practical reminders and incident-prevention tips

    • Do not interrupt medication administration; dedicated focus improves safety.
    • When stocking Pyxis, ensure counts and par levels are maintained to prevent stockouts and expiration.
    • If you suspect a discrepancy (e.g., a missing narcotic), do not approximate—investigate and reconcile before leaving the unit.
    • Involve pharmacy for replenishment of controlled substances and to handle non-standard or new products with in-service training when introduced.
    • Documentation and patient safety culture are foundational: accurate charting, appropriate route/form, and precise dosing are non-negotiable.

  • Quick reference aids and memory tricks from the session

    • Visual aid for metric prefixes using your hand: each finger segment equals 5 mL (teaspoon); collectively, a finger is 15 mL (tablespoon); two tablespoons equal 1 ounce (30 mL).
    • A practical reminder slide on metric temperature conversions and everyday equivalents (e.g., 1 cc = 1 mL).
    • The nurse’s rule of thumb: go slow with elderly dosing, monitor closely, and adjust based on renal/hepatic function and patient response.

  • Summary takeaways

    • IV pumps improve accuracy and safety; know how to prime, spike, and program them, and understand the piggyback concept versus main line dosing.
    • Mastery of vial opening, using filter needles, and proper dilution/reconstitution is essential for safe parenteral meds.
    • Pyxis/Omnicell is central to safe, traceable medication dispensing; always verify with patient-specific orders and proper scanning.
    • Be proficient with the metric system basics, especially for dose calculations, conversions (kg, g, mg, mL, mL), and temperature conversions; memorize common factors and typical patient scenarios.
    • Dosage calculations require careful reading, correct formulas, precise rounding, and clear documentation; always double-check and seek help if needed.

  • Quick practice prompts (remember the rules and formulas)

    • Basic dosage: if the order is 500 mg and you have 250 mg tablets, how many tablets are needed? Answer: \frac{500}{250} \times 1 = 2 tablets.
    • If the order is 25 mg and tablets are 50 mg, how many tablets? Answer: \frac{25}{50} \times 1 = 0.5 tablet (half-tablet, if scored).
    • If the order is 500 mg and you have 250 mg tablets with 5 mL per tablet, how many mL are needed? Answer: \frac{500}{250} \times 5 = 10 \text{ mL}.

  • End note

    • Practice problems and more detailed worked examples are available; use them to reinforce the rules and ensure accuracy in real clinical settings.