VS 202 CRI

Overview of Constant Rate Infusion (CRI)

Constant Rate Infusion (CRI) is an essential method of continuous medication administration, primarily through intravenous (IV) routes, which helps maintain stable plasma drug levels, providing consistent analgesia.

What is a CRI?

  • Continuous administration of medication to avoid "peaks and troughs" in plasma concentrations.

  • Often initiated with a loading dose to quickly reach therapeutic levels.

  • Followed by a continuous, smaller dose to maintain therapeutic effect.

Administration Method

  • CRI can be delivered via:

    • IV fluid bags with an IV pump.

    • Syringe drivers for more controlled delivery.

  • Careful calculation of dosages and fluid rates is critical to avoid breakthrough pain and potential side effects.

Intermittent Bolus vs. CRI

  • Intermittent Bolus:

    • Plasma concentration decreases continuously after reaching peak level.

    • Can lead to irregular drug effects and undesired side effects due to missed doses.

  • CRI:

    • Maintains therapeutic concentrations over time.

    • Minimizes peaks and avoids toxic reactions.

    • Supports multimodal analgesia and can spare MAC by up to 45%.

Indications for CRIs

  • Common uses include:

    • Analgesia/Sedation.

    • Electrolyte imbalances and GI support.

    • Inotropic support and medication supplementation.

Common Conversions

  • Weight: 2.2 lbs = 1 kg.

  • Medication: 1 g = 1000 mg; 1 mg = 1000 mcg.

  • Volume: 1 L = 1000 mL.

  • Concentration: 1% = 1 g/100 mL = 10 mg/mL.

Syringe Driver and IV Pumps

  • Syringe drivers are utilized for accurate dosing and control of infusion rates.

  • IV pumps offer precision in administration.

QS - Quantity Sufficient

  • Always remove fluid volume to maintain total volume in IV fluid bags for accurate calculations. Best practices include removing fluid before adding medications.

Calculating CRIs in IV Fluids

  • For example, dosing for a patient weighing 40.7 kg might include administration of Fentanyl, Lidocaine, and Ketamine at specified rates and concentrations. Accurate calculations of drug volumes are crucial for fluid administration.

Preparation of CRI

  • Employ aseptic technique during preparation:

    • Include labeling details: time, date, initials, drug name, volume in mg (mcg) and mL, carrier fluid volume, and rate/dose.

    • Use distinct, clear labels (often bright orange).

Monitoring Parameters

  • Essential monitoring includes:

    • Temperature, pulse, respiration, blood pressure, pain assessment, and blood evaluations.

    • Care for intravenous fluids and signs of adverse drug reactions must be regularly checked.

CRI Calculations

  • Emphasize the importance of labeling, double-checking work, practice in calculations, and knowing conversions for effective CRI management.