Pharmacy Practice Chapter 13

Small Volume Parenterals (SVPs)

Volume Capacity: 100 mL or less

Primary Preparation Type: Intravenous Piggybacks (IVPBs)

Administration Duration: Intermittent (15 to 60 minutes)

Clinical Indication: Intermittent medication delivery (e.g., antibiotics)

Large Volume Parenterals (LVPs)

Volume Capacity: 250 mL, 500 mL, or 1,000 mL

Primary Preparation Type: Continuous infusions, TPNs, Maintenance fluids

Administration Duration: Continuous (8 to 24 hours)

Clinical Indication: Fluid replenishment, electrolyte delivery, nutrition

Isotonic IV Solutions

Exert the same osmotic pressure as red blood cells and human plasma (~290 mOsm/L), preventing net fluid shifts into or out of cells.

Standard Isotonic Solutions

0.9% Sodium Chloride (Normal Saline / NS) and Lactated Ringer's (LR).

Hypotonic Solutions

0.45% NaCl (Half-Normal Saline) causes cells to swell.

Hypertonic Solutions

3% NaCl, 10% Dextrose (D10W) cause cells to shrink.

pH Value

Represents the log concentration of hydrogen ions, indicating solution acidity or alkalinity on a scale from 0 (acidic) to 14 (basic/alkaline), with 7 being neutral.

Why must parenteral solutions remain within safe pH limits?

To avoid vascular damage, tissue phlebitis, or chemical instability.

Automated Compounding Devices (ACDs)

Computer-controlled high-precision fluid transfer systems are used primarily to prepare complex multi-ingredient Total Parenteral Nutrition (TPN) bags.

Automated Compounding Devices (ACDs) are primarily used for:

Preparing complex multi-ingredient Total Parenteral Nutrition (TPN) bags.

Filter Needles One-Directional Design

A filter needle must be used in one direction only (e.g., drawing fluid out of an ampule into the syringe).

Filter Needles Handling Rules

Never swab a filter needle membrane with alcohol, as alcohol alters membrane surface tension and integrity.

Light-Sensitive Drug Protection

Must be enclosed in amber-colored protective covers or opaque light shields immediately following compounding

USP

Personal Protective Equipment (PPE)

Receiving HD Shipments

Personnel receiving HD packages must wear chemotherapy-tested gloves

HD Shipment Storage Environment

HDs must be stored separately from non-hazardous drugs in externally ventilated, negative-pressure storage areas with distinct labeled storage bins.

PPE Removal (Doffing)

Used PPE must be removed inside or immediately prior to exiting the HD preparation/buffer area to avoid transporting hazardous residues into non-hazardous workspace zones.

Chemotherapy Compounding Mats

Absorb droplets and minor spills

Hazardous Spill Management

When wiping liquid HD spills, clean-up operations must proceed from the outer perimeter inward toward the center

Safety Data Sheets (SDS)

Standardized documents provide detailed safety data on chemical composition, health hazards, protective measures, and immediate exposure response protocols. SDS must be readily accessible to all staff at all times.

Nuclear Pharmacy Practice

Radioactive pharmaceuticals (radiopharmaceuticals)

USP (United States Pharmacopeia)

Establishes enforceable national quality standards for pharmacy practice, including USP

NRC (Nuclear Regulatory Commission)

Federal agency tasked with regulating nuclear materials, atomic energy safety, and licensing facilities handling radioisotopes.

FDA (Food and Drug Administration)

Regulates drug manufacturing, approval, and cGMP compliance.

CDC (Centers for Disease Control and Prevention)

Sets national infection control guidelines and disease prevention standards.

Sterile Compounding Calculations: Flow Rate (mL/hr)

Flow Rate (mL/hr) = Total Volume (mL) / Total Time (hr)

Sterile Compounding Calculations: Infusion Duration (Hours)

Duration (hr) = Total Volume (mL) / Flow Rate (mL/hr)

Sterile Compounding Calculations: Drip Rate (gtt/min)

Drip Rate (gtt/min) = [Total Volume (mL) x Drop Factor (gtt/mL)] / Total Time (minutes)

Sterile Compounding Calculations: Dose Infusion Rate (mg/min)

Dose Rate (mg/min) = [Concentration (mg/mL) x Flow Rate (mL/hr)] / 60 min

Sterile Compounding Calculations: Alligation Grid Parts

High Part = |Desired % - Low %| ; Low Part = |High % - Desired %|

Practice Problem 1: Infusion Duration Calculation

Scenario: A patient is prescribed 750 mL of 0.9% NaCl solution running at an IV pump rate of 62.5 mL/hr. How many hours will this bag last?

Step 1: Identify given values: Total Volume = 750 mL; Rate = 62.5 mL/hr

Step 2: Apply formula: Hours = 750 mL / 62.5 mL/hr.

Result: 12 Hours

Practice Problem 2: Hourly Flow Rate (mL/hr)

Scenario A (Standard LVP): An order calls for 1,500 mL of D5NS to be infused over 10 hours. What rate in mL/hr should be programmed?

Calculation: Rate = 1,500 mL / 10 hours = 150 mL/hr.

Practice Problem 2: Hourly Flow Rate (mL/hr) PART 2

Scenario B (Intermittent IVPB): An antibiotic dose in a 150 mL volume is ordered to infuse over 45 minutes. What is the hourly rate setting?

Step 1: Convert minutes to hours: 45 min / 60 min/hr = 0.75 hours.

Step 2: Calculate rate: Rate = 150 mL / 0.75 hr = 200 mL/hr.

Practice Problem 3: Drip Rate Calculations (gtt/min)

Scenario A (Macrodrip Tubing): Infuse 600 mL of Lactated Ringer's over 5 hours using tubing with a drop factor of 15 gtt/mL.

Step 1: Convert time to minutes: 5 hours x 60 min/hr = 300 minutes.

Step 2: Calculate drip rate: (600 mL x 15 gtt/mL) / 300 min = 9,000 / 300 = 30 gtt/min.

Practice Problem 3: Drip Rate Calculations (gtt/min) PART 2

Scenario B (Microdrip Tubing): Infuse 120 mL over 1 hour using microdrip tubing ( drop factor = 60 gtt/mL).

Step 1: Convert time to minutes: 1 hour = 60 minutes.

Step 2: Calculate drip rate: (120 mL x 60 gtt/mL) / 60 min = 120 gtt/min.

Practice Problem 4: Dose Infusion Rate (mg/min)

Scenario: A bag containing 800 mg of dopamine in 250 mL D5W is infusing at 30 mL/hr. How many milligrams per minute are delivered?

Step 1: Concentration = 800 mg / 250 mL = 3.2 mg/mL.

Step 2: Hourly dose = 30 mL/hr x 3.2 mg/mL = 96 mg/hr.

Step 3: Minute dose = 96 mg/hr / 60 min/hr = 1.6 mg/min.

Practice Problem 5: Alligation Stock Preparation

Scenario: Prepare 400 mL of a 20% Dextrose solution using stock solutions of 50% Dextrose and 10% Dextrose.

Step 1: Alligation Grid Parts: Parts of 50% solution = |20 - 10| = 10 parts; Parts of 10% solution = |50 - 20| = 30 parts; Total Parts = 10 + 30 = 40 parts.

Step 2: Volume per part: 400 mL / 40 parts = 10 mL/part

Step 3: Component Volumes: Volume of 50% Dextrose = 10 parts x 10 mL/part = 100 mL; Volume of 10% Dextrose = 30 parts x 10 mL/part = 300 mL