Chapter 11

2. Chapter 11 Preparing Sterile Intravenous Products

3. Chapter 11 Topics • Intravenous Preparations • Equipment Used in IV Preparation • Preparing IVs • Calculations for the Hospital Pharmacy Technician

4. Learning Objectives • Describe the characteristics of intravenous solutions including solubility, osmolality, and pH • Identify common vehicles for intravenous solutions • Describe the equipment and procedures used in preparing parenterals • Identify the components of an intravenous administration set • Convert from Fahrenheit to Centigrade and vice versa • Calculate the molecular weight and milliequivalents of certain substances used in the pharmacy • Compute the specific gravity of liquids • Calculate intravenous rates and administration

5. Intravenous Preparations • The IV route of administration is used • to reach appropriate drug serum levels • to guarantee compliance • for drugs with unreliable gastrointestinal (GI) absorption • for the patient who can have nothing by mouth • for the patient who is unconscious or uncooperative, and for rapid correction of fluid or electrolytes • Most parenterals are introduced directly into the bloodstream • must be free of air bubbles or particulate matter • have many characteristics including solubility, osmolality, and pH

6. Characteristics of IV Preparations • Intravenous (IV) preparations are either: • solutions (in which ingredients are dissolved) • suspensions (in which ingredients are suspended) • Most parenteral preparations are made of ingredients in a sterile water medium • Some parenteral preparations may be oleaginous (oily)

7. Characteristics of IV Preparations • Parenteral IV preparations must have chemical properties that will not • damage vessels or blood cells • alter the chemical properties of the blood serum • With blood, IVs must be • iso-osmotic (having the same number of particles in solution per unit volume) • isotonic (have the same osmotic pressure, meaning the pressure produced by or associated with osmosis)

8. Characteristics of IV Preparations • Theosmolality is the amount of particulate per unit volume of a liquid preparation • measured in milliosmoles (mOsm) • osmolality of blood serum = 285 mOsm/L • An isotonic solution is a solution in which body cells can be bathed without a net flow of water across a semipermeable membrane • 0.9% normal saline (NS)

9. Characteristics of IV Preparations • Pharmacists sometimes must adjust tonicity of parenteral preparations to ensure they are near isotonic • A hypertonic solution has a greater number of particles than the blood cells themselves • 50% dextrose or 3% sodium chloride • A solution of less than normal tonicity is hypotonic, which has fewer numbers of particles than blood cells • 0.45% NS

10. Characteristics of IV Preparations • The pH value is the degree of acidity or alkalinity of a solution • acidic solution: pH of less than 7 • alkaline solution: pH value more than 7 • Human blood plasma has a pH of 7.4 • slightly alkaline • parenteral IV solutions should have a pH that is neutral (near 7)

11. Methods of Injection • The bolus, or injection, is one of the most common routes of IV administration • The injection is performed using a syringe • prepackaged in the form of filled, disposable plastic syringes • injectable drug must be taken up into the syringe from a single- or multi-dose glass or plastic vial, or from a glass ampule • Sometimes the solid drug in the vial has to be reconstituted by addition of a liquid before use

12. Methods of Injection • IV infusions deliver: • large amounts of liquid into the bloodstream over prolonged periods of time • IV infusion is used to deliver:

13. Discussion What are some characteristics of parenteral preparations, and why are they important?

14. Discussion What are some characteristics of parenteral preparations, and why are they important? Answer: Tonicity, osmolality, and pH are characteristics of parenteral preparations. It is important that they be adjusted to be as close as possible to the values for human blood, to prevent damage to blood cells and organs.

15. Terms to Remember • osmotic pressure • osmolality • isotonic solution • hypertonic solution • pH value

16. Equipment Used in IV Preparation • Pharmacies use plastic disposable products to • save time and money • provide the patient with an inexpensive sterile product • Often the entire system sent out to the patient floors is composed of plastic • thin, flexible plastic catheters are replacing metal shafts that deliver the medication into the vein • in many cases the only durable, nondisposable product used to deliver IV medication is the IV pump or controller

17. Commonly Used IV Abbreviations:Fluids

18. Commonly Used IV Abbreviations:Fluids

19. Commonly Used IV Abbreviations:Electrolytes

20. Commonly Used IV Abbreviations:Additives

21. Syringes and Needles • Syringes are used for IV push and in the preparation of infusions, are made of glass or plastic • Glass syringes are more expensive • use limited to medications that are absorbed by plastic • Plastic syringes • are less expensive • are disposable • come from the manufacturer sterile

22. Syringes and Needles • Needles are made of stainless steel or aluminum • needle lengths range from 3/8 of an inch to 6 inches • needles come in gauges ranging from 30 to 13 (higher the gauge, smaller the lumen) • After use, needles must be discarded in a designated sharps container

23. IV Sets • An IV administrationsetis a sterile, pyrogen-free disposable device used to deliver IV fluids to patients • The set may • be sterilized before use by means of radiation or ethylene oxide • come in sterile packaging and a sealed plastic wrap • Sets do not carry expiration dates • Sets carry the following legend: • “Federal law restricts this device to sale by or on the order of a physician.”

24. IV Sets • Nurses generally have the responsibility for • attaching IV tubing to the fluid container • establishing and maintaining flow rate • overall regulation of the system • Pharmacy personnel must assess aspects of IV systems, including infusion sets • A complete understanding of IV sets and their operation is important to pharmacists and pharmacy personnel

25. IV Sets • IV sets are sterile and nonpyrogenic • Each unit is supplied in packaging that ensures the maintenance of sterility • Flanges and other rigid parts of an IV set are molded from tough plastic • Most of the length of the tubing is molded from a pliable polyvinyl chloride (PVC) • PVC sets should not be used for • nitroglycerin, which is absorbed by the tubing • IV fat emulsions, which may leach out of the tubing

26. IV Sets Safety Note A damaged package cannot ensure sterility, even if all protectors are in place. It is best to discard sets that are found in unoriginal, opened, or damaged packages.

27. IV Sets Safety Note Do not use PVC IV sets for nitroglycerin or fat emulsions. Special types of plastic sets are required for such infusions.

28. IV Sets • The length of sets varies from 6-inch extensions up to 110- to 120-inch sets used in surgery • the priming of tubing depends on the length of the set • Standard sets have a lumen diameter of 0.28 cm • varying the size of the lumen diameter achieves different flow rates • regulation of flow rates is critical in neonates and infants

29. IV Sets • The tubing’s interior lumen may contain particles that flush out when fluid is run through the set • Use of final filtration has reduced the need for flushing the line with the IV fluid before attaching the set to the patient

30. IV Sets • A spike to pierce the rubber stopper or port on the IV container • A drip chamber for trapping air and adjusting flow rate • A control clamp for adjusting flow rate or shutting down the flow • Flexible tubing to convey the fluid

31. IV Sets • A needle adapter for attaching a needle or a catheter • A catheter, or tube, may be implanted into the patient and fixed with tape to avoid having to repuncture the patient each time an infusion is given

32. IV Sets • Most IV sets contain a Y-site, or injection port • a rigid piece of plastic with one arm terminating in a resealable port • used for adding medication to the IV • Some IV sets also contain resealable in-line filters • protection for the patient against particulates, including bacteria and emboli Go to www.baxter.com to see IV tubing products from a major manufacturer

33. IV Sets • The spike is a rigid, sharpened plastic piece used proximal to the IV fluid container • covered with a protective unit to maintain sterility • generally has a rigid area to grip while it is inserted into the IV container • If an air vent is present on a set, it is located below the spike • the air vent points downward and has a bacterial filter covering • the vent allows air to enter the bottle as fluid flows out of it • necessary for glass bottles without an air tube

34. IV Sets • The drip chamber is a transparent, hollow chamber located below the set’s spike • drops of fluid fall into the chamber from an opening at the uppermost end, closest to the spike • number of drops it takes to make 1 mL identifies an IV set

35. IV Sets • The most common IV drop sets are • 10 (10 gtt/mL) • 15 (15 gtt/mL) • 20 (20 gtt/mL) • 60 (60 gtt/mL) • An opening that provides 10, 15, or 20 gtt/mL is commonly used for adults • An opening that provides 60 gtt/mL is used for pediatric patients and is called a mini-drip set

36. IV Sets • The person administering the fluid starts the flow by filling the chamber with fluid from an attached inverted IV container • the chamber sides are squeezed and released • fluid flows into the chamber • procedure is repeated until an indicated level is reached or approximately half the chamber is filled • entering drops are counted for 15 seconds • adjustments made until approximate number of drops desired is obtained • rate should be checked five times, at 30-second intervals, and again for a last count of 1 minute

37. IV Sets • Clamps allow for adjusting the rate of the flow and for shutting down the flow • Clamps may be located at any position along the flexible tubing • Usually a clamp moves freely, allowing its location to be changed to one that is convenient for the health professional administering the medication

38. IV Sets • Types of clamps used for IV solutions include: • slide clamp: has an increasingly narrow channel that constricts IV tubing as it is pressed further into the narrowed area • screw clamp: consists of a thumbscrew that is tightened or loosened to speed or slow the flow • roller clamp: a small roller that is pushed along an incline • moving down the incline, constricts tubing and reduces fluid flow • moving up the incline, increases the flow

39. IV Sets • Clamp accuracy can be affected by: • creep: tendency of some clamps to return to a more open position with increased fluid flow • cold flow: tendency of PVC tubing to return to its previous position • The needle adapter • usually located at the distal end of the IV set, close to the patient • has a standard taper to fit all needles or catheters • is covered by a sterile cover before removal for connection

40. IV Sets • A set may have a built-in or in-line filter • Final filtration should protect the patient against particulate matter, bacteria, air emboli, and phlebitis • a 0.22-micron filter is optimal • a 5-micron filter removes particles that block pulmonary microcirculation but will not ensure sterility • AY-site is an injection port found on most sets • the Y is a rigid plastic piece with one arm terminating in a resealable port • the port, once disinfected with alcohol, is ready for the insertion of a needle and the injection of medication

41. Filters • Filters are devices used to remove contaminants such as glass, paint, fibers, and rubber cores • will not remove virus particles or toxins • will occasionally become clogged, thus slowing expected flow rates • Filter sizes include: • 5.0 microns – random path membrane (RPM) filter, removes large particulate matter • 0.45 microns – in-line filter for IV suspension drug • 0.22 microns – removes bacteria and produces a sterile solution

42. Catheters • IV administration for fluids and drug therapy can be accomplished through needle-like devices called catheters • Catheters are devices inserted into veins for direct access to the blood vascular system and are used in two primary ways: • peripheral venous catheters, which are inserted into a vein close to the surface of the skin • central venous catheters, which are inserted deeper in the body

43. Catheters • A peripheral venous catheter is inserted into veins close to the surface of the skin and used for up to 72 hours • unit is inserted into a vein • needle portion is withdrawn • flexible, Teflon catheter is left in place • Peripheral catheters are easy to insert, and most nurses can do this at a patient’s bedside • usually inserted in sites on the arms or hands • can be inserted in the feet and scalp if the nurse or physician cannot locate “good” veins in the arms or hands

44. Catheters • Peripheral venous catheters will likely cause problems 20 to 50% of patients • pain • irritation • infiltration • Infiltration is a breakdown or collapse of a vein that allows the drug to leak into tissues surrounding the catheter site, causing edema and/or tissue damage

45. Catheters • A central venous catheter is one placed deep into the body • more complicated to place • inserted by a physician to minimize the risk of infection • Central catheters are commonly used for therapy of 1 to 2 weeks or even longer • A central venous catheter is used to administer: • hypertonic solutions such as total parenteral nutrition (TPN) solutions • potentially toxic drugs such as cancer chemotherapeutic drugs

46. Catheters • The most common sites of insertion are • subclavian vein, lying below the clavicle and joining the jugular vein • jugular vein, in the neck • femoral vein, in the groin area • Placed deep in the vein so that the end enters the superior vena cava close to the heart where the blood flow is the greatest Visit the Web site of the American Society of Enteral and Parenteral Nutrition, a good source for information and networking

47. Catheters • Problems with subclavian catheters are: • possibility of subclavian vein laceration (i.e., missing the vein and puncturing a lung) • greater risk of infection because the procedure is more invasive • A larger blood flow in the subclavian vein will dilute a more concentrated solution such as TPN • TPN solutions provide • needed calories in the form of amino acids and dextrose • vitamins, minerals, trace elements, and electrolytes

48. Catheters • Amultiple-lumen catheter is used to separately administer potentially physically incompatible drugs • comes with one, two, three, or four lumens • Each lumen exits the catheter at a different location • no opportunity exists for the drugs to mix before being diluted in the bloodstream

49. Catheters • Midline catheters are longer peripheral catheters that go from insertion site into a deep vein • designed to stay in place 1 week or longer • The peripherally inserted central (PIC) line is a very fine line that is threaded through the peripheral vein into the subclavian vein • has the same characteristics as a central line • can be inserted by a skilled nurse at the bedside

50. Catheters • Some patients may be on TPN therapy for months or even years in the hospital or at home • Infusion devices are surgically implantedto: • provide long-term therapy • reduce the risk of infection