Written by: Wafa Shwaiky. RPH
¨ Type of Drug Distribution Systems.
B- Unit Dose Drug System (UD).
§ Physician’s Drug Order.
§ Intravenous Admixture Services.
§ Labeling and Dispensing.
§ Medication’s Delivery
§ Types of UDS.
§ Advantages of UDS
One of the primary responsibilities of the hospital pharmacy practitioners is to have the proper drug in the proper form and strength available at the appropriate time, to the patient. Although this sounds relatively simple, the system required to perform this task is complex and involves considerable organization.
The design of a medication distribution system requires an in-depth examination of activities with an obligation to efficiency, economy, and safety pursuant to the distribution of medications. The sequence of events involved in medication distribution conceptually begins when the drug is purchased from it’s source and follows a logical pattern to the point of administration and patient monitoring of the consumed product.
The managerial aspects of a medication distribution system must interface with many pharmacy functions. It is difficult to remove purchasing, inventory control, pricing, receiving, storage, quality control, and similar functions from those involved in the actual distribution of medications to patients. On the other hand, the clinical aspects of a medication system extend beyond the distribution of a medication to a patient and include activities related to the action of medications on the patient.
Usually, when medication distribution is discussed, it is considered in terms of the mechanism used to move and/or store the drug relative to patient care areas. Thus, terms such as floor stock, unit dose, and the patient prescription systems have found common use. The medication distribution system must be concerned with all areas in the institution where drugs are used. Thus, not only must nursing units be considered, but the pharmacist must give consideration to the distribution and control of medications to other patient care areas such as the emergency room, operating room, and radiology department. A program of quality improvement and control must be provided to safeguard the distribution and control of drugs to all areas in the institution.
Types of Distribution Systems
A- Traditional Systems
1- Floor or Ward Stock System: In this system, all but the most unusual drug items are stocked on the nursing stations in all patient care areas. Drug products which require especially strict control are often omitted from floor stock, such drugs are sent to the nursing unit upon receipt of a prescription order for the individual patient.
1- Ready availability of most drugs to the nurses and physicians assigned to the nursing station.
2- Fewer inpatient prescription orders.
3- Minimized return of medication.
4- reduced pharmacy personnel requirements.
1. Increased potential for medication errors resulting from lack of review by the pharmacist of each individual patient medication order.
2. Financial loss due to misappropriation of medication by hospital personnel and the administration of medication to patients without initiating charges.
3. Increased drug inventory in the institution.
4. Increased cost of loss due to obsolescence and deterioration.
5. Limited capacity for proper storage facilities on the nursing units in many hospitals.
6. Increased danger of unnoticed drug deterioration jeopardizing patient safety.
7. Consumption of nursing manpower in the preparation of medication doses and in conducting other medication-related activities.
2- Individual Prescription Order System: In this system, virtually all medications are dispensed by the pharmacist on individual prescription orders. While not as disadvantageous as the complete floor stock system, this method is also discouraged.
Some of the disadvantages include:
1. increased potential for medication errors due to the lack of checks in the distribution of medication doses and to the inefficiencies inherent in the procedures used to schedule, prepare, administer, control, and record during the drug distribution and administration process.
2. Consumption of excessive nursing manpower in the preparation of medication doses and in conducting other medication-related activities.
3. Increased potential for drug loss due to waste, obsolescence, and deterioration.
3- Combination of the above mentioned systems:
This is the most common method of medication distribution. In this system most drugs are dispensed on an individual prescription basis. The remaining drugs are obtained via limited floor stock. Included in the drugs found on floor stock are those that are frequently used, and comprise analgesic controlled substances, non-prescription medication like Paracetamol (Acetaminophen) , pre-operative anesthetic agents, and others not suited for individual prescription orders.
In this system nursing personnel spend a great amount of time preparing individual doses, reconstituting injectable medications, and ordering floor stock.
This system lacks adequate checks of the dosages prepared and the accuracy of charting of medication administration is often less than desirable.
B- Unit Dose System (UD).
Historical review: In the early 1960s of the last century, it became apparent that more sophisticated distribution systems would be required. During this period, UDs as a new drug distribution system, was introduced.
Several university hospitals in USA were, in part, responsible for laying the foundation and providing the impetus for shifting to UD.
Several shortcomings in the old distribution systems became obvious during the evolution to unit dose, which are:
§ Underutilization of pharmacists.
§ Inefficient use of nursing personnel.
§ Expanded inventory.
§ Deficiencies in interpretation and transcription of physicians' orders resulting from lack of review by a pharmacist.
§ Appearance of high incidence of medication errors in hospitals in the literature.
These shortcomings, if not overcome, appear much improved by unit dose distribution.
UDS and cost: It is possible that the potential increased initial costs has been one of the more common considerations impeding the acceptance of the UDS. One must, however, probe deeper into the concept of UD than merely glancing at the higher initial costs. There are ways in which a UDS can realize a savings instead of an added cost. For example, one hospital of 413 beds projected a savings of $21,000 per year by recovering 14.5 nursing hours per day as a result of UD.
Another study showed that nursing time spent in medication-related activities decreased by 45% in a UDS.
Another revealed that the UDS when compared with a traditional systems can:
1- Decrease nursing costs by $0.50 per patient per day.
2- Increase pharmacy personnel costs by $0.31 per patient per day.
3- Increase Equipment expenditures by $0.02 per patient per day.
4- Decrease the total hospital drug budget by $0.05 per patient per day.
5- Perform other savings a result of increased drug control, less pilferage, and less wastage of medications.
Many other hospitals have reported savings as a result of the UDS implementation.
Admittedly, the initial costs of the UDS are higher than the initial costs of traditional drug distribution systems. However, the life cycle costs of the UDS considering nursing time saved, increased efficient drug control, and decreased pilferage and wastage are less than those of traditional types of drug distribution systems.
UDS and medication errors: An equally important facet of the UDS is the belief that the utilization of such a system would reduce medication errors. A failure in the medication delivery system of a hospital may result in a medication error. If so, then one could substitute “medication system failure" with "medication error."
Studies have compared the error rates before and after the installation of unit dose drug distribution systems.
UDS and personnel acceptance: Regardless of the savings of a system in time, money, or errors, the success or failure of a system depends upon the personnel directly responsible for its operation. If unfavorable attitudes or a lack of interest are directed at the system, then in all likelihood its operation will be somewhat less than optimal. Because of the importance of this component, studies regarding attitudes toward the UDS have been conducted.
A survey undertaken at the University of Iowa after the installation of a UDS revealed a favorable response from nursing towards the new system. A majority of nurses felt the new system allowed increased time for direct patient care and improvement in the overall quality of patient care. Medical residents and interns indicated positive attitudes toward increased consultation with pharmacy personnel. Pharmacists, themselves, noted an increased utilization of their professional training under the unit dose system. Generally, all professional groups surveyed were favorable to the unit dose system over the traditional system. Similar results were obtained in a survey conducted at the University of Kentucky Hospital after installation of a unit dose system.
Unit Dose System (UDS): is a pharmacy-coordinated method of dispensing and controlling medication in organized health-care settings.
Although the UDS may differ in form, depending on the specific needs resources, and characteristics of each institution, four elements are common to all
- Medications are contained in, and administered from, single unit or unit dose packages.
- Medications are dispensed in ready-to-administer form to the extent possible.
- For most medications, not more than a 24-hour supply of doses is provided to or available at the patient-care area at any time.
- A patient medication profile is concurrently maintained in the pharmacy for each patient.
Floor stocks of drugs are minimized and limited to drugs for emergency use and routinely used “safe” items such as mouthwash and antiseptic solutions
Unit dosed tablets and capsules
Unit Dose (UD) Package: is a package that contains the ordered amount of a drug in a dosage form ready for administration to a particular patient by the prescribed route at a prescribed time. (e.g., the physician ordered 500mg Ampicillin the UD package can be one single-unit package of 500mg capsule or tow single-unit packages of 250mg capsules).
Single-Unit Package is one which contains one discrete pharmaceutical dosage form,( e.g., one tablet, one capsule, or one 30-m1 liquid quantity).
Inhalation UD package
Patient Medication Profile: is An essential item that must be maintained in the pharmacy for all inpatients and those outpatients routinely receiving care at the institution, and updated continuously.
The patient medication profile may be a written copy or computer maintained. It must be reviewed by the pharmacist before dispensing the patient’s drug(s), and it serves many purposes such as:
1- Enables the pharmacist to become familiar with the patient’s total drug regimen, enabling him to detect quickly potential interactions, unintended dosage changes, drug duplications and overlapping therapies, and drugs contraindicated because of patient allergies or other reasons.
2- it is required in UDS in order for the individual medication doses to be scheduled, prepared, distributed, and administered on a timely basis.
3- It may be useful for retrospective drug use review studies
Patient profile format may vary from one hospital to another, it should include the following information:
• Patient’s full name, date hospitalized, age, sex, weight, hospital I.D. number, and provisional diagnosis or reason for admission.
• Laboratory test results.
• Other medical data relevant to the patient’s drug therapy.
• Sensitivities, allergies, and other significant contraindications.
• Drug products dispensed , dates of original orders, strengths, dosage forms, quantities, dosage frequency or directions, and automatic stop dates.
• Intravenous therapy data (this information may be kept on a separate profile form, but there should be a method for the pharmacist to review both concomitantly).
• Blood products administered.
• Initials of the Pharmacist or technician tanscribing and verifying (checking) the transcription of the medication order.
• Number of doses or amounts dispensed.
• Items relevant or related to the patient’s drug therapy (e.g., blood products) not provided by the pharmacy.
Physician’s Medication Order:
A- Medication orders should be written legibly in ink and should include:
• Patient’s name and location (ward, room No, and bed No) .
• Medication Generic Name.
• Dosage, frequency and route of administration.
• Signature of the physician.
• Date and hour the order was written.
B- Any abbreviations used in medication orders should be agreed to and jointly adopted by the medical, nursing, pharmacy, and medical records staff of the institution. Lately, in the interest of patient safety,” Do Not Abbreviate” is the new practice nowadays.
C- Before dispensing the drug The pharmacist must receive the physician’s original order or a direct copy of the order (except in emergency situations). This permits the pharmacist to:
· Resolve questions or problems with drug orders before the drug is dispensed and administered.
· Eliminate errors which may arise when drug orders are transcribed into another form for use by the pharmacy.
Methods of sending the Physician’s orders to the pharmacy are:
1. Self-copying order forms: This method provides the pharmacist with a duplicate copy of the order and does not require special equipment. There are two basic formats:
a. Orders for medications included among treatment orders.
b. Medication orders separated from other treatment orders on the order form.
2. Electromechanical: Copying machines or similar devices may be used to produce an exact copy of the physician’s order. Provision should be made to transmit physicians’ orders to the pharmacy in the event of mechanical failure.
3. Computerized: Computer systems, in which the physician enters orders into a computer which then stores and prints out the orders in the pharmacy or elsewhere.
Medications should be dispensed only on the written order of a qualified physician or other authorized prescriber. Allowable exceptions to this rule (i.e., telephone or verbal orders) should be put in written form immediately and the prescriber should countersign the nurse’s or pharmacist’s signed record of these orders within 48 (preferably 24) hours. Only a pharmacist or registered nurse should accept such orders. Provision should be made to place physician’s orders in the patient’s chart, and a method for sending this information to the pharmacy should be developed.
D- Any questions arising from a medication order, including the interpretation of an illegible order, should be referred to the ordering physician by the pharmacist. It is desirable for the pharmacist to make (appropriate) entries in the patient’s medical chart pertinent to the patient’s drug therapy. Also, a duplicate record of the entry can be maintained in the pharmacy profile.
E- Order’s Time limits and changes: Medication orders should be reviewed automatically when the patient goes to the delivery room, operating room, or a different service. In addition, a method to protect patients from indefinite, open-ended drug orders must be provided. This may be accomplished through one or more of the following:
- Routine monitoring of patients’ drug therapy by a pharmacist;
- Drug class-specific, automatic stop order policies covering those drug orders not specifying a number of doses or duration of therapy;
- Automatic cancellation of all drug orders after a predetermined (by the P&T committee) time interval unless rewritten by the prescriber.
Whatever the method used, it must protect the patient, as well as provide for a timely notification (48 hours) to the prescriber that the order will be stopped before such action takes place.
F- Before the drug is entered into the dispensing system the pharmacist must review and interpret every medication order and resolve any problems or uncertainties. He must be satisfied that each questionable medication order is, in fact, acceptable. This may occur through:
· Study of the patient’s medical record.
· Research of the professional literature.
· Discussion with the prescriber or other medical, nursing, or pharmacy staff.
It is generally advisable for the pharmacist to document actions relative to a questionable medication order on the pharmacy’s patient medication profile form or other pharmacy document.
Once the order has been approved, it is entered into the patient’s medication profile.
G- Special orders such as stat, emergency, non-formulary drugs, investigational drugs, restricted use drugs, or controlled substances, should be processed according to specific written procedures meeting all applicable regulations and requirements.
H- A schedule of standard drug administration times must be developed by the pharmacy, nursing, and medical staffs, through the P&T committee. The nurse should notify the pharmacist whenever it is necessary to deviate from the standard medication schedule.
I- A mechanism to continually inform the pharmacy of patient admissions, discharges, and transfers should be established.
Intravenous Admixture Services:
The pharmacy is responsible for assuring that all sterile products used in the institution are:
1- Therapeutically and pharmaceutically appropriate to the patient.
2- Free from microbial and pyrogenic contaminants.
3- Free from unacceptable levels of particulate and other toxic contaminants.
4- Correctly prepared.
5- Properly labeled, stored, and distributed.
Centralizing all sterile compounding procedures within the pharmacy department is the best way to achieve the above mentioned goals.
For more details concerning Parenteral admixtures please click here.
Labeling and Dispensing:
The pharmacist is responsible for labeling medication containers. Labels and medication containers should be characterized as follow:
- Medication labels should be typed or machine printed.
- Labeling with pen or pencil and the use of adhesive tape or china marking pencils should be prohibited.
- A label should not be superimposed on another label.
- The label should be legible and free from erasures and strikeovers.
- The label should be firmly affixed to the container
- The label for stock containers should be protected from chemical action or abrasion and bear the name, address, and telephone number of the hospital.
- Medication containers and labels should not be altered by anyone other than pharmacy personnel.
- Prescription labels should not be distributed outside the pharmacy.
- Instruction labels and statements (shake well, may not be refilled, refrigerate, etc..) should be used as required.
- Any container to be used outside the institution should bear its name, address, and phone number.
- Important labeling considerations are:
1- The metric system should be given prominence on all labels when both metric and apothecary measurement units are given.
2- The names of all therapeutically active ingredients should be indicated in compound mixtures.
3- Labels for medications should indicate the total amount of drugs.
4- Drugs and chemicals in forms intended for dilution or reconstitution should carry appropriate directions.
5- The expiration date of the contents, as well as proper storage conditions, should be clearly indicated.
6- For parenteral medications, route of administration should be indicated.
7- Labels for large volume sterile solutions should permit visual inspection of the container contents.
8- Numbers, letters, unofficial synonyms, and abbreviations should not be used to identify medications, with the exception of approved letter or number codes for investigational drugs, or drugs being used in blinded clinical studies.
9- Containers presenting difficulty in labeling, such as small tubes should be labeled with no less than the prescription serial number, name of drug, strength, and name of the patient. The container should then be placed in a larger carton bearing a label with all necessary information.
10- The label should conform to all applicable local laws and regulations.
11- Medication labels of stock containers and repackaged or prepackaged drugs should carry codes to identify the source and lot number of medication.
12- Drug strengths, volumes, and Amount dispensed should be indicated.
Small containers & Syringes labeling
· Couriers used to deliver medications should be reliable and carefully chosen.
· Pneumatic tubes, dumbwaiters, medication carts, and the like should protect drug products from breakage and theft.
Medication carts Pneumatic tubes
Another kind of Pneumatic tubes
· In those institutions having automatic delivery equipment, such as a pneumatic tube system, provision must be made for an alternative delivery method in case of breakdown.
· All parts of the transportation system must protect medications from pilferage. Locks and other security devices should be used where necessary.
· Procedures for the orderly transfer of medications to the nurse should be instituted; i.e., drug carts or pneumatic tube carriers should not arrive at the patient-care area without the nurse or her designee acknowledging their arrival.
· Medications must always be properly secured.
· Storage areas and equipment should meet the Hospital Drug Distribution and Control requirements.
Most UDSs are designed to deliver medications on a scheduled basis, i.e., one, two, three, or four times daily. At least one computerized program is designed to deliver medication on an hourly basis. The more frequent the delivery cycle, the more controls found in the medications distribution system.
Some hospitals have found it advantageous to include drug administration as a part of the medication distribution system. One primary objective of a pharmacy controlled medication administration system is to provide for the safe and accurate use of medications from the time the orders are written to the time the medications are administered to the patients.
Types of UDS:
There are three major types of UDS:
1. Centralized UD Program: Drugs are dispensed from the central pharmacy to the inpatient ward, this system is applicable in small health institute.
2. Decentralized UDS: The doses are prepared in two or more "satellite" pharmacies located in or near the patient care areas of the hospital:
3. A combination of the two systems: this utilizes one of two approaches:
a. The pharmacists are decentralized while the doses are prepared in a central location.
b. Satellite pharmacies are operated for limited periods of time (a centralized program exists during the time the satellite pharmacies are not open).
The logistics associated with a particular hospital environment may be the primary determinant in choosing whether or not a centralized or decentralized system will be utilized.
A centralized UD program allows for somewhat greater management efficiency and control, while the decentralized program provides for a closer pharmacist-physician-patient-nurse relationship.
Whether or not a UD program is centralized, decentralized, or a combination system has little effect upon the mechanics and procedures utilized. The components common to all UD systems are:
1. A method whereby medication orders can be delivered to pharmacy (i.e., pneumatic tube, courier, dumbwaiter, etc.)
2. A patient profile which can be used as a document to fill doses and, if necessary, as a charge document.
3. Medication drawers in a cart or cassette for holding patient medications.
4. A mechanism for delivering the medication drawers (i.e., transportation cart, utility cart, exchange of medication carts, etc.)
5. A system whereby the drugs are available at the patient's room at the appropriate time for administration.
6. A system designed to document administration of the drug.
7. A system to package oral solids, oral liquids, and injectable products.
Advantages of UDS:
Numerous studies concerning UDS have been published over the past several decades. These studies indicate categorically that UDSs, with respect to other drug distribution methods, are:
1- Safer for the patient.
2- More efficient and economical for the organization.
3- A more effective method of utilizing professional resources
More specifically, the inherent advantages of UDSs over alternative distribution procedures are:
1- A reduction in the incidence of medication errors.
2- A decrease in the total cost of medication-related activities.
3- A more efficient usage of pharmacy and nursing personnel allowing for more direct patient-care involvement by pharmacists and nurses.
4- Improved overall drug control and drug use monitoring.
5- More accurate patient billings for drugs.
6- The elimination or minimization of drug credits.
7- Greater control by the pharmacist over pharmacy workload patterns and staff scheduling.
8- A reduction in the size of drug inventories located in patient-care areas.
9- Greater adaptability to computerized and automated procedures.
In view of these demonstrated benefits, the American Society of Health systems Pharmacists ASHP considers the UDS to be an essential part of drug distribution and control in organized health-care settings in which drug therapy is an integral component of health-care delivery.
1- Mickey C. smith,Ph.D, Thomas R. Brown, Pharm.D, “ Handbook Of Institutional Pharmacy Practice”, Copyright 1979.
2- American Society of Health-System Pharmacists, “Best Practices for Hospitals & Health- System Pharmacy”, 2005-2006 Edition.