FUNCTIONAL REQUIREMENTS OF PhIS
The Pharmacy-Medication Information System (PhIS) integrates the distinct functions of the Pharmacy service with the medication functions carried out by nurses and doctors within the CIS-EMR. The functions are as elaborated below:
Functions of Medication and Pharmacy System
Pharmacy and Medication Applications and Functionalities
OBJECTIVES, POLICIES AND PROCESSES
The main objective of the medication function is to ensure that the correct medication with the correct dosage, quantity and frequency is supplied to the right patient. While the main role is played by pharmacy staff, sometimes clinicians (doctors or nurses) perform some of the functions. The processes involved in the medication function are:
- Plan treatment by medication (doctor)
- Prescribe drugs (doctor)
- Vet, verify and supply dugs (Pharmacist)
- Administer drugs (nurses, doctors, patient and home-carer)
Prescribing is performed by doctors from within CIS. It is not considered different from placing an order and therefore would use the order entry functionality. Vetting, verifying and supplying medication (to nurses or patients) is carried out by Pharmacists. Drug administration (by whatever route) is basically completing a task; the performance of which need to be charted in the Medication Administration Record (MAR).
It is the policy of most hospitals that clinicians prescribe only drug items available in the facility’s formulary. However, there is an allowance for a clinician to prescribe drugs approved by the Drug Control Authority (DCA) previously prescribed elsewhere by a registered medical practitioner and brought along by patients (patient’s own medication). Non-formulary items also include drugs approved for use in the particular hospital but not included in the hospital’s inventory. Therefore, for purposes of prescribing, the drug list needs to be divided into the hospital’s formulary and non-formulary items
DIFFERENCES FOR VARIOUS SERVICE DELIVERY SYSTEMS
There are three different service delivery systems as far as the supply and dispensing of medication is concerned i.e.:
- Outpatient medication
- Daily in-patient medication
- Medication for in-patients on discharge
Each system follows quite different work processes (discussed in later sections).
CLINICAL PHARMACY FUNCTIONS
Pharmacists may assume clinical functions as a member of the clinical team and are given clinical privileges. Their clinical functions would include:
- Take a drug history
- Perform an assessment on suitability of drugs intended to be prescribed based on clinical data (indications and contraindications)
- Review the effects of drugs provided to patients including effectiveness, toxicity, side-effects, interactions and allergies
- Record the occurrence of allergies and adverse effects of drugs
- Reconcile the drugs in use on a patient
- Prescribe drugs in certain instances when instructed by or as agreed by the doctor in charge.
- Provide patient education.
DRUG RECONCILIATION FUNCTION
For purposes of drug reconciliation doctors and pharmacists need to know all drugs the patient is taking or has taken. A unified view of data regarding drugs should be drawn from:
- Drug history
- Drugs prescribed
- Drugs supplied
- Drugs administered (Medication Administration Record)
- Drugs withheld or stopped
For in-patients, the Medication Administration Record (MAR) can be used to monitor the possibility of omission, duplication and interaction. Drug reconciliation is performed by changing orders i.e. reducing dosage, cancelling a prescription or ordering an alternate drug
The discharge medication can be reconciled by comparing the discharge medication prescription with the MAR and the drug history. For outpatients, whenever a patient is given a prescription a review is made of the patient’s previous medication to ensure that no required medication is left out. The patient should be asked whether he/she is getting medication from elsewhere steps taken to avoid duplication
The function of counselling is a clinical function and should use the CIS (using functionalities similar to that used in patient education function performed by nurses and counselling by medical social workers).
The vetting and validation process is discussed under decision support below. There are variations of the processes for in-patients and outpatients categories
It is expected that Pharmacists would use the OERR within the CIS to order these functions, when indicated, and create tasks and task lists. Data is entered and retrieved from the Patient Information Database. The CIS takes cognizance of these needs. There is no necessity for a separate application-software for the clinical function of Pharmacists nor should it be part of the PIS. However, there is a need for close integration between CIS-EMR and PhIS.
The Order Entry-Result Reporting System (OERRS) is used to prescribe drugs. It enables drug prescriptions to be ordered together with other orders as order sets for the implementation of clinical decision support, care pathways and care plans.
The name of the prescriber, location, date and time is system generated and is presented on the prescription when viewed by the pharmacist / dispenser.
LIST OF ORDERS (PRESCRIPTIONS)
Drug orders (prescriptions) should be facilitated by an order entry form that facilitates selection of drugs from standard lists
The Order entry form should have data fields allowing for the following data to be entered:
- Name of drug
- Order category (urgency, outpatient/inpatient etc)
- Other comments
Clinicians should order drugs either by their generic (chemical names) or the proprietary names. They need to define the route of administration, formulation, and dose. The system should convert generic and proprietary names chemical name for certain processes while for other processes (e.g. allergy checking, adverse drug reaction report) the name as given by the supplier would be used. Based on these details the application software should then select a suitable drug item available in the drug catalogue for the pharmacist to dispense. For example, it is not acceptable for a prescription to read Cap Ampicillin 250 mg, 500 mg 8 hourly. It should instead read as Cap Ampicillin 500 mg 8 hourly. The instruction from the system to the pharmacist should read as Cap Ampicillin 250 mg, 2 Capsules 8 hourly. There should be no absolute necessity for a clinician to know beforehand the drug concentration per item of a drug.
For purposes of prescribing, the drug list should be divided into the hospital’s formulary and non-formulary items.
The prescriber selects the drug from a list of formulary and non-formulary items using a search mechanism i.e. by typing in a few initial letters and the search engine should list similarly spelt words.
LIST OF ALL DRUGS (DRUG CATALOGUE)
The solution provider should make available a reliable drug database of all drugs available universally proprietary lists 9such as GDDB list, MIMS list, MULTUM list, First Data bank). This list should be updated as and when new drugs are introduced.
The PhIS should use this standard list or catalogue of drugs to create subsidiary lists of drugs for various purposes:
- Formulary items available in the hospital
- Formulary items not available in hospital
- Drug Control Authority (DCA) Approved Non-formulary items
- For decision support
- Drugs in allergy list
- Interactions list
- Reference table for drug history
The following data fields can be made mandatory in an order entry form:
- Dose including:
- Units of measure
- Route (oral tab/cap/oral syrup, intravenous, intramuscular, subcutaneous, intradermal etc.)
For dose, two fields need to be created. The amount should be a numeric field with defined decimal places. The unit of measure should be chosen (say using a drop down list) from an exhaustive list of units of measure including mg, mcgm, units, mls, satchet etc. The route should be chosen also from an exhaustive list of possible routes of administration (oral tab / cap/ oral syrup, intravenous, intramuscular, subcutaneous, intradermal, intrathecal, intracavity, vaginal suppository, rectal suppository, topical etc.).
These information should be presented in the manner that is useful for both the dispenser and the person administering the drug. The dispenser / pharmacist can determine which formulation of the drug to supply base on this data.
The frequency and the dosing interval are related but in practice the two are not equivalent. A patient on a frequency of three times per day (or tds) may not necessarily need to take the drugs strictly at 8 hour intervals (hence allow for uninterrupted sleep). The need to adhere to strict dosing intervals depends on the mechanism of action (first dose effect, post-antibiotic effect), half-life of the drug, therapeutic range, a minimum blood level / bio-availability required and therapeutic index (safety level). Where blood / tissue levels are not a critical factor, the frequency can be at preset times according to convenience of administration (o.d., o.n, e.o.d, bid, tds, qid). Where the dosing interval is critical drugs should be given at strict intervals (4 hourly, 6 hourly, 8 hourly, 12 hourly). The hospital should determine the frequency, intervals and time of administration as a policy. A standardized list of frequencies should be prepared for the prescriber to choose from.
Like dosage, duration requires two fields i.e. a numeric field and a unit of measure of time (seconds, minutes, hours, days, weeks, months). This information is useful for both the dispenser and the person administering the drug. The dispenser would use this information to calculate the amount of drug items to dispense. The function could also be performed automatically by the system. Default combination of dosage, route and frequency values (Order sentences) should be provided to the prescriber. Normally, to order each drug a doctor needs to view and select 6 values from 6 data fields. This could be very tedious. In practice each drug actually has a few constant combinations of dosage, route and frequency values. If these can be determined based on scientific considerations, empiric evidence, professional guidelines and common practice, default combination of dose; route and frequency values can be given to the prescriber as sentences. The system needs to interpret these sentences and automatically fill in the values in the relevant data fields.
It may not be wise to include duration in the default sentence as this may lead to wastage of drugs. For dosages and formulations where sentences have not been developed, the data fields need to be populated individually.
For outpatient clinics and services provided on a day-care basis, the system should allow the doctor to prescribe a single prescription (order) for the supply of medication for a fixed duration after the visit. For regular medication, the duration should coincide with the interval the current and the next visit. For this reason, drugs should be dispensed only after the follow up date is known. The dispenser should have access to the patient’s follow up plan.
The attending doctor should be able to place the order in the Clinical Information System and this order should create a task for the pharmacist to supply within the Pharmacy Information System via an interface between the two systems.
The pharmacist is able to vet the prescription for availability of the drugs, errors, accuracy-appropriateness of the dosage, possible drug interactions and any contraindications due to drug allergies or patient’s illnesses. The PIS should be capable of carrying out most of these vetting procedures automatically (aided by a decision support system).
The application software should provide the means for data regarding the drug prescriptions to be used to print label on packs and packets of various shapes and sizes.
The application software should provide the means for the prescriptions to be converted into a printable list to be used to:
- Select/pick drugs from their shelves or containers.
- Fill the packets or containers
- Dispensed to the patient at the dispensary counter
The application software should allow for quality control checks on picking-filling and the dispensing procedure to be performed and recorded. This can be aided by the use of bar-code scanners.
The administration of the drug would be performed by the patients themselves or their guardian / carer, except where directly observed administration (DOT) is used (discussed below).
OUTPATIENTS MEDICATIONS SUPPLY (DISPENSING)
The traditional method of communication between the prescriber and the dispenser is through a hand-written prescription slip. This would require data re-entry into the Pharmacy Information System, resulting in extra work and also predisposes to error. In a fully computerised and integrated system prescription is performed completely on line. This requires an interface but would reduce work and error. Processes can be initiated even before the patient arrives at the dispensary.
To dispense the prescription need to go through several steps i.e.
- Review the prescription
- Vet the prescription and query the prescriber if necessary
- Choose the suitable drug item as available in inventory
- Determine amount.
- Validate and finalise the task list which can be printed as a pick/fill listf. Print label and attach to packet
- Pick drug item from shelf / container
- Place drug in packet and then into a dedicated container
- Perform a quality control check
- Call and identify patient,
- Provide necessary information or education
- Hand over the drugs to the patient
The patient could be provided with a printed prescription to be presented to the counter. If the prescription slip is not provided, an alternative method of matching the patient with his/her prescription is to provide an order requisition with an order number.
Before supplying the medication, the pharmacist vets the prescription for availability of the drugs, errors, correct dosage, possible drug interactions and any contraindications due to drug allergies or patient’s illnesses. The PhIS should be capable of carrying out most of these vetting procedures automatically (aided by a decision support system).
The orders keyed in by the doctor, as discussed above, may not identify exact items and quantity to supply. The dispenser needs to select which suitable item to dispense (actual item for example 500 mg of Ampicillin is dispensed as 2 capsules of a proprietary product) from the inventory list. The system should be able to automatically calculate the number of items from the dose, frequency and duration.
The drugs are then selected, labelled and dispensed to the patient at the dispensary counter. The application software should assist the pharmacist to perform drug selection (Picking and Filling). A final list of items to dispense and labels for each item should be created. In practice, besides information on the computer screen, the printed prescription handed over by the patient and the labels are used as guides to pick items (pick list).
As a quality control step, another pharmacist should re-check items prepared against the task / pick list created from the prescription.
The dispenser should identify the patient by comparing his identifying document (Identity card or Visit card) against particulars on the task list before handing over the drug. He or she should acknowledge the completion of the task in the system.
Administration of the drug would be performed by the patients themselves or their guardian / carer. The exception would be directly observed administration (DOT) where patients take their medication under the supervision of pharmacy or clinical personnel. Examples include anti-tuberculosis drugs, methadone and drugs for some psychiatric patients. There should be a mechanism to record that the drugs have been administered (using the MAR or otherwise).
The system should have a method for identifying the dispenser. This can be through defaulting to the person opening the application (ID & Password) or a manual entry of name of dispenser.
(to be written)
Daily in-patient medications are medications given to patients while they are being warded. Unlike single prescriptions as in previously described scenarios, drug orders for in-patients change with changing needs. The pharmacy supplies the drugs based on orders placed by doctors (via the CIS). It is the clinical care providers in the wards / ICUs / Operation rooms (either nurses or doctors) who usually dispenses and administer the drug. Therefore because both parties need to know about any changes made, the ability to track changes is an important feature of the Pharmacy Information System for inpatients.
For in-patient prescriptions, the amount and duration of medication can be ordered as:
- Once only (stat)
- For a number of doses
- When required (prn limited by dosing interval)
- For a known duration.
Prescriptions are made as standing orders and remain effective until they are terminated. However prescriptions for a duration, may be terminated at the end of an interval (e.g. one week) requiring a re-order so as to encourage review of that medication.
INPATIENT SUPPLY METHODS
There are several ways of supplying drugs to inpatients, all of which may be used in a hospital.
Unit Dose System
In the unit dose system, drugs may be dispensed according to a doctor’s prescription as single dose packs on a daily dose basis. Only what the patient requires for a single day is supplied or replenished, once every day. Note that for in-patients, drugs are dispensed to nurses who retain custody of the drugs to be administered according to the prescription made by the doctor.
Unit of Use System
The unit of use system is another method is to dispense what the patient requires for the intended duration of therapy.
Administering from Floor Stock
For some drugs, the ward or any other inpatient/daycare location may be supplied with a stock of drugs. Nurses / medical assistants are usually given the responsibility and authority to control the stock. Both doctors and nurses may dispense and administer the drugs as prescribed (floor stock, emergency stock and buffer stock).
SUPPLY OF DRUGS FOR INPATIENT
In the inpatient situation drugs are not dispensed directly to patients but to their care provider (usually nurses). Orders made by doctors (the prescriber) are converted to tasks to supply by the pharmacy staff (the dispenser). A task list should be created. Drugs are supplied based on the prescription, the pharmacist needs to go through similar steps as in outpatient dispensing with some exceptions. For each patient location, the system provides the list of patients who are on medication (Prescription Sheet) is created in response to orders. The list would contain names of patients, their unique identifiers and their location (ward, bed number) and all the drugs prescribed for each patient. Supply is facilitated by providing a cart (mobile cupboard) for each location and each cart having containers/bins for individual patients. It is important to identify each container/ bin by a system generated bar-coded label (with name, unique identifier and location data). The system should provide instruction regarding the names of drugs and the quantity to be filled into each patient’s container.
This quantity depends on the supply system. If the unit of use system were used, then the system would calculate the quantity to last the whole duration of therapy is supplied. In the unit dose supply system the quantity sufficient for a day is calculated based on the frequency (times one day). Thereby the adequacy or excess of supply need to be reviewed regularly based on changes made to prescriptions by the doctor.
To supply, the pharmacist goes through each patient’s prescription. He/she then does the following preparatory tasks:
- Vet the prescription
- Determine the suitable drug item as available in inventory
- Determine amount to supply
- Create and validate list of drug items to be supplied for the patient i.e. the pick/fill list
The pick/fill list for each patient can be printed. Otherwise the list can be viewed from a hand-held computer.
Next, for each item on the pick/fill list, the pharmacist need to perform the following:
- Print a label and attach it to a packet
- Pick drug item from shelf / bin
- Place drug in the packet
- Identify patient, location and bed number
- Place drugs in the drawer within the trolley belonging to the right patient
- Perform a quality control check
- Send trolley to the right location
MEDICATION ADMINISTRATION RECORD (MAR)
For inpatients the dispensing process is replaced by the drug administration process. The patient would receive the drug only if it is administered to them. The doctor’s medication order (prescription) should create the task to supply in the PhIS and also create a task to administer the drug in the Clinical Information System. The nurse could read this task from the computer screen but in practice a printed list of updated tasks to administer medication for patients under the nurses’ care (similar to the prescription sheet) makes work easier and prevent omissions or errors. At no time should the nurse administer prescriptions transcribed by hand-writing from the screen onto paper.
Notwithstanding the method being used to prescribe and supply drugs, an accurate record of the medications (Medication Record) prescribed and given to the patient (when and by whom) need to be a part of the Clinical Information System that should be integrated with the Pharmacy Information System. The paper based prescription sheet (PS) provides instructions for the nurse to administer the medication at prescribed times. Hence at a glance she is able to see what drugs to be given and those that have been given. The computerized system should provide this functionality. Hence the electronic medication administration record (MAR) should display what medications the patient is currently on and when to administer them. She should be able to record that she has performed the task and the system should capture the time when this record was entered. In practice the Prescription Sheet (PS) and the Medication Administration Record (MAR) should be integrated (appear in one view) such that changes in prescription is reflected in task to administer.
The time to administer for every frequency interval is defined as a matter of policy by the health care facility. Hence a daily dose (o.d.) may mean to administer at 8.00 am, twice daily may mean 8 am and 8 pm, 8 hourly may mean 6am, 2 pm and 10 pm.
Because the MAR displays all medications that the patient is currently on, it may be used for vetting of prescriptions and drug reconciliation.
The MAR should provide pointers to both doctors and pharmacists regarding possibility of duplication and interaction. Drug reconciliation is performed by changing orders i.e. reducing dosage, cancelling a prescription or ordering an alternate drug
The vetting and validation process is discussed under decision support below. There are variations of the processes for in-patients and outpatients categories.
DISPENSING DISCHARGED IN-PATIENT MEDICATION
In-patients who are discharged from wards are also given a single prescription for supply of medication for a fixed duration. The doctor in charge in the ward prescribes by placing orders in the CIS-EMR. A similar process as for the outpatient medication order would follow.
The workflow and system requirements here are similar to the outpatient medication process.
The patient may obtain the drug from the dispensary counter or the drugs may be delivered to the patient (bed-side dispensing).
INVENTORY CONTROL FUNCTION
Inventory control is a major component of the Pharmacy Information System. Pharmacists need to know the drugs available (in the formulary), usage pattern and balance of stock. This inventory can be separate from or be a part of the Procurement and Storage Information System of the hospital’s integrated Management Information System.
The formulary is a database of reference information regarding drugs used and stocked in the hospital (name of drug, the dosages, routes and frequency of administration and costs).
SYSTEM REQUIREMENTS FOR DRUG INVENTORY CONTROL MANAGEMENT
An inventory control system would enable pharmacists to know what is available, maintain the stock level and also monitor usage of drugs. The stock level would be depleted with usage and topped up through procurement.
To supply a drug the actual items available in the pharmacy must be known. However, as discussed earlier drugs may be also be procured by the patient from some other sources.
Therefore a main list made up of inventory and non-inventory items need to be prepared. This is the list from which all other lists would be prepared including all medication orderables list and drug list for recording allergies (see below). Note however, even though users are presented with a list on the display monitor, in the database the list is part of a reference table. The columns of the table would contain data fields that includes the drug item identified by the chemical (generic) name (Cefoperazone 1 G Inj.), alternative trade name (Cefobid 1 G Inj.), manufacturer, supplier, and primary and secondary identifiers of the drug item (hospital / facility drug item code, national drug code, international drug code price etc. By using a using a code as a unique identifier, this reference table can be linked to other relations table.
Because dispensers would pick items from this inventory list, the system is able to update the stock level automatically.
The use of codes would simplify computer transactions, allow accurate data exchange with suppliers and between health care facilities. Data extraction and analysis would also be made easier.
DECISION SUPPORT SYSTEM IN PhIS
An essential component of the Pharmacy Information System is a decision support system that provides information on correct dosage, side effects, drug reactions, drug interactions and contraindications (e.g. allergies). This will enable the pharmacist to track, vet and verify drugs being prescribed. Some of the information required may originate from the EMR (e.g. allergies and diagnosis) or from the Laboratory Information System (e.g. for biochemical or microbiology results). It is obvious that the Pharmacy Information System need to be interfaced with many other systems within the Hospital Information System.
SYSTEM REQUIREMENTS FOR PHARMACY DECISION SUPPORT SYSTEM
At order entry, the system should be able to alert user regarding:
- medical alerts
- drug interactions
- chronic conditions e.g. chronic renal failure
- LMP as indicated
- Conflicting orders
- Duplicate orders
- Others as defined
Both the clinicians and the pharmacist need to know all the medications that the patient is on so as to minimize duplications, interactions and facilitate control.
Decision support can be provided to the doctor at the time of prescribing or to the pharmacist at the time of dispensing.
The use of defaulted combination of dosage, route and frequency values (order sentences) for a drug, described earlier, is one of the effective means of ensuring accuracy in dosage and frequency. More sophisticated decision support requires interface between the pharmacy Information System and the clinical information system and a purpose built Drug information – Decision Support System. Support can be in the form of alerts, advice or even disallowing transactions to proceed.
CHECKING FOR CORRECT DOSE
The Decision Support System needs to be fed with data on age, weight and height of patient from the Clinical Information System / EMR. The prescribed dose would then be compared with the recommended dose range for those parameters, and provide advice.
CHECKING FOR DRUG INTERACTIONS AND DUPLICATION
The system would feed all the names of drugs the patient is currently on to an interaction checklist. The doctor and or pharmacist would be informed of possible interactions and the transaction withheld. Doctors may be allowed to override the computers decision.
CHECKING FOR CONTRAINDICATIONS
Drugs may be contraindicated based on:
- Pregnancy status
- Biochemical parameters, including renal function, liver function and serum drug level.
It is obvious that the Decision Support System need to have real time information regarding the above parameters from the Clinical Information System.
CONTRAINDICATIONS DUE TO DRUG ALLERGY
Detection of contraindications due to drug allergy is possible if all allergies are documented as discrete data (not freetext). As such , when documenting allergy the clinician need to select the entry from a drug allergy list derived from either the drug name list / orderable list or the inventory list (depending on whether allergies to named drugs or actual supplied items are to be documented).
The definition of allergy, as opposed to tolerable side effect / effect of overdose, needs to be clear. Overzealous documentation may deprive patients of beneficial drugs. Doctors may be allowed to ignore allergy contraindication warnings.
DRUG PREPARATION FUNCTION
Even though most drugs used in the Hospital would be pre-prepared by the supplier, the following drug preparation function would be carried out:
- Cytotoxic drugs reconstitution
- Re-constitution of Total Parenteral Nutrition
- Intravenous fluid admixture (dilution of high concentration electrolytes, patient administered analgesic dugs, inotropes etc in intravenous fluid solution)
- The occasional extemporenous mixtures