The prescriber’s role

Medical practitioners are by far the major prescribers of medications. Increasingly, however, nurses working as nurse practitioners (NPs) prescribe within a specific scope of practice and associated formulary. In addition, it is not uncommon to find some settings where registered nurses (RNs) initiate medications for a specific client and from an approved list of medications (e.g. a nurse-initiated opioid analgesia protocol in emergency departments). The prescriber writes a medication order on a form in the client’s health record, in an order book, on a legal prescription pad or through a computer terminal.

The nurse’s role

The nurse prescribing (NPs only) or administering medications is accountable for knowing the medications prescribed, their therapeutic and non-therapeutic effects and the client’s need for the medication.

The nurse supervises the administration of the medication and provides education to the client and family about the medication and its effects. The nurse is responsible for assessing the client and their need for the medication before the dose, and then evaluating the effects of the medication after the dose and evaluating the outcome of this therapy.

The nurse, as and when appropriate, assesses the client’s ability to self-administer medications and provides client and family education about proper medication administration and monitoring. It is also important to note that different nursing roles may affect what a nurse can prescribe/administer. For example, NPs are able to prescribe certain medicines specifically relevant to their area of practice while enrolled nurses (ENs) may be limited in what they are able to administer by their agency’s policy.

The pharmacist’s role

The pharmacist prepares and dispenses prescribed medications. The pharmacist may also assess the medication plan and evaluate the client’s medication-related needs. The pharmacist is responsible for filling prescriptions accurately and ensuring that prescriptions are valid. The pharmacist in a healthcare agency rarely has to mix compounds or solutions, except in the case of some intravenous additive solutions. Most medication companies deliver medications in a form ready for use. Dispensing the correct medication, in the proper dosage and amount and with an accurate label is the pharmacist’s main task. The pharmacist acts as a valuable community and professional resource, providing information about medication action, side effects, toxicity, interactions and incompatibilities.

Names

A medication may have as many as three different names—the chemical name, a generic (non-proprietary) name and a trade name. A medication’s chemical name provides an exact description of the medication’s composition and molecular structure; chemical names are rarely used in clinical practice. An example of a chemical name is 7-chloro-1,3-dihydro-1-methyl-5-phenyl-3H-1,4-benzodiazepin-2-one. The generic name, for example, diazepam, is given by the manufacturer that first develops the medication. The generic name (written with a lowercase initial letter) is the name listed in official publications such as the British Pharmacopoeia and the MIMS Annual. The trade name, brand name or proprietary name (written with an uppercase initial letter) is the name under which a manufacturer markets a medication. The trade name has the symbol^® at the upper right of the name on the packaging, indicating that the manufacturer has registered the medication’s name (e.g. Valium^®). A drug may have several trade names. The following illustrates the three-name system:

Manufacturers choose trade names that are easy to pronounce, spell and remember so that the general public will recognise them and ask for specific brands. Many different companies may produce the same medication. Hospitals and clinic pharmacies dispense medications using the generic name to avoid confusion. The nurse finds medications under a variety of different names, however, and must be careful to obtain the exact name and spelling for a particular medication and check all trade names against the generic name to be sure the correct drug is given.

Nurses also need to be aware that some trade brands of the same generic medication may be able to be substituted safely (referred to as ‘brand name substitution’); for example, Febridol (trade name) can usually be substituted for Panadol (trade name) when a client is ordered paracetamol (generic name). However, in some situations not all trade brands of the same generic drug are equal, and so the prescriber/pharmacist should be consulted before a nurse substitutes trade brands. For example, when a client is prescribed the medication warfarin (generic name) it is important that Coumadin (trade name) is not substituted for Marevan (trade name), as they may not be bioequivalent (i.e. warfarin 5 mg of Coumadin may not be the same as warfarin 5 mg of Marevan).

Classification

Nurses must recognise the category or class to which medications with similar characteristics are allocated. Medication classification indicates the effect of the medication on a body system, the symptoms the medication relieves or the medication’s desired effect. For example, clients who have type 2 diabetes often take oral hypoglycaemic agents to help control their blood glucose levels. Usually, each class contains more than one medication that can be prescribed for the type of health problem. For example, there are more than five different types of oral hypoglycaemic agents. The physical and chemical composition of medications within a class may be slightly different. For example, two of the oral hypoglycaemic agents, a sulfonylurea and a biguanide, have different functions and are often prescribed together. A sulfonylurea stimulates the release of insulin from the pancreas, whereas a biguanide decreases the rate of hepatic glucose production. A prescriber chooses a particular oral hypoglycaemic medication based on how it works with the client’s symptoms or the client characteristics, cost, efficacy and dosing frequency. The prescriber may also choose based upon their own experience with the medication in other clients.

A medication may also be part of more than one class. For example, aspirin is an analgesic, an antipyretic, an anti-inflammatory and an anti-platelet medication. Often, the dose administered determines the class or action of the medication. An example of this is where a client may be prescribed antidepressants for neuropathic pain or the use of antihypertensive medicines for the treatment of heart failure.

Medications are available in a variety of forms or preparations (see Figure 31-1 and Box 31-1). The form of the medication determines its route of administration and speed of absorption. The composition of a medication is designed to enhance its absorption and metabolism. When administering a medication, the nurse must be certain to use the proper form that is appropriate to the client’s condition (e.g. syrup if swallowing tablets is difficult).

FIGURE 31-1 Forms of oral medications. Top row: Uniquely shaped tablet, capsule, scored tablet. Bottom row: Gelatin-coated liquid, extended-release capsule, enteric-coated capsule.

From Potter PA, Perry AG 2004 Fundamentals of nursing, ed 6. St Louis, Mosby.

Medication legislation and standards

The role of Australian governments in regulation of the pharmaceutical industry is to protect the health of the public by ensuring that medications are safe and effective. Control is exercised at three levels. The Therapeutic Goods Act 1989 (amendments made 2003; see www.tga.gov.au) regulates all drugs developed in or imported into Australia. It controls medication manufacture, sales and distribution, medication testing, naming and labelling, and the regulation of controlled substances. Advertising of some poisons to the public is also regulated by this Act.

The National Health Act 1953 applies to the Pharmaceutical Benefits Scheme that provides subsidised drugs to Australian residents. It also limits the amount of drugs supplied, and the number of times and frequency the supply can be repeated. Not all drugs are available at subsidised rates. Administration of medications by nurses is subject to further control by various regulations; some of the most important are listed in Box 31-2.

Poisons (including drugs) are listed in schedules (Box 31-3) that detail their availability to the public. For example, drugs listed in Schedule 4 are restricted to medical, dental or veterinary prescription (also includes NP prescription in some states). Official publications, such as the British Pharmacopoeia, set standards for medication strength, quality, purity, packaging, safety, labelling and dose form.

Absorption

Absorption refers to passage of medication molecules into the blood from the site of administration. Factors influencing medication absorption are the route of administration, ability of the medication to dissolve, blood flow to the site of administration, body surface area, pH and lipid solubility of the medication.

Distribution

After a medication is absorbed, it is distributed in the body to tissues and organs and ultimately to its specific site of action. The rate and extent of distribution depend on the physical and chemical properties of medications and the physiology of the person taking the medication.

Metabolism

Many drugs are metabolised into a less active or inactive form that is more easily excreted, either at the site of action or before the medication reaches its destination (hence the need for increased doses in some cases). This biotransformation occurs under the influence of enzymes that detoxify, degrade (break down) and remove biologically active chemicals. Most biotransformation occurs within the liver, although the lungs, kidneys, blood and intestines also metabolise medications. The liver is especially important, because its specialised structure oxidises and transforms many toxic substances and degrades many harmful chemicals before they become distributed to the tissues. If a decrease in liver function occurs, a medication may be eliminated more slowly, resulting in an accumulation of the medication and increasing a client’s risk of medication toxicity. For example, a small sedative dose of a barbiturate may cause a client with liver disease to lapse into a coma.

Excretion

After medications are metabolised, they exit the body through the kidneys, liver, bowel, lungs and exocrine glands.

The kidneys are the main organs for medication excretion. Some medications escape extensive metabolism and exit unchanged in the urine. Other medications must undergo biotransformation in the liver before being excreted by the kidneys. If renal function declines, then a client is at risk of medication toxicity. If the kidneys cannot adequately excrete a medication, it may be necessary to reduce the dose. Maintenance of an adequate fluid intake (50 mL/kg/day) promotes proper elimination of medications for the average adult.

The GI tract is another route for medication excretion. Many medications enter the hepatic circulation to be broken down by the liver and excreted into the bile. After chemicals enter the intestines through the biliary tract, the intestines may reabsorb them. Factors increasing peristalsis (e.g. laxatives and enemas) accelerate medication excretion through the faeces, whereas factors that slow peristalsis (e.g. inactivity and improper diet) may prolong a medication’s effects.

Gaseous and volatile compounds, such as anaesthetic gases and alcohol, exit through the lungs. Deep-breathing and coughing helps the postoperative client eliminate anaesthetic gases more rapidly. The exocrine glands excrete lipid-soluble medications. Good hygiene to promote cleanliness and skin integrity can prevent skin irritation when medications exit through sweat glands.

Nurses and mothers should check the safety of medications used while breastfeeding, as medications excreted through the mammary glands increase risk that a nursing infant will ingest the chemicals.

Therapeutic effects

The therapeutic effect is the expected or predictable physiological response a medication causes. Each medication has a desired therapeutic effect for which it is prescribed. For example, glyceryl trinitrate (Anginine) is used to reduce the cardiac workload and increase myocardial oxygen supply. A single medication may have many therapeutic effects. For example, morphine is an opioid analgesic, a vasodilator and releases antidiuretic hormone. The nurse must know the therapeutic effect of each prescribed medication so they can monitor the response of the medication and teach the client about the medication’s intended effect.

Adverse effects

Adverse effects are generally unexpected effects of the medication. These may be related to the pharmacological effect, the way an individual takes the medication or the individual’s response to the medication. When adverse responses to medications occur, the prescriber may modify the therapy or discontinue the medication. These effects may be called ‘side effects’ by consumers and non-healthcare professionals; however, it is important to note that these are unwanted effects rather than ‘allergic effects’. For example, a client may say they are ‘allergic’ to codeine as it makes them constipated. This is an adverse effect (i.e. unwanted effect), but it is not an allergic reaction.

ALLERGIC REACTIONS

Allergic reactions are an unpredictable response to a medication, and may represent as many as 24% of reported adverse drug reactions (Lazarou and others, 1998). A client can become immunologically sensitised to the initial dose of a medication. With repeated administration, the client develops an allergic response to the medication, its chemical preservatives or a metabolite. The medication or chemical acts as an antigen, triggering the release of the body’s antibodies. Allergic symptoms vary from mild (Box 31-5) to severe, depending on the individual and the medication. Antibiotics cause a high incidence of allergic reactions.

BOX 31-5 MILD ALLERGIC REACTIONS

Urticaria: raised, irregularly shaped skin eruptions with varying sizes and shapes; eruptions have reddened margins and pale centres.

Rash: small, raised vesicles that are usually reddened; often distributed over entire body.

Pruritus: itching of skin; accompanies most rashes.

Rhinitis: inflammation of mucous membranes lining nose; causes swelling and clear, watery discharge.

Severe or anaphylactic reactions are characterised by sudden constriction of bronchiolar muscles, oedema of the pharynx and larynx, severe wheezing and shortness of breath. The client may also become severely hypotensive, necessitating emergency resuscitation measures. Adrenaline, antihistamines and bronchodilators may be used to treat anaphylactic reactions. A client with a known history of a medication allergy should avoid re-exposure and wear an identification bracelet or medal (Figure 31-2) which alerts nurses, medical staff and emergency personnel to the allergy.

FIGURE 31-2 Allergy identification bracelet and medal.

From Potter PA, Perry AG 2013 Fundamentals of nursing, ed 8. St Louis, Mosby.

Medication interactions

When one medication modifies the action of another medication, a medication interaction occurs. These interactions are common in people taking several medications. A medication may increase or diminish the action of other medications, and may alter the way another medication is absorbed, metabolised or eliminated from the body. When two medications have a synergistic effect, i.e. work together, the effect of the two medications combined is greater than the effect of the medications when given separately. For example, alcohol is a central nervous system depressant that has a synergistic effect on antihistamines, antidepressants, barbiturates and opioid analgesics, making the client more sedated and lowering blood pressure/consciousness further.

A medication interaction is not always undesirable. Often the prescriber orders a combination of medications to create an interaction that will have a beneficial effect on the client’s condition. For example, where hypertension cannot be controlled with one medication, the client typically receives several medications that act together to control the blood pressure (e.g. diuretics and vasodilators). Multimodal analgesia is another good example of this (see Chapter 41).

Medication dose responses

After a medication is administered, it undergoes absorption, distribution, metabolism and excretion. The quantity and distribution of a medication in different body compartments change constantly. When a medication is prescribed, the goal is to maintain a constant and safe therapeutic serum level and take into account peaks, troughs, duration of action and plateaus (Box 31-6). Repeated doses are required to achieve this constant therapeutic plasma concentration of a medication because a part of a medication is always being excreted. The highest serum concentration (peak concentration) of the medication occurs when the rate of administration equals the rate of excretion. After peaking, the serum medication concentration falls progressively. With intravenous administration, the peak concentration occurs quickly but the serum level also begins to fall immediately (Figure 31-3).

FIGURE 31-3 The therapeutic range of a medication occurs between the minimum effective concentration and the toxic concentration.

From Lehne RA 2010 Pharmacology for nursing care, ed 7. St. Louis, Saunders.

All medications have a serum half-life, which is the time it takes for excretion processes to lower the serum medication concentration by half. This half-life is different for each medication. To maintain a therapeutic plateau, the client must receive regular fixed doses, the timing of which is based on the serum half-life. For example, analgesia is most effective when given on a regular around-the-clock basis, rather than a prn (as needed) basis in response to a client’s report of pain. In this way, an almost constant level of analgesia is maintained. After an initial loading dose, the client receives each successive dose when the previous dose reaches its half-life.

The client and nurse must follow regular dosage schedules and adhere to prescribed doses and dosage intervals. The prescriber, or the agency in which the nurse is employed, sets dosage schedules. When teaching clients about dosage schedules, the nurse should use language that is familiar to the client, for example ‘Take a dose in the morning and again in the evening’. Knowledge of the time of medication action also helps the nurse and client to anticipate a medication’s effect and the time of a therapeutic response. For example, when administering oral furosemide (Lasix), the nurse is aware a diuresis should occur in 1–2 hours; whereas when administering IV furosemide, a diuresis is expected in 20 minutes.

ORAL ADMINISTRATION

The oral route is the easiest and the most commonly used. Medications are given by mouth and swallowed with fluid. Oral medications usually have a slower onset of action and a more prolonged effect than parenteral (injected) medications, and their effect may be more unpredictable than other routes as many factors can affect GI absorption. Oral medicines enter the hepatic circulation once absorbed from the GI tract, and then travel to the liver where they need to ‘clear’ the liver before travelling on throughout the body. Some drugs are nearly totally destroyed by the liver (i.e. there is nothing left to travel throughout the body to act on their target cells) and so these medicines cannot be given orally (e.g. glyceryl trinitrate (GTN) or insulin). This situation is called the ‘first-pass effect’. Clients generally prefer the oral route, which is suitable for tablet or liquid forms of medications.

SUBLINGUAL ADMINISTRATION

Some medications are designed to be readily absorbed after being placed under the tongue to dissolve (Figure 31-4). A medication given by the sublingual (subling) route should not be swallowed, as the desired effect will not be achieved (i.e. it will not be absorbed into the bloodstream under the tongue where it can work immediately, but will travel to the stomach where it will be destroyed by the acidic environment or by the extensive liver metabolism). Glyceryl trinitrate is commonly given this way, by tablet or spray. The client should not take a drink until the medication is completely dissolved.

FIGURE 31-4 Sublingual administration of a tablet.

From Potter PA, Perry AG 2013 Fundamentals of nursing, ed 8. St Louis, Mosby.

BUCCAL ADMINISTRATION

Administration of a medication by the buccal route involves placing the solid medication in the mouth against the mucous membranes of the cheek, where it stays until it dissolves (Figure 31-5). Clients should be taught to alternate cheeks with each dose to avoid mucosal irritation. Clients are also warned not to chew or swallow the medication or to take it with any liquids, for the same reason as the sublingual route above. A buccal medication acts locally on the mucosa or systemically as it is swallowed in a person’s saliva.

FIGURE 31-5 Buccal administration of a tablet.

From Potter PA, Perry AG 2013 Fundamentals of nursing, ed 8. St Louis, Mosby.

PARENTERAL ADMINISTRATION

Parenteral administration involves injecting a medication into body tissues. The major sites of injection are:

Some medications are administered into body cavities other than the types listed above. Institutions vary regarding whether nurses are responsible for the administration of medications through these advanced techniques. The nurse often remains responsible for monitoring the integrity of advanced systems of medication delivery, for understanding the therapeutic value of the medication and for evaluating the client’s response to it, even when they do not administer the medication.

EPIDURAL

A common body cavity route is into the epidural space via a catheter placed by an anaesthetist. The epidural route is most commonly used for the administration of analgesia peri- and postoperatively (see Chapter 41). Nurses working in specialised areas (e.g. acute pain nurses, recovery room nurses) may administer drugs in bolus form (a small dose) or by continuous infusion.

INTRATHECAL

Intrathecal drugs are administered by an anaesthetist through a catheter placed into the subarachnoid space or into one of the ventricles of the brain. Intrathecal administration is often associated with long-term drug administration through surgically implanted catheters.

INTRAPERITONEAL

In the intraperitoneal technique, drugs (chemotherapeutics and antibiotics) are administered into the peritoneal cavity where they are absorbed into the circulation. One method of dialysis also uses the peritoneal route for the removal of fluid, electrolytes and waste products.

INTRAPLEURAL

In the intrapleural method, drugs are administered by a medical practitioner either directly through the chest wall or through a chest tube. Chemotherapeutics are the most common medications administered via this method. Medical staff also instil drugs that help resolve persistent pleural effusion to promote adhesion between the visceral and parietal pleura (pleurodesis).

INTRA-ARTERIAL

Intra-arterial infusions are administered directly into the arteries, and are used in clients with arterial clots. The nurse manages a continuous infusion of fibrinolytic (clot-dissolving) agents. The nurse must carefully monitor the integrity of this infusion to prevent inadvertent disconnection of the system and subsequent bleeding. It is important to note that nurses are not usually required to administer medicines intra-arterially and that inadvertent administration via this route will often result in severe tissue damage and amputation (in the cases of intra-arterial injections into limbs).

INTRAOSSEOUS

Intraosseous infusions are commonly given via the anterior surface of the tibia or alternatively into the iliac crest or spinal processes. They allow delivery of fluids, medication or blood into the bone marrow. Medication absorption is similar to the IV route.

OTHER PARENTERAL ROUTES

Other methods of drug administration that are usually limited to medical staff are intracardiac (injection of a drug directly into the cardiac tissue) and intra-articular (injection of a drug into a joint).

SKIN

Topical medications are applied to the skin by painting or spreading them over an area, applying moist dressings, soaking body parts in a solution or giving medicated baths. Systemic effects can occur if a client’s skin is thin, if the medication concentration is high or if contact with the skin is prolonged. Some medications (e.g. GTN and oestrogens) have systemic effects (i.e. work throughout the body, not just in the area where the medicine is applied) when applied topically by a transdermal disc or patch. The disc secures the medicated ointment to the skin. These topical applications may be applied for as little as 24 hours or as long as 7 days.

MUCOUS MEMBRANES

Medications can be applied to mucous membranes in a variety of ways:

INHALATION

The deeper passages of the respiratory tract provide a large surface area for medication absorption. Medications can be administered through the nasal passages, oral passage or endotracheal tubes via the client’s mouth or nose into the trachea (Figure 31-6). Medications administered by the inhalation route are readily absorbed into the bloodstream and work rapidly (they have local as well as systemic effects) because of the rich vascular alveolar–capillary network present in the pulmonary tissue.

FIGURE 31-6 Medication being instilled through endotracheal tube.

From Potter PA, Perry AG 2013 Fundamentals of nursing, ed 8. St Louis, Mosby.

INTRAOCULAR

Intraocular medication delivery involves inserting a medication similar to a contact lens into the client’s eye. The eye medication disc (usually an ocular lubricant) has two soft outer layers in which the medication is enclosed. The disc can remain in the client’s eye for up to a week.

EXAMPLES

The following example illustrates how to apply the formula. The prescriber orders the client to receive pethidine 75 mg IM. Thus the dose required is 75 mg. The medication is available only in ampoules containing 100 mg per 2 mL. Thus the stock strength is 100 mg in a volume of 2 mL. The formula is applied as follows:

The following example demonstrates how the formula applies to solid dose forms. The prescriber orders 0.125 mg PO of digoxin. The medication is available in tablets containing 0.25 mg.

Many tablets come with scores or indentations across the centre of the tablet (Figure 31-7). A scored tablet is easy to break in half for divided doses. In some institutions, pharmacists are responsible for scoring tablets. Unscored tablets should not be broken because of the potential for giving an incorrect dosage.

FIGURE 31-7 Scored medication.

Image: Dreamstime/Invisibleviva.

Often, liquid medications come prepared in volumes greater than 1 mL. The formula still applies. For example, the order is erythromycin suspension 250 mg PO. The pharmacy delivers bottles containing 100 mL with the labels stating ‘5 mL contains 125 mg of erythromycin’.

Here the nurse ignores the total volume available and instead uses the values (i.e. ‘5 mL contains …’) noted on the label. If the nurse calculated the dose on the basis of 100 mL available, the following error would occur:

On the basis of this calculation, the client would receive 20 times the desired dose.

Standing orders or routine medication orders

A standing order is carried out until cancelled by the prescriber, or until a prescribed number of days elapse. A standing order is usually written up in the client’s chart by the nurse who administers it and is countersigned by another nurse. A standing order may indicate a final date or a number of treatments or dosages. Many institutions have policies for automatically discontinuing standing orders. It is common practice for medical staff to have standing orders with regard to their clients’ premedications and antiemetics. In these cases, all of these clients will be given a particular premedication unless instructions to the contrary are given. Routine medication orders are written up by the medical officer and continue for the prescribed time, or number of doses, or until cancelled.

prn orders

A medication may be ordered to be given when required by a client. This is a pro re nata order (prn order). The nurse uses assessment skills and clinical judgment in determining whether a client needs the medication. Often, minimum intervals are set for the time of administration. This means the medication cannot be given more often than prescribed. Examples of prn orders are: ‘morphine sulfate 2 mg IV 4 hrly prn for pain’ or ‘metoclopramide 20 mg IM 8 hrly prn for nausea’.

When medications are administered, the nurse documents the assessment made and the time of medication administration. The nurse should frequently evaluate the effectiveness of the medication and record findings in the appropriate record. Often, prn orders include a range order (e.g. 7.5–10 mg) where nurses decide on the actual dose.

Single (one-time) orders

A medical practitioner may order a medication to be given only once at a specified time. This is common for preoperative medications or medications given before diagnostic examinations. An example is ‘temazepam 10 mg at 0900’ (preoperative medication).

Stat (statim) orders

A stat order signifies the immediate and once-only administration of a single dose of a medication. Stat orders are often written for emergencies when the client’s condition changes suddenly. For example: ‘Give hydralazine 10 mg IV stat’ (antihypertensive medication).

Some conditions change the status of a client’s medication orders. For example, surgery may necessitate a review of all of a client’s preoperative medications. Because the client’s condition changes after surgery, the prescriber may write new orders. When a client is transferred to another healthcare agency or to a different service within a hospital, or is discharged, the prescriber should review the medications and write new orders as indicated.

Stock supply system

With a stock system, medications are available in quantity in large multidose containers. This system is time-consuming and costly because a nurse must dispense each medication separately for a client. The stock system has been associated with a high rate of medication errors, and for this reason its use has declined. Opioids are often provided in stock supply and kept in a secure cupboard (for controlled or dangerous drugs) that complies with statutory requirements.

Unit-dose system

The unit-dose system uses portable medication trolleys containing a drawer with a 24-hour supply of medications for each client. The unit dose is the ordered dose of medication the client receives at one time. Each tablet or capsule is wrapped in a foil or paper container. At a designated time (daily, or in some cases weekly), the pharmacist refills the drawers in the trolley with a fresh supply. The trolley also contains limited amounts of prn stock medications for special situations. The unit-dose system is designed to reduce medication errors and saves steps in dispensing medications.

Client bedside storage system

In many clinical settings, medications are stored and dispensed from a locked cupboard at the client’s bedside. The nurse administers the medication at the required time. This system reduces the possibility of incorrect medication being given to the client, because only drugs required by the client are kept in the locked cupboard. Opioids and other Schedule 8 drugs are not legally able to be stored in this way.

ASSESSMENT

To determine the need for and potential response to medication therapy, the nurse assesses many factors.

NURSING DIAGNOSIS

Assessment provides data about the client’s condition, ability to self-administer medications and medication-use patterns, which can be used to determine actual or potential problems with medication therapy. Certain data are defining characteristics which, when clustered together, reveal nursing diagnoses (Box 31-7). For example, if a client admits missing a dose and there is evidence a medication has not decreased symptoms or there is limited clinical improvement, this may indicate non-adherence with a medication regimen. Once the diagnosis is selected, the nurse identifies influencing factors. Different interventions will be required for different factors, for example inadequate finances versus lack of knowledge. In the community, the nurse ensures that the client knows where and how to obtain medications. The nurse also assesses the client’s ability to read medication labels.

PLANNING

The nurse organises care activities to ensure the safe administration of medications. Hurrying to give clients medications can lead to errors. The nurse can also plan to use time during medication administration to teach clients about their medications. It is important to collaborate with the client’s family or support persons when instruction is given. Family members will often reinforce the importance of medication regimens in the home setting.

When clients are hospitalised, it is important to complete any education well before the day of discharge. Early planning is critical to allow time for questions and discussion so that the client understands medications and self-administration guidelines.

Whether a client self-administers or the nurse assumes responsibility for administering medications, the following goals and expected outcomes must be met:

IMPLEMENTATION

Acute care activities

When a nurse receives a medication order, several nursing interventions are essential for safe and effective medication administration.

RECEIVING MEDICATION ORDERS

A medication order is required for almost all medications to be administered by a nurse. Before any other interventions, the nurse ensures that the medication order contains all of the elements in Box 31-9. If the medication order is incomplete, the nurse should inform the prescriber and ensure completion before carrying out any orders. Some medication or treatment orders can be given verbally or by telephone by the prescriber to the nurse.

BOX 31-9 COMPONENTS OF MEDICATION ORDERS

A medication order is incomplete unless it has the following parts:

• Client’s full name. The client’s full name distinguishes the client from other persons with the same last name.

• Date the order is written. The day, month, year and time must be included. Designating the time an order is written helps clarify when certain orders are to stop automatically. If an incident occurs involving a medication error, it is easier to document what happened when this information is available.

• Medication name. The prescriber will order a generic or trade-name medication. Correct spelling is essential in preventing confusion with medications with similar spelling.

• Dose. The amount or strength of the medication is included.

• Route of administration. The prescriber uses common abbreviations for medication routes. Accuracy is important because some medications are administered by more than one route.

• Time and frequency of administration. The nurse needs to know when to initiate medication therapy. Orders for multiple doses establish a routine schedule for medication administration.

• Signature of medical officer or nurse practitioner. Signature makes the order a legal request.

CORRECT TRANSCRIPTION AND COMMUNICATION OF ORDERS

Generally, nurses in Australia and New Zealand are not responsible for the transcription of medication orders. If orders need reviewing or transferring to a new medication order sheet, it is the responsibility of the prescriber. There may be some exceptions in remote and rural practice and in specialist units, or in the role of the NP.

ACCURATE DOSAGE CALCULATION AND MEASUREMENT

When measuring liquid medications, the nurse uses standard measuring containers. The procedure for medication measurement is systematic to reduce the chance of error. The nurse calculates each dose when preparing the medication, pays close attention to the process of calculation and avoids any distractions.

CORRECT ADMINISTRATION

For safe administration, the nurse washes hands and uses non-touch or aseptic techniques and proper procedures when handling and giving medications. Certain medications require the nurse to perform assessments, for example assessing heart rate before giving antidysrhythmic medications. It is also essential that the nurse witnesses the client taking the medication.

RECORDING MEDICATION ADMINISTRATION

After administering a medication, the nurse records it immediately on the appropriate record form (Figure 31-11). The nurse never charts a medication before its administration—recording immediately after administration prevents errors, especially if the client refused the medication. The nurse needs only to record the time and initial the medication chart which already has the name of the medication, dosage, route, exact time of administration. Agency policies may also require the nurse to record the location of an injection.

FIGURE 31-11 National Inpatient Medication Chart (NIMC).

From Australian Commission on Safety and Quality in Health Care (ACSQHC) 2009 National Inpatient Medication Chart 2009 for acute care. Sydney, ACSQHC. Online. Available at www.safetyandquality.gov.au/our-work/medication-safety/medication-chart/nimc 4 Jul 2012. Used by permission of the Australian Government.

If a client refuses a medication or is undergoing tests or procedures that result in a missed dose, the nurse explains in the client’s progress notes the reason the medication was not given. Most agencies require the nurse to circle the prescribed administration time on the medication record when a dose is missed and, using the correct abbreviation, document the reason for the missed dose; for example, the client may be fasting before going to the operating theatre. It is also important to notify the prescriber, as missing some medicines may cause the client harm (e.g. refusing insulin when a blood-glucose level is high).

• CRITICAL THINKING

It is a client’s right to refuse treatment or medication. Should a nurse try to cajole or manipulate a client into taking their medicine? When might you be tempted to do this, and what should you do?

Administering medications to specific age groups

A client’s developmental level is a factor in how nurses administer medications. Knowledge of a client’s developmental needs helps the nurse anticipate responses to medication therapy.

INFANTS AND CHILDREN

Children vary in age, weight, surface area and the ability to absorb, metabolise and excrete medications (see Working with diversity). Children’s medication dosages are lower than those of adults, so special caution is needed when preparing medications for them. Medications are usually not prepared and packaged in standardised dose ranges for children, so preparing an ordered dosage from an available amount requires careful calculation. A child’s parents/caregivers are valuable resources for learning the best way to give medication to the child. Sometimes it is less traumatic for the child if a parent gives the medication and the nurse supervises.

All children require special psychological preparation before receiving medications. The nurse explains the procedure to the child using language appropriate to the child’s level of comprehension. Long explanations may increase a child’s anxiety, especially for painful procedures such as an injection. The young child who consistently refuses to cooperate, or resists despite explanation and encouragement, may require physical coercion. If so, it is carried out quickly and carefully. If possible, involve the child in decision making by saying ‘It’s time to take your tablet now. Do you want it with water or fruit juice?’ Never give the child the option of not taking a medication. After a medication is given, the nurse praises the child and may even offer a simple reward such as a star or token. It is important to check that the child has swallowed the medication. Box 31-7 gives some useful tips for administering medication effectively to children.

WORKING WITH DIVERSITY FOCUS ON CHILDREN AND ADOLESCENTS

From birth to adolescence, the paediatric client undergoes continuous physical growth and psychosocial development, much of which influences the outcomes of medication therapy.

PHYSICAL CONSIDERATIONS

• Absorption—gastrointestinal tract may decrease the bioavailability of some drugs and the absorption of others. Absorption from intramuscular injection sites can produce widely differing responses due to the size of the muscle mass and the blood flow to the injected area. Topical administration may produce variable results because the immature and relatively thin epidermis of infants and young children enables quick absorption of topically applied drugs.

• Distribution—body fat and water content vary widely with age, e.g. water as a percentage of bodyweight varies from 80% at birth to 56% at 12 months; it is 55% for adults. This variation determines absorption and distribution of the drug.

• Metabolism—immature liver function may affect drug metabolism and the half-life of a drug.

• Excretion—renal development reaches adult level at around 12 months of age. Immaturity and relative lack of renal excretion can prolong the action of drugs.

Accuracy in paediatric dose calculation is essential to avoid possibly fatal errors.

OLDER ADULTS

Older adults also require special consideration during medication administration (see Working with diversity). In addition to the physiological changes of ageing (Figure 31-12), behavioural, cultural and economic factors influence an older person’s use of medications. Ebersole and Hess (2004) describe five behavioural patterns characteristic of the older client in relation to medication use:

• Polypharmacy. The client takes several prescribed or over-the-counter (OTC) preparations to treat several disorders/symptoms simultaneously. There exists a high risk of medication interactions with other medications and with foods, and an increased risk of adverse medication reactions.

• Self-prescribing of medications. A variety of symptoms experienced by elderly clients, such as pain, constipation, insomnia and indigestion, are amenable to OTC medications. Older adults often seek relief from problems by OTC preparations and/or complementary medicines and herbs.

• Over-the-counter medications. These medications, which can be purchased without a prescription, are available from pharmacies, supermarkets and health shops. It is known that OTC medications are widely used by older people to relieve symptoms. Many of these preparations have ingredients which, when used inappropriately, may cause undesirable side effects, adverse reactions or may be contraindicated for the client’s condition. Clients should be asked specifically about ‘other things you are taking’.

• Misuse of medications. Forms of misuse by older clients include overuse, underuse, erratic use, contraindicated use and using medication prescribed for others.

• Non-adherence (non-compliance). Non-adherence is defined as a deliberate misuse of medication. Many older adults intentionally do not adhere to their medication regimen; they often alter the dose because of cost, ineffectiveness or uncomfortable side effects. Non-adherence may also be a result of poor eyesight, cognitive factors or inadequate education.

FIGURE 31-12 Ageing body and drug use.

From Lewis SM and others 2003 Medical–surgical nursing, ed 6. St Louis, Mosby.

EVALUATION

The nurse monitors a client’s response to medications on an ongoing basis, so must know the therapeutic action and common side effects of each medication. A change in a client’s condition can be physiologically related to health status or may result from medications, or both. The nurse must be alert for reactions in a client taking several medications. The goal of safe and effective medication administration involves a careful evaluation of technique, as well as the client’s response to therapy and ability to assume responsibility for self-care.

To evaluate the effectiveness of nursing interventions, the nurse identifies whether nominated client outcomes were met using evaluative measures (Table 31-4). Direct observation of behaviour or response, rating scales (e.g. the numerical pain rating scale), checklists and oral questioning are all of use when evaluating the outcome of medication administration. The reading skill and knowledge level of the client, and cognitive and psychomotor ability, must also be considered. Physiological measures (e.g. blood pressure, heart rate and visual acuity) are the most common type of measurement used by the nurse. Client statements can also be used as evaluative measures. The findings of an evaluation should be measured against baseline information gained before the medication was given (e.g. pain scores before and after the administration of analgesics).

TABLE 31-4 EXAMPLE EVALUATION OF GOALS