Pharmacotherapeutics Respiratory Drugs PDF

Pharmacotherapeutics Respiratory Drugs  Gas exchange is the process by which oxygen is transported to cells and carbon dioxide is transported from cells. Gas Impairment of gas exchange...

Pharmacotherapeutics Respiratory Drugs  Gas exchange is the process by which oxygen is transported to cells and carbon dioxide is transported from cells. Gas Impairment of gas exchange occurs when the diffusion of gases (oxygen and carbon dioxide) Exchange becomes impaired because of – Ineffective ventilation – Reduced capacity for gas transportation (reduced hemoglobin and/or red blood cells) – Inadequate perfusion Giddens, 2021  Individual Risk Factors Presence of chronic medical conditions, such as chronic obstructive pulmonary Age Smoking disease (COPD), cystic fibrosis (CF), heart failure (HF) Immunosuppression Reduced state of cognition Brain injury Prolonged immobility Gidd ens, 2021  Elements of Respiratory Assessment History Examination Past medical history Vital signs – Heart rate, respiratory rate, Family history blood pressure, temperature, oxygen saturation Current medications Inspection Lifestyle behaviors – Breathing effort – Skin color Occupation – Thorax Social environment – Extremities Auscultation of lung sounds Problem-based history Giddens, 2021  Laboratory tests Arterial blood gases, complete blood count, sputum, biopsy Common Radiologic studies Diagnostic Chest x-ray, CT and MRI scans, ventilation/perfusion (V/Q) scan, Tests positron emission tomography (PET) scan Pulmonary function studies Endoscopy Gidd ens, 2021  Clinical Management: Treatment strategies depend on Collaborative the underlying condition and the age of the patient Interventions – For each intervention, how does age affect safe and effective delivery of care? Gidd ens, 2021  Smoking cessation Pharmacotherapy Clinical Types of drugs Management: Medication administration Collaborative Interventions Nutrition therapy (Cont.) Positioning Chest physiotherapy Postural drainage Gidd ens, 2021  Clinical Management: Collaborative Interventions (Cont.) OXYGEN THERAPY AIRWAY SUCTIONING ENDOTRACHEAL TUBES MECHANICAL AND TRACHEOSTOMY INTUBATION TUBES CHEST TUBE MANAGEMENT Gidd ens, 2021 Asthma Recurrent and reversible shortness of breath Occurs when the airways of the lungs become narrow as a result of Bronchospasm Inflammation of the bronchial mucosa Edema of the bronchial mucosa Production of viscous mucus The alveolar ducts and alveoli remain open, but airflow to them is obstructed. Symptoms include wheezing and dyspnea (Sealock, Seneviratne, Lilley & Snyder, 2021)  Asthma A sudden and dramatic onset is referred to as an asthma attack. Prolonged asthma attack that does not respond to typical drug therapy is known as status asthmaticus. (Sealock, Seneviratne, Lilley & Snyder, 2021)  Asthma Management Continuum https://www.tandfonline.com/doi/full/10.1080/24745332.2021.1945887 Canadian Thoracic Society 2021 Guideline update: Diagnosis and management of asthma in preschoolers, children and adults Review how asthma is managed when controlled and uncontrolled SABA ICS LABA LTRA Bronchodilators – Relax bronchial smooth muscle, which causes dilation of the bronchi and bronchioles that are narrowed as a result of the disease process – Include β-adrenergic agonists and anticholinergics (Sealock, Seneviratne, Lilley & Snyder, 2021) (Sealock, Seneviratne, Lilley & Snyder, 2021) Short-acting ß-agonist (SABA) inhalers salbutamol (Ventolin®) Bronchodilators: Long-acting ß-agonist (LABA) inhalers ß-Adrenergic Agonists salmeterol (Serevent®), formoterol (Foradil®, Oxeze®) Long-acting ß-agonist and glucocorticoid steroid combination inhaler budesonide/formoterol fumarate dihydrate (Symbicort®) (Sealock, Seneviratne, Lilley & Snyder, 2021) Used during acute phase of asthmatic attacks Quickly reduce airway Bronchodilators: constriction and restore normal ß-Adrenergic airflow Agonists Agonists, or stimulators, of the adrenergic receptors in the sympathetic nervous system Sympathomimetics (Sealock, Seneviratne, Lilley & Snyder, 2021) Begins at the specific receptor stimulated ß-Adrenergic Agonists: Ends with dilation of the Mechanism airways of Action Activation of ß2-receptors activates cyclic adenosine monophosphate, which relaxes smooth muscle in the airway and results in bronchial dilation and increased airflow.  ß-Adrenergic Agonists Indications Contraindications Known drug allergy Uncontrolled cardiac Relief of bronchospasm related to asthma, chronic obstructive dysrhythmias pulmonary disease (COPD), and other pulmonary diseases Used in treatment and prevention of acute attacks (Sealock, Seneviratne, Lilley & Snyder, 2021) (Sealock, Seneviratne, Lilley & Snyder, 2021) Short-acting ß2-specific bronchodilating ß-agonist ß-Adrenergic Most commonly used drug in this class Agonists: Salbutamol Sulphate (Ventolin®) Oral, parenteral, and inhalational use Inhaled dosage forms include metered- dose inhalers (MDIs) as well as solutions for inhalation (aerosol nebulizers). (Sealock, Seneviratne, Lilley & Snyder, 2021) Long-acting ß2-agonist bronchodilator ß-Adrenergic Agonists: Never to be used alone Salmeterol but in combination with (Serevent®) an inhaled steroid Used for the maintenance treatment of asthma and COPD (Sealock, Seneviratne, Lilley & Snyder, 2021) Acetylcholine (ACh) causes bronchial constriction and narrowing of the airways. Anticholinergics bind to the ACh receptors, preventing ACh from binding. Anticholinergics Result: bronchoconstriction is prevented, airways dilate Example: ipratropium (Atrovent®) (Sealock, Seneviratne, Lilley & Snyder, 2021) Indirectly cause airway relaxation and dilation Help reduce secretions in COPD patients Indications: prevention of the bronchospasm associated with COPD; not for the management of ipratropium acute symptoms (Atrovent®) Oldest and most commonly used anticholinergic bronchodilator Available both as a liquid aerosol for inhalation and as a multidose inhaler Adverse effects - Dry mouth or throat, urinary retention (Sealock, Seneviratne, Lilley & Snyder, 2021) Leukotriene receptor antagonists (montelukast, zafirlukast) Corticosteroids (beclomethasone, Nonbronchodilating dexamethasone, fluticasone) Respiratory Drugs Mast cell stabilizers: rarely used and no longer included in Canadian Asthma Management Continuum (Sealock, Seneviratne, Lilley & Snyder, 2021) Nonbronchodilating Leukotriene A newer class of asthma medications Receptor Currently available drugs montelukast Antagonists (Singulair®) zafirlukast (Accolate®) (Sealock, Seneviratne, Lilley & Snyder, 2021) Leukotrienes are substances released when a trigger, such as pet dander or dust, starts a series of chemical reactions in the body. Leukotriene Leukotrienes cause inflammation, Receptor bronchoconstriction, and mucus production. Antagonists: Mechanism Leukotriene receptor antagonists prevent of Action leukotrienes from attaching to receptors on cells in the lungs and in circulation. Inflammation in the lungs is blocked, and asthma symptoms are relieved. (Sealock, Seneviratne, Lilley & Snyder, 2021) Leukotriene By blocking leukotrienes Prevent smooth muscle Receptor contraction of the bronchial airways Antagonists: Decrease mucus secretion Prevent vascular permeability Drug Effects Decrease neutrophil and leukocyte infiltration to the lungs, preventing inflammation (Sealock, Seneviratne, Lilley & Snyder, 2021) Leukotriene Prophylaxis and long-term treatment and prevention of Receptor asthma in adults and children – Montelukast safe in children 2 Antagonists: years of age and older Not meant for management of Indications acute asthmatic attacks Montelukast is also approved for treatment of allergic rhinitis Improvement with their use is typically seen in about 1 week  Leukotriene Receptor Antagonists (Sealock, Seneviratne, Lilley & Snyder, 2021) Contraindications Adverse Effects Known drug allergy May lead to liver dysfunction Previous adverse drug reaction Allergy to povidone, lactose, titanium dioxide, or cellulose derivatives— important to note because these are inactive ingredients (Sealock, Seneviratne, Lilley & Snyder, 2021) omalizumab (Xolair®) Monoclonal antibody antiasthmatic Selectively binds to immunoglobulin E, which in turn limits the release of Biologics for mediators of the allergic response Severe Asthma Omalizumab is given by injection. Potential for producing anaphylaxis Monitor closely for hypersensitivity reactions. (Sealock, Seneviratne, Lilley & Snyder, 2021) Anti-inflammatory properties Used in treatment of pulmonary diseases Corticosteroids Intravenous, oral or inhaled forms Inhaled form reduces systemic (Glucocorticoids) effects May take several weeks before full effects are seen (Sealock, Seneviratne, Lilley & Snyder, 2021) Methylprednisolone Prednisone Systemic Corticosteroids When would systemic steroids be used to treat asthma? (Sealock, Seneviratne, Lilley & Snyder, 2021) Stabilize membranes of cells that release harmful bronchoconstricting substances leukocytes (white blood cells) Increase responsiveness of Corticosteroids: bronchial smooth muscle to ß- adrenergic stimulation Mechanism of Dual effect of both reducing inflammation and enhancing the Action activity of ß-agonists Corticosteroids have also been shown to restore or increase the responsiveness of bronchial smooth muscle to ß-adrenergic receptor stimulation, which results in more pronounced stimulation of the ß2-receptors by ß-agonist drugs such as salbutamol. (Sealock, Seneviratne, Lilley & Snyder, 2021) Example: fluticasone propionate (Flovent®) Primary treatment of bronchospastic disorders to control the inflammatory responses that are believed to be the cause of these disorders Inhaled Persistent asthma Corticosteroids: Often used concurrently with the ß-adrenergic Indications agonists Systemic corticosteroids are generally used only to treat acute exacerbations or severe asthma. IV corticosteroids: acute exacerbation of asthma or other COPD (Sealock, Seneviratne, Lilley & Snyder, 2021) Drug allergy Not intended as sole therapy for acute asthma attacks Inhaled Corticosteroids: Contraindications Hypersensitivity to glucocorticoids Patients whose sputum tests are positive for Candida organisms (Sealock, Seneviratne, Lilley & Snyder, 2021) Pharyngeal irritation Coughing Inhaled Dry mouth Corticosteroids: Adverse Effects Oral fungal infections Systemic effects are rare because low doses are used for inhalation therapy. (Sealock, Seneviratne, Lilley & Snyder, 2021) Drug interactions are more likely to occur with systemic (versus inhaled) corticosteroids. Inhaled May increase serum glucose Corticosteroids: levels, possibly requiring Drug adjustments in dosages of Interactions antidiabetic drugs Greater risk of hypokalemia with concurrent diuretic use (e.g., furosemide, hydrochlorothiazide) (Sealock, Seneviratne, Lilley & Snyder, 2021) Encourage patients to take measures that promote a generally good state of health so as to prevent, relieve, or decrease symptoms. Nursing Implications Perform a thorough assessment before beginning therapy. (Sealock, Seneviratne, Lilley & Snyder, 2021) Teach patients to take bronchodilators exactly as prescribed. Nursing Ensure that patients know how to use inhalers and metered-dose inhalers, and have patients Implications demonstrate the use of the devices. Monitor for adverse effects. Monitor for therapeutic effects. (Sealock, Seneviratne, Lilley & Snyder, 2021) Salbutamol, if used too frequently, loses its ß2-specific actions at larger doses. Nursing As a result, ß1-receptors are stimulated, Implications: causing nausea, increased anxiety, palpitations, tremors, and increased heart rate. ß-Adrenergic Ensure that patients take medications Agonists exactly as prescribed, with no omissions or double doses. Educate patients to report insomnia, jitteriness, restlessness, palpitations, chest pain, or any change in symptoms. (Sealock, Seneviratne, Lilley & Snyder, 2021) Teach patients to gargle and rinse the mouth with lukewarm water afterward Nursing A ß-agonist bronchodilator and corticosteroid Implications: inhaler may both be ordered Inhaled Corticosteroids If a ß-agonist bronchodilator and corticosteroid inhaler are both ordered, the bronchodilator should be used several minutes before the corticosteroid to provide bronchodilation before administration of the corticosteroid. (Sealock, Seneviratne, Lilley & Snyder, 2021) Ensure that the medication is being used for long-term management of asthma, not Nursing acute asthma. Implications: Leukotriene Teach the patient the purpose of Receptor the therapy. Antagonists Improvement should be seen in about 1 week. (Sealock, Seneviratne, Lilley & Snyder, 2021) Teach patients to monitor disease with a peak flow meter. Encourage the use of a spacer device to ensure successful Nursing inhalations. Teach the patient how to keep Implications - inhalers and nebulizer equipment clean after use. Devices Devices Metered-dose inhalers (MDIs) Dry powder inhalers Small-volume nebulizers (Sealock, Seneviratne, Lilley & Snyder, 2021) For any inhaler prescribed, ensure that the patient is able to self- administer the medication. Provide a demonstration and a return demonstration. Ensure that the patient knows Inhalers: Patient the correct time intervals for inhalers. Education Provide a spacer if the patient has difficulty coordinating breathing with inhaler activation. Ensure that the patient knows how to keep track of the number of doses in the inhaler device. Giddens, 2021 “Self-management is the ability of individuals and/or their caregivers to engage in the daily tasks required to maintain health and well-being or to manage the physical, psychological, behavioral, and emotional sequelae of a chronic disease based on their knowledge of the condition, its consequences, and the plan of care co-developed with their health Self- care team.” Four important areas regarding self- management: Management Health enhancement and wellness Pre-disease/ disease prevention Disease/ new diagnosis Acute event management Education Preventive health measures Patient-centered plan of care Respects patient wishes and desires Giddens, 2021 Patient education is a process of helping people learn health- related behaviors so that they can incorporate these behaviors into everyday life. Patient Education Giddens, 2021 Learning domains refer to the type of learning in which a learner will be engaged. The three domains are: Patient Cognitive: increasing knowledge Education Psychomotor: developing or improving a skill Affective: changing or influencing attitudes Giddens, 2021 Patient Education as a Patient education provides a foundational role and provides Scope competency in the professional nursing practice. of Nursing Patient education is expected as a component of health care in all Practice settings and thus is applicable to all areas of the nursing practice involving patient care.  Assessment of a patient’s individual Giddens, 202) learning needs Education level Literacy level Social support Resources Developmental level Culture Planning Is determined by what teaching methods to use. Patient Is influenced by learning the domain used to achieve the outcome. Education Implementation Is influenced by the condition of the patient and competing priorities for the nurse. Evaluation Learning outcomes are consistent with the learning domain. Documentation - includes information taught and the patient’s motivation, ability to learn, developmental level, and resources. (Sealock, Seneviratne, Lilley & Snyder, 2021) Drugs that directly compete with histamine for specific receptor sites Histamine antagonists H1-antagonists (or H1-blockers) H2-antagonists (or H2 -blockers) Histamine is a major inflammatory Antihistamines mediator in many allergic disorders Allergic rhinitis Anaphylaxis Insect bite reactions Urticaria (Sealock, Seneviratne, Lilley & Snyder, 2021) H1-Antagonists (also called H1-blockers) Examples: chlorpheniramine, fexofenadine (Allegra®), loratadine (Claritin®), cetirizine Antihistamines (Reactine®), desloratadine (Aerius®), and Histamine diphenhydramine (Benadryl®) Antihistamines have several properties Antagonists Antihistaminic Anticholinergic Sedative (Sealock, Seneviratne, Lilley & Snyder, 2021) Antihistamines: H2-Blockers or H2-antagonists Used to reduce gastric acid in peptic ulcer H2-Blockers or disease H2-Antagonists Examples: cimetidine, ranitidine (Zantac®), famotidine (Pepcid AC®), nizatidine (Axid®) (Sealock, Seneviratne, Lilley & Snyder, 2021) Block action of histamine at H1-receptor sites Compete with histamine for binding at unoccupied receptors Cannot push histamine off the receptor if already Antihistamines: bound The binding of H1-blockers to the histamine receptors prevents the adverse consequences of Mechanism of histamine stimulation. Action Vasodilation Increased gastrointestinal, respiratory, salivary, and lacrimal secretions Increased capillary permeability with resulting edema (Sealock, Seneviratne, Lilley & Snyder, 2021) Antihistamines: More effective in preventing the actions of histamine than in Mechanism of reversing them Should be given early in treatment Action before all the histamine binds to the receptors (Sealock, Seneviratne, Lilley & Snyder, 2021) Cardiovascular (small blood vessels) Histamine effects: dilation and Histamine increased permeability (allowing substances to leak Versus into tissues) Antihistamine effects Antihistamine reduces dilation of blood vessels Effects Table increases blood vessels permeability 37.2 Smooth muscle (on exocrine glands) Histamine effects: stimulation of salivary, gastric, lacrimal, and bronchial secretions Antihistamine effects: reduction of salivary, gastric, lacrimal, and bronchial secretions Histamine Versus Antihistamine Effects Immune system (release of substances commonly associated with allergic reactions) – Histamine effects: mast cells release histamine and other substances, resulting in allergic reactions – Antihistamine effects: bind to histamine receptors, thus preventing histamine from causing a response (Sealock, Seneviratne, Lilley & Snyder, 2021) (Sealock, Seneviratne, Lilley & Snyder, 2021) Management of: Nasal & seasonal allergies Allergic reactions Antihistamines: Motion sickness Indications Parkinson’s disease Sleep disorders Also used to relieve symptoms associated with the common cold (Sealock, Seneviratne, Lilley & Snyder, 2021) Known drug allergy Cardiac disease, hypertension Kidney disease Asthma, chronic obstructive pulmonary disease (COPD) Antihistamines: Pregnancy Pediatric Considerations Contraindications Loratadine is not recommended for children younger than 2 years of age. (Sealock, Seneviratne, Lilley & Snyder, 2021) Anticholinergic (drying) effects: most common Dry mouth Difficulty urinating Antihistamines: Constipation Adverse Effects Changes in vision Drowsiness Mild drowsiness to deep sleep (Sealock, Seneviratne, Lilley & Snyder, 2021) example: loratadine (Claritin®) Developed to eliminate unwanted adverse effects Nonsedating Work peripherally to block the actions of histamine; thus, fewer Antihistamines central nervous system adverse effects Longer duration of action which increases adherence (Sealock, Seneviratne, Lilley & Snyder, 2021) example: diphenhydramine (Benadryl®) Traditional Older Antihistamines Have anticholinergic effects, making them more effective than nonsedating drugs in some cases (Sealock, Seneviratne, Lilley & Snyder, 2021) Educate patients to report excessive sedation, confusion, or hypotension. Antihistamines: Nursing Implications Teach patients not to take these medications with other prescribed or OTC medications without checking with their prescribers.