ppt chapter 22

Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Chapter 22

Drugs Stimulating the Central Nervous System

Chapter 22

Drugs Stimulating the Central Nervous System


Physiology Physiology • The CNS is responsible for providing control systems and

surveillance for many vegetative and conscious functions.

• The control of respiration occurs in the pons and medulla.

• At a synaptic level in the CNS, normal arousal mechanisms are affected through presynaptic release of neurotransmitters.

• CNS stimulants may provoke an increased release of neurotransmitters, a decreased reuptake of neurotransmitters, or an inhibition of postsynaptic enzymes.

• The result is a heightened postsynaptic response, leading to increased arousal.


Regulatory Centers of the BrainRegulatory Centers of the Brain


Narcolepsy Narcolepsy

• Narcolepsy is characterized by irresistible bouts of rapid eye movement (REM) sleep during nonsleep cycles.

• Associated features include disturbed nocturnal sleep and REM sleep disturbances.

• Additional symptom of cataplexy is a brief, sudden loss of motor control.

• Hypnagogic hallucinations are auditory, visual, or kinesthetic sensations without stimuli, appearing in the transition period between wakefulness and sleep.


Attention Deficit Hyperactivity Disorder Attention Deficit Hyperactivity Disorder

• Attention deficit hyperactivity disorder (ADHD) is the most prevalent chronic health issue affecting school-aged children.

• It is characterized by a persistent pattern of inattentiveness, hyperactivity, and impulsivity.

• Current research suggests that ADHD has a biologic basis.

• The management of ADHD is complex but usually involves pharmacotherapy with one or more of the CNS stimulants combined with behavior modification.


Overweight and Obesity Overweight and Obesity

• Obesity has become one of the major health issues in the United States.

• Overweight refers to an excess of body weight compared with set standards. The excess weight may come from muscle, bone, fat, or body water.

• Obesity refers specifically to having an abnormally high proportion of body fat.

• Weight regulation is multifactorial.

• Treating obesity involves a combination of different methods, including modifying eating behavior, implementing and maintaining an exercise program, and using adjunctive pharmacologic therapy to reduce appetite.


Respiratory Stimulation Respiratory Stimulation

• In patients at risk for postoperative pulmonary complications, respiratory depression may be a complication arising from chronic obstructive lung disease and frequent hypercapnia.

• Hypercapnia is a buildup of carbon dioxide levels that may result from pulmonary compromise.

• Preterm infants may experience hypercapnia because of their immature respiratory systems.

• Pharmacologic management of respiratory depression includes administering CNS stimulants, such as caffeine and doxapram.


Centrally Acting CNS Stimulants Centrally Acting CNS Stimulants

• The centrally acting CNS stimulants are drugs that stimulate the CNS directly or indirectly.

• This group of drugs includes the amphetamines, methylphenidate, pemoline, and cocaine.

• Prototype drug: dextroamphetamine (Dexedrine)


Dextroamphetamine: Core Drug Knowledge Dextroamphetamine: Core Drug Knowledge

• Pharmacotherapeutics

– Treatment of narcolepsy, ADHD, and obesity

• Pharmacokinetics

– Administered: oral. Metabolism: liver. Excreted: kidneys. Onset: 20 to 60 minutes. Duration: 5 hours

• Pharmacodynamics

– The exact mechanism of action is unknown.


Dextroamphetamine: Core Drug Knowledge (cont.)Dextroamphetamine: Core Drug Knowledge (cont.)

• Contraindications and precautions

– Cardiac disease, hyperthyroidism, and hypersensitivity

• Adverse effects

– Sudden death, stroke, MI, decreased appetite, rebound irritability, depression, headache, and jittery feeling

• Drug interactions

– Multiple drug interactions


Dextroamphetamine: Core Patient Variables Dextroamphetamine: Core Patient Variables • Health status

– Evaluate for preexisting conditions.

• Life span and gender– Pregnancy Category C drug

• Lifestyle, diet, and habits– Assess for consumption of caffeine.

• Environment– Assess the environment where the drug will be given.

• Culture and inherited traits– Determine if alternative therapies are used by the

patient.


Dextroamphetamine: Nursing Diagnoses and Outcomes Dextroamphetamine: Nursing Diagnoses and Outcomes • Disturbed Sleep Pattern related to drug effects or caffeine

use

– Desired outcome: The patient maintains normal sleep patterns through proper use of sleep hygiene measures and bedtime (hour of sleep [HS]) sedation.

• Delayed Growth and Development related to drug effects

– Desired outcome: The patient maintains a normal growth and development profile.

• Disturbed Sensory Perception related to drug response

– Desired outcome: The patient remains free from sensory and perceptual disturbances.


Dextroamphetamine: Nursing Diagnoses and Outcomes (cont.)Dextroamphetamine: Nursing Diagnoses and Outcomes (cont.)

• Imbalanced nutrition: Less than body requirements, related to amphetamine abuse and anorexia

– Desired outcome: The patient maintains adequate nutrition.

• Nonadherence to Therapeutic Regimen related to lack of motivation, poor self-image, or negative effects of the prescribed drug

– Desired outcome: The patient adheres to the drug regimen.


Dextroamphetamine: Planning and InterventionsDextroamphetamine: Planning and Interventions

• Maximizing therapeutic effects

– Administer with food in the morning and no fewer than 6 hours before bedtime

• Minimizing adverse effects

– Monitor for adverse effects.

– Monitor for rebound irritability and depression.


Dextroamphetamine: Teaching, Assessment, and EvaluationsDextroamphetamine: Teaching, Assessment, and Evaluations

• Patient and family education

– Discuss the importance of adherence to dosage schedule.

– Discuss adverse effects of the drug.

• Ongoing assessment and evaluation

– Monitor periodic growth and development data for children throughout therapy.

– Monitor for adverse effects.


QuestionQuestion

• Dextroamphetamine has which of the following effects on glucose levels?

– A. Increased

– B. Decreased


AnswerAnswer

• A. Increased

• Rationale: Dextroamphetamine can cause increased serum glucose levels. This is the reason why it is important for diabetic patients on this medication to monitor glucose levels more closely.


Anorectic Agents Anorectic Agents

• Obesity is a complex problem that is very difficult to treat.

• Although drug therapy is helpful, drugs alone cannot manage weight loss.

• Diet and exercise are equally important.

• Prototype drug: phentermine (Adipex-P)


Phentermine: Core Drug Knowledge Phentermine: Core Drug Knowledge


– Manages obesity by promoting weight loss

– DEA Schedule IV drug


– Administered: oral. Metabolism: liver. Excreted: kidneys


– Direct stimulation of satiety center in the hypothalamic and limbic regions


Phentermine: Core Drug Knowledge (cont.)Phentermine: Core Drug Knowledge (cont.)


– Arteriosclerosis, hypertension, glaucoma, cardiac arrhythmias

• Adverse effects

– Hypertension, constipation, insomnia, headache, and dry mouth


– MAOIs and SSRIs


Phentermine: Core Patient Variables Phentermine: Core Patient Variables

• Health status

– Assess for contraindications to therapy.

• Life span and gender

– Pregnancy Category C drug

• Lifestyle, diet, and habits

– Assess diet and make modifications.

• Environment

– Assess the environment where the drug will be given.


Phentermine: Nursing Diagnoses and Outcomes Phentermine: Nursing Diagnoses and Outcomes

• Imbalanced Nutrition: Less than Body Requirements, related to anorexia

– Desired outcome: The patient maintains adequate nutrition.

• Nonadherence to Therapeutic Regimen related to lack of motivation, poor self-image, or negative effects of prescribed drug

– Desired outcome: The patient adheres to drug regimen.


Phentermine: Planning and InterventionsPhentermine: Planning and Interventions


– Take daily.

– Exercise and low-calorie diet are important.


– Refrain from using drugs that may induce serotonin syndrome or elevate the blood pressure.


Phentermine: Teaching, Assessment, and EvaluationsPhentermine: Teaching, Assessment, and Evaluations


– Medication is only one component of weight loss.

– Discuss adverse effects and not taking with other OTC medication.


– Calculate BMI at each follow-up visit.

– Evaluating the patient routinely is important for assessing progress.


QuestionQuestion

• The cornerstone of weight loss is

– A. Drug therapy

– B. Exercise

– C. Healthy eating

– D. Both A and B

– E. All of the above


AnswerAnswer

• E. All of the above

• Rationale: Weight loss is a complex process that is multifactorial. Diet, exercise, and drug therapy are all a part of the process.


Respiratory Stimulants Respiratory Stimulants

• Respiratory stimulants are used to manage postsurgical respiratory depression and apnea in preterm neonates.

• Prototype drug: caffeine


Caffeine: Core Drug Knowledge Caffeine: Core Drug Knowledge


– Managing neonatal apnea, asthma, drowsiness, and fatigue


– Administered: oral or IV. Distribution: rapidly throughout the body; crosses the placenta and blood–brain barrier


– Direct stimulant at all levels of the CNS, which also stimulates the cardiovascular system


Caffeine: Core Drug Knowledge (cont.)Caffeine: Core Drug Knowledge (cont.)


– Anxiety disorders, panic disorder, or insomnia

• Adverse effects

– Tremor, sinus tachycardia, heightened attentiveness, diarrhea, excitement, irritability, and insomnia


– Oral contraceptives, psychostimulants, sympathomimetic agents, fluoroquinolone antibiotics, lithium, and MAOIs


Caffeine: Core Patient Variables Caffeine: Core Patient Variables

• Health status

– Assess for contraindications to drug therapy.

• Life span and gender

– Pregnancy Category C drug

• Lifestyle, diet, and habits

– Limit intake of food and beverages that contain caffeine.

• Environment

– Administration of IV form to neonates needs to be done in an environment where the neonate can be monitored closely.


Caffeine: Nursing Diagnoses and Outcomes Caffeine: Nursing Diagnoses and Outcomes

• Disturbed Sleep Pattern related to insomnia

– Desired outcome: The patient will maintain adequate sleep and rest cycles.

• Anxiety related to stimulatory effects of caffeine

– Desired outcome: The patient will remain calm throughout therapy.

• Deficient Fluid Volume related to diuretic effect of caffeine and potential diarrhea

– Desired outcome: The patient will remain well hydrated.


Caffeine: Planning and InterventionsCaffeine: Planning and Interventions


– Take medication as directed.

– Do not crush extended-release form of medication.


– Adhere to the contraindications and precautions for caffeine therapy.

– Limit ingestion of caffeine from food and beverage sources.


Caffeine: Teaching, Assessment, and EvaluationsCaffeine: Teaching, Assessment, and Evaluations


– Convey to the patient that caffeine is a drug and as such may create serious adverse effects

– Discuss adverse effects of the drug.


– When used for respiratory depression or neonatal apnea, monitor the patient’s vital signs carefully.

– When administering for migraine headaches, monitor for potential adverse effects.


QuestionQuestion

• What is the effect of giving caffeine to a patient with panic disorder?

– A. Improvement of symptoms

– B. Exacerbation of symptoms

– C. No effect on symptoms at all


AnswerAnswer

• B. Exacerbation of symptoms

• Rationale: Caffeine will cause exacerbation of panic disorder symptoms due to CNS stimulation.

ppt chapter 22

Documents

major health issues

obesity obesity

prevalent chronic health

prototype drug

acting cns stimulants

drug effects desired

drug response desired

management of adhd