NURS 5334 Module 4 Collaboration

Module 4 Collaboration Peripheral Nervous System Autonomic Parasympathetic - controls HR, gastric secretion, bladder/bowel, near eye vision, pupil constriction, and contracting the bronchial smooth muscle Neurotransmitter: acetylcholine Receptors: cholinergic receptors Subtypes: Nicotinic N, Nictonic M, Muscarinic To turn on the parasympathetic nervous system you use cholinergic agonists - Salivation, urination, lacrimation, defecation, emesis To turn off the parasympathetic nervous system you use anti-cholinergic antagonists - Can’t pee, can’t spit, can’t see, can’t shit Sympathetic Nervous System Body temp CV system Implements fight or flight Neurotransmitters: epinephrine, norepinephrine, dopamine Receptors: Alpha 1, Alpha 2, Beta 1, Beta 2, dopamine Adrenergic agonists to turn on the Sympathetic nervous system To turn off the sympathetic nervous system, you use adrenergic blockers or antagonists Sympathomimetic drugs are used to treat HTN, asthma, heart failure and angina pectoris Know what the receptors due in the body: Alpha 1: vasoconstriction, ejaculation, contraction of bladder neck and prostate Alpha 2: Located in presynaptic junction, Minimal clinical significance Beta 1: Heart; increased HR, force of contraction, velocity of conduction in AV node Beta 2: Bronchial dilation, Relaxation of uterine muscle, Vasodilation, Glycogenesis Dopamine: Dilates renal blood flow Cholinergic Agonists/Muscarinic Agonists Bethanechol: used to treat urinary retention: hypotension, asthma exacerbation, abd. cramps, diarrhea, increased salivation, increased tone and motility, dysrhythmias in patient with hyperthyroidism Cevimeline: used to treat dry mouth in Sjogren syndrome Pilocarpine: used to mainly for topical therapy of glaucoma Acetylcholine: used for pupil constriction after delivery in cataract surgery Muscarinic toxicity is treated with Atropine because Atropine has an anti-cholinergic affect Muscarinic antagonists block acetylcholine; these drugs are also known as parasympatholytic drugs, antimuscarinic drugs, muscarinic blockers and anticholinergic drugs. Atropine: Increases HR, relaxes bronchi, decreases tone of the urinary bladder detrusor, and decreased the tone and motility of the GI tract, mydriasis and cycloplegia (pupil dilation) Uses: Disorders of eye, muscarinic agonist poisoning, pre-anesthetic medication, asthma Adverse Reactions: urinary retention, constipation, tachycardia, asthma, dry mouth, blurred vision and photophobia Anti-cholinergic drugs are used for OAB and have cholinergic effects: Oxybutynin: OAB Darifenacin: is well tolerated reduces bladder symptoms w/no effects on brain or heart, Solifenacin: at a high dose can prolong QT intervals Careful with elderly on Beers List Scopalamine: used for motion sickness Ipratropium Bromide: used to treat asthma, COPD, rhinitis Dicyclomine: used for IBS Cholinesterase Inhibitors “Reversible” Cholinesterase Inhibitors: used to treat Myasthenia Gravis; Neostigmine Physostigme: used to treat muscarinic antagonist poisoning “Irreversible” Cholinesterase Inhibitors: primarily used as insectisides Adrenergic Agonists Sympathetic NS Alpha 1: vasoconstriction, mydriasis used for hemostasis, nasal congestion, delay absorption of local anesthesia, elevate BP, dilate pupils for surgery Side effects: HTN, necrosis, bradycardia Alpha 2: norepinephrine: relieve pain, outflow of blood to the heart Beta 1 receptors - stimulates the heart: epinephrine, Norepinephrine, isoproterenol, dopamine, dobutamine and ephedrine Therapeutic application: HF, shock, AV heart block, MI Beta 2: lungs, uterus Beta agonists used to: Asthma and delay preterm labor Dopamine: used for renal dilation Epinephrine: Alpha 1-2, Beta 1-2 Norepinephrine: Alpha 1-2 and Beta 1 - Used for cardiac arrest and hypotensive state Dopamine is beta 1 and alpha 1 at high doses - is used for shock Dobutamine: Beta 1 - Used to treat heart failure only use Phenylephrine: alpha 1 - Reduce nasal congestion - Dilate pupils - Delay anesthetic absorption Albuterol: Beta 2 - Treat asthma for bronchial dilation Ephedrine: Alpha 1-2, Beta 1-2 - Can benefit asthma by bronchodilation Adrenergic Antagonists These medications used for rest the sympathetic nervous system Alpha 1 blockade: treats BPH, Raynaud disease, Pheochromocytoma Can cause: Orthostatic hypotension, reflux tachycardia, sodium retention, nasal congestion, inhibition of ejaculation Alpha 2 Blockades Reflex tachycardia Angina, HTN, cardiac arrhythmias, reduce pain, infarct size Beta blocker cardio selective and non-cardioselective Cardioselective used in asthma and diabetic patients: Atenolol. Esmolol. Metoprolol. Bisoprolol. Non-cardioselective: Propranolol Labetolol Nadolol Carvedilol Beta 1 blockade (antagonists): Side effects: bradycardia, reduced cardiac output Beta 2 blockade (antagnonists): bronchoconstriction, hypoglycemia Always remember to wean off beta blockers cannot just take off medication; can cause rebound excitation Methyldopa: This is the preferred drug for the management of HTN during pregnancy Clonidine: is used for HTN, severe pain and can used in managing opioid withdrawal, facilitating cessation and Tourettes Syndrome Central Nervous System Passage across the blood-brain barrier limited to lipid-soluble drugs Parkinson’s Disease - Movement disorder with imbalance with acetycholine and dopamine, no cure - Tremor at rest, rigidity, bradykinesia, instability, loss of smell, loss of volume of voice - Treat the symptoms - Carbidopa and Levodopa - “Off” periods have way more dyskensias Levodopa/Carbidopa Most effective therapy for PD Levodopa is given with Carbidopa due to going through blood brain barrier Psychiatric disorders increase movement Dopamine Receptor Agonists - Ropinirole: can cause compulsive gambling, shopping, eating and hypersexuality - Pramipexole: COMT Inhbitors - Help with off periods - Entacapone Tolcapone The inhibit the COMT increase levels of Levodopa and adjunct treatment to Levodopa/Carbidopa Anticholinergics used as well with adjunct therapy Gradual loss-“wearing off”- develops near the end of the dosing interval and indicates that drug levels have declined to a subtherapeutic value