Respiratory & Neuromuscular Medications PDF

RESPIRATORY & NEUROMUSCULA R MEDICATIONS MEADINA G. CRUZ, MD PEDIATRIC INTENSIVIST Roadmap Why the need for medications? Review of the CNS, PNS and ANS Drugs for improving ventilation Neuromuscular Blocking agents Sedatives and Anxiolytics Two Primary Pu...

RESPIRATORY & NEUROMUSCULA R MEDICATIONS MEADINA G. CRUZ, MD PEDIATRIC INTENSIVIST Roadmap Why the need for medications? Review of the CNS, PNS and ANS Drugs for improving ventilation Neuromuscular Blocking agents Sedatives and Anxiolytics Two Primary Purpose of Drug Therapy in Patients using MV: 1. Provide patient comfort and 2. Facilitate airway management and mechanical ventilation Airway narrowing is a common complications in patients receiving mechanical ventilation Clinical Signs of Airway Distress Increasing PIP Wheezing Hypoxemia Agitation Causes of Airway Distress in Ventilated Pxs: 1. Pre-existing airway disease (Chronic Bronchitis, Asthma), 2. Drug-induced bronchospasm, 3. Accumulated secretions, and 4. Mechanical irritations  Whatever the cause, the distress must be recognized and corrected quickly to prevent hypoxemia and further deterioration. Along with bronchial hygiene procedures:  Bronchodilators & Corticosteroids - play a critical role in achieving optimal airway patency & constitutes the majority of nebulized drugs used in respiratory care Review of CNS, PNS & ANS A U T O N ON ME I R C V O S U Y S S T E M AUTONOMIC NERVOUS SYSTEM Involuntary Conducts impulses from CNS to cardiac muscles, smooth muscles, and glands Important Functions regulated: Respiration Heart rate BP Perspiration Glandular secretions  Autonomic Nervous System Sympathetic Parasympathetic DIVISION (stimulation results - (Stimulation causes - bronchodilatation) bronchoconstriction) Epinephrine(adrenaline NEURO- )/ Acetylcholine (ACh) TRANSMITE Norepinephrine - Cholinergic RS - Adrenergic (Receptors) Response (Receptors) Response © Cengage Learning 2014 Autonomic Nervous System Agents  Stimulants (Phenylephrine) Alpha- Sympathe 1 Inhibitors- tic Nonspecific Pathway Alpha- (Phentolamine) (Adrenergi Stimulants 2 c (Clonidine) Drugs Exerts Receptors Primarily Beta-1, Mild Effects ) on Beta-1 Beta-2 ANS Sympathetic Inhibitors (Esmolol, Agentand Atenolol) Inhibitors (Experimental Use sParasympat Beta-2 Only) hetic Stimulants (Albuterol, Pathways Formoterol) Commonly Used for Parasympath Bronchodilator Inhibitors -Effect Anticholinergic etic Pathway (Ipatropium) (Cholinergic Receptors) Stimulants - Anticholinergic (Methacholine)  Two ANS Pathways for Bronchodilatation Sympathetic Pathways Parasympathetic Pathways Stimulation of adrenergic Interference of Cholinergic response response Sympathomimetic activity Parasympatholytic activity (Stimulation of sympathetic (Inhibition of parasympathetic activity) activity) Relative increase of sympathetic Bronchodilatation activity © Cengage Learning 2014 Major Effects of Alpha () and Beta () Receptors Receptor Major Effects s Alpha - 1 Vasoconstriction; Pupillary Constriction Alpha - 2 Decreased GIT activity Positive inotropic affect ( muscular contractility) Beta - 1 Positive chronotropic effect ( heart © Cengage Learning 2014 rate)  Location of Alpha () and Beta () Receptors Recepto Location rs Mucosal blood vessels, Alpha Bronchial smooth muscles Beta - 1 Heart muscles Bronchial smooth muscles, Beta - 2 © Cengage Learning 2014 Peripheral mucosal blood vessels, CNS & peripheral limb muscles  Sympathomimetic Bronchodilators (Adrenergic Bronchodilators) Action Catecholami Inhalatio Frequenc Recepto Dosage nes n y r Epinephrine >-1>- 0.25 - 0.5 Neb (1%) QID (adrenaline) 2 mL >-1>- Neb 0.25 - 0.5 Racemic Epi QID 2 (2.25%) mL Isoproterenol Neb 0.25 - 0.5 © Cengage Learning 2014 -1