Introduction to Pharmacology Mucus

Mucus Controlling Strategies First, remove causative factors. Smoking/Pollution, Allergans Second, Optimize the tracheobronchial clearance. 1. Assure well hydrate 2. Cough and deep breath 3. CPT 4. Use a bronchodilator (May be used early for bronchospasm) 5. Use Mucolytics Use expectorants Third, reduce inflammation Treat infection Use corticosteriods Mucolytic breaking down, chemical breakdown of mucopolysaccharide by drug agents referred to as mucolytics Expectorant promotes expectoration increasing production or decreasing viscosity

Terminology Mucus – Total secretion from the mucous membranes including surface goblet cells and submucosal glands. Sputum – Expectorated secretions that contain respiratory tract as well as oro- and nasopharyngeal secretions. Gel – A macromolecular description of part of the respiratory secretion that has structure because of intermolecular attractions along with the properties of viscosity and elasticity.

Terms (cont) Sol – A macromolecular description of the respiratory secretion in true solution with the physical property of viscosity; designated as “airway surface fluid.” Glycoprotein – A protein with covalently attached oligosacchride units. The principle constituent of mucus; a high molecular weight glycoprotein gives mucus its viscosity.

Terms (cont) Oliogosaccharide – A sugar that is the individual carbohydrate unit of glycoproteins. Mucoactive – A term used for any agent that has an effect on mucus secretion. Mucolytic – Breaks down the structure of mucus usually reducing viscosity and elasticity. Act to change the properties of mucus, making it easier to be removed by cough or suctioning. Mucolytic Mucopolysaccharide: Amino sugars Amino acids Alternating Connected by disulfide bonds

Terms (cont) Mucokinetic – An effect of improving the mobilization and clearance of respiratory mucus secretions. Mucospissic – An effect of increasing the viscosity and elasticity of mucus secretion. Expectorant – An agent improving the expectoration of respiratory secretions.

Mucocilliary Physiology Approximately 100 ml of mucus is secreted each day for the average adult. These secretions are excreted by submucosal glands and surface goblet cells. Once the mucus is in the airway it is propelled up the tracheobroncial tree via ciliated epithelium cells. The cilia on the surface of these cells wave the mucus up the airway.

Mucocilliary Physiology (cont) The cilia are allowed to wave freely due to the sol layer (watery) of the mucus being found between the cilia. If this layer becomes more viscous than the waving ceases. As the cilia continue to wave, it mobilizes the gel layer up the airway. The average individual only expectorates 10% of the mucus produced with the remainder being absorbed by the inspired air, lymphatic system, or capillaries.

How Disease can Effect Mucus Clearance Disease, infection, or inflammation can cause hypersecretion of mucus. If too much mucus is produced the mucociliary escalator gets overloaded. Disease, infection, or inflammation can also increase viscosity and elasticity of the mucus. Therefore, slowing down ciliary movement. Mucociliary escalator Failure results in occlusion of the airway with thick viscous secretions Tell me which disease processes tend to have abnormal mucociliary function? Bronchitis, asthma, CF

How Disease can Effect Mucus Clearance (cont) If secretions are retained due to mucociliary impairment, then the patient is set up for infection. Microbes thrive in warm humid environment. This is especially the case if retained mucus is present. Mucus is an excellent nutrition substance for microbes to grow and multiply.

Acetylcysteine Brand name: Mucomyst Indications: Treatment of excessive thick, viscous mucus secretions, after other secretion clearing procedures have failed. Dose: 20% solution – 3–5 ml via SVN 10% solution – 6-10 ml via SVN May be directly instilled via ET tube or bronchoscope

Acetylcysteine (cont) Hazards: BRONCHOSPASM, airway inflammation, N/V, rhinorrhea, mechanical obstruction due to rapidly mobilization of thick secretions. Mode of Action: Breaks down the disulfide bonds in the mucus.

Dornase Alfa Brand name: Pulmozyme Indications: Daily management of CF. It’s the only agent that appears to breakdown viscosity without effecting elasticity. Dose: 1.0 mg in 2.5 ml of clear colorless sol. Delivered by itself via Hudson T Updraft II or the Marquest Acorn II Nebulizers.

Dornase Alfa (cont) Side effects: voice alteration, pharyngitis, laryngitis, rash, chest pain, and conjunctivitis Mode of Action: Breaks down the DNA.

Amiloride Indications: Investigated in CF patients. Through inhaling it was theorized that it would reverse the ion exchange defect found in CF. Not used today

Other Mucoactive Agents Sodium Bicarbonate Bland aerosol therapy