Respiratory Review 5

2 The respiratory stem includes the nose, nasal cavity, sinuses, pharynx, larynx, trachea, bronchial tree, and lungs. Air enters the nose, travels through the nasal cavity where the air is warmed. The air goes through the pharynx, which functions as a common duct for air and food.

3 Then the larynx, which is at the top of the trachea and holds the vocal cords allows passage of air. The trachea divides into the right and left bronchi on the way into the bronchial tree and the lungs.

4 The right lung has three lobes and the left lung has two lobes. Gas exchange occurs between the air and the blood within the alveoli which are tiny air sacs. Diffusion is the mechanism by which oxygen and carbon dioxide are exchanged.

5 Breathing is controlled by the medulla oblongata and pons. Inspiration is controlled by changes in the thoracic cavity. Air fills the lung because of atmospheric pressure pushing air in. Expansion of the lungs is aided by surface tension, which holds pleural membranes together.

6 In addition, the diaphragm, which is located just below the lungs, and stimulated by phrenic nerve acts as a suction pump to encourage inspiration. Expiration comes from the recoil of tissues and the surface tension of the alveoli.

7 Aerobic respiration occurs in the presence of oxygen and mostly takes place in the mitochondria of a cell. Anaerobic respiration occurs in the absence of oxygen and takes place in the cytoplasm of a cell. Both of these mechanisms occur in cellular respiration in humans. With anaerobic respiration glucose is broken down and produces less ATP when compared to aerobic respiration.

8 - Key Terms Anoxia - absence of oxygen in tissue Atelectasis - collapse of a lung Dyspnea - difficulty in the breathing cycle Hypercapnia - excessive carbon dioxide in the blood Tidal Volume - amount of air that normally moves in and out of the lungs

9-Medications for Lung Respiration Anticoagulants-Coumadin and Heparin limit ability to tolerate percussion. 2. Atropine- use for severe asthma, to help with spasms of the involuntary muscles and inhibit secretions.

10 - Medications for Lung Respiration 3. Bronchodilators- Epinephrine [e-pi·neph·rin], Alupent [a-lü-pent], Ventolin [Ven·to·lin], Proventil - Relax smooth muscle and open airway lumen. 4. Corticosteroids- Prednisone and Cortisol used to decrease edema and inflammation associated with COPD.

11 - Terminology A. Orthopnea-difficulty breathing in positions other than upright sitting and standing. B. Orthostatic hypotension - decrease in blood pressure upon assuming an erect posture. This is normal, but may be excessive resulting in fainting. C. Atelectasis - alveolar collapse involving part or all of the lung due to the complete absorption of gas or the inability of the alveoli to expand.

12 - Terminology D. Apnea - absence of respirations, usually temporary in duration. E. Bradycardia - Abnormally slow (low) pulse rate; below approximately 50 beats per minute. F. Cor pulmonale [cor pul·mo·na·le] - Right ventricular enlargement from a primary pulmonary cause

13 - Terminology G. Cheyne-Strokes respiration - breathing pattern characterized by a gradual increase in rate and depth followed by a gradual decrease; periods of apnea occur between cycles. H. Tachycardia - Abnormally rapid (high) pulse rate; over approximately 100 beats per minute.

14 - Terminology I. Beta-adrenergic blocking agents (beta-blockers) – Propranolol [pro·pran·o·lol], Metoprolol [met·o·pro·lol], nadolol [na·do·lol], Atenolol [a-ten·o·lol] , Timolol [tie·mo·lol]. J. Calcium channel blocking agent –Verapamil [ve·rap·a·mill], Nifedipine [nie·fed·i·peen], Diltiazem [dil·tie·a·zem] – A substance that inhibits the flow of calcium ions across membranes in smooth muscle. These drugs cause vasodilation [vay·zo·die·lay·sion] and relieve angina pain and coronary artery spasm.

15 - Terminology K. Ejection fraction - difference between left ventricular end diastolic volume and left ventricular end systolic volume. L. Digitalis - a drug that strengthens the contraction of the heart muscle, slows the rate of contraction of the heart, and promotes the elimination of fluid from body tissues.

16 - Terminology M. Antiarrhythmics –Lidocaine [lie·do·cane], Quinidine [quin·i·deen] , Procainamide [pro·cane·a·mide] , Disopyramide [die·so·py·ra·mide] , Phenytoin [phe·ni·to·in] (Dilantin) - Agents used to treat cardiac arrhythmias.

17 - Terminology N. Catecholamines [cat·e·ko·la·meens] - circulating compounds (epinephrine and norepinephrine) that are secreted by the sympathetic nervous system and the adrenal medulla; they act to increase cardiac rate, contractility, automaticity, and excitability.