Module 3

• specifically refers to the complete failure of the tissues to get adequate supply of oxygen

  Anoxia
• refers to the reduced supply of oxygen, and is the more appropriate term for the usual condition accompanying respiratory disorders.

  Hypoxia
• refers to reduced oxygenation of blood in the pulmonary circulation and is usually caused by primary diseases of the respiratory tract that prevents adequate ventilation of the alveoli, and blood-gas exchange

  Anoxic anoxia
• a deficiency of hemoglobin per unit volume of blood but the blood oxygen tension is normal

  anemic anoxia
• blood flow to and from the capillaries is reduced although the oxygen tension in both the atmosphere and the blood may be normal

  Stagnant anoxia
• results from the failure of the tissue to utilize oxygen in many oxidation processes in the presence of fully oxygenated blood

  Histotoxic anoxia
• depth and rate of respiratory movement increases. This increase is mediated by the chemoreceptors in the carotid and aortic bodies

  Hyperpnea
• The spleen contracts to express reserve blood into the circulation

  Splenic contraction
• More red blood cells are produced by the bone marrow. This may result in polycythemia (increased number of RBC)

  Erythropoiesis
• The heart rate and stroke volume also increase to maximize the delivery of oxygen to tissues.

  Positive chronotropism and inotropism
• associated with the retention of excessive carbon dioxide in the body when the compensatory mechanism fail

  Hypercapnea
• MANIFESTATION OF RESPIRATORY INSUFFICIENCY

  •Hyperpnea

  •Dyspnea

  •Cyanosis

  •epistaxis
• Drugs to increase respiratory secretion

  expectorants
• directly acting expectorants(EPCLP)

  Eucalyptus

  pine oil

  camphor

  lemon oil

  potassium iodide
• indirectly acting expectorants(AAPPG)

  ammonium carbonate

  ammonium chloride

  potassium iodide

  potassium citrate

  guaifenesin
• Drugs to inhibit or reduce respiratory secretion

  decongestants
• used to degrade inflammatory debris

  MUCOLYTICS AND PROTEOLYTIC ENZYMES
• used as an antidote to acetaminophen poisoning

  breaks the disulfide bonds in mucus and causing mucus to liquefy

  serves as a precursor of glutathione

  Acetylcysteine or carbocisteine
• been used with some success in the treatment of tracheobronchitis in dogs in conjunction with antibiotic therapy

  brings about an increase in the content of immunoglobulin and of administered oxytetracycline in bronchial secretion

  increases the volume and fluidity of respiratory secretion

  Bromhexine
• Proteolytic enzymes examples

  pancreatic dornase

  streptokinas-streptodornase

  trypsin
• drugs that are used to suppress cough. Should only  be used in cases of non-productive cough to prevent trauma to the respiratory tract

  ANTITUSSIVES
• what causes the depression of the cough center in the brain

  Central antittusives
• what soothes irritated respiratory mucus membrane

  Local antitussive
• non-selectively depress the cough center in the medulla oblongata and may also lead to depression of other parts of the CNS (narcosis).

  Narcotic antitussives
• selective action on cough center, but are deemed not to be habit-forming

  Non-narcotic antitussives
• cause relaxation of the bronchial smooth muscles, and increase the functional capacity of the respiratory tree

  BRONCHODILATORS
• useful as a prophylactic agent to prevent attacks in chronic bronchoconstrictor disorders.

  Cromolyn sodium
• have dual action to cause bronchodilation and reduction of inflammatory swelling of the respiratory tract

  Glucocorticoids
• are quite potent bronchodilators which act in the manner similar but not identical to the sympathomimetic

  Methylxantines
• direct stimulation of A2 adrenergic receptors in the bronchial smooth muscles resulting in bronchodilation

  Sympathomimetics
• has very potent prompt, but transient bronchodilator

  stimulates both alpha and beta adrenergic receptors

  useful for acute conditions where it can be given parenterally

  not ideal for use in chronic disorders because of fleeting effects.

  not effective to be given orally

  epinephrine
• pure Beta adrenergic stimulator

  comparable to epinephrine

  has potent cardiovascular effect.

  isoproterenol
• slow onset than epi and isop

  more prolonged effect (4-6 hours)

  better used in chronic disorders

  effective orally

  can cause marked CNS stimulation

  ephedrine