Respiratory lecture

  1. What is ventilation?
    movement of air in and out of airways
  2. What is perfusion?
    getting the air that is in the alveoli to diffuse by Henry's law
  3. ways perfusion can be prevented
    blood clots, decreased blood flow, decreased blood volume
  4. upper airway
    nose, paranasal sinuses, pharynx, tonsils, adenoids, larynx, trachea
  5. lower airway
    lungs - pleura, mediastinum, lobes, bronchi, bronchioles, alveoli
  6. What is shunting?
    • perfusion is better than ventilations
    • low ventilation - perfusion ratio
    • perfusion exceeds ventilation

    blood bypasses the alveoli without gas exchange occuring

  7. causes of shunting
    • pneumonia
    • atelectasis
    • tumor
    • mucus plug
  8. What is dead space?
    • ventilation is better than perfusion
    • high ventilation - perfusion ratio
    • ventilation exceeds perfusion

    alveoli do not have an adequate blood supply for gas exchange to occur
  9. causes of dead space
    • pulmonary emboli
    • pumonary infarction
    • cardiogenic shock
  10. What is a silent unit?
    • no ventilation or perfusion
    • absence of both ventilation and perfusion or with limited ventilation and perfusion
  11. causes of a silent unit
    • pneumothorax
    • severe acute respiratory distress syndrome
  12. what are some elderly considerations when discussing ventilation and perfusion?
    • airways of alveoli thicken and become less compliant
    • airways have more dead space
    • surface area available for exchange of oxygen and carbon dioxide decreases
    • alveoli begin to loose elasticity around age 50
    • decrease in vital capacity occurs w/ loss of chest wall mobility --> restricts tidal flow of air
    • decreased diffusion capacity for O2 w/ increasing age --> produces lower O2 levels in arterial circulation
    • decreased ability to rapidly move air in and out of lungs
  13. normal ventilation:perfusion ratio
    varies in different areas of lungs
  14. things that may alter perfusion
    • change in pulmonary artery pressure
    • change in alveolar pressure
    • change in gravity
  15. things that may alter ventilation
    • airway blockages
    • local changes in compliance
    • changes in gravity
  16. what is compliance?
    measure of the force required to expand or inflate the lungs
  17. 4 possible states of gas exchange in lungs
    • normal (V/Q) ratio
    • shunting (low V/Q ratio)
    • dead space (high V/Q ratio)
    • silent unit (no ventilation or perfusion)
  18. What is the main cause of hypoxia after thoracic or abd surgery and most types of respiratory failure?
  19. What is the purpose of a pulse oximetry?
    it's a noninvasive way to see if the pt is being oxygenated
  20. What does the oxyhemoglobin dissociation curve show?
    the relationship between the partial pressure of oxygen (PaO2) and the percentage of saturation of oxygen (SaO2)
  21. What is PaO2?
    partial pressure of alveolar oxygen
  22. What is partial pressure?
    the pressure exerted by each type of gas in a mixture of gases
  23. What is SaO2 and what can affect it?
    • percentage of saturation of oxygen
    • affected by:
    •    carbon dioxide
    •    hydrogen ion concentration
    •    temperature
    •    2,3-diphosphogycerate
  24. What does an increase in SaO2 do to the oxyhemoglobin dissociation curve?
    shifts to right
  25. What happens when the oxyhemoglobin dissociation curve shifts to the right?
    less oxygen is picked up in the lungs, but more oxygen is released to the tissues if PaO2 is unchanged

    bonds are more loose

  26. What does a decrease in SaO2 do to the oxyhemoglobin dissociation curve?
    shifts to left
  27. What happens when the oxyhemoglobin dissociation curve shifts to the left?
    more oxygen is picked up in the lungs, but less oxygen is given up to the tissues if the PaO2 is unchanged

    bonds between oxygen and hemoglobin become stronger

  28. What is the normal pH of arterial blood?
  29. What is the normal Co2 of arterial blood?
  30. What is the normal HCO3 of arterial blood?
  31. When a pH is below 7.35, it is said to be ___________.
  32. When a pH is above 7.45, it is said to be ___________.
  33. The ______ regulate the CO2 and can be corrected ________.  Normally a(n) ________.
    • lungs
    • easily
    • acid
  34. The _______ regulate the HCO3 and is ______ to fix.  Normally a(n) ________. 
    • kidneys
    • longer
    • base
  35. What are the characteristics of uncomensated ABG?
    • abnormal pH
    • one abnormal value
    • one normal value

    acute condition
  36. What are the characteristics of a partially compensated ABG?
    • abnormal pH
    • two abnormal values
    • (ALL abnormal)
  37. What are the characteristics of a compensated ABG?
    • normal pH
    • 2 abnormal values

    chronic condition
  38. low pH
    low HCO3
    normal CO2
    metabolic acidosis
  39. high pH
    high HCO3
    normal CO2
    metabolic alkalosis
  40. low pH
    high CO2
    normal HCO3
    respiratory acidosis
  41. high pH
    low CO2
    normal HCO3
    respiratory alkalosis
  42. causes of normal anion gap metabolic acidosis
    • *most commonly due to renal failure
    • diarrhea
    • lower intestinal fistulas
    • ureterostomies
    • use of diurectics
    • early renal insufficiency
    • excessive administration of chloride
    • administration of parenteral nutrition w/o bicarb or bicarb producing solutes (lactate)
  43. causes of high anion gap metabolic acidosis
    • ketoacidosis
    • lactic acidosis
    • late phase of salicylate poisoning
    • uremia
    • methanol or ethylene glycol toxicity
    • ketoacidosis w/ starvation
  44. signs and symptoms of metabolic acidosis
    • HA
    • confusion
    • drowsiness
    • ^ RR and depth
    • N/V
    • dysrhythmias
    • peripheral vasodilation and decreased cardiac output when pH <7
    • decreased BP
    • cold, clammy skin
    • shock
  45. treatment for metabolic acidosis?
    • directed at correcting metabolic imbalance
    •      decrease chloride intake if that is the problem
    • administer bicarb when necessary
    • monitor K+ level closely

    if chronic, low Ca+ treated before  chronic metabolic acidosis treated to avoid tetany from increase in pH and decrease in ionized Ca+

    may receive hemodialysis or peritoneal dialysis
  46. causes of acute metabolic alkalosis?
    • *most common cause is vomiting or gastric suctioning
    • pyloric stenosis (only gastric fluid is lost)
    • loss of K+
    •      diuretic therapy that promotes excretion of K+ (thiazides, furosemide)
    •      excessive adrenocorticosteriod hormones (hyperaldosteronism, Cushing's syndrome)
    • excessive alkali ingestion from antacids containing  bicarb
    • use of Na+ bicarb during CPR
  47. causes of chronic metabolic alkalosis?
    • long term diuretic therapy use
    • villous adenoma
    • external drainage of gastric fluids
    • significant K+ depletion
    • cystic fibrosis
    • chronic ingestion of milk and calcium carbonate
  48. signs and symptoms of metabolic alkalosis
    • tingling of fingers and toes
    • dizziness
    • hypertonic muscles
    • symptoms of hypocalcemia
    • respirations are depressed as a compensatory action
    • atrial tachycardia
    • ventricular disturbances may occur
    • frequent PVC's or U waves seen as K+ decreases
  49. treatment of metabolic alkalosis
    • aimed at correcting underlying acid-base disorder
    • monitor I&O's closely (b/c of volume depletion w/GI loss)
    • administer chloride so kidneys can absorb Na+ w/ Cl- (allows excretion of excess bicarb)
    • restore normal fluid volume w/ NaCl solutions
    • administer K+ if hypokalemic
    • H2 receptor agonist to reduce production of gastric acid to reduce metabolic alkalosis associated w/ gastric suctioning (ex. Tagament)
    • Carbonic anhydrase if can't tolerate rapid volume expansion (CHF)
  50. what ALWAYS causes of respiratory acidosis?
    • inadequate excretion of CO2 w/ inadequate ventilation
    •    causes elevation in plasma CO2 levels
  51. causes of acute respiratory acidosis in emergency situations
    • acute pulmonary edema
    • aspiration of foreign object
    • atelectasis
    • pneumothorax
    • overdose of sedatives
    • sleep apnea
    • administration of oxygen to a pt w/ chronic hypercapnia (excessive CO2 in blood)
    • severe pneumonia
    • ARDS
    • mechanical ventilation if rate is inadequate and CO2 is retained
  52. what disease processes can cause respiratory acidosis?
    • muscular dystrophy
    • myasthenia gravis
    • Guillain-Barre syndrome
  53. causes of chronic respiratory acidosis
    • pulmonary diseases
    •    emphysema
    •    bronchitis
    • obstructive sleep apnea
    • obesity
  54. what happens if the PaCO2 does not exceed the bodies ability to compensate?
    pt will be asymptomatic
  55. why do pts w/ COPD  who gradually accumulate CO2 over a prolonged period of time not develop symptoms?
    compensatory renal changes have had time to occur
  56. signs and symptoms of respiratory acidosis
    • ^ pulse
    • ^RR
    • ^ B/P
    • mental cloudiness
    • feeling of fullness in head
    • v-fib in anesthetized pt
    • ^ ICP if severe
    • papilledema
    • dilated conjuctival blood vessels
    • hyperkalemia
  57. treatment of respiratory acidosis
    • directed at improving ventilation
    • bronchodilators to reduce bronchial spasms
    • antibiotics to fight infection
    • thrombolytics or anti-coagulants for PE
    • pulmonary hygiene measures to clear respiratory tract of mucus and purulent drainage
    • adequate hydration to keep mm moist and facilitate removal of secretions
    • supplemental O2 w/ caution if necessary
    • mechanical ventilation if used appropriately
    • semi-Fowler's position to expand chest wall
  58. what ALWAYS causes respiratory alkalosis?
  59. what causes hyperventilation in respiratory alkalosis?
    • extreme anxiety
    • hypoxemia
    • early phase of salicylate intoxication
    • gram-negative bacteremia
    • inappropriate ventilator settings that do NOT match pt requirements
  60. what causes chronic respiratory alkalosis?
    • chronic hypocapnia
    • chronic hepatic insufficiency
    • cerebral tumors
  61. signs and symptoms of respiratory alkalosis
    • lightheadedness due to vasoconstriction and decreased cerebral blood flow
    • inability to concentrate
    • numbness and tingling
    • tinnitus
    • LOC
    • ^ HR
    • ventricular and atrial dysrhythmias
  62. treatment of respiratory alkalosis
    depends on underlying cause

    if caused by anxiety, pt instructed to breath more slowly or into closed system (paper bag) to increase CO2

    sedative may be needed to relieve hyperventilation
  63. sputum studies collection
    • requires doctor's order
    • can be collected by nurse
    • best to collect early in morning
    • can instruct pt to collect specimen themselves
    • should send to lab as soon as collected
  64. 2 things a pt can do that can contaminate a sputum specimen
    • brush teeth
    • use mouth wash
  65. imaging studies that can be done to diagnosis respiratory illness/disease
    • XR
    • CT
    • MRI
  66. what procedure may be done if a pt has accumulation of pleural fluid?
  67. what is a thoracentesis?
    aspiration of fluid or air from the pleural space
  68. A thoracentesis may be preformed for ________ and/or ________ reasons.
    • diagnostic
    • therapeutic
  69. purposes of a thoracentesis
    • removal of fluid and air from pleuaral cavity
    • aspiration of pleural fluids for analysis
    • pleural biopsy
    • instillation of meds into pleural space
  70. what studies are ran on pleural fluid when biopsy done?
    • gram stain C&S
    • acid-fast staining and culture
    • differential cell count
    • cytology
    • pH
    • specific gravity
    • total protein
    • lactic dehydrogenase
  71. what measure can be taken when a thoracentesis is performed to lower the rate of complications?
    perform under ultrasound guidance
  72. is a thoracentesis a sterile procedure?
  73. True or False.  A nurse does not have to obtain a consent for a thoracentesis.
  74. What is the optimal position to place a pt in for a thoracentesis?
    upright, sitting on edge of bed w/ feet supported and arms on padded side table
  75. 2 other options for positioning for thoracentesis
    1.  straddling chair w/ arms and head resing on the back of the chair

    2.  lying on unaffected side w/ the HOB elevated 30-45* if unable to assume a sitting position
  76. rationale for upright, sitting on edge of bed and leaned over table position in thoracentesis
    upright position facilitates the removal of fluid that usually localizes at the base of the thorax

    a position of comfort helps the pt to relax
  77. endoscopic procedures include: __________ and _________.
    • bronchoscopy
    • thorascopy
  78. what is a bronchoscopy?
    the direct inspection and examination of the larynx, trachea, and bronchi through either a flexible fiberoptic bronchoscope or a rigid bronchoscope
  79. which type of bronchoscope is used more frequently in current practice?
    flexible fiberoptic bronchoscope
Card Set
Respiratory lecture
Sheri's respiratory lecture