Respiratory Pathologies ( WK1- Ch 15 )

Question 1

Define hypoxia and the physiological boundaries that constitute it.

Answer 1

• reduced blood oxygen ( PaO2 < 80 mmHg or O2 sat. <90% )

Question 2

Define hypercapnea and the physiological boundaries that constitute it.

Answer 2

-increased blood carbon dioxide content ( PaCO2 >45mmHg )

Question 3

Your 73-year-old female patient has a severe lower lobe bacterial pneumonia with dyspnea and fever/chills. She is admitted to the acute care hospital where you are seeing her.

Based on what you know about her pneumonia, if the infection spread to the pleural space, removal of excess fluid would reveal:

Answer 3

Pyothorax

Question 4

Define bronchiectasis

Answer 4

a necrotizing infection of the bronchi that destroys muscular wall and elastic components of the bronchus

-patients often have “fecal” breath due to necrotizing tissue

Question 5

Neonatal Respiratory Distress Syndrome - Hyaline Membrane Disease is caused by prematurity of:

Answer 5

<37 weeks

Question 6

What two disease states fall under the category of chronic obstructive pulmonary disorder ?

Answer 6

chronic bronchitis, and emphysema

Question 7

80-90% of all emphysema is caused by:

Answer 7

smoking

Question 8

pathogenesis of __________ is the destruction of elastic fibers surrounding the alveoli

Answer 8

emphysema

Question 9

How is chronic bronchitis defined ?

Answer 9

a productive cough for at least 3 months in a row for 2 consecutive years.

Question 10

Pathogenesis of ___________ is excess mucous secretions due to hyperplasia of mucous glands

Answer 10

Chronic Bronchitis

Question 11

What are the common signs of COPD ?

Answer 11

Orthopnea, wheezing, chronic cough, peripheral cyanosis, pursed-lip breathing, use of accessory muscles of respiration, shortness of breath, dyspnea on exertion, barrel chest, prolonged expiratory period, elbow changes

Question 12

People with restrictive lung disease have trouble getting air… ( in or out? )

Answer 12

-IN
- any condition that prevents lungs from getting air in can be considered RLD; may include neurologic or neuromuscular disorders such as GBS, myasthenia gravis or mechanical conditions such as kyphosis and scoliosis
- scar tissue replaces lung tissue like in sarcoidosis and pneumoconiosis

Question 13

With restrictive lung disease FVC is _______

Answer 13

reduced

Question 14

Air in the pleural space is known as:

Answer 14

pneumothorax

Question 15

Infection from lung that has spread into the pleural cavity is known as:

Answer 15

pleuritis

Question 16

What is ARDS, describe its incidence, risk factors, and pathogenesis

Answer 16

• Adult Respiratory Distress Syndrome is a form of acute respiratory failure after a systemic or pulmonary insult
• Incidence of about 200,000 and kills 50,000 per year.
  -Risk factors include, age, sepsis, pneumonia, aspiratio, trauma, pancreatitis, blood transfusions, and smoke inhalation
• Results from three primary issues; acute injury to alveolar-capillary membrane, inflammation, and increase permeability of the alveolar-capillary membrane leading to pulmonary edema. The alveolar–capillary membrane becomes injured, causing protein-rich fluid to leak into the interstitium. When this volume exceeds the ability of the lymphatics to remove it, the edema moves into the airspaces
  impacting gas exchange. Second, neutrophils become activated and begin to erode the basement membrane of the alveoli. Moreover, neutrophils release mediators that are proinflammatory
  and contribute to cell apoptosis. Finally, here is also damage to type II alveolar cells which produce surfactant. Reduction of surfactant contributes to alveolar collapse, increased compliance, and impaired
  gas exchange. Type II cells also have a role in repairing the epithelium, so when destroyed, remodeling can be affected and fibrosis or scarring ensues, adding to the problem.
• In short, ARDS leads to endothelial damage of the alveoli.

Question 17

What is SIDS, its incidence and ways to combat it.

Answer 17

-SIDS stands for Sudden infant death syndrome
- 2,000 infants die each year from SIDS
- should be bed on their back with a pacifier to allow for better ventilation
- the proposed mechanism is that the medullary cardiorespiratory center is immature
- studies show that a long QT segment > 35msec is linked to increased risk of SIDS

Question 18

What 3 things happen during an asthmatic attack; incidence ?; precipitating factors; pathogenisis; signs and symptoms; and treatments

Answer 18

• bronchospasm, inflammation of the bronchioles, excess secretion of mucous into airways
• affects 25.7 million americans; it is an acute obstructive disorder
• can be precipitated by infections, exercise, occupational, drug-induced ( bronchoconstriction from beta agonists), air pollution, and emotional factors
• pathogenisis ( extrinsic) : exposure to an allergen, allergen binds to IgE on mast cells, mast cells degranulate releasing histamine, leukotrienes, and eosinophil chemotactic factors, which lead to edema, mucous secretion, and bronchoconstriction.
• Signs and symptoms: episodes of dyspnea, prolonged expiration with decreased FEV1/FVC, cough or sputum production, skin retraction, abnormal fatigue, tickle in the back of the throat, wheezing, nostril flaring
• Treatment: anti-inflammatroy corticosteroids, bronchodilators, oral steroids

Question 19

What are the causes, pathogenesis, signs and symptoms, of emphysema

Answer 19

• causes : mainly smoking ( 80-90%), other 10% due to hereditary alpha1 antitrypsin deficiency

-pathogenesis: inhibition of alpha 1 antitrypsin ( because it inhibits serine elastase) so when serine elastase is allowed to fucntion it leads to destruction of elastic fibers surrounding the alveoli which compromises its structure, the result is lost of elasticity of lung tissue causing narrowing or collapse of bronchioles so that inspired air becomes trapped in the lungs.

• signs/ symptoms: decreased forced expiratory volume/ forced vital capacity, shortness of breath, dyspnea on exertion, orthopnea, wheezing, increased RR, peripheral cyanosis, barrel chest, weight loss, use of accessory respiration muscles; often accompanied by chronic bronchitis

treatment: medications, supplemental oxygen, surgery, pulmonary rehab

Question 20

Define Pneumonia; describe its pathogenesis; and signs/symptoms

Answer 20

• Infection of the lungs can be bacterial or viral; leads to an inflammatory process
• In the compromised person, the normal release
  of biochemical mediators by alveolar macrophages as part
  of the inflammatory response does not eliminate invading
  pathogens. The multiplying microorganisms release
  damaging toxins stimulating full-scale inflammatory and
  immune responses with damaging side effects.
• Type II surfactant producing cells can be damaged

-sudden sharp pleuritic chest pain aggravated by movement; dypsnea; tachypnea; cyanosis; headaches; fever and chills; fatigue; hacking productive cough

Question 21

Define cystic fibrosis; give its pathogenesis, signs/symptoms

Answer 21

• CF is an inherited disorder of ion transport (sodium and chloride) in the exocrine glands affecting the hepatic, digestive, reproductive (the vas deferens is functionally disrupted in nearly all cases; decreased fertility in both sexes), and respiratory systems (Fig. 15-15). The basic genetic defect predisposes to chronic bacterial airway infections, and almost all persons develop obstructive lung disease associated with chronic infection that leads to progressive loss of pulmonary function.
• tachypnea, sustained chronic cough, barrel chest, use of accessory muscles of respiration, cyanosis and digital clubbing, pneumothorax, hemoptysis, RT heart failure

Question 22

What are the early symptoms of lung cancer

Answer 22

hemoptysis, dyspnea, wheezing, seziures, recurrent pneumonia, sudden weight loss

Question 23

What are the signs and symptoms of respiratory acidosis and what are the values corresponding to compensated and uncompensated acidosis ?

Answer 23

• CO2+ H2O –> H2CO3- -> H+ + CO3-
• decrease ventilation, confusion, sleepiness and unconsciousness, diaphoresis ( excessive sweating) , shallow rapid breathing, restlessness, cyanosis
• Uncompensated: pH <7.35, PaCO2 >45, HCO3 normal
• Compensated: pH normal, PaCO2 >45, HCO3 >26

Question 24

What are the signs and symptoms of respiratory alkalosis and what are the values corresponding to compensated and uncompensated alkalosis ?

Answer 24

• CO2+ H2O –> H2CO3- -> H+ + CO3-
• Lightheadedness, dizziness, numbness and tingling of face fingers and toes, syncope
• Uncompensated: pH >7.45, PaCO2 <35, HCO3 normal
• Compensated: pH normal, PaCO2 <35, HCO3 <22

Question 25

What are the normal pH, PaCO2, and HCO3 values of arterial blood ?

Answer 25

pH: 7.35-7.45
PaCO2: 35-45
HCO3: 22-26