47 terms

Chapter 13 Altered Ventilation and Diffusion

Exam 2
conducting airways
Move air into lungs
Warm and humidify air
Trap inhaled particles
respiratory airways
Gas is exchanged with the blood
Involves both acquiring oxygen (inspiration) and removing carbon dioxide (expiration) from the blood
Neuronal impulses are directed by lung receptors, which map the current state of breathing and lung function
Uses the intercostal muscles, diaphragm, and sternocleidomastoid muscles
Breathing in to acquire oxygen

Unidirectional from high pressure to low pressure.

Chest cavity size changes to alter the pressure gradient
Removing carbon dioxide out of the body through the lungs

The diaphragm and external intercostal muscles relax

Lungs compress and increase the pressure inside the airways
Oxygen and carbon dioxide are exchanged at alveolar capillary junctions

Two major process occur:
Oxygen is trying to get to all the cells
Carbon dioxide is trying to escape the body through the lungs
gas exchange
Oxygen moves from alveolar air into blood
Carbon dioxide moves from blood into alveolar air
partial pressure
The collision of oxygen and carbon dioxide creates pressure
blood gases- oxygen
Dissolved oxygen = PaO2 or PO2
Normal value >80 mm Hg
Oxygen bound to hemoglobin = oxyhemoglobin
Normal value 95% to 97% saturation
Below 90% needs oxygen
impaired ventilation
A problem of blocking airflow in and out of the lungs
Two major mechanisms implicated:
Compression or narrowing of the airways
Disruption of the neuronal transmissions needed to stimulate the mechanics of the airways
ventilation perfusion mismatching
Blood goes to parts of the lung that do not have oxygen to give it
Blood does not go to parts of the lung that have oxygen
Perfusion without ventilation is a blocked airway.
Ventilation without perfusion is a blocked capillary
impaired diffusion
Restricted transfer of oxygen and/or carbon dioxide across the alveolar capillary junction
Dependent upon:
solubility and partial pressure of the gas
surface area and thickness of the membrane
PO2 <60 mm Hg
Impaired function of vital centers
Agitated or combative behavior, euphoria, impaired judgment, convulsions, delirium, stupor, coma
Retinal hemorrhage
Hypotension and bradycardia
Activation of compensatory mechanisms
Sympathetic system activation
Measured with arterial blood gas
lack of oxygen at the tissue level. O2 Sat
PCO2 >50 mm Hg
Respiratory acidosis
Increased respiration
Decreased nerve firing
Carbon dioxide narcosis
Disorientation, somnolence, coma
Decreased muscle contraction
Headache; conjunctival hyperemia; warm, flushed skin
treating impaired ventilation and diffusion
Remove obstruction and restore physical integrity of airways, lung tissues
Decrease inflammation and mucus; treat infection
Supplemental oxygen
Mechanical ventilation
pneumonia patho
Infectious process
Respiratory droplet spread
Causes inflammation of the lungs
Occurs commonly in the bronchioles, interstitial lung tissue and/or the alveoli
Products of inflammation accumulate and cause consolidation
pneumonia manifestations
Sudden onset of fever
Sputum production
Loss of appetite
Pleuritic pain
Crackles in lungs
pneumonia diagnostic criteria
History and physical examination
Complete blood cell count
Chest X-ray
Thoracic CT scan
pneumonia treatment
Restore optimal ventilation and diffusion
Identify pathogen and target with appropriate pharmacologic treatment
Supplemental oxygen
TB patho
Mycobacterium tuberculosis

Airborne droplet nuclei travel directly to the terminal bronchioles and alveoli of the lung

Inflammatory and immune responses
Containment- asymptomatic, granuloma may form
Multiplication- progressive primary TB
tb manifestations
Many of those infected are symptomatic
In the presence of chronic inflammation:
Weight loss
Low-grade fever
Possibly night sweats
tb diagnostic criteria
Tuberculin skin tests
Chest X-ray
Sputum culture
Sputum nucleic acid amplification
emphysema pathophysiology
Irreversible enlargement of the air spaces beyond terminal bronchioles
destruction of the alveolar walls
obstruction of airflow
Chronic smoking most often implicated
emphysema clinical manifestations
Persistent cough
Barrel chest
Pursed lip breathing
emphysema diagnostic
History and physical examination
Pulmonary function tests
Chest x-ray
emphysema treatment
Maintain optimal lung function in order to allow the individual to perform the desired activities of daily life
Smoking cessation
Pharmacologic therapy
Lung volume reduction or transplant
chronic bronchitis patho
Persistent, productive cough lasting three months or greater, for two or more consecutive years
Result of:
Chronic inflammation and edema of the airways
Hyperplasia of the bronchial mucous glands and smooth muscles
Destruction of cilia
Squamous cell metaplasia
Bronchial wall thickening and development of fibrosis
chronic bronchitis manifestations
Purulent sputum
Adventitious lung sounds
chronic bronchitis diagnostic criteria
History and physical examination
Arterial blood gases
Pulmonary function tests
Pulse oximetry
Sputum analysis
chronic bronchitis treatment
Smoking cessation
Pulmonary rehabilitation
Pharmacologic therapy
Supplemental oxygen
asthma patho
Intermittent or persistent airway obstruction due to:
Bronchial hyperresponsiveness
Chronic inflammation
Excess mucous production
asthma manifestations
Wheezing and tachypnea
Dyspnea and coughing
Chest tightness
Excessive sputum production
asthma diagnostic criteria
History and physical examination
Pulmonary function tests
Laboratory studies
Chest x-ray
asthma treatment
Monitor lung function
Control environmental triggers
Pharmacologic therapy
Patient and family education; action plan
cystic fibrosis patho
Autosomal recessive disorder of electrolyte and water transport affecting certain epithelial cells (respiratory, digestive, and reproductive lining)

Mutation of the CF gene

Associated with mucus plugging, inflammation, and infection in the lungs; also affects other body systems

Respiratory failure is most common cause of death
cf manifestations


cf diagnostic criteria
History and physical examination
Sweat test
Genetic testing
Chest x-ray
Sputum analysis
cf treatment
Chest physiotherapy
Pharmacologic treatment
Lung transplant
Optimal nutrition
Pancreatic enzymes
ARDS patho
Lung injury to respiratory distress within 24-48 hours
Severe acute inflammation and pulmonary edema without evidence of fluid overload or impaired cardiac function
Mortality rate 30%-40% from multi-system organ failure in those untreated
ARDS clinical manifestations
Crackles due to fluid accumulation
Restlessness, anxiety
ARDS diagnostic criteria
History and physical examination
Laboratory studies
Imaging studies
ARDS treatment
Remove causative factors
Administration of 100% oxygen
Mechanical ventilation
pleural disorders decreased ventilation
Parietal pleura lines the thoracic wall and superior aspect of the diaphragm
Visceral pleura covers the lung
Pleural cavity or space between the two layers contains a thin layer of serous fluid
Air enters the pleural cavity
Air takes up space, restricting lung expansion
Partial or complete collapse of the affected lung
Spontaneous: an air-filled blister on the lung ruptures
Traumatic: air enters through chest injuries
Tension: air enters pleural cavity through the wound on inhalation but cannot leave on exhalation
Open: air enters pleural cavity through the wound on inhalation and leaves on exhalation
open pneumothorax
lung collapse but air can still go in and out
tension pneumothorax
lung collase and air can go in but not out, not allowing the lung to expand.