Airway Management - Anatomy & Physiology Flashcards
The upper airway consists of all anatomic airway structures above the level of the ___
Vocal cords
Upper airway structures
- Nose
- Mouth
- Jaw
- Oral cavity
- Pharynx
- Larynx
The major function of the upper airway
To warm, filter, and humidify air as it enters the body through thr mouth and nose
A muscular tube that extends from the nose and mouth to the level of the esophagus and trachea
Pharynx (throat)
The pharynx is composed of ___
- Nasopharynx
- Oropharynx
- Laryngopharynx
The laryngopharynx is also called the ___
Hypopharynx
Lowest portion of the pharynx
Laryngopharynx
At the base, the laryngopharynx ___
Splits into two lumens, the larynx (and ultimately the trachea) anteriorly and the esophagus posteriorly
The nasopharynx is lined with ___
A ciliated mucous membrane that keeps contaminants such as dust out of the respiratory tract
The mucous membranes in the nose ___ air as it enters the body, in addition to filtering it
Warm and humidify
After air enters the nose, it passes into the ___
Nasopharynx
Forms the posterior portion of the oral cavity
Oropharynx
The oral cavity is bordered by ___
- Superiorly by the hard and soft palates
- Laterally by the cheeks
- Inferiorly by the tongue
Helps separate the digestive system from the respiratory system
Epiglottis
The epiglottis is located ___
Superior to the larynx
When swallowing occurs, the larynx is ___ and the epiglottis ___
- Elevated
- Folds over the glottis to prevent aspiration of contents into the trachea
The larynx is a complex structure formed by ___
Many independent cartilaginous structures
The thyroid cartilage is ___
A shield-shaped structure formed by two plates that join in a V shape anteriorly to form the laryngeal prominence known as the Adam’s apple
The cricoid cartilage, or cricoid ring, lies ___
Inferiorly to the thyroid cartilage
Forms the lowest portion of the larynx
Cricoid cartilage
First ring of the trachea
Cricoid cartilage
The only lower airway structure that forms a complete ring
Cricoid cartilage
The elastic tissue that connects the thyroid cartilage superiorly to the cricoid ring inferiorly
Cricothyroid membrane
The space between the vocal cords and the narrowest portion of the adult’s airway
Glottis
The glottis is also called the ___
Glottic opening
The lateral borders of the glottis are the ___
Vocal cords
These white bands of thin muscle tissue are partially separated at rest and serve as the primary center for speech production
Vocal cords
Vocal cords defense reflexes
Protect the lower airway, causing a spasmodic closure to the lower airway to prevent substances from entering the trachea
The function of the lower airway
Deliver oxygen to the alveoli
External boundaries of the lower airway
4th cervical vertebra and the xiphoid process
Internally the lower airway spans the ___
Glottis to the pulmonary capillary membrane
Conduit for air entry into the lungs
Trachea (windpipe)
The trachea is a ___
Tubular structure about 4 to 5 inches long and consists of C-shaped cartilaginous rings
The trachea begins ___ and descends ___
- Directly below the cricoid cartilage
- Anteriorly down the midline of the neck into the thoracic cavity
Once in the thoracic cavity, the trachea ___
Divides at the level of the carina into the two main stem bronchi (right & left)
The hollow bronchi are supported by ___ and distribute ___
- Cartilage
- Air into the right and left lungs
Infants and small children have a proportionately larger occiput (posterior portion of the cranium), which causes ___. To mitigate this ___
- The neck to flex, moving the head forward and backward when supine
- Place a folded towel under the child’s shoulders to maintain a neutral position of the head
Children have a proportionately smaller mandible and a proportionately larger tongue. Both factors increase the incidence of ___
Airway obstruction
The child’s epiglottis is more ___ than an adult’s
Floppy and omega-shaped
In general, the infant’s and child’s airway is ___ at all levels
Smaller and narrower
The larynx of a child lies ___
More superior and anterior than that of an adult
The larynx of a child is ___ shaped due to the ___
- Funnel
- Narrow, underdeveloped cricoid cartilage
In children younger than 8 years, the narrowest portion of the airway is at the ___
Cricoid ring
Children do not have well-developed chest musculature, and their ribs are softer and more pliable than those of an adult. As a result ___
The thoracic cavity cannot optimally contribute to lung expansion, and children rely heavily on the diaphragm for breathing
Children and infants are commonly referred to as ___ breathers
Belly
The lungs consist of the entire mass of tissue that includes the ___
Smaller bronchi, bronchioles, and alveoli
Thin serous membranes that cover the lungs and line the thoracic cavity
Pleurae
The visceral pleura covers the ___
Outer surface of the lung tissue
The parietal pleura lines the ___
Inside of the thoracic cavity
A small amount of ___ is found between the two pleural layers and serves as a ___
- Fluid
- Lubricant to prevent friction during breathing
On entering the lungs, each bronchus divides into ___, which in turn subdivide into ___
- Increasingly smaller bronchi
- Bronchioles
The bronchioles are ___
Think hollow tubes made of smooth muscle
The tone of the smooth muscles of the bronchioles allows them to ___
Dilate or constrict in response to various stimuli
The smaller bronchioles branch into ___ that end at ___
- Alveolar ducts
- Alveolar sacs
Millions of thin-walled, balloon-like sacs that serve as the functional site for the exchange of oxygen and carbon dioxide
The alveoli
Surrounding each alveolar sac is an ___
Intricate bed of blood vessels known as pulmonary capillaries
Muscles between the ribs that facilitate normal breathing with the diaphragm
Intercostal muscles
Space between the lungs
Mediastinum
The mediastinum is surrounded by ___
Tough connective tissue
The mediastinum effectively separates the ___
Right and left lungs spaces
The phrenic nerves originate from ___
The third, fourth, and fifth cervical nerves
What do the phrenic nerves do?
Innervate the diaphragm muscle, allowing it to contract
Contraction of the diaphragm occurs in a ___ direction
Downward
The physical act of moving air into and out of the lungs
Ventilation
The process of loading oxygen molecules onto hemoglobin molecules in the bloodstream
Oxygenation
The actual exchange of oxygen and CO2 in the alveoli as well as the tissues of the body
Respiration
The active muscular part of breathing
Inhalation
What causes air to move into the lungs
Negative pressure from diaphragm contracting downwards, and intercostal muscles contracting, lifting the ribs up and out
Why can’t the lungs move on their own?
They contain no muscle tissue
Describes the amount of gas in air or dissolved in fluid, such as blood
Partial pressure
Partial pressure is measured in ___
mm/Hg
The partial pressure of oxygen in air within the alveoli is ___
104 mm/Hg
CO2 entering the alveoli from the blood causes a partial pressure of ___
40 mm/Hg
Deoxygenated arterial blood from the right side of the heart has lower levels of ___ than ___. The body attempts to ___
- Oxygen
- CO2
- Equalize the two, resulting in oxygen diffusion across the membrane into the blood and CO2 diffusion in the opposite direction
The air pressure outside the body is normally ___ than the air pressure within the thorax
Higher
Average tidal volume for an adult man
500 mL
The portion of the tidal volume that does not reach alveoli and thus does not participate in gas exchange
Dead space
The amount of air (in mL) that is moved into or out of the lungs during one breath
Tidal volume
The air that remains in the lungs after maximal expiration
Residual volume
The volume of air that reaches the alveoli
Alveolar ventilation
How to calculate alveolar ventilation
Subtract the amount of dead space air from the tidal volume
The volume of air moved through the lungs in 1 minute
Minute volume
How to calculate minute volume
Multiply tidal volume and respiratory rate
The volume of air moved through the lungs in 1 minute minus the dead space
Alveolar minute volume
How to calculate alveolar minute volume
Multiply tidal volume (minus dead space) and respiratory rate
The amount of air that can be forcibly expelled from the lungs after breathing in as deeply as possible
Vital capacity
Exhalation does not normally require ___
Muscular effort
Exhalation is a ___ process
Passive
Clearing the airway means ___
Removing obstructing material, tissue, or fluids from the nose, mouth, and throat
Maintaining an airway means ___
Keeping the airway patent
Open, free of obstructions
Patent
Tissues and cells of the body do not get enough oxygen
Hypoxia
The drive to breathe is based on ___
pH changes in the blood and CSF
When CO2 levels in the blood increase, the pH of CSF ___
Decreases
When the pH of CSF decreases ___
A message is sent to the respiratory centers in the brain, which stimulates breathing
COPD
Chronic Obstructive Pulmonary Disease
Patients with COPD have difficulty eliminating ___
CO2 through exhalation
In patients with COPD, the body uses ___ to control breathing
A backup system called the hypoxic drive
The hypoxic drive is based on ___
Levels of oxygen dissolved in plasma
Patients who are breathing inadequately will show varying signs and symptoms of ___
Hypoxia
The onset and degree of tissue damage caused by hypoxia often depend on the ___
Quality of the ventilations
Early signs of hypoxia
- Restlessness
- Irritability
- Apprehension
- Tachycardia
- Anxiety
Late signs of hypoxia
- Mental status changes
- Thready pulse
- Cyanosis
Conscious hypoxia patients will complain of ___
Shortness of breath and may not be able to talk in complete sentences
Shortness of breath
Dyspnea
The best time to give a patient oxygen
Before signs and symptoms of hypoxia appear
Difference between hypoxemia and hypoxia
Hypoxemia: Low level of oxygen in arterial blood
Hypoxia: Low level of oxygen at the cellular level
Uncorrected hypoxemia will lead to ___
Hypoxia
Oxygenation requires that the air used for ventilation contains an ___
Adequate percentage of oxygen
CO affinity for hemoglobin vs oxygen
250 times more
Cellular respiration
Metabolism
During metabolism, each cell ___
Combines nutrients and oxygen and produces energy and waste products
Energy produced in the cells
Adenosine triphosphate
Waste products of cells are primarily ___
Water and CO2
The process of breathing fresh air into the respiratory system and exchanging oxygen and CO2 between the alveoli and the blood in the pulmonary capillaries
External respiration (pulmonary respiration)
Makeup of fresh air
21% oxygen
78% nitrogen
0.3% CO2
As the fresh air reaches the alveoli, it comes in contact with a fluid called ___
Surfactant
Reduces surface tension within the alveoli and keeps them expanded, making it easier for the gas exchange between oxygen and CO2 to occur
Surfactant
Although adequate ventilation is necessary for external respiration to occur, it does not guarantee that ___
External respiration is being achieved
Under normal conditions, ___ of the hemoglobin receptor sites contain oxygen
96% to 100%
The exchange of oxygen and CO2 between the systemic circulatory system and the cells of the body is called ___
Internal respiration
To deliver sufficient oxygen to the tissues of the body, adequate ___ must occur
Ventilation and perfusion
With aerobic metabolism, cells convert ___ into energy
Glucose
