Airway Management And Ventilation Flashcards
What is the sellick maneuver?
Compressing the cricoid cartilage that occludes the esophagus resulting in reduced gastric distention during ventilation and placement of an endotracheal tube.
What is the total lung capacity in an average adult male?
6L
What is the normal tidal volume in an adult male?
5-7 mL/kg
Approximately 500mL
What is the normal tidal volume for pediatric patients?
6-8 mL/kg
What is alveolar air?
The amount of gas that reaches the alveoli with each breath.
What is the formula for alveolar air?
Tidal volume➖dead space volume
It is approximately 350mL
What are the two phases of ventilation?
Inspiration
Expiration
What is the nervous system mechanism that terminates inhalation and prevents lung over-expansion?
Hering-Breuer reflex
What is external (pulmonary) respiration?
Exchange of gases between the lungs and the blood cells in the pulmonary capillaries
What is internal (cellular) respiration?
Exchange of gases between blood cells and tissues
What is a minute volume?
The amount of air moved in and out of the lungs in one minute
(Tidal volume ➖ dead space volume)✖️respiratory rate
The amount of air that can be forced from the lungs in a single forced exhalation is called what?
Functional reserve capacity
What is residual volume?
The air that remains after maximal expiration
What is the residual volume of an average male?
1200 mL
What is inspiratory reserve volume?
The amount of air you can inhale after a normal inhalation
What are the two motor nerves of respiration?
Phrenic nerves
Intercostal nerves
What do the phrenic nerves do?
Innervates the diaphragm
What do the intercostal nerves do?
Innervates the external intercostal muscles (muscles between the ribs)
What is the percentage of oxygen that makes up hemoglobin?
97%
What is the remaining oxygen that is dissolved in plasma called?
Partial pressure of oxygen (PaO2 , PO2)
What is a byproduct of cellular respiration?
Carbon dioxide
What are three conditions that decrease the surface area of the alveoli?
COPD
Pneumonia
Pulmonary edema
What is intrapulmonary shunting?
If the alveoli are not functional, carbon dioxide and oxygen will not be allowed to diffuse. Therefore the blood will bypass the alveoli and will return to the left side of the heart and in an unoxygenated state
What is Dalton’s law?
The total pressure exerted equals the sum of the partial pressures of the components of that gas, or the pressure exerted by a specific atmospheric gas
What is the total pressure of air at sea level?
About 760 mm Hg (760 torr)
What connects the medulla and the respiratory muscles?
The vagus nerve
What three things does the medullary respiratory centers control?
Rate
Depth
Rhythm
…Of breathing
What is the secondary control center of respiration if the medulla fails to initiate respiration?
The apneustic center of the pons
How does the apneustic center influence the respiratory rate?
By increasing the number of inspirations per minute
What does the pneumotaxic center inhibit?
Inhibits the influence of inspiration
Where are peripheral chemoreceptors that measure the amount of CO2 (Paco2) and arterial blood located?
The carotid bodies and the aortic arch
What two nerves send signals to the respiratory center if CO2 levels change?
Glossopharyngeal nerve (9th cranial nerve) Vagus nerve (10th cranial nerve)
What do central chemoreceptors constantly monitor?
The pH of cerebrospinal fluid
Where are central chemoreceptors located?
Adjacent to the respiratory centers in the medulla
What is the average rate of respirations for an adult?
12-20 breaths/min
What is the average of the respiration rate for children?
15-30 breaths/min
What is the average respiration rate for infants?
25-50 breaths/min
What are four causes of respiratory distress?
Upper/lower airway obstruction
Inadequate ventilation
Impairment of respiratory muscles
Impairment of nervous system
What is orthopnea?
Positional dyspnea (difficulty breathing while supine)
What is pulsus paradoxus?
When the systolic blood pressure drops more than 10 mmHg with inspiration and/or a change in quality or even disappearance of a pulse
What two patients generally have pulsus paradoxus?
Patients with decompensating COPD
Severe pericardial tamponade
An increase in intrathoracic pressure could indicate what?
Pulsus paradoxus
What is atelectasis?
A condition of airless or collapsed alveoli
What are Cheyne-Stokes respirations?
A gradual increase of rate and tidal volume followed by a gradual decrease
What are Cheyne-Stokes respirations associated with?
Brain stem insult
What are Kussmaul respirations?
Deep gasping respirations
What two things are Kussmaul respirations associated with commonly?
Common diabetic coma and keto acidosis
What are Biot respirations?
Irregular pattern, rate, and volume with intermittent periods of apnea
What are Biot respirations commonly caused by?
Increased intracranial pressure
What is central neurogenic hyperventilation?
Deep, rapid respirations similar to Kussmaul respirations
What’s is central neurogenic hyperventilation commonly caused by?
Increased intracranial pressure
What are agonal respirations?
Slow, shallow, irregular respirations or occasional gasping breaths
What are agonal respirations a result of?
Results from brain anoxia. The heart has stopped but the brain continues to send signals to the muscles of respiration
What is hyperkalemia?
High potassium levels
What three things does atelectasis cause?
Pulmonary shunting
Ventilation perfusion mismatching
Possibly hypoxemia