SF3 Exam 2 Control Of Respiration Flashcards
What are central chemoreceptors sensitive to?
Where are they located?
CO2 fluctuation
In the Brainstem on the other side of the blood brain barrier.
Where are the peripheral chemoreceptors located?
What variables effect them?
Located in the neck and aortic arch
Arterial H+
PCO2
PO2
What is the most important controller of ventilation in central chemoreceptors?
How does this variable cause this?
PaCO2
CO2 can enter the CSF. Here it binds with water and results in H+ and bicarb formation
CSF lacks hemoglobin, so the H+ causes an increased rate of breathing due to the initial lowering of pH.
What does hypoxia activate?
Can hypoxia be adapted to through this mechanism?
Peripheral chemoreceptors
Adaptation cannot be achieved in peripheral receptors for hypoxia
What is the most powerful stimulus of respiration? Which type of receptor is this?
Most powerful is pH
Peripheral
How does hypercapnia effect hypoxia?
Hypercapnia is increased PCO2.
This causes an increased effect of hypoxia.
Since both of these are in effect, the PO2 being low and the CO2 being high, both the CENTRAL and PERIPHERAL chemoreceptors kick in, increasing ventilation.
What sustains respiratory drive at high elevations?
Arterial PaO2
You have a PaO2 of 45mmHg and a PaCO2 of 62mmHg. What receptor(s) is/are being activated and by which piece of information?
Peripheral—— O2 is below 60mmHg
Central—— CO2 is above 45mmHg
What parameters activate peripheral and central chemoreceptors in terms of PaCO2 and PaO2
PaO2<60 activates peripheral
PaCO2>45 activates central
The phrenic nerves effect?
Inhalation
If a person damages C7, what would happen during respiration?
Chest wall function will be impaired
Intercostal muscles are innervated at this level
Dorsal Respiratory Groups (DRGs) are made of what type of neuron?
What do DRGs control?
Inspiratory neurons
They control your basic rhythm of breathing.
What do your Ventral Respiratory Groups (VRGs) control?
When are these used?
They control you upper airway muscles
They are recruited during exercise.
Where are the DRG and VRG located?
Medulla
Where is the Apneustic center?
Pons
What is apneustic breathing?
When is this shown to occur?
Inspiration holds in the cycle
When the apneustic center, pneumotaxic center, and vagus nerve are removed
What is wrong in Congenital Central Hypoventilation Syndrome (CCHS)?
What is required to treat this?
Central pattern generator is inoperative
Insensitivity to CO2, O2, and pH
Respiration is not automatically controlled.
They must use a mechanical ventilator.
What effect does alcohol, opiates, barbiturates, and anesthetics have on breathing?
They dampen normal response to CO2 increased and cause respiratory failure.
What do cocaine, amphetamine, and caffeine cause?
They cause an increase in respiratory drive
How does mild hypothermia effect ventilation?
What about deep hypothermia?
Mild increases ventilation due to an increased sympathetic nervous system.
Deep causes depression of ventilation due to lowered neural activity
What patients typically display the Cheyenne-Stokes Breathing pattern?
What appears first in the pattern?
cardiac failure or brain damage
PCO2 of pulmonary blood increases then the PCO2 of respiratory neurons.
Fast lines followed by apnea. (Hyperventilation occurs/ “waxing and waning of ventilation”
Biot’s respiration occurs in which patients?
What is it characterized by?
Meningitis and cerebral circulation disorders
Hyperapnea where there is an increased depth of respiration amplitude followed by apnea.
Central sleep apnea
Airflow matches thoracic effort.
This is a normal cycle with absent airflow of 10 second cycles inserted.
Obstructive Sleep apnea
Thoracic effort constantly works, but an upper airway obstruction (by fat or other) causes pharyngeal muscles to not contract.
This leads to gaps in airflow
Kussmaul’s respiration.
Hyperventilation
Deep and labored
Kidney failure/ diabetic coma/ high acidosis
repetitive quick sharp peaks
If a person comes in with high PCO2 and low PO2 and they are in distress, what should you do?
The CO2 will fix itself.
You shouldn’t give 100% oxygen. The patient will stop breathing. You need to watch the patient and use a lower mixture of oxygen to start with them.
