RSPT 2255 Critical Care Monitoring Unit
1 Exam Study Guide
How is Compliance (CL) measured? - ANSWER CL = Change in Volume / Change
in Pressure
Compliance is a measure of the dispensability of the lungs:
- CL = The compliance of the lungs/thorax.
V = The change in volume (L).
P = The change in pressure (cm).
Static Compliance (Cst) - ANSWER The change in Volume in the respiratory
system for a given unit of applied pressure at the end of inspiration but before
exhalation.
Plateau Pressure (Pplat) - ANSWER A stable pressure measured at the end of an
inspiratory hold.
Airflow Resistance (Raw) - ANSWER The opposition to flow caused by frictional
forces and expressed as the ratio of driving pressure to the rate of gas flow.
Oxygenation Failure - ANSWER Severe Hypoxemia due to any condition.
Dead Space Ventilation - ANSWER The volume of a breath that does not
participate in gas exchange. It is ventilation without perfusion.
Pressure-Volume Slope - ANSWER The rate of change observed in a pressure-
volume plot of a breath.
Dynamic Compliance - ANSWER The change in volume for a given unit of applied
pressure when gas is moving in the respiratory system.
Ventilation-Perfusion Mismatch - ANSWER This occurs when the ideal
proportion of ventilation in a lung area is either greater or lesser than the
amount of blood flow.
Peak Inspiratory Pressure (PIP) - ANSWER The largest pressure attained during
inspiration.
Ventilatory Failure - ANSWER Occurs when the patient's minute alveolar
ventilation cannot keep up with the metabolic rate or CO2 production. O2 failure
, usually follows when the cardiopulmonary system cannot provide adequate O2
needed for metabolism.
Hypoxemia - ANSWER A lower than normal level of O2 in the blood.
Intrapulmonary Shunting - ANSWER A condition in which blood flowing through
a lung area is exposed to under-ventilated or unventilated alveoli, resulting in
significant hypoxemia.
Hypoxia - ANSWER A lack of sufficient O2 in the tissues or organs.
What causes Hypoventilation (Vent Failure) and the clinical presentation? -
ANSWER Causes:
Spinal Cord Injury
Neuromuscular Disorder
Overdose of Analgesics or Sedatives
Severe Airway Obstruction
Central Sleep Apnea
Clinical Presentation:
Reduced Minute Ventilation
Hypercapnea
One of the conditions leading to vent failure is Venous Admixture.
How does this happen?
Do RTs have to take extreme measures to fix this or what type of therapy needs
to be used? - ANSWER Cause:
Mixing of oxygenated and deoxygenated blood after passing through the lungs.
Treatment:
Responds well to traditional oxygen therapy.
During Mechanical Ventilation a rising Plateau Pressure would indicate _____
compliance.
During PCV a rising Volume indicates _____ compliance.
Measurement of compliance
- Dynamic compliance: Measured during _______
- Static compliance: Measured when ________ - ANSWER During volume-
controlled ventilation, rising plateau pressure indicates decreasing compliance
(and vice versa).
- During Pressure-Controlled Ventilation (PCV), increasing volume indicates
Increasing Compliance (and vice versa).
• Measurement of compliance:
1 Exam Study Guide
How is Compliance (CL) measured? - ANSWER CL = Change in Volume / Change
in Pressure
Compliance is a measure of the dispensability of the lungs:
- CL = The compliance of the lungs/thorax.
V = The change in volume (L).
P = The change in pressure (cm).
Static Compliance (Cst) - ANSWER The change in Volume in the respiratory
system for a given unit of applied pressure at the end of inspiration but before
exhalation.
Plateau Pressure (Pplat) - ANSWER A stable pressure measured at the end of an
inspiratory hold.
Airflow Resistance (Raw) - ANSWER The opposition to flow caused by frictional
forces and expressed as the ratio of driving pressure to the rate of gas flow.
Oxygenation Failure - ANSWER Severe Hypoxemia due to any condition.
Dead Space Ventilation - ANSWER The volume of a breath that does not
participate in gas exchange. It is ventilation without perfusion.
Pressure-Volume Slope - ANSWER The rate of change observed in a pressure-
volume plot of a breath.
Dynamic Compliance - ANSWER The change in volume for a given unit of applied
pressure when gas is moving in the respiratory system.
Ventilation-Perfusion Mismatch - ANSWER This occurs when the ideal
proportion of ventilation in a lung area is either greater or lesser than the
amount of blood flow.
Peak Inspiratory Pressure (PIP) - ANSWER The largest pressure attained during
inspiration.
Ventilatory Failure - ANSWER Occurs when the patient's minute alveolar
ventilation cannot keep up with the metabolic rate or CO2 production. O2 failure
, usually follows when the cardiopulmonary system cannot provide adequate O2
needed for metabolism.
Hypoxemia - ANSWER A lower than normal level of O2 in the blood.
Intrapulmonary Shunting - ANSWER A condition in which blood flowing through
a lung area is exposed to under-ventilated or unventilated alveoli, resulting in
significant hypoxemia.
Hypoxia - ANSWER A lack of sufficient O2 in the tissues or organs.
What causes Hypoventilation (Vent Failure) and the clinical presentation? -
ANSWER Causes:
Spinal Cord Injury
Neuromuscular Disorder
Overdose of Analgesics or Sedatives
Severe Airway Obstruction
Central Sleep Apnea
Clinical Presentation:
Reduced Minute Ventilation
Hypercapnea
One of the conditions leading to vent failure is Venous Admixture.
How does this happen?
Do RTs have to take extreme measures to fix this or what type of therapy needs
to be used? - ANSWER Cause:
Mixing of oxygenated and deoxygenated blood after passing through the lungs.
Treatment:
Responds well to traditional oxygen therapy.
During Mechanical Ventilation a rising Plateau Pressure would indicate _____
compliance.
During PCV a rising Volume indicates _____ compliance.
Measurement of compliance
- Dynamic compliance: Measured during _______
- Static compliance: Measured when ________ - ANSWER During volume-
controlled ventilation, rising plateau pressure indicates decreasing compliance
(and vice versa).
- During Pressure-Controlled Ventilation (PCV), increasing volume indicates
Increasing Compliance (and vice versa).
• Measurement of compliance:
