Midterm Flashcards
Occurs in a ventilatory region where gas exchange perfusion is not available
Deadspace ventilation
The other type of ventilatory region is in alveoli, where gas exchange perfusion is available. Ventilation here is referred to as?
Effective alveolar ventilation (VAeff)
The volume of the conducting airways from the mouth/nose down to and including the level of the terminal bronchiole
Anatomic Deadspace (VDan)
The volume of malfunctioning alveoli that are lacking normal gas exchange perfusion
Alveolar Deadspace (VdA)
The total volume of deadspace inthe pulmonary system; consists of the sum of the anatomic and physiologic deadspace combined; may also be referred to as Functional deadspace.
Physiologic Deadspace (Vd)
alveolar units where the quantity of ventilation exceeds the quantity of perfusion available; results in a partial deadspace ventilation effect
Ventilation in excess of perfusion
This test is based on having the subject inhale and breathe 100% oxygen (O2). ). It can be performed as a single-breath 02 inspiration test (single breath N2 elimination) or during the initial breaths of a test requiring prolonged oxygen rebreathing (N2 washout for FRC)
The Fowler Test
The equipment needed to perform the Bohr test includes:
spirometer for measuring exhaled volumes, a
Douglas bag for collecting an exhaled gas sample, a
CO2 analyzer, and an
End-tidal PCO2.
Required to ensure complete exhaled gas collection.
Nose clips
For Vd/Vt, normal values range between:
-20 and .40 (.25 and .35 in some references)
For Vd/Vt, normal values range between:
-20 and .40 (.25 and .35 in some references)
Sometimes referred to as the single-breath oxygen test (SBQ), involves having the subject inhale a breath of 100% oxygen
Single-breath nitrogen elimination test (SBN2)
This Phase is the initial 0.0% N2 concentration measured during the emptying of the Vdan.
Phase 1
This phase is the rapid increase in % N2 that indicates the transition from Vdan to alveolar gas. This is determined as described earlier in the chapter for Vdan determination.
Phase 2
This phase is the relative % N2 plateau that results from the emptying of mixed gas from the alveoli during expiration.
Phase 3
This phase occurs toward the end of the expiration in most subjects. It is a relatively rapid increase in % N2 from the Phase TI1 plateau that continues with exhalation to the RV level.
Phase 4
Involve having the subject breathe the radioactive gas xenon 133 (Xe^133)
Ventilation scans
it is made of the lungs during the breathing of the gas
Scintiscan
Are made to record the process and pattern of the distribution of the Xe^133 in the lungs.
Scintiphotographs
Involve the intravenous injection of a radioactively tagged substance
Perfusion scans
A commonly used carrier and is processed into microspheres, or particles that are large enough to be caught and held in the pulmonary capillary circulation.
Human Albumin
