The Respiratory System Part 2 Flashcards
what are the THREE STEPS OF PULMONARY VENTILATION?
- PULOMNARY VENTILATION: BREATHING
- EXTERNAL (PULMONARY) VENTILATION
- INTERNAL (TISSUE) VENTILATION
define PULMONARY VENTILATION: BREATHING
- process of INHALATION (INFLOW) + EXHALATION (OUTFLOW)
- have AIR EXCHANGE between the AIR and the ALVEOLI
define EXTERNAL (PULMONARY) VENTILATION
- the EXCHANGE OF GASES between the ALVEOLI and BLOOD within the PULMONARY CAPILLARIES
- BLOOD CAPILLARIES; begin to GAIN OXYGEN and LOSE CO2
define INTERNAL (TISSUE) VENTILATION
- the EXCHANGE OF GASES between the BLOOD within the SYSTEMIC CAPILLARIES and TISSUE CELLS
- BLOOD: the LOSS OF OXYGEN and GAIN OF CO2
- see METABOLIC REACTIONS OCCUR (ATP USED)
describe the relationship of MECHANICAL PROCESSES that DEPEND on VOLUME CHANGES within the THORACIC CAVITY
** VOLUME CHANGES = PRESSURE CHANGES
** PRESSURE CHANGES = GASES FLOW in order to EQUALIZE the SAID PRESSURE
describe INHALATION
- DIAPHRAGM is CONTRACTING
- CHEST EXPANSION
- ALVEOLAR PRESSURE DECREASES (less than atm pressure)
describe EXHALATION
- DIAPHRAGM is RELACING
- CHEST CONTRACTION
- ALVEOLAR PRESSURE INCREASES (greater than atm pressure)
definition of ATMOSPHERIC PRESSURE (PATM)
- the PRESSURE exerted by the AIR SURROUNDING THE BODY
- typically 760 mm Hg at sea level = 1 atm
what are the RESPIRATORY PRESSURES?
**important to note; all are RELATIVE and CORRELATED to our ATMOSPHERIC PRESSURES
- NEGATIVE RESPIRATORY PRESSURE = LESS THAN PATM
- POSITIVE RESPIRATORY PRESSURE = GREATER THAN PATM
- ZERO RESPIRATORY PRESSURE = PATM
definition of INTRAPULMONARY PRESSURE (PPUL)
- the PRESSURE within the ALVEOLI ITSELF–the PRESSURE within the LUNGS ITSELF
- begins to FLUCTUATE WITH BREATHING
- always begins to eventually EQUALIZE with the Patm
INSPIRATION;
- beceomes LESS THAN PATM
EXPIRATION;
- becomes GREATER THAN PATM
describe INTRAPLEURAL PRESSURE (PIP)
- pressure that is WITHIN THE PLEURAL CAVITY
- also begins to FLUCTUATE with BREATHING–dependent on the VENTILATION PHASE
- **is ALWAYS A NEGATIVE PRESSURE (Pip < Patm & Ppul)
what happens if we have a POSITIVE PRESSURE OF PIP?
- can lead to PNEUMOTHORAX (damage and rupturing etc..)
what happens if we have TWO INWARD FORCES of PRESSURE?
leads and promotes LUNG COLLAPSE–have POSITIVE FORCES coming from INSIDE AND OUTSIDE
- have ELASTIC RECOIL OF LUNGS–decrease of LUNG SIZE
- have SURFACE TENSION OF ALVEOLAR FLUID–reduces the ALVEOLAR SIZE
what happens if we have ONE OUTWARD FORCE?
this tends to ENLARGE THE LUNGS due to the ELASTICITY OF THE CHEST WALL–pulls the THORAX OUTWARD
definition of TRANSPULMONARY PRESSURE
the DIFFERENCE BETWEEN THE INTRAPULMONARY PRESSURE and the INTRAPLEURAL PRESSURE
- specific PRESSURE that KEEPS AIR SPACE OF LUNGS OPEN and prevention of COLLAPSE
- determines SIZE OF LUNGS
**IF ANYTHING EQUALIZES BOTH PRESSURES = LUNG COLLAPSE
definition of ATELECTASIS
- aka as LUNG COLLAPSE
- see PLUGGED BRONCHIOLES + the COLLAPSE OF ALVEOLI
CONDITIONS:
Pip = Ppul
Pip = Patm
(Pip is always a NEGATIVE PRESSURE–keeps lungs INFLATED)
defintion of BOYLE’S LAW
- specfic pressure changes that DRIVE INHALATION and EXHALATION
- the VOLUME OF GAS VARIES INVERSELY WITH PRESSURE