Anatomy and Physiology Flashcards
Lateral borders of the trachea run ___ into the ___
perpendicular into the suprasternal notch
The sternal angle AKA angle of Louis the point where what attaches
The point of anterior attachment of the 2nd rib and the tracheal bifurcation
True ribs
1 to 6 - AKA costosternal ribs - they have a single anterior costchondral attachment to the sternum
False ribs
7-10 - AKA costochondral ribs - they share costochondral attachments before attaching anteriorly to the sternum
Ribs 11 and 12
Floating ribs - or costovertebral ribs
They have no anterior attachment
Posterior border of the sternum
vertebral column from T1 to T12
Upper airway consists of what
Nose or mouth
Pharynx (used for both resp. and dig)
Larynx (connects pharynx to trachea)
Lower airways
Conducting airways = trachea to terminal bronchioles (transport air ONLY)
Respiratory unit = resp bronchioles, alveolar ducts, alveolar sacs, alveoli - diffusion of gas occurs through all of these!
Right lung divides into
3 lobes by oblique and horizontal fissure lines
Each lobe divides into segments
10 segments total
Left lung divides into
two lobes by single oblique fissure line
Each lobe is divided into segments
8 segments total
Parietal pleura covers
Inner surface of thoracic cage, diaphragm, and mediastinal border of the lung
Visceral pleura covers
Wraps outer surface of the lung including the fissure lines
Intrapleural space is what
the potential space between the two pleura that maintains the approximation of the rib cage and the lugs allowing forces to be transmitted from one structures to another
Primary muscle of inspiration
diaphragm
When the diaphragm is at rest the hemidiaphragm is where
arched high into the thorax
When the diaphragm contracts what happens
the central tendon is pulled downward - flattening the dome
The result is protrusion of the abdominal wall during inhalation
Additional primary muscles of inhalation besides diaphragm include
portions of the intercostals
Accessory muscles of inspiration are used when
when a more rapid or deeper inhalation is required or with disease states
Accessory muscles of inspiration include what
Upper two ribs raised by SCM
Rest of ribs raised by levator costarum and serratus
With fixed shoulder girdle, trap, pectorals, and serratus can be mm of inspiration
Expiratory muscles of ventilation - Resting exhalation results from what
a passive relaxation of the inspiratory muscles and the elastic recoil tendency of the lung
Expiratory muscles are used when
a quicker and/or fuller expiration is desired, as in exercise or disease states
Expiratory muscles include
quadratus lumborum, portions of intercostals, muscles of abdomen and triangularis sterni
Pts who lack abdominal musculature (like SCI) tend to have what resting position of diaphragm
a lower resting position
decreasing inspiratory reserve
The more upright the body position, the ___ the diaphragm and ___ the inspiratory capacity
The lower the diaphragm
Lower inspiratory capacity
The more supine the body position the more ____the diaphragm
the more adventitious the position of the diaphragm
Mechanics of breathing -
Elastic recoil of lung parenchyma pulls lungs and pleura and thorax into position of exhalation (inward pull)
Bony thorax pulls thorax and pleura and lungs into position of inspiration (outward pull)
Resting end expiratory pressure (REEP) is what
the point of equilibrium where the forces in mechanics of breathing are balanced
Occurs at end tidal expiration
Tidal volume
volume of gas inhaled (or exhaled) during a normal resting breath
Inspiratory reserve volume
volume of gas that can be inhaled beyond a normal resting tidal inhalation
Expiratory reserve volume
volume of gas that can be exhaled beyond a normal resting tidal exhalation
Residual volume
volume of gas that remains in the lungs after ERV has been exhaled
Inspiratory capacity
(IRV + TV)
The amount of air that can be inhaled from REEP
Vital capacity
(IRV + TV + ERV)
the amount of air that is under volitional control
measured as forced expiratory vital capacity (FVC)
Functional residual capacity
(ERV + RV)
the amount of air that resides in the lungs after normal resting tidal exhalation
Total lung capacity
(IRV + TV + ERV + RV)
the total amount fo air that is contained within the thorax during a maximum inspiratory effect
Flow rates - FEV1 (forced expiratory volume in 1 second)
The mount of air exhaled during the first second of FVC
In healthy, at least 70% of FVC is exhaled in first second
Forced expiratory flow rate (FEF)
the slope of a line drawn between the points 25% and 75% exhaled volume on a forced vital capacity exhalation curve
FEF vs. FEV1
FEF is more specific to smaller airways and shows more dramatic change with disease than FEV1
Arterial oxygenation is what
The ability of arterial blood to carry oxygen
Arterial oxygenation - Partial pressure of oxygen in the arterial blood (PaO2) depends on
the integrity of the pulmonary system, the circulatory system and the Pa)2
Arterial oxygenation - PaO2 at room air is
95-100 mm Hg
Arterial oxygenation - Mild hypoxemia is what (number)
Less than 90 mm Hg PaO2
Arterial oxygenation - Hyperoxemia is what (number)
Over 100 for PaO2
Arterial oxygenation - Fraction of oxygen in the inspired air (FiO2) is what
percentage of oxygen in air based on a total of 1.00
Arterial oxygenation - FiO2 at room air is what
21% oxygen - usually written as 0.21
Arterial oxygenation - Supplemental oxygen is usually given when PaO2 falls below
55mm Hg
Alveolar ventilation is what
ability to remove carbon dioxide from pulmonary circulation and maintain pH
Alveolar ventilation - pH indicates what
the concentration of free floating hydrogen ions within the body
Alveolar ventilation - pH norm
7.35-7.45
Alveolar ventilation - PaCO2 is what
Partial pressure of carbon dioxide within the arterial blood
Alveolar ventilation - PaCO2 norm
35-45 mm Hg
Alveolar ventilation - Hypercapnea is what (number) and Hypocapnea is what (number)
Hyper is over 45
Hypo is less than 35
Alveolar ventilation - an increase in PaCO2 does what to pH
Decreases it
Alveolar ventilation - HCO3 is what
amount of bicarbonate ions within the arterial blood
Alveolar ventilation - HCO3 norm
22-28 mEq/L
Alveolar ventilation - HCO3 removal or retention changes pH how
direct relationship
more you have, the higher the pH
Optimal respiration occurs when
ventilation and perfusion are matched
Dead space is what
a space that is well ventilated but in which no respiration (gas exchange) occurs
Shunt
No respiration occurs because of a ventilation abnormality
Complete atelectasis of a respiratory unit allows the blood to travel through the pulmonary capillary without gas diffusion
Effect of body position on ventilation perfusion relationship - upright position
Perfusion is gravity dependent
In upright, more pulmonary blood is found at the base of the lung
Ventilation - at static the apical alveoli are fuller but with inspiration the base gets air
Ventilation perfusion ratio (V/Q) -
the ratio of pulmonary alveolar ventilation to pulmonary capillary perfusion
Effect of body position on ventilation perfusion relationship - upright position - V/Q ratio
apices are gravity independent with the lowest blood flow (Q) in upright position
There is more air than blood though so you have a high V/Q ratio `
Effect of body position on ventilation perfusion relationship - upright position - other positions
all positions will give you three zones - gravity independent, middle, gravity dependent
The gravity ind area of the lung acts as dead space
The gravity dep area of the lung acts as a shunt
