Anatomy September Flashcards
meninges
Dura mater
arachnoid
pia mater
Cerebrum
- Conscious though processes, intellectual functions
- memory storage and processing
- conscious and subconscious regulation of skeletal muscle contractions
Cerebellum
- Coordinates complex somatic motor patterns
- adjusts output of other somatic motor centers in brain and spinal cord
medulla oblongata
Controls blood flow through peripheral tissues
Cardiac and vasomotor centers
circle of willis
supplies blood to the brain
contains:
1. anterior communicating artery
2. middle cerebral artery
3. posterior cerebral artery
4. posterierior communicating artery
Choroid Plexus
Produces CSF
- removes waste products from CSF
Blood Brain Barrier (BBB)
some drugs can pass through BBB
What does the common carotid artery hold?
Common carotid artery holds the carotid body and carotid sinus and this rises from the glossopharyngeal nerve (IX)
Phrenic nerve
If you put ice in the chest and it is touching the phrenic nerve,
You can get Phrenic nerve paralysis which makes you unable to breathe
Cerebral Perfusion Pressure
CPP = MAP - ICP
MAP = Mean arterial Pressure
ICP = Intracranial Pressure
Slide 90
Thoracic Outlet Syndrome
three related syndromes – compression of nerves, arteries, and veins in lower neck
causes pain in the arm, shoulder, and neck
SLIDE 93
how much cardiac output and oxygen does the brain require
15% - cardiac output
O2 = 20%
slide 100
Appendicular skeleton
- upper limbs
- lower limbs
- pelvic girdle
slide 107
Sternotomy/ media sternotomy
when they cut the sternum to perform open heart surgery
bone can bleed
they close the sternotomy with wires and the sternum grows back
Cardiac muscle
Cardiac muscle cells
- Are small
- are typically branched with a single nucleus
- have short, wide T tubules
–> NO triads
- Have SR with no terminal cisternae
- are almost totally dependent on AEROBIC METABOLISM
–> contain lots of myoglobin, many mitochondria
- contact each other via INTERCALATED DISCS
SLIDE 184
Intercalated discs
Intercalated discs
- Specialized connections
- Join sarcolemmas of adjacent cardiac muscle cells by gap junctions and desmosomes
- Functions include
- Stabilizing positions of adjacent cells
- Maintaining three-dimensional structure of tissue
- Allowing ions to move from one cell to another
–> So cardiac muscle cells beat in rhythm
SLIDE 185
Characteristics of cardiac muscle
Automaticity
- Contraction without neural stimulation
- Controlled by pacemaker cells
- Nervous system can alter pace and tension of contractions
- Contractions last 10 times longer than those in skeletal muscle, and refractory periods are longer
- Wave summation and tetanic contractions are prevented due to special properties of sarcolemma
SLIDE 189
fluid dynamics
P = Q x R
the pressure gradient between two points is equal to the product of flow and resistance
Slide 192
hemodilution
cause viscosity to drop ,decrease resistance to flow, the resistance is the pts vascular system
Have to flow higher when you hemodilute
SLIDE 192
advantages to hemodilution & CPB priming solutions
SLIDE 193
Predicted HcT during CPB
Predicting HCT during CPB = Patients RBC volume before CPB/ (Patients estimated blood volume + CPB prime volume + pre-CPB intravenous fluid volume)
(Resistance) arterioles: friction
SLIDE 196
Perkinje fibers and SA Node
Slide 250
norepinephrine
- released by adrenergic synapses
- excitatory and depolarizing effect
- widely distributed in the brain and Porians of ANS
slide 253
Phrenic nerve
controls diaphragm
damage is common in cardiac surgery involving use of ice slush - paralyzing this vein and making it hard to breathe
vagus nerve
known as the tenth cranial nerve
carries sensory fibers that create a pathway that interfaces with the sympathetic control of the heart, lungs, and digestive tract.
it comprises two nerves - left and right vagus nerves
it is the longest nerve of the autonomic system and has both sensory and motor fibers
alveoli
they will ask questions about their physiology and gas exchanges…NOTHING about anatomy
max surface area, makes it possible for every RBC to become oxygenated
surfactant
oily secretion
coats the alveolar surface and reduces surface tension
external respiration vs internal respiration
Abnormal external respiration is dangerous - HYPOXIA - low tissue oxygen levels
IR: uptake of O2 and release of CO2 by cells
result of cellular respiration
- Anoxia - complete lack of oxygen in tissues
Daltons law
Each gas contributes to total pressure in proportion to its relative abundance
Partial pressure
Pressure contributed by a single gas in a mixture
In atmospheric air (760 mm Hg)
Nitrogen (N2) is 78.6 percent (597 mm Hg)
Oxygen (O2) is 20.9 percent (159 mm Hg)
Water vapor (H2O) is 0.5 percent (3.7 mm Hg)
Carbon dioxide (CO2) is 0.04 percent (0.3 mm Hg)
Partial pressures in plasma of pulmonary vein
PCO2 = 40 mm Hg
PO2 = 100 mm Hg
PN2 = 573 mm Hg
Gas exchange
Solubility of gases in body fluids
CO2 is highly soluble
O2 is somewhat less soluble
N2 has very limited solubility
henrys law
Diffusion between liquids and gases
At a given temperature, amount of a gas in solution is proportional to partial pressure of that gas
When gas under pressure contacts a liquid, pressure forces gas molecules into solution
At equilibrium -
Gas molecules diffuse out of liquid as quickly as they enter it
Number of gas molecules in solution is constant
oxyhemoglobin dissocation curve
The relationship between pO2 and SaO2 can be represented by the oxygen dissociation curve, whichrepresents oxygen saturation (y-axis) as a function of the partial pressure of oxygen (x-axis). The sigmoid or S-shape of the curve is due to the positive cooperativity of hemoglobin.
Slide 177
Bohr effect
the effect of pH on hemoglobin saturation curve
Caused by CO2
CO2 diffuses into RBCs
Carbonic anhydrase catalyzes reaction with H2O
Producing carbonic acid (H2CO3), which dissociates into hydrogen ion (H+) and bicarbonate ion (HCO3–)
Hydrogen ions diffuse out of RBC, lowering pH
