Respiratory Anatomy
What is the hilum?
Area of the lung where veins/arteries as well as mainstem bronchi enter lung architecture.
Describe pressure changes in lungs during inhalation/exhalation in comparison to atmospheric pressure
Inhalation: Pressure in lungs negative to atmospheric pressure --> air rushes in
Exhalation: Pressure in lungs positive to atmospheric pressure --> air forced out
What are the differences between veins and arteries? in terms of Tunica Adventita, Media and Intima, pressure, amount of blood held.
Veins have similar adventita, but smaller media and intima. Veins low pressure, arteries high pressure. Veins hold ~70% of all blood at any given moment (need to be stretchier - thinner walls).
What is end diastolic volume? End systolic?
End diastolic volume = volume of blood in ventricles right before ejection
End systolic volume = volume of blood in ventricles after ejection (start of isovolumic relaxation phase)
in 1836, how did the original patent for the fire hydrant get lost?
a fire
what is the carina?
Where the trachea branches into the mainstems
What keeps the lungs expanded, even during exhalation?
negative pressure of intrapleural space.
What are the epicardium, myocardium and endocardium made of?
Epicardium - connective tissue, elastic fibers, fat.
Myocardium - Cardiac muscular layer
Endocardium - Smooth muscle, elastic fibers.
In what stages of the cardiac cycle are all valves closed?
Isovolumic contraction and relaxation
Common cause of increased preload? Afterload?
Increased afterload: hypertension, aortic valve insufficiency
What are Type I and Type II Pneumocytes, including their prevalence in the lung and epithelial type.
Type I: Simple squamous cells involved in gas exchange (95% of lung). Vulnerable to injury
Type II: Simple cuboidal cells that make surfactant (5% of lung). Can turn into type I if needed.
What could a sudden, significant jump in a patient's V/Q indicate?
sudden drop in perfusion = thrombus/embolus rapidly decreasing blood flow to alveolar capillaries
If a patient has pulmonary valve regurgitation, that means blood has trouble moving through which compartments?
Trouble moving from R ventricle to Pulmonary trunk/arteries.
Draw and describe ion movement in a cardiac depolarization curve
1) sudden opening of Na channels causing Na influx and increase in charge.
2) At -40mV, Ca2+ channels open, Ca2+ influx -> further increase in charge.
3) Reaches 0mV and Na channels close, and shortly after K+ channels open, causing K+ efflux, lowering charge. Ca2+ channels still open.
4) K+ efflux and Ca2+ influx cancel out, plateau.
5)Gradual closure of Ca2+ channels causes gradual decrease in charge.
In what state is it legal to hunt unicorns?
Michigan
Describe the sections of respiratory epithelium and presence/absence of goblet cells for both conductive and respiratory divisions.
Pharynx & Larynx - Non-keratinized stratified squamous, no goblets
Trachea & Bronchi - Ciliated pseudostratified columnar, lots of goblets
Bronchioles - Simple Cuboidal, few to no goblets
Alveoli - Simple Squamous, no goblets
Explain right shift and left shift in terms of P50 deviation & O2 affinity. How do they relate to pH, 2,3 BPG and temp?
Right shift: P50 is greater than normal (higher pO2 needed to achieve 50% saturation of Hgb) This means that affinity for O2 is decreased, resulting in more O2 dropped off in tissues. Caused by low pH, high 2,3 BPG and high temp
Left shift: P50 is lower than normal (lower pO2 needed to achieve 50% Hgb saturation). Means affinity to O2 is increased, resulting in less O2 dropped off in tissues. Caused by high pH, low 2,3 BPG, low temp
What is the reasoning for high levels of branching in cardiac muscle cells? What do the intercalated discs do?
High amount of branching allows for synchronized contraction in many planes (Squeeze). Intercalated discs help move electrical stimuli and Ca2+ from cell to cell quickly (high density of gap junctions)
What stage of the cardiac cycle is S1 and S2 in?
S1: start of Isovolumic contraction
S2: Start of Isovolumic relaxation
Describe the regions of lung in terms of V/Q ratios
Superior lungs: V>Q
Middle lungs: V=Q
Inferior lungs = V<Q
Interstitial lung disease is caused by abnormal accumulation of what cell?
Fibroblasts (between alveolar cells, increased number causes increased ECM secretion --> decreased respiratory function)
What would have a more protein-rich pleural effusion, Transudative or exudative?
Exudative!
Transudative effusion is due to increased HP of capillaries (forcing fluid out into pleura i.e. heart failure causing backup of blood in lungs) or decreased oncotic pressure of capillaries (also forcing fluid out into pleura i.e. liver disease, liver cant make proteins in blood at normal levels) - protein poor fluid
Exudative is due to inflammation or injury causing increased vascular permeability (e.g. pneumonia, cancer, TB) - proteins leak out --> protein rich fluid
Describe where each node and bundle are in the electrical system of the heart. Which ones have sympathetic input?
SA node: R atrium, sympathetic input
AV node: lower Interatrial septum. Most input from SA node but some sympathetic
AV bundle: arises from AV node, turns into bundle branches which travel down ventricular septum
Purkinje fibers: branch from bundle branches at apex of heart and connect with contractile cells.
What is starling's law? How does it related to things like premature ventricular contractions? What's the end goal?
Starling's law - heart has ability to change contractility in accordance with changes in preload.
eg. PVCs - heart beats too fast, causing decreased preload before ejection -> decreased ESV. Heart corrects itself by allowing extra refill time before next beat to return to normal ESV.
What sea creatures have been used in war?
Dolphins, beluga whales, sea lions were trained by US navy in the vietnam and persian gulf wars to bring equipment to divers, spotting and marking mines, and for underwater surveillance (putting a camera in their mouth). Russians did this in the cold war too.
Avatars also ride sea creatures in Avatar 2