What, roughly, is the dividing line between the upper and lower respiratory tract? The larynx. What s the difference between the conducting zone and

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1 What, roughly, is the dividing line between the upper and lower respiratory tract? The larynx. What s the difference between the conducting zone and the respiratory zone? Conducting zone is passageways no exchange happening. Respiratory zone is where exchange happens. Name five organs of the conducting zone. Nasal passages, pharynx, mouth, trachea, larynx and bronchial tree. What makes up the respiratory membrane? 2 one-cell thick walls (alveolar and capillary), a tiny bit of connecting tissue and fluid. What are the three relevant pressures we ve discussed in class? Atmospheric, Intrapulmonary (alveolar) and intrapleural. What is the USUAL intrapulmonary pressure? +/- 1 mm Hg than atmospheric What s the typical intrapleural pressure? -2 to -8 relative to atmospheric pressure; AVERAGE OF -4; mm Hg Why is intrapleural pressure always negative? b/c of lung recoil, which is due to the elasticity of lung tissue and surface tension inside alveoli. Define pulmonary ventilation. The movement of air in and out of the lungs. When is air flow possible? When there s a pressure gradient between atmospheric and intrapulmonary pressures. What, basically, does Boyle s Law say? The pressure of gas or a gas mixture varies inversely w/its volume. Container gets smaller, pressure goes up. Finish this sentence: I have to spend energy to, but not to. Inhale, exhale. Why is exhalation passive? Elasticity of lung tissue and surface tension inside alveoli. Define lung compliance. How easily lungs inflate. What increases lung compliance? Surfactant (by 10x) What decreases lung compliance? (4 things.) Lack of surfactant, fibrosis of lung tissue, restricted airways and reduced flexibility of rib cage. Define atelectasis. A collapsed lung, or collapsed portion of lung. What s a pneumothorax and how is it treated? It s air in the pleural cavity. Treated with a chest tube. What s a tension pneumothorax? So much extra air in the pleural cavity that it pushes the heart and other lung to one side. Treated with needle decompression. What is hemothorax, and what is a hemopneumothorax? Hemothorax: A blood-filled space in pleural cavity. Hemopneumothorax: air and blood in pleural cavity. Who is prone to RDS, IRDS, and HMD? Very young or premature infants, or C-section babies. What are the three common components of these disorders? Lack of surfactant, small, noncompliant alveoli, and weak chest wall muscles. What s the treatment for these conditions? Positive pressure ventilation and surfactant. What is the critical period for these babies? Days 1-3. Tell me what Dalton s Law says. In a mixture of gases, each gas exerts a portion of the total pressure, proportional to its concentration in the mixture. What s our atmospheric pressure here? 760 mm Hg. What s the concentration of oxygen, and what s its partial pressure? [] = 21%, PP = 160 mmhg What s the concentration of atmospheric CO2, and what s its partial pressure? [] = 0.04%, PP = 0.3 mm Hg What does Henry s Law say? When you expose a liquid to a mixture of gases, each gas will dissolve into that liquid in proportion to its partial pressure. What must be true for this law to apply? The gas must be soluble in the liquid. Which partial pressure values does blood pick up? The partial pressure values of alveolar air. What s the rule of thumb about blood quality vs. air quality? The quality of blood will never be any better than the quality of alveolar air.

2 What is the average partial pressure of oxygen in the alveoli? 104 mm Hg. What is the partial pressure of carbon dioxide in the alveoli? 40 mm Hg. Why is the alveolar PCO2 so much more than the atmospheric PCO2? Because we don t empty the contents of our lungs when we exhale. Define tidal volume. What you breathe in. What are the amounts of tidal volume and residual volume? Tidal volume of 500 ml comes in and mixes with the residual volume of 2400 ml that s already in the lungs. What is respiration? The movement of gases. What is internal respiration? The exchange of gases at tissues. What is external respiration? Exchange of gases at lungs. What drives both internal and external respiration? Partial pressure gradients. Each gas follows its own PP at both lungs and tissues. How much alveolar surface do you have? 1,300 square feet. Enough to cover half a tennis court. What can happen to the respiratory membrane in cases of disease? It can be thickened. Name some diseases that can thicken the respiratory membrane? Pneumonia, emphasyma, lung cancer, tuberculosis and cystic fibrosis. What s the number one way to transport carbon dioxide, and also acts as a base to buffer and adjust ph? HCO3- (bicarbonate ion) What results from joining CO2 and H20, or from joining H+ and HCO3-? Carbonic acid, H2CO3. What enzyme in RBCs speed up the formation of carbonic acid by the union of carbon dioxide and water? Carbonic anhydrase. Carbaminohemoglobin is what? Hb carrying many molecules of carbon dioxide. What is carboxyhemoglobin? Hb carrying carbon monoxide instead of oxygen What is carbon monoxide? A colorless, odorless gas formed by the incomplete burning of organic fuels, such as gasoline, wood, coal, etc. What is deoxyhemoglobin? Hb that has released its oxygen to tissues and is temporarily carrying hydrogen ion. What s the name for hemoglobin saturated with oxygen? Oxyhemoglobin. What summary statement can be made about ventilation-perfusion coupling? If I m getting good ventilation in an alveoli, I ll send more blood to that alveoli. If I m not getting good ventilation in an alveoli, I ll send only the minimum amount of blood to it. Finish this sentence: We can control around our alveoli like we do in. Capillary beds, tissue. What are the partial pressures of oxygen and carbon dioxide in inspired air? PO2 is 160 mmhg and PO2 is 0.3 mmhg. What are the partial pressures of oxygen and carbon dioxide in the alveoli? PO2 is 104 mm Hg and CO2 is 40 mm Hg. What are the partial pressures of oxygen and carbon dioxide in blood entering the tissue capillaries? PO2 is 100 mmhg and PCO2 is 40 mm Hg. What are the partial pressures of oxygen and carbon dioxide IN THE TISSUES? PO2 is less than 40 mmhg and PCO2 is greater than 45 mmhg. What are the partial pressures of oxygen and carbon dioxide in blood leaving the tissue capillaries? PO2 is 40 mmhg, PCO2 is 45 mmhg. What are the partial pressures of oxygen and carbon dioxide in blood entering alveolar capillaries? PO2 is 40 mmhg, PCO2 is 45 mmhg. What are the partial pressures of oxygen and carbon dioxide in expired air? PO2 is 120mmHg and PCO2 is 27 mmhg

3 THREE-PART QUESTION: About how much oxygen attaches to something in the RBCs? What does the oxygen attach to? What do the oxygen and this thing form when they combine? 98%; deoxyhemoglobin; oxyhemoglobin. What happens with the other 2 percent of oxygen? It travels in the plasma. Finish this sentence: percent of CO2 joins with water to make, which splits into and. 70ish; carbonic acid; bicarb; hydrogen ion. What s the second most common form in which CO2 travels in blood? How is it formed? What percentage of CO2 travels this way? As carbaminohemoglobin on the RBC. It s made by combining CO2 and hemoglobin. About 23 percent of CO2 travels this way in the blood. What happens to the remaining 7% of Co2? It travels in the plasma as CO2. What is carbonic anhydrase? And where does it work? It s an enzyme that makes the CO2 reactions run faster. Works in the RBCs ONLY. What is cyanosis? The condition of having bluish colored skin. What is cyanosis a sign of (2 parts)? Too much deoxyhemoglobin being present; a sign of a problem with the lungs, the conducting passageways or the blood. What percentage of hemoglobin is oxygen-saturated in cyanotic patients? What s the normal level of oxygen saturation? Only about 75 percent. Normal is 98 percent. Where would you see signs of cyanosis first? Nail beds, fingertips and mucus membranes. What is the most common kind of poisoning? Carbon monoxide poisoning. What s happening in the blood when CO poisoning occurs? Carbon monoxide is competing with oxygen for binding sites on the Hb molecule. What is the affinity of HB for CO? 240x stronger than its affinity for oxygen. What happens as a result? Tissues become hypoxic, but NOT ischemic, as the blood becomes more saturated with CO. What color is a CO poisoning patient s skin? Why is this the case? Red, because carboxyhemoglobin reflects red better than oxyhemoglobin does. What symptoms appear in carbon monoxide poisoning? Reduced level of consciousness, syncope and death. How can CO poisoning be treated? With 100% O2 and a hyperbaric chamber, in order to give O2 an advantage. Where are the respiratory control centers located? In the brain stem. One in the pons, 2 in the medulla. What do you know about the ventral respiratory group? (A 5-point question! You can work together as a team!) It s located in the medulla; it appears to be the pacemaker for breathing; it sends impulses for respiration for about 3 seconds, then pauses for about 2, then sends for 3 more, creating a rhythmic pattern; signals go to the diaphragm and external intercostals; the VRG receives info from other sources and sends impulses in response to that info. What is upnea? Restful, quiet breathing. What do alcohol and narcotics do to respiratory control centers? Inhibit them, so that breathing slows down. People who binge on alcohol, or OD, die of respiratory failure. What s apnea? Lack of breathing. What s the difference between compensatory and noncompensatory?

4 Compensatory is your body fixing a problem. Noncompensatory means the RR IS the problem. What is ASA overdose? Aspirin overdose, acetyl salicylic overdose. Causes compensatory hyperventilation. Aspirin OD drops ph, which makes body think CO2 is elevated, and hyperventilation starts. This DOES raise ph. What happens in noncompensatory hyperventilation? Pnt is blowing off too much CO2, and ph will increase in response. If it goes on too long, pnt will go into respiratory alkalosis. This will cause muscle cramps, muscle spasms and tetany. If you find someone who s hyperventilating, and you DON T know whether it s because of an emotional response, what should you do? Let them faint. Don t let them hurt themselves. They ll fix themselves. What s the term for high CO2 in the blood? Hypercapnea. Give some examples of noncompensatory hypoventilation. Narcotics, alcohol, brain stem injuries. What s the concern with noncompensatory hypoventilation? Respiratory acidosis. Unconsciousness increases the risk of infarctions in a variety of places. This can lead to death. Explain hypoxic drive. In patients with chronic respiratory illnesses, their CO2 levels stay high and ph levels stay low, so that chemoreceptors learn to ignore those two indicators. As a result, the chemoreceptors rely on O2 levels to regulate. What does COPD stand for? Chronic Obstructive Respiratory Disease. What two flavors does it come in? Chronic bronchitis or obstructive emphysema. Or both! What happens to the alveoli in obstructive emphysema? Alveolar walls deteriorate. They ll be fewer and larger. This is a problem because it reduces the surface area where gas exchange can occur. Also, fibrosis will replace original tissue, resulting in decreased elasticity and therefore decreased lung recoil. What s the nickname for emphysema ptnts? Pink puffers. What s the nickname for chronic bronchitis ptnts? Blue bloaters. What s the main difference between heat exhaustion and heat stroke?

5 In heat exhaustion, the body s heat loss mechanisms are working aggressively, but they re not adequate. In heat stroke, the heat loss mechanisms have stopped working. How is the skin of a heat exhaustion ptnt different from the skin of a heat stroke ptnt? In heat exhaustion, ptnt s skin will be cool, clammy and pale. In heat stroke, skin will be hot, dry and red.