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Interested in medical school and osteopathic programs?. Current students from VCOM will give a presentation and answer questions about their school and the admission process. In RMSC 121 starting at 6:30pm, Wednesday Nov 28 th. Progress on the HD.
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Interested in medical school and osteopathic programs? • Current students from VCOM will give a presentation and answer questions about their school and the admission process. • In RMSC 121 starting at 6:30pm, Wednesday Nov 28th.
Progress on the HD About the spleen during hemorrhage from Guyton & Hall, Textbook of Medical Physiology,12th edition, 2011 p. 175. “….the spleen is a special reservoir that contains large quantities of concentrated red blood cells. These can then be expelled into the general circulation whenever the sympathetic nervous system becomes excited and causes the spleen and its vessels to contract. As much as 50 millileters of concentrated red blood cells can be released into the circulation, raising the hematocrit 1 to 2 percent.”
In what forms are O2 and CO2 found in the blood? Gas exchange
Steep Flat
Shifting the Oxyhemoglobin dissociation curve At 40 Torr, more DPG, higher temperature, and greater acidity (all indicative of increased metabolism) shift dissociation curve down (Hb has a lower affinity for O2) and thus more O2 is unloaded into the tissues. Notice the main affect is on the steep portion of the curve which means that there is little influence on the loading of O2 onto Hb in the lungs
Figure 13.34 Ventilation is relatively unaffected by PaO2 until it falls below 60. Explain why!
carbaminohemoglobin Chloride Shift CA = carbonic anhydrase Hb is a Buffer Carbon dioxide transport
40 46 40 46
Carbon Dioxide reacts with water! CO2 + H20 ↔ H2CO3 ↔ H+ + HCO3- Carbonic Acid Bicarbonate H+ can’t cross Blood Brain Barrier but CO2 does! Central Chemoreceptors respond to H+ produced bydiffusion of CO2 into brain interstitial fluid.
Any deviation from the set point for CO2 Causes immediate changes in ventilation! Why should this be so?
Figure 13.22 S 3 VA=(500-150)X12 VA= 4.2 L/min
S 4 Figure 13.32 Negative feedback loop for control of blood gases Cervicalspinal cordinjury
Figure 13.40 S 5 Name the components of the negative feedback loop
S 6 Respiratory Physiology during Exercise Blood gases and pH change very little except when exercise is intense. Therefore, changes in minute ventilation are not the result of negative feeback. How can this be?
S 7 Negative feedback operates! But the changes in ventilation at the onset and offset of exercise cannot be explained by negative feedback. Experience, learning, modification of motor program, feed forward!
Figure 13.43 S 8 Integrator
HAPE = High Altitude Pulmonary Edema Tissandier and the brothers Croce-Spinelli 1875 balloon ascent to 8600 meters. Sudden reduction in Cabin Pressure at 40,000 ft. Felix Baumgartner’s Skydive from Space