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 About the spleen during hemorrhage from Guyton & Hall, Textbook of Medical Physiology,12 th edition, 2011 p “….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.”

Gas exchange In what forms are O 2 and CO 2 found in the blood?

FlatSteep

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 O 2 ) and thus more O 2 is unloaded into the tissues. Shifting the Oxyhemoglobin dissociation curve Notice the main affect is on the steep portion of the curve which means that there is little influence on the loading of O 2 onto Hb in the lungs

Table 13.09

Figure Ventilation is relatively unaffected by PaO2 until it falls below 60. Explain why!

Chloride Shift carbaminohemoglobin CA = carbonic anhydrase Carbon dioxide transport Hb is a Buffer

Carbon Dioxide reacts with water! CO 2 + H 2 0 ↔ H 2 CO 3 ↔ H + + HCO 3 - Carbonic Acid Bicarbonate H + can’t cross Blood Brain Barrier but CO 2 does! Central Chemoreceptors respond to H+ produced by diffusion of CO 2 into brain interstitial fluid.

i.e. lactic acid

Any deviation from the set point for CO2 Causes immediate changes in ventilation! Why should this be so? Any deviation from the set point for CO2 Causes immediate changes in ventilation! Why should this be so?

Figure S 3 V A =( )X12 V A = 4.2 L/min

Figure Negative feedback loop for control of blood gases Cervical spinal cord injury S 4

Figure Name the components of the negative feedback loop S 5

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? Respiratory Physiology during Exercise S 6

Experience, learning, modification of motor program, feed forward! Negative feedback operates! But the changes in ventilation at the onset and offset of exercise cannot be explained by negative feedback. S 7

Figure Integrator S 8

S 9

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