《病理生理学》课程教学课件（PPT讲稿）Chapter 4 Hypoxia

Classification,etiologyandpathogenesis1.Hypotonichypoxia—PaO2lCauses : 1) PiO212)pulmonary dysfunction3)shuntResults:PaO21SaO21→CaO21cyanosishypotonic hypoxemia,(PaO2-PMO,)-→（CaO2-CvO2)↓PaO, <60mmHg → VO21?

Classification, etiology and pathogenesis 1. Hypotonic hypoxia — PaO2↓ Causes : 1) PiO2↓ 2) pulmonary dysfunction 3) shunt Results : PaO2↓→ SaO2↓→ CaO2↓ hypotonic hypoxemia, cyanosis （PaO2－PMO2）↓ →（CaO2－CvO2）↓ PaO2 ＜ 60mmHg → VO2↓？

2.Hemic hypoxia-CO2max↓Causes: 1) anemia2)carboxyhemoglobinemia3)methemoglobinemiaenterogenous cyanosis4)Psol:transfusion ofdepotbloodResults:CO,max11 -CaO211→（CaO2-CvO,）P50 ↓→(CaO2-CvO,)

Results : CO2max↓↓  CaO2 ↓↓ （CaO2－CvO2）↓ P50 ↓  （CaO2－CvO2）↓ 2. Hemic hypoxia — CO2max ↓ Causes : 1) anemia 2) carboxyhemoglobinemia 3) methemoglobinemia enterogenous cyanosis 4) P50↓：transfusion of depot blood

3.Circulatory H-QCauses : general circulatory failurelocal circulatory disorderResult : Qll→ CvO2l→（CaO-CvO,)1

Result : Q↓↓→ CvO2↓ →（CaO2－CvO2）↑ Causes : general circulatory failure local circulatory disorder 3. Circulatory H — Q↓ ·