Author(s): Louis DAlecy, 2009

License: Unless otherwise noted, this material is made available under the terms of the Creative Commons AttributionNon-commercialShare Alike 3.0 License: http://creativecommons.org/licenses/by-nc-sa/3.0/We have reviewed this material in accordance with U.S. Copyright Law and have tried to maximize your ability to use, share, and adapt it. The citation key on the following slide provides information about how you may share and adapt this material.

Copyright holders of content included in this material should contact open.michigan@umich.edu with any questions, corrections, or clarification regarding the use of content.

For more information about how to cite these materials visit http://open.umich.edu/education/about/terms-of-use.

Any medical information in this material is intended to inform and educate and is not a tool for self-diagnosis or a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional. Please speak to your physician if you have questions about your medical condition.

Viewer discretion is advised: Some medical content is graphic and may not be suitable for all viewers.

Citation Key for more information see: http://open.umich.edu/wiki/CitationPolicy Use + Share + Adapt

Make Your Own Assessment

Creative Commons Attribution License Creative Commons Attribution Share Alike LicenseCreative Commons Attribution Noncommercial LicenseCreative Commons Attribution Noncommercial Share Alike LicenseGNU Free Documentation LicenseCreative Commons Zero WaiverPublic Domain Ineligible: Works that are ineligible for copyright protection in the U.S. (USC 17 102(b)) *laws in your jurisdiction may differPublic Domain Expired: Works that are no longer protected due to an expired copyright term.Public Domain Government: Works that are produced by the U.S. Government. (USC 17 105)Public Domain Self Dedicated: Works that a copyright holder has dedicated to the public domain.Fair Use: Use of works that is determined to be Fair consistent with the U.S. Copyright Act. (USC 17107) *laws in your jurisdiction may differOur determination DOES NOT mean that all uses of this 3rd-party content are Fair Uses and we DO NOT guarantee that your use of the content is Fair.To use this content you should do your own independent analysisto determine whether or not your use will be Fair. { Content the copyright holder, author, or law permits you to use, share and adapt. }{ Content Open.Michigan believes can be used, shared, and adapted because it is ineligible for copyright. }{ Content Open.Michigan has used under a Fair Use determination. }

*O2 and CO2 TransportM1 Cardiovascular/Respiratory SequenceLouis DAlecy, Ph.D. Fall 2008

*Tuesday 11/18/08, 9:00 O2 and CO2 Transport35 slides, 50 minutesDescribe the amount of oxygen dissolved and combined in blood.Define oxygen delivery to a tissue.Describe the characteristics of the oxygen-Hb saturation curve.Describe the shifts produced in the oxygen-Hb saturation curve.Describe the effects of anemia on oxygen content and PO2.State the three forms in which CO2 is carried in the blood.Describe the role of carbonic anhydrase in CO2 transport.Describe the chemical events associated with the uptake and release of CO2.Defines chloride shift.

*O2 content of blood = Dissolved + Hb bound O2 Liquid bloodAlveolar gasSource Undetermined

*How much gas is dissolved ?A gas dissolves in a liquid in direct proportion to

its partial pressure and solubility.

Henrys Law

*Henrys Law for O22CdO2content of dissolved O2 mL/dLaO2solubility coefficient for O2 in blood==The content of dissolved oxygen is equal to the product of the oxygen solubility coefficient and oxygen partial pressure.Linear straight lineRelationship likey = mx. dL = 100 mL

*Dissolved O2At PO2 of 100 mmHg X 0.0031 you get 0.3 mL O2/dL dissolved oxygen in blood.

With cardiac output of 5000 ml/min or 50 dL/min you would deliver (50 dL X 0.3 mL/dL) or 15 mL O2/min. BUTWe consume 20 X that or 250 mL O2/min so dissolved just will not do it!!

You need hemoglobin to bind and transport O2.dL = 100 mL

*HemoglobinZephyris (wikipedia),

*AirAirRBCHb-O2 bound + O2 dissolvedNot all Hb has O2PlasmaDissolved onlyDAlecy

*How much O2 is in blood?Concentration = ContentmL/dL = mL/100mL = Vol%(mL of O2 in 100 mL blood)i.e. arterial blood has 20 Vol% O2 Content %Hb Saturation% Hb Saturation = O2 bound to Hb X 100% O2 capacity of Hb

*O2 content (with flow) determines O2 delivery. So why do we talk about O2 saturation?O2 Content %Hb SaturationO2 saturation is relatively easier to measure and O2 content is much more difficult to measure. We need to understand the differences!!!!Thus O2 content is more important to O2 delivery than is O2 saturation.

*Hb Saturation CurveNormal Arterial Blood

~ 27 mmHgLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*Linear straight linerelationship. Most O2combined.% Hb SatOr SatO2 Content (mL / 100mL)Source Undetermined

*Different amounts of Hb but all 100% saturated !Hb=10 Hb=15 Hb=20 Normal blood Hb = 15 gm/dLO2 Content (mL / 100mL)HbO2 Saturation (%)Source Undetermined

*DO2 (cc/m2 /min)CI (L/m2 /min)Anemia orBlood lossBartlett, Critical Care Physiology

*i.e. ANEMIA1. Decreased number of RBC

2. Decreased Hb content per RBC Decreased Hb concentration so that % saturationcan be normal (97-100%) but O2 content is decreased. Normal blood Hb = 15 gm/dL

*Breathing100% O2. Denver ?O2 bars?O2 Content (mL / 100mL)Source Undetermined

*Hemoglobin Bound Oxygen Content mL O2 /dLCbO= SO2[ Hb ] Hbs2SO2= % Hb saturation[ Hb ]= hemoglobin content gm/dL bloodHbs= saturated Hb O2 content mL O2 /gm HbHbs= 1.36 mL O2 /gm Hb = O2 capacity= O2 bound to Hb X 100% O2 capacity of Hb

*Typical Arterial Blood Oxygen ContentOP2= 100 mm HgSO2= 97%[ Hb ] = 15 gm/dLCdO2aO2PO2= 0.0031 x 100 = 0.31 mL / dLDissolved O2Bound O2CbO= SO2[ Hb ] Hb2= 0.97 x 15 x 1.36 = 19.79 mL / dLTotal Oxygen ContentCdO2+CbO2= 0.31 + 19.79 = 20.1 mL / dL=s

*673breathing 100% O2100%Bound CbO2 19.97 mL / dL 20.1

Dissolved CdO2 0.31 2.1

Total CO2 20.1 22.2 HbO2 Saturation (%)Source Undetermined

*Breathing 100% O2Normal Hb 15 g/dlAnemia Hb 7.5 g/dl 6732210067312100Breathing Room AirNormal Hb 15 g/dlAnemia Hb 7.5 g/dl 10020971001097Thus breathing 100% O2 does not fix reduced oxygen transport capacity due to anemia. Content

*DO2 (cc/m2 /min)CI (L/m2 /min)Anemia orBlood loss2X or 3X CO could compensateBartlett, Critical Care Physiology

*pH on O2 Saturation of HbAcid unloads O2 from Hb (Bohr Effect)At any PO2 less O2 boundLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*CO2 on O2 Saturation of HbCO2 unloads O2 from Hb (Bohr Effect)At any PO2 less O2 boundLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*Temperature on O2 Saturation of HbTemperature unloads O2 from HbAt any PO2 less O2 boundLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*2,3-BPG on O2 Saturation of HbMore 2,3-BPG unloads O2 from HbLost in stored blood ~ cant unload O2 Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*Venous blood on O2 Saturation of HbVenous bloodVenous blood unloads O2 from HbP50 is PO2 at 50% O2 saturation.Arterial bloodLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*right shift (tissues) H+ (Bohr shift)CO2temperature2,3 BPGH+ CO2temperature2,3 BPGleft shift(lungs)SummaryAt any PO2 less O2 bound.At any PO2 more O2 bound.Source Undetermined

*right shift tissuemetabolismO2 is unloaded in tissuesDAlecy

*tissue ISFplasmaRBCCO2CO2CO2+ H2OH2CO3HCO3- + H+HbO2O2+ HHbC.A. = carbonic anhydraseCl-O2O2BohrshiftchlorideShifts inIn tissues O2 is unloaded from blood. In tissues CO2 is stored in blood (for transport). BufferAction.Source Undetermined

*alveolusplasmaRBCCO2CO2CO2+ H2OH2CO3HCO3- + H+HbO2O2+ HHbCl-O2O2Haldane shiftchlorideShift outHCO3-In lungs CO2 is unloaded from blood. In lungs O2 is stored in blood. C.A. = carbonic anhydraseSource Undetermined

*=ax = dissolved gas content mL/dL =0.06 mL / mm Hg /dLaCO2How is CO2 Transported?CO2 is about 20 x more soluble than O2But still only 5% (art.) to 10% (ven.) of transport is dissolved!!The content of dissolved gas (Cdx) is the product of the solubility coefficient (ax) and the partial pressure of the gas (Px).

*MostSomeH+ + Hb-NHCOO- = Hb + CO2 + H2O = H+ + HCO3-Carbonic AnhydraseLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*Reduced (de-ox)Hb binds more CO2 than HbO2Source Undetermined

*Source Undetermined

*Reduced (de-ox)Hb binds more CO2 than HbO2 ,venous blood can carry more CO2 then arterial blood. Venous blood

Arterial bloodVenousArterialLevitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.

*right shift (tissues) H+ (Bohr shift)CO2temperature2,3 BPGH+ CO2temperature2,3 BPGleft shift(lungs)SummaryAt any PO2 less O2 bound.At any PO2 more O2 bound.Source Undetermined

Slide 5: Source UndeterminedSlide 9: GFDL, Zephyris (wikipedia), http://en.wikipedia.org/wiki/GNU_Free_Documentation_LicenseSlide 10: DAlecySlide 13: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 14: Source UndeterminedSlide 15: Source UndeterminedSlide 16: Bartlett, Critical Care PhysiologySlide 18: Source UndeterminedSlide 21: Source UndeterminedSlide 23: Bartlett, Critical Care PhysiologySlide 24: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 25: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 26: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 27: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 28: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 29: Source UndeterminedSlide 30: DAlecySlide 31: Source UndeterminedSlide 32: Source UndeterminedSlide 34: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 35: Source UndeterminedSlide 36: Source UndeterminedSlide 37: Levitzky. Pulmonary Physiology. McGraw-Hill, 2003. 6th ed.Slide 38: Source Undetermined

Additional Source Information for more information see: http://open.umich.edu/wiki/CitationPolicy

**********************Fig 6-1.gif*Fig 6-2.gif***Fig 6-1.gif*****************Fig 6-6.gif*Fig 6-7.gif**