Chapter 6 Part 1 Fall 2024 PDF

Chapter 6: Part 1 To fully comprehend this subject, student must understand: – How oxygen is transported from lungs to tissues – Oxyhemoglobin dissociation curve and its clinical significance – How various oxygen transport calculations are used to identify patient’s cardiac and ven...

Chapter 6: Part 1 To fully comprehend this subject, student must understand: – How oxygen is transported from lungs to tissues – Oxyhemoglobin dissociation curve and its clinical significance – How various oxygen transport calculations are used to identify patient’s cardiac and ventilatory status – Major forms of tissue hypoxia – How carbon dioxide is transported from tissues to lungs © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Chapter 6: Oxygen Transport Understanding of oxygen and carbon dioxide transport essential to study of pulmonary physiology and to clinical interpretation of arterial and venous blood gases – Arterial Blood Gas (ABG) – Venous Blood Gas (VBG) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Introduction Radial-arterial blood gas stick Arterial Blood Gases (ABGs) – blood test used to provide information that helps assess and manage a patient’s respiratory and metabolic acid/base balance and to assess adequacy of oxygenation. (Used with permission from the author: T. Des Jardins, WindMist LLC) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-1. © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Oxygen Transport Transport of oxygen between lungs and cells of body is function of blood and heart Oxygen is carried in blood in two forms: 1. Dissolved oxygen in blood plasma 2. Chemically bound (attach) to hemoglobin (Hb) that is encased in erythrocytes or RBCs © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Oxygen Dissolved in the Blood Plasma Dissolve means Quantity of oxygen that that gas maintains dissolves in plasma is its precise function of Henry’s molecular structure law – In this case, O2 – Amount of gas that dissolves in liquid at given temperature is proportional to partial pressure of gas In this case, plasma © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oxygen Dissolved in the Blood Plasma Approximately.003 mL of O2 will dissolve in 100 mL of blood for every 1 torr of PO2 – Thus, PaO2 of 100 mmHg = 0.3 mL – 02 Dissolved Formula: (P02 mmHg) x (0.003 ml / 100 ml blood / 1 mmHg) (P02 x 0.003) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oxygen Dissolved in the Blood Plasma Written as 0.3 volumes percent (vol%) Vol% represents amount of O2 (in mL) in 100 mL of blood © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oxygen Dissolved in the Blood Plasma Example: – 10 vol% of O2 means there are 10 mL of O2 in 100 mL of blood – Relatively small percentage of oxygen is transported in form of dissolved oxygen © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Oxygen Bound to Hemoglobin Most oxygen that diffuses into pulmonary capillary blood rapidly moves into RBCs and chemically attaches (bound) to hemoglobin Each RBC contains approximately 280 million Hb molecules © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Oxygen Bound to Hemoglobin Normal adult hemoglobin (Hb A) consists of: – Four heme groups Pigmented, iron- containing nonprotein portions of hemoglobin molecule – Four amino acid chains (polypeptide chains) that collectively constitute globin (protein) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oxygen Bound to Hemoglobin When 02 molecules combine with Hb, the 02 molecule will no longer exert a pressure © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 02 bound to Hb 02 unbound to Hb Oxyhemoglobin Reduced hemoglobin – Hemoglobin bound with Hemoglobin not bound oxygen with oxygen Also called – Also known as: 1. Oxyhemoglobin 1. Deoxyhemoglobin 2. Combined hemoglobin 2. Uncombined 3. Oxygenated hemoglobin hemoglobin 3. Reduced Hemoglobin © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Oxygen Bound to Hemoglobin Normal adult male Hb value: – 14 to 16 grams percent or g% Normal adult female Hb value: – 12 to15 g percent Normal Hemoglobin Range: – 12 to 16 gm/100 ml blood – 12 to 16 g percent – 12 to 16 grams per deciliter – Gram percent of hemoglobin (g% Hb) – Grams per deciliter (g/dL) Deciliter = 100 milliters Remember – Vol% represents amount of O2 in mL in 100 mL of blood – Thus, g% represents amount of 02 in grams in 100 ml of blood © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Quantity of Oxygen Bound to Hemoglobin Each g% Hb can carry 1.34 mL of oxygen at 100% capacity – Thus, if Hb level is 15 g percent, and if Hb is fully saturated, approximately 20.1 vol% of O2 will be bound to Hb © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Quantity of Oxygen Bound to Hemoglobin At normal PaO2 of 100 torr, however, Hb saturation (SaO2) is only approximately 97 percent due to the following three normal physiologic shunts: – Thebesian venous drainage into left atrium – Bronchial venous drainage into pulmonary veins – Alveoli that are under ventilated Dead space ventilation © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Quantity of Oxygen Bound to Hemoglobin Thus, amount of arterial oxygen in preceding equation must be adjusted to 97 percent A) B) C) 02 Bound formula (1.34 x Hb x Sa02) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Content (C02) To determine total The following case amount of oxygen in study summarizes 100 mL of blood, the calculations required following must be to compute added together: individual’s total – Dissolved oxygen oxygen content – Oxygen bound to hemoglobin © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Content of Arterial Blood CaO2 = oxygen content of arterial blood Ca02 = (Bound to Hb) + (Dissolved 02) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Anemic Patient 27-year-old woman Long history of anemia – Decreased hemoglobin concentration Showing signs of respiratory distress Respiratory rate of 36 breaths/minute Heart rate of 130 beats/minute Blood pressure of 155/90 mmHg Hemoglobin concentration of 6 g percent PaO2 of 80 torr SaO2 90 percent © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Anemic Patient Based on this information, patient’s total oxygen content is computed as follows: © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Case Study: Anemic Patient 2. Oxygen bound to hemoglobin: 6 g% Hb x 1.34 (O2 bound to Hb factor) 8.04 vol% O2 (at SaO2 of 100%) 8.04 vol% O2 x 0.90 SaO2 7.236 vol% O2 © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Case Study: Anemic Patient 3. Total oxygen content: 7.236 vol% O2 (bound to hemoglobin) + 0.24 vol% O2 (dissolved O ) 2 7.476 vol% O2 (total amount of O /100 mL of blood) 2 © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Anemic Patient Notes: – Patient’s total arterial oxygen content is less than 50 percent of normal – Patient’s hemoglobin concentration is very low Primary mechanism for transporting oxygen – Once problem is corrected, respiratory distress should no longer be present © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Content Total calculations of: – Oxygen content of arterial blood (CaO2) – Oxygen mixed venous blood (CvO2) – Oxygen pulmonary capillary blood (CcO2) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Content of Arterial Blood CaO2 = oxygen content of arterial blood Normal: 17 to 20 vol% © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Content of Mixed Venous Blood CvO2 = oxygen content of mixed venous blood Normal: 12 to 16 vol% © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Content of Pulmonary Capillary Blood CcO2 = oxygen content of pulmonary capillary blood Remember PA02? © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Oxyhemoglobin (HbO2) Dissociation Curve Also known as HbO2 equilibrium curve Part of nomogram that graphically illustrates percentage of hemoglobin chemically bound to oxygen at each oxygen pressure © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Clinical Significance of the Flat Portion of the Curve PO2 can fall from 60 As Hb moves through to 100 torr and A-C system, significant hemoglobin will still partial pressure be 90 percent difference continues to saturated with exist between alveolar oxygen gas and blood – Excellent safety zone – Even after most O2 has transferred – Enhances diffusion of O2 © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Plateau = safety zone – Starting from Pa02 up to Pa02 level? Steep = danger zone – Begin when Pa02 = ? © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Clinical Significance of the Flat Portion of the Curve Increasing PO2 beyond 100 torr adds very little O2 to blood – Dissolved O2 only (PO2 x 0.003 = dissolved O2) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Clinical Significance of the Steep Portion of the Curve Reduction of PO2 below 60 torr causes rapid decrease in amount of O2 bound to hemoglobin – However, diffusion of oxygen from hemoglobin to tissue cells enhanced © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  P50 Point of reference on oxyhemoglobin dissociation curve Represents partial pressure at which hemoglobin is 50 percent saturated with oxygen Normally, approximately 27 torr © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oxyhemoglobin Dissociation Curve P50 represents partial pressure at which hemoglobin is 50 percent saturated with oxygen – When oxyhemoglobin dissociation curve shifts to right, P50 increases – When oxyhemoglobin dissociation curve shifts to left, P50 decreases © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-5.  Factors that Shift Oxygen Dissociation Curve When curve shifts to right, P50 increases – 02 Affinity to Hb decrease When curve shifts to left, P50 decreases – 02 Affinity to Hb increases © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Factors that Shift Oxygen Dissociation Curve pH Temperature Carbon dioxide 2,3-bisphosphoglycerate (2,3-BPG) – RBC anaerobic glycolysis – Hypoxia - ↑ – Anemia - ↑ – PH ↑ then ↑ – Stored Blood - ↓ Fetal hemoglobin (Hb F) Carbon monoxide hemoglobin (affinity?) (carboxyhemoglobin or COHb) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Oxyhemoglobin Dissociation Curve © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-6. © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Delivery Total amount of oxygen Total oxygen delivery delivered or transported to peripheral tissues (DO2) calculated as dependent on: follows: – Body’s ability to oxygenate blood – Hemoglobin concentration – Cardiac output Normal: 1000 ml02/min © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Delivery DO2 decreases in D02 = QT x Ca02 response to: D02 = C.O. x Ca02 – Low blood oxygenation – C.O. = HR x SV Low PaO2 – Ca02 = (Hb x 1.34 x Sa02) Low SaO2 + (Pa02 x 0.003) Low hemoglobin concentration Low cardiac output D02 = (HR x SV) x [(Hb x 1.34 x Sa02) + (Pa02 x 0.003)] © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Total Oxygen Delivery DO2 increases in response to: – Increased blood oxygenation Increased PaO2 Increased SaO2 Increased hemoglobin concentration Increased cardiac output © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Pulmonary Shunting Portion of cardiac output that moves from right side to left side of heart without being exposed to alveolar oxygen (PAO2) Clinically, can be subdivided into: – Absolute shunt Also known as true shunt – Relative shunt Also known as shunt-like effects © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Absolute Shunt Grouped under two major categories: – Anatomic shunts Exists when blood flows from right side of heart to left side without coming in contact with alveolus for gas exchange – Capillary shunts © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Pulmonary Shunting © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-14.  Absolute Shunt In healthy lung, normal anatomic shunt of approximately 3 percent of cardiac output – Normal shunting caused by nonoxygenated blood completely bypassing alveoli and entering: Pulmonary vascular system by means of bronchial venous drainage Left atrium by way of thebesian veins © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Common Causes of Absolute Shunting Congenital heart disease Intrapulmonary fistula Vascular lung tumors © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Capillary Shunts Capillary shunting commonly caused by: – Alveolar collapse or atelectasis – Alveolar fluid accumulation – Alveolar consolidation © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Relative Shunt When pulmonary capillary perfusion is in excess of alveolar ventilation, relative or shunt-like effect said to exist Common causes: – Hypoventilation – Ventilation/perfusion mismatches Chronic emphysema, bronchitis, asthma – Alveolar-capillary diffusion defects © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Pulmonary Shunting © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-14.  Venous Admixture End result of pulmonary shunting: – Venous admixture Mixing of shunted, non-reoxygenated blood with reoxygenated blood distal to alveoli Downstream in pulmonary venous system See Figure 6-15 © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Venous Admixture Venous admixture occurs when reoxygenated blood mixes with non- reoxygenated blood © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-15.  Venous Admixture When venous Process continues admixture occurs, until: shunted, non- – PO2 throughout all reoxygenated blood plasma of newly mixed gains oxygen molecules blood is in equilibrium while, simultaneously, – All hemoglobin reoxygenated blood molecules carry same loses oxygen molecules number of oxygen molecules © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Shunt Equation © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Shunt Equation Clinical Information Needed PB PaO2 PaCO2 PvO2 Hb PAO2 FIO2 © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Motorcycle Accident Victim 38-year-old man is on volume-cycled mechanical ventilator on a day when barometric pressure is 750 torr Patient is receiving FIO2 of.70 The following clinical data are obtained: – Hb 13 g percent © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Motorcycle Accident Victim The following clinical data are obtained: – PaO2 50 torr (SaO2 = 85 percent) – PaCO2 43 torr – PvO2 37 torr (SvO2 = 65 percent) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Motorcycle Accident Victim With this information, can calculate patient’s PAO2, CcO2, CaO2, and CvO2 torr © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Case Study: Motorcycle Accident Victim © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Case Study: Motorcycle Accident Victim © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Case Study: Motorcycle Accident Victim © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Case Study: Motorcycle Accident Victim Based on previous calculation, patient’s degree of pulmonary shunting can now be calculated: Q = CcO – CaO s 2 2 QT CcO2 – CvO2 = 18.735 – 14.957 18.375 – 11.434 = 3.778 7.301 = 0.517 © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Clinical Significance of Pulmonary Shunting 30 percent abnormality – Potentially life- threatening © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. HYPOXEMIA VERSUS HYPOXIA © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Hypoxemia Abnormally low arterial oxygen tension in the blood Frequently associated with hypoxia – Inadequate level of tissue oxygenation Although presence strongly suggests tissue hypoxia, does not necessarily mean absolute existence of tissue hypoxia – E.g., reduced level of oxygen in arterial blood may be offset by increased cardiac output © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Hypoxemia © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Table 6-11.  NBRC © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Hypoxia Low or inadequate oxygen for aerobic cellular metabolism Characterized by tachycardia, hypertension, peripheral vasoconstriction, dizziness, and mental confusion © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Hypoxia Four main types: – Hypoxic hypoxia – Anemic hypoxia – Circulatory hypoxia – Histotoxic hypoxia © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Hypoxia © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Table 6-12.  Hypoxia © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Table 6-12.  Hypoxia © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Table 6-12.  Hypoxia © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Table 6-12.  Cyanosis Blue-gray or purplish discoloration seen on mucous membranes, fingertips, and toes – Blood in these areas contain at least 5 g% of reduced hemoglobin E.g. If patient’s normal Hb is 16 g%, when does cyanosis occur? © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Cyanosis May appear whenever blood contains at least 5 g% of reduced hemoglobin © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Figure 6-16.  Polycythemia When using hemoglobin level, polycythemia is present when hemoglobin level is greater than: – 18.5 g percent in men Normal = 14 to 16 g percent – 16.5 g percent in women Normal = 12 to 15 g percent © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Clinical Connection 6-2: Polycythemia Abnormally high RBC count Identified when Chronic low 02 levels by hematocrit (HCT) increase 02 carrying capacity is greater than: Hallmark: – 52 percent in men – Elevated hematocrit or Normal = 45 percent hemoglobin – 48 percent in Problem: ↑ viscosity women HCT reaches 55 to 60% Normal = 42 percent Lead to left & right hypertrophy and cor pulmonale (rt failure) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Formulas 02 Dissolved Formula –(P02 mmHg) x (0.003 ml / 100 ml blood / 1 mmHg) –(P02 x 0.003) Vol% -02 ml / 100 mL of blood Oxygen Bound to Hemoglobin -1.34 x Hb x S02 Total Oxygen Content C02 = (Bound to Hb) + (Dissolved 02) C02 = (1.34 x Hb x S02) + (0.003 x P02) © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.  Formulas Oxygen Delivery (D02) Total 02 content x QT [(1.34 x Hb x S02) + (0.003 x P02)] x(SV x HR) Classic Shunt Equation Cyanosis Patient’s normal HB – 5 g% Hb – 5 g% © 2013 Delmar Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part.