HEMODYNAMIC ASSESSMENT CARDIAC CATHETERIZATION LABORATORY William Hellenbrand MD

HEMODYNAMIC ASSESSMENT: CARDIAC CATHETERIZATION LABORATORY William Hellenbrand MD Director, Pediatric Cardiology Morgan Stanley Children’s Hospital of New York - Presbyterian Columbia University Medical Center Komansky Center for Children’s Health Cornell University Medical Center

CARDIAC CATHETERIZATION • • Cardiac output Shunt & Resistance Oxygen transport Pressure-Volume loops

FICK PRINCIPLE • The amount of flow through an organ or any circuit may be determined if • 1 - that organ consumes or secrets a given substance • 2 - the concentration of that substance can be measured as it enters and leaves the organ • 3 - The total amount of the substance consumed or secreted can be measured per unit time ∆S/∆t C 2 S – C 1 S

FICK PRINCIPLE

OXYGEN IN BLOOD • When oxygen is exposed to blood it exists in 2 forms l Bound to hemoglobin Each gram of Hgb is capable of binding 1. 36 ml O 2. Therefore if the Hgb is 15 gm/100 ml then the maximal amount of oxygen(Capacity) that can be taken up by Hgb is 20. 4 ml/100 ml(Vol%)

OXYGEN IN BLOOD • When oxygen is exposed to blood it exists in 2 forms(cont) • In solution in plasma – At body temperature of 370 , there is. 00003 ml of O 2 per one ml of plasma at a partial pressure of oxygen of 1 mm Hg(1 torr) Thus the solubility coefficient of oxygen in plasma is 0. 00003 ml/ml/mm Hg Therefore the amount of dissolved oxygen in plasma is equal to. 003(PO 2)

OXYGEN IN BLOOD • Oxygen capacity = Hgb(gm/100 ml)*1. 36 ml O 2/gm = ml O 2/100 ml (Vol%) • Oxygen saturation = proportion of O 2 actually combined with hemoglobin to the total capacity • Oxygen content = Capacity*Saturation +. 003*PO 2 = ml/100 ml (Vol%)

OXYGEN CONSUMPTION • VO 2 = VIFIO 2 - VEFEO 2 • If RER is 1 then VI = VE and all you need to measure is VEFEO 2 • RER = VCO 2 / VO 2 – RER is close to 1 with carbohydrate metabolism – RER may be as low as 0. 7 with mostly fat metabolism – Standard nomograms assume RER of 0. 9

Oxygen Consumption

CARDIAC OUTPUT SYSTEMIC BLOOD FLOW Qs = VO 2 Cao. O 2 - Cmv. O 2 Qp = VO 2 Cpv. O 2 - Cpa. O 2 If there is no shunt Qp = Qs

SHUNT CALCULATIONS • Qs = VO 2 Cao. O 2 - Cmv. O 2 • Qp = VO 2 Cpv. O 2 - Cpa. O 2 • Qep = VO 2 Cpv. O 2 - Cmv. O 2

SHUNT CALCULATIONS • SIMPLE SHUNT – Ql-r = Qp - Qs – Qr-l = Qs - Qp • BIDIRECTIONAL SHUNT – Ql-r = Qp - Qep – Qr-l = Qs - Qep

RESISTANCE TO FLOW • Poiseuille equation Q = ∆Pπr 4 8 nl 1 = πr 4 R 8 nl ∆P = pressure drop r = radius n = viscosity l = length of tube Q = ∆P R R = ∆P Q

RESISTANCE • SVR = AO(MEAN) - RA(MEAN) Qs • PVR = PA(MEAN) - LA(MEAN) Qp

SYSTEMIC OXYGEN TRANSPORT (SOT) SOT = Q X X OXYGEN CONTENT [(1. 36 X Hgb X O 2 SAT) + (. 003 X PO 2)]

SYSTEMIC OXYGEN TRANSPORT (SOT) SOT = Q X [(1. 36 X Hgb X O 2 SAT) + (. 003 X PO 2)] Anemic Hypoxia: Hgb Acute compensation Q Chronic compensation Hgb SOT

SYSTEMIC OXYGEN TRANSPORT (SOT) SOT = Q X [(1. 36 X Hgb X O 2 SAT) + (. 003 X PO 2)] Hypoxic Hypoxia: 02 SAT SOT Acute compensation Q SOT Chronic compensation Hgb, Q SOT

SYSTEMIC OXYGEN TRANSPORT (SOT) SOT = Q X [(1. 36 X Hgb X O 2 SAT) + (. 003 X PO 2)] Stagnant Hypoxia: Q SOT Hgb, 02 SAT SOT (Low Cardiac Output) Compensation

VSD 80/50 M=65 95 70 80/40 M=60 80 80 M=8 M=6 70 80/6 85

VSD Room Air • Hgb = 10. 0 Vol% • V 02 = 150 ml/min/m 2 • Saturations – – – Svc Ra Rv Pa Ao = 70 = 85 = 80 = 95 • Pressures – – – Ra = 6(mean) Rv = 80/6 Pa = 80/40 60(mean) La = 8(mean) Ao = 80/50 65(mean)

VSD Room Air • Capacity = 1. 36*10 = 13. 6 • Contents = – – Ao =13. 6*. 95=12. 9 Mv = 13. 6*. 70=9. 5 Pa = 13. 6*. 80=10. 9 Pv = 13. 6*. 95=12. 9 • �� S(a-v)02 difference = 3. 4 • P(a-v)02 difference = 2. 0 • Qp = 150/2. 0 – = 7. 5 l/min/m 2 • Qs = 150/3. 4 – = 4. 4 l/min/m 2 • Ql-r = 7. 5 -4. 4=3. 1 • Qp/Qs = 7. 5/4. 4=1. 7 • PVR =(60 -8)/7. 5 =6. 9 • SVR =(65 -6)/4. 4=13. 4

VSD f. I 02 = 1. 0 • Hgb = 10. 0 Vol% • V 02 = 150 ml/min/m 2 • Saturations – – – Svc Ra Rv Pa Ao = 75 (45) = 80 = 94 = 95 (85) = 100 (600) • Pressures – – – Ra = 6(mean) Rv = 80/6 Pa = 80/40 60(mean) La = 8(mean) Ao = 80/50 65(mean)

VSD f. I 02 = 1. 0(PO 2 not included) • Capacity = 1. 36*10 = 13. 6 • Contents = – – Ao =13. 6*1. 0=13. 6 Mv = 13. 6*. 75=10. 2 Pa = 13. 6*. 95=12. 9 Pv = 13. 6*1. 0=13. 6 • �� S(a-v)02 difference = 3. 4 • P(a-v)02 difference = 0. 7 • Qp = 150/0. 7 – = 21. 4 l/min/m 2 • Qs = 150/3. 4 – = 4. 4 l/min/m 2 • Ql-r = 21. 4 -4. 4=17. 0 • Qp/Qs =21. 4/4. 4=>4/1 • PVR =(60 -8)/21. 4 =2. 4 • SVR =(65 -6)/4. 4=13. 4

VSD f. I 02 = 1. 0(PO 2 included) • Capacity = 1. 36*10 = 13. 6 • Contents = – – Ao =13. 6*1. 0+1. 8=15. 4 Mv = 13. 6*. 75+. 15=10. 4 Pa = 13. 6*. 95+. 25=13. 2 Pv = 13. 6*1. 0+1. 8=15. 4 • �� S(a-v)02 difference = 5. 0 • P(a-v)02 difference = 2. 2 • Qp = 150/2. 2 – = 6. 8 l/min/m 2 • Qs = 150/5. 0 – = 3. 0 l/min/m 2 • Ql-r = 6. 8 -3. 0=3. 8 • Qp/Qs = 6. 8/3. 0=2. 3 • PVR =(60 -8)/6. 8 =7. 6 • SVR =(65 -6)/3. 0=20. 0

VSD • P 02 not included • Qp = 150/0. 7 – = 21. 4 l/min/m 2 • Qs = 150/3. 4 – = 4. 4 l/min/m 2 • Ql-r = 21. 4 -4. 4=17. 0 • Qp/Qs =21. 4/4. 4=>4/1 • PVR =(60 -8)/21. 4 =2. 4 • SVR =(65 -6)/4. 4=13. 4 • P 02 included • Qp = 150/2. 2 – = 6. 8 l/min/m 2 • Qs = 150/5. 0 – = 3. 0 l/min/m 2 • Ql-r = 6. 8 -3. 0=3. 8 • Qp/Qs = 6. 8/3. 0=2. 3 • PVR =(60 -8)/6. 8 =7. 6 • SVR =(65 -6)/3. 0=20. 0

VALVE AREA CALCULATION

OXYGEN DISSOCIATION CURVE

PRESSURE-VOLUME LOOPS

P-V LOOPS

P-V LOOPS Pump Failure

P-V LOOPS