1 / 68

Cardiopulmonary Bypass in Infants and Children

Cardiopulmonary Bypass in Infants and Children. 세종병원 박 천 수. The Child Is Not A Small Adult. The Difference from Adults. What’s the difference?. - In the response to and the management of CPB -. Smaller circulating volume Higher oxygen consumption (metabolic) rate

sydnee
Télécharger la présentation

Cardiopulmonary Bypass in Infants and Children

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Cardiopulmonary Bypass in Infants and Children 세종병원 박 천 수

  2. The Child Is Not A Small Adult

  3. The Difference from Adults

  4. What’s the difference? - In the response to and the management of CPB - • Smaller circulating volume • Higher oxygen consumption (metabolic) rate • Reactive pulmonary vascular bed • Presence of intracardiac and extracardiac shunting • Immature organ systems • Altered thermoregulation • Poor tolerance to microemboli

  5. Circulating Volume

  6. Discrepancy - Circulating volume vs. priming volume -

  7. Discrepancy - Circulating volume vs. priming volume -

  8. Cardiopulmonary Bypass

  9. Schematic Diagram

  10. Components • Cannulae : arterial/ venous • Tubing : diameter/ length • Blood pump : roller/ centrifugal • Reservoir • Oxygenator : membrane/ bubble/ film • Arterial filter • Supplements : cardioplegic circuitry/ untrafiltration circuitry/ vent or cardiotomy sucker circuitry

  11. Components • Cannulae : arterial/ venous • Tubing : diameter/ length • Blood pump : roller/ centrifugal • Reservoir • Oxygenator : membrane/ bubble/ film • Arterial filter • Supplements : cardioplegic circuitry/ untrafiltration circuitry/ vent or cardiotomy sucker circuitry Priming

  12. Low Priming - Bloodless CPB -

  13. Low Priming - Bloodless CPB -

  14. Sejong Neonatal Circuitry

  15. Flow rate Metabolic rate

  16. Myocardial Protection

  17. Immature Heart Free Fatty Acid Glucose Ann ThoracSurg 2003;75:1668-77

  18. Physiologic Differences

  19. Total Body Oxygen Consumption More tolerable Ann Surg 1950;132:531-9

  20. Immature Heart Mature Immature SeminThoracCardiovascSurgPediatr Card SurgAnnu 2004;7:141-54

  21. Immature Heart More Tolerable ?

  22. Immature Heart More Tolerable ? • Yes ! in normal heart • No !! in diseased heart

  23. Immature Heart • Immature heart with CHD • Exposure to hypoxia • Exposure to volume overload • Exposure to pressure overload • Intrinsically ↓amount of ATP (~50%) • ↑ calcium sensitivity, ↓ antioxidant defense mechanism  Not tolerable !!

  24. Myocardial Protection • Hypothermia • Cardioplegia

  25. Myocardial Protection • Hypothermia : “ Main Stay ” • Protective effect • ↓ metabolic demand • stopping electromechanical work • ↓ loss of metaboilc substrate • Deleterious effect • “cooling contracture” : release of intracellular calcium • Avoid cold perfusion before X-clamp or use of warm induction CPS • Hypocalcemic priming

  26. Myocardial Protection Ann ThoracSurg 2003;75:1668-77

  27. Myocardial Protection Rapid rewarming : ↑ ↑ CPB temperature Septal temperature Rectal temperature J ThoracCardiovascSurg 1988;96:414-22

  28. Myocardial Protection • Maintenance of myocardial hypothermia • Systemic hypothermia : cold perfusion • Cold cardioplegic solution • Topical cooling • Cold ambient temperature in the OR : Air conditioning • Degree of hypothermia : needs for reduced flow and expected duration of myocardial ischemia • Mild : 30 ~ 34℃ • Moderate : 25 ~ 30 ℃ • Deep : 15 ~ 22 ℃

  29. Myocardial Protection

  30. Myocardial Protection • Cardioplegia • Therapeutic arrest of the contractile apparatus and all electrical activity of the myocytes • Maintenance of hypothermia • Cardioplegia: adressing the problems related to “Ischemia – reperfusion injury” • Type of cardioplegia  Lack of consensus !!

  31. Myocardial Protection * From AATS 2003 and STS 2004

  32. Myocardial Protection • General consent in CPS • Blood = Crystalloid • Blood > Crystalloid : preop stress, longer ischemic time expected • Hypocalcemic • Add Mg • High osmotic pressure • Lower infusion pressure

  33. Myocardial Protection • Modifications in CPS • Dosage : Single shot vs. multidose • Administration • Antegrade : indirect/ direct • Retrograde • Add substrate or oxygen • Warm induction/ warm shot

  34. Sejong General Hospital • Type of cardioplegic solution • Crystalloid • Del Nido • Bretschneider • Blood : mixing crystalloid + O2 blood = 4:1 • Dosage • One-shot: BSA ⅹ 600 ml • Multidose: initial 20~30ml/kg  10ml/kg • Infusion pressure: ~ 40mmHg (perdiatric) • Plasma solution (base solution) : 1000ml • Potassium : 26 mEq • Mannitol : 3.25g • 1%Lidocaine : 130mg • Sodium bicarbonate : 13mEq • 50% Magnesium sulfate : 2g • 20% Glucose 10ml: 2g

  35. Cerebral Protection

  36. Brain • Immature brain • Critical period : GA 6months ~ 6month after birth • Neurologic injury • Intrinsic pathology • Injury related to preexsting conditions • Cyanosis • Heart failure • Injury during surgery • Adverse effect of CPB • Use of cirulatory discontinuation

  37. Cerebral Blood Flow • Autoregulation : maintain blood flow Cerebral Blood Flow (ml/100gmin) Mean arterial pressure (mmHg)

  38. Cerebral Blood Flow - Temperature - Moderate HCPB Deep HCPB Circulation 1989;80(supplI):I209-I215

  39. Cerebral Blood Flow - Temperature - Circulation 1989;80(supplI):I209-I215

  40. Cerebral Metabolic Rate - Temperature - J ThoracCardiovascSurg 1991;101:783-94

  41. Cerebral Metabolic Rate - Temperature - 10 CMRO (ml/100g/min) 5 Temperature (℃) 0 10 20 30 40 J ThoracCardiovascSurg 1991;101:783-94

  42. Cerebral Blood Flow - Minimal Pump Flow Rate - Ann ThoracSurg 1993;56:1366-72

  43. Acid-Base (CO2) Management • Temperature ↓ • blood pH alkalotic • cerebral vascular resistance ↑ • switched major buffering system : (NH3-, HCO3-)  alpha imidazole ring in Histidine • Cerebral blood flow : distribution of cold perfusate • intracellular pH (pHi) • Intracelluar enzymatic function Cerebral blood flow ↓

  44. Acid-Base (CO2) Management

  45. Acid-Base (CO2) Management • During mild or moderate hypothermia • Alpha-stat vs. pH-stat ~ no difference • Combination during deep hypothermia pH-stat during cooling phase • alpha-stat just before circulatory discontinuation

  46. Aortic Arch Surgery

  47. Deep Hypothermic Bypass - DHCA vs. regional perfusion -

  48. Deep Hypothermic Bypass - DHCA vs. regional perfusion - ? • Optimal perfusion flow: ? • Optimal perfusion pressure: ? • Is it really neuroprotective?

  49. Deep Hypothermic Bypass - DHCA vs. regional perfusion - - Survey ; CHS in North America - < J ThoracCardiovascSurg 2009;137:803-6

  50. Deep Hypothermic Bypass - DHCA vs. regional perfusion - - Survey ; CHS in North America - J ThoracCardiovascSurg 2009;137:803-6

More Related