2. Evaluation of the Cyanotic Infant Bill Lefkowitz 16 NOV 2000

3. Outline Cyanosis - define and describe Cyanosis - define and describe Terms (PaO 2 v SaO 2 v CaO 2 ) Terms (PaO 2 v SaO 2 v CaO 2 ) Differential of cyanosis Differential of cyanosis The hyperoxia test The hyperoxia test A few etiologies A few etiologies Take home points Take home points Evaluation and intervention Flowchart Evaluation and intervention Flowchart

4. Cyanosis 3g/dL deoxyhemoglobin 3g/dL deoxyhemoglobin Low flow areas with increased oxygen extraction have more deoxyhemoglobin Low flow areas with increased oxygen extraction have more deoxyhemoglobin High flow areas with less extraction should not have enough deoxyhemaglobin to appear cyanotic High flow areas with less extraction should not have enough deoxyhemaglobin to appear cyanotic Under normal circumstances you should not be able to extract enough O 2 to have 3g/dL deoxyhemoglobin running through the tongue and gums (lips OK when cold) Under normal circumstances you should not be able to extract enough O 2 to have 3g/dL deoxyhemoglobin running through the tongue and gums (lips OK when cold)

5. Cyanosis Acro v Central Acrocyanosis Acrocyanosis part of normal transition part of normal transition may last 72hr may last 72hr beware APGAR of 10 beware APGAR of 10 hypoperfused hypoperfused severe anemia severe anemia

6. Cyanosis

7. Cyanosis Cyanosis is dependent on HCT and % Sat Cyanosis is dependent on HCT and % Sat Florescent light makes cyanosis hard to see. Florescent light makes cyanosis hard to see. Except in the extreme, cyanosis is not obvious Except in the extreme, cyanosis is not obvious Any question, check a pulse ox Any question, check a pulse ox

8. RA v. O 2 - Saturations

9. Terms PaO 2 PaO 2 Arterial Oxygen Pressure Arterial Oxygen Pressure Measured on an ABG machine Measured on an ABG machine Oxygen dissolved in plasma Oxygen dissolved in plasma 0.003 ml O 2 /mmHg/dl plasma 0.003 ml O 2 /mmHg/dl plasma SaO 2 SaO 2 Percent Oxygen Saturation Percent Oxygen Saturation Measured by saturation monitor (pulse-Ox) Measured by saturation monitor (pulse-Ox) ~1.34ml O2/g Hb ~1.34ml O2/g Hb

10. PaO 2 and SaO 2

11. Oxyhemoglobin dissociation

12. Terms CaO 2 CaO 2 Oxygen Content of the blood Oxygen Content of the blood bound to Hb + dissolved in plasma bound to Hb + dissolved in plasma 100% saturated 100% saturated Hb 18g/dl Hb 18g/dl 90 mmHg in plasma 90 mmHg in plasma = [1.0*18*1.34]+[0.003*90] = [1.0*18*1.34]+[0.003*90] = [24]+[0.25] = [24]+[0.25] Physiologically, saturations much more important to oxygen content (0.003*600 = 1.8) Physiologically, saturations much more important to oxygen content (0.003*600 = 1.8)

13. CaO 2 Samples NORMAL 95%, Hb 18 PaO2 85 [.95*18*1.34]+[0.003*85] [23]+[0.25]=23

14. CaO 2 Samples HYPEROXIA 100%, Hb 18 PaO2 600 [1.0*18*1.34]+[0.003*600] [24]+[1.8]=26

15. CaO 2 Samples ANEMIA 95%, Hb 10 PaO2 85 [.95*10*1.34]+[0.003*85] [13]+[0.25]=13

16. CaO 2 Samples ANEMIA- HYPEROXIA 100%, Hb 10 PaO2 600 [1.0*10*1.34]+[0.003*600] [13]+[1.8]=15

17. CaO 2 Samples CCHD 75%, Hb 18 PaO2 40 [.75*18*1.34]+[0.003*40] [18]+[0.12]=18

18. CaO 2 Samples CCHD-ANEMIA 75%, Hb 10 PaO2 40 [.75*10*1.34]+[0. 003*40] [10]+[0.12]=10

19. Differential of cyanosis 3g of deoxyhemoglobin/dL (cyanosis) 3g of deoxyhemoglobin/dL (cyanosis) - Not enough oxygen in - Oxygen “mal-absorption” - Too much oxygen out

20. Not enough oxygen in Apnea Apnea neurologic and pharmacologic causes neurologic and pharmacologic causes Diffusion barrier Diffusion barrier RDS, aspiration, pneumonia RDS, aspiration, pneumonia Obstruction Obstruction pneumothorax, head position pneumothorax, head position

21. Oxygen “mal-absorption” Shunting lesions Shunting lesions cardiac cardiac non-cardiac (like PPHN) non-cardiac (like PPHN) Hematologic Hematologic methemoglobinemia methemoglobinemia carboxyhemoglobinemia carboxyhemoglobinemia

22. Too much oxygen out High oxygen consumption High oxygen consumption sepsis sepsis low flow, high extraction low flow, high extraction acrocyanosis acrocyanosis hyperviscosity/polycythemia hyperviscosity/polycythemia extravasated (ie bruising) extravasated (ie bruising) What is the Hyperoxia test?

23. Hyperoxia Test Infant on Room Air, get ABG Infant on Room Air, get ABG Infant on 100% oxygen, get ABG Infant on 100% oxygen, get ABG PaO 2 unchanged = fixed shunt = CCHD PaO 2 unchanged = fixed shunt = CCHD Max PaO 2 <100 = CCHD Max PaO 2 <100 = CCHD Max PaO 2 >200 = No CCHD Max PaO 2 >200 = No CCHD

24. Hyperoxia Test Giving 100% overcomes the diffusion barrier Giving 100% overcomes the diffusion barrier Normal ----------- Normal ----------- Bad Lungs ------- Bad Lungs ------- (diffusion barrier) (diffusion barrier) Shunt ------------- Shunt ------------- Shunt with Bad -- Shunt with Bad -- Lungs Lungs

25. Hyperoxia Test Hyperoxia Proper Hyperoxia Proper Hyperoxia CPAP Hyperoxia CPAP Hyperoxia hyper- ventilation Hyperoxia hyper- ventilation

26. Hyperoxia Test Jones: 1976 Jones: 1976 8/109 with CCHD had PaO 2 > 100mmHg 8/109 with CCHD had PaO 2 > 100mmHg 7/23 without CCHD (bad RDS etc) had PaO 2 < 150mmHg 7/23 without CCHD (bad RDS etc) had PaO 2 < 150mmHg HLHS > 300mmHg HLHS > 300mmHg TGA, TAPVR > 200mmHg TGA, TAPVR > 200mmHg Don’t be fooled by early high PaO 2 s Don’t be fooled by early high PaO 2 s

27. Hyperoxia Test Don’t do the room air part Don’t do the room air part Looking for minimal PaO 2 change from 21% to 100% fiO 2 Looking for minimal PaO 2 change from 21% to 100% fiO 2 Hyperoxia test developed pre pulse-ox Hyperoxia test developed pre pulse-ox With pulse-ox you can tell when PaO 2 s are not changing despite big changes in fiO 2 (for sats that are between 70 and 95%) With pulse-ox you can tell when PaO 2 s are not changing despite big changes in fiO 2 (for sats that are between 70 and 95%) Probably the norm to have some degree of lung disease at the time of the test anyway Probably the norm to have some degree of lung disease at the time of the test anyway

28. Information needed Clinical appearance Clinical appearance “comfortably tachypneic and blue” “comfortably tachypneic and blue” Pulses/perfusion Pulses/perfusion differential, delayed differential, delayed Pulse-Ox/ABG Pulse-Ox/ABG pre and post ductal, max PaO 2 pre and post ductal, max PaO 2 Auscultation Auscultation S2, Murmur S2, Murmur

29. Information needed CXR CXR heart shapes heart shapes snowman = TAPVR 1 snowman = TAPVR 1 boot = pulm atresia, TOF, tricuspid atresia boot = pulm atresia, TOF, tricuspid atresia egg on string = TGA egg on string = TGA pulmonary vascularity pulmonary vascularity EKG EKG axis axis increased or decreased forces increased or decreased forces

30. TAPVR 1 Snowman Snowman 50% type 1 50% type 1 50% snowman 50% snowman venous connection at VV to SVC venous connection at VV to SVC

31. TOF Boot shape Boot shape RVH lifting apex RVH lifting apex loss of PA knob loss of PA knob

32. TGA Egg on a string Egg on a string alignment of PA and Ao narrows the mediastinum alignment of PA and Ao narrows the mediastinum

33. The 6 T’s Total Anomalous Pulmonary Veins Total Anomalous Pulmonary Veins Tetrology of Fallot Tetrology of Fallot Tricuspid Atresia Tricuspid Atresia Transposition Transposition Truncus Arteriosus Truncus Arteriosus Total Acardia

34. Normal Anatomy normal normal

35. PPHN - PDA shunting Pre and post ductal sats Pre and post ductal sats Head and coronaries get well oxygenated blood Head and coronaries get well oxygenated blood

36. Normal Anatomy normal normal

37. PPHN - PFO shunting Head and coronaries get hypoxemic blood Head and coronaries get hypoxemic blood

38. TAPVR

39. TAPVR Type 1 (supracardiac) Type 1 (supracardiac) 50% with snowman 50% with snowman can have UE<LE sats can have UE<LE sats Type 2 (cardiac) Type 2 (cardiac) Type 3 (infracardiac) Type 3 (infracardiac) all can obstruct, infracardiac almost always does all can obstruct, infracardiac almost always does

40. Normal Anatomy normal normal

41. TOF Overriding Aorta Overriding Aorta VSD VSD PS PS RVH RVH

42. Normal Anatomy normal normal

43. Tricuspid Atresia

44. TGA normal normal

45. TGA - no PPHN Comfortably tachypneic (usually big) child with sats in the 50s on room air or oxygen Comfortably tachypneic (usually big) child with sats in the 50s on room air or oxygen

46. TGA - with PPHN TGA and TAPVR type 1 can present with higher sats in then lower extremities than the upper extremities TGA and TAPVR type 1 can present with higher sats in then lower extremities than the upper extremities

47. Normal Anatomy normal normal

48. Truncus Arteriosus

49. Normal Anatomy normal normal

50. Total Acardia Poor prognosis, consider DNR Poor prognosis, consider DNR

51. Flow diagram There are bad acyanotic lesions There are bad acyanotic lesions There are bad cyanotic lesions There are bad cyanotic lesions A ductal dependent lesion is one that depends on the ductus to get adequate blood flow to the pulmonary and systemic circuits, or provide mixing A ductal dependent lesion is one that depends on the ductus to get adequate blood flow to the pulmonary and systemic circuits, or provide mixing PS PS CoA CoA TGA TGA

52. Summary and Take Home Points Check a pulse ox (murmur w/u, suspicion) Check a pulse ox (murmur w/u, suspicion) murmur w/u (š Sx) Pulse-Ox, EKG, 4-point BPs murmur w/u (š Sx) Pulse-Ox, EKG, 4-point BPs Don’t be fooled by a reassuring hyperoxia test if suspicion remains high Don’t be fooled by a reassuring hyperoxia test if suspicion remains high If you think you have a ductal dependent lesion, start prostin (don’t be afraid of prostin) If you think you have a ductal dependent lesion, start prostin (don’t be afraid of prostin)

53. Summary and Take Home Points If a baby presents in shock in the first week (or two) of life think sepsis & ductal dependant lesions & CAH If a baby presents in shock in the first week (or two) of life think sepsis & ductal dependant lesions & CAH Cyanosis w/u includes antibiotics Cyanosis w/u includes antibiotics Make sure your pharmacy carries prostin Make sure your pharmacy carries prostin Don’t be afraid to use it Don’t be afraid to use it Know how to mix it! Know how to mix it!

54. QUESTIONS?