1. Postoperative Care in the Patient With Congenital Heart Disease UTHSCSA Pediatric Resident Curriculum for the PICU

2. General Principles  Patient homeostasis Early – declining trends do not correct themselves Early – declining trends do not correct themselves Late – time can be important diagnostic tool Late – time can be important diagnostic tool “The enemy of good is better”

3. Specific Approaches  Cardiovascular principles  Approach to respiratory management  Pain control/sedation  Metabolic/electrolytes  Infection  Effects of surgical interventions on these parameters NO PARAMETER EXISTS IN ISOLATION

4. Cardiovascular Principles  Maximize O 2 delivery/ O 2 consumption ratio Oxygen delivery: Oxygen delivery: Cardiac Output Cardiac Output Ventilation/Oxygenation Ventilation/Oxygenation Hemoglobin Hemoglobin

5. Maximizing Oxygen Delivery Metabolic acidosis is the hallmark of poor oxygen delivery

6. Maximizing Oxygen Delivery OXYGENDELIVERYOXYGENCONTENTCARDIACOUTPUTX =

7. O 2 Content = Saturation(O 2 Capacity)+(PaO 2 )0.003  Oxygen Capacity = Hgb (10) (1.34)  So.. Hemoglobin and saturations are determinants of O 2 delivery Hemoglobin and saturations are determinants of O 2 delivery Maximizing Oxygen Delivery Cardiac Output

8. Gidding SS et al 1988 y=-0.26(x)+38R=0.77S.E.E.=1.6 Maximizing Oxygen Delivery Cardiac Output

9. Stroke Volume Contractility Contractility Diastolic Filling Diastolic Filling Afterload Afterload Heart rate Physiologic Response Non-physiologic Response Sinus vs. junctional vs. paced ventricular rhythmCardiacOutputStrokeVolume HeartRate = X

10. Maximizing Oxygen  Oxygen consumption Decreasing metabolic demands Decreasing metabolic demands Sedation/ paralysis Sedation/ paralysis Thermoregulation Thermoregulation

11. Ventilator Strategies  Respiratory acidosis/hypercarbia  Oxygenation Physiology of single ventricle/shunt lesions Physiology of single ventricle/shunt lesions Oxygen delivery! Oxygen delivery!  Atelectasis – 15-20 cc/kg tidal volumes.  PEEP, inspiratory times

12. Ventilator Strategies: Pulmonary Hypertension  Sedation/neuromuscular blockade  High FiO2 – no less than 60% FiO2  Mild respiratory alkalosis pH 7.50-7.60 pH 7.50-7.60 pCO 2 – 30-35 mm Hg pCO 2 – 30-35 mm Hg  Nitric Oxide

13. Ventilator Strategies: Pulmonary Hypertension Precipitating Event -Cold stress -Suctioning -Acidosis Metabolic Acidosis Hypercapnia Increased PVR Decreased Pulmonary Blood Flow Decreased LV preload RV dysfunction Central Venous Hypertension Hypoxemia Low output Ischemia

14. Pain Control/Sedation  Stress response attenuation  Limited myocardial reserve – decreasing metabolic demands  Labile pulmonary hypertension  Analgesia/anxiolysis

15. Pain Control/Sedation Opioids  MSO4 – Gold standard: better sedative effects than synthetic opioids Cardioactive – histamine release and limits endogenous catecholamines Cardioactive – histamine release and limits endogenous catecholamines  Fentanyl/sufentanyl Less histamine release Less histamine release More lipid soluble – better CNS penetration More lipid soluble – better CNS penetration

16. Pain Control/Sedation Sedatives  Chloral hydrate Can be myocardial depressant Can be myocardial depressant Metabolites include trichloroethanol and trichloroacetic acid Metabolites include trichloroethanol and trichloroacetic acid  Benzodiazepines Valium/Versed/Ativan Valium/Versed/Ativan

17. Pain Control/Sedation Muscle relaxants  Depolarizing – Succinylcholine Bradycardia ( ACH) Bradycardia ( ACH)  Non-depolarizing Pancuronium – tachycardia Pancuronium – tachycardia Vecuronium – shorter duration Vecuronium – shorter duration Atracurium Atracurium “spontaneously” metabolized “spontaneously” metabolized Histamine release Histamine release

18. Pain Control/Sedation Others:  Barbiturates – vasodilation, cardiac depression  Propofol – myocardial depression, metabolic acidosis  Ketamine – increases SVR  Etomidate – No cardiovascular effects

19. Fluid and Electrolytes  Effects of underlying cardiac disease  Effects of treatment of that disease

20. Cardiopulmonary Bypass  “Controlled shock”  Loss of pulsatile blood flow Capillary leak Capillary leak Vasoconstriction Vasoconstriction Renovascular effects Renovascular effects Renin/angiotensin Renin/angiotensin  Cytokine release  Endothelial damage and “sheer injury”

21. Cardiopulmonary Bypass Stress Response SIRS Microembolic Events Renal Insufficiency Fluid Administration Hemorrhage Capillary Leak Syndrome Feltes, 1998 Lung Fluid Filtration =  [( )-  ( )] Microvascular Hydrostatic Pressure Microvascular Oncotic Pressure

22. Circulatory Arrest  Hypothermic protection of brain and other tissues  Access to surgical repair not accessible by CPB alone  Further activation of SIRS/ worsened capillary leak.

23. Fluid and Electrolyte Principles  Crystalloid Total body fluid overload Total body fluid overload Maintenance fluid = 1500-1700 cc/m 2 /day Maintenance fluid = 1500-1700 cc/m 2 /day  Fluid advancement: POD 0 : 50-75% of maintenance POD 0 : 50-75% of maintenance POD 1 : 75% of maintenance POD 1 : 75% of maintenance Increase by 10% each day thereafter Increase by 10% each day thereafter

24. Fluid and Electrolyte Principles Flushes and Cardiotonic Drips Remember: Flushes and Antibiotics = Volume Remember: Flushes and Antibiotics = Volume UTHSCSA protocol to minimize crystalloid: Standard Drip Concentration Mix in dextrose or saline containing fluid to optimize serum glucose & electrolytes Sedation: (Used currently as carrier for drips) MSO4 2cc/hr = 0.1 mg/kg/hr Fentanyl 2 cc/hr = 3 mcg(micrograms)/kg/hr Cardiotonic medications: Dopamine/Dobutamine50 mg/50 cc Epi/Norepinephrine0.5 mg/50 cc Milrinone5 mg/50 cc Nipride (Nitroprusside)0.5 mg/50 cc Nitroglycerin50 mg/50 cc PGEI500 mcg/50 cc

25. Fluid and Electrolyte Principles  Intravascular volume expansion/ Fluid challenges Colloid – osmotically active Colloid – osmotically active FFP FFP 5% albumin/25% albumin 5% albumin/25% albumin PRBC’s PRBC’s HCT adequate: 5% albumin (HR, LAP, CVP) HCT adequate: 5% albumin (HR, LAP, CVP) HCT inadequate: 5-10 cc/kg PRBC HCT inadequate: 5-10 cc/kg PRBC Coagulopathic: FFP/ Cryoprecipitate Coagulopathic: FFP/ Cryoprecipitate Ongoing losses: CT and Peritoneal frequently = 5% albumin Ongoing losses: CT and Peritoneal frequently = 5% albumin

26. Metabolic Effects  Glucose Neonates vs. children/adults Neonates vs. children/adults Hyperglycemia in the early post-op period Hyperglycemia in the early post-op period

27. Metabolic Effects  Calcium Myocardial requirements Myocardial requirements Rhythm Rhythm Contractility Contractility Vascular resistance Vascular resistance NEVER UNDERESTIMATE THE POWER OF CALCIUM!

28. Calcium/inotropes Sarcoplasmic Reticulum cAMP-Dependent PK Ca Phosphodiesterase AdenylateCyclase Regulatory G Protein Na Alpha 1 Beta 1 DAG IP3 Na K SR

29. Metabolic Effects  Potassium Metabolic acidosis Metabolic acidosis Rhythm disturbances Rhythm disturbances

30. Thermal Regulation As a sign to watch, and an item to manipulate…  Perfusion  Junctional ectopic tachycardia  Metabolic demands Oxygen consumption Oxygen consumption Infection Infection

31. Infection  Routine anti-staphylococcal treatment

32. Effects of Surgical Interventions  Cardiopulmonary Bypass vs. Non-Bypass Fluids and electrolytes Fluids and electrolytes  Modified ultrafiltration  Types of anatomic defects Overcirculated – increased blood volumes preoperatively Overcirculated – increased blood volumes preoperatively Undercirculated – reperfusion of area previously experiencing much reduced flow volumes. Undercirculated – reperfusion of area previously experiencing much reduced flow volumes.

33. Summary  Optimize oxygen delivery by manipulation of cardiac output and hemoglobin  Sedation and pain control can aid in the recovery  Appreciate effects of cardiopulmonary bypass and circulatory arrest on fluid and electrolyte management  Tight control of all parameters within the first 12 hours; after that time, patients may be better able to declare trends that can guide your interventions.