Congenital Heart Disease Greg Gordon MD Updated 2012 Version Training for Career in Pediatric Cardiac Anesthesia Specific Fellowship: Rare Suggested training (US & UK): •Pediatric Anesthesia: 12 months •Adult Cardiac Anesthesia: 6 months •Pediatric Cardiac Anesthesia: 6 months •Pediatric Critical Care: 6 months Baum V & De Souza DG. Pediatric Anesthesia 17:407, 2007 White MC & Murphy TWG. Pediatric Anesthesia 17:421, 2007 • PDA ligations • Murmurs preop • CHD patients for noncardiac surgery Adults with CHD in US today 2,140,000 Growing 5% per year Cahalan MK. Anesthetic Management of Patients with Heart Disease. IARS 2003 Review Course Lectures 3 y/o with TOF s/p right BTS For dental restorations •Turns blue with crying •Scheduled to undergo cardiac repair in 3 months •SpO2 93 •Systolic ejection murmur •Slight clubbing of fingers •Hct 52 Tammy (Recent oral board case) 5 y/o for T&A Systolic murmur • VSD • Needs surgical closure • Cardiologist recommended T&A first Victor 11 y/o with tricuspid atresia s/p Fontan procedure For scoliosis repair •Temporary BTS at age 3 weeks •Modified Fontan at age 3 years •Meds: digoxin, captopril •SpO2 88 on RA, 98 in O2 •P 67, BP 99/42 •First degree AV block Fran Objectives Participants will be able to more intelligently discuss: • Newborn heart and lungs • Initial evaluation the child’s heart • Pathophysiology of selected CHDs • Anesthetic implications of CHD The Newborn Heart CHOP “Duct Busters” Provide service to 17 area NICUs Send team of 2 each surgeons anesthesia providers (attending + CRNA) nurses Operate within 24 - 48 hours Monday – Friday No weekends Reimbursement exceeds other cardiac services Susan Nicholson and Gould DS et al: Pediatrics 2003 112:1298-1301 The Newborn Heart Foramen Ovale Functional closure first hours as LAP > RAP Probe-patent 50% of 5-year-olds 25% of 20-year-olds Paradoxical embolus The Newborn Heart Ventricular tissue •Fewer myocytes •Greater proportion of connective tissue •Relative RVH So: •Decreased compliance •More sensitive to preload The Newborn Heart •Near peak of Starling curve •Stroke volume relatively fixed Normally near peak of Starling curve •C.O. relatively heart rate dependent Stroke volume relatively fixed C.O. relatively heart rate dependent The Newborn Heart ++ Newborn myocardium derives relatively high fraction of activator Ca from the extracellular pool, so Beware Ca channel blockers The Preterm Infant Heart More sensitive to depressant effects of inhaled agents Decreased response to catecholamines Relatively high PVR persists Pulmonary vasculature more sensitive to vasoconstriction by: Hypoxia Acidosis Hypercarbia CHD Pearl murmur in newborn = benign disease Initial evaluation of child’s heart History: To determine •Level of function •CHF Initial evaluation of child’s heart History - cyanosis •Turn blue? •At rest? •When crying? •Passes out? •Stops playing and squats Initial evaluation of child’s heart History - CHF Run around like crazy? Like sibs? Or tends to be quiet, slow? Infant – feeding behavior: Slow to finish bottle? Sweats when nursing? Eyes puffy in the morning? Initial evaluation of child’s heart Physical exam •Listen to heart first when/if infant quiet (warm stethoscope) •First concentrate on S1 and especially S2 Louder than normal? Split normally? •Systolic murmur: Starts after or obscures S1? •Diastolic murmur? •Widely radiating murmur? •Palpate liver •BP in arm and leg •Tongue - cyanosis CHD Pearl Sudden CHF in ‘healthy’ 10-day-old = complicated coarct General Approach to CHD Patient 1. Define cardiovascular pathology 2. Predict pathophysiology 3. Determine hemodynamic goals 4. Anticipate emergency treatments Cahalan MK. Anesthetic Management of Patients with Heart Disease. IARS 2003 Review Course Lectures Don’t worry Almost any anesthetic technic may be used in any CHD patient if the anesthesiologist understands •the pathophysiology of the lesion and •the pharmacology of the drugs employed. Normal Neonate SVC RA m=2 1 week 60 PV 99 LA m=4 65 RV LV 30/3 MPA 30/12 m=18 65 65 80/5 99 99 Ao 80/50 Some basic definitions physiologic L to R shunt = lungs to lungs shunt Blood that is returning to the heart from the lungs is recirculated back to the lungs without going out to the rest of the body. Some basic definitions physiologic R to L shunt = body to body shunt Blood that is returning to the heart from the body is recirculated directly back to the body without going to the lungs to be oxygenated. Some basic definitions effective pulmonary blood flow= body to lungs flow Blood that is returning to the heart from the body that is actually directed to the lungs to be oxygenated. Some basic definitions Nonrestrictive VSD VSD large enough that pressure equalizes in the two ventricles (no pressure gradient can be maintained) LV pressure = RV pressure Premature 1 week old 28 weeks EGA SVC RA PV LA 96 65 RV LV 65/10 65/12 65 MPA 65/30 96 Ao PDA 80 92 65/25 to R arm & head To L arm MHMC PDA ligation CHD Pearl blue newborn + no airway or breathing problem + quiet heart = decreased PBF lesion (TOF) Tetralogy Of Fallot Most common cyanotic lesion NB: cyanosis plus quiet heart Diminished pulmonary blood flow Ao ejection click Hypercyanotic “tet” spells tachypnea, pallor, LOC, less murmur Tammy 3 y/o with TOF s/p right BTS 1. Define cardiovascular pathology 2. Predict pathophysiology 3. Determine hemodynamic goals 4. Anticipate emergency treatments Tammy Tetralogy Of Fallot Essentially a duality: 1. severe RVOT obstruction plus 2. nonrestrictive VSD With anatomic consequences: 1. RVH 2. Overriding aorta And physiologic consequences 1. R to L shunt 2. Diminished pulmonary blood flow Tammy Tetralogy of Fallot SVC 40 96 RA LA RV LV m=5 m=4 85/6 MPA 15/10 40 40 85/5 85 50 Ao 85/45 Tetralogy Of Fallot s/p right BTS? Blalock-Taussig Shunt Tammy Thomas-Blalock-Taussig Shunt Vivien Thomas Alfred Blalock Helen Taussig Vivien Thomas, Partners of the Heart, 1998 and Something the Lord Made - Best Made-for-TV Movie, 2004 November 29, 1944 Thomas-Blalock-Tuassig Dr. Blalock does the Blalock (Johns Hopkins) Systemic to Pulmonary Shunts Tetralogy Of Fallot Maintain adequate tissue oxygenation 1. Avoid increasing O2 demand 2.Maintain SVR, systemic BP 3.Minimize PVR Avoid dehydration, especially if polycythemic Oral premed/induction midazolam + ketamine Tammy Free written board answer: Speed of induction: R->L shunt • Inhalational: slower • IV: faster L->R shunt • Inhalational: maybe faster • IV: slower But probably not clinically important Tanner et al. Anesth Analg 64:101, 1985 Beware: blunted chemoreceptor response to Tammy hypoxemia Beware: VD:VT may be 0.6 Tammy And increase with •start of mechanical ventilation •too much PEEP •hypovolemia ETCO2 << PaCO2 Tetralogy Of Fallot Minimize R->L Shunt MAINTAIN SVR •ketamine •phenylephrine Tammy Tetralogy Of Fallot Minimize RVOT obst & PVR •oxygen •beta blocker ready Maybe: •nitroglycerin •phentolamine •tolazoline •prostaglandin E1 •nitric oxide Tammy Tetralogy Of Fallot And of course: •No Air in lines Maybe no N2O and infective endocarditis prophylaxis Tammy Infective Endocarditis Prophylaxis Infective endocarditis prophylaxis for dental procedures is reasonable only for patients with underlying cardiac conditions associated with the highest risk of adverse outcome from infective endocarditis. Wilson W, Taubert KA et al. AHA Guidelines. Prevention of Infective Endocarditis. Circulation 116:1736-54, 2007 Infective Endocarditis Prophylaxis Recommended Unrepaired cyanotic CHD, including palliative shunts and conduits. Circulation 116:1736, 2007 Infective Endocarditis Prophylaxis Recommended CHD completely repaired with prosthetic material or device less than 6 months ago. Circulation 116:1736, 2007 Infective Endocarditis Prophylaxis Recommended Repaired CHD with residual defect(s) at or near a prosthetic patch or device. Circulation 116:1736, 2007 Infective Endocarditis Prophylaxis Recommended Prosthetic material in a valve. Previous infective endocarditis. Valvulopathy after transplant. Circulation 116:1736, 2007 Infective Endocarditis Prophylaxis Recommended For patients with the above conditions, prophylaxis is reasonable for all dental procedures that involve manipulation of gingival tissue or the apical region of teeth or perforation of the oral mucosa. Wilson W, Taubert KA et al. AHA Guidelines. Prevention of Infective Endocarditis. Circulation 116:1736-54, 2007 Infectious Endocarditis Prophylaxis NOT Recommended Any form of CHD not listed above Local injection -> noninfected tissue Shedding deciduous teeth Bleeding/trauma to lips, oral mucosa Circulation 116:1736, 2007 Tetralogy Of Fallot infective endocarditis prophylaxis and maintain SVR Tammy Tetralogy Of Fallot Treatment of Tet Spell •Knee-chest position •O2 •Morphine 0.1-0.2 mg/kg IM,IV •Phenylephrine gtts : increase systolic BP 20-40 mmHg •Beta blockade, e.g. propanolol: titrate to 0.1 mg/kg •ABG: NaHCO3 if necessary •Surgery CHD Pearl blue newborn + no airway or breathing problem + hyperactive heart = TGA (Recent oral board case) 5 y/o for T&A Systolic murmur • VSD • Needs surgical closure • Cardiologist recommended T&A first Victor Newborn VSD Most common lesion 2/3rds close spontaneously Small VSD Definite murmur Will probably close Large VSD No murmur No problems Home with Mom CHF symptoms by 4-8 weeks VSD nonrestrictive SVC 98 60 96 RA m=6 90/8 90/35 m=12 80 RV MPA LA LV 90/10 94 88 94 Ao 90/60 Nonrestrictive VSD L->R shunt Pulmonary to System Flow Ratio QP:QS = SaO 2 – SvO2 __________ SpvO2 – SpaO2 = 94 - 60 _______ 98 - 88 = 3.4:1 Victor Nonrestrictive VSD Besides, of course: •No Air in lines Maybe no N2O and infectious endocarditis prophylaxis Victor Proper management of the physiologic abnormalities is more important than the choice of specific anesthetic and pharmacologic approaches. Nonrestrictive VSD Maintain PVR Normal ventilation (paCO2 = 40’s) FIO2 < 1 Lower SVR better Major inhalational agents Thiopental, propofol Victor 11 y/o with tricuspid atresia s/p Fontan procedure For scoliosis repair •Temporary BTS at age 3 weeks •Modified Fontan at age 3 years •Meds: digoxin, captopril •SpO2 88 on RA, 98 in O2 •P 67, BP 99/42 •First degree AV block Fran Tricuspid Atresia 3rd most common cyanotic CHD 1. TOF 2. TGA Type IB most common •Small VSD (and RV) •PS 20% extracardiac abnormalities •GI •Musculoskeletal Cyanosis •Mixing in LA •Decreased PBF •Spells Fran Modified Bidirectional Modified Age 5 years 16/10 16/12 88/6 11 y/o with tricuspid atresia s/p Fontan procedure Potential problems during scoliosis repair Hypoxemia 1. Hypovolemia 2. Low PBF CHF 1. Volume shifts 2. Anemia 3. Hypertension Paradoxical embolus Thrombosis Vena cavae RA Pulmonary arteries Fran 11 y/o with tricuspid atresia s/p Fontan procedure Goals during scoliosis repair Monitor RA pressure •RA catheter •Maintain starting pressure Maintain systemic BP near baseline Minimize myocardial depressants NO AIR IN LINES No N2O Relatively high FIO2 Normal Hct Fran Age 5 years 16/10 16/12 88/6 For more cool stuff about CHD check out the lesson and fun Quiz at http://greggordon.org/edu/ped/chd1.htm Now we can more intelligently discuss: • Newborn heart and lungs • Initial evaluation the child’s heart • Pathophysiology of selected CHD • Anesthetic implications of CHD