1、NON-CARDIAC SURGERY IN CHILDREN WITH CONGENITAL HEART DISEASE,CHD,8 per 1000 live births million patients in the US with repaired, palliated or unoperated CHD Advances in Mx increasing survival Trend to early repair Anesthetic mx complicated by diversity of CHD and wide spectrum of surgeries perform
2、ed CHD adds significantly to the mortality of non-cardiac surgery,SPECTRUM OF CHD,SPECTRUM OF INTERVENTION,True correction PDA, ASD, some VSD Correction with residua Some VSD, Coartation of the Aorta Correction with sequelae TOF, TGA Complications Arrhythmias or conduction abn. from incisions or sut
3、ures Palliative surgery B-T shunt, PA banding Cath lab interventions Cure or palliation,ISSUES TO RESOLVE,Nature of repair Age and era of repair Ventricular outflow obstruction Ventricular dysfunction Arrhythmias and conduction abnormalities Hypoxemia Pulmonary Hypertension Endocarditis prophylaxis
4、Extracardiac problems Monitoring,NATURE OF THE REPAIR,ANATOMIC LV to aortaRV to pulm arterycirculation in seriescyanosis corrected a) Simple Recon ASD, VSD, PDAtreat as for normal heart b) Complex outflow tract (TOF, AS, PS, coarct)conduits or baffles (PA)septum and AV valve repair,NATURE OF THE REP
5、AIR,2. PHYSIOLOGICAL single or 2 ventriclecirc in seriescyanosis relievedsignificant sequelae a) Two ventricle repair - RV is systemicLV is pulmonary b) Single ventricle TA, HRHS, double inlet/outlet ventricles Venous return directly to PAsuccess: RA to LA pressure grad, n AV valve, vent fn serious
6、potential problems,AGE AND ERA OF REPAIR,The trend since the 80s has shifted to early definitive repair, without prior palliation Also since the 80s TGA is repaired with arterial switch, not atrial.,VENT OUTFLOW OBSTRUCTION,LV: AS, Coarct, Interrupted Ao archfatigue, syncope, chest pain, arrhythmia
7、RV: TOF, PS, conduit (PA/Truncus/TGA with PS), PVOD- conduits calcify and narrow- ischemic, hypertrophied RV- intracardiac defect may relieve pressure,VENTRICULAR DYSFUNCTION,Myocardial dysfunction insidious May not report symptoms History of decreasing exercise tolerance Objective evaluation useful
8、 CAUSES: volume overloadpressure overloadchronic hypoxemiarec/sustained tachycardia,ARRHYTHMIAS,major impact after palliation or repair life threatening in abnormal heartCAUSES: damage during surgerychamber dilatationmyocardial hypertrophymeds, anes agents, electrolytes,ARRHYTHMIAS,Supraventricular
9、and sinus node: - intra-atrial surgery - elevated RA pressure AV node and prox conducting tissue: VSD repair AV septal repair TOF Ventricular: Pressure loaded eg AS Chr RV volume and pressure load eg TOF Tachyarrhythmia and vent dysfn is dangerous,HYPOXEMIA/CYANOSIS,2 causes: - R to L shunt - Admixt
10、ure (Qp:Qs = 1:1 sats = 75-85%) 2 outcomes: - ThromboembolismChr hypoxemia polycythemia viscosity - CoagulopathyCorrelates with HctDue to platelet and factor deficiency,PULMONARY HYPERTENSION,Unrestricted L to R shunt PBF & PAP Affects ventilation Enlarged vessels obstruct airways Enlarged LA venous
11、 congestion Produces structural changes in pulm vessels medial hypertrophy, necrotizing arteritis PVOD PHT (labile vs fixed, severity),ENDOCARDITIS,Prophylaxis for all EXCEPT : Secundum ASD Repaired ASD, VSD, PDA 6 months and no residua Resp flex.bronchoscopy*, BMTs GIT TEE*, endoscopy* GUT circumci
12、sion, urethral cath Cardiac cath, angioplasty,ENDOCARDITIS,Above diaphragm: Ampi or Amoxicillin 50mg/kg (PO 1hr, IV 30m) Clindamycin 20mg/kg (PCN allergic) Cefazolin 25mg/kg (mild PCN sensitivity) Below diaphragm: Ampi 50mg/kg + Gent 1.5mg/kg + Ampi or Amox 25mg/kg 6hr later (high risk) Vanc 20mg/kg
13、 + Gent 1.5mg/kg (PCN allergic),PREOP ASSESSMENT,Concerns on history Failure to thrive, sweating, dyspnea (CCF) Poor exercise tolerance Rec. chest infections PHT Severe AS syncope, lethargy Uncorrected TOF cyanosis, squatting ? Prior surgery eg. Shunts, Fontan etc,PREOP ASSESSMENT,Examination Active
14、/well-nourished vs ill-looking Cyanosis, sweating, tachypnea, dyspnea Venous distension, hepatomegaly Murmurs, crackles and wheezing Check pulses Neurological damage (CPB, paradoxical emboli, and cerebral abscess/infarct) Airway,PREOP ASSESSMENT,Labs: Hct, K ECG: age-related, best evaluated by card.
15、 ECHO: recenttype and severity of lesionventricular functionpulmonary pressure and O2 response Close collaboration with cardiologist invaluable,INDICES OF CRITICAL IMPAIRMENT,Chronic hypoxemia (sat 2:1 LV or RV outflow gradient 50 mmHg Elevated pulmonary vascular resistance Polycythemia (Hct 60%),PR
16、EOP,Limit fasting Cardiac meds; omit diuretic Appropriate premed Endocarditis prophylaxis,GENERAL APPROACH,R to L shunt: Avoid IV air; No N2O IV volumePVR (already low)SVR (phenyl 10mcg/ml 1-4mcg/kg) Inhalslower,L to R shunt:PVR for large shuntinotropy dynamic IV fluid obstructionIVslower,End of Part 1,
