Anesthesia for congenital heart disease.

Case discussion of anesthesia for congenital heart ds

1. CASE PRESENTATION
Chairperson: Dr. RAVI NAGA PRASAD
Moderator: Dr. NEELIMA
Speaker: Dr. SOWJANYA

2. CASE HISTORY
SASANK / 8 YEARS MALE/ 45 Kgs resident of
Himayathnagar, Hyderabad
Was admitted in hospital with presenting complaints of:
● Pain abdomen since 1 day
●Vomitings since 1 day
●Fever since 1 day

3. CLINICAL BACKGROUND
Known case of Congenital Heart Disease diagnosed as TRICUSPID ATRESIA
WITH UNPROTECTED PULMONARY BLOOD FLOW at 3 months of age
with symptoms of Respiratory distress.
Pt. has undergone Pulmonary Artery Banding under Cardiopulmonary
bypass and using cold blood cardioplegic technique at a private hospital.
Intraoperative and postoperative periods were uneventful.
Child was discharged with normal cardiovascular status.
Pt. was on Tab. Aldactone 5mg BD and Tab. Propranolol 10mg OD

4. HISTORY OF PRESENT ILLNESS
Now Pt. presented with Acute Abdomen with provisional
diagnosis of APPENDICULAR PERFORATION.
Pt. has Grade II dyspnoea
Pt. has history of Cyanotic spells but reduced in frequency
after cardiac surgery
No history of palpitations/ orthopnea/ PND
No history of CVA/ seizures/ any other CNS manifestations

5. BIRTH HISTORY: Born to non-consanguinous parents.
Mother had regular Antenatal checkups.
Born at full term by LSCS due to oligohydramnios at a
private hospital. Baby cried immediately after birth.
Birth weight was 2.5 kgs.
Immunized till date as per schedule.
FAMILY HISTORY: not significant .
PERSONAL HISTORY: Mixed diet, normal appetite,
bladder- bowel habits were regular, adequate sleep.

6. GENERAL EXAMINATION
Moderately obese child 8 yrs old and 45 Kgs with
●Central cyanosis
●Clubbing
●Skin having dusky appearance
●Pt. is febrile
●PR: 80/min, regular rhythm and normal volume
All peripheral pulses are felt
●BP: 120/80 mm of Hg, right arm in supine position
●SpO2: 60% on room air

8. SYSTEMIC EXAMINATION
CVS: thoracotomy scar +
No raised JVP
S1 S2 heard, no murmurs
RS: B/L air entry +
P/A: soft, No dissension, rebound tenderness in RIF+,

9. AIRWAY EXAMINATION
Mouth opening : >3 fingers
Mallampatti grade: II
No loose teeth
Thyromandibular joint: normal
Neck extension: normal
Trachea: central

10. ANAESTHETIC MANAGEMENT
In practice one can expect to encounter one
of the 3 types of CHD pts:
●Pt. with an corrected cardiac lesion
●Pts. who have had palliative surgery. Eg;
TOF with B- T shunt
●Pts. with corrected CHD lesion with or
without residual defects.

11. PRE-OPERATIVE EVALUATION
●What is the anatomical change associated with the cardiac
defect and any palliative procedures. This can be done via a
review of all relevant investigations like blood tests,
Radiography, Echocardiography, Catheterization reports.
●Direction and amount of shunt.
●The extent of increase or decrease of Pulmonary blood
flow, if there is increase in PBF is Pulmonary hypertension
present or if there is a decrease in blood flow, is there a
shunt present?

12. ●What is the degree of hypoxia or polycythemia?
●Do any coagulation defects exist or is there evidence
of thromboembolic phenomena?
●Functional status of the patient.
●What associated pathological findings will influence
management?
●Review of drug history: ant-failure therapy,
anticoagulant and anti-arrhythmic agent. These
agents have impact on peri-operative management.
●Other factors such as appropriate counseling for
family.

13. Important associated pathological findings/ complications of
CHD are presence of :
1.CARDIAC FAILURE:
●Dictate the avoidance of agents like Propofol which have
deleterious effect on cardiac output
●Ketamine supports sympathetic tone and results in stable
hemodynamics
●The decreased cardiac output prolongs Inhalational and
Intravenous induction therefore excessive drug
administration is avoided
●There is also risk of poor coronary perfusion and for this
Adrenaline/Phenylephrine should be kept available.

14. 2. PULMONARY HYPERTENSION:
●Defined as mean Pulmonary Artery Pressure (PAP)
>25 mm Hg at rest and >30 mm Hg on exercise in the
presence of equal distribution of blood flow to all lung
segments
●Pulmonary HTN reduces airway compliance and
increases airway resistance, which leads to an
increase in work of breathing
●Pulmonary hypertensive crisis: Pulmonary vascular
resistance increases rapidly & supercedes systemic
Pressure in response to a variety of stimuli including:

15. ●Alveolar hypoxia
●Hypoxia (PaO2 <60 mm Hg)
●Hyperbaric
●Metabolic acidosis
●Activation of sympathetic nervous system by noxious
stimuli & hypothermia.
C/F: syncope, dyspnoea, cyanosis, pallor, bradycardia,
Rt ventricular heave & bronchospasm

16. Treatment strategy for Pul. HTN

17. 3. ARRHYTHMIAS:
●Atrial
●Sub- atrial
●Ventricular ectopic
4. CYANOSIS: common feature of CHD
●Chronic hypoxia increases erythropoetin production which
leads to increase in hemoglobin and hence hematocrit &
blood viscosity
●The increased hemoglobin allows more oxygen delivery
without a sustained increase in cardiac output.

18. ●Above a hematocrit of 65% , complications can arise such as
decreased O2 delivery from red cell rigidity (especially with iron
deficiency) and hyperviscosity leading to cerebral vein & sinus
thrombosis
●The high risk groups for such complications are :
Children < 5 years
Dehydration
Fe deficiency
Fever
●To minimize risk, preoperative fasting should be kept
to minimum and i . v fluid therapy is indicated.

19. Laboratory tests of hemostasis may be defective:
●Prolonged PT & PTT
●Thrombocytopenia
●Platelet dysfunction
●Hypo fibrinogenemia
●Accelerated fibrinolysis
Aspirin is often used to avoid shunt thrombosis and this
should be continued in the peri- operative period as risk
of thrombosis is more than bleeding.

20. APPROACH FOR RISK STRATIFICATION

21. PREMEDICATION
●Sympathetic stimulation due to crying of an anxious &
distressed pt. can increase oxygen consumption and
myocardial work; poorly tolerated in a child with
limited cardiac reserve
●Midazolam in the dose of 0.5 mg/ kg orally or 0.1- 0.25
mg/ kg iv 30 min before surgery

22. INDUCTION
●All commonly used induction agents are well
tolerated depending on the rate & dose of the drug
●SVR & PVR balance should be considered when
using iv agents
●Pts. with poor cardiac function, who require
intropes pre- operatively, may not tolerate
inhalational agents induction and favor the use of
ketamine.

23. INTRA-OPERATIVE PERIOD
●Cyanotic episodes under anesthesia responds to
volume, increase in SVR with alpha agonists such as
phenylephrine or ephedrine
●In these pts pulse oximetry overestimates arterial
oxygen saturation, end- tidal CO2 readings
underestimate PaCO2
●When in doubt, obtain arterial blood gas
pre-operatively for baseline

24. ●“Goal directed fluid therapy” is recommended for
major procedures with substantial blood loss or fluid
shifts
●Avoid fluid & salt overload while avoid hypovolemia
●Ventilation and Oxygenation:
Balance PVR & SVR, avoid PHT
●Extubation: “fast- tract extubation” to avoid
respiratory complications

25. POSTOPERATIVE CONSIDERATIONS
●Pain management is critical factor that must be
considered during intra or postoperative period
●Opioid infusion or patient controlled analgesia
●Even with favorable outcome, pts with CHD coming
for non- cardiac surgery are still under high risk
category after operation