anesthetic management in cyanotic CHD

1. ANESTHETIC
CONSIDERATIONS IN
TRICUSPID ATRESIA
& TRANSPOSITION
OF GREAT VESSELSDr.Verdah Sabih
PGT Anesthesia
Holy family Hosp.Rwp

2. INTRODUCTION:
Tricuspid atresia :
 complete agenesis of
tricuspid valve without
any direct communication
b/w RA & RV
 3% of CHD
 3rd most common cause
of cyanotic CHD
 An ASD or VSD is always
present
 Extra cardiac anomalies
present in 20%

3. ETIOLOGY:
Almost always congenital  Characterized by:
 Small RV
 Large LV
 Small VSD &PDA
 Diminished pulmonary
circulation
 cyanosis

4. PATHOPYSIOLOGY:
 Due to tricuspid agenesis, the blood cannot flow
from the RA to the RV.Blood ultimately cannot enter
the lungs.
 Instead, the blood passes through ASD between
the RA &LA. In the LA, it mixes with oxygenated
blood returning from the lungs. This mix of
oxygenated and de-oxygenated blood is then
pumped out into the body. This causes oxygen level
in the blood to be lower than normal.
 The lungs receive blood either through a VSD
between the right and left ventricles, or through
ductus arteriosus that connects the pulmonary
artery to the aorta.

6. MANAGEMENT:
 Primarily surgical
 Either an operation to increase pulmonary blood
flow (shunt)
 Or to decrease pulmonary blood flow (pulmonary
artery band)
 Fontan’s procedure

7. ANESTHETIC GOALS:
 Anesthetic management is very challenging
 Profound cyanosis may impair non invasive
monitoring of oxygen saturation
 Nitrous oxide or sevoflorane used for inhalational
induction followed by a change to narcotics based
anesthetic once intravenous access established
 MAP must be kept up to maintain shunt patency
 Careful rehydration necessary despite fluid deficit
preoperatively
 Maintain the hemostasis of PVR to SVR ratio &
ventricular performance

8. LV
PRELOA
D
HR RHYTHM CONTRA
CTILITY
SVR PVR
Maintain
or higher
rate
Maintain
orhigher
rate
Maintain
sinus
rhythm
Maintain
or
increase
maintain
or

9.  Early tracheal extubation & spontaneous ventilation
are desirable
 Positive inotropic drugs (dopamine) with or without
vasodilators (nitroprusside)are often required to
optimize cardiac output & maintain low PVR
 Monitoring the CVP to assess the intravascular fluid
volume & to detect sudden impairment of LV
function & increased PVR
 Peak & mean airway pressure must be maintained.

10. TRANSPOSITION OF GREAT ARTERIES:
 5% of CHD
 10% of all neonatal cyanotic CHD
 Failure of truncus arteriosus to go spiral so that
aorta arises from the anterior portion of RV & the
pulmonary artery from LV

12. PATHOPHYSIOLOGY:
 Due to complete seperation of pulmonary &
systemic circulation , systemic venous blood
traverses RA,RV, aorta & systemic circulation
 Pulmonary venous blood traverses LA,LV,
pulmonary arteries & lungs
 Circulation is parallel instead of normal in series
circulation
 Survival is posible only if there is communication
between the 2 circulations in the form of a
VSD,ASD or PDA

13. SIGNS & SYMPTOMS:
 Cyanosis (in the 1st week of life)
 Tachypnea
 Respiratory distress
 Non specific systolic ejection murmur
 Congestive heart failure (tachypnea, tachycardia,
sweating & poor feeding)
 Right axis deviation &RV hypertrophy on ECG
 Cardiac shadow “egg shaped with a narrow stalk”
on CXR

14. TREATMENT:
 Immediate management involves creating
intracardiac mixing or increasing the degree of
mixing
 Infusions of PG E1 to maintain patency of DA
 Ballon atrial septostomy
 Oxygen administration to decrease PVR & increase
pulmonary blood flow
 Diuretics & digoxin for CHF
 Mustard’s/ senning’soperation(venous switch)
 Arterial switch procedure

15. ANESTHETIC MANAGEMENT:
 Doses & rates of IV administered drugs have to
decreases(distribution of drugs with minimal dilution
to heart & brain)
 Onset of inhaled anesthesia delayed(small amount
reaches systemic circ.)
 Induction & maintenance are accomplished with
ketamine combined with muscle relaxants to
facilitate tracheal intubation
 Ketamine can be supplemented with opiods or
benzodiazepines for maintenance
 Nitrous oxide-limited application

16.  Potential cardio depressant effects of volatile
anesthetics– not used
 Selection of muscle relaxant to avoid histamine-
induced changes in systemic BP----- Pancuronium
used(inc. HR & systemic BP)
 Dehydration must be avoided during perioperative
period(inc. hematocrit--- inc incidence of cerebral
venous thrombosis)
 Prophylaxis for thrombosis & dysarhythmias