The rare combination of tetralogy of Fallot, biliary atresia, and CMV infection is an uncommon aspect of this case.

Based on anatomical bases, BA is categorized according to the degree and kind of obstruction. The majority of the time, BA is either complete (Japanese/Anglo-Saxon type III, 73%) or subcomplete (type IIb, 18%), with types IIa and I (6% and 3%, respectively) and “distal” BA being rare. In addition to being isolated, biliary atresia can also be linked to other congenital abnormalities such as intestinal atresia, absence of retro hepatic vena cava, renal malformations, poly splenia, situs inversus, and cardiac defects such PDA, ASD, and VSD [2,8].
It is a prevalent cause of surgical cholestatic jaundice in newborns, and in underdeveloped nations like ours, Kasai's hepato-portoenterostomy is still the only treatment performed during the first three months of life, reducing the need for eventual liver transplant in the future. The addition of CMV infection further reduces the prognosis in these infants due to impaired immunity [9].

Preoperative evaluation is recommended for infants with untreated cyanotic congenital heart disease who are scheduled for significant non-cardiac surgery, as they are always at high risk. Perioperative management of infants with uncorrected TOF posted for noncardiac surgery is difficult because of the long-term effects of hypoxia and decreased pulmonary blood flow, which lead to significant physiologic alteration and neurological sequelae. Cyanotic episodes are typically caused by either a reduction in Systemic vascular resistance (SVR) or an infundibular spasm, or spasm of the cardiac muscle in the Right Ventricular Outflow Tract (RVOT) region as a result of sympathetic activation. Beta blockers like propranolol or esmolol are used to treat infundibular spasm, whereas α-adrenergic agonists like phenylephrine or norepinephrine and intravenous fluids are used to address any drop in SVR. Because it increases SVR, which reduces right-to-left shunting, ketamine is the recommended induction drug in TOF.

Mitigating increased myocardial oxygen consumption requires lowering sympathetic activation and using dosages of midazolam between 0.008 and 0.01 mg/kg. Avoiding hypothermia, stress reactions to pain, acidosis, hypercarbia, hypoxia, and increases in intrathoracic pressure can help prevent pulmonary hypertension. In order to diagnose arrhythmias and tachycardia, intraoperative ECG monitoring is crucial. Avoiding dehydration is advised.

Pain management is crucial because elevated sympathetic activity brought on by pain can precipitate a cyanotic episode during the perioperative phase. For pain management, we administered fentanyl boluses of 1 mcg/kg during surgery and a paracetamol infusion afterward.

In our scenario IV opioid was the mainstay analgesic agent. Regional anesthesia was avoided due to the altered hepatic physiology. Bradycardia induced by traction on the Inferior vena cava (IVC) and liver and peritoneum were managed with Atropine IV. In order to prevent hypothermia, the operating room was kept at a comfortable temperature, and the infant was completely draped. Care was taken to ensure that the IV line was clear of air bubbles as they have the potential to cause fatal paradoxical embolism due to right-to-left shunting.

Thus, it follows that babies with congenital cardiac abnormalities and viral infections need to be carefully inspected and treated according to their individual needs.