Increased extravascular lung water (EVLW) may increase mortality and morbidity in cardiopulmonary pathology. Many factors can cause increased extravascular lung water and pulmonary edema after cardiac surgery. This includes left ventricular failure, acute mitral regurgitation; systemic inflammatory response post-cardiopulmonary bypass, left to right shunts, transfusion associated acute lung injury, acute respiratory distress syndrome(ARDS) and sepsis.

The clinical assessment of lung water ranges from auscultation to radiological methods to invasive measurements like dye dilution or thermodilution studies.

Lung ultrasonography is the newest modality for noninvasive assessment of extravascular lung water. Lung ultrasound has been validated against auscultation, chest X-rays, CT chest as well as the bedside gold standard, transpulmonary thermodilution in adults.

Critically ill children are more susceptible to complications and worsened outcomes from increased EVLW.

Lung ultrasound correlates with clinical and radiological endpoints, but has not been validated against invasive objective measures like transpulmonary thermodilution.

Evaluation of transpulmonary thermodilution setups in the pediatric population has shown different normal values and cutoffs compared to adults, possibly due to differential rates growth and development.

It is aimed to investigate the correlation of Lung ultrasound based indices of extravascular lung water to invasive measures, assess optimum cutoffs to appropriate clinical endpoints and evaluate their sensitivity and specificity.

Inclusion Criteria:

• aged under 12 years,
• undergoing elective cardiac surgery for cyanotic or acyanotic congenital heart disease,
• Aristotle score ≤9,
• with prior written informed consent

Exclusion Criteria:

• Neonates,
• Children with any chest wall deformity,
• children with known lung disease, active infection,
• those weighing less than 3.5 kg.

Children with cyanotic or acyanotic heart undergoing elective cardiac surgery.