Description:Introduction
Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease, characterized by right ventricular outflow tract (RVOT) obstruction, ventricular septal defect, overriding aorta, and right ventricular hypertrophy . Perioperative cyanotic spells can be triggered by multiple factors, including anesthetic induction, hypovolemia, stress responses, or increased catecholamine release . In such situations, there is an acute increase in right-to-left shunting across the ventricular septal defect (VSD), resulting in profound systemic desaturation.
Cyanotic spells are usually managed with fluid resuscitation, increasing systemic vascular resistance (phenylephrine), reducing pulmonary vascular resistance (oxygenation), and decreasing myocardial contractility/heart rate (beta-blockers like propranolol or esmolol) . However, in severe cases, these standard measures may fail, leading to life-threatening hypoxia. In such scenarios, immediate restoration of pulmonary blood flow is critical to prevent life threatening desaturation & cardiac arrest or to go immediately on CPB.
We present a novel, rapid-responsive AORTO- PULMONARY SHUNT (designed by using two IV Cannula and connector) to create a temporary aorto-pulmonary shunt similar to BTT Shunt, allowing for immediate oxygenation/saturation improvement in a TOF patient experiencing a refractory cyanotic spell. This can done by assistant also & main surgeon can continue in process of establishing CPB.

Case Report
A 5-year-old female child with Tetralogy of Fallot was scheduled for elective total correction. Preoperative echocardiography and CT angiography revealed good-sized branch pulmonary arteries but significant RVOT obstruction at valvular level in main pulmonary artery, necessitating a transannular patch. Additionally, two large major aortopulmonary collateral arteries (MAPCAs) had been coiled preoperatively.
Following routine induction of anesthesia, the patient developed progressive hypoxia with fluctuating saturations, eventually dropping below 20% despite aggressive standard spell management. The anesthesia team attempted fluid resuscitation, 100% oxygenation, deep sedation, and vasoactive support, but the spell persisted, and the patient’s condition deteriorated rapidly.
Recognizing the urgency, the decision was made to proceed with an emergency sternotomy & to put patient on CPB. Time was critical, as CPB setup in a beginner’s hands would take several minutes, and the risk of cardiac arrest was imminent.
Innovative Rescue Approach-AORTO PULMONARY SHUNT : upon opening the pericardium, the heart was found to be severely cyanotic and underfilled main pulmonary artery, confirming that pulmonary blood flow was critically compromised. To immediately restore pulmonary circulation, we employed an innovative approach to augment pulmonary blood flow using our novel AORTO -PULMONARY shunt, constructed from the following simple components:
1. A 14F IV cannula was inserted into the ascending aorta.
2. Another 14F IV cannula was placed into the distal main pulmonary artery.
3. The two cannulas were connected using a standard IV tubing connector, allowing oxygenated blood from the aorta to flow directly into the pulmonary circulation.
This can done by assistant also & main surgeon can continue in process of establishing CPB. Within seconds, oxygen saturation increased from 20% to 70%, and the patient’s hemodynamics stabilized. This rapid stabilization provided crucial time for CPB initiation under controlled conditions. Once CPB was established, the IV cannulas were removed, and total correction was successfully performed with a transannular patch.

Discussion
Perioperative cyanotic spells are life-threatening emergencies in TOF, particularly in cases with severe fixed RVOT obstruction. Conventional spell management is often effective, but in rare situations where the response is inadequate, immediate intervention to restore pulmonary blood flow is critical .
Our AORTO-PULMONARY SHUNT mimics the physiology of a modified Blalock-Taussig-Thomas(BTT) shunt, providing an immediate and temporary systemic-to-pulmonary connection.
The main advantages of this technique(Comparison With Other Interventions below)
include:
a. Speed: Takes few seconds to establish, compared to CPB initiation which takes several minutes.
b. Simplicity: AORTO PULMONARY SHUNT made by using simple article (only two IV cannulas and a connector) requiring no specialized vascular grafts or anastomoses. This can done by assistant also & main surgeon can continue in process of establishing CPB.
c. Universality: Can be performed in any center, even in resource-limited settings where rapid CPB initiation may not be feasible.
d. Reversibility: The shunt can be easily disconnected and removed once CPB is established.

This technique is particularly valuable for surgeons-in-training, where CPB initiation may take longer, increasing the risk of hypoxic injury or cardiac arrest in such critical situations.

Conclusion
This case highlights an innovative, simple, and life-saving AORTO- PULMONARY SHUNT- which we make by using two IV Cannulas for managing refractory perioperative cyanotic spells in TOF patients. As it will take some time to put patient on CPB, meanwhile we can manage the child by this novel innovative AORTO- PULMONARY SHUNT for increasing pulmonary blood flow. This novel innovative AORTO- PULMONARY SHUNT serves as an effective interim approach to stabilize the patient until bypass is established. The AORTO-PULMONARY SHUNT offers an effective bridge to CPB, ensuring patient stabilization , preventing fatal hypoxia and have potential to save many life which otherwise would have been lost on operating table itself.
This AORTO- PULMONARY SHUNT insertion is easily adaptable, achieved in few seconds & can done by assistant also while main surgeon can continue in process of establishing CPB. This should be considered in emergency scenarios where immediate pulmonary blood flow restoration is required.

Abbreviations
CPB
Cardio Pulmonary Bypass
IV
Intravenous Cannula
MAPCAs
Major Aorta Pulmonary Collaterals
TOF
Tetrology of Fallot
VSD
Ventricular Septal Defect
RVOT
Right Ventricular Outflow Tract , Claims:A life-saving temporary AORTO-PULMONARY SHUNT system ( made by using two cannulas and cannula connector) designed for emergency use in patients experiencing critical desaturation due to cyanotic congenital heart defects on operating table before Cardio pulmonary bypass begin.