Clinical Research Directory

In SAPB; the needle is advanced in-plane from caudally cephalad at the midaxillary line at the level of the fourth rib with 45-degree angle, targeting the plane between the latissimus dorsi and serratus muscles. SAPB block will be performed Bilaterally. After confirmation that the needle tip is in the correct plane by injecting 2 ml of saline, 20 ml of 0.25% bupivacaine hydrochloride \[Maracine prepared by adding an equal volume (1:1) of normal saline (0.9%) to 0.5% bupivacaine\]will be injected, with intermittent aspiration to confirm neither air nor blood in the needle.

In TPVB; the needle is advanced in parasagittal plane over the transverse processes of the T4 and T5 vertebrae, about 2.5 cm lateral to the spinous processes, just deep to the superior costotransverse ligament but superficial to the parietal pleura. TPVB will be performed bilaterally. After confirmation that the needle tip is in the correct plane by injecting 2 ml of saline, 20 ml of 0.25% bupivacaine \[Maracine prepared by adding an equal volume (1:1) of normal saline (0.9%) to 0.5% bupivacaine\] will be injected, with intermittent aspiration to confirm no air or blood in the needle.

Patient will receive IV fentanyl infusion just before skin incision, which will be stopped when cardiopulmonary bypass (CPB) is on, then resumed after weaning form CPB and continued till the end of the surgery.500µg fentanyl will be mixed with 50 ml 0.9% normal saline in 50 ml syringe (10 µg /ml).Infusion rate will be determined according to a dose of 1µg /kg/h.