High-dose Opioid Versus Opioid-sparing Anaesthesia in Cardiac Surgery

Patients in the OSA group was administrated with 0.5 to 1 mcg·kg-1 sufentanil and received PIFB combined with RSB after anesthetic induction. Patients in the control group were recommended to receive 2 to 3 mcg·kg-1 opioid-based sufentanil. PIFB was conducted at the T2 to T5 levels under ultrasound guidance. Each side received 20 ml 0.3% ropivacaine containing 2.5 mg dexamethasone. Bilateral RSB was conducted after the PIFB and the needle was inserted into the plane between the rectus abdominal muscle and its posterior sheath using an in-plane approach. After verifying needle placement, 15 ml 0.3% ropivacaine containing 2.5 mg dexamethasone was delivered to each side. In the control group, patients received no procedure and were administrated with traditional anesthetic protocol. Patients received continuous intravenous sufentanil (50 to 100 mg) and tropisetron (5 to 10 mg) at 2 ml·h-1 for the first 48 hours after surgery.