Even though Erector Spinae Plane (ESP) Block is shown to be efficient in cardiac surgery, the Combine Serratus Anterior Plane (CSAP) Block is still controversial if it has an efficient analgesic effect for sternotomy and drain tube pain relief. This study aims to compare ESP block and CSAP block for postoperative analgesia in coronary bypass surgery patients.

Acute postoperative pain after cardiac surgery originates various surgical procedures that may cause pain including the incision of tissues, sternotomy, the separation of bone-joint structures, the severity and duration of these applications, the use of chest tubes, and the patient's personal inflammatory may affect the response to these stimuli. Postoperative pain is a critical risk factor for the development of pulmonary and cardiovascular complications such as atelectasis, cardiac ischemia, and arrhythmias. Researchers claim that adding techniques to iv drugs, such as thoracic epidural anesthesia, paravertebral block, or erector spinae plane block (ESP) to multimodal analgesia regimens positively affect recovery. Although the efficacy of ESP block in providing postoperative analgesia has been demonstrated in many studies, there is no study comparing CSAP and ESP block in cardiac surgery.

Inclusion Criteria:

• Adult patients who will undergo coronary artery bypass grafting surgery with median sternotomy

Exclusion Criteria:

• Emergency surgeries
• Patients with allergic reactions to anesthesia and analgesia drugs to be used
• Patients who do not want to participate in the study voluntarily
• Severe systemic disease (kidney, liver, pulmonary, endocrine)
• Substance abuse history
• History of chronic pain
• Psychiatric problems and communication difficulties
• Patients who need revision due to hemostasis in the postoperative period
• Patients with severe hemodynamic instability due to infection, heavy bleeding, etc.