Effects of Serratus Anterior Plane Block (SAP), Pectoral Nerve Blocks (PECS I-II), and Standard Systemic Analgesia on Early Postoperative Recovery After Coronary Artery Bypass Grafting

Patients meeting the inclusion criteria and providing written informed consent were randomly assigned to one of three parallel study groups using a computer-generated randomization sequence prepared by an independent investigator.

Participants were allocated in a 1:1:1 ratio to:

Group S (Serratus Anterior Plane Block - SAP):

Following coronary artery bypass grafting (CABG), patients were transferred to the cardiovascular intensive care unit (ICU). Within the first 30 minutes after ICU admission, an ultrasound-guided serratus anterior plane (SAP) block was performed using an 8-cm peripheral block needle. After appropriate aseptic preparation of the anterior chest wall, 30 mL of 0.25% bupivacaine was injected into the fascial plane either superficial or deep to the serratus anterior muscle at the level of the fourth rib. All patients additionally received standardized multimodal systemic analgesia.

Group P (Pectoral Nerve Block - PECS I-II):

After transfer to the ICU, patients received an ultrasound-guided PECS I-II block within the first 30 minutes. Following sterile preparation, 15 mL of 0.25% bupivacaine was injected into the interpectoral plane (between pectoralis major and minor muscles) for PECS I, and an additional 15 mL was injected into the plane between pectoralis minor and serratus anterior muscles for PECS II, totaling 30 mL. Standardized systemic analgesia was also administered.

Group C (Control - Standard Systemic Analgesia):

Patients received standardized multimodal systemic postoperative analgesia without any regional nerve block. Postoperative analgesia included scheduled intravenous paracetamol and rescue opioid administration as needed.

Participants and outcome assessors were blinded to group allocation. The anesthesiologist performing the regional block was not blinded. ICU clinicians responsible for extubation decisions were unaware of treatment allocation.

The study primarily evaluated the duration of mechanical ventilation (time from ICU admission to successful extubation within the first 24 postoperative hours). Secondary outcomes included ICU length of stay, postoperative pain intensity (VAS at 0, 4, 8, 12, and 24 hours post-extubation), total rescue opioid consumption (morphine equivalents), time to first mobilization, postoperative nausea and vomiting (PONV), and length of hospital stay.

Inclusion criteria

• Agreeing to participate in the study,
• 20-65 years old
• ASA I-II-III
• Open heart surgery

Exclusion criteria

• Refusal to participate in the study
• 20 years old, over 65 years old
• Pregnancy
• Presence of bleeding diathesis
• Liver or kidney failure
• Receiving effective treatment on immunity
• Immune suppressed
• Those with BMI ≥30