Patients undergoing arthroscopic shoulder surgery often experience moderate to severe postoperative pain. Various medical treatments are employed to provide analgesia for these patients. The advancement of regional anesthesia techniques has made possible to both reduce the use of narcotic analgesics and provide long-term pain management benefits.

The Serratus Posterior Superior Intercostal Plane Block (SPSIPB) was first described in 2023 by Serkan Tulgar et al. Cadaveric studies and dermatomal analyses in patients have demonstrated its ability to provide analgesia in the back, neck, shoulder, axilla, and lateral thoracic regions.

Even though patients undergoing shoulder surgery benefit from the block; once the duration of a single-shot block wears off, they may experience severe pain again. The aim of this study is to investigate the analgesic effects of a single-shot SPSIPB compared to continuous infusion provided by placing a catheter in this region.

The hypothesis of this study: In arthroscopic shoulder surgery, the continuous application of the serratus posterior superior intercostal plane block using a catheter will result in lower pain scores, reduced opioid consumption, and improved patient satisfaction compared to single-shot application.

Inclusion Criteria:

• Aged between 18-80 years
• No bleeding diathesis
• Classified as ASA I-II-III

Exclusion Criteria:

• Patients who do not provide consent
• Patients with coagulopathy
• History of allergy or intoxication to local anesthetic agents
• Patients with advanced organ failure
• History of neuropathic disease
• Patients with mental retardation
• Presence of infection at the injection site
• Conditions in which regional anesthesia is contraindicated
• Pediatric patients and those over 80 years of age
• Pregnant patients