Serratus Posterior Superior Intercostal Plane (SPSIP) Block Versus Intercostal Nerve (ICN) Block in Patients Undergoing Uniportal-VATS.

Serratus Posterior Superior Intercostal Nerve (SPSIP) Block Versus Intercostal Nerve (ICN) Block in Patients Undergoing Uniportal Video-Assisted Thoracic Surgery (Uniportal-VATS): a Randomized Controlled Trial

This study aims to assess the effectiveness of the Serratus Posterior Superior Intercostal Plane (SPSIP) block compared to the Intercostal Nerve (ICN) block for postoperative pain control, reduction of opioid analgesic consumption, minimization of postoperative respiratory complications, and enhancement of patient satisfaction (measured using the QoR-15 index) in patients undergoing Uniportal Video-Assisted Thoracic Surgery (Uniportal VATS).

Patients enrolled in the study will be divided into two groups: the SPSIP group and the ICN group. Patients in the SPSIP group will receive the Serratus Posterior Superior Intercostal Plane (SPSIP) block , while those in the ICN group will receive the Intercostal Nerve (ICN) block. Both blocks will be performed at the end of surgery: the SPSIP block will be administered by the attending anesthesiologist (Investigator 1) under ultrasound guidance immediately after skin closure and before extubation, while the ICN block will be performed by the surgeon under direct vision immediately before skin closure.

All patients will receive 1000 mg of paracetamol and 30 mg of ketorolac at the end of surgery, during skin closure. Upon arrival in the recovery room, each patient will be connected to a patient-controlled analgesia (PCA) pump containing an opioid-based solution. Patients reporting a Numeric Pain Rating Scale (NPRS) score greater than 4 during postoperative reassessments, despite PCA use, will be administered a rescue analgesic dose of 1000 mg of paracetamol (repeatable after 8 hours, with a maximum of 3000 mg in 24 hours).

Postoperative pain intensity will be assessed by another investigator (Investigator 2) at 0, 2, 6, 12, and 24 hours after surgery using the NPRS, both at rest and during coughing. Total opioid consumption, rescue analgesic use, incidence of postoperative complications, and length of hospital stay will also be recorded.

Twenty-four hours after surgery, Investigator 2 will administer the Quality of Recovery-15 (QoR-15) questionnaire to all patients. The responses will be used to calculate the QoR-15 index, summarizing overall patient satisfaction. Both patients and Investigator 2 will be blinded to the type of block administered, ensuring the study is conducted in a blinded manner.

Inclusion Criteria:

• Patients over 18 years of age with lung neoplasm who are candidates for pulmonary resection surgery via Uniportal-VATS
• Patients who have provided informed consent to participate in the study

Exclusion Criteria:

• Patients who refuse to participate in the study by not signing the informed consent;
• Patients with severe obesity (BMI > 35), history of OSAS with or without CPAP;
• Patients classified as ASA > 3, according to the system established by the American Society of Anesthesiologists;
• Patients unable to understand the use of the NPR Scale or the PCA device that will be used for postoperative analgesia;
• Patients with allergies to analgesic and/or anesthetic drugs;
• Patients undergoing anticoagulant therapy;
• Patients with a history of chronic pain;
• Patients with an infection at the site where SPSIPB or ICNB will be performed;
• Patients with a history of thoracic surgery and/or thoracic trauma with rib fractures on the side of surgery;
• Patients with chest wall deformities and/or neuromuscular diseases that interfere with normal ventilatory function.

Additionally, patients whose surgical procedure is intraoperatively converted to an open pulmonary resection will be excluded post hoc from the study.