This study is designed to compare three different methods of pain control after laparoscopic gallbladder surgery (laparoscopic cholecystectomy). Although this surgery is minimally invasive, participants often experience different types of pain after the operation, such as pain at the incision site, pain inside the abdomen, and shoulder pain caused by the gas used during surgery.

The investigators will compare three commonly used pain relief techniques:

Local infiltration - injecting a numbing medicine (bupivacaine) into the gallbladder bed and at the sites where the surgical instruments are placed.

Erector spinae plane (ESP) block - an ultrasound-guided nerve block performed in the back to reduce both abdominal and incisional pain.

Intrathecal morphine - a very small dose of morphine given into the spinal fluid before surgery to provide long-lasting pain relief.

The goal is to determine which method provides the best pain control, reduces the need for opioid medications, and improves recovery after surgery.

Laparoscopic cholecystectomy is the standard surgical treatment for gallbladder diseases. Despite being a minimally invasive procedure, postoperative pain is a frequent problem and can negatively affect early mobilization, oral intake, and overall recovery. The pain experienced after this surgery is multifactorial, including somatic pain at trocar sites, visceral pain at the gallbladder bed, and shoulder pain caused by carbon dioxide insufflation. Effective pain management is therefore essential to improve patient comfort, reduce opioid consumption, and shorten hospital stay.

Several methods are available for postoperative analgesia. Local infiltration of the gallbladder bed and trocar sites with bupivacaine provides targeted pain relief at areas of surgical trauma. Erector spinae plane (ESP) block, a recently described ultrasound-guided regional anesthesia technique, offers both somatic and visceral analgesia with a favorable safety profile. Low-dose intrathecal morphine has also been shown to provide strong and prolonged analgesia in abdominal surgery, though its use may be limited by side effects such as nausea, vomiting, and itching.

This single-center, prospective, randomized controlled trial will compare the analgesic efficacy of three techniques:

Group INF (Infiltration): Bupivacaine infiltration at the gallbladder bed and trocar sites.

Group ESP: Bilateral ultrasound-guided ESP block at the T7 level.

Group ITM: Intrathecal morphine administration before induction of anesthesia.

The primary outcome is total opioid consumption within the first 24 hours after surgery.

Secondary outcomes include postoperative pain scores at multiple time points using the Visual Analog Scale (VAS), as well as the incidence of side effects such as nausea, vomiting, pruritus, and respiratory depression.

The results of this study are expected to provide evidence to guide multimodal analgesia strategies in laparoscopic cholecystectomy and to optimize patient recovery and satisfaction.

Inclusion Criteria:

• Adults aged 18-65 years
• Scheduled for elective laparoscopic cholecystectomy
• American Society of Anesthesiologists (ASA) physical status I-III
• Able to provide written informed consent

Exclusion Criteria:

• Body mass index (BMI) > 35 kg/m²
• History of coagulopathy or bleeding disorders
• Known allergy or hypersensitivity to opioids or local anesthetics
• Chronic pain or regular analgesic use
• History of neurological or psychiatric disease
• Pregnancy
• Refusal to participate in the study

Individual participant data (IPD) will not be shared because the study involves sensitive patient health information, and data confidentiality will be strictly maintained according to institutional ethical guidelines.

Participants and postoperative outcome assessors will be blinded to group allocation. The anesthesiologist performing the intervention cannot be blinded due to the nature of the procedures, but will not be involved in postoperative data collection or outcome assessment. Thus, the trial will be conducted with patient- and assessor-blinding to minimize bias.