Effects of Erector Spinae Plane Block and Intrathecal Morphine Administration on Intraoperative Sevoflurane Consumption

The amount of volatile anesthetic agents used for anesthesia maintenance can be significantly reduced with potent and long-acting analgesic interventions administered during the preoperative period. Such interventions enable the maintenance of anesthesia with more optimal levels of agents during surgery, providing significant advantages in terms of both patient safety and cost.

Studies have recommended multimodal analgesia approaches involving the Erector Spinae Plane (ESP) block and intrathecal morphine (ITM) injection for various surgical procedures. These two methods, through different mechanisms of action, not only reduce intraoperative anesthetic agent consumption but also play a critical role in postoperative pain management. Although studies have investigated the effects of ESP block and ITM injection on intraoperative volatile anesthetic consumption, there is limited research directly comparing their impacts on volatile anesthetic consumption and postoperative analgesic requirements.

In our study, we aimed to compare the intraoperative sevoflurane consumption and postoperative analgesic needs of patients who underwent lumbar disc herniation surgery and received either ESP block or ITM in the preoperative period with a control group.

Inclusion criteria

• Patients aged over 18 years
• Patients receiving general anesthesia
• Patients with an ASA score of I-II
• Patients undergoing elective surgery for single-level lumbar disc herniation
• Patients who provided informed consent after being informed

Exclusion criteria

Patients who did not provide informed consent after being informed

• Patients over 65 years of age
• Patients with an ASA score of III or higher
• Patients with recurrent lumbar disc herniation (LDH)
• Patients undergoing surgery for multi-level LDH
• Patients with a body mass index (BMI) of 30 or higher
• Patients with allergies to morphine or bupivacaine
• Patients with major cardiac, respiratory, hepatic, renal, neurological, or psychiatric diseases
• Patients with a history of alcohol or substance abuse
• Patients with a local infection at the injection site
• Patients with bleeding diathesis
• Patients with a history of anticoagulant medication use
• Patients with contraindications to spinal or regional anesthesia