The COMPARISON OF INTRATHECAL NEOSTIGMINE VERSUS FENTANYL AS ADJUVANTS TO SPINAL ANESTHESIA IN ELECTIVE SURGERIES

Shaimaa Hamid Hasan; HEVY HUSSEN RAMO

Shaimaa Hamid Hasan Corresponding Author: Anesthesiologist, Department of Anesthesia Sciences, College of Health Sciences, University of Duhok, Kurdistan Region, Iraq.
HEVY HUSSEN RAMO Dept. of Anesthesia Sciences, College of Health Sciences, University of Duhok, Kurdistan Region, Iraq. Email: [email protected]

Keywords: Spinal anesthesia adjuvants, Intrathecal neostigmine, intrathecal fentanyl, hemodynamic stability

Abstract

https://doi.org/10.31386/dmj.2025.19.2.11

Abstract

Background: Spinal anesthesia is a widely employed method in elective surgeries due to its efficacy, and adjuvants such as fentanyl are commonly added to enhance analgesia. Although neostigmine (a cholinesterase inhibitor) has analgesic benefits when used as an adjuvant, less commonly used due to its perceived side effects. This study aimed to compare the efficacy and safety of intrathecal neostigmine with intrathecal fentanyl as adjuvants in patients undergoing elective lower abdominal surgery.

Method: A total of 184 were randomly assigned to receive either neostigmine (15µg) or fentanyl (15µg) intrathecally with 15mg of heavy bupivacaine. Patients’ hemodynamic stability, vital signs, dermatomal level of the sensory block, motor block intensity, and duration of postoperative analgesia, mobility time, and post-spinal anesthesia complications were documented perioperatively.

Result: Our findings indicated no significant difference in hemodynamic stability or complications (including nausea and vomiting) between the fentanyl group and the neostigmine group. However, neostigmine significantly prolonged the duration of postoperative analgesia with early mobility (p-value < 0.0001 and 0.0002, respectively) and delayed the onset of spinal anesthesia (p-value < 0.0001), which may limit its use.

Conclusion: This study found that intrathecal neostigmine at 15 µg is a valid alternative to intrathecal fentanyl, since it offers a longer duration of postoperative analgesia and earlier mobilization with insignificant difference in terms of intra- and postoperative complications as compared to intrathecal fentanyl.

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