The Effect of Neostigmine and Sugammadex on the Optic Nerve Sheath Diameter

Comparison of the Effects of Neostigmine and Sugammadex on the Optic Nerve Sheath Diameter During the Postoperative Extubation Period

This study will compare how two drugs, sugammadex and neostigmine-used to reverse muscle relaxation after surgery-affect the size of the optic nerve sheath (the nerve behind the eye) as patients wake up and have their breathing tubes removed. It will also examine the relationship between changes in blood pressure and heart rate during this time and these measurements. This study will be conducted on 86 healthy patients aged 18-65 who will undergo planned surgery at the Çukurova University Faculty of Medicine, Department of Anesthesiology and Reanimation. Patients will be randomly divided into two groups: the sugammadex group and the neostigmine group. All patients will receive standard general anesthesia and rocuronium to relax their muscles. At the end of the surgery, to reverse this effect, patients will be given either sugammadex or a mix of neostigmine and atropine. Group S will receive 2 mg sugammadex per kg, while Group N will receive 0.05 mg neostigmine and 0.02 mg atropine per kg. The width of the optic nerve sheath will be measured by ultrasound 5 minutes after the breathing tube is inserted, 5 minutes before the tube is removed, and 5 minutes after it is removed. Additionally, blood pressure, heart rate, and any complications during the surgery will be tracked and compared between the groups.

Study Overview

• Status: Recruiting
• Conditions: Neuromuscular Blockade Reversal Agent
• Intervention / Treatment: Drug: Sugammadex 2 mg/kg; Drug: Neostigmine + Atropine

Detailed Description

The study will be conducted prospectively, randomly, and double-blind on a total of 86 patients aged 18-65 years, classified as ASA 1-2, undergoing elective surgery at the Department of Anesthesiology and Reanimation, Faculty of Medicine, Çukurova University. Written and verbal informed consent will be obtained from all participants prior to the study.

The demographic data, such as age, gender, body weight, and height, as well as ASA score and information on comorbidities, will be recorded for the patients included in the study in the preoperative anesthesia care unit. All patients who will be taken to the operating room without premedication will undergo routine monitoring, including electrocardiography, noninvasive blood pressure monitoring, and peripheral oxygen saturation. During induction of anesthesia, propofol IV 2 mg/kg, rocuronium IV 0.6 mg/kg, and fentanyl IV 1 mcg/kg will be used. After observing adequate muscle relaxation with a TOF (Train-of-Four) monitor, tracheal intubation will be performed. All patients will receive mechanical ventilation after intubation. During anesthesia, a gas mixture of 2% sevoflurane, 60% nitrous oxide, and 40% oxygen will be administered at a flow rate of 2 L/min. To maintain muscle relaxation throughout the surgery, when a TOF of 2 is observed, 0.2 mg/kg of rocuronium IV will be administered. Tramadol 2 mg/kg IV will be given 45 minutes before the end of surgery for postoperative pain management. Ondansetron 8 mg IV will be planned as antiemetic treatment. At the end of the surgery, the maintenance gases will be discontinued, and according to the randomization, the anesthesiologist responsible for anesthesia administration will either administer 2 mg/kg Sugammadex IV or 0.05 mg/kg Neostigmine IV plus 0.02 mg/kg atropine sulfate IV. Patients who show a TOF value of 90% and clinically adequate respiration will be extubated.

In addition to the anesthesiologist responsible for administering anesthesia, one blinded evaluator for each group will perform three ultrasound measurements on both eyes to determine the Optic nerve sheath diameter at 5 minutes after endotracheal intubation, 5 minutes before extubation, and 5 minutes after extubation. The measurements will be recorded while the patient is in a supine position, with ultrasound gel applied to the eyelid, using a linear probe without applying pressure to the eyeball.

The diameter of the optic nerve sheath will be systematically measured at a point 3.0 mm posterior to the optic disc to ensure consistent anatomical evaluation.

• Study Type: Interventional
• Enrollment (Estimated): 86
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Ersel Gulec, MD; Phone Number: 3289 +903223386060; Email: gulecersel@yahoo.com

Study Locations

• Turkey (Türkiye)
  • Adana, Turkey (Türkiye)
    • Recruiting
    • Cukurova University Faculty of Medicine
    • Principal Investigator: Ersel Gulec, MD
    • Sub-Investigator: Mediha Turktan, MD
    • Sub-Investigator: Zehra Hatipoglu, MD
    • Sub-Investigator: Dilek Ozcengiz, MD
    • Contact: Ersel Gulec, MD; Phone Number: 3289 +903223386060; Email: gulecersel@yahoo.com
    • Sub-Investigator: Kubra Gunsur, MD
    • Sub-Investigator: Demet Lafli Tunay, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• With an ASA physical status of 1-2
• Patients scheduled for elective surgery
• Patients willing to participate in the study

Exclusion Criteria:

• Patients with heart, liver, kidney, or respiratory failure
• Brain tumors, hemorrhages, or aneurysms
• Patients who have undergone eye, cardiovascular, or neurosurgery
• Eye or neurological diseases or increased intracranial pressure
• Laparoscopic surgeries
• Cases not in the supine position
• Allergy to the medications used
• Patients who did not provide informed consent to participate in the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Group S; Sugammadex, intravenous, 2 mg/kg, single bolus dose.	Drug: Sugammadex 2 mg/kg; Intravenous bolus injection
Active Comparator: Group N; Neostigmine, intravenous, 0.05 mg/kg, single bolus dose. Atropine sulfate, intravenous, 0.02 mg/kg, single bolus dose.	Drug: Neostigmine + Atropine; Intravenous bolus injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in average optic nerve sheath diameter from intubation to the 5th minute after extubation	Three measurements will be taken for each eye using ultrasound to determine the diameter of the optic nerve sheath at 5 minutes after endotracheal intubation, 5 minutes before extubation, and 5 minutes after extubation; the average values for each eye will be recorded. Subsequently, the averages of the measurements obtained for both eyes will be calculated. Changes in these averages over time will be compared between groups.	From the time of endotracheal intubation until 5 minutes after extubation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Blood Pressure	Blood pressure will be measured and recorded 5 minutes after endotracheal intubation, 5 minutes before extubation, and 5 minutes after extubation	From the time of endotracheal intubation until 5 minutes after extubation
Postoperative nausea and vomiting	The number of patients who experienced nausea and vomiting upon waking from anesthesia and during their stay in the postoperative care unit.	The one-hour period from endotracheal tube removal to patient discharge from the postoperative care unit.
Blood pressure	Noninvasive measurement of blood pressure	The one-hour period from endotracheal tube removal to patient discharge from the postoperative care unit.

Collaborators and Investigators

• Sponsor: Cukurova University
• Investigators: Principal Investigator: Ersel Gulec, MD, Çukurova University

Publications and helpful links

General Publications

• Rajajee V, Vanaman M, Fletcher JJ, Jacobs TL. Optic nerve ultrasound for the detection of raised intracranial pressure. Neurocrit Care. 2011 Dec;15(3):506-15. doi: 10.1007/s12028-011-9606-8.
• Maissan IM, Dirven PJ, Haitsma IK, Hoeks SE, Gommers D, Stolker RJ. Ultrasonographic measured optic nerve sheath diameter as an accurate and quick monitor for changes in intracranial pressure. J Neurosurg. 2015 Sep;123(3):743-7. doi: 10.3171/2014.10.JNS141197. Epub 2015 May 8.
• P S L, Miskan MM, Y Z C, Zaki RA. Staggering the dose of sugammadex lowers risks for severe emergence cough: a randomized control trial. BMC Anesthesiol. 2017 Oct 11;17(1):137. doi: 10.1186/s12871-017-0430-3.

Study record dates

Study Major Dates

• Study Start (Actual): June 4, 2026
• Primary Completion (Estimated): July 10, 2026
• Study Completion (Estimated): July 10, 2026

Study Registration Dates

• First Submitted: June 8, 2026
• First Submitted That Met QC Criteria: June 19, 2026
• First Posted (Actual): June 24, 2026

Study Record Updates

• Last Update Posted (Actual): June 24, 2026
• Last Update Submitted That Met QC Criteria: June 19, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Optic nerve sheath diameter; Neuromuscular Blockade reversal agent
• Additional Relevant MeSH Terms: Organic Chemicals; Heterocyclic Compounds; Carbohydrates; Alkaloids; Polycyclic Compounds; Amines; Aza Compounds; Polysaccharides; Macrocyclic Compounds; Phenylammonium Compounds; Quaternary Ammonium Compounds; Onium Compounds; gamma-Cyclodextrins; Cyclodextrins; Dextrins; Starch; Glucans; Heterocyclic Compounds, Bridged-Ring; Atropine Derivatives; Tropanes; Azabicyclo Compounds; Belladonna Alkaloids; Solanaceous Alkaloids; Bridged Bicyclo Compounds, Heterocyclic; Atropine; Neostigmine; Sugammadex
• Other Study ID Numbers: 25-AKD-309

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All collected IPD may be shared with relevant parties upon request, with the principal investigator's approval, provided that no personally identifiable information or hospital records are disclosed.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No