Effect of Spinal Needle Type on Optic Nerve Sheath Diameter

Summary

The optic nerve sheath is a continuation of the dura mater, extending along the subarachnoid space surrounding the optic nerve. Consequently, changes in intracranial pressure cause an augmentation or contraction in the diameter of the optic nerve sheath, which is coreleted with intracranial pressure. Participants undergoing lower extremity operations (ankle, distal tibia and fibula surgeries) using a tourniquet under spinal anesthesia will be investigated. Spinal anesthesia will be performed with a 25 G Whitacre, 25 G Quincke, or 27 G Quincke needle, depending on the study group. Optic nerve sheath diameter (ONSD) measurements will be performed before spinal anesthesia; and 5 minutes, 15 minutes,,24 hours after spinal block, respectively.The 4th measurement will be performed after tourniquet is opened. Measurements will be done with 15 MHz linear ultrasound (US) probe in B mode, 3 mm behind the posterior globe in the transverse plane from both eyes, on upper eyelid. Values will be recorded numerically. The impact of spinal anesthesia administered using various needle designs (Quincke and Whitacre) and sizes (25G-27G) on intracranial pressure will be investigated.

Conditions

• Spinal Anesthesia
• Intracranial Pressure Change
• Optic Nerve Sheath Diameter
• Orthopedic Surgery
• Cerebrospinal Fluid Leak

Interventions

PROCEDURE

25 PP

Spinal anesthesia will be performed in sitting position, with 25 G pencil point needle (Whitacre -Egemen®) midline through the L4-5 or L5-S1 interspace, parallel to the dural fibers. Upon clear cerebrospinal fluid (CSF) detection, the needle apertures will be turned towards the cephalad direction, and 3 ml (15 mg) of 0.5% hyperbaric bupivacaine (Marcaine Heavy ®) will be injected into the intrathecal space.

PROCEDURE

25 Q

Spinal anesthesia will be performed in sitting position, with 25 G sharp edge needle (Quincke -Egemen®) midline through the L4-5 or L5-S1 interspace, parallel to the dural fibers. Upon clear cerebrospinal fluid (CSF) detection, the needle apertures will be turned towards the cephalad direction, and 3 ml (15 mg) of 0.5% hyperbaric bupivacaine (Marcaine Heavy ®) will be injected into the intrathecal space.

PROCEDURE

27 Q

Spinal anesthesia will be performed in sitting position, with 27 G sharp edge needle (Quincke -Egemen®) midline through the L4-5 or L5-S1 interspace, parallel to the dural fibers. Upon clear cerebrospinal fluid (CSF) detection, the needle apertures will be turned towards the cephalad direction, and 3 ml (15 mg) of 0.5% hyperbaric bupivacaine (Marcaine Heavy ®) will be injected into the intrathecal space.

OTHER

Optic Nerve Sheath Measurement

Sonographic measurement of ONSD (EsaoteMyLabFive, Cenova, Italy) for all patients will be performed by a single experienced anesthesiologist. After a thin gel layer apply to the upper eyelid, the patient in the supine position and with the eyes closed, using a 6-13 MHz linear probe, optic sheath nerve measurement will be done 3 mm behind the optic globe, with a total of three measurements of which the final value will be recorded.The measurement will be repeated five times using US guidance at the following time points: T0 (pre-anesthesia), T1 (5 minutes after spinal block), T2 (15 minutes after spinal block, T3 (tourniquet opening), and T4 (24 hours after spinal block ) respectively.

Sponsors & Collaborators

• Bagcilar Training and Research Hospital

  lead OTHER_GOV

Principal Investigators

• sezen kumas solak, MD · Bagcılar Training Research Hospital

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

40 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-08-15

Primary Completion

2024-12-25

Completion

2024-12-30

Countries

• Turkey (Türkiye)

Study Locations