Intraoperative HypotensionNCT07794852
Dural Sac Area-Guided Spinal Anesthesia Dosing for TURP
A study testing DSCSA-Guided Individualized Spinal Anesthesia Dosing, Bupivacaine and Fentanyl (FEN) in people with Intraoperative Hypotension and Spinal Aneshtesia, run by Istanbul University at 1 site in Turkey (Türkiye).
Trial summary
This randomized controlled study will evaluate whether individualizing the dose of spinal anesthesia according to the ultrasound-derived dural sac cross-sectional area (DSCSA) can improve hemodynamic stability in patients undergoing transurethral resection of the prostate (TURP). Read more about this study
- Who is it for?
- Ages 40 years and older, men only
- Conditions the study is for
- Intraoperative Hypotension, Spinal Aneshtesia, TURP(Transurethral Resection of Prostate)
- What is being tested?
- DSCSA-Guided Individualized Spinal Anesthesia Dosing, Bupivacaine and Fentanyl (FEN)
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 27 Aug 2026to 10 Dec 2026
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 40 years and older
- Men only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Male participants aged 40 years or older
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled to undergo transurethral resection of the prostate (TURP) for prostate cancer
Who cannot join
- Refusal of spinal anesthesia
- Local infection or wound at the planned puncture site
- Current anticoagulant therapy
- Neurological disease, including multiple sclerosis, myelopathy, or peripheral neuropathy
- Known allergy to any of the study medications
- Inability to maintain the required position during ultrasound measurement or spinal puncture
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site
Istanbul University-Cerrahpasa, Cerrahpasa Faculty of Medicine
Istanbul, 34360
About this study
Official title: Clinical Effects of Individualized Spinal Anesthesia Dosing Based on Ultrasound-Measured Dural Sac Cross-Sectional Area in Patients Undergoing Transurethral Resection of the Prostate: A Prospective, Randomized Controlled Trial
This randomized controlled study will evaluate whether individualizing the dose of spinal anesthesia according to the ultrasound-derived dural sac cross-sectional area (DSCSA) can improve hemodynamic stability in patients undergoing transurethral resection of the prostate (TURP).
Participants aged 40 years or older will be randomly assigned to one of two groups. In the individualized-dose group, the anteroposterior diameter of the dural sac will be measured by ultrasound at the L3-L4 level, and DSCSA will be calculated from this measurement. The dose of intrathecal bupivacaine will then be individualized according to the calculated DSCSA. In the control group, participants will receive a fixed dose of intrathecal bupivacaine. Both groups will also receive intrathecal fentanyl.
Read more
The main outcome is the incidence of intraoperative hypotension. The study will also evaluate the number of hypotensive episodes, minimum mean arterial pressure, vasopressor and atropine requirements, sensory and motor block characteristics, respiratory monitoring parameters, cerebral oxygenation, and adverse events.
The study aims to determine whether a DSCSA-guided dosing strategy can reduce excessive spinal block and improve hemodynamic stability while maintaining effective spinal anesthesia.
Read the detailed description
This prospective, randomized controlled study compares two routinely used approaches to determining the intrathecal bupivacaine dose for spinal anesthesia in patients undergoing transurethral resection of the prostate (TURP). No new drug, new indication, or experimental treatment will be introduced. Both dosing approaches are currently used in routine clinical practice; the study will prospectively and randomly compare their clinical effects.
Participants will be randomly assigned to either a dural sac cross-sectional area (DSCSA)-guided individualized dosing group or a fixed-dose control group.
Before spinal anesthesia, the anteroposterior diameter of the dural sac will be measured by ultrasound at the L3-L4 intervertebral level. DSCSA will be calculated using the formula A = π × (D/2)².
In the individualized-dose group, a DSCSA of 150 mm² will be used as the reference value corresponding to 10 mg of intrathecal bupivacaine. The bupivacaine dose will be adjusted proportionally according to the participant's calculated DSCSA and limited to a minimum of 6 mg and a maximum of 12.5 mg. Fentanyl 25 micrograms will be added intrathecally.
In the fixed-dose group, participants will receive 10 mg (2 mL of 0.5%) intrathecal bupivacaine together with fentanyl 25 micrograms.
Spinal anesthesia will be performed at the L3-L4 intervertebral space using a 27-gauge Quincke needle. Standard intraoperative monitoring will be performed according to the study protocol. Sensory and motor block characteristics and hemodynamic variables will be recorded prospectively for comparison between the two dosing strategies.
- Being tested
- DSCSA-Guided Individualized Spinal Anesthesia Dosing, Bupivacaine, Fentanyl (FEN)
- Keywords
- Dural sac cross-sectional area, Spinal anesthesia, Individualized spinal anesthesia, Ultrasound, Intraoperative hypotension, Hemodynamic stability, Transurethral resection of the prostate
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
DSCSA-Guided Individualized Spinal Anesthesia DosingProcedure or surgery
The dural sac cross-sectional area (DSCSA) is calculated from the ultrasound-measured anteroposterior dural sac diameter at the L3-L4 level. The intrathecal bupivacaine dose is individualized according to DSCSA.
BupivacaineDrug
Hyperbaric bupivacaine is administered intrathecally in both study groups. In the DSCSA-guided group, the dose is individualized according to DSCSA, using 150 mm² as the reference corresponding to 10 mg, with a permitted dose range of 6 to 12.5 mg. In the fixed-dose group, 10 mg (2 mL of 0.5% bupivacaine) is administered.
Fentanyl (FEN)Drug
Fentanyl 25 micrograms is administered intrathecally together with bupivacaine in both study groups.
| Study group | Role | What they receive |
|---|---|---|
| DSCSA-Guided Individualized Dose | Experimental | The dural sac cross-sectional area (DSCSA) will be estimated from the ultrasound-measured anteroposterior dural sac diameter at the L3-L4 level. The intrathecal bupivacaine dose will be individualized according to the DSCSA, using 150 mm² as the reference area corresponding to 10 mg bupivacaine. The calculated bupivacaine dose will be limited to 6-12.5 mg. Fentanyl 25 micrograms will also be administered intrathecally. Receives: Procedure: DSCSA-Guided Individualized Spinal Anesthesia Dosing; Drug: Bupivacaine; Drug: Fentanyl (FEN) |
| Fixed Dose | Active comparator | Participants will receive a fixed intrathecal dose of 10 mg (2 mL of 0.5%) bupivacaine together with fentanyl 25 micrograms. Receives: Drug: Bupivacaine; Drug: Fentanyl (FEN) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Intraoperative Hypotension
Intraoperative hypotension is defined as a decrease in mean arterial pressure (MAP) of ≥20% from baseline or an MAP <65 mmHg. Participants meeting either criterion at least once during surgery will be classified as having intraoperative hypotension. The outcome will be reported as the percentage of participants with intraoperative hypotension.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Secondary outcomes (13)
Number of Intraoperative Hypotension Episodes
Number of intraoperative hypotension episodes recorded for each participant. Hypotension is defined as a decrease in mean arterial pressure (MAP) of ≥20% from baseline or an MAP <65 mmHg.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Minimum Intraoperative Mean Arterial Pressure
Lowest mean arterial pressure (MAP), measured in mmHg, recorded during the intraoperative period.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Percentage of Participants With a ≥30% Decrease in Mean Arterial Pressure
Percentage of participants experiencing at least one decrease in mean arterial pressure (MAP) of ≥30% from baseline during surgery.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Percentage of Participants Requiring Ephedrine
Percentage of participants receiving at least one intravenous dose of ephedrine for treatment of intraoperative hypotension.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Total Ephedrine Dose
Total intravenous ephedrine dose, measured in milligrams (mg), administered to each participant during surgery.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Percentage of Participants Requiring Atropine
Percentage of participants receiving intravenous atropine for treatment of intraoperative bradycardia.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Total Atropine Dose
Total intravenous atropine dose, measured in milligrams (mg), administered to each participant during surgery.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Maximum Sensory Block Level
Highest cephalad sensory block level achieved after spinal anesthesia, assessed by the pin-prick test and recorded as the corresponding dermatomal level.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Time to Achieve T10 Sensory Block
Time, measured in minutes, from completion of intrathecal injection to achievement of a T10 sensory block, assessed using the pin-prick test.
Measured: Up to 30 minutes after spinal anesthesia
Time to Two-Dermatome Sensory Regression
Time, measured in minutes, from the maximum sensory block level to regression of the sensory block by two dermatomes, assessed using the pin-prick test.
Measured: From maximum sensory block until two-dermatome regression, assessed up to 3 hours after spinal anesthesia
Time to Recovery to Modified Bromage Score 0
Time, measured in minutes, from completion of intrathecal injection until recovery to a Modified Bromage score of 0, indicating complete recovery of lower-extremity motor function.
Measured: From completion of spinal anesthesia until recovery to Modified Bromage score 0, assessed up to 3 hours after spinal anesthesia
Number of Integrated Pulmonary Index ≤4 Episodes
Number of episodes in which the Integrated Pulmonary Index (IPI) is ≤4. The IPI is a composite score ranging from 1 to 10 based on end-tidal carbon dioxide, respiratory rate, oxygen saturation, and pulse rate; lower scores indicate greater respiratory compromise.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Incidence of Adverse Events
Percentage of participants experiencing at least one adverse event recorded during the intraoperative study period.
Measured: During surgery (from completion of spinal anesthesia until the end of surgery)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted31 Aug 2026
- Study start27 Aug 2026
- Primary completion24 Nov 2026 (estimated)
- Study completion10 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Intraoperative HypotensionStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Participants are randomly assigned in parallel to either dural sac cross-sectional area-guided individualized spinal anesthesia dosing or fixed-dose spinal anesthesia.
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Istanbul University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Ezgi Budak Ozyalcın, Istanbul University - Cerrahpasa
- Investigators
- Ezgi Budak Özyalçın, MD, Principal investigator, Istanbul University - Cerrahpasa
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07794852
- Sponsor's protocol ID
- E-24687260-604.01-1701514
- Status last verified
- Aug 2026
- First submitted
- 23 Aug 2026
- Last updated
- 1 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No