HFNO Flow Rates and Cerebral Oxygenation During Deep Sedation for Cystoscopy

NCT07630038 | Not Yet Recruiting

• 1 other identifier: 47669
• Study Type: interventional
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

For Patients and Families This study aims to investigate how high-flow oxygen therapy affects oxygen levels, especially brain oxygenation, during cystoscopy procedures performed under sedation. The goal is to improve patient safety and comfort by ensuring better oxygen delivery during the procedure. Different oxygen flow rates will be compared, while patients' breathing, oxygen levels, and vital signs are continuously monitored throughout the procedure. All methods used in the study are consistent with routine anesthesia practices, and patient safety remains the highest priority. For Healthcare Professionals This prospective randomized controlled study evaluates the effects of different high-flow nasal oxygen (HFNO) flow rates on cerebral oxygenation, peripheral oxygenation, and ventilation parameters in patients undergoing cystoscopy under procedural sedation. The primary aim is to determine the contribution of HFNO to sedation safety and to provide clinical evidence regarding the optimal flow rate. In addition, hypoxemia incidence, airway intervention requirements, hemodynamic variables, and sedation depth are being analyzed.

Conditions

Deep Sedation; High Flow Nasal Canula; Cerebral Oxygenation; PSI

Keywords

High Flow Nasal Canula; Deep Sedation; rSO2; PSI

Outcome Measures

Primary Outcomes (1)

• Change in Regional Cerebral Oxygen Saturation (rSO₂)

  Unit: %. Regional cerebral oxygen saturation values measured by near-infrared spectroscopy (NIRS) during procedural sedation will be compared among the three HFNO flow rate groups to evaluate the effect of different HFNO flow rates on cerebral oxygenation.

  From baseline measurement before sedation until the end of the cystoscopy procedure (intraoperative period). Cerebral oxygen saturation (rSO₂) values are recorded continuously during procedural sedation.

Secondary Outcomes (10)

• Peripheral Oxygen Saturation (SpO₂)

  From baseline measurement before sedation until the end of the cystoscopy procedure (intraoperative period). Cerebral oxygen saturation (rSO₂) values are recorded continuously during procedural sedation.

• Partial arterial carbon dioxide pressure (PaCO₂)

  At baseline before the initiation of sedation and at the end of the cystoscopy procedure. Arterial blood gas analysis (PaCO₂) and end-tidal carbon dioxide (EtCO₂) measurements will be recorded at both time points.

• End-tidal carbon dioxide (EtCO₂)

  At baseline before the initiation of sedation and at the end of the cystoscopy procedure. End-tidal carbon dioxide (EtCO₂) measurements will be recorded at both time points.

• Incidence of Hypoxemia

  From the initiation of procedural sedation until the end of the cystoscopy procedure. Hypoxemia episodes occurring during the intraoperative sedation period will be recorded continuously.

• Airway Intervention Requirement

  From the initiation of procedural sedation until the end of the cystoscopy procedure. Any airway intervention requirement occurring during the intraoperative period will be recorded.

Study Arms (3)

HF40

EXPERIMENTAL

Participants receive high-flow nasal oxygen (HFNO) therapy at a flow rate of 40 L/min during procedural sedation for cystoscopy.

Device: High-Flow Nasal Oxygen 40 L/min (HF40)

HF55

EXPERIMENTAL

Participants receive HFNO therapy at a flow rate of 55 L/min during procedural sedation for cystoscopy.

Device: High-Flow Nasal Oxygen 55 L/min (HF55)

HF70

EXPERIMENTAL

Participants receive HFNO therapy at a flow rate of 70 L/min during procedural sedation for cystoscopy.

Device: High-Flow Nasal Oxygen 70 L/min (HF70)

Interventions

High-Flow Nasal Oxygen 40 L/min (HF40) DEVICE

Participants receive high-flow nasal oxygen (HFNO) therapy delivered through the OptiFlow™ system at a flow rate of 40 L/min with 100% heated and humidified oxygen during procedural sedation for cystoscopy. Sedation is achieved using midazolam, remifentanil, and propofol.

HF40

High-Flow Nasal Oxygen 55 L/min (HF55) DEVICE

Participants receive HFNO therapy via the OptiFlow™ system at a flow rate of 55 L/min with 100% heated and humidified oxygen during procedural sedation for cystoscopy, together with the same standardized sedation protocol.

HF55

High-Flow Nasal Oxygen 70 L/min (HF70) DEVICE

Participants receive HFNO therapy via the OptiFlow™ system at a flow rate of 70 L/min with 100% heated and humidified oxygen during procedural sedation for cystoscopy, together with the same standardized sedation protocol.

HF70

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age ≥18 years
• Scheduled to undergo elective cystoscopy under procedural sedation in an operating room setting
• American Society of Anesthesiologists (ASA) physical status classification I-III
• Ability to provide written informed consent

You may not qualify if:

• Known neurological disorders
• History of ischemic or hemorrhagic stroke
• Peripheral artery disease
• Vasculitis
• Severe heart failure
• Uncontrolled hypertension
• Uncontrolled diabetes mellitus
• Advanced-stage chronic obstructive pulmonary disease
• Severe anemia (hemoglobin \<8 g/dL)
• Skin lesions that could interfere with near-infrared spectroscopy (NIRS) measurements
• History of head trauma
• History of cranial surgery
• Nasal deformity or nasal obstruction

Sponsors & Collaborators

• Firat University: lead

Study Sites (1)

Fırat University Faculty of Medicine Hospital

Elâzığ, Elaziğ, 23100, Turkey (Türkiye)

Location

Central Study Contacts

Ahmet Aksu, Assistant Professor

CONTACT

+905303493896; drahmetaksu@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
• Masking Details: Patients, surgeons, and outcome assessors were blinded to group allocation. Randomization codes were placed in sealed envelopes, and the assigned HFNO flow rate was known only to the anesthesiologist administering the intervention.
• Purpose: SCREENING
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: This is a prospective, randomized, parallel-group controlled study designed to evaluate the effects of different high-flow nasal oxygen (HFNO) flow rates during deep procedural sedation for cystoscopy. Participants are randomly assigned to one of three groups receiving HFNO at 40, 55, or 70 L/min. The study compares cerebral oxygenation, peripheral oxygenation, ventilation parameters, hypoxemia incidence, airway intervention requirements, and hemodynamic variables among the groups.

Study Record Dates

• First Submitted: May 22, 2026
• First Posted: June 5, 2026
• Study Start: June 1, 2026
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): October 1, 2026
• Last Updated: June 5, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)