Low-flow Versus Minimal-flow Sevoflurane Anesthesia During Robot-assisted Laparoscopic Radical Prostatectomy

NCT07475533 | Not Yet Recruiting

• 1 other identifier: TABED1-26-2261
• Study Type: interventional
• Target: 70
• Locations: 0 countries
• Sites: N/A

Brief Summary

Study Synopsis This protocol is formatted for ClinicalTrials.gov-style registration and manuscript-facing documentation. It is based on the uploaded Turkish ethics protocol and keeps the original core design: comparison of low-flow and minimal-flow sevoflurane anesthesia in robot-assisted laparoscopic radical prostatectomy. Background and Rationale Robot-assisted laparoscopic radical prostatectomy (RALRP) is increasingly preferred for localized prostate cancer because of lower blood loss, reduced transfusion requirements, shorter hospitalization, and lower complication rates compared with open surgery. However, RALRP requires carbon dioxide pneumoperitoneum and steep Trendelenburg positioning, both of which may adversely affect respiratory mechanics, gas exchange, and hemodynamic stability. Low-flow and minimal-flow anesthesia may improve humidification and warming of inspired gases, reduce inhalational agent consumption, decrease environmental waste, and potentially lower overall cost. Despite these theoretical and practical advantages, evidence remains limited regarding the physiologic safety and performance of minimal-flow sevoflurane anesthesia during long robotic pelvic surgery performed under pneumoperitoneum and steep Trendelenburg positioning. Accordingly, this randomized prospective trial will compare low-flow (1 L/min) and minimal-flow (0.5 L/min) sevoflurane anesthesia during RALRP with respect to respiratory parameters, arterial blood gas values, intraoperative oxygenation variables, anesthetic consumption, and selected postoperative biochemical markers.

Conditions

Prostate Cancer; Anesthesia; Respiratory Mechanics

Outcome Measures

Primary Outcomes (1)

• Arterial partial pressure of carbon dioxide (PaCO₂)

  Comparison of arterial PaCO₂ values between the minimal-flow anesthesia group (0.5 L/min) and the low-flow anesthesia group (1 L/min) measured during robot-assisted laparoscopic radical prostatectomy. Arterial blood gas analysis will be performed at predefined intraoperative time points (T0: post-intubation, T1: before pneumoperitoneum, T2: after pneumoperitoneum and positioning, hourly during pneumoperitoneum, at the end of pneumoperitoneum, and before extubation).

  intraoperative period, from post-intubation to before extubation on the day of surgery

Secondary Outcomes (3)

• End-tidal carbon dioxide (EtCO₂)

  intraoperatively

• Oxygenation parameters

  Intraoperative period (T0-Text).

• Inhalational anesthetic consumption

  Postextubation

Study Arms (2)

Low-flow sevoflurane arm

EXPERIMENTAL

After tracheal intubation, fresh gas flow will be set at 1 L/min until MAC 1 is achieved. Thereafter, flow will be reduced to 0.5 L/min for maintenance.

Other: Common Anesthetic Management

Minimal-flow sevoflurane anesthesia

EXPERIMENTAL

Fresh gas flow 1 L/min after intubation until MAC 1 is achieved, then reduced to 0.5 L/min for maintenance anesthesia.

Other: Common Anesthetic Management

Interventions

Common Anesthetic Management OTHER

Standard intraoperative monitoring including BIS, pulse oximetry, temperature, and anesthesia workstation-derived respiratory variables. * Arterial blood gas sampling after intubation, before pneumoperitoneum, after pneumoperitoneum/positioning, hourly during pneumoperitoneum, at the end of pneumoperitoneum in supine position, and before extubation. * Routine safety limits on the anesthesia machine: end-tidal carbon dioxide upper alarm 45 mmHg, inspired oxygen lower alarm 35%, inspired carbon dioxide upper alarm 3 mmHg. * Routine device self-test each morning and between patients. * Minimal dead space strategy with avoidance of unnecessary circuit extension. * Close monitoring of soda lime; replacement if inspired carbon dioxide reaches 3 mmHg even without obvious color change. * If clinically necessary because of blood gas deterioration, BIS changes, or any safety concern, fresh gas flow may be increased and the participant may be withdrawn from the protocol intervention.

Low-flow sevoflurane arm; Minimal-flow sevoflurane anesthesia

Eligibility Criteria

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

You may qualify if:

• Male patients aged 18 years or older.
• ASA physical status I-II.
• Scheduled for elective robot-assisted laparoscopic radical prostatectomy.

You may not qualify if:

• ASA physical status III-V.
• Severe cardiac, respiratory, hepatic, or renal disease.
• Mental status disorder or significant hearing impairment that prevents consent or communication.
• Known anxiety, depression, or other psychiatric disorder judged to interfere with study participation.
• Withdrawal of consent or investigator decision for safety reasons.

Sponsors & Collaborators

• Ankara City Hospital Bilkent: lead

MeSH Terms

Conditions

Prostatic Neoplasms

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assos. Prof

Study Record Dates

• First Submitted: March 8, 2026
• First Posted: March 16, 2026
• Study Start: March 20, 2026
• Primary Completion: April 20, 2026
• Study Completion (Estimated): August 31, 2026
• Last Updated: April 15, 2026

Record last verified: 2026-04