Analgesia/Nociception Index (ANI)-Guided Desflurane Titration Reduces Anesthetic Consumption in Laparoscopic Cholecystectomy: A Prospective Randomized Controlled Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Wonkwang University Hospital
- Enrollment
- 125
- Locations
- 1
- Primary Endpoint
- Mean End-Tidal Desflurane Concentration
Study Overview
Brief Summary
General anesthesia requires precise titration of inhaled anesthetics like desflurane and opioids like remifentanil to balance sedation, analgesia, and hemodynamic stability. The Analgesia/Nociception Index (ANI), derived from heart rate variability (HRV), quantifies parasympathetic tone to assess nociception-antinociception balance on a 0-100 scale, with lower values indicating nociceptive stress. ANI analyzes high-frequency HRV components, reflecting parasympathetic inhibition during painful stimuli, making it a reliable indicator of intraoperative nociception. Studies validate the utility of ANI in detecting nociceptive events during laparoscopic surgery. ANI-guided opioid titration reduces opioid consumption and stabilizes hemodynamics, enhancing perioperative outcomes.
Detailed Description
Study Design This prospective, single-center, randomized controlled trial receives approval from the [Institutional Review Board Name] (Approval No. 2024-01-05-21-004). Written informed consent is obtained from all participants.
Participants Eligible patients are aged 19-65 years, American Society of Anesthesiologists (ASA) physical status I-II, and are scheduled for elective laparoscopic cholecystectomy under general anesthesia. Exclusion criteria include chronic pain, preoperative opioid use, cardiac arrhythmias, autonomic dysfunction, or contraindications to desflurane or remifentanil.
Randomization and Blinding Patients are randomized (1:1) to Analgesia/Nociception Index (ANI)-guided or standard care groups using a computer-generated sequence in blocks of four. Group allocation is concealed in opaque, sealed envelopes, which are opened before induction. Anesthesiologists remain unblinded due to ANI monitoring requirements, but patients and postoperative outcome assessors remain blinded to reduce bias.
Anesthesia Protocol Anesthesia is induced with propofol (2 mg/kg) and rocuronium (0.6 mg/kg). Maintenance includes desflurane and remifentanil (0.1 µg/kg/min continuous infusion). Ventilation maintains normocapnia (end-tidal Carbon dioxide: 35-40 mmHg). Bispectral index (BIS) is monitored to ensure hypnotic depth (target: 40-60).
Novel Metrics
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Triple (Participant, Care Provider, Outcomes Assessor)
Masking Description
Participants, care providers (excluding anesthesiologists), and outcome assessors were blinded to group allocation. Anesthesiologists administering anesthesia were unblinded due to the requirement for ANI monitoring and titration in the intervention group. Outcome assessors in the PACU were independent staff blinded to intraoperative management.
Eligibility Criteria
- Ages
- 19 Years to 65 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •aged 19-65 years, American Society of Anesthesiologists (ASA) physical status I-II, scheduled for elective laparoscopic cholecystectomy under general anesthesia.
Exclusion Criteria
- •chronic pain, preoperative opioid use, cardiac arrhythmias, autonomic dysfunction, or contraindications to desflurane or remifentanil.
Arms & Interventions
Control group
Desflurane was titrated based on vital signs (heart rate, blood pressure) and BIS 40-60, per institutional protocol.
Intervention: Analgesia/Nociception Index (ANI) (Device)
ANI-guided group
Desflurane started at 1 MAC (~6 Vol%), titrated in 0.1 MAC increments to maintain ANI 50-70 and BIS 40-60. ANI <50 prompted an increase; ANI >70 prompted a decrease
Intervention: Analgesia/Nociception Index (ANI) (Device)
Outcomes
Primary Outcomes
Mean End-Tidal Desflurane Concentration
Time Frame: From induction of anesthesia to end of surgery (approximately 60 minutes)
The average end-tidal desflurane concentration (Vol%) during maintenance of general anesthesia, measured using continuous gas monitoring. Desflurane delivery is titrated based on ANI (Analgesia/Nociception Index) in the intervention group and based on vital signs in the control group.
Secondary Outcomes
- Emergence Time(At the end of surgery until eye opening (approximately 5-15 minutes))
- Post-Anesthesia Care Unit (PACU) Length of Stay(From PACU entry to PACU discharge criteria fulfillment (approximately 30-90 minutes))
- Additional Analgesic Requirement in PACU(During PACU stay (up to 2 hours after surgery))
- Incidence of Postoperative Nausea and Vomiting (PONV)(Within 2 hours after surgery)
- Patient Satisfaction(At PACU discharge and 24 hours postoperatively (POD1))
Investigators
Cheol Lee,MD,PhD,
Professor
Wonkwang University Hospital