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ANI-guided Intraoperative Analgesia in Low-pressure Anesthesia

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT04319913
Recruitment Status : Not yet recruiting
First Posted : March 24, 2020
Last Update Posted : March 24, 2020
Information provided by (Responsible Party):
Chien-Chung,Huang, Mackay Memorial Hospital

Brief Summary:
During functional endoscopic sinus surgery(FESS), low-pressure anesthesia is often applied, aiming to decreased operative blood loss, and anesthetics, narcotics and antihypertensive agents are given to achieve desirable low blood pressure. However, the dose of these medications given is usually decided subjectively based on the clinical experience of the care provider, placing the patient in a risky situation of narcotics overdosing or underdosing. Therefore, here is the question: Whether intraoperative analgesia guided by an objective pain monitoring device, such as the Analgesia Nociception Index (ANI), could decrease the amount of narcotics, other anesthetic agents, and blood loss in patients undergoing low-pressure anesthesia.

Condition or disease Intervention/treatment Phase
Analgesia Functional Endoscopic Sinus Surgery Heart Rate Variability Opioid Consumption Device: analgesia nociception index Not Applicable

Detailed Description:

Analgesia nociception index (ANI) is an objective pain monitoring device, it could measure parasympathetic tone base on heart rate variability analysis, which is a way to measure the effect of respiratory sinus arrhythmia on heart rate. In the previous studies, ANI had been used to predict immediate postoperative pain, intraoperative analgesia in children, and intraoperative analgesia in bariatric surgery, which showed ANI can be used to detect surgical stimuli, reduce intraoperative consumption of narcotics, and assess immediate postoperative pain intensity. However, no publication has mentioned ANI been used in low-pressure anesthesia.

Participants with ASA physical status class I or II, age between 20-65, and body mass index less than 35 who would undergo FESS are enrolled and randomly allocated by using computer-generated random number table into two groups with equal probability: ANI-guided remifentanil titration or remifentanil titration by standard care. Total intravenous anesthesia with propofol TCI(target controlled infusion) and remifentanil TCI are used for anesthesia maintenance, targeting bispectral index between 40 and 60. The ANI value in experimental group would be maintained between 50 and 70. Intraoperative mean arterial pressure (MAP) would be targeted at 55-65 mmHg, and calcium channel blocker would be administered if MAP could not achieve target despite of propofol and remifentanil titration.

Participant's demographics, baseline information, type and duration of the operation, duration from end of the surgery till participant awaken, ANI value, vital signs, the amount of narcotics, anesthetics and antihypertensive medications used, intraoperative blood loss, surgeon's satisfaction to the operation field, participant first recorded pain score in postoperative recovery room using visual analogue scale, and opioid-associated side effects such as nausea, vomiting, pruritis, dizziness in postoperative recovery room, will be recorded and analyzed. The statisticians will apply Chi-square for categorical data, T-test for continuous data, and multiple regressions analysis. P value less than 0.05 was considered statistically significant. Using G-power software to estimate, predicted sample size is 120 presuming type I error 0.05, power 0.95, and medium effect size.

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 120 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Masking Description: The analgesia nociception index sensors are a pair of patches. They would be placed on the participant's right shoulder and the left side of the chest before the induction of general anesthesia, recording the ANI value throughout the operation. In the control group, the ANI monitor would be covered up, so that the care provider could only titrate remifentanil based on clinical experience. The participants would be masked from which group they were allocated into. The surgeon would be masked from the participant's allocation, and surgeon's satisfaction to the operation field would be surveyed by a questionnaire right after the operation, also the estimated blood loss amount would be recorded by the same surgeon.
Primary Purpose: Treatment
Official Title: Whether Intraoperative Analgesia Guided by the Analgesia Nociception Index (ANI) Can Decrease the Amount of Narcotics, Other Anesthetic Drugs, and Blood Loss in Patients Undergoing Low-pressure Anesthesia: a Randomized Controlled Trial
Estimated Study Start Date : July 1, 2020
Estimated Primary Completion Date : July 1, 2023
Estimated Study Completion Date : July 1, 2023

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Experimental: ANI-guided
ANI-guided narcotics use to maintain ANI value between 50 to 70
Device: analgesia nociception index
Analgesia nociception index (ANI) could objectively monitor how pain the participant is. In the experimental group, the care provider would decrease the dose of narcotics (remifentanil) if the ANI value is above 70, and increase the dose if the ANI value is under 50.

No Intervention: Control
narcotics use guided by clinical experience, ANI is still recorded but would be covered up intraoperatively

Primary Outcome Measures :
  1. Narcotics consumption [ Time Frame: From the first given dose of remifentanil until the last given given dose of remifentanil during anesthesia, assessed up to 8 hours. ]
    Remifentanil would be used as narcotics, the total amount used intraoperatively would be recorded

Secondary Outcome Measures :
  1. Anesthetics consumption [ Time Frame: From the first given dose of anesthetics (propofol or midazolam, whichever comes first) until the last given given dose of anesthetics (propofol or midazolam, whichever comes last), assessed up to 8 hours. ]
    The amount of anesthetics (mainly propofol) used intraoperatively would be recorded

Other Outcome Measures:
  1. Blood loss [ Time Frame: the estimated blood loss would be recorded immediately after the operation ]
    Blood loss would be estimated by surgeon

  2. Bleeding of the operation field [ Time Frame: The questionnaire would be provided to the surgeon immediately after the operation ]

    Bleeding of the operation field would be surveyed to surgeons by a questionnaire.

    The clarity of operation field:

    1. Minimal bleeding: no need of suction.
    2. Slightly bleeding: suction sometimes.
    3. Moderate bleeding: Suction frequently
    4. Severe bleeding: surgical field compromised even right after suction
    5. Continuous bleeding.

Information from the National Library of Medicine

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Ages Eligible for Study:   20 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • ASA physical status class I or II
  • age between 20-65
  • body mass index less than 35
  • scheduled for functional endoscopic sinus surgery

Exclusion Criteria:

  • major cardiovascular disease, arrhythmia, respiratory disease, cerebral vascular disease, or ASA physical status classification III or greater
  • documented or self-reported history of chronic pain
  • acute or chronic opioid analgesic use
  • dysautonomia
  • diabetes mellitus with evidence of neuropathy
  • emergency cases
  • allergy to medications in the study

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04319913

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Contact: Chien-Chung Huang, MD +886225433535 ext 3009

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MacKay Memorial Hospital
Taipei, Taiwan, 104
Sponsors and Collaborators
Mackay Memorial Hospital
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Study Director: Chien-Chung Huang, MD Mackay Memorial Hospital
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Responsible Party: Chien-Chung,Huang, Attending physician of anesthesiology , Principal Investigator, Mackay Memorial Hospital Identifier: NCT04319913    
Other Study ID Numbers: 20MMHIS069e
First Posted: March 24, 2020    Key Record Dates
Last Update Posted: March 24, 2020
Last Verified: March 2020
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

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Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Chien-Chung,Huang, Mackay Memorial Hospital:
analgesia nociception index
functional endoscopic sinus surgery
opioid consumption
heart rate variability
low pressure anesthesia
Additional relevant MeSH terms:
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Perceptual Disorders
Neurobehavioral Manifestations
Neurologic Manifestations
Nervous System Diseases
Signs and Symptoms