90% Effective Infusion Time of Sufentanil to Prevent Induction Cough: A Biased Coin Sequential Study

Determination of the 90% Effective Infusion Time of Sufentanil to Prevent Sufentanil-Induced Cough During General Anesthesia Induction in Young and Elderly Patients: A Biased Coin Design Up-and-Down Sequential Study

This single-center, prospective biased coin up-and-down sequential study aims to determine the 90% effective infusion time (ET90) of sufentanil to prevent sufentanil-induced cough (SIC) during the induction phase of general anesthesia in adults undergoing endotracheal intubation. Two age cohorts are studied separately: younger adults (<65 years) and older adults (≥65 years). The trial does not test superiority or between-group differences as the primary objective.

All participants receive sufentanil via a peripheral intravenous pump. The total sufentanil dose is fixed within each age cohort (young: 0.40 μg/kg; elderly: 0.30 μg/kg), while the pump injection time is adjusted using the biased coin up-and-down allocation method. SIC success is defined as no audible cough within a prespecified observation window from the start of the infusion until 2 minutes after infusion ends.

The primary outcome is the ET90 of sufentanil and its 95% confidence interval for each age cohort, estimated using centered isotonic regression with bootstrap confidence intervals. Approximately 120 patients will be screened to obtain at least 54 evaluable participants per cohort.

Study Overview

• Status: Not yet recruiting
• Conditions: Cough
• Intervention / Treatment: Drug: Sufentanil Citrate

Detailed Description

This is a single-center, prospective sequential study using a biased coin up-and-down allocation approach to determine the 90% effective infusion time (ET90) of sufentanil during the induction phase of general anesthesia to prevent sufentanil-induced cough (SIC). The study evaluates two age groups separately: younger adults (<65 years) and older adults (≥65 years).

Sufentanil will be administered intravenously via a infusion pump. Within each age cohort, the total sufentanil dose is predetermined, while the infusion time (rate) is adjusted based on the previous participant's outcome according to the biased coin up-and-down rule.

The primary success criterion is the absence of SIC during a prespecified observation period that starts at sufentanil infusion initiation and ends shortly after infusion completion during the induction phase. The primary outcome is the ET90, estimated for each age cohort with an appropriate statistical model using the observed infusion times and SIC outcomes.

Participants are screened before surgery based on age and general anesthesia requirements, and key comorbidities and contraindications are considered to reduce confounding. Safety is monitored throughout the induction phase and perioperative period, with attention to potential adverse events including hemodynamic instability and respiratory depression.

Approximately 120 patients are planned for enrollment to obtain sufficient evaluable participants in each cohort for ET90 estimation.

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shiyou Wei, Doc; Phone Number: 15601680288; Email: lovewishyou@tongji.edu.cn

Study Locations

• China
  • Hunan
    • Shaoyang, Hunan, China, 422000
      • Shaoyang University Affiliated First Hospital
      • Contact: Yadan Liu; Phone Number: 18229421255; Email: lyd26897@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• American Society of Anesthesiologists (ASA) physical status I-III
• Aged ≥18 ears old
• Scheduled for elective surgery requiring general anesthesia with tracheal intubation

Exclusion Criteria:

• Resting vital signs upon operating-room arrival: systolic blood pressure ≥160 mmHg, or diastolic blood pressure ≥100 mmHg, or heart rate ≥110 beats per minute.
• Anticipated difficult airway, requirement for rapid-sequence induction, or emergency surgery.
• Chronic cough, asthma, chronic obstructive pulmonary disease (COPD), bronchiectasis, active pulmonary disease, or upper respiratory tract infection within the preceding 2 weeks.
• Regular opioid use for more than 2 weeks within 6 months before surgery; or recent use of antitussive agents or other medications that may alter the cough reflex.
• Known history of allergy to study drug (sufentanil citrate).
• Pregnancy, lactation, psychiatric disorders, or individuals unable to communicate appropriately.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: N/A
• Interventional Model: Sequential Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Single Interventional Arm; All enrolled participants receive sufentanil citrate injection, infused via peripheral intravenous syringe pump during general anesthesia induction. Two independent age-defined sequential sub-cohorts are included within this single arm: Younger adult sub-cohort (<65 years): fixed sufentanil total dose 0.40 μg/kg actual body weight.; Older adult sub-cohort (≥65 years): fixed sufentanil total dose 0.30 μg/kg actual body weight. Within each sub-cohort, the sufentanil infusion time is adjusted sequentially by biased-coin up-and-down rule according to the previous participant's sufentanil-induced cough (SIC) outcome. No other prophylactic anti-cough medications are given during the SIC observation window. After completion of the observation period, standard general anesthesia induction will be performed according to institutional routine.

Drug: Sufentanil Citrate; Sufentanil citrate administered via peripheral intravenous syringe pump during general anesthesia induction. Fixed weight-based total dose within each age sub-cohort; infusion time varies according to biased-coin up-and-down sequential rules.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
90% effective infusion time (ET90) of sufentanil for preventing sufentanil-induced cough (SIC)	ET90 is defined as the shortest sufentanil infusion time achieving no SIC in 90% of participants, estimated separately for younger adults (<65 years) and older adults (≥65 years) using centered isotonic regression with bootstrap 95% confidence intervals. SIC is defined as any audible cough within the predefined observation window.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence and severity of sufentanil-induced cough (SIC)	SIC severity graded: mild (1-2 coughs), moderate (3-4 coughs), severe (≥5 coughs). Count of cough episodes and SIC incidence at each infusion-time level, reported separately for two age sub-cohorts.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Peri-induction hemodynamic changes	Hemodynamic changes recorded during sufentanil infusion observation window.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Hypotension	Hypotension is defined as systolic blood pressure < 90 mmHg or mean arterial pressure (MAP) < 60 mmHg.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Bradycardia	Bradycardia is defined as heart rate < 50 beats per minute.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Injection pain	Pain induced by drug injection, assessed immediately after intravenous drug administration.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Chest wall rigidity	Chest wall rigidity is defined as opioid-induced increased tone of thoracic and abdominal muscles leading to reduced chest-wall compliance and difficulty with manual or mechanical ventilation.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Respiratory depression	Respiratory depression is defined as the presence of at least one of the following: respiratory rate (RR) < 8 breaths per minute in adults; arterial oxygen saturation (SpO₂) < 90 mmHg despite oxygen supplementation; shallow, slow and ineffective ventilation accompanied by somnolence or reduced level of consciousness (excessive sedation); arterial blood gas showing PaCO₂ >50 mmHg together with pH <7.30.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Allergic reaction	Allergic reaction is defined as drug-mediated hypersensitivity manifestations occurring after intravenous injection, including skin rash, urticaria, flushing, bronchospasm, hypotension or other immune-mediated adverse events.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Dizziness	Dizziness is defined as a subjective sensation of light-headedness or unsteadiness reported by the subject following study drug administration.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Palpitation	Palpitation is defined as the subject-reported unpleasant awareness of abnormal or forceful heartbeats after study drug injection.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Hypoxemia	Peripheral oxygen saturation SpO₂ <92% on pulse oximetry.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)
Pruritus	Subject reports generalized or local pruritus after sufentanil administration.	From start of sufentanil infusion until 2 minutes after the end of sufentanil infusion (anesthesia induction period)

Collaborators and Investigators

• Sponsor: Shiyou Wei
• Collaborators: Shaoyang University Affiliated First Hospital, Shaoyang, Hunan Province, China
• Investigators: Principal Investigator: Xin Lv, Shanghai Pulmonary Hospital, School of Medicine, Tongji University

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): December 25, 2026
• Study Completion (Estimated): December 30, 2026

Study Registration Dates

• First Submitted: August 19, 2026
• First Submitted That Met QC Criteria: August 19, 2026
• First Posted (Actual): August 21, 2026

Study Record Updates

• Last Update Posted (Actual): August 21, 2026
• Last Update Submitted That Met QC Criteria: August 19, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: endotracheal intubation; sufentanil-induced cough; general anesthesia induction; infusion time
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Cough; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Piperidines; Fentanyl; Sufentanil
• Other Study ID Numbers: Shaoyang-002

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No