Comparison of Cumulative Opioid Consumption Between Variable-Rate Feedback Infusion and Fixed-Rate Basal Infusion Modes of Intravenous PCA Following Mixed Surgery

Prospective Randomized Controlled Study of Individualized PCA Model Based on Multi-dimensional Strategies (Cumulative Opioid Consumption Between Variable-Rate Feedback Infusion and Fixed-Rate Basal Infusion Modes)

Perioperative pain management affects patient recovery. However, the rate of moderate to severe postoperative pain is as high as 73.8%, which hinders recovery and increases the risk of complications. Although opioids are the first-line analgesics, excessive use leads to adverse reactions. The traditional fixed-rate PCA mode is difficult to match the changes in postoperative pain. This study will compare different PCA mode optimization strategies, assuming that they can reduce opioid dosage, improve analgesic effect, and reduce adverse reactions, providing high-quality evidence-based basis for postoperative analgesia and promoting individualized and intelligent management.

Study Overview

• Status: Recruiting
• Conditions: Surgery; Pain Management; Patient-controlled Analgesia; Opioid Consumption
• Intervention / Treatment: Procedure: Fixed-rate basal infusion mode; Procedure: Variable-rate feedback infusion mode

Detailed Description

Perioperative pain management significantly impacts patient recovery outcomes. However, the incidence of moderate to severe postoperative pain remains high at 80%, which impedes recovery and increases complication risks. Although opioids serve as first-line analgesics, excessive use causes numerous adverse reactions. The traditional fixed-rate Patient-Controlled Analgesia (PCA) mode fails to adapt to dynamic postoperative pain variations. This study will compare different PCA optimization strategies, hypothesizing that these approaches can reduce opioid dosage, enhance analgesic effectiveness, and minimize adverse reactions. The research aims to provide evidence-based foundations for postoperative analgesia, promoting individualized and intelligent pain management systems that better serve patient needs throughout recovery.

• Study Type: Interventional
• Enrollment (Estimated): 1170
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Fang Luo; Phone Number: 13611326978; Email: 13611326978@163.com

Study Locations

• China
  • Beijing, China
    • Recruiting
    • Beijing Tiantan Hospital, Beijing, Beijing 100070
    • Contact: Fang Luo; Phone Number: 13611326978; Email: 13611326978@163.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• aged between 18 to 65 years;
• American Society of Anesthesiologists physical status Ⅰ - Ⅲ;
• Patients scheduled for elective mixed surgery were enrolled. Mixed surgeries included thoracic, abdominal, spinal, orthopaedic, and cranial procedures performed using either minimally invasive or open approaches.

Exclusion Criteria:

• Allergy to PCA medications;
• Presence of chronic pain syndromes;
• Presence of psychiatric disorders, or severe cardiovascular, cerebrovascular, renal, or hepatic dysfunction.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Fixed-rate basal infusion mode group	Procedure: Fixed-rate basal infusion mode; All participants received a standardized PCA solution containing sufentanil (100 μg), ondansetron (16 mg), and normal saline with total volume 100 mL. In conventional fixed-rate basal infusion mode group, the PCA was set to administer a bolus of 2 mL with a lock out interval of 15 minutes and background infusion rate 2 mL/h.
Experimental: Variable-rate feedback infusion mode group	Procedure: Variable-rate feedback infusion mode; All participants received a standardized PCA solution containing sufentanil (100 μg), ondansetron (16 mg), and normal saline with total volume 100 mL. In variable-rate feedback infusion mode group, a bolus of 2 mL with a lock out interval of 15 minutes and background infusion rate 2 mL/h, which increased to 2.5 mL/h, was used whenever the demand dose was administered within lock out interval. The background infusion rate automatically decreased by 0.5 mL/h when the bolus button was not pressed for 1 hour. The background infusion rate was limited to a maximum of 12.0 mL/h and a minimum of 1 mL/h. The specific variable-rate feedback infusion mode setting was based on previous research, and the opinions of manufacturers and researchers to ensure patient safety and to provide effective analgesia.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total cumulative opioid consumption	The total cumulative opioid consumption includes sufentanil delivered via PCA and opioid-equivalent rescue analgesics.	at 48 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Resting and movement pain score was assessed by NRS	NRS ranges from 0 to 10, with the highest score indicating the worst pain.	At 1, 6, 12, 24, and 48 hours postoperatively
Quality of sleep	Quality of sleep was evaluated on postoperative days 1, 2 and 3 using the Medical Outcomes Study Sleep Scale (MOS). MOS is questionnaire comprising 12 items that assess various aspects of sleep using a 6-point ordinal scale (1 indicating permanence and 6 indicating absence).	At 24, and 48 hours postoperatively
The degree of nausea and vomiting	The degree of nausea and vomiting, a score from 0 to 10 was given. A score of 0 was given if the patient had no nausea or vomiting, and a score 10 was given if the patient had severe nausea and vomiting.	At 12, 24, and 48 hours postoperatively
Cumulative PCA volume consumption		Within the first 48 hours postoperatively
Number of additional rescue analgesics		within 48 hours postoperatively
Dosage of additional rescue analgesics		within 48 hours postoperatively
Postoperative quality of recovery	Postoperative quality of recovery was assessed through the Postoperative Quality of Recovery-15 questionnaire 1 day after surgery. It consists of six domains (physiologic, nociceptive, emotive, activities of daily living, cognitive and overall patient perspective). The score ranges from 0 to 150, with higher score indicating a better quality of postoperative recovery.	At 24 hours postoperatively
The level of sedation and agitation	The level of sedation and agitation was assessed using the Richmond Agitation and Sedation Scale, which ranges from +4 (combative agitation) to -5 (deep sedation), with a score of 0 indicating an alert and calm state.	within 48 hours postoperatively
The patient's satisfaction with PCA	The patient's satisfaction with PCA during 2 days postoperatively was assessed according to the following scale: 1, very satisfactory; 2, satisfactory; 3, neutral; 4, unsatisfactory; 5; very unsatisfactory.	At 48 hours postoperatively

Collaborators and Investigators

• Sponsor: Beijing Tiantan Hospital
• Collaborators: Shenzhen University General Hospital; The Second Affiliated Hospital of Hainan Medical University; Youjiang Medical College for Nationalities

Publications and helpful links

Helpful Links

• Mitra S, Carlyle D, Kodumudi G, Kodumudi V, Vadivelu N. New Advances in Acute Postoperative Pain Management. Curr Pain Headache Rep. 2018;22(5):35.
• Momeni M, Crucitti M, De Kock M. Patient-controlled analgesia in the management of postoperative pain. Drugs. 2006;66(18):2321-37.
• Jung KT, So KY, Kim SU, Kim SH. The Optimizing Background Infusion Mode Decreases Intravenous Patient-Controlled Analgesic Volume and Opioid Consumption Compared to Fixed-Rate Background Infusion in Patients Undergoing Laparoscopic Cholecystectomy: A Pro

Study record dates

Study Major Dates

• Study Start (Actual): December 30, 2025
• Primary Completion (Estimated): October 30, 2027
• Study Completion (Estimated): December 30, 2027

Study Registration Dates

• First Submitted: December 22, 2025
• First Submitted That Met QC Criteria: January 22, 2026
• First Posted (Actual): January 23, 2026

Study Record Updates

• Last Update Posted (Actual): May 14, 2026
• Last Update Submitted That Met QC Criteria: May 12, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Neurobehavioral Manifestations; Perceptual Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Agnosia
• Other Study ID Numbers: KY2025-387-02-1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data that underlie the results reported in this article, after de-identification (text, tables, figures and appendices) are available. Derived data supporting the findings of this study are available from the corresponding author Fang Luo on request.

Drug and device information, study documents

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