Randomized Controlled Trial of the STEIN Protocol: A Neuroplastic Pain Education and Guided Breathing Intervention During Awake Cataract Surgery (SLin)

July 21, 2026 updated by: Shawn R. Lin, MD, MBA, University of California, Los Angeles

This randomized controlled trial evaluates whether a standardized perioperative neuroplastic intervention: the STEIN Protocol (Strategies and Techniques for Enhancing Integration and Neuroplasticity), consisting of pain neuroscience education, guided imagery, and paced breathing, reduces intraoperative analgesic and anxiolytic requirements.

Secondary outcomes include patient-reported pain, anxiety, satisfaction, and postoperative recovery following cataract surgery.

Reduced intraoperative sedative and analgesic requirements may reflect improved patient comfort and autonomic regulation while minimizing medication-related adverse effects.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

The STEIN Protocol is a randomized behavioral intervention designed to evaluate whether standardized, non-pharmacologic interventions can help patients have a more comfortable and safe surgical experience.

Cataract surgery provides a highly standardized operative model with minimal procedural variability, making it well suited for evaluating perioperative behavioral interventions while minimizing confounding from surgical complexity.

The intervention is based on contemporary models of pain neuroscience, which propose that cognitive appraisal, expectancy, autonomic regulation, and attentional processes influence pain perception independent of tissue injury.

Participants in the study will receive standard cataract surgery, with some patients also taking part in the STEIN Protocol. This includes watching a short educational video before surgery, following slow, guided breathing during the procedure, and practicing brief breathing exercises at home for one week after surgery. The intervention is designed to reduce sympathetic arousal and promote parasympathetic regulation through standardized paced breathing and guided cognitive attention.

The intervention is intended to modify cognitive appraisal, attentional focus, and autonomic regulation, thereby influencing pain perception throughout the perioperative period.

The study will compare pain levels, medication use, recovery, and patient satisfaction between groups to determine whether this standardized, scalable approach can improve the surgical experience and potentially benefit patients undergoing many types of surgery in the future.

We hypothesize that participants receiving the STEIN Protocol will require less intraoperative anxiolytic and analgesic medication while reporting lower pain, lower anxiety, and greater satisfaction than participants receiving standard care.

Surgical technique, anesthetic management, questionnaire administration, and postoperative follow-up will be standardized across study groups.

Adherence to each component of the intervention will be documented to assess intervention fidelity.

Study Type

Interventional

Enrollment (Estimated)

300

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • United States
    • California
      • Los Angeles, California, United States, 90025
        • Recruiting
        • Stein Eye Institute - University of California Los Angeles
        • Contact:
        • Principal Investigator:
          • Shawn R Lin, MD, MS, MBA

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Adults undergoing elective cataract surgery under topical anesthesia who are able to provide informed consent and complete study procedures.

Exclusion Criteria:

Inability to provide informed consent Inability to comply with study procedures Complex or combined cataract surgery General anesthesia Medical, neurologic, psychiatric, or respiratory conditions interfering with study participation Requirement for modified anesthetic protocols Inability to complete postoperative breathing exercises or follow-up assessments

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Control
Device: Control
Participants wear open-ear headphones during cataract surgery. Every 3 minutes, a voice will ask if the patient would like more relaxing medication or pain medication.
Experimental: Music + Guided Imagery
Music and Guided Imagery
Device: Music and Guided Imagery

Participants wear open-ear headphones during cataract surgery. Every 3 minutes, a voice will ask if the patient would like more relaxing medication or pain medication.

Participants receive the STEIN Protocol, consisting of preoperative pain neuroscience education, intraoperative audio-guided paced breathing and guided imagery, and postoperative home breathing exercises.

The open-ear headphones allow participants to hear and communicate with the surgeon and operating room staff at all times. The audio may be stopped at any time if requested or clinically indicated. No additional medications or medical procedures are administered as part of the intervention, and all other aspects of surgical and anesthetic care remain unchanged.
Experimental: Music Only
Device: Music Only

Participants wear open-ear headphones during cataract surgery. Every 3 minutes, a voice will ask if the patient would like more relaxing medication or pain medication.

Participants receive the music protocol, consisting of preoperative pain neuroscience education, intraoperative music, and postoperative home breathing exercises.

The open-ear headphones allow participants to hear and communicate with the surgeon and operating room staff at all times. The audio may be stopped at any time if requested or clinically indicated. No additional medications or medical procedures are administered as part of the intervention, and all other aspects of surgical and anesthetic care remain unchanged.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Total cumulative intraoperative dose of anxiolytic and analgesic medications (midazolam [mg], fentanyl [mcg], and additional rescue medications, recorded separately).
Time Frame: From initiation of surgery until completion of surgery.
From initiation of surgery until completion of surgery.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Iowa Satisfaction with Anesthesia Scale (ISAS)
Time Frame: Within 30 minutes of surgery completion
Validated clinical survey instrument
Within 30 minutes of surgery completion
Numeric Rating Scale pain score (0-10)
Time Frame: Within 30 minutes of surgery completion
Validated clinical survey instrument
Within 30 minutes of surgery completion
Amsterdam Preoperative Anxiety and Information Scale (APAIS)
Time Frame: 30 minutes prior to surgery
Validated clinical survey instrument
30 minutes prior to surgery
Additional questions
Time Frame: Within 30 minutes after surgery completion
Investigator-developed exploratory questionnaire evaluating perceived comfort, communication, perceived control, and overall surgical experience.
Within 30 minutes after surgery completion

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of California, Los Angeles

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

June 10, 2026

Primary Completion (Estimated)

September 1, 2026

Study Completion (Estimated)

September 1, 2026

Study Registration Dates

First Submitted

July 15, 2026

First Submitted That Met QC Criteria

July 15, 2026

First Posted (Actual)

July 20, 2026

Study Record Updates

Last Update Posted (Actual)

July 23, 2026

Last Update Submitted That Met QC Criteria

July 21, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • IRB-25-2639

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

YES

IPD Plan Description

De-identified individual participant data, study protocol, statistical analysis plan, informed consent form, and supporting study documents will be made available upon reasonable request following publication, subject to institutional review and IRB requirements.

IPD Sharing Time Frame

After publication for 1 year

IPD Sharing Access Criteria

The researcher can email the study PI to obtain the IPD.

IPD Sharing Supporting Information Type

  • STUDY_PROTOCOL
  • SAP
  • ICF
  • CSR

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Cataract

Clinical Trials on Control

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in New Zealand

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Subscribe