Pupillary Pain Index to Evaluate Interscalene Block and Postoperative Pain in Patients Underwent Shoulder Surgery

Surgery Clinical Trial

Official title:

Department of Anesthesiology, Tri-Service General Hospital and National Defense Medical Center , Taipei, Taiwan

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05590767
• Other study ID #: C202205095
• Status: Completed
• Start date: October 27, 2022
• Est. completion date: August 31, 2023

Study information

• Verified date: May 2024
• Source: Tri-Service General Hospital
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

When an individual encounters nociceptive pain stimuli, the pupil dilates in a unique manner known as Pupil reflex dilation (PRD).The degree of pupillary reflex dilatation can be further quantified into an objective parameter, termed the Pupillary pain index (PPI), as a monitoring tool for the balance between nociception and antinociception in surgical patients The motivation for this study is to investigate the feasibility of using pupillometry to assess acute pain after shoulder surgery. The purpose of the study is as follows: (1) Can PDR in patients undergoing general anesthesia be used to assess the analgesic effect of interscalene block? (2) Does PPI at the end of surgical anesthesia in such patients correlate with the first numerical pain scale (NRS) during the recovery room?

Description:

When an individual encounters nociceptive pain stimuli, the pupil dilates in a unique way called pupillary reflex dilation (PRD), which can be observed both when the individual is awake or under anesthesia. The degree of pupillary reflex dilatation can be further quantified into an objective parameter called the Pupillary pain index (PPI), which serves as a monitoring tool for the balance between nociception and antinociception in surgical patients. Larson studied 32 female breast surgery patients who received general anesthesia combined with thoracic paravertebral nerve block on the affected side. The results showed that the affected side of the nerve block had significantly lower pupillary reflex dilation than those without nerve block on the healthy side of the breast. The authors believed that this study confirmed the value of pupillary reflex dilation in monitoring the success rate of unilateral thoracic paravertebral nerve block during general anesthesia. In a prospective observational study of 26 patients undergoing neurosurgery under general anesthesia, Pupillary pain index at the end of surgical anesthesia and Numerical Rating Scale (NRS) during the recovery room were recorded separately, The results showed a significant correlation between the two parameters (rS = 0.62; P = 0.002). The authors concluded that the application of the measurement of pupillary reflex dilation may be useful in predicting and preventing acute postoperative pain. Shoulder rotator muscle repair is a common surgery in our hospital. Patients must receive general anesthesia, sometimes combined with scalene interscalene block (ISB), to improve postoperative acute pain ,help to perform passive shoulder rehabilitation exercises and prevent shoulder joint adhesions. Based on the above literature review, the motivation for this study was to investigate the feasibility of using pupillometry to assess acute pain after shoulder surgery. The objectives of the research project are as follows: 1. Can pupillary reflex dilation in patients undergoing general anesthesia be used to assess the analgesic effect of scalene nerve block? 2. Is the pupillary pain index (PPI) at the end of surgical anesthesia correlated with the first numerical pain scale (NRS) during the recovery room in such patients?

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: August 31, 2023
• Est. primary completion date: August 17, 2023
• Accepts healthy volunteers: No
• Gender: All
• Age group: 20 Years to 85 Years

Eligibility

Inclusion Criteria:

• Patients who received general anesthesia combined with ipsilateral interscalene block

• Patients listed as a Class I/II physical condition of the American Society ofAnesthesiologists

Exclusion Criteria:

• Patients younger than 20 years of age

• The presence of ophthalmologic (recent eye surgery or cataracts) or neurologic diseases (diabetic neuropathy,or postherpetic neuralgia) that could interfere with Pupillometer

Related Conditions & MeSH terms

• Shoulder Impingement
• Shoulder Impingement Syndrome
• Surgery

Intervention

Procedure:
• Patients scheduled to undergo shoulder rotators repair surgery
Patients scheduled to undergo shoulder rotators repair surgery, and received combined general anesthesia and interscalene block

Locations

Country	Name	City	State
Taiwan	Department of Anesthesiology, Tri-Service General Hospital	Taipei

Sponsors (1)

Lead Sponsor	Collaborator
Tri-Service General Hospital

Country where clinical trial is conducted

Taiwan, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Pupillary Pain Index (PPI )	The primary outcome is the difference of the pupillary pain index (PPI ) between the ISB side and the control side The PPI mode applies a standardized, incremental transcutaneous electrical stimulation (100 Hz, 10-60mA, with 1-s intervals) that progressively increases in intensity until a pupil dilation of >13% is observed. The degree of reflex dilation is quantified on a scale of 1 (very deep analgesia) to 9 (very light analgesia) and referred to as the PPI .	After induction of anesthesia and before surgical incision
Secondary	Difference Between Intraoperative Pupillary Pain Index (PPI) and Postoperative Numerical Pain Scale (NRS)	PPI: The PPI mode applies a standardized, incremental transcutaneous electrical stimulation (100 Hz, 10-60mA, with 1-s intervals) that progressively increases in intensity until a pupil dilation of >13% is observed. The degree of reflex dilation is quantified on a scale of 1 (very deep analgesia) to 9 (very light analgesia) and referred to as the PPI.; NRS: the nursing staff in the post-anesthesia care unit asked the patient to rate their pain at the surgical site using the NRS, with a range of 0(no pain)-10(most severe pain).	From emergency of anesthesia to early Post-anesthesia period