An observational study in Surgery and Shoulder Impingement, sponsored by Tri-Service General Hospital. Completed at 1 site in Taiwan. Open to participants aged 20 Years to 85 Years. Per ClinicalTrials.gov, last updated 2024-05-03.
Sponsored by Tri-Service General Hospital · Observational
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?
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?
304 studies on the registry are indexed under Shoulder Impingement Syndrome; 55 are open to participants now.
This study's enrollment of 40 is below the median of 60 across 39 observational studies indexed under Shoulder Impingement Syndrome.
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Patients scheduled to undergo shoulder rotators repair surgery
Exclusion Criteria:
Patients scheduled to undergo shoulder rotators repair surgery
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
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 .
Time frame: After induction of anesthesia and before surgical incision
Difference Between Intraoperative Pupillary Pain Index (PPI) and Postoperative Numerical Pain Scale (NRS)
1. 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. 2. 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).
Time frame: From emergency of anesthesia to early Post-anesthesia period
| Milestone | Shoulder Rotators Repair |
|---|---|
| Started | 40 |
| Completed | 37 |
| Not completed | 3 |
| Withdrew: Protocol violation | 1 |
| Withdrew: Surgery canceled | 1 |
| Withdrew: Interscalene brachial block not performed | 1 |
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 .
| score on a scale | Shoulder Rotators Repair |
|---|---|
| ISB side | 1.8 ± 0.2 |
| Control side | 6.6 ± 0.3 |
1. 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. 2. 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).
| score on a scale | Shoulder Rotators Repair |
|---|---|
| intraoperative PPI | 1.5 ± 0.2 |
| postoperative NRS | 1.7 ± 1.3 |
Collected over 2 days. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Shoulder Rotators Repair | 0/34 (0%) | 0/34 (0%) | 0/34 (0%) |
40 patients scheduled for rotator cuff surgery were recruited for this study. Of these, three did not follow the study protocol: one had canceled surgery, one did not undergo ISB, and in one case, sevoflurane was not used as the main anesthetic. For the remaining 37 patients, Three patients did not report a loss of subjective cold/pinprick sensation in the C5 and C6 dermatomes, indicating an unsuccessful block. Therefore, 34 patients were included in the final analysis.
| Age, Continuous(years old) | Shoulder Rotators Repair |
|---|---|
| Mean | 62 ± 11 |
| Sex: Female, Male(Participants) | Shoulder Rotators Repair |
|---|---|
| Female | 21 |
| Male | 13 |
| Race and Ethnicity Not Collected(Participants) | Shoulder Rotators Repair |
|---|
| Region of Enrollment(participants) | Shoulder Rotators Repair |
|---|---|
| Taiwan | 34 |
| Body Mass Index (BMI)(kg/m^2) | Shoulder Rotators Repair |
|---|---|
| Mean | 24.1 ± 2.7 |
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Tri-Service General Hospital