Postoperative Subtenons Anesthesia for Postoperative Pain in Pediatric Strabismus Surgery

Study Overview
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Brief Summary
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The purpose of this study is to determine if local anesthetic, either a subtenons injection (an injection just beneath the surface tissue of the eye) or a topical ophthalmic gel (applied directly on the surface of the eye) given at the end of strabismus surgery reduces postoperative pain. Some surgeons routinely use either the subtenon and/or topical anesthetic for pain at the end of strabismus surgery.

Official Title
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Postoperative Subtenons Anesthesia for Postoperative Pain in Pediatric Strabismus Surgery

Conditions
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Strabismus

Intervention / Treatment
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* Drug: subtenons anesthetic - preservative-free bupivacaine 0.75%
* Drug: topical anesthetic - 0.5 cc of lidocaine 3.5% ophthalmic gel
* Drug: topical control - 0.5 cc of Hypromellose 0.3% gel
* Drug: subtenons control - 0.5 cc of Normal Saline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 1 year to < 8 years Undergoing strabismus surgery under general anesthesia No previous surgery on muscle to be operated No known allergy to lidocaine or bupivacaine Investigator willing to inject subtenons NS or preservative-free bupivacaine 0.75% by cannula into all surgical wounds and willing to administer topical lidocaine 3.5% ophthalmic gel or Hypromellose 0.3% gel (GenTeal Severe Dry Eye Relief) to all surgical wounds at the end of strabismus surgery.

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 7 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: subtenons anesthetic and topical control<br>Group 1 (subtenons anesthetic and topical control): 0.5 cc of local anesthetic (preservative-free bupivacaine 0.75%) administered via a cannula subtenons through each surgical wound with 0.5 cc of Hypromellose 0.3% gel applied topically to each surgical wound at end of surgery | Drug: subtenons anesthetic - preservative-free bupivacaine 0.75%<br> <br> Drug: topical control - 0.5 cc of Hypromellose 0.3% gel<br> <br> |
| Other: topical anesthetic and subtenons control<br>Group 2 (topical anesthetic and subtenons control): 0.5 cc of lidocaine 3.5% ophthalmic gel applied topically to each surgical wound and 0.5 cc of normal saline (NS) administered via a cannula subtenons through each surgical wound at end of surgery | Drug: topical anesthetic - 0.5 cc of lidocaine 3.5% ophthalmic gel<br> <br> Drug: subtenons control - 0.5 cc of Normal Saline<br> <br> |
| Other: topical control and subtenons control<br>Group 3 (topical control and subtenons control): 0.5 cc of topical Hypromellose 0.3% gel applied topically to each surgical wound and 0.5 cc of NS administered via a cannula subtenons through each surgical wound at end of surgery | Drug: topical control - 0.5 cc of Hypromellose 0.3% gel<br> <br> Drug: subtenons control - 0.5 cc of Normal Saline<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average Pain Score Over the First 30 Post-operative Minutes Using the CHEOPS Scale | Pain will be assessed by a masked observer using the Children's Hospital Eastern Ontario Pain Scale (CHEOPS) scale. The CHEOPS (Children's Hospital of Eastern Ontario Pain Scale) is a behavioral scale for evaluating postoperative pain in young children. The scale is assessed using the sum of a score for cry (1-3), facial expression (0-2), verbalization (0-2), torso (1-2), touch (1-2) and legs (1-2). The minimum score is 4, the maximum score is 13, and higher scores indicate more pain. Pain is rated every 5 minutes for the first 30 minutes postoperatively. Each pain score collected in the first 30 minutes was averaged to calculate a per per participant average pain score over the first 30 minutes . Then each participant's per participant average pain score was combined to calculate the reported mean for Average pain score over the first 30 post-operative minutes using the CHEOPS scale. for each group. | 0-30 minutes post-operative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak Pain Score | This secondary outcome will include the peak pain score for duration of follow up period. Pain will be assessed by masked observers, using the CHEOPS scale. The CHEOPS (Children's Hospital of Eastern Ontario Pain Scale) is a behavioral scale for evaluating postoperative pain in young children. The scale is assessed using the sum of a score for cry (1-3), facial expression (0-2), verbalization (0-2), torso (1-2), touch (1-2) and legs (1-2). The minimum score is 4, the maximum score is 13, and higher scores indicate more pain. A pain score was assessed and recorded every 5 minutes by a masked observer (clinical research coordinator) for the first 30 minutes after extubation, then every 15 minutes for the next hour, then, if applicable, hourly until discharge. | 0-150 minutes post-operative | 
| Total Narcotic Use During Post-operative Recovery | This secondary outcome will include total narcotic use | Total time in post-operative recovery - up to 6 hours | 
| Negative Postoperative Behavior Score on the PHBQ (Post Hospitalization Behavioral Questionnaire) | This secondary outcome will determine the negative postoperative behaviors based on the PHBQ questionnaire given to the parents of the child 1 week (+/- 3 days) post-operatively. with a score of 81 indicating no change, a score of less than 81 indicating a change for the better, and a score of over 81 indicating a change for the worse, on average, in behavior. Lowest score 27; highest score 135 | 1 week (+/- 3 days) post operatively | 
| Average Time to Discharge |  | 0-150 minutes post-operative | 
| Number of Participants With Post Operative Nausea and Vomiting |  | 0-150 minutes post-operative | 
| Number of Participants Who Required Anti-emetic Medication Post-operatively |  | Total time in post-operative recovery - up to 6 hours | 
| Peak Pain Score During First 30 Minutes | This secondary outcome will include the peak pain score for duration of follow up period. Pain will be assessed by masked observers, using the CHEOPS scale. The CHEOPS (Children's Hospital of Eastern Ontario Pain Scale) is a behavioral scale for evaluating postoperative pain in young children. The scale is assessed using the sum of a score for cry (1-3), facial expression (0-2), verbalization (0-2), torso (1-2), touch (1-2) and legs (1-2). The minimum score is 4, the maximum score is 13, and higher scores indicate more pain. Pain is rated every 5 minutes for the first 30 minutes postoperatively. | 0-30 minutes post-operative |