Prevention of Postoperative Nausea and Vomiting in Patients Undergoing Vitrectomy Under Local Anesthesia

Study Overview
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Brief Summary
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Vitreoretinal surgery is associated with a considerable incidence of postoperative nausea and vomiting (PONV), which is reported to be as high as 60%. Reasons for this high incidence may be the long duration of surgery and anesthesia and the high degree of manipulation of the eye. Postoperative vomiting after vitrectomy is an important risk factor for the onset of several complications, such as suprachoroidal hemorrhage, with disastrous visual consequences. To date there is no evidence as to the possible protective effect of anti-emetic therapy with regard to interventions of vitrectomy performed under local anesthesia. In this prospective, randomized, multicenter, double blind study, we evaluated the efficacy of Ondansetron alone, Dexamethasone alone and in combination in controlling nausea and vomiting in patients undergoing vitrectomy under local anesthesia.

Detailed Description
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Patients were randomly stratified to receive 1 of 4 prophylactic antiemetic treatments (3 pharmaceutical treatment and 1 placebo) in a double-blind manner at the start of the surgery and 15 minutes before the end of surgery. The syringes were prepared by a third, neutral person not involved in the perioperative care of the patient, immediately before the start of anesthesia. All vitrectomy surgeries were performed, in each unit,under local anesthesia by a retrobulbar block. Each patients was observed and treated during a period of 24 hours after the surgery. For patients who have nausea and vomiting despite the antiemetic prophylaxis, will be given a rescue dose of 4 mg ondansetron IV.

Official Title
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A Multicenter Randomized Trial to Evaluate the Efficacy and Safety of Three Different Prophylactic Treatments of Postoperative Nausea and Vomiting in Patients Undergoing Vitrectomy Under Local Anesthesia

Conditions
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Postoperative Nausea and Vomiting

Intervention / Treatment
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* Drug: PLACEBO
* Drug: Dexamethasone
* Drug: Ondansetron
* Drug: Dexamethasone + Ondansetron


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 or older with an American Society of Anesthesiologists (ASA) physical status of I to II Scheduled for vitrectomy under local anesthesia Exclusion Criteria: Hypersensitivity to study drug or rescue medication Preoperative score for nausea greater than 4 out of 10 points Subjects who suffer from chronic nausea and/or vomiting Severe hepatic insufficiency (Child-Pugh score > 9) Other antiemetic within 12 hours prior to surgery Patients unable to undergo a local anesthetic Subjects with clinically significant or unstable cardiac, respiratory, hepatic, renal, or other major organ system disease Psychotic illness or depression Addiction to illicit substances or alcohol Non-psychotic emotional disorders Pregnant or lactating Subjects who, in the opinion of the investigator, would experience an unacceptable risk from administration of study drug

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: PLACEBO Group<br>Received normal saline | Drug: PLACEBO<br>* received normal saline, intravenously<br>|
| Active Comparator: DEXAMETHASONE Group<br>Received 4 mg Dexamethasone. | Drug: Dexamethasone<br>* 4 mg, intravenously, at the start of surgery<br>|
| Active Comparator: ONDANSETRON<br>Received 4 mg Ondansetron | Drug: Ondansetron<br>* 4 mg, intravenously, 15 minutes before the end of surgery.<br>|
| Active Comparator: DEXAMETHASONE + ONDANSETRON<br>Received 4mg Dexamethasone + 4mg Ondansetron | Drug: Dexamethasone + Ondansetron<br>* 4 mg dexamethasone, intravenously at the start of surgery and 4 mg ondansetron intravenously 15 minutes before the end of surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Proportion of patients with Complete Response (no nausea, no vomiting, no retching, and no use of rescue medication) during the first 24 hours after surgery |  | 1-24 hours post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| • Standardized score of nausea and/or vomiting severity if PONV occurs. |  | 1-24 hours post-operatively | 
| • Pain score during the immediate post-operative period. |  | 1-24 hours post-operatively | 
| • Number of antiemetic rescue medications given postoperatively. |  | 1-24 hours post-operatively | 
| • Rates of known side effects. |  | 1-24 hours post-operatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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ondansetron, dexamethasone, vitrectomy, local anesthesia