Ketamine Effect After Laparoscopic Gastric Reduction: A Randomized, Double-Blinded, Placebo Controlled Study

Study Overview
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Brief Summary
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Laparoscopic surgery for gastric reduction is frequently associated with high levels of postoperative pain. Postoperative pain is very often treated with opioids. However large doses of opioids can result in respiratory depression with hypoxemia especially in high risk patients with obstructive sleep apnea. since a large group of patients undergoing surgery for gastric reduction surgery also have obstructive sleep apnea, it is expected that these patients are also at high risk for postoperative respiratory depression and hypoxemia. Intraoperative ketamine has been used as an effective multimodal agent to reduce postoperative pain. However, ketamine alone has not been examined to improve postoperative pain outcomes in patients undergoing gastric reduction surgery. More importantly, it is unknown if the use of intraoperative ketamine can lead to better overall quality of recovery in the same patient population. In addition, ketamine has been shown to improve ventilation but it remains to be determined if the intraoperative use of ketamine will result in less postoperative hypoxemic events. The main objective of the current investigation is to examine the effect of intraoperative ketamine on postoperative quality of recovery after gastric reduction surgery. The investigators hypothesize that subjects receiving ketamine will have a greater global quality of recovery score than the ones receiving saline.

Official Title
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Ketamine Effect on Recovery and Respiratory Outcomes After Laparoscopic Gastric Reduction: A Randomized, Double-Blinded, Placebo Controlled Study

Conditions
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Pain, Obesity, Hypoxia

Intervention / Treatment
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* Drug: Ketamine
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-64 surgery: laparoscopic gastric reduction (gastric sleeve or gastric bypass) ASA physical status classification I, II, III Body Mass Index >35kg/m2 Fluent in English Exclusion Criteria: History of allergy to protocol medications History of chronic opioid use Pregnant patients Drop out: Conversion to an open surgical route, patient or surgeon request.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 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 |
| --- | --- |
| Active Comparator: Group K (Ketamine)<br>Group K (ketamine) will receive 0.5mg /kg of ketamine bolus followed by an infusion of 0.5 mg/kg/hour of ketamine throughout the intraoperative period (Adjusted body weight). | Drug: Ketamine<br>* Group K (ketamine) will receive 0.5mg /kg of ketamine bolus followed by an infusion of 0.5 mg/kg/hour of ketamine throughout the intraoperative period (Adjusted body weight).<br>* Other names: Ketalar;|
| Placebo Comparator: Group P (Placebo)<br>Group P (placebo) will receive the same amount of saline. | Drug: placebo<br>* Group P (placebo) will receive the same amount of saline.<br>* Other names: Sterile .9 Normal Saline;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of Recovery 40 | Scores on QOR (quality of recovery) 40 questionnaire. The QoR-40 score, which ranges from 40 to 200, representing very poor (low scores) to outstanding quality of recovery (high scores), respectively. | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Opioid Consumption | Total number of opioids (morphine equivalents) consumed 24 hours after surgery | 24 hours | 
| Postoperative Pain Scores | Participants pain scores will be recorded at 24 hours after surgery. Pain scores range from 0 (no pain) to 10 (worst pain imaginable). | 24 hours | 
| Length of Hospital Stay | The subjects length of hospital stay will be recorded. Length of stay is defined as day of surgery to date of discharge from the hospital which may be up to 2 weeks.. | Up to 2 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Quality of Recovery 40 Questionaire, Pain, Hypoxia, Gastric Surgery, Obesity, Ketamine