Opioid sparing anesthesia is extremely important in the post-operative obese population.
With more and more obese patients entering the operating room a multi-modal approach to
analgesia is crucial. Finding effective alternatives to opioid therapy is the rationale of
this proposal. Literature involving ketamine and magnesium in bariatric surgical patients is
1. Patient will be identified by surgeon and consented by member of the research team
2. Patient will be randomized to one of three groups on the day of surgery
3. Following securement of the endotracheal tube, the study medication will be
administered over 10 minutes via an IV infusion pump.
4. The subject will receive ketamine, ketamine plus magnesium or a placebo.
5. Following surgery, the patient will be taken to the post anesthesia care unit (PACU)
and set up with standard ASA monitoring as well as end-tidal CO2 via nasal cannula. A
hydromorphone patient controlled analgesia (PCA) pump will be set-up by nursing and
given to the patient. Standard dosing of 0.2 mg bolus, every 6 minutes with a maximum 2
mg will be the starting dose as is standard for these patients post-operatively.
6. Primary outcome will be the total amount of hydromorphone used in the first 24 hours
1. Subjects undergoing laparoscopic sleeve gastrectomy
2. Consenting adults age 18-80
3. ASA II to ASA III
4. Ability to understand and use a PCA
5. Required to be hospitalized for at least 24 hours post-op
1. Patient refusal
2. Chronic opiate use (daily opiate use for >3 months)
3. Chronic Kidney disease (Creatinine>2)
4. Known allergy or adverse effect of ketamine, magnesium or hydromorphone
5. Patients with documented psychiatry (Maniac or MDP) history
6. Patient unable to give informed consent
7. Patient with limited or no English fluency