Morphine Consumption in the Obese Patients

Study Overview
=================
Brief Summary
-----------------
The goal of this observational study is to evaluate the quality of postoperative analgesia in a group of obese patients schedule to bariatric surgery under TIVA Opiod-free after to receive lidocaine and ketamine perfusion. The main question it aims to answer are: How lidocaine and ketamine perfusion during recovery period does impact over morphine consumption on the following 48 hours after surgery? All participants will receive total intravenous anesthesia and, at the end of the surgery, they will be divided in two groups, group A: placebo and, group B: with postoperative lidocaine and ketamine perfusion. Our hypothesis is ketamine and lidocaine are a good alternative to decrease the use of morphine in obese patients.

Detailed Description
-----------------
The obese patients have more risk for certain side effects and complications with elevated risk of perioperative mortality and morbidity. An effective postoperative pain management is important to prevent pulmonary complications and, it is not recommended continuous infusions of opioids in this kind of patients, because the opioid-induced upper airway obstruction and respiratory depression are more likely to be seen in obese patients with obstructive sleep apnea. We can reduce perioperative opioid using dexmedetomidine, ketamine and lidocaine, however, it is a little know the use and benefits of lidocaine and ketamine inmediately after surgery.

Official Title
-----------------
Post-operative Morphine Consumption in Obese Patients Undergoing Laparoscopic Bariatric Surgery Following Ketamina and Lidocaine Perfusion

Conditions
-----------------
Opioid Use, Pharmacological Action, Post Operative Pain, Obesity, Morbid, Anesthesia Morbidity

Intervention / Treatment
-----------------
* Drug: Control Group
* Drug: Placebo


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: All patients between 18 y 65 years old. IMC > 30 kg/m2 ASA II/III Exclusion Criteria: Patients taking high doses of opioids before operation for chronic pain Patients with allergies to any study medication. Pregnancy or breastfeeding. Kidney or heptic failure. Surgical complication

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Group A:<br>At the end of surgery, on the recovery room, this group will receive lidocaine (1 mg/kg/h) and Ketamine (0,15 mg/kg/h) for 90 minutes | Drug: Control Group<br>* At the end of surgery, they will continue receiving analgesia according the schedule and, addicionally, lidocaine (1 mg/kg/h) and Ketamine (0,15 mg/kg/h) for 90 minute as part of postoperative analgesia.<br>* Other names: Multimodal analgesia will be performed with paracetamol 1 gr, dexketoprofen 50 mg and metamizol 2 gr and morphine according to visual analogue scale;|
| Group B:<br>At the end of surgery, on the recovery room, this group will receive placebo (normal salin solution) for 90 minutes | Drug: Placebo<br>* At the end of surgery, they will continue receiving analgesia according the schedule.<br>* Other names: Multimodal analgesia will be performed with paracetamol 1 gr, dexketoprofen 50 mg and metamizol 2 gr and morphine according to visual analogue scale;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative morphine consumption | The visual analog scale (VAS) will be used to measure pain on recovery room and hospitalization area. | 48 hours |