Intraperitoneal Dexmedetomidine Versus Ketamine With Bupivacaine For Postoperative Analgesia

Post-laparoscopic sleeve pain management is essential for early mobilization of the patient and so on decrease post-operative complication. The use of opioids is associated with adverse effects such as nausea, pruritus, sedation, and occasionally respiratory depression.

Previous studies stated that intraperitoneal instillation of bupivacaine alone has been used to reduce acute postoperative abdominal and shoulder pain allow early mobilization and decrease postoperative opioid requirements and its complications.

In this study the investigators will compare between intraperitoneal instillation of dexmedetomidine with bupivacaine versus ketamine with bupivacaine in patients undergoing laparoscopic sleeve gastrectomy under general anesthesia regarding to postoperative pain relief to reduce morbidity and mortality.

Obesity is a serious condition in developed and developing countries occur due to some hormonal disorder or due to reduce energy expenditure with increasing energy uptake \[1\]. Nowadays, obesity considered the second cause of deaths after smoking all over the world \[2\].

Severe obesity increase the incidence of many chronic disease such as (diabetes mellitus, hypertension, cardiovascular diseases and others) \[3\]. This leads to substantial morbidity, early mortality \[4\], impaired quality of life \[5\] and excess healthcare expenditures \[6\].

Laparoscopic bariatric surgery is the most recommended and effective long-term treatment for morbid obesity (which body mass index (BMI) ≥40 kg/m2) and obesity-related complication \[7\].

Postoperative pain management after laparoscopic sleeve still considers a major challenge. As many of the patients express moderate-to-severe pain in postoperative period \[8\]. Causes of postoperative pain include inflammation of the peritoneum, intra-abdominal cavity stretch and irritation of diaphragm by carbon-dioxide (CO2) remains in the abdominal cavity \[9\].

Multimodal analgesia regimens such as parenteral opioids, nonsteroidal anti-inflammatory drugs and intraperitoneal instillation of different drugs such as local anesthetic drugs alone or with adjuvants like; opioid and α2 agonists' drugs such as clonidine and dexmedetomidine have been tried to reduce overall pain and postoperative complications of patients undergoing laparoscopic surgeries \[8, 9\].

Bupivacaine is the most commonly used local anesthetic drug, its intraperitoneal instillation has become a popular practice for pain relief after laparoscopic surgery as it causes blockade of free afferent nerve endings in peritoneum \[10\].

Dexmedetomidine, the pharmacologically active d-isomer of medetomidine, it is a potent and highly selective α2-adrenoreceptor agonist with sympatholytic, sedative, amnestic, anxiolytic, neuroprotective and analgesic properties \[11\].

Ketamine is an immunomodulatory agent and anti-inflammatory drug and it has a noncompetitive antagonist of the N-methyl-d-aspartate (NMDA) receptor that blocks nociceptive input and reduce hyperalgesia \[12\].

Eligibility Criteria:
Inclusion Criteria:

* Patient acceptance.
* Age 21-60 years old.
* Sex both male and female.
* BMI ≥40 kg/m2
* ASA II and ASA III.
* Scheduled for elective laparoscopic sleeve gastrectomy under general anesthesia.

Exclusion Criteria:

* Patients with known history of allergy to study drugs.
* Patients with uncontrolled diabetes mellitus.
* Psychological and mental disorders.
* Severe hypertensive, cardiac, hepatic and renal patients.
* Patients on opioid or sedative use.