A Randomized Controlled Study for Evaluation of the Efficacy of Intraperitoneal Instillation of Ropivacaine with Dexmedetomidine Versus Ropivacaine with Ketamine for Post Operative Pain Relief Following Laparoscopic Cholecystectomy

**RATIONALE:**Intraperitoneal local anaesthetic instillation is a well established technique for pain relief in laparoscopic cholecystectomy with Bupivacaine being a commonly used drug in most of the studies. Ropivacaine has been used of late and with addition of adjuncts it provides adequate postoperative pain relief. Dexmedetomidine has been successfully used as an adjunct to ropivacaine for intraperitoneal instillation with prolonged duration of postoperative analgesia. Intraperitoneal Ketamine alone or with Bupivacaine has been found to have prolonged duration of analgesia. However, no study is available in literature which compares the efficacy of these two drugs as adjuncts to Ropivacaine for postoperative pain relief. Therefore, the present randomized double blinded controlled study is designed to compare the efficacy of intraperitoneal instillation of Ropivacaine with Dexmedetomidine versus Ropivacaine with Ketamine for postoperative pain relief following laparoscopic cholecystectomy.

AIM: To compare the efficacy of intraperitoneal instillation of Ropivacaine with Dexmedetomidine versus Ropivacaine with Ketamine for postoperative pain relief following laparoscopic cholecystectomy

OBJECTIVES

Primary Objective: To compare the time to demand of first dose of rescue analgesic between the three groups.

Secondary Objective:

To compare-

1.    Time to extubation.

2.    Hemodynamic parameters at the time of extubation

3.    Post-operative pain using Numeric Rating Scale (NRS).

4.    Total dose of rescue analgesia required in 24 hours

5.    Any adverse effects

6.    To assess the quality of post operative pain using Revised American Pain Society Patient Outcome Questionnaire.

MATERIALS AND METHODS

Place of study:

The study will be conducted in the Department of Anaesthesiology, Critical Care & Pain Medicine at University College of Medical Sciences and G.T.B Hospital, Shahdara, Delhi-95 after getting approval from the Institutional Ethics Committee-Human Research (IEC-HR). Informed written consent will be obtained from each patient willing to participate in the study.

Study design: A randomized double blinded controlled study

Duration of Study: Nov 2019 to April 2021

Blinding: Study drugs will be prepared by an independent anaesthesiologist and medication will be administered as per the group allocated. Both patient and observer will not be aware of the group or medication.

Participants: Total 60 patients, 20 in each group

Inclusion Criteria:

Patients having following criteria will be included in the study:

Patients of either gender giving consent for the study and aged 20-55 years belonging to ASA grade I or II scheduled for elective laparoscopic cholecystectomy under general anaesthesia.

Exclusion Criteria:

1.    Patients with cardiovascular, pulmonary, psychological or neurological diseases

2.    Patients who are known to be epileptic

3.    Patients who have an increase in intracranial tension

4.    Patients with known allergies to the study drugs

5.    Patients with abnormalities like heart block, left bundle branch block

6.    Patients in whom the procedure will be converted to open cholecystectomy

7.    Obese patients (BMI more than or equal to 30)

8. Patients in whom subhepatic drain is inserted after the removal of gall bladder.

  Allocation:

Sixty patients fulfilling the above mentioned selection criteria will be divided into the following two groups by a computer generated random number chart.

Group R (n=20)[Control group]: Each patient will receive 0.2% plain Ropivacaine in a total volume of 40 ml of instilled solution.

Group RD (n=20): Each patient will receive 0.7µg/kg Dexmedetomidine mixed with 0.2% Ropivacaine in a total volume of 40 ml of instilled solution.

Group RK (n=20): Each patient will receive 0.5 mg/kg Ketamine mixed with 0.2% Ropivacaine in a total volume of 40 ml of instilled solution.

Standard general anaesthesia will be given to every patient participating in the study and after surgery, time to demand of first dose of analgesia, total dose of rescue analgesia and hemodynamic parameters will be recorded. Any side effects during the post operative period will also be noted.

 OUTCOME MEASURES:

Primary outcome: Time to demand of first dose of rescue analgesia in the three groups

Secondary outcome: To compare in the three groups:

1.    Time to extubation.

2.    Hemodynamic parameters at the time of extubation

3.    Post-operative pain using Numeric Rating Scale (NRS).

4.    Total dose of rescue analgesia required in 24 hours

5.    Any adverse effects

6.    To assess the quality of post operative pain using Revised American Pain Society Patient Outcome Questionnaire.

 STATISTICAL ANALYSIS:

One time quantitative measurements will be compared by one way ANOVA followed by Tukey’s test and repeatedly measured by repeated measure ANOVA followed by Dunnett’s test. Qualitative parameters will be compared by Chi-square test. p value of < 0.05 will be considered as significant. This analysis will be carried out in SPSS 20.0.