Effect of intraperitoneal instillation versus subserosal infiltration of lidocaine on post-operative pain in laparoscopic cholecystectomy in a tertiary care hospital- A randomized controlled clinical trial

Introduction

The most commonly performed laparoscopic surgery is laparoscopic cholecystectomy. But, like all surgical interventions this ’very common’ procedure is associated with its own complications, the commonest one being postoperative pain. The main reason for staying overnight in the hospital on the day of surgery is pain. Different analgesic interventions have been investigated for their effect on early pain after laparoscopic cholecystectomy including patient controlled IV anesthesia, oral opioids, and opioid like pain killers, NSAIDs and intravenous corticosteroids. Although effective, they have systemic side effects. An ideal pain relief method has maximal local action and minimal systemic side effect. Local anesthetic drugs (LADs) are being used increasingly in the intra-operative period for pain management. Their application is not only limited to the skin incisions but can also be instilled into the peritoneal cavity and subserosa of Calot’s triangle to provide pain relief. Our study is an attempt to compare efficacy the intraperitoneal instillation of versus sub-serosal infiltration of Lignocaine in providing post-operative pain relief.

Research question

Which method of pre-emptive analgesia shows superior effectiveness in alleviating postoperative pain in patients undergoing laparoscopic cholecystectomy between subserosal infiltration and intraperitoneal instillation of 10 ml 1% lidocaine?

Research hypothesis

Null Hypothesis (H0): There is no difference in post operative pain in patients undergoing laparoscopic cholecystectomy by sub-serosal infiltration of 10 ml 1% lidocaine in comparison with  intra-peritoneal instillation of 10 ml 1% lidocaine.

Alternate Hypothesis (H1): Sub-serosal infiltration of 10 ml 1% lidocaine is different to intraperitoneal instillation of 10 ml 1% lidocaine in alleviating postoperative pain in patients undergoing laparoscopic cholecystectomy.

Aims and objectives

Primary objective:

To compare the difference in post-operative pain in patients undergoing laparoscopic cholecystectomy between pre-dissection sub-serosal infiltration of 10 ml 1% lidocaine and intra-peritoneal instillation of 10 ml 1% lidocaine.

Secondary objective:

1. To compare shoulder tip pain between the two groups

2. To compare post-operative nausea and vomiting between the two groups

3. Subgroup analysis of difference in outcome parameters between the two groups on the basis of:

a. Demographic and anthropometric factors

b. Comorbidities

c. Sonographic findings

Methodology

Selection criteria

All the patients who will undergo laparoscopic cholecystectomy between April and September will be invited to participate in the study. All the patients who consent to be part of the study will be included and randomized as stated above.

Inclusion Criteria:

1. Patients undergoing elective laparoscopic cholecystectomy between the age 18 years to 55 years.

Exclusion Criteria:

1. Jaundice

2. Pregnancy

3. Complicated morbid anatomy or very difficult dissection(Nassar scale III,IV,V)

4. Gall bladder malignancy

5. Any deviation from the proposed process of laparoscopy cholecystectomy, including conversion to open cholecystectomy

6. Equipment failure affecting duration of surgery

Standardization of procedure:

Patient included in the study after obtaining informed written consent shall be evaluated for as protocol including requisite pre-operative clinical evaluation and investigations. They shall be subjected to standard 3 o 4 port laparoscopic cholecystectomy. Supra umbilical 10mm port will be placed by Hasson’s open method and other ports were placed under peritoneoscopic visualization after CO2 insufflation to 12mmhg. After carrying out  general abdominal inspection gall bladder will be visualized. Traction will be applied over the gall bladder to identify the calot’s triangle. In group A, 10ml of 1% lidocaine (preservative free) shall be instilled slowly over the visceral peritoneum of Calot’s triangle slowly under direct visualization. In group B, a fine laparoscopic needle (20G) will be used to inject the 5ml of 1% lidocaine (preservative free) within the anterior serosa of Calot’s triangle after visually ascertaining that there is no puncture of vascular and ductal structures. The procedure will be repeated with 5ml of 1% lidocaine for posterior serosa of Calot’s triangle as well. In both groups there will be a elective wait of 5-6 minutes after drug delivery to allow the drug to be spread and fixed. Cholecystectomy shall be performed in standard technique and gall bladder shall be extracted through the umbilical port-site. 2% lidocaine port-site field block will be provided to all patients prior to dressing application. Standard intra-op and post-op analgesia will be provided to all patients. Post-op rescue analgesics will be given (diclofenac sodium 75mg) and its timing will be noted. Surgery shall performed by surgical consultants. A blinded observer shall be noting the post-operative VAS and vitals in the study proforma.

Data analysis:

Data will be analyzed using Microsoft excel and SPSS version 27. Graphical presentation of data shall be done whenever applicable. Appropriate techniques will be used for analysis. Numerical parameters will be compared by using student’s t test and/or ANOVA. Nominal data shall be compared using non-parameter test like chi-squared and Mann Whitney U test. Test continuous variables will be presented as mean and standard deviation, and categorical variables will be presented as frequency and precent. Cut-off p-value for significance shall be =<0.05 for all statistical tests.