Comparing Analgesic Efficacy of Systemic Lidocaine Against Placebo in General Anesthesia in Bariatric Surgery

Miodrag Filipovic, Prof. Dr. med.140 enrolled

Overview

The investigators plan to evaluate the analgesic effect of systemic Lidocaine in addition to general anesthesia during bariatric surgery. Patients will be subdivided into a "Lidocaine group" and a "Control group". The primary outcome will be the proportion of patients suffering from higher pain intensity within the first four hours after bariatric surgery. Secondary outcomes include the average maximal pain intensity during first four hours and during 48 hours, total opiate consumption, occurence of postoperative nausea and vomiting, time to first defecation and total time spent in hospital.

Postoperative pain is a common problem in today's surgery, although pain management techniques have improved in the last years. Systemic application of lidocaine has gained interest since several studies have shown its analgesic, anti-inflammatory and antihyperalgesic properties. In this clinical trial the analgesic effect of intravenously administrated lidocaine is compared with placebo. Despite longstanding use as an antiarrhythmic agent and its use in many clinical trial as analgesic, lidocaine is not licensed for this indication and application. Current studies, setting the focus on abdominal surgery, indicated that the systemic application of lidocaine was associated with fewer intensity of pain at rest and during mobilization and resulted in a decrease of patients'opiate consumption. The intervention to be studied will either be the additional application of systemic lidocaine 1% to general anesthesia in bariatric surgery or the application of placebo. Patients, randomly assigned to one study group, will be surveyed for 48 hours after completion of surgery, experienced pain, occurrence of PONV, time to first defecation and length of hospitalization will be monitored. The population to be studied will include 140 patients listed for bariatric surgery at the Kantonsspital St. Gallen. Patients, medical practitioner, nurses and investigators will be blinded. Each patient will self-evaluate his maximal experienced pain eight-hourly during a sequence of 48 hours after completion of surgery.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Interventions

Lidocaine HydrochlorideDRUG

The intervention to be studied will be the additional application of systemic lidocaine 1% dosed 1.5 ml/kg LBM to general anesthesia in bariatric surgery. Patients, randomly assigned to one study group, will be surveyed for 48 hours after completion of surgery, experienced pain, occurrence of PONV, time to first defecation and length of hospitalization will be monitored. Patients, medical practitioner, nurses and investigators will be blinded by utilization of equal appearance and packing of IMPs, which will be fabricated individually for each patient and on request one to two days before surgery by the pharmacy. Each patient will self-evaluate his maximal experienced pain eight-hourly during a sequence of 48 hours after completion of surgery.

Saline SolutionDRUG

The intervention to be studied will be the additional application of NaCl 0.9% dosed 1.5 ml/kg LBM to general anesthesia in bariatric surgery as a placebo. Patients, randomly assigned to one study group, will be surveyed for 48 hours after completion of surgery, experienced pain, occurrence of PONV, time to first defecation and length of hospitalization will be monitored. Each patient will self-evaluate his maximal experienced pain eight-hourly during a sequence of 48 hours after completion of surgery.

Outcomes

Primary Outcomes

Postoperative VAS/NRS Score

Any development of VAS/NRS score \> 3 (Visual Analog Scale/Numeric Rating Scale ranging from minimum 0 to maximum 10 points, with 0 points as "no pain" to 10 points as "severe pain") , in hourly measurements within the first four hours after completion of bariatric surgery to evaluate the pain experienced by patients after the surgical intervention

Time frame: 0 - 4 hours after surgery

Secondary Outcomes

Average experienced maximal pain during the first four hours and 48 hours after Surgery

Average experienced maximal pain during the first four hours and 48 hours (in hourly measurements on post anesthesia care unit (PACU) and in eight-hourly measurements on surgical ward) is assessed by VAS/NRS score (Visual Analog Scale/Numeric Rating Scale ranging from minimum 0 to maximum 10 points, with 0 points as "no pain" to 10 points as "severe pain").