Effect of Lidocaine Through Gastric Tube on PONV

Official title

Effect of Lidocaine Applied Via Nasogastric Tube on Postoperative Nausea and Vomiting in Obese Patients Undergoing Bariatric Surgery

Overview

The goal of this clinical trial is to learn if intragastric administration of lidocaine can reduce postoperative nausea and vomiting in obese patients undergoing laparoscopic sleeve gastrectomy. The main question it aims to answer is: Does administering 0.5% lidocaine via an orogastric tube reduce the incidence of postoperative nausea and vomiting (PONV) in the post-anesthesia care unit and within the first 24 hours after surgery compared to a placebo (normal saline)? Researchers will compare the Lidocaine Group to the Placebo Group to see if the intervention lowers the PONV incidence. Participants will: * Receive the assigned study solution (either 0.5% lidocaine 20ml or normal saline 20ml) through an orogastric tube upon surgery completion and before extubation. * Have their gastric tube clamped for 5 minutes to ensure mucosal exposure before removal. * Undergo standardized total intravenous anesthesia and perioperative management according to the study protocol. * Be assessed for nausea, vomiting, and other outcomes at specified time points postoperatively in the recovery room and at 6, 12, and 24 hours.

Detailed description

Postoperative nausea and vomiting (PONV) is a common complication following bariatric surgery, with incidence rates reaching up to 30-80%. In bariatric surgical patients, the burden of PONV is particularly high due to multiple risk factors, including surgical trauma to upper GI system, frequent opioid use, increased intra-abdominal pressure, altered gastric anatomy, and heightened sensitivity of gastrointestinal reflex pathways. Effective prevention and treatment of PONV in this population therefore represents a major clinical priority.

Current prophylactic strategies rely primarily on pharmacological agents such as serotonin (5-HT3) receptor antagonists, corticosteroids, dopamine antagonists, and multimodal combinations. Despite these measures, the incidence of breakthrough PONV remains significant, underscoring the need for additional safe, effective, and inexpensive interventions.

Lidocaine, traditionally used as a local anesthetic and antiarrhythmic, has gained attention in perioperative medicine for its systemic anti-inflammatory, analgesic, and opioid-sparing effects when administered intravenously. Evidence suggests that perioperative lidocaine can improve gastrointestinal motility, reduce visceral hypersensitivity, and facilitate earlier return of bowel function. These properties raise the possibility that lidocaine may also influence nausea and vomiting pathways by attenuating vagal afferent signaling, reducing local gastric irritation, and dampening inflammatory responses within the gastrointestinal mucosa.

Delivering lidocaine directly into the gastric cavity via an orogastric (OG) tube represents a novel and pragmatic approach. Unlike intravenous administration, intragastric instillation allows targeted mucosal exposure, potentially reducing afferent vagal stimulation that triggers nausea and vomiting. This method is technically simple, inexpensive, and feasible within the routine workflow of bariatric surgery, as OG tubes are already placed for intraoperative management.

This study aims to evaluate whether the administration of lidocaine via nasogastric tube can reduce the incidence of postoperative nausea and vomiting (PONV) in patients undergoing bariatric surgery. If effective, local lidocaine administration may serve as a simple, low-cost, and readily adoptable strategy to improve postoperative outcomes in bariatric surgery patients. This approach could expand the multimodal anesthesia regimen and optimize the enhanced recovery after surgery (ERAS) pathway for bariatric procedures.

Interventions

• Procedure Lidocaine
  Upon completion of the surgery and before extubation, 20 ml of 0.5% lidocaine should be administered through the pre - inserted orogastric tube. The gastric tube should be clamped for 5 minutes to ensure sufficient mucosal exposure, and then removed before extubation.
• Procedure Normal Saline (0.9% NaCl)
  Before extubation after the surgery is completed, administer 20 ml of normal saline through the pre - inserted orogastric tube. Clamp the gastric tube for 5 minutes to ensure sufficient mucosal exposure, and then remove the tube before extubation.

Primary outcome measures

• The incidence of postoperative nausea and vomiting (PONV) in the post - anesthesia care unit and within 24 hours after surgery. [Time frame: Within 24 hours after the operation]

Secondary outcome measures (5)

• Degree of postoperative nausea and vomiting [Time frame: 6 hours, 12 hours, and 24 hours after surgery]
• Incidence rates of simple vomiting, simple nausea, and their combination during the postoperative anesthesia recovery room period and within 24 hours after surgery. [Time frame: Within 24 hours after the operation]
• Use rescue antiemetics [Time frame: Within 24 hours after surgery.]
• Opioid use within 24 hours after surgery [Time frame: 24 hours after surgery]
• Time of first tolerable oral intake [Time frame: Within 72 hours after surgery.]

Eligibility criteria

Inclusion criteria

• Adults aged between 18 and 65 years old;
• American Society of Anesthesiologists (ASA) physical status classification II - III;
• Planned to undergo primary elective laparoscopic sleeve gastrectomy with general anesthesia;
• Capable of giving informed consent.

Exclusion criteria

• Known allergy, hypersensitivity or contraindication to lidocaine or amide - type local anesthetics;
• Previous significant liver or kidney dysfunction (e.g., ALT/AST > 3 times the upper limit of normal, GFR < 30 mL/min);
• History of epilepsy, cardiac conduction abnormalities or previous diagnosis of malignant hyperthermia;
• Pregnancy or lactation;
• Patients who received systemic lidocaine treatment during the operation;
• History of severe postoperative nausea and vomiting (PONV) or motion sickness, requiring multiple prophylactic medications;
• Emergency or revision bariatric surgery.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

China · 1 center

• General Hospital of Ningxia Medical University — Yinchuan

Identifiers

NCT: NCT07643298 · Siying He-2026-01

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗