This prospective, randomized controlled clinical trial aims to evaluate the effect of lateral neck cold application for vagal nerve stimulation on pain perception during peripheral venous cannulation in obese patients. Venous cannulation is a routine but painful procedure, especially in individuals with a body mass index (BMI) greater than 30, who often have heightened pain sensitivity due to chronic inflammation.
Participants will be randomly assigned to one of two groups:
Group 1 (Cold Application Group): A cold marble stone (0-4°C) will be applied to the lateral neck region (over the sternocleidomastoid muscle) for 5 seconds immediately before venous cannulation.
Group 2 (Control Group): Standard venous cannulation will be performed without any prior intervention.
Pain intensity will be assessed using the Visual Analog Scale (VAS) immediately after cannulation. Hemodynamic parameters (heart rate, blood pressure, oxygen saturation, respiratory rate) will be recorded before and after the procedure.
The primary outcome is the difference in VAS scores between the two groups. Secondary outcomes include changes in hemodynamic parameters. The study will enroll 150 participants over approximately two months following ethics approval.
Who can participate
Age range
18 Years – 72 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion Criteria:
* Adults aged 18-72 years
* physical status I-III
* Scheduled for elective surgery
* Body Mass Index (BMI) \> 30 kg/m²
* Provided written informed consent
Exclusion Criteria:
* Emergency surgical cases
* Oncologic surgery
* Pregnant patients
* History of hand dorsum surgery or scarring
* Psoriasis or other local skin lesions/infections at cannulation site
* Peripheral vascular disease
* Chronic analgesic, opioid, steroid, or gabapentinoid use
* Substance abuse history
* Peripheral neuropathy
* Previous or ongoing oncologic treatment
* Severe mental retardation or communication impairment preventing cooperation
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Venous cannulation pain (VAS, 0-10)
Timeframe: Immediately after cannulation (within ~1 minute)