Non-Invasive Vagus Nerve Stimulation in Burn Patients During Dressing

Burn injuries are associated with severe pain, psychological distress, and reduced quality of life. Dressing procedures may cause additional procedural pain and anxiety, which can negatively affect patient comfort, treatment adherence, and rehabilitation. Non-invasive vagus nerve stimulation is a neuromodulation method that stimulates the auricular branch of the vagus nerve through electrodes placed on the external ear. This method may modulate autonomic nervous system activity and may have beneficial effects on pain and anxiety.

This randomized, three-group comparative interventional study will include adult burn patients who require repeated dressing procedures. A total of 96 participants will be included, with 32 participants in each group. Participants will be randomly assigned to one of three groups: non-invasive vagus nerve stimulation before dressing, non-invasive vagus nerve stimulation during dressing, or standard dressing care only.

In the first intervention group, non-invasive vagus nerve stimulation will be applied for 20 minutes before the dressing procedure. In the second intervention group, non-invasive vagus nerve stimulation will be applied for 20 minutes during the dressing procedure. In the control group, participants will receive only the standard dressing procedure without non-invasive vagus nerve stimulation.

For participants receiving non-invasive vagus nerve stimulation, electrodes will be placed on the tragus and the inner and posterior surfaces of the concha of the external ear. Stimulation will be applied continuously for 20 minutes using a biphasic asymmetric waveform, a pulse duration of 300 microseconds, and a frequency of 25 Hz. The stimulation intensity will be increased in 0.1 mA steps until the sensory threshold is reached. If the participant feels unwell during stimulation, the procedure will be stopped.

Participants are expected to undergo dressing procedures every other day for a total of seven sessions. Pain will be evaluated using the Visual Analog Scale before and after each dressing session. Anxiety will be evaluated using the Beck Anxiety Inventory, and quality of life will be evaluated using the SF-12 Health Survey before the first dressing session and before the seventh dressing session. The study will compare changes in pain, anxiety, and quality of life between the three groups.

Inclusion criteria

• Aged 18 to 65 years
• Having superficial or deep second-degree burns requiring dressing during the acute period
• Expected to attend at least 7 dressing sessions
• Willing to participate in the study and able to provide written informed consent
• Able to read and understand Turkish

Exclusion criteria

• Infection, ulcer, or scar tissue on the auricle
• Burns in the head and neck region that prevent application of the device to the auricular vagus nerve area
• Metallic implant in the skull
• Excessive sensitivity, injury, or inflammation in the ear
• Chronic pulmonary and/or cardiac disease
• Heart rate below 60 beats per minute
• Presence of a pacemaker or cochlear implant
• Uncontrolled hypertension
• Lack of cooperation
• Refusal or inability to sign the informed consent form