In this study, after obtaining approval from the clinical research ethics committee (Health Sciences University Istanbul Kanuni Sultan Süleyman Training and Research Hospital, KAEK/2024.10.212), 51 patients aged 18-65 years who were treated with IV lidocaine and met the ACR (American College of Rheumatology) 2016 FM diagnostic criteria with accompanying sleep disturbance (Pittsburgh Sleep Quality Index score \>5) and persistent complaints despite pharmacological and non-pharmacological FM treatments (Numeric Rating Scala \>4) were retrospectively evaluated between June 2023 and June 2024 .. The study was conducted in accordance with the Declaration of Helsinki. Written informed consent was obtained from all patients in the study, which was conducted in a tertiary pain clinic in accordance with the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline. Patient information was recorded: age, gender, body mass index, duration of symptoms, antineuropathic medical treatments, side effects observed during treatment, and pre- and post-treatment scores from the Fibromyalgia Impact Questionnaire (FIQ) at 4 and 12 weeks, the NRS-11 (Numeric Rating Scale), the Short Form-12 (SF-12) subcomponents of the Mental Component Scale-12 (MBS-12) and Physical Component Scale-12 (FBS-12), and the Pittsburgh Sleep Quality Index (PSQI).
Procedure The patient was taken to the procedure room, monitored (5-lead electrocardiogram (ECG), pulse oximetry, and blood pressure), and intravenous access was established in the forearm. Before IV lidocaine was administered, a 12-lead ECG was obtained and evaluated for dysrhythmia by a cardiologist with at least 10 years of experience. The patients were informed about possible side effects such as dizziness, vertigo, nausea and vomiting, numbness of the tongue, palpitations, a metallic taste in the mouth, and dry mouth. Patients were administered a 120-minute IV lidocaine infusion with 500 cc of 0.9% saline solution under appropriate monitoring conditions. Patients were monitored for 2 hours after the infusion. Patients received 5 mg/kg IV lidocaine twice weekly, 3 days apart, in accordance with current literature. The patients' FIQ, NRS-11, SF-12, and PSQI scores were recorded before and after treatment, 4 and 12 weeks.
Assessment Scales The FIQ is a 10-item scale ranging from 0 to 100, with each question rated on a 0 to 10 scale. Higher scores indicate increased disease activity (11). The NRS-11 is an 11-point numerical scale that allows patients to rate their pain on a scale from 0 (no pain at all) to 10 (the most severe pain they have ever experienced) .
The SF-12 consists of 12 questions: two questions on physical role, two on physical functioning, one on bodily pain, one on general health, one on energy, one on social functioning, two on emotional role, and two on mental health. The subcomponents of the SF-12, the FQI-12 and MQI-12, both have scores ranging from 0 to 100, with higher scores representing better health .
The PSQI is an index in which patients self-report their sleep quality and disturbances over a 1-month period. This index, consisting of 19 questions and 7 subheadings, is scored on a scale of 0-21, with 0 being the best and 3 being the worst. Higher scores indicate worse sleep quality and disturbances .
