Thyroidectomy, Oxidative Stress, Anesthesia
Conditions
Keywords
Opioid-free anesthesia, Opioid-based anesthesia, Thyroid surgery, Total antioxidant status, Thiol-disulfide homeostasis
Brief summary
This study will compare opioid-free anesthesia and opioid-based anesthesia in adult euthyroid patients undergoing elective thyroidectomy. Opioid-based anesthesia is commonly used during surgery, but opioids may be associated with adverse effects such as nausea, vomiting, respiratory depression, hyperalgesia, and increased postoperative opioid use. Opioid-free anesthesia uses non-opioid medications as part of a multimodal strategy to provide intraoperative analgesia. The main aim of this prospective randomized study is to evaluate whether opioid-free anesthesia changes the perioperative oxidative stress response compared with opioid-based anesthesia. Oxidative stress will be assessed using serum biomarkers, including native thiol, total thiol, disulfide, total antioxidant status, total oxidant status, and oxidative stress index. Eligible patients will be randomly assigned to receive either opioid-free anesthesia or fentanyl-based opioid anesthesia. Blood samples will be collected before anesthesia induction, 30 minutes after extubation, and 24 hours after surgery. The study will also compare postoperative pain scores, rescue analgesic requirement, postoperative nausea and vomiting, recovery characteristics, and intraoperative hemodynamic variables between the two anesthesia strategies.
Detailed description
This is a single-center, prospective, randomized, parallel-group clinical study. Adult euthyroid patients scheduled for elective thyroidectomy will be randomized in a 1:1 ratio to opioid-free anesthesia or opioid-based anesthesia. The opioid-based group will receive fentanyl-based intraoperative analgesia. The opioid-free group will receive multimodal non-opioid analgesia with dexmedetomidine and lidocaine. General anesthesia will otherwise be standardized, including propofol-based total intravenous anesthesia, neuromuscular blockade, antiemetic prophylaxis, and postoperative non-opioid analgesia. The primary focus of the study is the perioperative oxidative stress response. Venous blood samples will be collected at three time points: before anesthesia induction, 30±10 minutes after extubation in the post-anesthesia care unit, and 24±2 hours after surgery. Serum native thiol, total thiol, disulfide, total antioxidant status, and total oxidant status will be measured, and oxidative stress index will be calculated from total oxidant status and total antioxidant status. Secondary clinical outcomes will include postoperative pain intensity, rescue opioid consumption, postoperative nausea and vomiting, recovery characteristics, and intraoperative hemodynamic stability.
Interventions
DRUGFentanyl (IV)
Fentanyl-based intraoperative analgesia consisting of fentanyl 1-2 mcg/kg intravenously at induction followed by fentanyl infusion at 1-2 mcg/kg/hour during surgery. No additional fentanyl bolus will be administered, and the total intraoperative fentanyl dose will not exceed 5 mcg/kg.
Dexmedetomidine will be administered intravenously at 0.4-0.7 mcg/kg/hour without a loading dose. The infusion will be discontinued 10-15 minutes before the end of surgery. Intravenous lidocaine will be administered as a 1-1.5 mg/kg bolus followed by a continuous infusion of 1-2 mg/kg/hour during surgery. The lidocaine infusion will be discontinued at the end of surgery.
Sponsors
Malatya Egitim Ve Arastirma Hastanesi
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Intervention model description
Participants will be prospectively enrolled into one of two groups according to the anesthesia strategy selected by the attending anesthesiologist based on routine clinical assessment and patient characteristics. No random allocation will be performed. Both groups will undergo elective thyroidectomy under standardized propofol-based total intravenous general anesthesia. The opioid-free anesthesia group will receive multimodal non-opioid intraoperative analgesia with dexmedetomidine and intravenous lidocaine, while the opioid-based anesthesia group will receive fentanyl-based intraoperative analgesia.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Adult patients aged 18 to 65 years * Scheduled for elective thyroidectomy * American Society of Anesthesiologists physical status I-II * Euthyroid status, defined as thyroid-stimulating hormone, free thyroxine, and free triiodothyronine levels within the reference range * Able to understand the study procedures and provide written informed consent
Exclusion criteria
* Uncontrolled advanced systemic disease, including advanced cardiac, pulmonary, renal, or hepatic failure * Active infection * Use of high-dose antioxidant supplementation within the last month * Widespread inflammation related to malignancy * Known severe allergy or contraindication to any study medication * Refusal to participate in the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Oxidative Stress Index From Preoperative Baseline to 24 Hours After Surgery | Preoperative baseline before anesthesia induction and 24 hours after surgery (±2 hours) | Oxidative Stress Index (OSI) will be calculated from serum total oxidant status (TOS) and total antioxidant status (TAS). The primary outcome will be the change in OSI from the preoperative baseline measurement to the measurement obtained 24 hours after surgery. The change in OSI will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Total Antioxidant Status (TAS) | Preoperative baseline before anesthesia induction and 24 hours after surgery (±2 hours) | Serum total antioxidant status (TAS) will be measured to assess systemic antioxidant capacity. The change in TAS from preoperative baseline to 24 hours after surgery will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Change in Total Oxidant Status (TOS) | Preoperative baseline before anesthesia induction and 24 hours after surgery (±2 hours) | Serum total oxidant status (TOS) will be measured to assess systemic oxidant burden. The change in TOS from preoperative baseline to 24 hours after surgery will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Change in Native Thiol Level | Preoperative baseline before anesthesia induction and 24 hours after surgery (±2 hours) | Serum native thiol levels will be measured as a component of thiol-disulfide homeostasis. The change in native thiol level from preoperative baseline to 24 hours after surgery will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Change in Total Thiol Level | Preoperative baseline before anesthesia induction and 24 hours after surgery (±2 hours) | Serum total thiol levels will be measured as a component of thiol-disulfide homeostasis. The change in total thiol level from preoperative baseline to 24 hours after surgery will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Change in Disulfide Level | Preoperative baseline before anesthesia induction and 24 hours after surgery (±2 hours) | Serum disulfide levels will be calculated as a component of thiol-disulfide homeostasis. The change in disulfide level from preoperative baseline to 24 hours after surgery will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Postoperative Pain Intensity Assessed Using the Visual Analog Scale (VAS) | During the first 24 hours after surgery | Postoperative pain intensity will be assessed using the Visual Analog Scale (VAS), ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. VAS scores will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Total Rescue Opioid Consumption Within 24 Hours After Surgery | From the end of surgery to 24 hours after surgery | Total rescue opioid consumption during the first 24 hours after surgery will be recorded for each participant and compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Incidence of Postoperative Nausea and Vomiting (PONV) | From the end of surgery to 24 hours after surgery | The occurrence of postoperative nausea and/or vomiting (PONV) during the first 24 hours after surgery will be recorded for each participant. The incidence of PONV will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
| Intraoperative Hemodynamic Parameters | From induction of anesthesia to the end of surgery | Intraoperative hemodynamic parameters will be assessed using mean arterial pressure (MAP, mmHg) and heart rate (beats per minute), recorded at predefined time points during anesthesia. Changes in these parameters over the intraoperative period will be compared between the opioid-free anesthesia and opioid-based anesthesia groups. |
Countries
Turkey (Türkiye)
Contacts
CONTACTLeman Acun Delen, Associate Professor
Outcome results
None listed