Vitamin C Level Effect in Orthognathic Surgery

Study Overview
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Brief Summary
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Comparing the pre and post-operative blood plasma levels of vitamin C according to oxidative stress and investigate the correlation between post-operative analgesia requirement and vitamin C levels following orthognathic surgery.

Detailed Description
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Vitamin C (ascorbic acid) is a water-soluble vitamin that has many functions include antioxidant, neuroprotective, neuromodulator and co-factor for various enzymes or chemical reactions. Primarily ascorbic acid is the most potent non-enzymatic antioxidant agent in an extracellular fluid which is crucial for defense against oxidative stress. Recent clinical studies have shown that trauma or surgery may lead to oxidative stress and plasma vitamin C level decreases due to body demand that most likely caused by oxidative stress. Pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. One of the major purposes in the management of post-operative pain is to minimize the dose of medications to reduce side effects while providing adequate analgesia. In orthopedic surgery and management of postherpetic neuralgia oral vitamin C supplementation significantly reduced pain. However, the decrease in vitamin C concentration,the effects on antinociception and postoperative pain are not fully understood. In this study, investigators aimed to compare pre and post-operative blood plasma levels of vitamin C after orthognathic surgery and investigate a correlation between post-operative analgesia requirement and vitamin C levels without vitamin C administration.

Official Title
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Does Vitamin C Level Effect Postoperative Analgesia in Orthognathic Surgery: a Preliminary Study?

Conditions
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Maxillofacial Abnormalities, Maxillofacial Injuries, Maxillofacial Trauma

Intervention / Treatment
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* Other: Vitamin C


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiologists (ASA) classification I-II Scheduled for orthognatic surgery under general anesthesia Exclusion Criteria: history of bleeding diathesis, receiving anticoagulant treatment, known local anesthetics and opioid allergy, infection of the skin at the site of the needle puncture, pregnancy or lactation, patients who do not accept the procedure

Ages Eligible for Study
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Minimum Age: 19 Years
Maximum Age: 38 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Vitamin C|Pre and post-operative blood plasma levels of vitamin C will be investigated|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood plasma levels of vitamin C | Pre and post-operative blood plasma levels of vitamin C | Change from baseline blood plasma levels of vitamin C at postoperative 1, 2, 4, 8, 16 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Opioid consumption | Postoperative opioid consumption | Change from baseline opioid consumption levels at postoperative 1, 2, 4, 8, 16 hours |