Vitamin C on Acute and Chronic Post Mastectomy Pain

Study Overview
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Brief Summary
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This prospective randomized double-blinded controlled study will be conducted to evaluate the effect of perioperative vitamin C on acute and chronic post mastectomy pain after breast cancer surgery

Detailed Description
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There is cumulative evidence that postoperative pain is closely associated with subsequent persistent pain lasting months. The International Association for the Study of Pain has defined chronic postsurgical pain (CPSP) as a pain that develops after surgical intervention and persists at least 2 months.

Official Title
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Impact of Perioperative Vitamin C on Acute and Chronic Post Mastectomy Pain After Breast Cancer Surgery

Conditions
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Vitamin C, Post-mastectomy Pain Syndrome

Intervention / Treatment
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* Drug: vitamin C group
* Other: placebo group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Female patients aged ≥ 18years, with primary unilateral breast cancer and scheduled for lumpectomy, partial or total mastectomy with or without axillary lymph node dissection or modified radical mastectomy. Exclusion Criteria: - (1) Patients with renal stones or renal insufficiency, patients suffering from nausea and vomiting, gastroesophageal reflux or patients with chronic pain state. (2) Intake of analgesic within 24 hours before surgery. (3) Patients unable to comply with the study protocol for any reason. (4) Contraindications to paravertebral block (PVB) such as allergy to local anesthetics, infection, or coagulopathy.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vitamin C group<br>patients in this group will receive 2 gm vitamin C orally 1 hour before surgery and will receive 0.5 gm vitamin C per day orally for 50 days starting from the 2nd postoperative day. | Drug: vitamin C group<br>* patients in this group will receive 2 gm vitamin C orally 1 hour before surgery and will receive 0.5 gm vitamin C per day orally for 50 days starting from the 2nd postoperative day.<br>|
| Placebo Comparator: Placebo group<br>patients in this group will receive placebo tablets with the same manner.1 hour before surgery and for 50 days starting from the 2nd postoperative day. | Other: placebo group<br>* patients in this group will receive placebo tablets with the same manner; orally 1 hour before surgery and for 50 days starting from the 2nd postoperative day.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of chronic post mastectomy pain | Chronic pain will be assessed at 3, 6 months after surgery. Chronic pain will be defined as pain at the surgical site greater than or equal to 3 out of 10 on item 5 of the Brief Pain Inventory (item 5: Please rate your pain by circling the one number that best describes your pain on the average in the past 24h, no pain = 0, worst pain = 10) | 6 months after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The degree of acute postoperative pain | degree of acute postoperative pain scores in the 1st and 2nd postoperative days using visual analogue scale (VAS) in both groups. Postoperative pain using VAS scores: will be assessed at 1, 4, 6, 12, 18, 24, 30, 36, 42 and 48 hr. after surgery. 0: No pain, 10: the worst pain | 48 hours postoperative | 
| The amount of total opioid dose in 48 hours after surgery | Postoperative pain in the 1st and 2nd days will be assessed using VAS scores. If VAS score more than 3 morphine 0.05mg/kg will be given. | 48 hours postoperative | 
| The incidence of adverse effects | postoperative adverse effects like postoperative nausea and vomiting (PONV). | 48 hours postoperative |