Effect of Intravenous High Dose Vitamin C on Postoperative Pain and Morphine Use after Laparoscopic Colectomy: A Randomized Controlled Trial

Efficacy of Vitamin C as Glucocorticoid Substitute for Reducing Pain and Inflammation After Total Hip Arthroplasty: A Randomized Controlled Trial

BACKGROUND

Vitamin C shows strong anti-inflammatory and analgesic effects, so we explored whether it can replace glucocorticoids in reducing pain and inflammation after total hip arthroplasty (THA).

METHODS

In this prospective trial, a consecutive series of 107 patients (43.0% men, 56.8 ± 10.1 years of age, 100% Han Chinese) who underwent THA due to end-stage hip disease at our medical center between January 2023 and January 2024 were randomized to receive vitamin C, dexamethasone, or neither dexamethasone nor vitamin C after surgery. The 3 groups were compared in terms of the primary outcomes of pain reported on a visual analogue scale (VAS), perioperative morphine use, and blood indices of inflammation and fibrinolysis as well as in terms of secondary outcomes of efficacy and safety.

RESULTS

Compared with patients in the control group, those who received vitamin C or dexamethasone reported a significantly lower VAS pain score on postoperative day 1, had significantly lower perioperative morphine consumption, and demonstrated significantly lower blood levels of C-reactive protein on days 1 and 2. The 2 groups also showed a significantly lower rate of rescue analgesia on postoperative day 1 and significantly higher Harris hip scores of joint function at 2 and 12 weeks after surgery, as well as significantly smaller thigh circumference and a lower rate of swelling on the first 2 days after surgery. Either treatment was associated with a significantly lower rate of postoperative nausea and vomiting. Dexamethasone was associated with greater blood glucose levels after surgery.

CONCLUSIONS

Vitamin C may be an effective substitute for glucocorticoids for reducing morphine use and the risk of nausea or vomiting and for improving joint function after THA without side effects causing blood glucose fluctuations.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

High-dose vitamin C as a metabolic treatment of cancer: a new dimension in the era of adjuvant and intensive therapy

The anti-cancer mechanism of High-dose Vitamin C (HDVC) is mainly to participate in the Fenton reaction, hydroxylation reaction, and epigenetic modification, which leads to the energy crisis, metabolic collapse, and severe peroxidation stress that results in the proliferation inhibition or death of cancer cells. However, the mainstream view is that HDVC does not significantly improve cancer treatment outcomes. In clinical work and scientific research, we found that some drugs or therapies can significantly improve the anti-cancer effects of HDVC, such as PD-1 inhibitors that can increase the anti-cancer effects of cancerous HDVC by nearly three times. Here, the adjuvant and intensive therapy and synergistic mechanisms including HDVC combined application of chemoradiotherapies multi-vitamins, targeted drugs, immunotherapies, and oncolytic virus are discussed in detail. Adjuvant and intensive therapy of HDVC can significantly improve the therapeutic effect of HDVC in the metabolic treatment of cancer, but more clinical evidence is needed to support its clinical application.

The Use of High-Dose Intravenous L-Ascorbate in Pain Therapy: Current Evidence from the Literature

INTRODUCTION

Pain is the most common reason for seeking medical treatment. Despite extensive research efforts and effective analgesics modulating pain, there is still a major therapeutic gap in addressing the root causes of pain. Pain is associated with tissue damage induced by oxidative stress and induction of inflammatory mediators following high consumption of antioxidants. The role of antioxidants in general, and the administration of L-ascorbate in particular, is still controversially discussed and underestimated in the daily clinical practice.

METHODS

The current literature on the therapeutic effect of L-ascorbate, ascorbic acid, and vitamin C on various pain conditions was evaluated against the background of evidence-based medicine. Those articles, obtained from systematic search in PubMed, were critically assessed and rated in terms of evidence level and methodological quality by two independent experts. The primary purpose of this work was to establish specific pain therapy guidance for intravenous L-ascorbate.

RESULTS

A PubMed search revealed 14 suitable articles comprising controlled clinical trials and meta-analyses. An additional ten publications could be identified via secondary literature. There is supporting evidence for the efficacy of ascorbate treatment in inflammatory pain conditions, in the complex regional pain syndrome, in post zoster neuralgia, in neuropathic pain, in post-operative pain conditions, and in tumor-related pain. However, the considered studies differ in the type of administration, in dosage, in duration of treatment, as well as in quality of research. Despite all study heterogeneity, it became evident that research of high scientific quality is in support of the efficacy of L-ascorbate in pain treatment.

DISCUSSION

Oxidative stress is present in almost all pain conditions. Because oral administration of most magistral formulas of vitamin C does not provide biological availability, parenteral administration should be preferred and can be supported by an oral dose with high bioavailability on days without intravenous treatment. L-ascorbate should be preferred for parenteral high dosage, rather than ascorbic acid, as it does not release acid valences under physiological conditions.

CONCLUSIONS

L-ascorbate is an effective, safe, and economically favorable integrative treatment option for various pain conditions, addressing the root cause of tissue damage and inflammatory mediator burst.

Vitamin C and catheter-related bladder discomfort after transurethral resection of bladder tumor: A double-blind, randomized, placebo-controlled study

STUDY OBJECTIVE

We evaluated the effect of vitamin C administration on postoperative catheter-related bladder discomfort (CRBD).

DESIGN

A double-blind, randomized controlled trial.

SETTING

University tertiary hospital.

PATIENTS

The participants were patients undergoing transurethral resection of bladder tumor.

INTERVENTION

Patients were randomly assigned to either vitamin C (n = 59) or control (n = 59). The vitamin C group received 1 g of vitamin C intravenously and the control group received normal saline, administered after the induction of anesthesia.

MEASUREMENTS

The primary endpoint was moderate or greater CRBD immediately postoperatively. Secondary outcomes included the incidence of moderate or greater CRBD at 1, 2, and 6 h postoperatively. The symptom of CRBD is either a burning sensation with an urge to void or discomfort in the suprapubic area. Moderate CRBD was defined as spontaneously reported by the patient without any behavioral responses, such as attempts to remove the urinary catheter, intense verbal reactions, and flailing limbs. Severe CRBD was spontaneously reported by the patient with behavioral responses. Patient satisfaction scores were also evaluated.

MAIN RESULTS

The group that received vitamin C exhibited a significantly lower incidence of moderate or greater CRBD immediately postoperatively compared with the control group (17 [28.8%] vs. 40 [67.8%], p < 0.001, relative risk [95% confidence interval] = 0.426 [0.274-0.656]). The vitamin C group also showed a significantly lower incidence of moderate or greater CRBD at 1 and 2 h postoperatively compared with the control group (10 [16.9%] vs. 25 [42.4%], p = 0.003; and 5 [8.5%] vs. 16 [27.1%], p = 0.008, respectively). However, there was no significant difference in the incidence of moderate or greater CRBD 6 h postoperatively. Patient satisfaction scores were significantly higher in the vitamin C group than in the control group (5.0 ± 1.3 vs. 4.4 ± 1.4, p = 0.009).

CONCLUSIONS

Patients who received vitamin C had decreased CRBD and improved patient satisfaction following transurethral resection of bladder tumor.

Anti-Inflammatory Effect of Vitamin C during the Postoperative Period in Patients Subjected to Total Knee Arthroplasty: A Randomized Controlled Trial

Vitamin C, a potent reducing and antioxidant agent, plays an important role in the body, aiding in the growth of cartilage and bones. It is also involved in mechanisms that help reduce inflammation and its effects on the body. In addition, vitamin C decreases pro-inflammatory cytokines, such as IL-6, which produce acute-phase proteins such as CRP and influence inflammatory markers such as ESR. We carried out a study with 110 patients who underwent total knee replacement surgery. We divided the patients into two groups, in which the intervention group received 15 g of parenteral vitamin C during the immediate postoperative period while the control group did not. Patients who received 15 g of vitamin C after total knee replacement surgery had decreased inflammatory markers, specifically CRP and ESR. Overall, administering vitamin C in the post-surgical period results in improved management of inflammation, as evidenced by a decrease in CRP and ESR values. This leads to faster recovery and better healing outcomes for patients undergoing total knee replacement surgery. Furthermore, the beneficial effects of vitamin C in reducing proinflammatory cytokines, reducing the need for opioid analgesics, and its mild adverse effects make it a promising adjuvant in managing postoperative recovery.

Nutrient Therapy for the Improvement of Fatigue Symptoms

Fatigue, characterised by lack of energy, mental exhaustion and poor muscle endurance which do not recover following a period of rest, is a common characteristic symptom of several conditions and negatively impacts the quality of life of those affected. Fatigue is often a symptom of concern for people suffering from conditions such as fibromyalgia, chronic fatigue syndrome, cancer, and multiple sclerosis. Vitamins and minerals, playing essential roles in a variety of basic metabolic pathways that support fundamental cellular functions, may be important in mitigating physical and mental fatigue. Several studies have examined the potential benefits of nutrients on fatigue in various populations. The current review aimed to gather the existing literature exploring different nutrients' effects on fatigue. From the searches of the literature conducted in PubMed, Ovid, Web of Science, and Google scholar, 60 articles met the inclusion criteria and were included in the review. Among the included studies, 50 showed significant beneficial effects (p < 0.05) of vitamin and mineral supplementation on fatigue. Altogether, the included studies investigated oral or parenteral administration of nutrients including Coenzyme Q10, L-carnitine, zinc, methionine, nicotinamide adenine dinucleotide (NAD), and vitamins C, D and B. In conclusion, the results of the literature review suggest that these nutrients have potentially significant benefits in reducing fatigue in healthy individuals as well as those with chronic illness, both when taken orally and parenterally. Further studies should explore these novel therapies, both as adjunctive treatments and as sole interventions.

Does the vitamin C level affect postoperative analgesia in patients who undergo orthognathic surgery?

Vitamin C has a critical role in pain management because of its antioxidative, neuroprotective, and anti-nociceptive properties. Oxidative stress caused by surgery increases the requirement for vitamin C. The aim of this study was to evaluate the change in vitamin C level and its effect on postoperative pain in patients undergoing orthognathic surgery. Thirty patients were included in the study. The relationships between the postoperative plasma vitamin C level, duration of surgery, postoperative analgesic consumption, and pain scores (visual analogue scale) were analysed. The difference between the mean pre- and postoperative vitamin C levels was found to be statistically significant (7.5 ± 2.9 mg/l vs 4.9 ± 2.3 mg/l, respectively; P = 0.001). There was no significant relationship between the duration of surgery and the vitamin C level decrease (P > 0.05). There was an inverse correlation between the postoperative vitamin C level and the amount of analgesic requested via patient-controlled analgesia (r = -0.699, P < 0.001). The findings suggest that, in patients who undergo orthognathic surgery, plasma vitamin C levels decrease significantly (34.6%), and an increase in the duration of surgery is not associated with any decrease in the vitamin C levels. A low postoperative plasma vitamin C level was found to be associated with greater postoperative analgesic consumption. In patients with preoperative plasma vitamin C levels ≤ 42 µmol/l, perioperative vitamin C administration may be considered for postoperative pain management.

Effect of Immature Rubus occidentalis on Postoperative Pain in a Rat Model

Background and Objectives: This study aimed to identify the analgesic properties of immature Rubus occidentalis extract (iROE) using a postoperative-pain rat model. We also aimed to compare the analgesic effects of iROE to those of mature R. occidentalis extract (mROE) and examine the proinflammatory cytokine response and associated underlying mechanisms. Materials and Methods: In adult male Sprague Dawley rats, acute postoperative pain was induced through plantar hind-paw incisions. After the plantar incisions were made, the rats were intraperitoneally administered with normal saline or various doses of iROE and mROE to investigate and compare the analgesic effects of iROE and mROE. The mechanisms underlying iROE-induced analgesia were investigated via post-incisional administration of yohimbine, dexmedetomidine, prazosin, naloxone, atropine, or mecamylamine, followed by iROE. Mechanical withdrawal threshold (MWT) evaluations with von Frey filaments were carried out at different time points. Serum levels of tumor necrosis factor α, interleukin (IL)-1β, and IL-6 were measured to assess inflammatory responses. Multivariate analysis of variance (MANOVA) and linear mixed-effects model (LMEM) analysis were used to analyze the analgesic effect data. Results: The MWTs demonstrated significant increases in iROE in a dose-dependent manner up to 2 h after the plantar incisions were made. An LMEM analysis demonstrated that iROE yielded a significantly greater analgesic effect than mROE, but there was no significant difference between the two according to MANOVA. Dexmedetomidine enhanced the MWT-confirmed iROE response, while yohimbine and naloxone diminished it. Administration of iROE significantly attenuated the post-incisional increases in serum IL-1β and IL-6 levels. Conclusions: The iROE demonstrated analgesic and anti-inflammatory effects in a rat model of incisional pain, which were more pronounced than those associated with mROE. The analgesic activity of iROE may be associated with α₂-adrenergic and opioid receptors.

[Essential trace elements, vitamins, and selected electrolytes in complementary medicine for cancer patients]

OBJECTIVE

Are there any evidence-based medicine (EBM)-supported treatment approaches of complementary and alternative medicine (CAM) methods for urological oncologists?

METHODS

We reviewed the actual German S3 guidelines "Supportive Care" and "Complementary Medicine" as well as the online-tool Onkopedia for recommendations about essential trace elements (Zn, Se, Mn, Fe), vitamins (A, B, C, D, E), and electrolytes (Mg, Ca). Furthermore, we added results of randomized trials to present potential future developments.

RESULTS

Each therapy with micronutrients should be based on laboratory observation of a deficit. There are selected guideline recommendations for selenium, iron and vitamin D. Potential indications were registered for manganese, vitamin A derivates, and vitamin C. No benefit was observed for vitamin B, zinc, and vitamin E.

CONCLUSION

Micronutrients should be substituted in the case of deficit. General supplementation of daily nutrition is not recommended for cancer patients.

Investigating Causal Associations of Diet-Derived Circulating Antioxidants with the Risk of Digestive System Cancers: A Mendelian Randomization Study

Molecular mechanisms and observational studies have found that diet-derived antioxidants are associated with digestive system cancers, whereas there is a lack of causal evidence from randomized clinical trials. In this study, we aimed to assess the causality of these associations through a Mendelian randomization (MR) study. Single nucleotide polymorphisms of diet-derived circulating antioxidants (i.e., α- and γ-tocopherol, ascorbate, retinol, β-carotene, lycopene, and urate), accessed by absolute levels and relative metabolite concentrations, were used as genetic instruments. Summary statistics for digestive system cancers were obtained from the UK Biobank and FinnGen studies. Two-sample MR analyses were performed in each of the two outcome databases, followed by a meta-analysis. The inverse-variance weighted MR was adopted as the primary analysis. Five additional MR methods (likelihood-based MR, MR-Egger, weighted median, penalized weighted median, and MR-PRESSO) and replicate MR analyses for outcomes from different sources were used as sensitivity analyses. Genetically determined antioxidants were not significantly associated with five digestive system cancers, after correcting for multiple tests. However, we found suggestive evidence that absolute ascorbate levels were negatively associated with colon cancer in UK Biobank-the odds ratio (OR) per unit increase in ascorbate was 0.774 (95% confidence interval [CI] 0.608-0.985, p = 0.037), which was consistent with the results in FinnGen, and the combined OR was 0.764 (95% CI 0.623-0.936, p = 0.010). Likewise, higher absolute retinol levels suggestively reduced the pancreatic cancer risk in FinnGen-the OR per 10% unit increase in ln-transformed retinol was 0.705 (95% CI 0.529-0.940, p = 0.017), which was consistent with the results in UK Biobank and the combined OR was 0.747 (95% CI, 0.584-0.955, p = 0.020). Sensitivity analyses verified the above suggestive evidence. Our findings suggest that higher levels of antioxidants are unlikely to be a causal protective factor for most digestive system cancers, except for the suggestive protective effects of ascorbate on colon cancer and of retinol on pancreatic cancer.

The Influence of Dietary Supplementations on Neuropathic Pain

Neuropathic pain is defined as pain caused by a lesion or disease of the somatosensory nervous system and affects 7-10% of the worldwide population. Neuropathic pain can be induced by the use of drugs, including taxanes, thus triggering chemotherapy-induced neuropathic pain or as consequence of metabolic disorders such as diabetes. Neuropathic pain is most often a chronic condition, and can be associated with anxiety and depression; thus, it negatively impacts quality of life. Several pharmacologic approaches exist; however, they can lead numerous adverse effects. From this perspective, the use of nutraceuticals and diet supplements can be helpful in relieve neuropathic pain and related symptoms. In this review, we discuss how diet can radically affect peripheral neuropathy, and we focus on the potential approaches to ameliorate this condition, such as the use of numerous nutritional supplements or probiotics.

The Impact of General Anesthesia on Redox Stability and Epigenetic Inflammation Pathways: Crosstalk on Perioperative Antioxidant Therapy

Worldwide, the prevalence of surgery under general anesthesia has significantly increased, both because of modern anesthetic and pain-control techniques and because of better diagnosis and the increased complexity of surgical techniques. Apart from developing new concepts in the surgical field, researchers and clinicians are now working on minimizing the impact of surgical trauma and offering minimal invasive procedures due to the recent discoveries in the field of cellular and molecular mechanisms that have revealed a systemic inflammatory and pro-oxidative impact not only in the perioperative period but also in the long term, contributing to more difficult recovery, increased morbidity and mortality, and a negative financial impact. Detailed molecular and cellular analysis has shown an overproduction of inflammatory and pro-oxidative species, responsible for augmenting the systemic inflammatory status and making postoperative recovery more difficult. Moreover, there are a series of changes in certain epigenetic structures, the most important being the microRNAs. This review describes the most important molecular and cellular mechanisms that impact the surgical patient undergoing general anesthesia, and it presents a series of antioxidant therapies that can reduce systemic inflammation.

Vitamin C and cancer risk and treatment

Vitamin C (L-ascorbic acid) works as a strong reductant, radical scavenger, and protector of cell membranes against primary peroxidative damage in tissues and in the extracellular fluid. L-ascorbic acid is involved in the synthesis of collagen and many other biologically relevant substances, enzyme activity, xenobiotic detoxification, and prevention of forming carcinogenic nitrosamines. It also plays a role in the immune system. Numerous data indicate that cancer patients suffer from vitamin C deficiency. Studies show that people with a low vitamin C intake have an increased risk of head and neck cancers as well as lung, gastric, pancreatic, cervical, rectal, or breast cancer. On the other hand, there is no clinical evidence to support the thesis that antioxidant supplements (including vitamin C) prevent cancer. Observational trials investigating high doses of intravenous L-ascorbic acid in previously treated cancer patients have shown that it allows an increase in quality of life and may improve physical, mental, and emotional functions, as well as reducing adverse effects of standard anticancer treatment, including fatigue, nausea, vomiting, and appetite loss. So far, there were a few randomized controlled trials and they have not reported any statistically significant improvements in the overall or progression-free survival with vitamin C, as compared to the control arm. However, preclinical data indicating a role of L-ascorbic acid in modulation of immune response and its involvement in epigenome remodeling suggest its new potential clinical applications in cancer patients, especially in combination with immunotherapy. It seems reasonable to further investigate the value of vitamin C as a supportive treatment or in combination with anticancer targeted therapy.

Non-drug pain relievers active on non-opioid pain mechanisms

This review is aimed to summarize the pain-relieving effect of non-drug substances, mostly prescribed as integrators in treatment of pain, including especially in chronic postoperative pain (CPSP) and in chronic back pain after acute episodes. Their use reflects the fact that the current treatments for these syndromes continue to pose problems of unsatisfactory responses in a significant portion of patients and/or of an excess of side effects like those noted in the present opioid crisis. As integrators are frequently introduced into the market without adequate clinical testing, this review is aimed to collect the present scientific evidence either preclinical or clinical for their effectiveness. In particular, we reviewed the data on the use of: B vitamins; vitamin C; vitamin D; alpha lipoic acid (ALA); N-acetylcysteine; acetyl L-carnitine; curcumin; boswellia serrata; magnesium; coenzyme Q10, and palmitoylethanolamide. The combination of preclinical findings and clinical observations strongly indicate that these compounds deserve more careful attention, some of them having interesting clinical potentials also in preventing chronic pain after an acute episode. In particular, examining their putative mechanisms of action it emerges that combinations of few of them may exert an extraordinary spectrum of activities on a large variety of pain-associated pathways and may be eventually used in combination with more traditional pain killers in order to extend the duration of the effect and to lower the doses. Convincing examples of effective combinations against pain are vitamin B complex plus gabapentin for CPSP, including neuropathic pain; vitamin B complex plus diclofenac against low back pain and also in association with gabapentin, and ALA for burning mouth syndrome. These as well as other examples need, however, careful controlled independent clinical studies confirming their role in therapy.

Clinical efficacy and safety of oral and intravenous vitamin C use in patients with malignant diseases

Background

Vitamin C, also called ascorbic acid, is a water-soluble antioxidant and free radical scavenger. It is required in the body for numerous metabolic functions and is involved in the development of proteins and connective tissue.

Methods

In April 2020, a systematic search was carried out on five electronic databases (Medline, Embase, Cochrane, Cinahl, PsycINFO) to find studies on the use, efficacy and safety of a complementary therapy with vitamin C in oncological patients.

Results

Out of the initial 23,195 search results, 21 studies with 1961 patients were included in this review. Five of the included studies (n = 417) were randomized controlled trials (RCTs). The remaining 16 studies belonged to a lower class of evidence. The patients who were treated with vitamin C suffered from various malignant diseases, some in an advanced and palliative stage. Vitamin C was applied intravenously or orally. It was either the only treatment or was combined with chemo- or radiotherapy. Endpoints included the development of the disease-related symptoms, quality of life, mortality, progression-free survival and safety of vitamin C. The studies were of moderate quality and showed either no effect of vitamin C or a positive trend, although this has rarely been statistically proven in group comparisons. No or only slight side effects with both oral and intravenous administration of vitamin C were reported.

Conclusion

Oral intake of vitamin C does not appear to have any effect in patients with malignancies. Data are heterogeneous for intravenous administration. There are no RCTs with statistical group comparisons.

Nonsurgical Approaches to Neuroma Management

Symptomatic neuromas and chronic neuropathic pain are significant problems affecting patients' quality of life and independence that are challenging to treat. These symptoms are due to structural and functional changes that occur peripherally within neuromas, as well as alterations that occur centrally within the brain and spinal cord. A multimodal approach is most effective, with goals to minimize opioid use, to capitalize on the synergistic effects of nonopioid medications and to explore potential benefits of novel adjunctive treatments.

Dimethyl Fumarate Reduces Oxidative Stress and Pronociceptive Immune Responses in a Murine Model of Complex Regional Pain Syndrome

BACKGROUND

Complex regional pain syndrome (CRPS) is a highly disabling cause of pain often precipitated by surgery or trauma to a limb. Both innate and adaptive immunological changes contribute to this syndrome. Dimethyl fumarate (DMF) works through the nuclear factor erythroid 2-related factor 2 (Nrf2) transcription factor and other targets to activate antioxidant systems and to suppress immune system activation. We hypothesized that DMF would reduce nociceptive, functional, and immunological changes measured in a model of CRPS.

METHODS

Male C57BL/6 mice were used in the well-characterized tibial fracture model of CRPS. Some groups of mice received DMF 25 mg/kg/d orally, per os for 3 weeks after fracture versus vehicle alone. Homozygous Nrf2 null mutant mice were used as test subjects to address the need for this transcription factor for DMF activity. Allodynia was assessed using von Frey filaments and hindlimb weight-bearing data were collected. The markers of oxidative stress malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) were quantified in the skin of the fractured mice using immunoassays along with the innate immune system cytokines IL-1β and IL-6. The accumulation of IgM in the fractured limbs and lymph node hypertrophy were used as indexes of adaptive immune system activation, and the passive transfer of serum from wildtype fractured mice to B cell-deficient fractured muMT mice (mice lacking B cells and immunoglobulin) helped to assess the pronociceptive activity of humoral factors.

RESULTS

We observed that oral DMF administration strongly prevented nociceptive sensitization and reduced uneven hindlimb weight bearing after fracture. DMF was also very effective in reducing the accumulation of markers of oxidative stress, activation of innate immune mediator production, lymph node hypertrophy, and the accumulation of IgM in fractured limbs. The sera of fractured vehicle-treated but not DMF-treated mice conferred pronociceptive activity to recipient mice. Unexpectedly, the effects of DMF were largely unchanged in the Nrf2 null mutant mice.

CONCLUSIONS

Oxidative stress and immune system activation are robust after hindlimb fracture in mice. DMF strongly reduces activation of those systems, and the Nrf2 transcription factor is not required. DMF or drugs working through similar mechanisms might provide effective therapy for CRPS or other conditions where oxidative stress causes immune system activation.

Ascorbic Acid in the Acute Care Setting

Ascorbic acid (AA) is an essential nutrient with many physiologic roles not limited to the prevention of scurvy. Beyond its role as a supplement, it has gained popularity in the acute care setting as an inexpensive medication for a variety of conditions. Because of limitations with absorption of oral formulations and reduced serum concentrations observed in acute illness, intravenous (IV) administration, and higher doses, may be needed to produce the desired serum concentrations for a particular indication. Following a PubMed search, we reviewed published studies relevant to AA in the acute care setting and summarized the results in a narrative review. In the acute care setting, AA may be used for improved wound healing, improved organ function in sepsis and acute respiratory distress syndrome, faster resolution of vasoplegic shock after cardiac surgery, reduction of resuscitative fluids in severe burn injury, and as an adjunctive analgesic, among other uses. Each indication differs in its level of evidence supporting exogenous administration of AA, but overall, AA was not commonly associated with adverse effects in the identified studies. Use of AA remains an active area of clinical investigation for various indications in the acute care patient population.

Feasibility of Vitamin C in the Treatment of Post Viral Fatigue with Focus on Long COVID, Based on a Systematic Review of IV Vitamin C on Fatigue

Fatigue is common not only in cancer patients but also after viral and other infections. Effective treatment options are still very rare. Therefore, the present knowledge on the pathophysiology of fatigue and the potential positive impact of treatment with vitamin C is illustrated. Additionally, the effectiveness of high-dose IV vitamin C in fatigue resulting from various diseases was assessed by a systematic literature review in order to assess the feasibility of vitamin C in post-viral, especially in long COVID, fatigue. Nine clinical studies with 720 participants were identified. Three of the four controlled trials observed a significant decrease in fatigue scores in the vitamin C group compared to the control group. Four of the five observational or before-and-after studies observed a significant reduction in pre-post levels of fatigue. Attendant symptoms of fatigue such as sleep disturbances, lack of concentration, depression, and pain were also frequently alleviated. Oxidative stress, inflammation, and circulatory disorders, which are important contributors to fatigue, are also discussed in long COVID fatigue. Thus, the antioxidant, anti-inflammatory, endothelial-restoring, and immunomodulatory effects of high-dose IV vitamin C might be a suitable treatment option.

Intravenous Administration of Vitamin C in the Treatment of Herpes Zoster-Associated Pain: Two Case Reports and Literature Review

Background

Herpes zoster (HZ) is an acute inflammatory neurocutaneous disease caused by the reactivation of varicella-zoster virus. It is estimated that the incidence of postherpetic neuralgia following HZ is 10–20%. The leading risk factors of the prognosis are aging and immunity dysfunction. Vitamin C plays a pivoted role in enhancing white blood cell function. Epidemiological evidence and clinical studies have indicated an association between pain and suboptimal vitamin C status. At present, vitamin C has been used as an additional option in the treatment of HZ-associated pain. Despite the current controversy, case reports and randomized controlled studies have indicated that both acute- and postherpetic neuralgia can be dramatically alleviated following intravenous vitamin C infusions. Case Presentation. Two patients (male aged 72 and female 78 years) with HZ did not respond well to antiviral therapy and analgesics. Skin lesions in the right groin and front thigh healed after early antiviral therapy, but the outbreak of pain persisted in the male patient. The female patient presented to our clinic with clusters of rashes in the right forehead with severe edema of her right upper eyelid. Because nerve blockade could not be conducted for both patients, intravenous infusion of vitamin C was applied and resulted in an immediate remission of the breakthrough pain in the male patient and cutaneous lesions in the female patient.

Conclusions

The use of vitamin C appears to be an emerging treatment alternative for attenuating HZ and PHN pain. Hence, we recommend the addition of concomitant use of intravenously administered vitamin C into therapeutic strategies in the treatment of HZ-associated pain, especially for therapy-resistant cases. Furthermore, animal studies are required to determine analgesic mechanisms of vitamin C, and more randomized clinical trials are essential to further determine the optimal dose and timing of administration of vitamin C.

The Effects of Surgery on Plasma/Serum Vitamin C Concentrations: A Systematic Review and Meta-Analysis

Vitamin C (ascorbic acid) is a water soluble vitamin with an array of biological functions. A number of proposed factors contribute to the vitamin’s plasma bioavailability and ability to exert optimal functionality. The aim of this review was to systematically assess plasma vitamin C levels post-surgery compared with pre-surgery/ the magnitude and timeframe of potential changes in concentration. We searched the PUBMED, SCOPUS, SciSearch and the Cochrane Library databases between 1970 to April 2020 for relevant research papers. Prospective studies, control groups and true placebo groups derived from controlled trials that reported means and standard deviations of plasma vitamin C concentrations pre and post operatively were included into the meta-analysis. Data were grouped into short-term (≤7 days) and long term (> 7 days) post-operative follow-up. 23 of 31 studies involving 642 patients included in the systematic review were suitable for meta-analysis. Pooled data from the meta-analysis revealed a mean depletion of plasma vitamin C concentration of -17.99 µmol/L (39% depletion) (CI = -22.81, -13.17) (trial arms = 25, n = 565, p < 0.001) during the first post-operative week and -18.80 µmol/L (21% depletion) (-25.04, -12.56) (trial arms = 6, n = 166, p < 0.001) 2-3 months post-operatively. Subgroup analyses revealed that these depletions occurred following different types of surgery, however, high heterogeneity was observed amongst trials assessing concentration change during the first post-operative week. Overall, our results warrant larger, long term investigations of changes in post-operative plasma vitamin C concentrations and their potential effects on clinical symptomology.

Opioid-Sparing Effect of Liposomal Bupivacaine and Intravenous Acetaminophen in Colorectal Surgery

BACKGROUND

This study evaluated the opioid-sparing effect of liposomal bupivacaine and intravenous acetaminophen in colorectal surgery.

MATERIALS AND METHODS

This study was a retrospective, 2 × 2 factorial cohort conducted at an academic medical center from May 2016 to February 2018. Patients undergoing open or minimally invasive colorectal resection were included. Exclusion criteria were age <18 y, surgery after second hospital day, ostomy, and allergy to acetaminophen, opioids, or bupivacaine. Intraoperative liposomal bupivacaine and intravenous acetaminophen administration within 18 h after surgery were evaluated. The primary outcome was intravenous morphine milligram equivalents administered within 24 h after surgery. A linear regression model adjusted for American Society of Anesthesiologists score, enhanced recovery after surgery management, open surgery, opioid use before surgery, and height was used for the primary analysis.

RESULTS

Among 486 included patients, 193 received both liposomal bupivacaine and intravenous acetaminophen, 93 received liposomal bupivacaine only, 104 received intravenous acetaminophen only, and 96 did not receive either. On average, patients received 21 (SD = 31) morphine equivalents over 24 h. Intraoperative liposomal bupivacaine was associated with a reduction of morphine equivalents (adjusted change -11, 95% CI -17 to -6), but intravenous acetaminophen was not (2, 95% CI -3 to 7). Intraoperative liposomal bupivacaine was associated with a reduction of length of stay (adjusted change = -1.2 d, 95% CI -2.1 to -0.3), but intravenous acetaminophen was not (adjusted change = 1.5 d, 95% CI 0.7 to 2.2).

CONCLUSIONS

Liposomal bupivacaine was associated with a significant reduction of opioid use within 24 h after colorectal surgery, but intravenous acetaminophen was not.

The Effect of Perioperative Vitamin C on Postoperative Analgesic Consumption: A Meta-Analysis of Randomized Controlled Trials

Because the analgesic effect of vitamin C against acute pain remains poorly addressed, this meta-analysis aimed at investigating its effectiveness against acute postoperative pain. A total of seven randomized controlled trials with placebo/normal controls were identified from PubMed, Cochrane Library, Medline, Google Scholar, and Embase databases. Pooled analysis showed a lower pain score (standardized mean difference (SMD) = -0.68, 95% CI: -1.01 to -0.36, p < 0.0001; I2 = 57%) and a lower morphine consumption (weighted mean difference (WMD) = -2.44 mg, 95% CI: -4.03 to -0.86, p = 0.003; I2 = 52%) in the vitamin group than that in the placebo group within postoperative 1-2 h. At postoperative 24 h, a lower pain score (SMD = -0.65, 95% CI: -1.11 to -0.19, p = 0.005; I2 = 81%) and lower morphine consumption (WMD = -6.74 mg, 95% CI: -9.63 to -3.84, p < 0.00001; I2 = 85%) were also noted in the vitamin group. Subgroup analyses demonstrated significant reductions in pain severity and morphine requirement immediately (1-2 h) and 24 h after surgery for patients receiving intravenous vitamin C but not in the oral subgroup. These findings showed significant reductions in pain score and opioid requirement up to postoperative 24 h, respectively, suggesting the effectiveness of perioperative vitamin C use. Further large-scale trials are warranted to elucidate its optimal intravenous dosage and effectiveness against chronic pain in the postoperative pain control setting.

Glutathione and Glutathione-Like Sequences of Opioid and Aminergic Receptors Bind Ascorbic Acid, Adrenergic and Opioid Drugs Mediating Antioxidant Function: Relevance for Anesthesia and Abuse

Opioids and their antagonists alter vitamin C metabolism. Morphine binds to glutathione (l-γ-glutamyl-l-cysteinyl-glycine), an intracellular ascorbic acid recycling molecule with a wide range of additional activities. The morphine metabolite morphinone reacts with glutathione to form a covalent adduct that is then excreted in urine. Morphine also binds to adrenergic and histaminergic receptors in their extracellular loop regions, enhancing aminergic agonist activity. The first and second extracellular loops of adrenergic and histaminergic receptors are, like glutathione, characterized by the presence of cysteines and/or methionines, and recycle ascorbic acid with similar efficiency. Conversely, adrenergic drugs bind to extracellular loops of opioid receptors, enhancing their activity. These observations suggest functional interactions among opioids and amines, their receptors, and glutathione. We therefore explored the relative binding affinities of ascorbic acid, dehydroascorbic acid, opioid and adrenergic compounds, as well as various control compounds, to glutathione and glutathione-like peptides derived from the extracellular loop regions of the human beta 2-adrenergic, dopamine D1, histamine H1, and mu opioid receptors, as well as controls. Some cysteine-containing peptides derived from these receptors do bind ascorbic acid and/or dehydroascorbic acid and the same peptides generally bind opioid compounds. Glutathione binds not only morphine but also naloxone, methadone, and methionine enkephalin. Some adrenergic drugs also bind to glutathione and glutathione-like receptor regions. These sets of interactions provide a novel basis for understanding some ways that adrenergic, opioid and antioxidant systems interact during anesthesia and drug abuse and may have utility for understanding drug interactions.

Ascorbic acid for management of oral surgery pain not responding to conventional medication: case report

Introduction: A 20-year-old female who experienced severe pain during six weeks after dental treatment was followed by oral surgeries. This article focuses on the usage of high dose of oral L-ascorbic acid for pain alleviation which did not respond to conventional pain medication. Observation: A female patient complaining about severe pain in tooth number 31 which was measured at every visit she made to the office, using Numerical Rating Pain Scale (NRPS) as the model for registration. Comments: Implementation of different types of analgesics along with laser-therapy were not able to reduce patient's ache during forty four consecutive days. Pain relief was only obtained at the next day with L-ascorbic acid supplementation to patient's previous medication. A complete absence of pain was reported by the patient on the seventh day after the ascorbate intake. Conclusion: Given to its action of mediating a variety of essential biological and biochemical functions, benefits, low cost, and safety, L-ascorbic acid could be considered by general dentists and oral surgeons as possible pain modulator after oral/dental surgical procedures.

Vitamin C, Pain and Opioid Use Disorder

Vitamin C (ascorbic acid, AA) is an essential nutrient in humans. It is vital to a multitude of metabolic pathways, including those affecting mental health, stress response, and pain perception. This paper provides a review of the literature and a theoretical perspective on the potential roles of AA in the treatment of pain and opioid use disorder (OUD). A powerful antioxidant and anti-inflammatory agent involved in glutathione recycling, AA is a cofactor in adrenal steroidogenesis and catecholamine biosynthesis. AA supports the synthesis of serotonin, modulates synaptic dopamine and glutamate, and may also enhance the synthesis of endomorphins and endorphins. In animal models, AA reduces and prevents opioid drug tolerance and physical dependency. It irreversibly inactivates opioid stereospecific binding, while increasing the antinociceptive effects of pain medications. In clinical trials, AA has been proven safe and effective in acute and chronic pain relief, including ambulatory, surgical, and oncological settings. AA may temper the need for opioids, which raises the question of whether it can help reduce the risk of OUD onset. High, frequent doses of AA may also abort cravings and opioid withdrawal symptoms in those with OUD and has better tolerability than other OUD treatments. Further clinical trials on the potential of AA in the prevention and treatment of OUD are warranted.

Comparison of the effects of preoperative melatonin or vitamin C administration on postoperative analgesia

The analgesic benefit of melatonin and vitamin C as primary or adjuvant agents has been reported in various studies; however, their analgesic effects in the treatment of postoperative pain remain unclear. Thus, we aimed to evaluate the effect of single preoperative dose of oral melatonin or vitamin C administration on postoperative analgesia. In this study, we recruited 165 adult patients undergoing elective major abdominal surgery under general anesthesia. Patients were randomly divided into three equal (n = 55) groups. One hour before surgery, patients received orally melatonin (6 mg) in group M, vitamin C (2 g) in group C, or a placebo tablet in group P. Pain, sedation, patient satisfaction, total morphine consumption from a patient-controlled analgesia device, supplemental analgesic requirement, and the incidence of nausea and vomiting were recorded throughout 24 h after surgery. The mean pain score and total morphine consumption were found significantly lower in both M and C groups compared with group P (p < 0.001). There were no significant differences between group M and C with respect to pain scores (p = 0.117) and total morphine consumption (p = 0.090). Patients requested less supplemental analgesic and experienced less nausea and vomiting in groups M and C compared with group P. In conclusion, preoperative oral administration of 6 mg melatonin or 2 g vitamin C led to a reduction in pain scores, total morphine consumption, supplemental analgesic requirement, and the incidence of nausea and vomiting compared with placebo.

Additional effect of magnesium sulfate and vitamin C in laparoscopic gynecologic surgery for postoperative pain management: a double-blind randomized controlled trial

Background

This clinical trial was conducted to determine whether combined use of magnesium sulfate and vitamin C more significantly reduced postoperative fentanyl consumption and pain than magnesium sulfate or vitamin C alone.

Methods

The prospective, double-blinded, randomized controlled study enrolled 132 patients scheduled for laparoscopic gynecologic surgery. The patients were randomly allocated to one of the four groups (n = 33 for each group; Group M [magnesium sulfate 40 mg/kg], Group V [vitamin C 50 mg/kg], Group MV [magnesium sulfate 40 mg/kg and vitamin C 50 mg/kg] and Group C [isotonic saline 40 ml]). Cumulative postoperative fentanyl consumption (primary endpoint measure), postoperative pain score by numeric rating scale, and postoperative nausea and vomiting were recorded at 1, 6, 24, and 48 h after discharge from the postanesthesia care unit.

Results

Cumulative postoperative fentanyl consumption was significantly less in Groups M, V, and MV than in Group C at all time points. Group MV showed significantly less cumulative postoperative fentanyl consumption than Group M at postoperative 24 h (mean ± standard deviation, 156.6 ± 67.5 vs. 235.6 ± 94.6 µg, P = 0.001), as well as significantly less consumption than Groups M and V at postoperative 48 h (190.8 ± 74.6 vs. 301.0 ± 114.8 or 284.1 ± 128.6 µg, P < 0.001, P = 0.003, respectively).

Conclusions

Combined use of magnesium sulfate and vitamin C provides an additional benefit in postoperative pain management after laparoscopic gynecologic surgery in comparison to single administration of magnesium sulfate or vitamin C.

ANALGESIC EFFECT OF INTRAVENOUS ASCORBIC ACID VERSUS ACELCOFENAC POST-TRANSALVEOLAR EXTRACTION: A CASE-CONTROL STUDY

One of the most important aspects of postsurgical care is finding an efficient way for the management of pain. Third molar extractions/surgical impaction is one of the most frequent surgical procedures in dental hospitals, and it is most often associated with postoperative complications like severe pain, oedema and reduced mouth opening. This study was aimed to evaluate the efficacy of 2 g intravenous (IV) vitamin C compared to 100 mg aceclofenac on postsurgical pain, swelling and trismus after the surgical removal of third molars. A total of 101 patients were recruited for the study, and theywere divided into two treatment groups; group A (n = 51) received 2 g IV vitamin C and group B (n = 50) received 100 mg aceclofenac. Pain intensity, facial swelling and mouth opening were assessed till day 3 post-surgically. Statistical analysis of pain intensity revealed that IV vitamin C performed slightly better but not significantly different (p>0.05) from aceclofenac group at the end of day 3. No significant difference for facial swelling and mouth opening between the two treatment protocols was seen (p>0.05). Our results concluded that both treatment groups were overall similar in analgesic efficacy, postoperative oedema and reduction in mouth opening. It was also determined that the method devised administering 2 g IV vitamin C intravenously was well suited to the treatment of postoperative pain, swelling and trismus following the surgical extraction of impacted third molars.

Vitamin C Can Shorten the Length of Stay in the ICU: A Meta-Analysis

A number of controlled trials have previously found that in some contexts, vitamin C can have beneficial effects on blood pressure, infections, bronchoconstriction, atrial fibrillation, and acute kidney injury. However, the practical significance of these effects is not clear. The purpose of this meta-analysis was to evaluate whether vitamin C has an effect on the practical outcomes: length of stay in the intensive care unit (ICU) and duration of mechanical ventilation. We identified 18 relevant controlled trials with a total of 2004 patients, 13 of which investigated patients undergoing elective cardiac surgery. We carried out the meta-analysis using the inverse variance, fixed effect options, using the ratio of means scale. In 12 trials with 1766 patients, vitamin C reduced the length of ICU stay on average by 7.8% (95% CI: 4.2% to 11.2%; p = 0.00003). In six trials, orally administered vitamin C in doses of 1⁻3 g/day (weighted mean 2.0 g/day) reduced the length of ICU stay by 8.6% (p = 0.003). In three trials in which patients needed mechanical ventilation for over 24 hours, vitamin C shortened the duration of mechanical ventilation by 18.2% (95% CI 7.7% to 27%; p = 0.001). Given the insignificant cost of vitamin C, even an 8% reduction in ICU stay is worth exploring. The effects of vitamin C on ICU patients should be investigated in more detail.

Ascorbic Acid in Colon Cancer: From the Basic to the Clinical Applications

Given the safety and potential benefits of intravenous ascorbic acid (AA) administration in cancer patients, there is merit in further exploring this therapeutic concept. In this review, we discuss the potential benefits of intravenous AA administration on colorectal cancer and we specifically focus on its effect on glycolysis in mutant and wild type RAS. We perform a PubMed and Ovid MEDLINE search using ascorbic acid, intravenous vitamin C, KRAS mutation, BRAF mutation and colorectal cancer (CRC) as keywords. At the cellular level, colorectal cancer cells undergo a metabolic shift called the Warburg effect to allow for more glucose absorption and utilization of glycolysis. This shift also allows AA to enter which leads to a disruption in the Warburg effect and a shutdown of the downstream KRAS pathway in mutated KRAS colon cancer cells. At the clinical level, AA is associated with tumour regression in advanced disease and improved tolerability and side effects of standard therapy. Based on these findings, we conclude that further clinical trials are needed on a larger scale to examine the therapeutic benefits of AA in colon cancer.

Pharmacologic interventions for fatigue in cancer and transplantation: a meta-analysis

Background

Our objective was to determine whether, compared with control interventions, pharmacologic interventions reduce the severity of fatigue in patients with cancer or recipients of hematopoietic stem-cell transplantation (hsct).

Methods

For a systematic review, we searched medline, embase, the Cochrane Central Register of Controlled Trials, cinahl, and Psychinfo for randomized trials of systemic pharmacologic interventions for the management of fatigue in patients with cancer or recipients of hsct. Two authors independently identified studies and abstracted data. Methodologic quality was assessed using the Cochrane Risk of Bias tool. The primary outcome was fatigue severity measured using various fatigue scales. Data were synthesized using random-effects models.

Results

In the 117 included trials (19,819 patients), the pharmacologic agents used were erythropoietins (n = 31), stimulants (n = 19), l-carnitine (n = 6), corticosteroids (n = 5), antidepressants (n = 5), appetite stimulants (n = 3), and other agents (n = 48). Fatigue was significantly reduced with erythropoietin [standardized mean difference (smd): -0.52; 95% confidence interval (ci): -0.89 to -0.14] and with methylphenidate (smd: -0.36; 95% ci: -0.56 to -0.15); modafinil (or armodafinil) and corticosteroids were not effective.

Conclusions

Erythropoietin and methylphenidate significantly reduced fatigue severity in patients with cancer and in recipients of hsct. Concerns about the safety of those agents might limit their usefulness. Future research should identify effective interventions for fatigue that have minimal adverse effects.

An Insight and Update on the Analgesic Properties of Vitamin C

Pain is an unpleasant subjective feeling having implications on both physical and mental realm. Multiple dimensions of pain involving behavioral, spiritual, emotional, and cognitive changes have been studied and pathways elucidated. It is stressed that the nature in which pain is modulated and perceived at a higher center is a complex phenomenon. One of the main goals of pain modulation is to modify pain to a more tolerable level, rather than its complete eradication. Different pain management interventions were tried but have effects that are more adverse. Till date, the only reliable pain blockers are analgesics and anti-inflammatory drugs in the form of opioids and non-opioids. Despite this, most of the drugs are ineffective at various levels, furthermore, adding to complications. Thus, there is an urgent need for effective intervention with minimal side effects. Ascorbic acid, popularly known as vitamin C, has shown to exhibit promising analgesic properties. The literature is sparse with the usage of the drug in various forms of pain. This review focuses on the dynamics and kinetics of vitamin C and its usage in various forms of pain. With minimal adverse effects, the drug is shown to perform well in different types of pain disorders, thus paving way for alternative interventional agent for pain management.

The role of vitamin C in the treatment of pain: new insights

The vitamin C deficiency disease scurvy is characterised by musculoskeletal pain and recent epidemiological evidence has indicated an association between suboptimal vitamin C status and spinal pain. Furthermore, accumulating evidence indicates that vitamin C administration can exhibit analgesic properties in some clinical conditions. The prevalence of hypovitaminosis C and vitamin C deficiency is high in various patient groups, such as surgical/trauma, infectious diseases and cancer patients. A number of recent clinical studies have shown that vitamin C administration to patients with chronic regional pain syndrome decreases their symptoms. Acute herpetic and post-herpetic neuralgia is also diminished with high dose vitamin C administration. Furthermore, cancer-related pain is decreased with high dose vitamin C, contributing to enhanced patient quality of life. A number of mechanisms have been proposed for vitamin C’s analgesic properties. Herein we propose a novel analgesic mechanism for vitamin C; as a cofactor for the biosynthesis of amidated opioid peptides. It is well established that vitamin C participates in the amidation of peptides, through acting as a cofactor for peptidyl-glycine α-amidating monooxygenase, the only enzyme known to amidate the carboxy terminal residue of neuropeptides and peptide hormones. Support for our proposed mechanism comes from studies which show a decreased requirement for opioid analgesics in surgical and cancer patients administered high dose vitamin C. Overall, vitamin C appears to be a safe and effective adjunctive therapy for acute and chronic pain relief in specific patient groups.