Anxiolytic effects of vestibular stimulation: an update.

The vestibular system inhibits both HPA and SAM axis and contributes to the management of anxiety. Both direct and indirect pathways exist in the inhibition of the HPA and SAM axis. In this review article, the authors describe various pathways through which the vestibular system can regulate the HPA and SAM axis activity. Lastly, the authors highlight the need of starting translational research work in this field. Rocking is soothing and this is a universal fact that babies in the swing will calm down and sleep. These soothing effects of vestibular stimulation may be due to the inhibition of cortical and subcortical structures. Vestibular stimulation may be able to manage anxiety through its connections with multiple brain areas. There is a need to undertake translational research in this area to establish strong scientific evidence and recommend implementation of the vestibular stimulation in the management of anxiety.

Comparison of the Utilization of Tranexamic Acid and Tourniquet Use in Total Knee Arthroplasty: A Retrospective Case Series.

INTRODUCTION: Total knee arthroplasty (TKA) carries a high risk for significant blood loss due to bone cuts and extensive soft tissue involvement in the knee region. The use of tranexamic acid (TXA) or a tourniquet are two methods commonly employed to prevent significant blood loss and avoid the need for blood transfusion. TXA has been shown to reduce both intraoperative and postoperative bleeding as well as the probability that a patient will require a blood transfusion. The purpose of this study is to compare the efficacy of TXA and tourniquet use, both alone and in combination, in reducing blood loss during TKA. METHODS: Data for this retrospective cohort study were obtained by searching records of patients who underwent TKA at a tertiary care center from January 2019 to October 2020. Data from 526 subjects were available. A chart review was conducted to determine if the patient received TXA only, tourniquet only, or both TXA and tourniquet during the TKA procedure. Primary outcomes for this study including procedure length in minutes, estimated blood loss in cubic centimeters, and total infusion pressor (phenylephrine) administered intraoperatively in milligrams were recorded for the study. Data were summarized using means and standard errors. Statistical methods used for analysis include one-way ANOVA, probability plots, the Shapiro-Wilk test for normality, the Kruskal-Wallis test, and Tukey's test. RESULTS: Data were available for 526 subjects. 122 subjects received tourniquet only (Tourniquet group), 104 received intravenous (IV) TXA only, 264 received both tourniquet and IV TXA (Tourniquet + TXA), and 36 received neither tourniquet nor TXA (None). The groups did not significantly differ in procedure length (p = 0.140) or infusion pressor total (p > 0.20). The groups did significantly differ in estimated blood loss (p < 0.001). Subjects who did not receive either TXA or tourniquet had significantly more blood loss than the Tourniquet and Tourniquet + TXA groups. Similarly, the TXA group had significantly more blood loss than both the Tourniquet and Tourniquet + TXA groups. CONCLUSION: This study supports the conclusion that the use of a tourniquet is superior to the use of TXA in reducing intraoperative blood loss during TKA. All groups that underwent TKA using a tourniquet, either alone or in combination with TXA, exhibited significantly lower levels of blood loss compared to the control (no intervention) group.

Electrical vestibular nerve stimulation (VeNS): a follow-up safety assessment of long-term usage.

OBJECTIVES: This retrospective, open-label study was undertaken to assess the safety of repeated, long-term electrical vestibular nerve stimulation (VeNS). The primary outcome for this study was assessment of hearing function as reported by formal audiometry testing. METHODS: Assessments were conducted on n=25 long-term users of daily 1.5 mA VeNS. Skin inspection of the mastoid area, otoscope examination of the inner ear, and formal audiometry testing was conducted on n=18 users. All participants completed a survey-based assessment to determine usage of the device, adverse events, and long-term outcomes. RESULTS: Mean duration of use was 22 months, with approximately 80% of users reporting 1 h of daily, or 1 h of regular (2-3 times per week) VeNS usage. No adverse events were reported. There were no significant findings during examination of the mastoid areas, ear canal, or tympanic membranes. There were no significant findings reported from the formal audiogram assessments. CONCLUSIONS: This appears to be the first study to provide formal assessment to show that repeated, long-term VeNS usage has not generated any significant side effects or adverse events. Results from this study further support previous literature that electrical vestibular stimulation is both safe and well-tolerated.

Acceptability and feasibility of a vestibular nerve stimulation headset protocol in children with cerebral palsy.

BACKGROUND: Research suggests electrical Vestibular Nerve Stimulation (VeNS) may improve balance for people with neurological impairments. This study aimed to assess the feasibility and acceptability of a VeNS headset protocol in children with cerebral palsy (CP). METHODS: Children aged 5-18 years with ambulant CP, their parents, and healthcare professionals were recruited via social media. Children completed a battery of balance tests and wore a sham VeNS headset one hour per day for four weeks. Perspectives on the balance tests and headset were ascertained from children, parents and healthcare professionals using semi-structured interviews. Interview data were analysed thematically. RESULTS: Two families and four healthcare professionals participated. Balance outcome measures were fully completed and deemed acceptable. Adherence with wearing the headset was 89-100% but discomfort with self-adhesive electrodes was reported. Four themes emerged from interview data: headset issues, perceptions about VeNS, the importance of balance, and modifications for future study. CONCLUSIONS: Although the VeNS headset had high acceptability, the volunteer sample was small, potentially suggesting limited interest in VeNS as a treatment for children with CP, or reluctance to trial a 'non-active' headset. Recruitment via clinicians known to the family and use of an 'active' headset may increase participation in future research.

Modulation of sleep using electrical vestibular nerve stimulation prior to sleep onset: a pilot study.

OBJECTIVES: Electrical stimulation of the vestibular system (VeNS) has been shown to improve Insomnia Severity Index (ISI) when delivered during sleep. We hypothesize that repeated electrical vestibular stimulation, when delivered prior to sleep onset, will improve ISI scores. The primary aim of this study was to assess the effect that VeNS had on ISI scores when delivered prior to sleep onset. A secondary aim was to provide initial data indicating "length of time to effect" that will allow more appropriate design of a larger randomized control trial (RCT). METHODS: The present study was an experimental study (pre and post without control). The participants acted as self-controls. After recording the baseline values, electrical vestibular nerve stimulation was administered as intervention once in a day for 30 min, 1 h prior to sleep onset using ML1000 device (Neurovalens, UK) for 14 days. RESULTS: There was significant decrease in the ISI scores followed by the electrical vestibular nerve stimulation. Further, participants reported a significant increase in well-rested sleep post the intervention period. CONCLUSIONS: This study supports our hypothesis that VeNS has a positive impact on ISI scores when delivered on a regular basis prior to sleep onset.

Anti-diabetic effect of vestibular stimulation is mediated via AMP-activated protein kinase.

There is abundant animal evidence that vestibular stimulation, particularly of the otolith organs, can trigger a shift in body mass composition towards a leaner physique. One way of non-invasively stimulating the otolith organs is via a small electrical current applied to the skin behind the ears. This technique is called vestibular nerve stimulation, or VeNS, and is believed to have a good safety profile. Thus, it has previously been argued that VeNS could be used in human health as a means of treating the complications of metabolic syndrome, such as obesity and type 2 diabetes mellitus. Weight loss itself is known to improve diabetic control, however, tantalizing evidence is now emerging that the improvements seen in the glycemic control of type 2 diabetics who undergo repeated vestibular stimulation are significantly better than would be expected on the basis of weight loss alone. As vestibular stimulation has been shown to increase levels of an anti-inflammatory protein, called sirtuin 1, we hypothesize here that VeNS will increase levels of an associated enzyme called AMP-activated protein kinase (AMPK). AMPK plays an important role in glucose and fat metabolism and is activated by exercise, as well as being a known target for certain anti-diabetic drugs. This hypothesis is readily amenable to clinical testing as specific assays for testing human AMPK are available. If substantiated, then this hypothesis could prove an important clinical insight and potentially offer a new treatment avenue for patients with type 2 diabetes; a condition which remains a major cause of morbidity and premature mortality worldwide.

Electrical vestibular nerve stimulation as an adjunctive therapy in the management of type 2 diabetes.

OBJECTIVES: Vestibular nerve stimulation using the portable battery-operated vestibular nerve stimulator is a sophisticated method noninvasive, safe, and easy to operate. It was hypothesized that vestibular nerve stimulation is effective in the management of type 2 diabetes. Hence, the present study was undertaken to determine the effectiveness of vestibular nerve stimulation using portable battery-operated vestibular nerve stimulator in the management of diabetes. METHODS: The present study was a double-blind randomized controlled trial with 1:1 split between the control and experimental groups. A total of 30 participants with type 2 diabetes were part of the study after obtaining the written informed consent. After recording the baseline values, the vestibular nerve stimulation was administered to the participants in the intervention group for 90 days. Sham stimulation was administered to the control group for 90 days. Outcome measures were recorded after 30 days and after 90 days of the intervention in both the groups. RESULTS: There was significant decrease in the total body weight, fasting, postprandial blood glucose, glycosylated hemoglobin levels, leptin, very low density lipoproteins levels followed by the intervention. There was significant improvement in both spatial and verbal memory scores. Depression and stress scores and systolic blood pressure decreased and remained in normal limits. CONCLUSIONS: The study results have proven multimodal action of vestibular stimulation. It not only acts on regulation of the glucose metabolism but also can regulate the autonomic activity and improve cognition and relieve stress. This is the interesting finding of our study, which needs detailed further research to support implementation of vestibular nerve stimulation as an adjunctive therapy in the management of diabetes.

Pain Management Issues for the Geriatric Surgical Patient.

Adequate treatment of pain is of utmost importance in making uncomplicated the perioperative course for geriatric surgical patients. Effective analgesia reduces morbidity, improves patient and family satisfaction, and is a natural expectation of high-quality care. Pain treatment in older adults is more complicated than in younger counterparts, and great consideration must be given to age-related changes in physiology and pharmacokinetics. Pain treatment must be individualized based on each patient's profile. Side effects must be minimized and organ toxicity avoided. When complications occur they may be more severe, and treatment must be prompt. Alternative plans for analgesia must be readily enacted.

Intravenous lidocaine reduces ischemic pain in healthy volunteers.

BACKGROUND AND OBJECTIVES: Lidocaine, a local anesthetic and antiarrhythmic drug that alters depolarization in neurons by blocking the fast voltage-gated sodium (Na+) channels in the cell membrane, is used for regional anesthesia, as antiarrhythmic drug, and as analgesic for various painful conditions. It is unclear whether monotherapy with intravenous lidocaine has an analgesic effect in healthy individuals. To address this important question, we studied pain perception before, during, and after the administration of intravenous lidocaine in 16 human volunteers. Our hypothesis was that lidocaine, administered as a short intravenous infusion, does not have an analgesic effect in healthy volunteers. METHODS: Sixteen healthy human volunteers received systemic lidocaine at plasma concentration 2 mg/mL using a computer-assisted infusion. Participants underwent a series of sensory tests-thermal, electrical, and ischemic pain and normal pinprick sensation-at baseline, during, and 30 mins after administration of a 20-min lidocaine infusion at a 2 mg/mL effect site concentration. RESULTS: We found a sustained decrease in ischemic pain ratings and a limited analgesic effect for electrical pain, whereas thermal pain and normal sensation did not change. CONCLUSIONS: The observed sustained analgesic effect of systemic lidocaine in the ischemic pain model suggests that lidocaine may be used to treat acute pain.