An observational study on salivary conductivity for fluid status assessment and clinical relevance in acute ischemic stroke during intravenous fluid hydration.

The body fluid status in acute stroke is a crucial determinant in early stroke recovery but a real-time method to monitor body fluid status is not available. This study aims to evaluate the relationship between salivary conductivity and body fluid status during the period of intravenous fluid hydration. Between June 2020 to August 2022, patients presenting with clinical signs of stroke at the emergency department were enrolled. Salivary conductivities were measured before and 3 h after intravenous hydration. Patients were considered responsive if their salivary conductivities at 3 h decreased by more than 20% compared to their baseline values. Stroke severity was assessed using the National Institutes of Health Stroke Scale, and early neurological improvement was defined as a decrease of ≥ 2 points within 72 h of admission. Among 108 recruited patients, there were 35 of stroke mimics, 6 of transient ischemic attack and 67 of acute ischemic stroke. Salivary conductivity was significantly decreased after hydration in all patients (9008 versus 8118 µs/cm, p = 0.030). Among patients with acute ischemic stroke, the responsive group, showed a higher rate of early neurological improvement within 3 days compared to the non-responsive group (37% versus 10%, p = 0.009). In a multivariate logistic regression model, a decrease in salivary conductivity of 20% or more was found to be an independent factor associated with early neurological improvement (odds ratio 5.42, 95% confidence interval 1.31-22.5, p = 0.020). Real-time salivary conductivity might be a potential indicator of hydration status of the patient with acute ischemic stroke.

A Portable Biodevice to Monitor Salivary Conductivity for the Rapid Assessment of Fluid Status.

The evaluation of fluid status can save adults from life-threatening conditions, but the current methods are invasive or time-consuming. Therefore, we developed a portable device for measuring salivary conductivity. This prospective observational study enrolled 20 volunteers with no history of systemic diseases. Participants were observed for 13 h, including water restriction for 12 h followed by rehydration with 1000 mL water within 1 h. Serum and urine biomarkers for fluid status, thirst scales, and salivary conductivity were collected during dehydration and rehydration. No significant differences in age, body mass index, glycohemoglobin, and estimated glomerular filtration rate were noted between sexes. Salivary conductivity increased after water restriction and decreased after rehydration. Similarly, urine osmolality, urine specific gravity, thirst intensity scales, and body weight followed the same trend and were statistically significant. The angiotensin-converting enzyme and aldosterone levels showed the same trend, without reaching statistical significance. The red blood cell count and hemoglobin concentration also followed the same trend. Analyzing the receiver operating characteristic curves, the area under the curve was 0.707 (95% confidence interval 0.542-0.873, p = 0.025). Using the Youden index, the optimal cutoff determined as 2678.09 µs/cm (sensitivity: 90%, specificity: 55%). This biodevice effectively screened dehydration among healthy adults.

Diffusion tensor imaging for assessment of microstructural changes associate with treatment outcome at one-year after radiofrequency Rhizotomy in trigeminal neuralgia.

BACKGROUND: Trigeminal neuralgia (TN) is characterized by facial pain that may be sudden, intense, and recurrent. Neurosurgical interventions, such as radiofrequency rhizotomy, can relieve TN pain, but their mechanisms and effects are unknown. The aim of the present study was to investigate the microstructural tissue changes of the trigeminal nerve (TGN) in patients with TN after they underwent radiofrequency rhizotomy. METHODS: Thirty-seven patients with TN were recruited, and diffusion tensor imaging was obtained before and two weeks after radiofrequency rhizotomy. By manually selecting the cisternal segment of the TGN, we measured the volume of the TGN, fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (AD), and radial diffusivity (RD). The TGN volume and mean value of the DTI metrics of the post-rhizotomy lesion side were compared with those of the normal side and those of the pre-rhizotomy lesion side, and they were correlated to the post-rhizotomy visual analogue scale (VAS) pain scores after a one-year follow-up. RESULTS: The alterations before and after rhizotomy showed a significantly increased TGN volume and FA, and a decreased ADC, AD, and RD. The post-rhizotomy lesion side showed a significantly decreased TGN volume, FA, and AD compared with the normal side; however, no significant difference in the ADC and RD were found between the groups. The TGN volume was significantly higher in the non-responders than in the responders (P = 0.016). CONCLUSION: Our results may reflect that the effects of radiofrequency rhizotomy in TN patients include axonal damage with perineural edema and that prolonged swelling associated with recurrence might be predicted by MRI images. Further studies are necessary to understand how DTI metrics can quantitatively represent the pathophysiology of TN and to examine the application of DTI in the treatment of TN.

A Novel "Maximizing Kappa" Approach for Assessing the Ability of a Diagnostic Marker and Its Optimal Cutoff Value.

Threshold-dependent accuracy measures such as true classification rates in ordered multiple-class (k > 3) receiver operating characteristic (ROC) hyper-surfaces have recently been used to assist with medical decision making. However, based on low power performance in some circumstances, we construct a new method that relies on the kappa coefficient to solve such diagnostic problems. Under the approach proposed in the present article, the statistics depend strongly on the [Formula: see text] cutoff threshold, which can be chosen to maximize the kappa statistics of true disease status and of the new biomarker. The Monte Carlo simulation results confirm the effectiveness of the proposed method in terms of its predictive power. The proposed design is then compared with the volume under the ROC hyper-surface by applying it to intracerebral hemorrhagic patients classified into five stroke classes using the National Institutes of Health Stroke Scale.

The impact factors on the cost and length of stay among acute ischemic stroke.

BACKGROUND: Understanding hospital costs and length of stay (LOS) can optimize the in-hospital management of acute stroke. We investigated cost and LOS in first-ever and recurrent stroke patients in Taiwan. METHODS: Data were examined in patients at Chang Gung Memorial Hospital in Chiayi County of Taiwan from April 1, 2008, to March 31, 2010 [corrected]. Predictors of hospital cost and LOS in these patients were studied. RESULTS: The study included 1021 patients with 1084 stroke episodes. Mean age was 68.1 ± 10.8 years (range: 32-93). The average cost was NTD$45,709.30 ± NTD$66,697.40 (US$1408.70 ± US$2084.30; US$1 = NTD$32) and average LOS was 13.9 ± 14.1 days (range: 1-129). After multivariate regression analysis, the significant predictive factors for cost were LOS, smoking, and medication for secondary prevention. The significant predictive factors for LOS were diabetes mellitus, atrial fibrillation, recurrence, and stroke subtype. CONCLUSIONS: Age 65 and over, atrial fibrillation, stroke treatment, and subtypes were the significant predictive factors affecting hospital costs and LOS. Compared to other countries, Taiwan spent the least while Canada had the highest expense. The United States had the shortest LOS (6 days) in contrast to Canada with the longest LOS (34-47 days). Regarding mean daily cost of stroke, the United States had the highest cost per day while China spent the least.