Elevated blood urea nitrogen/creatinine ratio is associated with poor outcome in patients with ischemic stroke

Prevalence of hypohydration and its association with stroke severity and independence outcomes in acute ischemic stroke patients

Hypohydration has been suggested increasing the risk of vascular diseases, and it is associated with poor prognosis and worse functional outcome in stroke. Most studies have used blood parameters to determine patients' hydration status. The aim of this study was to measure urine osmolality (uOsm) and its influence on stroke severity and independence. A prospective descriptive study was conducted in stroke patients admitted to a stroke unit. All patients underwent neurological evaluation at admission and discharge using the National Institute of Health Stroke Scale (NIHSS). Independence at discharge was evaluated with the Barthel Index (BI) and the modified Rankin Scale (mRS). uOsm was measured at admission. Patients were grouped in "poor fluid intake" (PF) and "euhydration" (EU), the latter if uOsm ≤ 500 mOsm/kg. Among 119 included patients, the prevalence of PF was 52%, with no difference observed between groups in demographics or blood samples analyses. PF had higher chances of NIHSS > 8 at admission (OR: 4.7 95% CI: 1.3-17.0; p = 0.02), lower BI at discharge (β: -15.3 95% CI: -26.7 to -3.8; p = 0.01), and worse mRS at discharge (OR: 4.01 95% CI: 1.2-14.0; p = 0.02). These findings are consistent with previous results, suggesting that uOsm may be a factor significantly associated with stroke severity and independence outcome after acute ischemic stroke.

Preoperative Dehydration does not Increase the Risk of Complications Following Elective Lumbar Surgery

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

The aim of this study was to evaluate the effect of preoperative dehydration on hospital length of stay (LOS), rates of 30-day postoperative complications, related reoperations, and readmissions.

SUMMARY OF BACKGROUND DATA

Preoperative dehydration has long been associated with postoperative infection, deep vein thrombosis (DVT), acute renal failure, and an increased hospital LOS. To our knowledge, the effect of preoperative dehydration on complication rates for patients undergoing elective lumbar spine surgery has not been well described.

METHODS

An analysis of American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) data from 2006 to 2013 was performed. Patients undergoing elective lumbar procedures were identified and exclusion criteria eliminated patients who underwent any emergency procedures, infections, tumor cases, or revision surgeries. Patient dehydration was defined as preoperative blood urea nitrogen/creatinine (BUN/Cr) ratio greater than 20.

RESULTS

Patients (4698; 34.5%) with preoperative dehydration based on BUN/Cr ratio were identified. Univariate analysis was suggestive of an association between preoperative dehydration and an increased risk of DVT (1.1% compared with 0.6%; P = 0.002), urinary tract infection (2.5% compared with 1.6%; P < 0.001), and need for transfusion postoperatively (17.6% compared with 14.4%; P < 0.001). However, on the basis of multivariate regression, no significant association between dehydration and increased odds of aforementioned outcomes was identified.

CONCLUSION

Preoperative dehydration does not appear to negatively affect perioperative outcomes or readmission in patients undergoing elective lumbar spine surgery.

LEVEL OF EVIDENCE

3.

Perfusion Enhancement with Respiratory Impedance After Stroke (PERI-Stroke)

Intrathoracic pressure influences cardiac output and may affect cerebral blood flow (CBF). We aimed to quantify the cerebral hemodynamic response to intrathoracic pressure reduction in patients with acute ischemic stroke using a noninvasive respiratory impedance (RI) device. We assessed low-level (6 cm H2O) and high-level (12 cm H2O) RI in 17 spontaneously breathing patients within 72 h of anterior circulation acute ischemic stroke. Average age was 65 years, and 35% were female. Frontal lobe tissue perfusion and middle cerebral artery velocity (MCAv) were continuously monitored with optical diffuse correlation spectroscopy (DCS) and transcranial Doppler ultrasound, respectively. High-level RI resulted in a 7% increase in MCAv (p = 0.004). MCAv varied across all studied levels (baseline vs low-level vs high-level, p = 0.006), with a significant test of trend (p = 0.002). Changes were not seen in DCS measured tissue perfusion by nonparametric pairwise comparison. Mixed effects regression analysis identified a small increase in both MCAv (low-level RI: β 2.1, p < 0.001; high-level RI: β 5.0, p < 0.001) and tissue-level flow (low-level RI: β 5.4, p < 0.001; high-level RI: β 5.9, p < 0.001). There was a small increase in mean arterial pressure during low-level and high-level RI, 4% (p = 0.013) and 4% (p = 0.017), respectively. End-tidal CO2 remained stable throughout the protocol. RI was well tolerated. Manipulating intrathoracic pressure via noninvasive RI was safe and produced a small but measurable increase in cerebral perfusion in acute ischemic stroke patients. Future studies are warranted to assess whether RI is feasible and tolerable for prolonged use in hyperacute stroke management.

Association between Blood Urea Nitrogen-to-creatinine Ratio and Three-Month Outcome in Patients with Acute Ischemic Stroke

Background:

Hydration status significantly affects the clinical outcome of acute ischemic stroke (AIS) patients. Blood urea nitrogen-to-creatinine ratio (BUN/Cr) is a biomarker of hydration status. However, it is not known whether there is a relationship between BUN/Cr and three-month outcome as assessed by the modified Rankin Scale (mRS) score in AIS patients.

Methods:

AIS patients admitted to West China Hospital from 2012 to 2016 were prospectively and consecutively enrolled and baseline data were collected. Poor clinical outcome was defined as three-month mRS > 2. Univariate and multivariate logistic regression analyses were performed to determine the relationship between BUN/Cr and three-month outcome. Confounding factors were identified by univariate analysis. Stratified logistic regression analysis was performed to identify effect modifiers.

Results:

A total of 1738 patients were included in the study. BUN/Cr showed a positive correlation with the three-month outcome (OR 1.02, 95% CI 1.00-1.03, p=0.04). However, after adjusting for potential confounders, the correlation was no longer significant (p=0.95). An interaction between BUN/Cr and high-density lipoprotein (HDL) was discovered (p=0.03), with a significant correlation between BUN/Cr and three-month outcome in patients with higher HDL (OR 1.03, 95% CI 1.00-1.07, p=0.04).

Conclusion:

Elevated BUN/Cr is associated with poor three-month outcome in AIS patients with high HDL levels.

Fluid Balance Variations During the Early Phase of Large Hemispheric Stroke Are Associated With Patients' Functional Outcome

Background: From the variety of factors underlying the ischemia-associated edema formation in large hemispheric stroke (LHS), an increased brain water content during the early phase seems to have a pivotal role for long-lasting tissue damage. However, the importance of the fluid management during the acute phase of LHS has so far not been adequately studied. Therefore, this study explored the association between the fluid balance and functional outcome in patients suffering from LHS. Methods: We analyzed hospital-based medical records of 39 consecutive patients with LHS and decompressive hemicraniectomy. Over the first 10 days after admission, the volumes of all administered fluids were assessed daily and corrected for daily urinary output and insensible loss. Functional outcome at 3 months was assessed with the modified Rankin Scale (mRS) and dichotomized into an acceptable (mRS ≤ 4) vs. a poor outcome (mRS ≥ 5). Results: Compared to patients with a poor functional outcome (n = 19), those with an acceptable outcome (n = 20) were characterized by a significantly lower cumulative net fluid balance at day 5 (1.6 ± 2.5 vs. 3.4 ± 4.4 l), day 7 (2.0 ± 2.9 vs. 4.6 ± 5.2 l), and day 10 (0 ± 2.5 vs. 5.6 ± 6.2 l). In addition to age, only the cumulative net fluid balance at day 10 served as an independent factor for poor functional outcome in multiple regression analyses. Conclusion: These data provide evidence for a critical role of the early phase net fluid balance with respect to the functional outcome after LHS. This observation leads to the hypothesis that patients with LHS might benefit from a more restrictive volume therapy. However, prospective studies are warranted to establish a causal relationship and recommendations for treatment strategies.

Contribution of dehydration to END in acute ischemic stroke not mediated via coagulation activation

OBJECTIVE

Dehydration is a risk factor for early neurological deterioration (END) after ischemic stroke, yet the underlying mechanism is unclear. Outbalanced coagulation activation may contribute to ischemia progression, concurrently with dehydration-induced blood viscosity change. We aimed to investigate whether the contribution of dehydration to END was mediated by blood coagulation activation.

METHODS

We retrospectively evaluated consecutive patients presenting with mild or moderate stroke (National Institutes of Health Stroke Scale score ≤14) within 24 hr of onset between Jan 2016 and Dec 2017. Dehydration was defined by a serum nitrogen to creatinine ratio (BUN/Cr) of ≥15 and blood coagulation activity was assessed with thromboelastography (TEG). The correlations between BUN/Cr and TEG parameters were assessed and their relationship in the development of END was analyzed.

RESULTS

Of 244 patients, 64 (26.2%) developed END within 3 days after admission. Patients with END had significantly higher BUN/Cr (19.2 ± 5.7 vs. 15.3 ± 2.9, p = 0.008), shorter R and K on TEG test (R: 3.9 ± 1.0 vs. 4.6 ± 1.1, p = 0.001; K: 1.3 ± 0.5 vs. 1.5 ± 0.4, p = 0.005). Comparison between patients with and without dehydration revealed no significant differences in TEG parameters. Multivariate regression suggested that dehydration status (OR 3.91, 95%CI 2.17-8.67, p = 0.008) and shorter R tercile on TEG (OR 3.18, 95% CI 1.23-7.90, p = 0.016) were independently associated with END; however, the odds ratio of R for END remained unchanged after adjustment for dehydration status.

CONCLUSION

Our findings suggested that the contribution of dehydration to END after ischemic stroke was mediated by blood coagulation activation.

A multidisciplinary consensus on dehydration: definitions, diagnostic methods and clinical implications

Background: Dehydration appears prevalent, costly and associated with adverse outcomes. We sought to generate consensus on such key issues and elucidate need for further scientific enquiry. Materials and methods: A modified Delphi process combined expert opinion and evidence appraisal. Twelve relevant experts addressed dehydration's definition, objective markers and impact on physiology and outcome. Results: Fifteen consensus statements and seven research recommendations were generated. Key findings, evidenced in detail, were that there is no universally accepted definition for dehydration; hydration assessment is complex and requires combining physiological and laboratory variables; "dehydration" and "hypovolaemia" are incorrectly used interchangeably; abnormal hydration status includes relative and/or absolute abnormalities in body water and serum/plasma osmolality (pOsm); raised pOsm usually indicates dehydration; direct measurement of pOsm is the gold standard for determining dehydration; pOsm >300 and ≤280 mOsm/kg classifies a person as hyper or hypo-osmolar; outside extremes, signs of adult dehydration are subtle and unreliable; dehydration is common in hospitals and care homes and associated with poorer outcomes. Discussion: Dehydration poses risk to public health. Dehydration is under-recognized and poorly managed in hospital and community-based care. Further research is required to improve assessment and management of dehydration and the authors have made recommendations to focus academic endeavours. Key messages Dehydration assessment is a major clinical challenge due to a complex, varying pathophysiology, non-specific clinical presentations and the lack of international consensus on definition and diagnosis. Plasma osmolality represents a valuable, objective surrogate marker of hypertonic dehydration which is underutilized in clinical practice. Dehydration is prevalent within the healthcare setting and in the community, and appears associated with increased morbidity and mortality.

Effects of the blood urea nitrogen to creatinine ratio on haemorrhagic transformation in AIS patients with diabetes mellitus

Background

The effect of the blood urea nitrogen (BUN) to creatinine (Cr) ratio (henceforth BUN/Cr) on haemorrhagic transformation (HT) of acute ischaemic stroke (AIS) patients is unclear.

Methods

AIS patients in the West China Hospital, Sichuan University, Chengdu, China, admitted within seven days from stroke onset (2012–2016) were included in the study. Baseline data, including BUN and Cr levels, were collected. The outcome was defined as HT during hospitalization.

Results

In this study, 1738 participants with an average age of 62.7 ± 14.0 years were included. After adjusting potential confounders (age, blood platelet, albumin, stroke severity, triglycerides and low-density lipoprotein [LDL]), multivariate logistic regression analyses indicated that BUN/Cr is independently associated with HT. The nonlinear relation between BUN/Cr and HT was explored in a dose-dependent manner, with an apparent inflection point of 30.71. On the left and right sides of the inflection point, the odds ratio (OR) and 95% confidence interval (CI) were 1.05 (1.02–1.08) and 0.96 (0.88–1.05), respectively. Interaction between BUN/Cr and diabetes mellitus (DM) and HT (P for interaction = 0.0395) was noted. BUN/Cr showed positive correlation with HT in DM patients (OR = 1.07; 95% CI: [1.02, 1.12]) but no significant relationship with HT in patients without DM.

Conclusion

BUN/Cr is significantly associated with HT in AIS patients in a linear fashion, with an apparent cut point demarcating the HT difference. When the patients have DM, BUN/Cr is positively correlated with HT. These results support a revision in how we anticipate the prognosis for AIS patients.

Electronic supplementary material

The online version of this article (10.1186/s12883-019-1290-x) contains supplementary material, which is available to authorized users.

Frequency, Risk Factors, and Prognosis of Dehydration in Acute Stroke

Objective: To determine the frequency, risk factors, and impact on the outcome of dehydration after stroke. Methods: In this cross-sectional observational study, we included prospectively and consecutively patients with ischemic and hemorrhagic stroke. The serum Urea/Creatinine ratio (U/C) was calculated at admission and 3 days after the stroke. Dehydration was defined as U/C>80. Patients were treated in accordance with the standard local hydration protocol. Demographic and clinical data were collected. Neurological severity was evaluated at admission according to the NIHSS score; functional outcome was assessed with the modified Rankin scale score (mRS) at discharge and 3 months after the stroke. Unfavorable outcome was defined as mRS > 2. Results: We evaluated 203 patients; 78.8% presented an ischemic stroke and 21.2% a hemorrhagic stroke. The mean age was 73.4 years ±12.9; 51.7% were men. Dehydration was detected in 18 patients (8.9%), nine patients at admission (4.5%), and nine patients (4.5%) at 3 days after the stroke. Female sex (OR 3.62, 95%CI 1.13-11.58, p = 0.03) and older age (OR 1.05, 95%CI 1-1.11, p = 0.048) were associated with a higher risk of dehydration. Dehydration was significantly associated with an unfavorable outcome at discharge (OR 5.16, 95%CI 1.45-18.25, p = 0.011), but the association was not significant at 3 months (OR 2.95, 95%CI 0.83-10.48, p = 0.095). Conclusion: Dehydration is a treatable risk factor of a poor functional outcome after stroke that is present in 9% of patients. Females and elders present a higher risk of dehydration.

Management of Blood Pressure During and After Recanalization Therapy for Acute Ischemic Stroke

Ischemic stroke is a common neurologic condition and can lead to significant long term disability and death. Observational studies have demonstrated worse outcomes in patients presenting with the extremes of blood pressure as well as with hemodynamic variability. Despite these associations, optimal hemodynamic management in the immediate period of ischemic stroke remains an unresolved issue, particularly in the modern era of revascularization therapies. While guidelines exist for BP thresholds during and after thrombolytic therapy, there is substantially less data to guide management during mechanical thrombectomy. Ideal blood pressure targets after attempted recanalization depend both on the degree of reperfusion achieved as well as the extent of infarction present. Following complete reperfusion, lower blood pressure targets may be warranted to prevent reperfusion injury and promote penumbra recovery however prospective clinical trials addressing this issue are warranted.

Effects of Dehydration on Brain Perfusion and Infarct Core After Acute Middle Cerebral Artery Occlusion in Rats: Evidence From High-Field Magnetic Resonance Imaging

Background: Dehydration is common among ischemic stroke patients and is associated with early neurological deterioration and poor outcome. This study aimed to test the hypothesis that dehydration status is associated with decreased cerebral perfusion and aggravation of ischemic brain injury. Methods: Diffusion-weighted imaging and arterial spin labeling perfusion MR imaging were performed on rats with middle cerebral artery occlusion (MCAO) by using a 9.4T MR imaging scanner to measure the volume of infarction and relative cerebral blood flow (rCBF) after infarction. Twenty-five rats were assigned to either a dehydration group or normal hydration group, and dehydration status was achieved by water deprivation for 48 h prior to MCAO. Results: The volume of the infarction was significantly larger for the dehydration group at the 4th h after MCAO (p = 0.040). The progression in the infarct volume between the 1st and 4th h was also larger in the dehydration group (p = 0.021). The average rCBF values of the contralateral normal hemispheres at the 1st and the 4th h were significantly lower in the dehydration group (p = 0.027 and 0.040, respectively). Conclusions: Our findings suggested that dehydration status is associated with the progression of infarct volume and decreases in cerebral blood flow during the acute stage of ischemic stroke. This preliminary study provided an imaging clue that more intensive hydration therapies and reperfusion strategies are necessary for the management of acute ischemic stroke patients with dehydration status.

Predictive Value of Baseline Biochemical Parameters for Clinical Response of Macular Edema to Bevacizumab in Eyes With Central Retinal Vein Occlusion: A Retrospective Analysis

PURPOSE

To evaluate the influence of baseline biochemical parameters on the improvement in best corrected visual acuity (BCVA) and reduction in central foveal thickness (CFT) in patients treated with intravitreal bevacizumab (IVB; Avastin, Genentech, Inc) for macular edema (ME) secondary to central retinal vein occlusion (CRVO).

DESIGN

A retrospective study.

METHODS

Seventy eyes of 70 participants with CRVO who underwent IVB for ME and had at least 1 month of follow-up after the last injection were studied. Demographic variables, systolic and diastolic blood pressure (SBP and DBP), BCVA, CFT measured by optical coherence tomography (OCT), and biochemical investigations [hemoglobin, fasting and postprandial blood sugar (FBS and PPBS), lipid profile, blood urea (BU), serum creatinine (SC), glycosylated hemoglobin (HbA1c)] at baseline were noted. IVB need at every visit was based on clinical and OCT parameters. Changes in BCVA (ΔBCVA) and CFT (ΔCFT) from baseline to last injection were estimated.

RESULTS

After IVB, there was a statistically significant reduction in mean CFT (P < 0.01). The group of patients with normal BU and SC had more than 2 lines of improvement compared with those with elevated values (P = 0.043 and 0.009, respectively). Other parameters like FBS, PPBS, hemoglobin, HbA1c, and serum lipids were not associated with improvement of BCVA and reduction of CFT.

CONCLUSIONS

Normal baseline renal parameters (BU and SC) predict better visual outcome after treatment for ME in CRVO and offer additional benefit over and above that obtained with ME reduction.

Use of Oral Hydration Protocols for Dysphagic Patients Following Stroke

PURPOSE

The aim of the study was to describe the use of oral hydration protocols for dysphagic patients following stroke.

DESIGN AND METHODS

We reviewed inpatient records for patients able to take food and liquids orally within 30 days of an ischemic stroke. Orders were hierarchically defined with three levels of liquid consistency modification (LCM) and six levels of augmented hydration orders (AHOs). Change from admission to discharge in hydration and functional independence measure (FIM) scores across LCM and AHO groups was assessed.

FINDINGS

Length of stay, admission FIM, discharge FIM, and change in FIM scores were all significantly related to LCM and AHO group assignment. Need for supplemental intravenous hydration was low (6.9%) over the 2-year study period and was significantly related to both LCM and AHO group assignment.

CONCLUSION AND CLINICAL RELEVANCE

The association of LCM and AHO interventions with functional outcomes and need for intravenous fluids helps to validate their clinical utility.

Prediction of neurologic deterioration based on support vector machine algorithms and serum osmolarity equations

OBJECTIVE

Dehydration on admission is correlated with neurological deterioration (ND). The primary objective of our study was to use support vector machine (SVM) algorithms to identify an ND prognostic model, based on dehydration equations.

METHODS

This study included a total of 382 patients hospitalized with acute ischemic stroke. The following parameters were recorded: age, sex, laboratory values (serum sodium, potassium, chlorinum, glucose, and urea), and vascular risk factor data. Receiver operating characteristic (ROC) curve analysis was used to evaluate the discriminative performance of the BUN/Cr ratio as well as each of 38 equations for predicting ND. We used the Boruta algorithm for feature selection. After optimizing the SVM kernel parameters, we built an SVM model to predict ND and used the test set to obtain predictive values for assessing model accuracy.

RESULTS

In total, 102 of 382 patients (26.7%) with acute ischemic stroke developed ND. In all patients, the BUN/Cr ratio and each of 38 equations were significant predictors of ND. Equation 20 [1.86 × Na+ + glucose + urea + 9] yielded the maximum area under the ROC curve, and faired best in terms of prognostic performance (a cutoff value of 284.49 mM yielded a sensitivity of 94.12% and specificity of 61.43%). Equation 32 predicted ND poststroke across population groups, and worked well in older as well as young adults; (a cutoff value of 297.08 mM yielded a sensitivity of 93.14% and specificity of 60.00%). Feature selection by the Boruta algorithm was used to decrease the number of variables from 18 to 5 in the condition. The specificity of test samples for the SVM prediction model increased from 44.1% to 89.4%, and the AUC increased from 0.700 to 0.927.

CONCLUSIONS

SVM algorithms can be used to establish a prediction model for dehydration-associated ND, with good classification results.

Hydration prevents chronic hyperglycaemic patients from neurological deterioration post-ischaemic stroke

OBJECTIVES

To determine whether chronic hyperglycaemia predisposes patients to dehydration, which may promote neurological deterioration, and to investigate whether dehydration control improves functional outcome.

PATIENTS AND METHODS

This study included 355 patients hospitalized with acute ischaemic stroke and diabetes mellitus who fulfilled the glycaemic gap ≤0. We used the following cut-offs: (i) no chronic hyperglycaemia (glycated haemoglobin A1c [HbA1c] < 7%) and (ii) chronic hyperglycaemia (HbA1c ≥ 7%). The chronic hyperglycaemic patients were randomly divided into the control group and the hydration group. Hydration therapy was only initiated in the hydration group. The blood urea nitrogen (BUN)/creatinine (Cr) ratio was used as an indicator of dehydration. Stroke severity on admission and discharge was assessed by means of National Institutes of Health Stroke Scale (NIHSS).

RESULTS

The mean baseline BUN/Cr ratios were higher in the control group and hydration group than in the no chronic hyperglycaemia group. The mean BUN/Cr ratio decreased from 91.22 ± 29.95 on the first day to 77.03 ± 18.23 on the third day (P < .001) in the hydration group. On the third day after admission, there was no significant difference in the BUN/Cr ratio between the hydration group and the no chronic hyperglycaemia group (P = .831). Moreover, neurological deterioration was highest in the control group (33.6%, 36/107), followed by the hydration group (10.5%, 11/105) and the no chronic hyperglycaemia group (5.6%, 8/143).

CONCLUSIONS

Chronic hyperglycaemia was associated with the admission NIHSS score and neurological deterioration after excluding the effect of stress hyperglycaemia. Furthermore, hydration therapy may help prevent neurological deterioration.

Primary 'dehydration' and acute stroke: a systematic research review

BACKGROUND AND PURPOSE

Hydration status at the time of stroke has been acknowledged as an important determinant in early stroke recovery. However, the diagnosis of dehydration, or more accurately, a volume-contracted state, at the time of stroke is challenging since there are currently no consensus diagnostic criteria. In this systematic review, we gather the available evidence about diagnosis and treatment of dehydration after stroke.

METHODS

Studies of hospitalized ischemic stroke patients that reported rates of dehydration from January 1997 to March 2017 were screened for inclusion via a systematic search of PubMed, CINAHL, Cochrane, and Scopus using keywords hydration, dehydration, hemodilution, viscosity, volume status, and thirst.

RESULTS

Twenty-five studies of 8699 acute stroke patients were included. Nineteen studies reported on the diagnostic approach to dehydration. Findings are synthesized into four main categories of available research including studies that specify: (1) biological mechanisms using animal models to investigate the relationship between dehydration and stroke; (2) measures of dehydration in the acute human stroke population; (3) rehydration therapies after stroke; and (4) outcomes after stroke in dehydrated patients.

CONCLUSIONS

We found considerable variation in terminology specific to hydration status, diagnostic approach to dehydration, and few prospective studies of treatment strategies with varying results. This review supports the need for consensus development of operational diagnostic criteria, standardization of language, and the opportunity for prospective study of rehydration strategies to impact outcome after stroke.

Pilot study of volume contracted state and hospital outcome after stroke

BACKGROUND

An increasing body of research suggests that acute stroke patients who are dehydrated may have worsened functional outcomes. We sought to explore the relationship between a volume contracted state (VCS) at the time of ischemic stroke and hospital outcomes as compared with euvolemic patients.

METHODS

We enrolled a consecutive series of ischemic stroke patients from a single academic stroke center within 12 hours from stroke onset. VCS was defined via surrogate markers (blood urea nitrogen/creatinine ratio >15 and urine specific gravity >1.010). The primary outcome was change in NIH Stroke Scale (NIHSS) score from admission to discharge. Multivariable analyses included adjustment for demographics and infarct size.

RESULTS

Over an 11-month study period, 168 patients were eligible for inclusion. Of the126 with complete laboratory and MRI data, 44% were in a VCS at the time of admission. Demographics were similar in both the VCS and euvolemic groups, as were baseline NIHSS scores (6.7 vs 7.3; p = 0.63) and infarct volumes (12 vs 16 mL; p = 0.48). However, 42% of patients in a VCS demonstrated early clinical worsening, compared with 17% of the euvolemic group (p = 0.02). A VCS remained a significant predictor of worsening NIHSS in adjusted models (odds ratio 4.34; 95% confidence interval 1.75-10.76).

CONCLUSIONS

Acute stroke patients in a VCS demonstrate worse short-term outcomes compared to euvolemic patients, independent of infarct size. Results suggest an opportunity to explore current hydration practices.

Impact of blood urea nitrogen to creatinine ratio on mortality and morbidity in hemodialysis patients: The Q-Cohort Study

The association between blood urea nitrogen to creatinine ratio (UCR) and survival is uncertain in hemodialysis patients. We examined the influence of UCR on mortality and morbidity in hemodialysis patients. A total of 3,401 hemodialysis patients were prospectively followed for 4 years. The association between UCR with overall survival was analyzed using a Cox regression model. During a 4-year follow-up period, 545 patients died from any cause and 582 experienced MACE, 392 with coronary heart disease (CHD), 114 with infection-related death, 77 with hemorrhagic stroke, 141 with ischemic stroke, and 107 with cancer death. Every 1 increase in UCR level was significantly associated with an increased risk for all-cause mortality (hazard ratio [HR] 1.07; 95% confidence interval [CI] 1.03–1.12), CHD (HR 1.08; 95% CI 1.02–1.14), and infection-related death (HR 1.11; 95% CI 1.02–1.21). There was no evidence of a significant association between UCR and death from cancer, and incidence of stroke. A high UCR was significantly associated with an increased risk for all-cause mortality, infection-related death and incidence of CHD in hemodialysis patients.

Dehydration is a strong predictor of long-term prognosis of thrombolysed patients with acute ischemic stroke

BACKGROUND AND PURPOSE

Dehydration was found to be involved in the poor prognosis of patients with acute ischemic stroke. It is unclear whether dehydration status before onset is related with prognosis of thrombolysed patients with acute ischemic stroke. If it is the case, quickly hydrating may improve the prognosis. The present study was designed to explore the issue.

METHODS

Eligible 294 patients with acute ischemic stroke after thrombolysis were enrolled in the present study according to inclusion/exclusion criteria. According to the modified Rankin scale (mRS) 90 days post stroke, the patients were divided into two groups: mRS 0-2 (n = 191) and mRS 3-6 (n = 103). In the present study, BUN/Cr ≥ 15 combined with USG > 1.010 or either of them were chosen as dehydration marker. Clinical data were analyzed between two groups. Univariate and multivariate statistical analyses were carried out.

RESULTS

Age, fibrinogen, blood glucose, BUN/Cr, NIHSS score at admission, the systolic blood pressure (SBP) before thrombolysis, dehydration status (BUN/Cr ≥ 15 plus USG > 1.010), hyperlipidemia, USG and D-dimer on admission day, and TOAST classification showed significant difference between two groups (p < .05). Further stratification analysis showed that BUN/Cr ≥ 15, NIHSS ≥ 6, blood glucose ≥8, and SBP > 150 were markedly associated with poor outcome (mRS 3-6, p < .05). After adjusting for age, fibrinogen, USG, D-dimer, dehydration status, NIHSS, blood glucose, SBP, hyperlipidemia, and BUN/Cr at admission, multivariate logistic regression showed that dehydration status, higher NIHSS, higher blood glucose, and higher SBP at admission were independent risk factors for predicting the long-term poor prognosis of thrombolysed patients.

CONCLUSIONS

The present findings suggest that BUN/Cr ≥ 15 combined with USG > 1.010 as a marker of dehydration status was an independent risk factor for long-term poor prognosis of thrombolysed patients with acute ischemic stroke.

Volume of Plasma Expansion and Functional Outcomes in Stroke

BACKGROUND

Plasma expansion in acute ischemic stroke has potential to improve cerebral perfusion, but the long-term effects on functional outcome are mixed in prior trials. The goal of this study was to evaluate how the magnitude of plasma expansion affects neurological recovery in acute stroke.

METHODS

This was a secondary analysis of data from the Albumin in Acute Stroke Part 2 trial investigating the relationship between the magnitude of overall intravenous volume infusion (crystalloid and colloid) to clinical outcome. The data were inclusive of 841 patients with a mean age of 64 years and a median National Institutes of Health Stroke Scale (NIHSS) of 11. In a multivariable-adjusted logistic regression model, this analysis tested the volume of plasma expansion over the first 48 h of hospitalization as a predictor of favorable outcome, defined as either a modified Rankin Scale score of 0 or 1 or a NIHSS score of 0 or 1 at 90 days. This model included all study patients, irrespective of albumin or isotonic saline treatment.

RESULTS

Patients that received higher volumes of plasma expansion more frequently had large vessel ischemic stroke and higher NIHSS scores. The multivariable-adjusted model revealed that there was decreased odds of a favorable outcome for every 250 ml additional volume plasma expansion over the first 48 h (OR 0.91, 95 % CI, 0.88-0.94).

CONCLUSIONS

The present study demonstrates an association between greater volume of plasma expansion and worse neurological recovery.

Elevated Blood Urea Nitrogen/Creatinine Ratio Is Associated with Venous Thromboembolism in Patients with Acute Ischemic Stroke

Objective

Although venous thromboembolism (VTE) is frequently related to dehydration, the impact of dehydration on VTE in acute ischemic stroke (AIS) is not clear. This study investigated whether dehydration, as measured by blood urea nitrogen (BUN)/creatinine (Cr) ratio, influences the occurrence of VTE in patients with AIS.

Methods

This is a retrospective study of patients with AIS between January 2012 and December 2013. Patients with newly diagnosed AIS who experienced prolonged hospitalization for at least 4 weeks were included in this study.

Results

Of 182 patients included in this study, 17 (9.3%) suffered VTE during the follow-up period; in two cases, VTE was accompanied by deep vein thrombosis and pulmonary embolism. Patients with VTE were more frequently female and had higher National Institutes of Health Stroke Scale (NIHSS) score, more lower limb weakness, and elevated blood urea nitrogen BUN/Cr ratio on admission. In a multivariate analysis, BUN/Cr ratio >15 (odds ratio [OR] 8.75) and severe lower limb weakness (OR 4.38) were independent risk factors for VTE.

Conclusion

Dehydration on admission in cases of AIS might be a significant independent risk factor for VTE.

A randomized controlled study of intravenous fluid in acute ischemic stroke

OBJECTIVE

To compare the outcome of patients with acute ischemic stroke who received or did not receive intravenous fluid.

PATIENTS AND METHODS

This study was a prospective, multicenter, randomized, open-label trial with blinded outcome assessment. We enrolled acute ischemic stroke patients without dehydration aged between 18 and 85 years with NIH Stroke Scale score (NIHSS) score from 1 to 18 who presented within 72h after onset. Patients were randomly assigned to receive 0.9% NaCl solution 100ml/h for 3days or no intravenous fluid.

RESULTS

On the interim unblinded analysis of the safety data, significant excess early neurological deterioration was observed among patients in the non-intravenous fluid group. Therefore, the study was prematurely discontinued after enrollment of 120 patients, mean age 60 years, 56.6% male. Early neurological deterioration (increased NIHSS ≥3 over 72h) not of metabolic or hemorrhagic origin was observed in 15% of the non-IV fluid group and 3.3% of the IV fluid group (p=0.02). Predictors of neurological deterioration were higher NIHSS score, higher plasma glucose, and increased pulse rate. There was no difference in the primary efficacy outcome, NIHSS≤4 at day 7, 83.3% vs 86.7%, p=0.61 or secondary efficacy outcomes.

CONCLUSION

Administration of 0.9% NaCl 100ml/h for 72h in patients with acute ischemic stroke is safe and may be associated with a reduced risk of neurological deterioration. These study findings support the use of intravenous fluid in acute ischemic stroke patients with NIHSS less than 18 who have no contraindications.

[Causal relationships in stroke and kidney injury]

AIM

To assess the frequency, severity, and causes of acute kidney injury (AKI) in patients with stroke.

SUBJECTS AND METHODS

272 patients (143 men and 129 women) (mean age, 66.7±11.6 years) with stroke were examined. The 2008 European Stroke Organization (ESO) guidelines were used to diagnose stroke, to determine indications for and contraindications to thrombolytic therapy, and to evaluate its efficiency. Hemorrhagic and ischemic strokes (HS and IS) were diagnosed in 52 (19%) and 220 (81%) patients, respectively. AKI was diagnosed and classified according to the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

RESULTS

AKI was diagnosed in 89 (33%) patients: 19 (36.5%) with HS and 70 (31.8%) with IS. The relative risk of death in patients with AKI-associated stroke was 2.6 (95% confidence interval (CI) 1.6-4.0). A poor outcome (the combined endpoint of death or Rankin scale scores of 4-5) was noted in 56 (62.9%) patients with AKI and in 70 (38.2 %) without AKI (χ2=14.6; p=0.0002). The relative risk of a poor outcome in patients with AKI-associated with stroke was 1.64 (95% CI 1.3-2.0). Forty-five (50.6%) patients with stroke developed AKI in the prehospital period.

CONCLUSION

AKI complicates stroke in every three patients and increases death rates. 50% of cases develop AKI in the prehospital period due to the common causes of stroke and AKI.

Urine-Specific Gravity-Based Hydration Prevents Stroke in Evolution in Patients with Acute Ischemic Stroke

BACKGROUND

Early neurological deterioration after ischemic stroke (stroke-in-evolution [SIE]) is associated with poorer outcomes. Previous studies have demonstrated a link between hydration status and the development of SIE. In this study, we tested the hypothesis that rehydration therapy, administered on the basis of urine-specific gravity (USG) findings, might reduce the development of SIE.

METHODS

We conducted a single-arm prospective study of patients with acute ischemic stroke with historical controls. For the study group, a USG higher than 1.010 was taken as an indication for rehydration. Control group patients were rehydrated without referring to USG. An increase in National Institutes of Health Stroke Scale (NIHSS) score of 4 or higher within 3 days was defined as having SIE.

RESULTS

A total of 445 patients were analyzed, 167 in the study group and 278 in the control group. The proportion of patients who developed SIE was numerically, but not significantly, lower in the study group (5.9%; 10 of 167) compared with the control group (11.5%; 32 of 278). Among patients with a USG higher than 1.010 at admission, the SIE rate was significantly reduced in the study group compared with the control group (6.1% versus 16.0%; P = .021), while the rate of SIE was similar in those with a USG of 1.010 or lower at admission. Multivariate logistic regression analysis confirmed that USG-based hydration was an independent factor associated with reducing SIE.

CONCLUSIONS

USG might be a convenient and useful method for guiding fluid therapy in patients with acute ischemic stroke. USG-based hydration reduced the incidence of SIE among patients with a USG higher than 1.010 at admission.

The influence of dehydration on the prognosis of acute ischemic stroke for patients treated with tissue plasminogen activator

Background

Many studies have determined that dehydration is an independent predictor of outcome after ischemic stroke (IS); however, none have determined if the use of thrombolytic therapy modifies the negative impact of poor hydration. To inform the stroke registry established at our institution, we conducted a retrospective study to determine if dehydration remains a negative prognostic factor after IS patients treated with tissue plasminogen activator (tPA).

Methods

Between 2007 and 2012, we recruited 382 subjects; 346 had data available and were divided into 2 groups on the basis of their blood urea nitrogen/creatinine (BUN/Cr) ratio. Dehydrated subjects had a BUN/Cr ratio ≥ 15; hydrated subjects had a BUN/Cr < 15. The primary outcome was impairment at discharge as graded by the Barthel Index (BI) and the modified Rankin Scale (mRS).

Results

The dehydration group had a greater mean age; more women; lower mean levels of hemoglobin, triglycerides, and sodium; and higher mean potassium and glucose levels. A favorable outcome as assessed by the mRS (≤2) was significantly less frequent among dehydrated subjects, but a favorable outcome by the BI (≥60) was not. Logistic regression and multivariate models confirmed that dehydration is an independent predictor of poor outcome by both the mRS and the BI; however, it was not predictive when patients were stratified by Trial of Org 10,172 in Acute Stroke Treatment subtype.

Conclusions

Our findings indicate that use of thrombolytic therapy does not eliminate the need to closely monitor hydration status in patients with IS.

Dehydration Status is Associated With More Severe Hemispatial Neglect After Stroke

BACKGROUND

Many stroke patients are clinically dehydrated at the time of hospital presentation, which could lead to an increase in blood viscosity and alteration in cerebral perfusion. Impaired cerebral perfusion can cause hemispheric dysfunction, which can be rapidly quantified with bedside tests of hemispatial neglect. We hypothesized that hospitalized patients with laboratory markers consistent with dehydration or a volume contracted state (VCS) would have more severe cerebral dysfunction defined by greater degree of neglect.

METHODS

Subjects were a consecutive series of right-handed patients with acute right hemispheric stroke admitted within the Johns Hopkins Health System. All participants had clinical syndrome and magnetic resonance imaging consistent with acute infarction. The primary definition of a VCS was a urea/creatinine ratio >15, with secondary definition including urine specific gravity over 1.010. Acute infarct volume was measured on magnetic resonance imaging. Neglect was evaluated using a standardized battery of bedside tests.

RESULTS

Of 201 patients meeting inclusion criteria, 131/201 (65%) had elevated BUN/creatinine ratios at admission. Approximately 61% (122/201) had some degree of neglect. Elevated BUN/creatinine ratio was associated with an increased odds of severe neglect in unadjusted models (OR=4.1; 95% CI, 1.2, 14.4), with loss of significance in adjusted models (OR=4.43; 95% CI, 0.99, 19.8) after adjustment for age, infarct volume, sex, and NIHSS score.

CONCLUSIONS

Our data suggest that patients who are in a VCS at the time of stroke may have more frequent and severe neglect, with attenuation of results after adjustment for factors related to stroke size and age. If proven clinically relevant, a formalized rehydration strategy based on objective lab markers may represent an opportunity for improvement in outcome with low-cost, broadly available treatment for acute stroke patients.

Non-Invasive Respiratory Impedance Enhances Cerebral Perfusion in Healthy Adults

Optimization of cerebral blood flow (CBF) is the cornerstone of clinical management in a number of neurologic diseases, most notably ischemic stroke. Intrathoracic pressure influences cardiac output and has the potential to impact CBF. Here, we aim to quantify cerebral hemodynamic changes in response to increased respiratory impedance (RI) using a non-invasive respiratory device. We measured cerebral perfusion under varying levels of RI (6 cm H₂O, 9 cm H₂O, and 12 cm H₂O) in 20 healthy volunteers. Simultaneous measurements of microvascular CBF and middle cerebral artery mean flow velocity (MFV), respectively, were performed with optical diffuse correlation spectroscopy and transcranial Doppler ultrasound. At a high level of RI, MFV increased by 6.4% compared to baseline (p = 0.004), but changes in cortical CBF were non-significant. In a multivariable linear regression model accounting for end-tidal CO₂, RI was associated with increases in both MFV (coefficient: 0.49, p < 0.001) and cortical CBF (coefficient: 0.13, p < 0.001), although the magnitude of the effect was small. Manipulating intrathoracic pressure via non-invasive RI was well tolerated and produced a small but measurable increase in cerebral perfusion in healthy individuals. Future studies in acute ischemic stroke patients with impaired cerebral autoregulation are warranted in order to assess whether RI is feasible as a novel non-invasive therapy for stroke.

Elevated blood viscosity is associated with cerebral small vessel disease in patients with acute ischemic stroke

BACKGROUND

Increased level of blood viscosity, which is one of the major factors that determine blood rheology, has been reported as a risk factor or predictor for cerebrovascular events. We investigated how blood viscosity is associated with acute stroke and chronic radiological manifestations of cerebral small vessel disease, and how blood viscosity changes after stroke.

METHODS

We prospectively enrolled consecutive patients with acute ischemic stroke. Whole blood viscosities at a low or high shear rate were measured using a scanning capillary tube viscometer, and were referred to as diastolic blood viscosity (DBV) and systolic blood viscosity (SBV), respectively. Correlations between blood viscosity and acute stroke etiology or chronic radiological manifestations of cerebral small vessel disease were investigated. The temporal profiles of blood viscosity at the onset of stroke and follow-up at 1 and 5 weeks were investigated.

RESULTS

Of the 127 patients admitted with acute ischemic stroke, 63 patients were included in the final analyses. DBV at the onset of stroke was significantly higher in small artery occlusion (SAO) stroke than in other stroke subtypes (p = 0.037). DBV showed a significant positive correlation with the number of chronic lacunes (r = 0.274, p = 0.030). The temporal profiles of DBV in SAO stroke showed a transient decrease due to the hydration therapy after 1 week and recurrent elevation at 5 week follow-up (p = 0.009).

CONCLUSIONS

Our study suggests that elevated DBV may play a role in the development of acute and chronic manifestations of cerebral small vessel disease. The recurring elevation of DBV in SAO stroke indicates that sufficient hydration and additional therapeutic interventions targeting blood viscosity may be needed in patients with SAO stroke.

Favorable outcome of blood urea nitrogen/creatinine-based hydration therapy 3 months after acute ischemic stroke

BACKGROUND

Dehydration is associated with acute ischemic stroke. However, the relationship between hydration therapy given during acute ischemic stroke and clinical outcomes remains unclear.

AIMS

We determined whether hydration therapy in patients with a blood urea nitrogen/creatinine (BUN/Cr) ratio of at least 15 improved clinical outcome.

METHODS

We conducted a nonblinded, phase II, single-arm, prospective study of patients with acute ischemic stroke and BUN/Cr ratio of at least 15 with historical controls. The hydration group received intravenous bolus (300-500 mL) saline followed by maintenance saline infusion (40-80 mL/h for the first 72 hours), whereas the control group received maintenance saline infusion (40-60 mL/h for the first 24 hours and 0-60 mL/h for 24-72 hours after stroke). The study end point was the percentage of patients with a favorable outcome defined as modified Rankin scale score of 2 or lower at 3 months after stroke.

RESULTS

A total of 237 patients were enrolled (hydration, n = 134; control, n = 103). The mean volume of saline infused within the first 72 hours was significantly larger (P < .001), and the rate of favorable outcome at 3 months after stroke was significantly higher (P = .016) in the hydration group than in the controls. Further analysis revealed that the difference was significant in the lacunar stroke subtype (P = .020) but not in the nonlacunar subtype.

CONCLUSIONS

Blood urea nitrogen/Cr ratio-based saline hydration therapy in patients with acute ischemic stroke significantly increased the rate of favorable clinical outcome with functional independence at 3 months after stroke.

Optimizing Outcomes for Mechanically Ventilated Patients in an Era of Endovascular Acute Ischemic Stroke Therapy

Endovascular mechanical thrombectomy is a new standard of care for acute ischemic stroke (AIS). The majority of these patients receive mechanical ventilation (MV), which has been associated with poor outcomes. The implication of this is significant, as most neurointerventionalists prefer general compared to local anesthesia during the procedure. Consequences of hemodynamic and respiratory perturbations during general anesthesia and MV are thought to contribute significantly to the poor outcomes that are encountered. In this review, we first describe the unique risks associated with MV in the specific context of AIS and then discuss evidence of brain goal-directed approaches that may mitigate these risks. These strategies include an individualized approach to hemodynamic parameters (eg, adherence to a minimum blood pressure goal and adequate volume resuscitation), respiratory parameters (eg, arterial carbon dioxide optimization), and the use of ventilator settings that optimize neurological outcomes (eg, arterial oxygen optimization).

Increased Blood Viscosity in Ischemic Stroke Patients with Small Artery Occlusion Measured by an Electromagnetic Spinning Sphere Viscometer

BACKGROUND AND PURPOSE

High blood viscosity causes blood stagnation and subsequent pathological thrombotic events, resulting in the development of ischemic stroke. We hypothesize that the contribution of blood viscosity may differ among ischemic stroke subtypes based on specific pathological conditions. We tried to verify this hypothesis by measuring blood viscosity in acute ischemic stroke patients using a newly developed electromagnetic spinning sphere (EMS) viscometer.

METHODS

Measurements in acute ischemic stroke patients were performed 4 times during admission and data were compared with those obtained from 100 healthy outpatient volunteers.

RESULTS

We enrolled 92 patients (cardioembolism: 25, large artery atherosclerosis: 42, and small artery occlusion [SAO]: 25) in this study. Comparisons of blood viscosity between the ischemic stroke subgroups and control group revealed that blood viscosity at the date of admission was significantly higher in the SAO group (5.37 ± 1.11 mPa⋅s) than in the control group (4.66 ± .72 mPa⋅s) (P < .01). Among all subtype groups showing a reduction in blood viscosity after 2 weeks, the SAO group showed the highest and most significant reduction, indicating that SAO patients had the most concentrated blood at the onset.

CONCLUSIONS

Blood viscosity was significantly increased in the SAO group at the date of admission, which indicated the contribution of dehydration to the onset of ischemic stroke. The importance of dehydration needs to be emphasized more in the pathogenesis of SAO. The clinical application of the EMS viscometer is promising for understanding and differentiating the pathogenesis of ischemic stroke.

Label-free and pH-sensitive colorimetric materials for the sensing of urea

This communication demonstrates a facile method for naked-eye detection of urea based on the structure color change of pH-sensitive photonic crystals. The insertion of urease provides excellent selectivity over other molecules. The detection of urea in different concentration ranges could be realized by changing the molar ratio between the functional monomer and cross-linker.

Effect of dehydration on the development of collaterals in acute middle cerebral artery occlusion

BACKGROUND AND PURPOSE

Recent large series studies have demonstrated that dehydration is common amongst stroke subjects and is associated with poor outcome. However, the effects of hydration status on the development of collaterals have never been discussed. In this study, the hypothesis that hydration status is an important factor for developing collaterals after acute middle cerebral artery (MCA) infarction was tested.

METHODS

Eighty-seven patients with acute infarction due to occlusion of the MCA were enrolled. Two collateral markers, posterior cerebral artery (PCA) laterality and fluid-attenuated inversion recovery hyperintense vessels (HVs) were assessed from magnetic resonance imaging. Dehydration status was defined by a nitrogen to creatinine ratio ≧ of 15. The associations between dehydration status and the development of collaterals were estimated.

RESULTS

Sixty-one of 87 patients (70.1%) were identified as dehydrated. The development of PCA laterality and HVs shows a significant difference between dehydrated and euhydrated patients. A serum nitrogen to creatinine ratio <15, diastolic blood pressure and the presence of a dense MCA on computed tomography were significantly associated with the development of PCA laterality. A serum nitrogen to creatinine ratio <15, the initial National Institutes of Health Stroke Scale score, the presence of a dense MCA and calcifications of the internal carotid artery on computed tomography were significantly associated with the development of HVs. Dehydration remained an independent negative predictor for the development of PCA laterality and HVs in the multivariate analysis.

CONCLUSIONS

Hydration status is associated with the development of collateral flow after acute MCA occlusion. This preliminary study provides an imaging clue that hydration status and early hydration therapy could be important for acute stroke management.

Preliminary Prospective Study to Assess the Effect of Early Blood Urea Nitrogen/Creatinine Ratio-Based Hydration Therapy on Poststroke Infection Rate and Length of Stay in Acute Ischemic Stroke

BACKGROUND

This study aimed to determine whether blood urea nitrogen (BUN)/creatinine (Cr)-based hydration therapy can decrease the rate of poststroke infection and length of stay (LOS) in the neurology ward.

METHODS

This was a nonblinded, phase II single-arm prospective study with a historical control group of patients with acute ischemic stroke and a BUN/Cr ratio of 15 or higher. The study group (n = 134) received an intravenous saline bolus (300-500 mL) followed by maintenance saline (40-80 mL/hour) for the first 72 hours. The control group (n = 103) received maintenance saline infusions (40-60 mL/hour for the first 24 hours and 0-60 mL/hour for the next 24-72 hours).

RESULTS

The hydration group had a significantly lower poststroke infection rate than did the control group (7.5% versus 17.5%, P = .018) and significantly shorter LOS in the neurology ward (13.5 ± 11.6 versus 19.6 ± 14.6 days, P < .01). With regard to adverse events, two patients in each group had cerebral edema.

CONCLUSIONS

The findings suggest that the BUN/Cr ratio needs to be corrected in a timely manner in patients with acute ischemic stroke. Providing prompt saline hydration therapy based on the daily BUN/Cr ratio might decrease the poststroke infection rate and shorten LOS.

Analysis of blood trace elements and biochemical indexes levels in severe craniocerebral trauma adults with Glasgow Coma Scale and injury severity score

We aimed to investigate the correlation between the Glasgow Coma Scale (GCS), the injury severity score (ISS) and serum levels of trace elements (TE) in severe trauma patients to analyze alteration of the levels of trace elements and serum biochemical indexes in the period of admission from 126 adult cases of severe brain trauma with traffic accidents. Multi-trace elements for patients in the trauma-TE groups were used. The results indicated that all patients presented an acute trace elements deficiency syndrome (ATEDs) after severe trauma, and the correlation between ISS and serum levels of Fe, Zn, and Mg was significant. Compared to the normal control group, levels of the trace elements in serum were significantly decreased after trauma, suggesting that enhancement of immunity to infection and multiple organ failure (MOF) via the monitoring and supplement of trace elements will be a good strategy to severe traumatic patients in clinics.

CT-pro-AVP as a tool for assessment of intravascular volume depletion in severe hyponatremia

BACKGROUND

Assessment of volume status is essential to best manage hyponatremic patients but is not always accurate in clinical practice. The aim of this study was to evaluate the reliability of C-terminal portion of pro-arginine-vasopressin (CT-pro-AVP), a surrogate biomarker of vasopressin release, in assessing intravascular volume (IVV) depletion in hypoosmolar hyponatremic patients.

METHODS

Plasma CT-pro-AVP and urea-to-creatinine ratio (Ur/Cr) were performed in 131 hospitalized patients presenting chronic severe hypoosmolar hyponatremia. At hospital discharge, their IVV was evaluated regardless of CT-pro-AVP concentrations. All patients were then classified as decreased or as normal/expanded IVV group.

RESULTS

Plasma CT-pro-AVP levels were higher in patients with decreased IVV (34.6 vs. 11.3 pmol/L, p<0.001) and exhibited a reliable performance for assessment of decreased IVV (ROC AUC at 0.717 [95% CI 0.629-0.805]). The combination of CT-pro-AVP and Ur/Cr resulted in an improved ROC AUC up to 0.787 (95% CI 0.709-0.866).

CONCLUSIONS

Our findings support the hypothesis that CT-pro-AVP plasma level may reflect IVV and would be a tool for its assessment. This performance has been magnified by its combination with Ur/Cr. A dual-marker strategy may help clinicians to optimize the management of severe hyponatremia especially in case of confusing clinical presentations.

Dehydration is an independent predictor of discharge outcome and admission cost in acute ischaemic stroke

BACKGROUND AND PURPOSE

Our aim was to investigate the influence of admission dehydration on the discharge outcome in acute ischaemic and hemorrhagic stroke.

METHODS

Between January 2009 and December 2011, 4311 ischaemic and 1371 hemorrhagic stroke patients from the stroke registry of Chang Gung healthcare system were analyzed. The eligible patients were identified according to inclusion/exclusion criteria. In total, 2570 acute ischaemic and 573 acute hemorrhagic stroke patients were finally recruited. According to the blood urea nitrogen (BUN) to creatinine (Cr) ratio (BUN/Cr), these patients were divided into dehydrated (BUN/Cr ≥ 15) and non-dehydrated (BUN/Cr < 15) groups. Demographics, admission costs and discharge outcomes including modified Rankin scale (mRS) and Barthel index (BI) were examined. Data were analyzed using multivariate analysis of two-stage least squares including logistic and linear regression.

RESULTS

Acute ischaemic stroke with admission dehydration had higher infection rates (P = 0.006), worse discharge BI (62.8 ± 37.4 vs. 73.4 ± 32.4, P < 0.001, adjusted P < 0.001), worse mRS (2.7 ± 1.6 vs. 2.3 ± 1.5, P < 0.001, adjusted P = 0.009) and higher admission costs (2470.8 ± 3160.8 vs. 1901.2 ± 2046.8 US dollars, P < 0.001, adjusted P = 0.013) than those without dehydration. However, acute hemorrhagic stroke with or without admission dehydration showd no difference in admission costs (P = 0.618) and discharge outcomes (BI, P = 0.058; mRS, P = 0.058).

CONCLUSION

Admission dehydration is associated with worse discharge outcomes and higher admission costs in acute ischaemic stroke but not in hemorrhagic stroke.