Inflammation, negative nitrogen balance, and outcome after aneurysmal subarachnoid hemorrhage

Metabolic support challenges with obesity during critical illness

Adiposity-based chronic disease, critical illness, and nutrition therapy increase the risk for overfeeding and worsened nutritional and clinical outcomes. Hypocaloric, high-protein nutrition therapy provides critically ill obese patients the opportunity to achieve net protein anabolism with a reduced risk for overfeeding-related complications. The intent of this review is to discuss the impact of obesity on clinical outcomes, describe the consequences of obesity that increase complications associated with nutrition therapy, provide the framework to develop a hypocaloric, high-protein regimen, review the scientific evidence to support this mode of therapy, and discuss its limitations. Practical suggestions for patient monitoring are also provided.

Neuroinflammation as a Target for Intervention in Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a sub-type of hemorrhagic stroke associated with the highest rates of mortality and long-term neurological disabilities. Despite the improvement in the management of SAH patients and the reduction in case fatality in the last decades, disability and mortality remain high in this population. Brain injury can occur immediately and in the first days after SAH. This early brain injury can be due to physical effects on the brain such as increased intracranial pressure, herniations, intracerebral, intraventricular hemorrhage, and hydrocephalus. After the first 3 days, angiographic cerebral vasospasm (ACV) is a common neurological complication that in severe cases can lead to delayed cerebral ischemia and cerebral infarction. Consequently, the prevention and treatment of ACV continue to be a major goal. However, most treatments for ACV are vasodilators since ACV is due to arterial vasoconstriction. Other targets also have included those directed at the underlying biochemical mechanisms of brain injury such as inflammation and either independently or as a consequence, cerebral microthrombosis, cortical spreading ischemia, blood–brain barrier breakdown, and cerebral ischemia. Unfortunately, no pharmacologic treatment directed at these processes has yet shown efficacy in SAH. Enteral nimodipine and the endovascular treatment of the culprit aneurysm, remain the only treatment options supported by evidence from randomized clinical trials to improve patients’ outcome. Currently, there is no intervention directly developed and approved to target neuroinflammation after SAH. The goal of this review is to provide an overview on anti-inflammatory drugs tested after aneurysmal SAH.

Systemic metabolism and energy consumption after microsurgical clipping and endovascular coiling for aneurysmal subarachnoid hemorrhage

BACKGROUND

The postoperative metabolic states of subarachnoid hemorrhage (SAH) patients were investigated using indirect calorimetry (IDC) and various nutritional evaluations to establish any difference in perioperative metabolic and nutritional states between microsurgical and endovascular treatment.

METHODS

This study included 30 acute aneurysmal SAH patients with ruptured intracranial aneurysms treated by surgical clipping (n = 16) or coil embolization (n = 14) at a single institute. The resting energy expenditure (REE) and respiratory quotient were measured using IDC on days 1, 4, 7, 10, 14, and 17-21 after the operation. Various blood tests, including C-reactive protein (CRP) and prealbumin, were evaluated on the same days.

RESULTS

The clipping group showed a significant increase in REE/basal energy expenditure (BEE) compared with the coiling group on days 1 and 4 (p = 0.04 and 0.03, respectively). No significant differences were found on days 7, 10, 14, and 17-21. The mean REE/BEE on days 1-14 and 1-21 showed no significant differences between the groups with repeated measures analysis of variance. The clipping group showed a significant decrease of prealbumin on day 4 and significant increase in CRP on days 1, 4, and 7.

CONCLUSIONS

The clipping group was in the hypermetabolic state compared with the coiling group during the very early postoperative period. However, the difference associated with the treatment modality was relatively small compared to the effects of the SAH and of the sequelae.

Circular RNA hsa_circ_0021001 in peripheral blood: a potential novel biomarker in the screening of intracranial aneurysm

Circular RNAs (circRNAs) in the peripheral blood have been reported to be associated with cancer. However, there are few studies about circRNAs in intracranial aneurysms (IA). The purpose of the current study was to investigate the characteristic expression of circular RNA hsa_circ_0021001 in the peripheral blood of patients with intracranial aneurysms and its potential as a diagnostic biomarker for IA. In this study, a cohort of 223 cases of IA patients who were admitted in the department of neurosurgery in the First People’s Hospital of Wenling from January 2009 to July 2012 were collected as the experimental group, and 131 healthy volunteers over the same period served as the control group. Peripheral blood of each subject in both groups was collected on an empty stomach. The expression of hsa_circ_0021001 in peripheral blood was detected by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and the difference was analyzed by paired t-test. The effectiveness of hsa_circ_0021001 in the diagnosis of IA was assessed by ROC curve. Multivariate Cox proportional hazards regression analysis was used to analyze the prognosis. Hsa_circ_0021001 level in the peripheral blood of IA patients was relatively lower than that in the control group (P=0.002). The area under ROC (AUC) was 0.87, indicating that hsa_circ_0021001 was highly effective in the diagnosis of IA. In addition, hsa_circ_0021001 expression was correlated with aneurysm rupture, Hunt, Hess level, and timing of surgery (P= 0.041, 0.013, and 0.001, respectively). Patients with high expression of hsa_circ_0021001 had longer disease-free survival (DFS) and overall survival (OS) (P < 0.05). We found for the first time that hsa_circ_0021001 decreased significantly in the peripheral blood of IA patients, which suggested that hsa_circ_0021001 might be used as a potential novel marker for the diagnosis of IA.

Early Hypoalbuminemia is an Independent Predictor of Mortality in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Hypoalbuminemia has been identified as a predictor of morbidity and mortality in critically ill patients. There is very little data on the significance and the prognostic value of hypoalbuminemia in patients with aneurysmal subarachnoid hemorrhage (aSAH). This study analyzed the impact of hypoalbuminemia on patient presentation, complications, and outcomes.

METHODS

Records of patients admitted with aSAH were examined. Data on baseline characteristics, prevalence of delayed cerebral ischemia, and discharge outcomes were collected. Multivariable logistic regression analysis was performed to assess for associations.

RESULTS

One-hundred and forty-two patients comprised the study cohort (mean age 54.6 ± 13.4), among which 45 (31.5 %) presented with hypoalbuminemia. No difference in baseline characteristics was noted between patients with hypoalbuminemia and those with normal serum albumin. The overall hospital mortality rate was significantly higher in patients with hypoalbuminemia, compared to those with normal albumin (28.9 % vs. 11.3 %; p = 0.04). Hypoalbuminemia was neither associated with delayed cerebral ischemia nor disability at discharge, but independently associated with in-hospital death (odds ratio: 4.26, 95 % confidence interval: 1.09-16.68; p = 0.04).

CONCLUSION

In patients with aSAH, early hypoalbuminemia is an independent predictor of hospital mortality but not disability at discharge.

Serum albumin level in spontaneous subarachnoid haemorrhage: More than a mere nutritional marker!

BACKGROUND

The role of nutritional markers on outcome following subarachnoid hemorrhage (SAH) has been scarcely described.

METHODS

This is a prospective study of 273 patients with SAH, in which haemoglobin, serum protein and albumin were measured within 24 hours and again at one week following ictus, and analysed with respect to other variables. New neurologic deficits (NND), infarct, mortality and Glasgow outcome scale (GOS) at 3 months were assessed.

RESULTS

The values of haemoglobin, total protein and albumin showed significant (p < .001) decline over the first week of SAH. Patients who developed NND had significantly lower serum albumin levels at admission compared to others (median 3.6 vs 3.9 g/dL, p < .001). Patients having lower albumin (≤3.5 gm/dL) levels at admission had significantly higher rates of NND (52% vs 20%), infarct (35% vs 23%), mortality (28% vs 16%) and unfavourable GOS (38% vs 25%). Hunt & Hess (H&H) grade and Fisher grade also affected all the outcome parameters significantly. Percentage decrease in albumin levels at one week following ictus significantly affected mortality and unfavourable GOS. On multivariate analyses, Fisher grade and lower admission albumin levels had significant impact on NND, while percentage decrease in albumin levels had significant impact on mortality and unfavourable GOS, independent of other nutritional markers and known prognostic variables.

CONCLUSIONS

Serum albumin levels following SAH can be useful to predict development of NND, while its further weekly decrease correlates independently with unfavourable outcome at 3 months. Albumin assessment being readily available may serve as more than a mere nutritional parameter in SAH.

The diagnostic value of the neutrophil-lymphocyte ratio in distinguishing between subarachnoid hemorrhage and migraine

OBJECTIVE

Migraine and subarachnoid hemorrhage (SAH) patients present to emergency departments with the similar symptoms as headache, nausea, and vomiting. This study investigated whether the neutrophil-lymphocyte ratio (NLR) could distinguish patients with SAH from those with migraine.

METHODS

This retrospective study was performed after research ethics committee approval. Data were gathered from the ED and neurology clinics of a university hospital between January 2015 and January 2016, from patients with symptoms of headache (primarily), nausea and vomiting. One hundred and twenty one with SAH, 123 patients with migraine and 987 with other primary headache syndromes were considered. Neutrophil-lymphocyte ratios (NLR-1) were compared between groups on admission. In SAH patients NLR taken on the 24th-30th hour of admission (NLR-2) was compared to admission NLR.

RESULTS

NLR values, showed that the median NLR values of SAH patients were significantly higher than migraine and other headaches group values (p<0.001; p<0.001). There was no statistically significant difference between the NLR values of the migraine and control groups (p>0.05). An NLR cut-off value of 4.02 produced 85.95% sensitivity, 97.46% specificity, a 33.79 positive likelihood ratio (LR+), and a 0.14 negative likelihood ratio (LR-). A statistically significant increase was observed in median NLR-2 values compared to median NLR-1 values in SAH patients (p<0.001).

CONCLUSION

In this retrospective analysis, NLR distinguished patients with SAH from those with migraine. Presence of SAH should be evaluated from discharged and readmitted patients (with headache symptoms) when an increase in NLR between initial and readmission levels is observed.

Serum microRNAs are non-invasive biomarkers for the presence and progression of subarachnoid haemorrhage

miRNAs are important regulators of translation and have been associated with the pathogenesis of a number of cardiovascular diseases including stroke and may be possible prognostic biomarkers. The purpose of the present study was to determine the expression levels of miRNAs in the sera of subarachnoid haemorrhage (SAH) patients and to evaluate their relationships with the severity and clinical outcome of SAH. Serum samples on day 3 after the onset of SAH were subjected to microarray analysis with Exqion miRCURY^TM LNA array and quantitative PCR analysis. Serum samples from SAH patients (n=60) and healthy controls (n=10) were subjected to quantitative PCR analysis. The severities and clinical outcomes of the SAH patients were evaluated with the WFNS grade and the Modified Rankin Scale (mRS). Three miRNAs, miR-502-5p, miR-1297 and miR-4320 were significantly up-regulated in the sera of SAH patients when compared with the healthy controls. The serum miR-502-5p and miR-1297 levels were significantly higher in the patients with severe SAH and a poor outcome than in those with mild SAH and a good outcome (P<0.05). The areas under the receiver operating characteristic (ROC) curves (AUCs) of miR-502-5p, miR-1297 and miR-4320 to distinguish the SAH patients from the healthy controls were 0.958 (P<0.001), 0.950 (P<0.001) and 0.843 (P<0.001) respectively. Taken together, these results indicate that miR-502-5p and miR-1297 are potentially valuable indicators of the diagnosis, severity and prognosis of SAH, and miR-4320 was a potentially valuable indicator of the diagnosis of SAH.

The Pathophysiology of Delayed Cerebral Ischemia

Subarachnoid hemorrhage (SAH) affects 30,000 people in the Unites States alone each year. Delayed cerebral ischemia occurs days after subarachnoid hemorrhage and represents a potentially treatable cause of morbidity for approximately one-third of those who survive the initial hemorrhage. While vasospasm has been traditionally linked to the development of cerebral ischemia several days after subarachnoid hemorrhage, emerging evidence reveals that delayed cerebral ischemia is part of a much more complicated post-subarachnoid hemorrhage syndrome. The development of delayed cerebral ischemia involves early arteriolar vasospasm with microthrombosis, perfusion mismatch and neurovascular uncoupling, spreading depolarizations, and inflammatory responses that begin at the time of the hemorrhage and evolve over time, culminating in cortical infarction. Large-vessel vasospasm is likely a late contributor to ongoing injury, and effective treatment for delayed cerebral ischemia will require improved detection of critical early pathophysiologic changes as well as therapeutic options that target multiple related pathways.

D-dimer may predict poor outcomes in patients with aneurysmal subarachnoid hemorrhage: a retrospective study

Serum biomarkers may play a reliable role in predicting the outcomes of patients with aneurysmal subarachnoid hemorrhage. This study retrospectively analyzed the relationship between serum biomarkers on admission and outcomes in patients with aneurysmal subarachnoid hemorrhage. We recruited 146 patients with aneurysmal subarachnoid hemorrhage who were treated in Renmin Hospital of Wuhan University of China between 1 May 2014 and 30 March 2016. There were 57 males and 89 females included and average age of included patients was 57.03 years old. Serum samples were taken immediately on admission (within 48 hours after initial hemorrhage) and the levels of serum biomarkers were detected. Baseline information, complications, and outcomes at 6 months were recorded. Univariate and multivariate logistic regression analyses were used to explore the relationship between biomarkers and clinical outcomes. Receiver operating characteristic curves were obtained to investigate the possibility of the biomarkers predicting prognosis. Of the 146 patients, 102 patients achieved good outcomes and 44 patients had poor outcomes. Univariate and multivariate analyses showed that high World Federation of Neurosurgical Societies grade, high serum D-dimer levels, and high neurological complications were significantly associated with poor outcomes. Receiver operating characteristic curves verified that D-dimer levels were associated with poor outcomes. D-dimer levels strongly correlated with neurological complications. In conclusion, we suggest that D-dimer levels are a good independent prognostic factor for poor outcomes in patients with aneurysmal subarachnoid hemorrhage.

SIRT3 Expression Decreases with Reactive Oxygen Species Generation in Rat Cortical Neurons during Early Brain Injury Induced by Experimental Subarachnoid Hemorrhage

Sirtuin3 (SIRT3) is an important protein deacetylase which predominantly presents in mitochondria and exhibits broad bioactivities including regulating energy metabolism and counteracting inflammatory effect. Since inflammatory cascade was proved to be critical for pathological damage following subarachnoid hemorrhage (SAH), we investigated the overall expression and cell-specific distribution of SIRT3 in the cerebral cortex of Sprague-Dawley rats with experimental SAH induced by internal carotid perforation. Results suggested that SIRT3 was expressed abundantly in neurons and endothelia but rarely in gliocytes in normal cerebral cortex. After experimental SAH, mRNA and protein expressions of SIRT3 decreased significantly as early as 8 hours and dropped to the minimum value at 24 h after SAH. By contrast, SOD2 expression increased slowly as early as 12 hours after experimental SAH, rose up sharply at the following 12 hours, and then was maintained at a higher level. In conclusion, attenuated SIRT3 expression in cortical neurons was associated closely with enhanced reactive oxygen species generation and cellular apoptosis, implying that SIRT3 might play an important neuroprotective role during early brain injury following SAH.

Association of nosocomial infections with delayed cerebral ischemia in aneurysmal subarachnoid hemorrhage

OBJECTIVE

Delayed cerebral ischemia (DCI) is a recognized complication of aneurysmal subarachnoid hemorrhage (aSAH) that contributes to poor outcome. This study seeks to determine the effect of nosocomial infection on the incidence of DCI and patient outcome.

METHODS

An exploratory analysis was performed on 156 patients with aSAH enrolled in the Cerebral Aneurysm Renin Angiotensin System study. Clinical and radiographic data were analyzed with univariate analysis to detect risk factors for the development of DCI and poor outcome. Multivariate logistic regression was performed to identify independent predictors of DCI.

RESULTS

One hundred fifty-three patients with aSAH were included. DCI was identified in 32 patients (20.9%). Nosocomial infection (odds ratio [OR] 3.5, 95% confidence interval [CI] 1.09–11.2, p = 0.04), ventriculitis (OR 25.3, 95% CI 1.39–458.7, p = 0.03), aneurysm re-rupture (OR 7.55, 95% CI 1.02–55.7, p = 0.05), and clinical vasospasm (OR 43.4, 95% CI 13.1–143.4, p < 0.01) were independently associated with the development of DCI. Diagnosis of nosocomial infection preceded the diagnosis of DCI in 15 (71.4%) of 21 patients. Patients diagnosed with nosocomial infection experienced significantly worse outcomes as measured by the modified Rankin Scale score at discharge and 1 year (p < 0.01 and p = 0.03, respectively).

CONCLUSIONS

Nosocomial infection is independently associated with DCI. This association is hypothesized to be partly causative through the exacerbation of systemic inflammation leading to thrombosis and subsequent ischemia.

Prognostic value of plasma galectin-3 levels after aneurysmal subarachnoid hemorrhage

BACKGROUND

Inflammatory responses are correlated with secondary brain injury after aneurysmal subarachnoid hemorrhage (aSAH). Galectin-3 (Gal-3) is a novel biomarker reflecting inflammation status, and its elevated circulating levels are associated with poor prognosis of some inflammatory diseases. The aim of this study was to evaluate the relationship between Gal-3 plasma levels and prognosis in a group of aSAH patients.

MATERIALS AND METHODS

We assessed plasma Gal-3 levels in 120 patients and 120 healthy individuals. 6-month clinical outcomes included mortality and unfavorable outcome (Glasgow Outcome Scale score of 1-3). Associations of plasma Gal-3 levels with clinical outcomes were investigated using multivariate analysis.

RESULTS

Patients showed significantly higher Gal-3 levels as compared to controls. Circulating Gal-3 was significantly and independently associated with 6-month clinical outcomes in the logistic regression analysis. Moreover, we observed a significant correlation between circulating Gal-3 and World Federation of Neurological Surgeons scores and modified Fisher scores. Furthermore, Gal-3 possessed high area under receiver operating characteristic curve for prognostic assessment.

CONCLUSION

Our findings indicate the associations between Gal-3 levels and the severity and poor prognosis following aSAH. This suggests the possible role of Gal-3 in the prognostic prediction after aSAH.

The change of plasma pituitary adenylate cyclase-activating polypeptide levels after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Elevated circulating pituitary adenylate cyclase-activating polypeptide (PACAP) levels have been demonstrated to be associated with clinical outcomes of severe traumatic brain injury. The current study aimed to confirm whether elevated plasma PACAP levels are predictive of clinical outcomes of aneurysmal subarachnoid hemorrhage (aSAH).

MATERIALS AND METHODS

One hundred and eighteen aSAH patients and 118 controls were recruited. Plasma PACAP concentrations were determined using enzyme-linked immunosorbent assay. Patients were followed up until death or completion of 6 months after aSAH. An unfavorable outcome was defined as Glasgow Outcome Scale score of 1-3.

RESULTS

The admission PACAP levels were significantly elevated in all patients (296.6 ± 119.7 pg/ml) compared with controls (77.1 ± 17.9 pg/ml, P < 0.001). Plasma PACAP levels were independently associated with clinical severity indicated by World Federation of Neurological Surgeons (WFNS) score (t = 4.745, P < 0.001) and Fisher score (t = 4.239, P < 0.001) using a multivariate linear regression. PACAP was identified as an independent predictor for 6-month mortality [odds ratio (OR), 1.014; 95% confidence interval (CI), 1.005-1.030; P < 0.001] and 6-month unfavorable outcome (OR, 1.012; 95% CI, 1.006-1.028; P < 0.001) and 6-month overall survival (hazard ratio, 1.016; 95% CI, 1.008-1.023; P < 0.001) using a binary logistic regression analysis and a Cox's proportional hazard analysis, respectively. PACAP had similar predictive values compared with WFNS score and Fisher score according to the receiver operating characteristic curve analysis.

CONCLUSIONS

Higher plasma PACAP levels are associated with clinical severity and long-term prognosis of aSAH patients, and PACAP has potential to be a good prognostic biomarker of aSAH.

Increased Resting Energy Expenditure after Endovascular Coiling for Subarachnoid Hemorrhage

BACKGROUND

Appropriate nutritional care from the acute stage is essential for improved functional outcomes and reduced mortality in patients with subarachnoid hemorrhage (SAH). Although endovascular coiling is increasingly being used as an alternative to neurosurgical clipping and craniotomy for ruptured aneurysms, the resting energy expenditure (REE) of patients treated with this new technique has not been systemically evaluated.

METHODS

We measured REE values by indirect calorimetry in 12 SAH patients treated with endovascular coiling. We averaged the REE measurements obtained on days 1 and 7 after endovascular coiling, and then we statistically compared the mean REE values with those in 30 patients with acute cerebral infarction (ACI) by the Wilcoxon rank-sum test (P <.05). Next, we calculated the ratio of measured REE values to the values estimated using the Harris-Benedict equation to adjust for demographic differences in sex, weight, height, and age between the groups.

RESULTS

The ratios were significantly higher in SAH patients (median value, 1.12; interquartile range, 1.05-1.23) than in ACI patients (median value, 1.02; interquartile range, .97-1.09).

CONCLUSIONS

Because endovascular coiling is less invasive than neurosurgical clipping, the observed increase in REE was attributed to metabolic changes after SAH. To provide optimal nutritional care to SAH patients from the acute stage, clinicians should be aware of this change in REE.