Predictors of extraventricular drain-associated bacterial ventriculitis.

PURPOSE: Bacterial ventriculitis (BV) may develop in patients requiring external ventricular drains (EVDs). The purpose of this study was to determine predictors of EVD-associated BV onset. MATERIALS AND METHODS: A retrospective review of Duke University Hospital patients with EVD device placement between January 2005 and May 2010 was conducted. Subject data were captured for predefined variables. Outcomes included in-hospital mortality, length of stay, and neurologic status at discharge. RESULTS: In 410 subjects with 420 EVDs, the BV rate was 10.2%. Univariate analysis indicated that age, sex, positive blood culture, duration of EVD placement, and the number of cerebrospinal fluid (CSF) samples taken were associated with BV. Of these, the number of CSF samples and sex retained significance in multivariable modeling (female: odds ratio, 0.47 [confidence interval, 0.23-0.97]; CSF samples: odds ratio, 1.08 [confidence interval 1.01-1.17]; P = .04; c index = 0.69). In this model, each CSF sample taken expanded the likelihood of BV by 8.3%. The most common pathogens were Staphylococcus or proprioniobacter (n = 26). Bacterial ventriculitis was associated with an increase in hospital length of stay (33 ± 22.9 days vs 24.6 ± 20.4 days; P = .04) but not mortality. CONCLUSION: An association exists between CSF sampling frequency and the development of EVD-associated BV. Larger prospective studies should be aimed at identifying causal relationships between these variables.

Predictors of late neurological deterioration after spontaneous intracerebral hemorrhage.

BACKGROUND: Although intracerebral hemorrhage (ICH) is a common form of cerebrovascular disease, little is known about factors leading to neurological deterioration occurring beyond 48 h after hematoma formation. The purpose of this study was to characterize the incidence, consequences, and associative factors of late neurological deterioration (LND) in patients with spontaneous ICH. METHODS: Using the Duke University Hospital Neuroscience Intensive Care Unit database from July 2007 to June 2012, a cohort of 149 consecutive patients with spontaneous supratentorial ICH met criteria for analysis. LND was defined as a decrease of two or more points in Glasgow Coma Scale score or death during the period from 48 h to 1 week after ICH symptom onset. Unfavorable outcome was defined as a modified Rankin Scale score of >2 at discharge. RESULTS: Forty-three subjects (28.9 %) developed LND. Logistic regression models revealed hematoma volume (OR = 1.017, 95 % CI 1.003-1.032, p = 0.019), intraventricular hemorrhage (OR = 2.519, 95 % CI 1.142-5.554, p = 0.022) and serum glucose on admission (OR = 2.614, 95 % CI 1.146-5.965, p = 0.022) as independent predictors of LND. After adjusting for ICH score, LND was independently associated with unfavorable outcome (OR = 4.000, 95 % CI 1.280-12.500, p = 0.017). In 65 subjects with follow-up computed tomography images, an increase in midline shift, as a surrogate for cerebral edema, was independently associated with LND (OR = 3.822, 95 % CI 1.157-12.622, p = 0.028). CONCLUSIONS: LND is a common phenomenon in patients with ICH; further, LND appears to affect outcome. Independent predictors of LND include hematoma volume, intraventricular hemorrhage, and blood glucose on admission. Progression of perihematomal edema may be one mechanism for LND.

S-nitrosylation therapy to improve oxygen delivery of banked blood.

From the perspectives of disease transmission and sterility maintenance, the world's blood supplies are generally safe. However, in multiple clinical settings, red blood cell (RBC) transfusions are associated with adverse cardiovascular events and multiorgan injury. Because ∼85 million units of blood are administered worldwide each year, transfusion-related morbidity and mortality is a major public health concern. Blood undergoes multiple biochemical changes during storage, but the relevance of these changes to unfavorable outcomes is unclear. Banked blood shows reduced levels of S-nitrosohemoglobin (SNO-Hb), which in turn impairs the ability of stored RBCs to effect hypoxic vasodilation. We therefore reasoned that transfusion of SNO-Hb-deficient blood may exacerbate, rather than correct, impairments in tissue oxygenation, and that restoration of SNO-Hb levels would improve transfusion efficacy. Notably in mice, administration of banked RBCs decreased skeletal muscle pO2, but infusion of renitrosylated cells maintained tissue oxygenation. In rats, hemorrhage-induced reductions in muscle pO2 were corrected by SNO-Hb-repleted RBCs, but not by control, stored RBCs. In anemic awake sheep, stored renitrosylated, but not control RBCs, produced sustained improvements in O2 delivery; in anesthetized sheep, decrements in hemodynamic status, renal blood flow, and kidney function incurred following transfusion of banked blood were also prevented by renitrosylation. Collectively, our findings lend support to the idea that transfusions may be causally linked to ischemic events and suggest a simple approach to prevention (i.e., SNO-Hb repletion). If these data are replicated in clinical trials, renitrosylation therapy could have significant therapeutic impact on the care of millions of patients.

Interrater reliability of the bedside shivering assessment scale.

BACKGROUND: Since its early development, the Bedside Shivering Assessment Scale (BSAS) has had only initial psychometric testing. Before this instrument is incorporated into routine practice, its interrater reliability should be explored in a diverse group of practitioners. METHODS: This prospective nonrandomized study used a panel of 5 observers who completed 100 paired assessments. Observers independently scored patients for shivering by using the BSAS. Kappa statistics were determined by using SAS version 9.4 with BSAS scores treated as ordinal data. RESULTS: A weighted kappa value of 0.48 from 100 paired observations of 22 patients indicates moderate agreement of the BSAS scores. Most of the BSAS scores were 0 or 1; dichotomizing shivering as little or no shivering versus significant shivering resulted in a kappa of 0.66 (substantial agreement). No relationship was found between timing of assessment or the role of the practitioner and the likelihood of both observers assigning the same BSAS score. CONCLUSION: The BSAS has adequate interrater reliability to be considered for use among a diverse group of practitioners.