Method development for rapid quantification of Rn-222 in surface water and groundwater.

Understanding the risks of a developing unconventional hydrocarbons industry, including shale gas, to the chemical quality of surface water and groundwater involves firstly establishing baseline compositions against which any future changes can be assessed. Contaminants of geogenic origin are of particular interest and radon has been identified as one potential contaminant from shale sources. Robust measurement and monitoring of radon in water at environmental concentrations is essential for ensuring protection of water sources and maintaining public confidence. Traditional techniques for Rn-222 determination in water, such as inference by gamma spectrometry and direct alpha counting, are impractical for direct field measurement, and the relatively short half-life of Rn-222 (~ 3.82 days) means that longer analytical protocols from field to the laboratory may result in greater uncertainty for Rn-222 activity. Therefore, a rapid and low-cost method would be beneficial. We have developed and refined a laboratory procedure for Rn-222 monitoring using liquid scintillation counting (LSC). The accuracy of Rn-222 activities obtained via this procedure was evaluated by the analysis of almost 200 water samples collected from streams and boreholes as part of a detailed baseline investigation in the Vale of Pickering, Yorkshire, one potential location for future shale gas exploration. LSC was preferred for measurement of Rn-222 and had comparable accuracy to gamma spectrometry and direct alpha counting. The methodology provided a rapid, portable and low-maintenance option relative to the two established techniques and is shown to be a favourable choice for the measurement of radon in surface water and groundwater at environmental concentrations.

When in Doubt, Pull the Catheter Out: Implementation of an Evidence-Based Protocol in the Prevention and Management of Peripheral Intravenous Infiltration/Extravasation in Neonates.

The vast majority of infants in the NICU receive peripheral intravenous (PIV) therapy for administration of fluids, nutrition, medications, and blood products. The potential complications of infiltration and extravasation are common in this population. Consequences of inf.ltration and extravasation may be prevented or mitigated by early detection and prompt treatment. In addition, innovative therapies for wound care are constantly evolving. In order to improve outcomes, a practice guideline for intravenous (IV) infiltration prevention, management, and treatment is presented based on literature review and consultation with wound care experts. The guideline includes preventive measures, standardized IV assessment, staging, an algorithm outlining injury, and wound care recommendations.

Favorable Outcomes of Preterm Infants With Parenteral Nutrition-associated Liver Disease Treated With Intravenous Fish Oil-based Lipid Emulsion.

OBJECTIVES: The aim of the study was to determine the acute and long-term outcomes of preterm infants treated with an intravenous fish oil-based lipid emulsion (FishLE) for parenteral nutrition-associated liver disease (PNALD). METHODS: Preterm infants 14 days to 24 months of age with anatomic short gut or severe intestinal dysmotility, serum direct bilirubin ≥4 mg/dL, and requiring >60% calories from parenteral nutrition were eligible. Enrolled infants received 1 g ·â€Škg ·â€Šday of FishLE until resolution of direct hyperbilirubinemia or return of enteral nutrition. Acute clinical effects and biochemical markers of liver function were monitored. Growth and developmental scores at 6 and 12 months postmenstrual age (PMA) were assessed and compared with controls matched by gestational age (GA). RESULTS: Thirteen patients with mean GA of 28 ±â€Š4 weeks were treated and compared with 119 GA-matched controls. Their mean direct bilirubin was 9.8 ±â€Š6.4 mg/dL at enrollment. All infants had resolution of cholestasis after study completion. There were no acute adverse events, deaths, or liver/intestinal transplants. Weight and head circumference were similar between FishLE-treated patients and controls at 6- and 12-month PMA. Cognitive and motor scores were decreased at 6 and 12 months PMA in FishLE-treated infants. Logistic regression analysis showed that prolonged hospitalization was detrimental to cognitive and motor development, whereas treatment was not. CONCLUSIONS: The use of intravenous FishLEs in premature infants appears to be safe and reverses PNALD despite significant liver disease and intestinal failure. This therapy should be used in preterm infants with PNALD and followed long term to evaluate development.

Long-term CO2 injection and its impact on near-surface soil microbiology.

Impacts of long-term CO2 exposure on environmental processes and microbial populations of near-surface soils are poorly understood. This near-surface long-term CO2 injection study demonstrated that soil microbiology and geochemistry is influenced more by seasonal parameters than elevated CO2 Soil samples were taken during a 3-year field experiment including sampling campaigns before, during and after 24 months of continuous CO2 injection. CO2 concentrations within CO2-injected plots increased up to 23% during the injection period. No CO2 impacts on geochemistry were detected over time. In addition, CO2-exposed samples did not show significant changes in microbial CO2 and CH4 turnover rates compared to reference samples. Likewise, no significant CO2-induced variations were detected for the abundance of Bacteria, Archaea (16S rDNA) and gene copy numbers of the mcrA gene, Crenarchaeota and amoA gene. The majority (75%-95%) of the bacterial sequences were assigned to five phyla: Firmicutes, Proteobacteria, Actinobacteria, Acidobacteria and Bacteroidetes The majority of the archaeal sequences (85%-100%) were assigned to the thaumarchaeotal cluster I.1b (soil group). Univariate and multivariate statistical as well as principal component analyses showed no significant CO2-induced variation. Instead, seasonal impacts especially temperature and precipitation were detected.

Retrospective analysis of levetiracetam compared to phenytoin for seizure prophylaxis in adults with traumatic brain injury.

BACKGROUND: Phenytoin is standard of care for seizure prophylaxis following traumatic brain injury (TBI). Levetiracetam, an alternative antiepileptic drug, is utilized for seizure prophylaxis despite limited data supporting its use. OBJECTIVE: Our primary outcome was post-TBI seizure activity measured by electroencephalogram (EEG) for levetiracetam versus phenytoin. Secondary outcomes were length of intensive care unit (ICU) stay, requirement for additional antiepileptic drugs (AED), and drug and monitoring costs. METHODS: A retrospective review was performed of patients admitted to neurosurgical or surgical trauma ICU. Adult patients with at least 1 day of EEG monitoring were included. Patients were excluded if they had history of epilepsy, prior TBI, less than 48 hours of AED therapy, or additional AED prior to EEG monitoring. RESULTS: A total 90 patients met inclusion criteria, with 18 receiving levetiracetam and 72 receiving phenytoin. Prevalence of EEG-confirmed seizure activity was similar between the levetiracetam and phenytoin groups (28% vs 29%; P = .99). ICU length of stay (13 vs 18 days; P = .28), time to EEG-confirmed seizure activity (4 vs 6 days; P = .24), and duration of seizure prophylaxis (9 vs 14 days; P = .18) were also similar. The median daily cost of levetiracetam therapy was $43 compared to $55 for phenytoin therapy and monitoring (P = .08). When all anticonvulsant therapy and monitoring were included, costs were lower for the levetiracetam group ($45 vs $83; P = .02). CONCLUSION: Levetiracetam may provide an alternative treatment option for seizure prevention in TBI patients in the ICU. Total antiepileptic drug and monitoring costs were lower for levetiracetam patients.

Monotherapy or combination therapy? The Pseudomonas aeruginosa conundrum.

Abstract The use of combination antibiotic therapy for severe pseudomonal infections is a standard practice in many hospitals; however, the data supporting its use are somewhat unclear. Possible benefits of combination therapy for Pseudomonas aeruginosa infections include in vitro antibiotic synergy, prevention of the emergence of bacterial resistance while receiving therapy, and improved adequacy of empiric therapy. Unfortunately, the potential disadvantages are also considerable, the most worrisome of which are drug toxicity and creation of multidrug-resistant organisms in the environment. Many in vitro and animal studies have attempted to shed light on this clinically challenging issue; however, these studies have often yielded conflicting results and used different study methods, which limits the clinical utility of the results. Clinical studies have also attempted to clarify this issue, particularly in patients with serious pseudomonal infections such as bacteremia and ventilator-associated pneumonia, but again, often resulted in conflicting conclusions. Thus, we performed a MEDLINE search (1950-May 2010) of clinical and in vitro studies evaluating the use of antibiotic combination therapy and monotherapy for bacteremia and pneumonia due to P. aeruginosa. Although a clear answer still eludes this controversy, combination therapy for seriously ill patients suspected of having pseudomonal infection has been shown, with considerable evidence, to improve the likelihood of an active agent being included in the initial antibiotic regimen of these patients. The clinical status of the patient and true likelihood of encountering a multidrug-resistant organism should be evaluated before deciding on empiric combination therapy. Future research may be able to better identify which patient populations might receive the most benefit from combination therapy rather than using combination therapy for everyone at risk for these infections.

Pravastatin versus simvastatin for prevention of contrast-induced nephropathy.

Contrast-induced nephropathy (CIN) is associated with long-term morbidity, mortality, and increased health care costs. It has been suggested that statins have pleiotropic effects countering inflammatory and oxidative stress involved in CIN. Several studies support this theory; however, previously published studies have not evaluated the potential differences between statins in reducing the incidence of CIN. The purpose of this retrospective, single-center trial was to compare the incidence of CIN in patients receiving simvastatin or pravastatin therapy undergoing percutaneous coronary intervention (PCI). A total of 261 patients were included (145 received simvastatin and 116 received pravastatin) with the majority undergoing elective PCI. The population was predominantly male (65%), Hispanic (65%), and diabetic (62%), with a mean age of 59 years and a low-density lipoprotein (LDL) of 85 mg/dL. No significant differences were found between groups for risk factors or prophylactic strategies (eg, hydration). Contrast-induced nephropathy occurred in 26 patients (17.9%) in the simvastatin group versus 10 (8.6%) in the pravastatin group (P < .05). No patients required dialysis as a result of contrast administration. Acute kidney injury (AKI) occurred in 21 patients (14.5%) in the simvastatin group compared to 8 (6.9%) in the pravastatin group (P < .05). In multivariate analysis, the difference between statins remained an independent predictor for the development of CIN. In conclusion, patients on pravastatin had a significantly lower incidence of CIN compared to patients on simvastatin.

Effects of therapeutic drug monitoring criteria in a computerized prescriber-order-entry system on the appropriateness of vancomycin level orders.

PURPOSE: The effects of therapeutic drug monitoring (TDM) criteria in a computerized prescriber-order-entry (CPOE) system on the appropriateness of orders for vancomycin levels were evaluated. METHODS: Vancomycin TDM criteria were developed and implemented in a CPOE system. These criteria were displayed via a pop-up alert message when vancomycin levels were ordered and included directions for appropriate timing and justification for routine monitoring. Data for two groups of adult inpatients who had vancomycin levels ordered before and after criteria implementation were compared. Medical records were retrospectively reviewed for these patients to collect information regarding patient demographics, vancomycin dosage and indication, concurrent antibiotics and nephrotoxic agents during vancomycin therapy, length of stay, duration of vancomycin therapy, and number of vancomycin levels drawn. The primary outcome was the percent change in appropriate vancomycin levels ordered after criteria implementation. RESULTS: A total of 200 patients were analyzed, 100 in each group. The percentage of appropriate orders for vancomycin levels significantly increased after criteria implementation (from 58% to 68%, p = 0.02). The greatest effect on appropriateness occurred with the first level ordered (52% versus 70% in the preimplementation and postimplementation groups, respectively; p = 0.01). The majority of inappropriate levels were due to improper timing of sample collections, accounting for 55% of the inappropriate levels evaluated. CONCLUSION: A significant increase in the number of appropriately ordered and drawn serum vancomycin levels occurred after implementation of TDM criteria in the hospital's CPOE system. The majority of orders that were deemed inappropriate were due to improper timing of laboratory collection.

Continuous versus intermittent infusion of oxacillin for treatment of infective endocarditis caused by methicillin-susceptible Staphylococcus aureus.

Infective endocarditis (IE) is the fourth leading cause of life-threatening infection in the United States and imposes significant morbidity and mortality. The American Heart Association guidelines for the diagnosis and treatment of IE do not address continuous-infusion (CI) oxacillin. This retrospective study compares outcomes between CI oxacillin and intermittent-infusion (II) oxacillin in the treatment of IE caused by methicillin-susceptible Staphylococcus aureus (MSSA). A total of 709 medical records were reviewed for inpatients with definitive IE treated between 1 January 2000 and 31 December 2007. Continuous data were analyzed by Student's t test or the Wilcoxon rank sum test. The chi-square test or Fisher's exact test was used to compare nominal data. A multivariate logistic model was constructed. One hundred seven patients met eligibility criteria for inclusion into the study. Seventy-eight patients received CI oxacillin, whereas 28 received II oxacillin. CI and II groups were similar with respect to 30-day mortality (8% versus 10%, P = 0.7) and length of stay (20 versus 25 days, P = 0.4) but differed in 30-day microbiological cure (94% versus 79%, P = 0.03). Sixty-three patients received synergistic gentamicin, whereas 44 did not. The gentamicin and no-gentamicin groups were similar with respect to 30-day mortality (11% versus 4%, P = 0.2) and 30-day microbiological cure (90% versus 89%, P = 0.8); however, times to defervescence (4 versus 2 days, P = 0.02) were significantly different. CI oxacillin is an effective alternative to II oxacillin for the treatment of IE caused by MSSA and may improve microbiological cure. This convenient and pharmacodynamically optimized dosing regimen for oxacillin deserves consideration for patients with IE caused by MSSA.