Due to unplanned maintenance of the back-end systems supporting article purchase on Cambridge Core, we have taken the decision to temporarily suspend article purchase for the foreseeable future. We apologise for any inconvenience caused whilst we work with the relevant teams to restore this service.
To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Cadaveric and older radiographic studies suggest that concurrent cervical spine fractures are rare in gunshot wounds (GSWs) to the head. Despite this knowledge, patients with craniofacial GSWs often arrive with spinal motion restriction (SMR) in place. This study quantifies the incidence of cervical spine injuries in GSWs to the head, identified using computerized tomography (CT). Fracture frequency is hypothesized to be lower in self-inflicted (SI) injuries.
Isolated craniofacial GSWs were queried from this Level I trauma center registry from 2013-2017 and the US National Trauma Data Bank (NTDB) from 2012–2016 (head or face abbreviated injury scale [AIS] >2). Datasets included age, gender, SI versus not, cervical spine injury, spinal surgery, and mortality. For this hospital’s data, prehospital factors, SMR, and CTs performed were assessed. Statistical evaluation was done with Stata software, with P <.05 significant.
Two-hundred forty-one patients from this hospital (mean age 39; 85% male; 66% SI) and 5,849 from the NTDB (mean age 38; 84% male; 53% SI) were included. For both cohorts, SI patients were older (P < .01) and had increased mortality (P < .01). Overall, cervical spine fractures occurred in 3.7%, with 5.4% requiring spinal surgery (0.2% of all patients). The frequency of fracture was five-fold greater in non-SI (P < .05). Locally, SMR was present in 121 (50.2%) prior to arrival with six collars (2.5%) placed in the trauma bay. Frequency of SMR was similar regardless of SI status (49.0% versus 51.0%; P = not significant) but less frequent in hypotensive patients and those receiving cardiopulmonary resuscitation (CPR). The presence of SMR was associated with an increased use of CT of the cervical spine (80.0% versus 33.0%; P < .01).
Cervical spine fractures were identified in less than four percent of isolated GSWs to the head and face, more frequently in non-SI cases. Prehospital SMR should be avoided in cases consistent with SI injury, and for all others, SMR should be discontinued once CT imaging is completed with negative results.
After five positive randomized controlled trials showed benefit of mechanical thrombectomy in the management of acute ischemic stroke with emergent large-vessel occlusion, a multi-society meeting was organized during the 17th Congress of the World Federation of Interventional and Therapeutic Neuroradiology in October 2017 in Budapest, Hungary. This multi-society meeting was dedicated to establish standards of practice in acute ischemic stroke intervention aiming for a consensus on the minimum requirements for centers providing such treatment. In an ideal situation, all patients would be treated at a center offering a full spectrum of neuroendovascular care (a level 1 center). However, for geographical reasons, some patients are unable to reach such a center in a reasonable period of time. With this in mind, the group paid special attention to define recommendations on the prerequisites of organizing stroke centers providing medical thrombectomy for acute ischemic stroke, but not for other neurovascular diseases (level 2 centers). Finally, some centers will have a stroke unit and offer intravenous thrombolysis, but not any endovascular stroke therapy (level 3 centers). Together, these level 1, 2, and 3 centers form a complete stroke system of care. The multi-society group provides recommendations and a framework for the development of medical thrombectomy services worldwide.
Multiple studies have demonstrated that daily chlorhexidine gluconate (CHG) bathing is associated with a significant reduction in infections caused by gram-positive pathogens. However, there are limited data on the effectiveness of daily CHG bathing on gram-negative infections. The aim of this study was to determine whether daily CHG bathing is effective in reducing the rate of gram-negative infections in adult intensive care unit (ICU) patients.
We searched MEDLINE and 3 other databases for original studies comparing daily bathing with and without CHG. Two investigators extracted data independently on baseline characteristics, study design, form and concentration of CHG, incidence, and outcomes related to gram-negative infections. Data were combined using a random-effects model and pooled relative risk ratios (RRs), and 95% confidence intervals (CIs) were derived.
In total, 15 studies (n = 34,895 patients) met inclusion criteria. Daily CHG bathing was not significantly associated with a lower risk of gram-negative infections compared with controls (RR, 0.89; 95% CI, 0.73–1.08; P = .24). Subgroup analysis demonstrated that daily CHG bathing was not effective for reducing the risk of gram-negative infections caused by Acinetobacter, Escherichia coli, Klebsiella, Enterobacter, or Pseudomonas spp.
The use of daily CHG bathing was not associated with a lower risk of gram-negative infections. Further, better designed trials with adequate power and with gram-negative infections as the primary end point are needed.
Introduction: Emergency Department (ED) staff burnout correlates with psychological coping strategies used by Emergency department health professionals (EDHPs). Staff at two urban referral EDs in New Brunswick took part in a survey of burnout and coping strategies after one ED experienced an influx of new physicians and a newly renovated ED in 2011. Six years later, ED crowding and EDHP staffing problems became prevalent at both EDs. We compared levels of burnout at two urban referral EDs to determine if burnout and coping worsened over time. Methods: An anonymous survey of all EDHPs at 2 urban referral EDs was performed in 2011 and in 2017. A demographics questionnaire, the Maslach Burnout Inventory (MBI, measuring emotional exhaustion, depersonalization and personal accomplishment), and the Coping Inventory for Stressful Situations (CISS, measuring task-oriented, emotion-oriented, and avoidance-oriented coping styles) were collected. Descriptive statistics and linear regression models examined relationships over time and between the two hospitals. Results: Burnout scores were similar both at the two facilities and in 2011 (n=153) and 2017 (n=127). There were no differences between samples or EDs for important factors. Emotion-oriented coping was associated with higher levels of burnout, while task-oriented coping was inversely correlated with burnout. Experiencing professional stress was a significant predictor of emotional exhaustion, while those working longer years in their current department had higher emotional exhaustion and depersonalization. By 2017, both EDs had experienced significant nursing staff turnover (50%) compared to 2011. Conclusion: Burnout scores remained consistent after 6 years at these two urban referral EDs. Given the evidence that increased years of service is associated with increased burnout, high staff turnover rate at both EDs could explain how scores remained constant. Staff turnover may represent a way these ED systems cope in a challenging environment. In 2017, task-oriented copers continued to score lower while emotionally-oriented copers showed higher burnout risk, and experiencing professional stress remains a strong predictor of burnout.
Contaminated hands of healthcare workers (HCWs) are an important source of transmission of healthcare-associated infections. Alcohol-based hand sanitizers, while effective, do not provide sustained antimicrobial activity. The objective of this study was to compare the immediate and persistent activity of 2 hand hygiene products (ethanol [61% w/v] plus chlorhexidine gluconate [CHG; 1.0% solution] and ethanol only [70% v/v]) when used in an intensive care unit (ICU).
Prospective, randomized, double-blinded, crossover study
Three ICUs at a large teaching hospital
In total, 51 HCWs involved in direct patient care were enrolled in and completed the study.
All HCWs were randomized 1:1 to either product. Hand prints were obtained immediately after the product was applied and again after spending 4–7 minutes in the ICU common areas prior to entering a patient room or leaving the area. The numbers of aerobic colony-forming units (CFU) were compared for the 2 groups after log transformation. Each participant tested the alternative product after a 3-day washout period.
On bare hands, use of ethanol plus CHG was associated with significantly lower recovery of aerobic CFU, both immediately after use (0.27 ± 0.05 and 0.88 ± 0.08 log10 CFU; P = .035) and after spending time in ICU common areas (1.81 ± 0.07 and 2.17 ± 0.05 log10 CFU; P<.0001). Both the antiseptics were well tolerated by HCWs.
In comparison to the ethanol-only product, the ethanol plus CHG sanitizer was associated with significantly lower aerobic bacterial counts on hands of HCWs, both immediately after use and after spending time in ICU common areas.
Introduction: Almost every domain of quality is reduced in crowded emergency departments (ED), with significant challenges around the definition, measurement and interventions for ED crowding. We wished to determine if a combination of 3 easily measurable variables could perform as well as standard tools (NEDOCS score and a NEDOCS-derived LOCAL tool) in predicting ED crowding at a tertiary hospital with 57,000 visits per year. Methods: Over a 2-week period, we recorded ED crowding predictor variables and calculated NEDOCS and LOCAL scores. These were compared every 2 hours to a reference standard Physician Visual Analog Scale (range 0 to 10) impression of crowding to determine if any combination of variables outperformed NEDOCS and LOCAL (crowded=5 or greater). Five numeric variables performed well under univariate analysis: i) Total ED Patients; ii) Patients in ED beds + Waiting Room; iii) Boarded Patients; iv) Waiting Room Patients; v) Patients in beds To Be Seen. These underwent multivariate, log regression with stratification and bootstrapping to account for incomplete data and seasonal and daily effect. Results: 143 out of a possible 168 observations were completed. Two different combinations of 3 variables outperformed NEDOCS and LOCAL. The most powerful combination was: Boarded Patients; plus Waiting Room Patients; plus Patients in beds To Be Seen, with Sensitivity 81% and Specificity 76% (r=0.844, β=0.712, p<0.0001, strong positive correlation). This compared favourably with NEDOCS and LOCAL, each with Sensitivity 71% and Specificity 64%[PA1] (r=0.545 and r=0.640 respectively). We will also present a sensitivity and specificity analysis of all combinations of predictor variables, using various reference standard cut-offs for crowding. Conclusion: A combination of 3 easily measurable ED variables (Boarded Patients; plus Waiting Room Patients; plus Patients in beds To Be Seen) performed better than the validated NEDOCS tool and a NEDOCS-derived LOCAL score at predicting ED crowding. Work is on going to design a simple tool that can predict crowding in real time and facilitate early interventions. Correlation with ED system and clinical outcomes should be studied in different ED environments.
Introduction: Point of care ultrasound (US) is a key adjunct in the management of trauma patients, in the form of the extended focused assessment with sonography in trauma (E-FAST) scan. This study assessed the impact of adding an edus2 ultrasound simulator on the diagnostic capabilities of resident and attending physicians participating in simulated trauma scenarios. Methods: 12 residents and 20 attending physicians participated in 114 trauma simulations utilizing a Laerdal 3G mannequin. Participants generated a ranked differential diagnosis list after a standard assessment, and again after completing a simulated US scan for each scenario. We compared reports to determine if US improved diagnostic performance over a physical exam alone. Standard statistical tests (χ2 and Student t tests) were performed. The research team was independent of the edus2 designers. Results: Primary diagnosis improved significantly from 53 (46%) to 97 (85%) correct diagnoses with the addition of simulated US (χ2=37.7, 1df; p=<0.0001). Of the 61 scenarios where an incorrect top ranked diagnosis was given, 51 (84%) improved following US. Participants were assigned a score from 1 to 5 based on where the correct diagnosis was ranked, with a 5 indicating a correct primary diagnosis. Median scores significantly increased from 3.8 (IQR 3, 4.9) to 5 (IQR 4.7, 5; W=219, p<0.0001).Participants were significantly more confident in their diagnoses after using the US simulator, as shown by the increase in their mean confidence in the correct diagnosis from 53.1% (SD 22.8) to 83.5% (SD 19.1; t=9.0; p<0.0001)Additionally, participants significantly narrowed their differential diagnosis lists from an initial medium count of 3.5 (IQR 2.9, 4.4) possible diagnoses to 2.4 (IQR 1.9, 3; W=-378, p<0.0001) following US. The performance of residents was compared to that of attending physicians for each of the above analyses. No differences in performance were detected. Conclusion: This study showed that the addition of ultrasound to simulated trauma scenarios improved the diagnostic capabilities of resident and attending physicians. Specifically, participants improved in diagnostic accuracy, diagnostic confidence, and diagnostic precision. Additionally, we have shown that the edus2 simulator can be integrated into high fidelity simulation in a way that improves diagnostic performance.
Introduction: Point of care ultrasound (PoCUS) is an established tool in the initial management of patients with undifferentiated hypotension in the emergency department (ED). While PoCUS protocols have been shown to improve early diagnostic accuracy, there is little published evidence for any mortality benefit. We report the findings from our international multicenter randomized controlled trial, assessing the impact of a PoCUS protocol on survival and key clinical outcomes. Methods: Recruitment occurred at 7 centres in North America (4) and South Africa (3). Scans were performed by PoCUS-trained physicians. Screening at triage identified patients (SBP<100 or shock index>1), randomized to PoCUS or control (standard care and no PoCUS) groups. Demographics, clinical details and study findings were collected prospectively. Initial and secondary diagnoses were recorded at 0 and 60 minutes, with ultrasound performed in the PoCUS group prior to secondary assessment. The primary outcome measure was 30-day/discharge mortality. Secondary outcome measures included diagnostic accuracy, changes in vital signs, acid-base status, and length of stay. Categorical data was analyzed using Fishers test, and continuous data by Student T test and multi-level log-regression testing. (GraphPad/SPSS) Final chart review was blinded to initial impressions and PoCUS findings. Results: 258 patients were enrolled with follow-up fully completed. Baseline comparisons confirmed effective randomization. There was no difference between groups for the primary outcome of mortality; PoCUS 32/129 (24.8%; 95% CI 14.3-35.3%) vs. Control 32/129 (24.8%; 95% CI 14.3-35.3%); RR 1.00 (95% CI 0.869 to 1.15; p=1.00). There were no differences in the secondary outcomes; ICU and total length of stay. Our sample size has a power of 0.80 (α:0.05) for a moderate effect size. Other secondary outcomes are reported separately. Conclusion: This is the first RCT to compare PoCUS to standard care for undifferentiated hypotensive ED patients. We did not find any mortality or length of stay benefits with the use of a PoCUS protocol, though a larger study is required to confirm these findings. While PoCUS may have diagnostic benefits, these may not translate into a survival benefit effect.
Introduction: Point of Care Ultrasound (PoCUS) protocols are commonly used to guide resuscitation for emergency department (ED) patients with undifferentiated non-traumatic hypotension. While PoCUS has been shown to improve early diagnosis, there is a minimal evidence for any outcome benefit. We completed an international multicenter randomized controlled trial (RCT) to assess the impact of a PoCUS protocol on key resuscitation markers in this group. We report diagnostic impact and mortality elsewhere. Methods: The SHoC-ED1 study compared the addition of PoCUS to standard care within the first hour in the treatment of adult patients presenting with undifferentiated hypotension (SBP<100 mmHg or a Shock Index >1.0) with a control group that did not receive PoCUS. Scans were performed by PoCUS-trained physicians. 4 North American, and 3 South African sites participated in the study. Resuscitation outcomes analyzed included volume of fluid administered in the ED, changes in shock index (SI), modified early warning score (MEWS), venous acid-base balance, and lactate, at one and four hours. Comparisons utilized a T-test as well as stratified binomial log-regression to assess for any significant improvement in resuscitation amount the outcomes. Our sample size was powered at 0.80 (α:0.05) for a moderate effect size. Results: 258 patients were enrolled with follow-up fully completed. Baseline comparisons confirmed effective randomization. There was no significant difference in mean total volume of fluid received between the control (1658 ml; 95%CI 1365-1950) and PoCUS groups (1609 ml; 1385-1832; p=0.79). Significant improvements were seen in SI, MEWS, lactate and bicarbonate with resuscitation in both the PoCUS and control groups, however there was no difference between groups. Conclusion: SHOC-ED1 is the first RCT to compare PoCUS to standard of care in hypotensive ED patients. No significant difference in fluid used, or markers of resuscitation was found when comparing the use of a PoCUS protocol to that of standard of care in the resuscitation of patients with undifferentiated hypotension.
Introduction: Point of care ultrasonography (PoCUS) is an established tool in the initial management of hypotensive patients in the emergency department (ED). It has been shown rule out certain shock etiologies, and improve diagnostic certainty, however evidence on benefit in the management of hypotensive patients is limited. We report the findings from our international multicenter RCT assessing the impact of a PoCUS protocol on diagnostic accuracy, as well as other key outcomes including mortality, which are reported elsewhere. Methods: Recruitment occurred at 4 North American and 3 Southern African sites. Screening at triage identified patients (SBP<100 mmHg or shock index >1) who were randomized to either PoCUS or control groups. Scans were performed by PoCUS-trained physicians. Demographics, clinical details and findings were collected prospectively. Initial and secondary diagnoses were recorded at 0 and 60 minutes, with ultrasound performed in the PoCUS group prior to secondary assessment. Final chart review was blinded to initial impressions and PoCUS findings. Categorical data was analyzed using Fishers two-tailed test. Our sample size was powered at 0.80 (α:0.05) for a moderate effect size. Results: 258 patients were enrolled with follow-up fully completed. Baseline comparisons confirmed effective randomization. The perceived shock category changed more frequently in the PoCUS group 20/127 (15.7%) vs. control 7/125 (5.6%); RR 2.81 (95% CI 1.23 to 6.42; p=0.0134). There was no significant difference in change of diagnostic impression between groups PoCUS 39/123 (31.7%) vs control 34/124 (27.4%); RR 1.16 (95% CI 0.786 to 1.70; p=0.4879). There was no significant difference in the rate of correct category of shock between PoCUS (118/127; 93%) and control (113/122; 93%); RR 1.00 (95% CI 0.936 to 1.08; p=1.00), or for correct diagnosis; PoCUS 90/127 (70%) vs control 86/122 (70%); RR 0.987 (95% CI 0.671 to 1.45; p=1.00). Conclusion: This is the first RCT to compare PoCUS to standard care for undifferentiated hypotensive ED patients. We found that the use of PoCUS did change physicians’ perceived shock category. PoCUS did not improve diagnostic accuracy for category of shock or diagnosis.
Catheter-associated urinary tract infections (CAUTIs) are among the most common hospital-acquired infections (HAIs). Reducing CAUTI rates has become a major focus of attention due to increasing public health concerns and reimbursement implications.
To implement and describe a multifaceted intervention to decrease CAUTIs in our ICUs with an emphasis on indications for obtaining a urine culture.
A project team composed of all critical care disciplines was assembled to address an institutional goal of decreasing CAUTIs. Interventions implemented between year 1 and year 2 included protocols recommended by the Centers for Disease Control and Prevention for placement, maintenance, and removal of catheters. Leaders from all critical care disciplines agreed to align routine culturing practice with American College of Critical Care Medicine (ACCCM) and Infectious Disease Society of America (IDSA) guidelines for evaluating a fever in a critically ill patient. Surveillance data for CAUTI and hospital-acquired bloodstream infection (HABSI) were recorded prospectively according to National Healthcare Safety Network (NHSN) protocols. Device utilization ratios (DURs), rates of CAUTI, HABSI, and urine cultures were calculated and compared.
The CAUTI rate decreased from 3.0 per 1,000 catheter days in 2013 to 1.9 in 2014. The DUR was 0.7 in 2013 and 0.68 in 2014. The HABSI rates per 1,000 patient days decreased from 2.8 in 2013 to 2.4 in 2014.
Effectively reducing ICU CAUTI rates requires a multifaceted and collaborative approach; stewardship of culturing was a key and safe component of our successful reduction efforts.
Amorphous solid water (ASW) is of great importance in astrochemistry as it has been detected in star forming regions, comets, and cold solar-system objects. A key property of ASW is its porous nature (with the extent of porosity reflecting the formation and growth conditions) and the subsequent pore collapse when the ice is heated. If interstellar ices are porous there are huge implications to both the process of planet formation and the budgets of molecular gas in the solid and gas phases. It is therefore vital to understand ASW porosity over astronomically relevant conditions in order to effectively model its potential effects on these processes.
An estimated 20–30% of patients with primary Clostridium difficile infection (CDI) develop recurrent CDI (rCDI) within 2 weeks of completion of therapy. While the actual mechanism of recurrence remains unknown, a variety of risk factors have been suggested and studied. The aim of this systematic review and meta-analysis was to evaluate current evidence on the risk factors for rCDI.
We searched MEDLINE and 5 other databases for subject headings and text related to rCDI. All studies investigating risk factors of rCDI in a multivariate model were eligible. Information on study design, patient population, and assessed risk factors were collected. Data were combined using a random-effects model and pooled relative risk ratios (RRs) were calculated.
A total of 33 studies (n=18,530) met the inclusion criteria. The most frequent independent risk factors associated with rCDI were age≥65 years (risk ratio [RR], 1.63; 95% confidence interval [CI], 1.24–2.14; P=.0005), additional antibiotics during follow-up (RR, 1.76; 95% CI, 1.52–2.05; P<.00001), use of proton-pump inhibitors (PPIs) (RR, 1.58; 95% CI, 1.13–2.21; P=.008), and renal insufficiency (RR, 1.59; 95% CI, 1.14–2.23; P=.007). The risk was also greater in patients previously on fluoroquinolones (RR, 1.42; 95% CI, 1.28–1.57; P<.00001).
Multiple risk factors are associated with the development of rCDI. Identification of modifiable risk factors and judicious use of antibiotics and PPI can play an important role in the prevention of rCDI.
Our aim was to describe the epidemiology and incidence of community-onset invasive S. aureus disease in children presenting to our hospital, and to compare the clonal complexes and virulence genes of S. aureus strains causing invasive and non-invasive disease. The virulence gene repertoire of invasive disease isolates was characterized using DNA microarray and compared with the virulence gene repertoire of non-invasive S. aureus isolates. Over the study period, 163 children had an invasive S. aureus infection. There was no difference in the distribution of clonal complexes or in the prevalence of genes encoding virulence factors between invasive and non-invasive isolates. Future research should include a strong focus on identifying the host and environmental factors that, along with organism virulence factors, are contributing to the patterns of invasive S. aureus disease observed in New Zealand.
In light of the low success rate of target-based genomics and HTS (High Throughput Screening) approaches in anti-infective drug discovery, in silico structure-based drug design (SBDD) is becoming increasingly prominent at the forefront of drug discovery. In silico SBDD can be used to identify novel enzyme inhibitors rapidly, where the strength of this approach lies with its ability to model and predict the outcome of protein-ligand binding. Over the past 10 years, our group have applied this approach to a diverse number of anti-infective drug targets ranging from bacterial D-ala-D-ala ligase to Plasmodium falciparum DHODH. Our search for new inhibitors has produced lead compounds with both enzyme and whole-cell activity with established on-target mode of action. This has been achieved with greater speed and efficiency compared with the more traditional HTS initiatives and at significantly reduced cost and manpower.
The Post Quarry, within the lower part of the type section of the Upper Triassic Cooper Canyon Formation in southern Garza County, western Texas, contains a remarkably diverse vertebrate assemblage. The Post Quarry has produced: the small temnospondyl Rileymillerus cosgriffi; the metoposaurid Apachesaurus gregorii; possible dicynodonts and eucynodonts; a clevosaurid sphenodontian; non-archosauriform archosauromorphs (Trilophosaurus dornorum, simiosaurians, and possibly Malerisaurus); the phytosaur Leptosuchus; several aetosaurs (Calyptosuchus wellesi, Typothorax coccinarum, Paratypothorax, and Desmatosuchus smalli); the poposauroid Shuvosaurus inexpectatus (“Chatterjeea elegans”); the rauisuchid Postosuchus kirkpatricki; an early crocodylomorph; several dinosauromorphs (the lagerpetid Dromomeron gregorii, the silesaurid Technosaurus smalli, a herrerasaurid, and an early neotheropod); and several enigmatic small diapsids. Revised lithostratigraphic correlations of the lower Cooper Canyon Formation with the Tecovas Formation, the occurrence of Leptosuchus, and the overall composition of the assemblage indicate that the Post Quarry falls within the Adamanian biozone, and not the Revueltian biozone. Stratigraphic subdivision of the Adamanian biozone may be possible, and the Post Quarry may be correlative with the upper part of the Adamanian biozone in Arizona. The age of the Post Quarry assemblage is possibly late Lacian or earliest Alaunian (late early Norian or earliest middle Norian), between 220 and 215 Ma.
To develop a modified surveillance definition of central line-associated bloodstream infection (mCLABSI) specific for our population of patients with hematologic malignancies to better support ongoing improvement efforts at our hospital.
Retrospective cohort study.
Hematologic malignancies population in a 1,200-bed tertiary care hospital on a 22-bed bone marrow transplant (BMT) unit and a 22-bed leukemia unit.
An mCLABSI definition was developed, and pathogens and rates were compared against those determined using the National Healthcare Safety Network (NHSN) definition.
By the NHSN definition the CLABSI rate on the BMT unit was 6.0 per 1,000 central line-days, and by the mCLABSI definition the rate was 2.0 per 1,000 line-days (P < .001). On the leukemia unit, the NHSN CLABSI rate was 14.4 per 1,000 line-days, and the mCLABSI rate was 8.2 per 1,000 line-days (P = .009). The top 3 CLABSI pathogens by the NHSN definition were Enterococcus species, Klebsiella species, and Escherichia coli. The top 3 CLABSI pathogens by the mCLABSI definition were coagulase-negative Staphylococcus (CONS), Pseudomonas aeruginosa, and Staphylococcus aureus. The difference in the incidence of CONS as a cause of CLABSI under the 2 definitions was statistically significant (P < .001).
A modified surveillance definition of CLABSI was associated with an increase in the identification of staphylococci as the cause of CLABSIs, as opposed to enteric pathogens, and a decrease in CLABSI rates.
The success of central line-associated bloodstream infection (CLABSI) prevention programs in intensive care units (ICUs) has led to the expansion of surveillance at many hospitals. We sought to compare non-ICU CLABSI (nCLABSI) rates with national reports and describe methods of surveillance at several participating US institutions.
Design and Setting.
An electronic survey of several medical centers about infection surveillance practices and rate data for non-ICU Patients.
Ten tertiary care hospitals.
In March 2011, a survey was sent to 10 medical centers. The survey consisted of 12 questions regarding demographics and CLABSI surveillance methodology for non-ICU patients at each center. Participants were also asked to provide available rate and device utilization data.
Hospitals ranged in size from 238 to 1,400 total beds (median, 815). All hospitals reported using Centers for Disease Control and Prevention (CDC) definitions. Denominators were collected by different means: counting patients with central lines every day (5 hospitals), indirectly estimating on the basis of electronic orders (n = 4), or another automated method (n = 1). Rates of nCLABSI ranged from 0.2 to 4.2 infections per 1,000 catheter-days (median, 2.5). The national rate reported by the CDC using 2009 data from the National Healthcare Surveillance Network was 1.14 infections per 1,000 catheter-days.
Only 2 hospitals were below the pooled CLABSI rate for inpatient wards; all others exceeded this rate. Possible explanations include differences in average central line utilization or hospital size in the impact of certain clinical risk factors notably absent from the definition and in interpretation and reporting practices. Further investigation is necessary to determine whether the national benchmarks are low or whether the hospitals surveyed here represent a selection of outliers.
In this chapter, we explore the challenges that Earth system researchers face in addressing human-induced global environmental changes and the societal consequences of global change within their research toolkit. We focus on areas of research that have particular resonance with today’s social and political demands.
The Earth system and the ‘problematic human’
The state of play and our position
The great scientific challenge faced by today’s global change scientists is to understand the Earth system. Part of this is knowing that we ourselves, as human beings, are an influential component of that system and that the understanding we develop shapes our responses to the environmental changes we see around us. In scientific terms, most of the fundamental workings of our planet, including the processes that change climate and landscapes on short and long timescales, were already well understood by the end of the twentieth century. Earth system science is the field of study that has brought these areas of knowledge together. It has not just provided insight into the phenomena of global environmental change, but also explained the ‘hows’ and ‘whys’ behind them, bringing insights into the future prospects for our planet. The enormity of the challenge lies in the realization that we are seeking to understand and predict the properties of a complex adaptive system of which we are a part, recognizing that our choices and our agency as human beings are important controls on its workings. More than that, our ability to deploy our knowledge and make choices about our actions is an important facet, perhaps even a characterizing trait, of our existence.
Under lowland conditions there is evidence to indicate that animals consuming ryegrasses bred for elevated water-soluble carbohydrate (WSC) concentrations are able to utilize the protein in their diet more efficiently, resulting in increased live-weight gain, milk production and lower loss of N. The current study evaluated the effects on upland sheep production of grazing two cultivars of perennial ryegrass nominally differing in WSC content. Replicate plots (n=4) of a cultivar bred for elevated levels of WSC (AberDart) and a control cultivar (Fennema) were grazed by ewes and lambs (pre-weaning) and by lambs only (post-weaning). Target surface sward heights of 40 and 60–70 mm were maintained during the pre-weaning and post-weaning periods, respectively. No differences were found in the WSC concentration of the two swards during either the pre-weaning or post-weaning periods. However, cultivar AberDart had a significantly lower fibre concentration during both periods (P<0·05), and a higher digestibility of organic matter in dry matter (DOMD) value during the post-weaning period (P<0·05). There was no cultivar effect of treatment on lamb growth during the pre-weaning period, but lamb live-weight gain was significantly higher for those grazing AberDart than Fennema during the post-weaning period (200 g/d v. 125 g/d; s.e.d.=26·5 g/d; P<0·01), leading to a greater proportion of lambs selected for slaughter by the end of September (0·99 v. 0·70 respectively; s.e.d.=0·062; P<0·05). The improved performance for lambs grazing AberDart relative to those grazing Fennema indicates that advances in plant breeding have the potential to improve the efficiency and profitability of lamb production in the uplands. However, additional research is required to explore the extent to which growing conditions in marginal environments influence the expression of traits.