Large scale motions of Neptune's bow shock: Evidence for control of the shock position by the rotation phase of Neptune's magnetic field

The Voyager 2 spacecraft observed high levels of Langmuir waves before the inbound crossing of Neptune's bow shock, thereby signifying magnetic connection of the bow shock. The Langmuir waves occurred in multiple bursts throughout two distinct periods separated by an 85 minute absence of wave activity. The times of onsets, peaks, and disappearances of the waves were used together with the magnetic field directions and spacecraft position, to perform a 'remote-sensing' analysis of the shape and location of Neptune's bow shock prior to the inbound bow shock crossing. The bow shock is assumed to have a parabolidal shape with a nose location and flaring parameter determined independently for each wave event. The remote-sensing analysis give a shock position consistent with the time of the inbound shock crossing. The flaring parameter of the shock remains approximately constant throughout each period of wave activity but differs by a factor of 10 between the two periods. The absence of waves between two periods of wave activity coincides with a large rotation of the magnetic field and a large increase in the solar wind ram pressure' both these effects lead to magnetic disconnection of the spacecraft from shock. The planetwards motion of the shock's nose from 38.5 R(sub N) to 34.5 R(sub N) during the second time period occurred while the solar wind ram pressure remained constant to within 15 percent. This second period of planetwards motion of the shock is therefore strong evidence for Neptune's bow shock moving in response to the rotation of Neptune's oblique, tilted magnetic dipole. Normalizing the ram pressure, the remotely-sensed shock moves sunwards during the first wave period and planetwards in the second wave period. The maximum standoff distance occurs while the dipole axis is close to being perpendicular to the Sun-Neptune direction. The remote-sensing analysis provides strong evidence that the location of Neptune's bow shock is controlled by Neptune's rotation phase

The measured effect magnitude of co-morbidities on burn injury mortality

The ability to better prognosticate burn injury outcome is challenging and historically, most center use the Baux or revised Baux score to help prognosticate burn outcome, however, the weighted contribution of comorbidity on burn mortality has traditionally not been accounted for nor adequately studied. We therefore sought to determine the effect of comorbidities, using the Charlson comorbidity index (CCI) on burn mortality

Case Report: A patient with severe peritonitis

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Variations in injury characteristics among paediatric patients following trauma: A retrospective descriptive analysis comparing pre-hospital and in-hospital deaths at Kamuzu Central Hospital, Lilongwe, Malawi

Background: Trauma is a major cause of paediatric mortality in sub-Saharan Africa. In absence of pre-hospital care, the injury mechanism and cause of death is difficult to characterise. Injury characteristics of pre-hospital deaths (PHD) versus in-hospital deaths (IHD) were compared.Methods: Using our trauma surveillance database, a retrospective, descriptive analysis of children (<18 years) presenting to Kamuzu Central Hospital in Lilongwe, Malawi from 2008 to 2013 was performed. Patient and injury characteristics of pre-hospital and in-hospital deaths were compared with univariate and bivariate analysis.Results: Of 30,462 paediatric trauma patients presenting between 2008 and 2013, 170 and 173 were PHD and IHD, respectively. In PHD and IHD patients mean age was 7.3±4.9 v 5.2±4.3 (p<0.001), respectively. IHD patients were more likely transported via ambulance than those PHD, 51.2% v 8.3% (p<0.001). The primary mechanisms of injury for PHD were road traffic injuries (RTI) (45.8%) and drowning (22.0%), with head injury (46.7%) being the predominant cause of death. Burns were the leading mechanism of injury (61.8%) and cause of death (61.9%) in IHD, with a mean total body surface area involvement of 24.7±16.0%.Conclusions: RTI remains Malawi’s major driver of paediatric mortality. A majority of these deaths attributed to head injury occur prior to hospitalisation; therefore the mortality burden is underestimated if accounting for IHD alone. Death in burn patients is likely due to under-resuscitation or sepsis. Improving pre-hospital care and head injury and burn management can improve injury related paediatric mortality

Unsuspected Pulmonary Embolism in Observation Unit Patients

Objective: Many emergency department (ED) patients with cardiopulmonary symptoms such as chest pain or dyspnea are placed in observation units but do not undergo specific diagnostic testing for pulmonary embolism (PE). The role of observation units in the diagnosis of PE has not been studied. We hypothesized that there was a small but significant rate of unsuspected PE in our observation unit population.Methods: We performed a retrospective chart review at an urban academic hospital of all ED patients with an International Classification of Diseases, Ninth Revision diagnosis of PE between January 2005 and July 2006. The number of such patients assigned to observation at any point in their stay was recorded, in addition to events leading to diagnosis and subsequent in-hospital outcomes.Results: Thirteen of the 190 ED patients diagnosed with PE were placed in the observation unit. Six of these either had a known recent diagnosis of PE or had testing for PE initiated prior to placement in the observation unit. Two of the remaining seven patients with undiagnosed PE were placed in observation for undifferentiated chest pain, accounting for 0.09% of the 2190 patients under the chest pain protocol. Twelve of 13 PE patients (92%) were admitted with an average stay of 4.3 days. Of the 13 patients, five were ultimately determined after admission to not have PE, leaving a rate of confirmed PE in the observation unit population of 0.12% (8/6182), with five of eight being classified as unsuspected prior to assignment to observation (0.08% rate).Conclusion: We identified a small number of patients assigned to observation with unsuspected PE. The high rate of hospital admission and prolonged hospital stay suggests that patients with PE are inappropriate for observation status. Given the low incidence of unsuspected PE, there may be a need for a specific approach to screening for PE in observation unit patients.[WestJEM. 2009;10:130-134.

Getting antimalarials on target: impact of national roll-out of malaria rapid diagnostic tests on health facility treatment in three regions of Tanzania.

OBJECTIVES: Parasitological confirmation of malaria prior to treatment is recommended for patients of all ages, with malaria rapid diagnostic tests (mRDTs) an important tool to target artemisinin-based combination therapies (ACTs) to patients with malaria. To evaluate the impact on case management practices of routine government implementation of mRDTs, we conducted large-scale health facility surveys in three regions of Tanzania before and after mRDT roll-out. METHODS: Febrile patients at randomly selected health facilities were interviewed about care received at the facility, and blood samples were collected for reference blood smears. Health facility staff were interviewed about their qualifications and availability of malaria diagnostics and drugs. RESULTS: The percentage of febrile patients tested for malaria at the facility increased from 15.8% in 2010 to 54.9% in 2012. ACTs were obtained by 65.8% of patients positive by reference blood smear in 2010 and by 50.2% in 2012 (P = 0.0675); no antimalarial was obtained by 57.8% of malaria-negative patients in 2010 and by 82.3% in 2012 (P < 0.0001). Overall, ACT use decreased (39.9-21.3%, P < 0.0001) and antibiotic use increased (31.2-48.5%, P < 0.0001). CONCLUSION: Roll-out of mRDTs in Tanzania dramatically improved diagnostic testing for malaria and reduced overuse of ACTs for patients without parasitemia. However, post-roll-out almost 50% of febrile patients did not receive a diagnostic test, and almost 50% of patients testing positive did not receive ACTs. Stock-outs of ACTs and mRDTs were important problems. Further investigation is needed to determine reasons for not providing ACTs to patients with malaria and potential for inappropriate antibiotic use

Road traffic collisions in Malawi: Trends and patterns of mortality on scene

Background: Worldwide, 90% of injury deaths occur in low- and middle-income countries (LMIC). Road traffic collisions (RTCs) are increasingly common and result in more death and disability in the developing world than in the developed world. We aimed to examine the prehospital case fatality rate from RTCs in Malawi.Material and Methods: A retrospective study was performed utilizing the Malawian National Road Safety Council (NRSC) registry from 2008-2012. The NRSC data were collected at the scene by police officers. Victim, vehicle, and environmental factors were used to describe the characteristics of fatal collisions. Case fatality rate was defined as the number of fatalities divided by the number of people involved in RTCs each year. Logistic regression analysis was used to determine predictors of crash scene fatality.Results: A total of 11,467 RTCs were reported by the NRSC between 2008 and 2012. Of these, 34% involved at least one fatality at the scene. The average age of fatalities was 32 years and 82% were male. Drivers of motor vehicles had the lowest odds of mortality following RTCs. Compared to drivers; pedestrians had the highest odds of mortality (OR 39, 95% CI 34, 45) followed by bicyclists (OR 26, 95% CI 22, 31). The average case fatality rate was 17% / year, and showed an increased throughout the study period.Conclusions: RTCs are a common cause of injury in Malawi. Approximately one-third of RTCs involved at least one death at the scene. Pedestrians were particularly vulnerable, exhibiting very high odds of mortality when involved in a road traffic collision. We encourage the use of these data to develop strategies in LMIC countries to protect pedestrians and other road users from RTCs

Effect of direct and indirect transfer status on trauma mortality in sub Saharan Africa

Traumatic injuries account for the greatest portion of global surgical burden particularly in low-and middle-income countries (LMICs). To assess effectiveness of a developing trauma system, we hypothesize that there are survival differences between direct and indirect transfer of trauma patients to a tertiary hospital in sub Saharan Africa