Changes to Echocardiography-Derived Left Ventricular Filling Pressures and Cardiac Output in Response to Fluid Boluses in Elderly Patients with Left Ventricular Diastolic Dysfunction Undergoing Vascular Surgery

Left ventricular diastolic dysfunction (LVDD) of the heart is a condition where the heart does not relax properly. This condition is important during times of stress, as LVDD is associated with significant morbidity of elderly surgical patients. LVDD is often asymptomatic and unrecognized as many of these patients have normal ejection fractions. However, LVDD may lead to heart failure in patients with preserved systolic function, with the incidence being as high as 50% in hospitalized elderly patients. The diagnosis of LVDD is an independent risk factor for postoperative major adverse cardiac events (MACE) and negatively impacts post-surgery readmission rates. Anesthesiologists play a critical role in the care of elderly patients by managing fluid therapy during surgery. Current standard of care is to manage elderly patients with LVDD using only blood pressure monitoring. Unfortunately blood pressure monitoring is unable to detect changes in diastolic function, which fluid administration may affect. In contrast, transesophageal echocardiography (TEE) can easily measure diastolic function in real-time in the operating rooms. No current studies, however, have assessed changes to diastolic function in response to fluid boluses during noncardiac surgery. Therefore, it is important to serially evaluate LVDD intraoperatively with TEE and determine if changes in anesthetic management, specifically the response to fluid boluses, has effects on diastolic indices. The specific aim of this study is evaluate changes in left ventricular filling pressures and cardiac output in response to fluid boluses during the perioperative period. We predict echocardiographic diastolic indices are influenced by intraoperative fluid administration

Robot Tracking of Human Subjects in Field Environments

Future planetary exploration will involve both humans and robots. Understanding and improving their interaction is a main focus of research in the Intelligent Systems Branch at NASA's Johnson Space Center. By teaming intelligent robots with astronauts on surface extra-vehicular activities (EVAs), safety and productivity can be improved. The EVA Robotic Assistant (ERA) project was established to study the issues of human-robot teams, to develop a testbed robot to assist space-suited humans in exploration tasks, and to experimentally determine the effectiveness of an EVA assistant robot. A companion paper discusses the ERA project in general, its history starting with ASRO (Astronaut-Rover project), and the results of recent field tests in Arizona. This paper focuses on one aspect of the research, robot tracking, in greater detail: the software architecture and algorithms. The ERA robot is capable of moving towards and/or continuously following mobile or stationary targets or sequences of targets. The contributions made by this research include how the low-level pose data is assembled, normalized and communicated, how the tracking algorithm was generalized and implemented, and qualitative performance reports from recent field tests

Cost-Effectiveness of Malaria Diagnosis in Sub-Saharan Africa: The Role of Rapid Diagnostic Tests. Report submitted to WHO

Objective To evaluate the relative cost-effectiveness in different sub-Saharan African settings of presumptive treatment, field-standard microscopy and rapid diagnostic tests (RDTs) to diagnose malaria. Methods We used a decision tree model and probabilistic sensitivity analysis applied to outpatients presenting at rural health facilities with suspected malaria. Costs and effects encompassed those for both patients positive on RDT (assuming artemisinin-based combination therapy) and febrile patients negative on RDT (assuming antibiotic treatment). Interventions were defined as cost-effective if they were less costly and more effective or had an incremental cost per disability-adjusted life year averted of less than US$ 150. Data were drawn from published and unpublished sources, supplemented with expert opinion. Findings RDTs were cost-effective compared with presumptive treatment up to high prevalences of Plasmodium falciparum parasitaemia. Decision-makers can be at least 50% confident of this result below 81% malaria prevalence, and 95% confident below 62% prevalence, a level seldom exceeded in practice. RDTs were more than 50% likely to be cost-saving below 58% prevalence. Relative to microscopy, RDTs were more than 85% likely to be cost-effective across all prevalence levels, reflecting their expected better accuracy under real-life conditions. Results were robust to extensive sensitivity analysis. The cost-effectiveness of RDTs mainly reflected improved treatment and health outcomes for non-malarial febrile illness, plus savings in antimalarial drug costs. Results were dependent on the assumption that prescribers used test results to guide treatment decisions. Conclusion RDTs have the potential to be cost-effective in most parts of sub-Saharan Africa. Appropriate management of malaria and non-malarial febrile illnesses is required to reap the full benefits of these tests

ECONOMIC EVALUATION OF THE COSTS AND COST-EFFECTIVENESS OF THE DIARRHEA ALLEVIATION THROUGH ZINC AND ORAL REHYDRATION THERAPY PROGRAM AT SCALE IN GUJARAT, INDIA

Problem: Diarrhea is the third leading killer of young children, with India bearing the largest national burden. Effective and low-cost treatment is available through oral rehydration salts and zinc supplementation, and trial based literature suggests that these interventions are cost-effective. However, coverage of these interventions remains low, and strategies are being developed for scaling them up. It is less certain whether this health systems strategy is cost-effective at scale, or what economic impact it will have on caregivers. This dissertation evaluates the Diarrhea Alleviation through Zinc and ORS Treatment (DAZT) program in rural Gujarat India in terms of impact on caregiver costs, cost-effectiveness, and cost-effectiveness of different bundles of diarrhea and pneumonia prevention and treatment interventions. Methods: The influence of factors on the odds and amount of economic costs to caregivers was evaluated with a two part model. Due to the non-randomized study design, a net-benefit regression approach was used to evaluate cost-effectiveness while controlling for covariates. Cost-effectiveness of bundled services was evaluated with a mathematical model using probabilistic sensitivity analysis to evaluate uncertainty, and the Lives Saved Tool to project the number of deaths averted over five years. Results: The DAZT program was not associated with a change in odds of incurring an economic cost, although was associated with a $2.12 lower amount spent controlling for covariates. While a 14% to 11% reduction in diarrhea prevalence was observed, it is difficult to infer causality due to study design limitations. Estimates of cost-effectiveness were highly dependent on covariates included, never achieving 95% certainty in the fully specified model. The cost-effectiveness of the program bundled with other services was favorable relative to a ceiling ratio of per capita Gross National Income. Conclusions: It is inconclusive whether the DAZT intervention is a good investment in rural Gujarat based on its impact on diarrhea outcomes, although was cost saving to caregivers. With investment decisions based on expected values of the data taken at face value, the program is recommended in terms of cost-effectiveness. Zinc and oral rehydration salts may be bundled with other services, while maintaining cost-effectiveness

Public Health and Policy Issues of Hernia Surgery in Africa

Abstract Inguinal hernia repair has been overlooked as a public health priority in Africa, with its high prevalence largely unrecognized, and traditional public health viewpoints assuming that not enough infrastructure, human resources, or financing capacity are available for effective service provision. Emerging evidence suggests that inguinal hernias in Ghana are approximately ten times as prevalent as in high-income countries, are much more longstanding and severe, and can be repaired with low-cost techniques using mosquito net mesh through international collaboration. Outcomes from surgery are comparable to published literature, and potential exists for scaling up capacity. Special attention must be paid to creating financing systems that encourage eventual local selfsustainability

Cost-effectiveness analysis of introducing RDTs for malaria diagnosis as compared to microscopy and presumptive diagnosis in central and peripheral public health facilities in Ghana.

Cost-effectiveness information on where malaria rapid diagnostic tests (RDTs) should be introduced is limited. We developed incremental cost-effectiveness analyses with data from rural health facilities in Ghana with and without microscopy. In the latter, where diagnosis had been presumptive, the introduction of RDTs increased the proportion of patients who were correctly treated in relation to treatment with antimalarials, from 42% to 65% at an incremental societal cost of Ghana cedis (GHS)12.2 (US$8.3) per additional correctly treated patients. In the "microscopy setting" there was no advantage to replacing microscopy by RDT as the cost and proportion of correctly treated patients were similar. Results were sensitive to a decrease in the cost of RDTs, which cost GHS1.72 (US$1.17) per test at the time of the study and to improvements in adherence to negative tests that was just above 50% for both RDTs and microscopy

Time To Move from Presumptive Malaria Treatment to Laboratory-Confirmed Diagnosis and Treatment in African Children with Fever

Background to the debate: Current guidelines recommend that all fever episodes in African children be treated presumptively with antimalarial drugs. But declining malarial transmission in parts of sub-Saharan Africa, declining proportions of fevers due to malaria, and the availability of rapid diagnostic tests mean it may be time for this policy to change. This debate examines whether enough evidence exists to support abandoning presumptive treatment and whether African health systems have the capacity to support a shift toward laboratory-confirmed rather than presumptive diagnosis and treatment of malaria in children under five

A cost-effectiveness analysis of provider and community interventions to improve the treatment of uncomplicated malaria in Nigeria: study protocol for a randomized controlled trial.

BACKGROUND: There is mounting evidence of poor adherence by health service personnel to clinical guidelines for malaria following a symptomatic diagnosis. In response to this, the World Health Organization (WHO) recommends that in all settings clinical suspicion of malaria should be confirmed by parasitological diagnosis using microscopy or Rapid Diagnostic Test (RDT). The Government of Nigeria plans to introduce RDTs in public health facilities over the coming year. In this context, we will evaluate the effectiveness and cost-effectiveness of two interventions designed to support the roll-out of RDTs and improve the rational use of ACTs. It is feared that without supporting interventions, non-adherence will remain a serious impediment to implementing malaria treatment guidelines. METHODS/DESIGN: A three-arm stratified cluster randomized trial is used to compare the effectiveness and cost-effectiveness of: (1) provider malaria training intervention versus expected standard practice in malaria diagnosis and treatment; (2) provider malaria training intervention plus school-based intervention versus expected standard practice; and (3) the combined provider plus school-based intervention versus provider intervention alone. RDTs will be introduced in all arms of the trial. The primary outcome is the proportion of patients attending facilities that report a fever or suspected malaria and receive treatment according to malaria guidelines. This will be measured by surveying patients (or caregivers) as they exit primary health centers, pharmacies, and patent medicine dealers. Cost-effectiveness will be presented in terms of the primary outcome and a range of secondary outcomes, including changes in provider and community knowledge. Costs will be estimated from both a societal and provider perspective using standard economic evaluation methodologies. TRIAL REGISTRATION: Clinicaltrials.gov NCT01350752

Cost-Effectiveness of Pre-Referral Antimalarial, Antibacterial, and Combined Rectal Formulations for Severe Febrile Illness

BACKGROUND: Malaria and bacterial infections account for most infectious disease deaths in developing countries. Prompt treatment saves lives, but rapid deterioration often prevents the use of oral therapies; delays in reaching health facilities providing parenteral interventions are common. Rapidly and reliably absorbed antimalarial/antibacterial rectal formulations used in the community could prevent deaths and disabilities. Rectal antimalarial treatments are currently available; rectal antibacterial treatments are yet to be developed. Assessment of the likely cost-effectiveness of these interventions will inform research priorities and implementation. METHODS AND FINDINGS: The burden of malaria and bacterial infections worldwide and in Sub-Saharan and Southern Africa (SSA) and South and South-East Asia (SEA) was summarised using published data. The additional healthcare costs (USD) per death and per Disability Adjusted Life Year (DALY) avoided following pre-referral treatment of severe febrile illness with rectal antimalarials, antibacterials or combined antimalarial/antibacterials in populations at malaria risk in SSA/SEA were assessed. 46 million severe malaria and bacterial infections and 5 million deaths occur worldwide each year, mostly in SSA/SEA. At annual delivery costs of 0.02 dollars/capita and 100% coverage, rectal antimalarials (2 dollars per dose) would avert 240,000 deaths in SSA and 7,000 deaths in SEA at 5 and 177 dollars per DALY avoided, respectively; rectal antibacterials (2 dollars per dose) would avert 130,000 deaths in SSA and 27,000 deaths in SEA at 19 and 97 dollars per DALY avoided, respectively. Combined rectal formulations (2.50 dollars per dose) would avert 370,000 deaths in SSA and 33,000 deaths in SEA at 8 and 79 dollars per DALY avoided, respectively, and are a cost-effective alternative to rectal antimalarials or antibacterials alone. CONCLUSIONS: Antimalarial, antibacterial and combined rectal formulations are likely to be cost-effective interventions for severe febrile illness in the community. Attention should focus on developing effective rectal antibacterials and ensuring that these lifesaving treatments are used in a cost-effective manner

Presumptive treatment of fever cases as malaria: help or hindrance for malaria control?

BACKGROUND: Malaria incidence has been reported to be falling in several countries in sub-Saharan Africa in recent years. This fall appears to have started before the widespread introduction of insecticide-treated nets. In the new era of calls to eliminate and eradicate malaria in sub-Saharan Africa, exploring possible causes for this fall seem pertinent. PRESENTATION OF THE HYPOTHESIS: The authors explore an argument that presumptive treatment of fever cases as malaria may have played a role in reducing transmission of malaria by the prophylactic effect of antimalarials and their widespread use. This strategy, which is already in practise is termed Opportunistic Presumptive Treatment (OPT). TESTING THE HYPOTHESIS: Further comparison of epidemiological indicators between areas with OPT and more targeted treatment is required. If data suggest a benefit of OPT, combining long acting antimalarials that have an anti-gametocyticidal activity component plus using high levels of vector control measures may reduce transmission, prevent resistant strains spreading and be easily implemented. IMPLICATIONS OF THE HYPOTHESIS: OPT is practised widely by presumptive treatment of fever in health facilities and home management of fever. Improving diagnosis using rapid diagnostic tests and thus reducing the number of doses of antimalarials given may have counter intuitive effects on transmission in the context of elimination of malaria in high to moderate transmission settings