Oropharyngeal Lesion in a 7-Year-Old Girl

A 7-year-old girl was referred to the otolaryngology clinic for a left pharyngeal lesion noted 18 months prior. What is your diagnosis?

Person-Centered Sexual Expression: Determining Preferences of Future Nursing Home Residents

BACKGROUND AND OBJECTIVES

Approaches to sexual expression in nursing homes are often devoid of person-centered components, such as resident choice. Little is known about residents' preferences for sexual and intimate expression across different situations. To evaluate future resident preferences, a convenience sample of 389 midlife and older adults in the United States were assessed for their perceptions of appropriateness of sexual and intimate activity among couples in nursing homes, given certain situational factors (e.g., cognitive impairment, relationship status, assent behaviors).

RESEARCH DESIGN AND METHODS

A randomized experimental vignette design was implemented to determine situational factors that influence future resident preferences for sexual expression in nursing homes. Data were analyzed via multilevel modeling, allowing for multiple vignette ratings to be nested among respondents.

RESULTS

Behavioral indications of assent, level of intimacy between the couple, and age of respondent affected respondents' ratings of appropriateness of sexual and intimate activities. Also, cognition and relationship levels interacted for more nuanced effects on activity appropriateness.

DISCUSSION AND IMPLICATIONS

Future resident preferences are often incongruent with attitudes and common practices for approaching sexual expression in nursing home settings. This marks a unique opportunity for person-centered policy development and implementation in the realm of sexual expression.

Rapid characterization of folding and binding interactions with thermolabile ligands by DSC

Differential scanning calorimetry (DSC) is a powerful technique for measuring tight biomolecular interactions. However, many pharmaceutically relevant ligands are chemically unstable at the high temperatures used in DSC analyses. Thus, measuring binding interactions is challenging because the concentrations of ligands and thermally-converted products are constantly changing within the calorimeter cell. Using experimental data for two DNA aptamers that bind to the thermolabile ligand cocaine, we present a new global fitting analysis that yields the complete set of folding and binding parameters for the initial and final forms of the ligand from a pair of DSC experiments, while accounting for the thermal conversion. Furthermore, we show that the rate constant for thermolabile ligand conversion may be obtained with only one additional DSC dataset.

Diagnostic Laryngeal Electromyography: The Wake Forest Experience 1995–1999

BACKGROUND:

Laryngeal electromyography (LEMG) is a valuable diagnostic/prognostic test for patients with suspected laryngeal neuromuscular disorders.

OBJECTIVE:

To report our experience with diagnostic LEMG at the Center for voice Disorders of Wake Forest University and to evaluate the impact of LEMG on clinical management.

METHODS:

Retrospective chart review of 415 patients who underwent diagnostic LEMG over a 5-year period (1995–1999).

RESULTS:

Of 415 studies, 83% (346 of 415) were abnormal, indicating a neuropathic process. LEMG results altered the diagnostic evaluation (eg, the type of radiographic imaging) in 11% (46 of 415) of the patients. Unexpected LEMG findings (eg, contralateral neuropathy) were found in 26% (107 of 415) of the patients, and LEMG results differentiated vocal fold paralysis from fixation in 12% (49 of 415). Finally, LEMG results altered the clinical management (eg, changed the timing and/or type of surgical procedure) in 40% (166 of 415) of the patients.

CONCLUSIONS:

LEMG is a valuable diagnostic test that aids the clinician in the diagnosis and management of laryngeal neuromuscular disorders.

Adapting machine learning techniques to censored time-to-event health record data: A general-purpose approach using inverse probability of censoring weighting

Models for predicting the probability of experiencing various health outcomes or adverse events over a certain time frame (e.g., having a heart attack in the next 5years) based on individual patient characteristics are important tools for managing patient care. Electronic health data (EHD) are appealing sources of training data because they provide access to large amounts of rich individual-level data from present-day patient populations. However, because EHD are derived by extracting information from administrative and clinical databases, some fraction of subjects will not be under observation for the entire time frame over which one wants to make predictions; this loss to follow-up is often due to disenrollment from the health system. For subjects without complete follow-up, whether or not they experienced the adverse event is unknown, and in statistical terms the event time is said to be right-censored. Most machine learning approaches to the problem have been relatively ad hoc; for example, common approaches for handling observations in which the event status is unknown include (1) discarding those observations, (2) treating them as non-events, (3) splitting those observations into two observations: one where the event occurs and one where the event does not. In this paper, we present a general-purpose approach to account for right-censored outcomes using inverse probability of censoring weighting (IPCW). We illustrate how IPCW can easily be incorporated into a number of existing machine learning algorithms used to mine big health care data including Bayesian networks, k-nearest neighbors, decision trees, and generalized additive models. We then show that our approach leads to better calibrated predictions than the three ad hoc approaches when applied to predicting the 5-year risk of experiencing a cardiovascular adverse event, using EHD from a large U.S. Midwestern healthcare system.

Use of an explicit rule decreases procrastination in university students

The procrastination behavior of students from a small rural university was decreased by presenting them with a rule indicating that a sooner final due date for a writing assignment would be contingent on procrastination during earlier phases of the paper. A counterbalanced AB BA design was used to measure the effects of the rule-based treatment across 2 introductory psychology classes (N = 33). Overall, participants engaged in less procrastination, missed fewer deadlines, and produced higher quality writing in the treatment condition.

A Naive Bayes machine learning approach to risk prediction using censored, time-to-event data

Predicting an individual's risk of experiencing a future clinical outcome is a statistical task with important consequences for both practicing clinicians and public health experts. Modern observational databases such as electronic health records provide an alternative to the longitudinal cohort studies traditionally used to construct risk models, bringing with them both opportunities and challenges. Large sample sizes and detailed covariate histories enable the use of sophisticated machine learning techniques to uncover complex associations and interactions, but observational databases are often 'messy', with high levels of missing data and incomplete patient follow-up. In this paper, we propose an adaptation of the well-known Naive Bayes machine learning approach to time-to-event outcomes subject to censoring. We compare the predictive performance of our method with the Cox proportional hazards model which is commonly used for risk prediction in healthcare populations, and illustrate its application to prediction of cardiovascular risk using an electronic health record dataset from a large Midwest integrated healthcare system.

Educating resident physicians using virtual case-based simulation improves diabetes management: a randomized controlled trial

PURPOSE

To test a virtual case-based Simulated Diabetes Education intervention (SimDE) developed to teach primary care residents how to manage diabetes.

METHOD

Nineteen primary care residency programs, with 341 volunteer residents in all postgraduate years (PGY), were randomly assigned to a SimDE intervention group or control group (CG). The Web-based interactive educational intervention used computerized virtual patients who responded to provider actions through programmed simulation models. Eighteen distinct learning cases (L-cases) were assigned to SimDE residents over six months from 2010 to 2011. Impact was assessed using performance on four virtual assessment cases (A-cases), an objective knowledge test, and pre-post changes in self-assessed diabetes knowledge and confidence. Group comparisons were analyzed using generalized linear mixed models, controlling for clustering of residents within residency programs and differences in baseline knowledge.

RESULTS

The percentages of residents appropriately achieving A-case composite clinical goals for glucose, blood pressure, and lipids were as follows: A-case 1: SimDE = 21.2%, CG = 1.8%, P = .002; A-case 2: SimDE = 15.7%, CG = 4.7%, P = .02; A-case 3: SimDE = 48.0%, CG = 10.4%, P < .001; and A-case 4: SimDE = 42.1%, CG = 18.7%, P = .004. The mean knowledge score and pre-post changes in self-assessed knowledge and confidence were significantly better for SimDE group than CG participants.

CONCLUSIONS

A virtual case-based simulated diabetes education intervention improved diabetes management skills, knowledge, and confidence for primary care residents.

Personalised physician learning intervention to improve hypertension and lipid control: randomised trial comparing two methods of physician profiling

PURPOSE

To assess the impact of personalised physician learning (PPL) interventions using simulated learning cases on control of hypertension and dyslipidaemia in primary care settings.

METHODS

A total of 132 primary care physicians, 4568 eligible patients with uncontrolled hypertension, and 15 392 eligible patients with uncontrolled dyslipidaemia were cluster-randomised to one of three conditions: (a) no intervention, (b) PPL-electronic medical record (EMR) intervention in which 12 PPL cases were assigned to each physician based on observed patterns of care in the EMR in the previous year, or (c) PPL-ASSESS intervention in which 12 PPL cases were assigned to each physician based on their performance on four standardised assessment cases. General and generalised linear mixed models were used to account for clustering and to model differences in patient outcomes in the study arms.

RESULTS

Among patients with uncontrolled hypertension at baseline, 49.1%, 46.6% and 47.3% (p=0.43) achieved blood pressure (BP) targets at follow-up. Among patients with uncontrolled dyslipidaemia at baseline, 37.5%, 37.3% and 38.1% (p=0.72) achieved low density lipoprotein cholesterol targets at follow-up in PPL-EMR, PPL-ASSESS and the control group, respectively. Although systolic (BP) (p<0.001) and lipid (p<0.001) values significantly improved during the study, the group-by-time interaction term showed no differential change in systolic BP values (p=0.51) or lipid values (p=0.61) among the three study arms. No difference in intervention effect was noted when comparing the PPL-EMR with the PPL-ASSESS intervention (p=0.47).

CONCLUSIONS

The two PPL interventions tested in this study did not lead to improved control of hypertension or dyslipidaemia in primary care clinics during a mean 14-month follow-up period. This null result may have been due in part to substantial overall improvement in BP and lipid control at the study sites during the study.

TRIAL REGISTRATION NUMBER

NCT00903071.

A Machine Learning Approach to Improving Dynamic Decision Making

Decision strategies in dynamic environments do not always succeed in producing desired outcomes, particularly in complex, ill-structured domains. Information systems often capture large amounts of data about such environments. We propose a domain-independent, iterative approach that (a) applies data mining classification techniques to the collected data in order to discover the conditions under which dynamic decision-making strategies produce undesired or suboptimal outcomes and (b) uses this information to improve the decision strategy under these conditions. In this paper, we formally develop this approach and illustrate it by providing detailed examples of its application to a chronic disease care problem in a healthcare management organization, specifically the treatment of patients with type 2 diabetes mellitus. In particular, the proposed iterative approach is used to improve treatment strategies by predicting and eliminating treatment failures, i.e., insufficient or excessive treatment actions, based on information that is available in electronic medical record systems. We also apply the proposed approach to a manufacturing task, resulting in substantial decision strategy improvements, which further demonstrates the generality and flexibility of the proposed approach.

Cost-effectiveness of an electronic medical record based clinical decision support system

BACKGROUND AND OBJECTIVE

Medical groups have invested billions of dollars in electronic medical records (EMRs), but few studies have examined the cost-effectiveness of EMR-based clinical decision support (CDS). This study examined the cost-effectiveness of EMR-based CDS for adults with diabetes from the perspective of the health care system.

DATA SOURCES/SETTING

Clinical outcome and cost data from a randomized clinical trial of EMR-based CDS were used as inputs into a diabetes simulation model. The simulation cohort included 1,092 patients with diabetes with A1c above goal at baseline.

STUDY DESIGN

The United Kingdom Prospective Diabetes Study Outcomes Model, a validated simulation model of diabetes, was used to evaluate remaining life years, quality-adjusted life years (QALYs), and health care costs over patient lifetimes (40-year time horizon) from the health system perspective.

PRINCIPAL FINDINGS

Patients in the intervention group had significantly lowered A1c (0.26 percent, p = .014) relative to patients in the control arm. Intervention costs were $120 (SE = 45) per patient in the first year and $76 (SE = 45) per patient in the following years. In the base case analysis, EMR-based CDS increased lifetime QALYs by 0.04 (SE = 0.01) and increased lifetime costs by $112 (SE = 660), resulting in an incremental cost-effectiveness ratio of $3,017 per QALY. The cost-effectiveness of EMR-based CDS persisted in one-way, two-way, and probabilistic sensitivity analyses.

CONCLUSIONS

Widespread adoption of sophisticated EMR-based CDS has the potential to modestly improve the quality of care for patients with chronic conditions without substantially increasing costs to the health care system.

Effect of roasting on the allergenicity of major peanut allergens Ara h 1 and Ara h 2/6: the necessity of degranulation assays

BACKGROUND

Peanuts are often consumed after roasting, a process that alters the three-dimensional structure of allergens and leads to Maillard modification. Such changes are likely to affect their allergenicity.

OBJECTIVE

We aimed to establish the effect of thermal treatment mimicking the roasting process on the allergenicity of Ara h 1 and a mix of 2S albumins from peanut (Ara h 2/6).

METHODS

Ara h 1 and Ara h 2/6 were purified from raw peanuts and heated in a dry form for 20 min at 145°C in the presence (R+g) or absence (R-g) of glucose, and soluble proteins were then extracted. Sera obtained from 12 well-characterized peanut-allergic patients were used to assess the IgE binding and degranulation capacities of the allergens.

RESULTS

Extensive heating at low moisture resulted in the hydrolysis of both Ara h 1 and Ara h 2/6. However, in contrast to Ara h 2/6, soluble R+g Ara h 1 formed large aggregates. Although the IgE-binding capacity of R+g and R-g Ara h 1 was decreased 9000- and 3.6-fold, respectively, compared with native Ara h 1, their capacity to elicit mediator release was increased. Conversely, both the IgE-binding capacity and the degranulation capacity of R-g Ara h 2/6 were 600-700-fold lower compared with the native form, although the presence of glucose during heating significantly moderated these losses.

CONCLUSIONS AND CLINICAL RELEVANCE

Extensive heating reduced the degranulation capacity of Ara h 2/6 but significantly increased the degranulation capacity of Ara h 1. This observation can have important ramifications for component-resolved approaches for diagnosis and demonstrates the importance of investigating the degranulation capacity in addition to IgE reactivity when assessing the effects of food processing on the allergenicity of proteins.

Impact of electronic health record clinical decision support on diabetes care: a randomized trial

PURPOSE

We wanted to assess the impact of an electronic health record-based diabetes clinical decision support system on control of hemoglobin A(1c) (glycated hemoglobin), blood pressure, and low-density lipoprotein (LDL) cholesterol levels in adults with diabetes.

METHODS

We conducted a clinic-randomized trial conducted from October 2006 to May 2007 in Minnesota. Included were 11 clinics with 41 consenting primary care physicians and the physicians' 2,556 patients with diabetes. Patients were randomized either to receive or not to receive an electronic health record (EHR)-based clinical decision support system designed to improve care for those patients whose hemoglobin A(1c), blood pressure, or LDL cholesterol levels were higher than goal at any office visit. Analysis used general and generalized linear mixed models with repeated time measurements to accommodate the nested data structure.

RESULTS

The intervention group physicians used the EHR-based decision support system at 62.6% of all office visits made by adults with diabetes. The intervention group diabetes patients had significantly better hemoglobin A(1c) (intervention effect -0.26%; 95% confidence interval, -0.06% to -0.47%; P=.01), and better maintenance of systolic blood pressure control (80.2% vs 75.1%, P=.03) and borderline better maintenance of diastolic blood pressure control (85.6% vs 81.7%, P =.07), but not improved low-density lipoprotein cholesterol levels (P = .62) than patients of physicians randomized to the control arm of the study. Among intervention group physicians, 94% were satisfied or very satisfied with the intervention, and moderate use of the support system persisted for more than 1 year after feedback and incentives to encourage its use were discontinued.

CONCLUSIONS

EHR-based diabetes clinical decision support significantly improved glucose control and some aspects of blood pressure control in adults with type 2 diabetes.

Simulated physician learning program improves glucose control in adults with diabetes

OBJECTIVE

Inexpensive and standardized methods to deliver medical education to primary care physicians (PCPs) are desirable. Our objective was to assess the impact of an individualized simulated learning intervention on diabetes care provided by PCPs.

RESEARCH DESIGN AND METHODS

Eleven clinics with 41 consenting PCPs in a Minnesota medical group were randomized to receive or not receive the learning intervention. Each intervention PCP was assigned 12 simulated type 2 diabetes cases that took about 15 min each to complete. Cases were designed to remedy specific physician deficits found in their electronic medical record observed practice patterns. General linear mixed models that accommodated the cluster randomized study design were used to assess patient-level change from preintervention to 12-month postintervention of A1C, blood pressure, and LDL cholesterol. The relationship between the study arm and the total of intervention and patient health care costs was also analyzed.

RESULTS

Intervention clinic patients with baseline A1C >or=7% significantly improved glycemic control at the last postintervention A1C measurement, intervention effect of -0.19% mean A1C (P = 0.034) and +6.7% in A1C <7% goal achievement (P = 0.0099). Costs trended lower, with the cost per patient -$71 (SE = 142, P = 0.63) relative to nonintervention clinic patients. The intervention did not significantly improve blood pressure or LDL control. Models adjusting for age, sex, and comorbidity showed similar results. PCPs reported high satisfaction.

CONCLUSIONS

A brief individualized case-based simulated learning intervention for PCPs led to modest but significant glucose control improvement in adults with type 2 diabetes without increasing costs.

Is there a downside to customizing care? Implications of general and patient-specific treatment strategies

RATIONALE, AIMS AND OBJECTIVES

The use of general clinical guidelines versus customization of patient care presents a dilemma for clinicians managing chronic illness. The objective of this project is to investigate the claim that the performance of customized strategies for the management of chronic illness depends on accurate patient categorization, and inaccurate categorization can lead to worse performance than that achievable using a general clinical guideline.

METHODS

This paper is based on an analysis of a basic utility model that differentiates between the use of general management strategies and customized strategies.

RESULTS

The analysis identifies necessary conditions for preferring general strategies to customized strategies as a trade-off between strategy performance and the probability of correct patient categorization. The analysis shows that customized treatment strategies developed under optimal conditions are not necessarily preferred.

CONCLUSIONS

Results of the analysis have four implications regarding the design and use of clinical guidelines and customization of care: (i) the balance between the applications of more general strategies versus customization depends on the specificity and accuracy of the strategies; (ii) adoption of clinical guidelines may be stifled as the complexity of guidelines increases to account for growing evidence; (iii) clinical inertia (i.e. the failure to intensify an indicated treatment) can be a rational response to strategy specificity and the probability of misapplication; and, (iv) current clinical guidelines and other decision-support tools may be improved if they accommodate the need for customization of strategies for some patients while providing support for proper categorization of patients.

An innovative continuous flow system for monitoring heavy metal pollution in water using transgenic Xenopus laevis tadpoles

While numerous detection methods exist for environmental heavy metal monitoring, easy-to-use technologies combining rapidity with in vivo measurements are lacking. Multiwell systems exploiting transgenic tadpoles are ideal but require time-consuming placement of individuals in wells. We developed a real-time flow-through system, based on Fountain Flow cytometry, which measures in situ contaminant-induced fluorescence in transgenic amphibian larvae immersed in water samples. The system maintains the advantages of transgenic amphibians, but requires minimal human intervention. Portable and self-contained, it allows on-site measurements. Optimization exploited a transgenic Xenopus laevis bearing a chimeric gene with metal responsive elements fused to eGFP. The transgene was selectively induced by 1 microM Zn(2+). Using this tadpole we show the continuous flow method to be as rapid and sensitive as image analysis. Flow-through readings thus accelerate the overall process of data acquisition and render fluorescent monitoring of tadpoles suitable for on-site tracking of heavy metal pollution.

Customized feedback to patients and providers failed to improve safety or quality of diabetes care: a randomized trial

OBJECTIVE

To assess whether providing customized clinical information to patients and physicians improves safety or quality of diabetes care.

RESEARCH DESIGN AND METHODS

Study subjects included 123 primary care physicians and 3,703 eligible adult diabetic patients with elevated A1C or LDL cholesterol, who were randomly assigned to receive customized feedback of clinical information as follows: 1) patient only, 2) physician only, 3) both the patient and physician, or 4) neither patient nor physician. In the intervention groups, patients received customized mailed information or physicians received printed, prioritized lists of patients with recommended clinical actions and performance feedback. Hierarchical models were used to accommodate group random assignment.

RESULTS

Study interventions did not improve A1C test ordering (P = 0.35) and negatively affected LDL cholesterol test ordering (P < 0.001) in the 12 months postintervention. Interventions had no effect on LDL cholesterol values (P = 0.64), which improved in all groups over time. Interventions had a borderline unfavorable effect on A1C values among those with baseline A1C >or=7% (P = 0.10) and an unfavorable effect on A1C values among those with baseline A1C >or=8% (P < 0.01). Interventions did not reduce risky prescribing events or increase treatment intensification. Time to next visit was longer in all intervention groups compared with that for the control group (P < 0.05).

CONCLUSIONS

Providing customized decision support to physicians and/or patients did not improve quality or safety of diabetes care and worsened A1C control in patients with baseline A1C >or=8%. Future researchers should consider providing point-of-care decision support with redesign of office systems and/or incentives to increase appropriate actions in response to decision-support information.

Simulated physician learning intervention to improve safety and quality of diabetes care: a randomized trial

OBJECTIVE

To assess two physician learning interventions designed to improve safety and quality of diabetes care delivered by primary care physicians (PCPs).

RESEARCH DESIGN AND METHODS

This group randomized clinical trial included 57 consenting PCPs and their 2,020 eligible adult patients with diabetes. Physicians were randomized to no intervention (group A), a simulated case-based physician learning intervention (group B), or the same simulated case-based learning intervention with physician opinion leader feedback (group C). Dependent variables included A1C values, LDL cholesterol values, pharmacotherapy intensification rates in patients not at clinical goals, and risky prescribing events.

RESULTS

Groups B and C had substantial reductions in risky prescribing of metformin in patients with renal impairment (P = 0.03). Compared with groups A and C, physicians in group B achieved slightly better glycemic control (P = 0.04), but physician intensification of oral glucose-lowering medications was not affected by interventions (P = 0.41). Lipid management improved over time (P < 0.001) but did not differ across study groups (P = 0.67).

CONCLUSIONS

A simulated, case-based learning intervention for physicians significantly reduced risky prescribing events and marginally improved glycemic control in actual patients. The addition of opinion leader feedback did not improve the learning intervention. Refinement and further development of this approach is warranted.

Variation in quality of diabetes care at the levels of patient, physician, and clinic

INTRODUCTION

We studied variance in glycated hemoglobin (HbA1c) values among adults with diabetes to identify variation in quality of diabetes care at the levels of patient, physician, and clinic, and to identify which levels contribute the most to variation and which variables at each level are related to quality of diabetes care.

METHODS

Study subjects were 120 primary care physicians and their 2589 eligible adult patients with diabetes seen at 18 clinics. The dependent variable was HbA1c values recorded in clinical databases. Multivariate hierarchical models were used to partition variation in HbA1c values across the levels of patient, physician, or clinic and to identify significant predictors of HbA1c at each level.

RESULTS

More than 95% of variance in HbA1c values was attributable to the patient level. Much less variance was seen at the physician and clinic level. Inclusion of patient and physician covariates did not substantially change this pattern of results. Intensification of pharmacotherapy (t = -7.40, P < .01) and patient age (t = 2.10, P < .05) were related to favorable change in HbA1c. Physician age, physician specialty, number of diabetes patients per physician, patient comorbidity, and clinic assignment did not predict change in HbA1c value. The overall model with covariates explained 11.8% of change in HbA1c value over time.

CONCLUSION

These data suggest that most variance in HbA1c values is attributable to patient factors, although physicians play a major role in some patient factors (e.g., intensification of medication). These findings may lead to more effective care-improvement strategies and accountability measures.

High throughput, real-time detection of Naegleria lovaniensis in natural river water using LED-illuminated Fountain FlowTMCytometry

AIMS

To test Fountain Flow Cytometry (FFC) for the rapid and sensitive detection of Naegleria lovaniensis amoebae (an analogue for Naegleria fowleri) in natural river waters.

METHODS AND RESULTS

Samples were incubated with one of two fluorescent labels to facilitate detection: ChemChrome V6, a viability indicator, and an R-phycoerytherin (RPE) immunolabel to detect N. lovaniensis specifically. The resulting aqueous sample was passed as a stream in front of a light-emitting diode, which excited the fluorescent labels. The fluorescence was detected with a digital camera as the sample flowed toward the imager. Detections of N. lovaniensis were made in inoculated samples of natural water from eight rivers in France and the United States. FFC enumeration yielded results that are consistent with other counting methods: solid-phase cytometry, flow cytometry, and hemocytometry, down to concentrations of 0.06 amoebae ml(-1), using a flow rate of 15 ml min(-1).

CONCLUSIONS

This study supports the efficacy of using FFC for the detection of viable protozoa in natural waters and indicates that use of RPE illuminated at 530 nm and detected at 585 nm provides a satisfactory means of attenuating background.

SIGNIFICANCE AND IMPACT OF THE STUDY

Because of the severe global public health issues with drinking water and sanitation, there is an urgent need to develop a technique for the real-time detection of viable pathogens in environmental samples at low concentrations. FFC addresses this need.

Cost-effective diagnosis of ingested foreign bodies

OBJECTIVES

To compare the cost effectiveness of plain film radiography, computed tomography (CT), and endoscopy as initial diagnostic modalities in adult patients complaining of retained ingested foreign bodies.

DESIGN

A systematic literature review was conducted to determine key statistics for the analysis, such as prevalence of disease, prevalence of complications, and the sensitivity and specificity of each diagnostic modality. Costs were estimated using 2006 Medicare reimbursement for hospital and professional fees. A deterministic cost-effectiveness analysis was then conducted using decision analysis software and a decision tree model to evaluate the various diagnostic strategies. After identifying initial results, we also performed sensitivity and threshold analysis to assess the strength of the recommendations.

RESULTS

We reviewed 316 abstracts, identified 16 pertinent studies that included a total of 7,088 patients with possible foreign bodies, and extracted key statistics from those papers. Decision analysis showed that CT scanning as an initial diagnostic strategy proved more cost effective than plain film or operative endoscopy. The incremental cost of immediate endoscopy for every additional correctly diagnosed patient was $5,238. Plain radiography was more costly and less effective, even with the addition of confirmatory CT scanning after a negative plain film. Sensitivity and threshold analyses demonstrated that these results are robust.

CONCLUSIONS

Patients presenting with a complaint of a retained ingested foreign body are most cost-effectively managed with CT scan, after history and physical. Immediate endoscopy may be considered if CT is not available, although it adds significant cost. Plain films are dominated by these two diagnostic strategies.

Fountain Flow cytometry, a new technique for the rapid detection and enumeration of microorganisms in aqueous samples

BACKGROUND

Pathogenic microorganisms are known to cause widespread waterborne disease worldwide. There is an urgent need to develop a technique for the real-time detection of pathogens in environmental samples at low concentrations, <10 microorganisms/ml, in large sample volumes, > or =100 ml.

METHODS

A novel method, Fountain Flowtrade mark cytometry, for the rapid and sensitive detection of individual microorganisms in aqueous samples is presented. Each sample is first incubated with a fluorescent label and then passed as a stream in front of a laser, which excites the label. The fluorescence is detected with a CCD imager as the sample flows toward the imager along its optical axis. The feasibility of Fountain Flow cytometry (FFC) is demonstrated by the detection of Escherichia coli labeled with ChemChrome CV6 and SYBR Gold in buffer and natural river water.

RESULTS

Detections of labeled E. coli were made in aqueous suspensions with an efficiency of 96% +/- 14% down to a concentration approximately 200 bacteria/ml.

CONCLUSIONS

The feasibility of FFC is demonstrated by the detection of E. coli in buffer and natural river water. FFC should apply to the detection of a wide range of pathogenic microorganisms including amoebae.

Patient-controlled comparison of flexible endoscopic evaluation of swallowing with sensory testing (FEESST) and videofluoroscopy

OBJECTIVE

The objective of this study was to compare the results of videofluoroscopy (VFS) with flexible endoscopic evaluation of swallowing with sensory testing (FEESST) in dysphagia testing.

METHODS

The authors conducted a retrospective review of data collected over a 4-year period at a tertiary care medical center. The FEESST and VFS results for patients receiving both examinations within a 2-week period were compared with respect to swallowing function. Comparisons were categorized as full agreement, minor disagreement that would not result in a significant difference in diet recommendations, and major disagreement that would result in a significant difference in diet recommendations. Kappa with quadratic weighting was calculated to evaluate the inter-test agreement.

RESULTS

Fifty-four patients met inclusion criteria and were reviewed. Forty-one percent of patients were not eating by mouth at the time of FEESST and the mean interval between the two examinations was 5 days. Laryngeal examination revealed edema/erythema in 93%, impaired pharyngeal squeeze in 66%, decreased laryngopharyngeal sensation in 82%, and absent laryngeal adductor reflex in 30%. FEESST with all consistencies revealed pooling in 89%, penetration in 83%, and aspiration in 65% of patients. VFS revealed pooling in 65%, penetration in 67%, and aspiration in 54% of patients. Comparison of FEESST and VFS revealed full agreement in 52%, minor disagreement in 13%, and major disagreement in 35% of patients. A weighted kappa value of 0.324 signified only "fair" agreement between the two tests.

CONCLUSIONS

FEESST and VFS may not represent comparable tests of dysphagia. Further comparative studies of tests of swallowing function are required to determine the ideal approach to dysphagia testing.

Major aorto-pulmonary collateral arteries (MAPCAs)--Bronchial fistula presenting as tracheotomy bleed

Tracheal hemorrhage is a common occurrence in pediatric patients with long-term tracheotomies. The majority of these events are related to self-limited etiologies, such as granulation tissue or suction trauma. Tracheo-arterial fistula, however, represents a frequently fatal form of tracheal hemorrhage that may initially be difficult to distinguish from other causes. Previous reports have described the pathophysiology, presentation and management of tracheo-arterial fistula involving the innominate artery. We describe a case of a 21-month-old male with a history of significant congenital cardiac malformations and chronic tracheotomy tube dependence who presented with intermittent, brisk bleeding from the tracheotomy tube. He was ultimately diagnosed with and treated for an arterio-bronchial fistula from a major aorto-pulmonary collateral artery. We review the etiology and management of this disorder.

Definitive management of severe facial trauma utilizing free tissue transfer

OBJECTIVE

Severe ballistic or avulsion injuries to the face create complex, composite defects. We report the results of an aggressive management algorithm to optimize facial form and function: (1) the initial encounter, (2) definitive reconstruction with vascularized tissue, and (3) aesthetic and prosthetic refinement.

STUDY DESIGN AND SETTING

Retrospective case series of 49 patients in 2 tertiary care institutions. Patients were evaluated for age, gender, mechanism of injury, anatomic subsites involved, surgical procedures, flaps utilized, complications, and functional outcomes.

RESULTS

Forty defects were gunshot wounds, 9 resulted from major avulsive trauma. Involved sites included 13 oromandibular, 21 midface/upper face, and 15 combined sites; 54 free flaps were utilized, 21 were soft tissue and 33 contained bone. No flap failures occurred. Function and cosmesis were best in the oromandibular only group, and worst in the combined group with nasal and/or orbital tissue loss.

CONCLUSION

Treatment of severe facial trauma requires early tissue debridement with bony repair and/or stenting to minimize scar contracture. Free tissue transfer techniques allow simultaneous reconstruction of the bony framework and overlying tissues. Multiple secondary procedures are frequently required for optimal aesthetic restoration.

EBM RATING

C.

Making improvements in the management of patients with type 2 diabetes: a possible role for the control of variation in glycated hemoglobin

Glucose level varies over time due to a number of complex physiologic processes. Evidence suggests variation in glucose level contributes to risk of complications. The timescale associated with variation in glucose level is on the order of seconds to minutes, yet diabetes complications stem from years of cumulative effects. This difference between timescale suggests a slower timescale may better represent the influential component of variation. We hypothesize variation in glycated hemoglobin captures the component of variation associated with future complications. Moreover, we hypothesize that patient-management strategies influence variation in glycated hemoglobin level. From a systems control perspective, increasing variation may well reflect a policy of closed loop feedback control where changes in patient glycated hemoglobin are addressed after the fact. Such a strategy attends to problems as they arise. In contrast, decreasing variation may result from a clinical strategy that is anticipatory and proactive. A physician using a proactive strategy will base current moves on anticipation of future states, controlling variation in patient outcomes such as glycated hemoglobin. We motivate our discussion using observational data from a large multispecialty medical group in Minnesota: we characterize the within-patient trend and variation of glycated hemoglobin in adults with type 2 diabetes, describe patterns of variation, and identify factors associated with variation. Our hypotheses imply: (1) patterns of variation in glycated hemoglobin reflect physician treatment strategy; (2) variation provides an independent contribution to risk of diabetes complications; (3) the development of treatment strategies that control variation may be a beneficial goal in the management of type 2 diabetes.

A structured review of the effect of economic incentives on consumers' preventive behavior

Improving participation in preventive activities will require finding methods to encourage consumers to engage in and remain in such efforts. This review assesses the effects of economic incentives on consumers' preventive health behaviors. A study was classified as complex preventive health if a sustained behavior change was required of the consumer; if it could be accomplished directly (e.g., immunizations), it was considered simple. A systematic literature review identified 111 randomized controlled trials of which 47 (published between 1966 and 2002) met the criteria for review. The economic incentives worked 73% of the time (74% for simple, and 72% for complex). Rates varied by the goal of the incentive. Incentives that increased ability to purchase the preventive service worked better than more diffuse incentives, but the type matters less than the nature of the incentive. Economic incentives are effective in the short run for simple preventive care, and distinct, well-defined behavioral goals. Small incentives can produce finite changes, but it is not clear what size of incentive is needed to yield a major sustained effect.

Topical nasal anesthesia for transnasal fiberoptic laryngoscopy: a prospective, double-blind, cross-over study

BACKGROUND

Transnasal fiberoptic laryngoscopy (TFL) is frequently performed by otolaryngologists, speech language pathologists, and various other health care providers. Historically, topical sprays have been administered to patients to decongest and anesthetize the nasal mucosa, thus minimizing the discomfort of the procedure. Recently, it was reported that patients undergoing TFL with topical anesthesia experienced no improvement in comfort compared with those who received oxymetazoline or saline. This observation is in direct opposition to our clinical experience that patients tolerate the procedure better with topical anesthesia.

PURPOSE

We sought to compare patient comfort levels during TFL after the administration of cocaine, oxymetazoline, or saline.

METHODS

Fifteen subjects undergoing TFL were prospectively evaluated. Each had TFL performed on 3 separate occasions. Before TFL, each patient received either 4% cocaine, 0.05% oxymetazoline, or saline topically administered via an atomizer to both nasal cavities (1 spray of 2-second duration). By the conclusion of the study, each patient had undergone TFL with each of the test agents. The subjects rated the discomfort they experienced on a scale ranging from 1 (minimal discomfort) to 5 (severe discomfort). Both patient and examiner were blinded to the test agent used.

RESULTS

The mean nasal discomfort score for saline was 2.8 +/- 1.1. The scores for oxymetazoline and cocaine were 3.4 +/- 0.9 and 2.0 +/- 0.9, respectively. Compared with saline and oxymetazoline independently, TFL with topical cocaine appeared to provide more comfort (P < 0.05 and P < 0.005).

CONCLUSION

The continued routine use of topical anesthetics such as cocaine before the performance of TFL is justified because it significantly decreases the patient's discomfort.

Topical Nasal Anesthesia for Transnasal Fiberoptic Laryngoscopy: A Prospective, Double-Blind, Cross-Over Study

BACKGROUND: Transnasal fiberoptic laryngoscopy (TFL) is frequently performed by otolaryngologists, speech language pathologists, and various other health care providers. Historically, topical sprays have been administered to patients to decongest and anesthetize the nasal mucosa, thus minimizing the discomfort of the procedure. Recently, it was reported that patients undergoing TFL with topical anesthesia experienced no improvement in comfort compared with those who received oxymetazoline or saline. This observation is in direct opposition to our clinical experience that patients tolerate the procedure better with topical anesthesia. PURPOSE: We sought to compare patient comfort levels during TFL after the administration of cocaine, oxymetazoline, or saline.

METHODS: Fifteen subjects undergoing TFL were prospectively evaluated. Each had TFL performed on 3 separate occasions. Before TFL, each patient received either 4% cocaine, 0.05% oxymetazoline, or saline topically administered via an atomizer to both nasal cavities (1 spray of 2-second duration). By the conclusion of the study, each patient had undergone TFL with each of the test agents. The subjects rated the discomfort they experienced on a scale ranging from 1 (minimal discomfort) to 5 (severe discomfort). Both patient and examiner were blinded to the test agent used.

RESULTS: The mean nasal discomfort score for saline was 2.8 ± 1.1. The scores for oxymetazoline and cocaine were 3.4 ± 0.9 and 2.0 ± 0.9, respectively. Compared with saline and oxymetazoline independently, TFL with topical cocaine appeared to provide more comfort ( P < 0.05 and P < 0.005). CONCLUSION: The continued routine use of topical anesthetics such as cocaine before the performance of TFL is justified because it significantly decreases the patient's discomfort.

Topical nasal anesthesia and laryngopharyngeal sensory testing: a prospective, double-blind crossover study

Laryngopharyngeal sensory discrimination testing (LPSDT) has become a popular means of detecting sensory deficits in patients with voice and/or swallowing complaints. During this procedure, transnasal fiberoptic laryngoscopy (TFL) using a specialized fiberoptic scope is performed in order to deliver discrete pulses of air to the laryngopharyngeal mucosa. Historically, topical anesthesia has been applied to the nasal mucosa to lessen discomfort during TFL. Because of the concern that topical nasal anesthesia could also anesthetize the laryngopharynx, it is usually not used during sensory testing. To prospectively compare LPSDT scores after the nasal administration of cocaine hydrochloride, oxymetazoline hydrochloride, and saline solution, we prospectively evaluated 15 subjects undergoing LPSDT. Each had the procedure performed on 3 separate occasions. Before examination, each patient was administered either 4% cocaine, 0.05% oxymetazoline, or saline solution by atomizer (2 sprays of 1-second duration to each naris). By the conclusion of the study, each patient had undergone sensory testing with each of the test agents. During each examination, the minimal air pulse eliciting the laryngeal adductor reflex was recorded for both sides of the laryngopharynx. Both patient and examiner were blinded to the test agent used. The mean sensory score for saline solution was 3.9 mm Hg. The sensory scores for oxymetazoline and cocaine were 3.4 and 3.5 mm Hg, respectively. When compared to saline solution and oxymetazoline independently, sensory testing of the laryngopharynx during which the nose was anesthetized with cocaine resulted in similar thresholds for eliciting the laryngeal adductor reflex (p = .40 and p = .85). We conclude that topical anesthesia can be applied to the nasal cavity during LPSDT without altering laryngeal sensation.

Intraparotid facial nerve neurofibromas

OBJECTIVES

To provide an awareness of intraparotid facial nerve neurofibroma as a cause of parotid masses and to describe their characteristics and management considerations.

STUDY DESIGN

Case report with literature review.

METHODS

The medical records of three patients with intraparotid facial nerve neurofibromas are reviewed, and data concerning the patient's presentations, treatment, and disease course are presented with a review of the world's literature on intraparotid facial nerve neurofibromas.

CONCLUSIONS

Tumors arising from the extratemporal course of the facial nerve are quite rare. The tumors arise from Schwann cells and include the schwannoma and the neurofibroma. The overwhelming benign nature of these lesions necessitates a conservative course of treatment. Histological diagnosis should be followed by a limited tumor excision with emphasis on retaining normal facial nerve function. Malignant lesions require wide excision with facial nerve grafting or facial nerve reanimation.

Understanding variation in chronic disease outcomes

We propose an explanation for variation in disease outcomes based on patient adaptation to the conditions of chronic disease. We develop a model of patient adaptation using the example of Type 2 diabetes mellitus and assumptions about the process entailed in transforming self-care behaviors of compliance with treatment, compliance with glucose monitoring, and patient's knowledge seeking behavior into health outcomes of glycemic control and patient satisfaction. Using data from 609 adults with diagnosed Type 2 diabetes we develop an efficiency (fitness) frontier in order to identify best practice (maximally adapted) patients and forms (archetypes) of patient inefficiency. Outcomes of frontier patients are partitioned by categories of returns to scale. Outcomes for off-frontier patients are associated with disease severity and patient archetype. The model implicates strategies for improved health outcomes based on fitness and self-care behaviors.

Are differences in the available aromatase inhibitors and inactivators significant?

Aromatase inhibitors are endocrine agents with a different mode of action than tamoxifen against breast tumors. In postmenopausal women, estrogen concentrations are maintained primarily via aromatase, a cytochrome P-450 enzyme that acts at the final step in the estrogen synthesis pathway. The first clinically available aromatase inhibitor, aminoglutethimide, was introduced for the second-line treatment of advanced breast cancer in the late 1970s. Despite proven efficacy in this setting, its widespread use was limited by its overall toxicity and its lack of selectivity for the aromatase enzyme. This led to the search for novel, more effective, and less toxic aromatase inhibitors. As a result, several aromatase inhibitors with a high degree of selectivity for aromatase and improved tolerability have become clinically available for the treatment of postmenopausal women with advanced breast cancer: (a) anastrozole; (b) letrozole; (c) fadrozole; (d) formestane; and (e) exemestane. Of these, formestane and exemestane are steroidal nonreversible aromatase inhibitors, also known as aromatase inactivators, whereas fadrozole, anastrozole, and letrozole are nonsteroidal reversible aromatase inhibitors. These agents differ in pharmacokinetics, selectivity, and potency, although all are more selective than aminoglutethimide. Some differences in adverse effect profile are also noticeable between and within these two classes of agents. The clinical significance of these differences is not yet evident but may well prove to be relevant in the long-term adjunctive setting.

Ambulatory 24-hour double-probe pH monitoring: the importance of manometry

OBJECTIVE

Historically, manometry has been used for sphincter localization before ambulatory 24-hour double-probe pH monitoring to ensure accurate placement of the probes. Recently, direct-vision placement (DVP), using transnasal fiberoptic laryngoscopy (TFL), has been offered as an alternative technique. Presumably, DVP might be used to precisely place the proximal (pharyngeal) pH probe; however, using DVP, there appears to be no way to accurately position the distal (esophageal) probe. The purpose of this study was to evaluate the accuracy of DVP for pH probe placement using manometric measurement as the gold standard.

METHODS

Thirty patients undergoing pH monitoring participated in this prospective study. Each subject underwent manometric examination of the esophagus to determine the precise location of the upper and lower esophageal sphincters (UES and LES). In addition, external anatomic landmarks were used to estimate interprobe distances. A physician blinded to the manometry results then placed a pH catheter using DVP so that the proximal probe was located just above the UES. The results were recorded and compared with those obtained by manometry.

RESULTS

Accurate DVP of the proximal pH probe was achieved in 70% (23 of 30) of the subjects. The use of external anatomic landmarks to estimate interprobe distance resulted in accurate positioning of the distal probe in only 40% (12 of 30) of the subjects. Using fixed interprobe distances of 15 cm and 20 cm, distal probe position accuracy was 3% (1 of 30) and 40% (12 of 30), respectively. Therefore, using DVP, the distal esophageal probe was in an incorrect position in 60% to 97% of subjects.

CONCLUSION

For double-probe pH monitoring, the proximal probe can be accurately positioned by DVP; however, there is no precise way to determine the interprobe distance required to correctly position the distal pH probe. Failure to accurately position the distal probe results in grossly inaccurate esophageal acid-exposure times. Thus, manometry is needed to ensure valid double-probe pH monitoring data.

Effect of cyclooxygenase-2 inhibitor (celecoxib) on the infarcted heart in situ

Several attempts have been made to replace aspirin with compounds without gastric toxicity; a cyclooxygenase-2 (COX-2) inhibitor, celecoxib, and a nitric oxide-aspirin, NCX-4016, have been developed for this purpose. This paper compares effects of celecoxib, NCX-4016 and aspirin on production of prostacyclin (PGI2) and thromboxane A2 (TXA2) and activation of the inducible form of nitric oxide synthase (iNOS) in infarcted heart in situ. Aspirin was most effective in reducing myocardial PGI2 synthesis and formation of TXA2. Myocardial effects of celecoxib resemble those of NCX-4016, although the two compounds have different modes of action.

Diagnostic laryngeal electromyography: The Wake Forest experience 1995-1999

BACKGROUND

Laryngeal electromyography (LEMG) is a valuable diagnostic/prognostic test for patients with suspected laryngeal neuromuscular disorders.

OBJECTIVE

To report our experience with diagnostic LEMG at the Center for Voice Disorders of Wake Forest University and to evaluate the impact of LEMG on clinical management.

METHODS

Retrospective chart review of 415 patients who underwent diagnostic LEMG over a 5-year period (1995-1999).

RESULTS

Of 415 studies, 83% (346 of 415) were abnormal, indicating a neuropathic process. LEMG results altered the diagnostic evaluation (eg, the type of radiographic imaging) in 11% (46 of 415) of the patients. Unexpected LEMG findings (eg, contralateral neuropathy) were found in 26% (107 of 415) of the patients, and LEMG results differentiated vocal fold paralysis from fixation in 12% (49 of 415). Finally, LEMG results altered the clinical management (eg, changed the timing and/or type of surgical procedure) in 40% (166 of 415) of the patients.

CONCLUSIONS

LEMG is a valuable diagnostic test that aids the clinician in the diagnosis and management of laryngeal neuromuscular disorders.

Real time biodetection of individual pathogenic microorganisms in food and water

The primary objective of this research is to examine the feasibility of using an innovative technique based on laser-induced fluorescence coupled with flow cytometry to detect pathogenic microorganisms in food or water in real time. Our initial application is the rapid detection of E. coli O157:H7 in ground beef. The research performed demonstrated conclusively that this approach is feasible, and that the technique has key advantages over current alternatives including: it is (1) able to totally examine a large volume of food or water in real time, (2) capable of detecting single microorganisms (alternative techniques require in excess of 10(4) microorganisms), (3) intrinsically automatic, and (4) sensitive only to the selected bacteria. We have demonstrated the feasibility of detecting individual E. coli bacteria with a breadboard system. The performance of this system allows for rapid detection of individual specific pathogenic microorganisms. Two of the most significant commercial applications of this technique are the detection of infectious microorganisms in contaminated food and water. Food-borne microbial pathogens account for approximately 7 million illnesses and 9,000 deaths in the U.S. annually, with an estimated economic loss of at least $6 billion [1]. In addition, this method has the potential for a broad range of other commercial applications, including the detection of small numbers of molecules, such as the ultrasensitive detection of explosives and groundwater contaminants.

A mechanism for plus-strand transfer enhancement by the HIV-1 nucleocapsid protein during reverse transcription

The HIV-1 nucleocapsid protein (NC) functions as a nucleic acid chaperone during the plus-strand transfer step in reverse transcription by facilitating annealing of the primer binding site (PBS) sequence in the short plus-strand strong-stop DNA fragment [(+) SSDNA] to a complementary site located near the 3' end of the minus-strand DNA [(-) PBS DNA]. To investigate the mechanism by which NC performs this function, we have prepared an 18-nucleotide (-) PBS DNA for nuclear magnetic resonance (NMR) based structural and NC binding studies. The (-) PBS DNA forms a stable hairpin (T(m) approximately 42 +/- 5 degrees C) that contains a five-residue loop and a bulged thymine in a guanosine-cytosine-rich stem. Addition of substoichiometric amounts of NC results in significant broadening and reductions in NMR signal intensities of the Watson-Crick base-paired imino protons and a reduction by 20 degrees C in the upper temperature at which the imino proton signals are detectable, consistent with destabilization of the structure. The results suggest that inefficient annealing in the absence of NC may be due to the intrinsic stability of an internal (-) PBS DNA hairpin and that NC facilitates strand transfer by destabilizing the hairpin and exposing stem nucleotides for base pairing with the PBS sequence in (+) SSDNA.

Binding site analysis of cellulose binding domain CBD(N1) from endoglucanse C of Cellulomonas fimi by site-directed mutagenesis

Endoglucanase C (CenC), a beta1,4 glucanase from the soil bacterium Cellulomonas fimi, binds to amorphous cellulose via two homologous cellulose binding domains, termed CBD(N1) and CBD(N2). In this work, the contributions of 10 amino acids within the binding cleft of CBD(N1) were evaluated by single site-directed mutations to alanine residues. Each isolated domain containing a single mutation was analyzed for binding to an insoluble amorphous preparation of cellulose, phosphoric acid swollen Avicel (PASA), and to a soluble glucopyranoside polymer, barley beta-glucan. The effect of any given mutation on CBD binding was similar for both substrates, suggesting that the mechanism of binding to soluble and insoluble substrates is the same. Tyrosines 19 and 85 were essential for tight binding by CBD(N1) as their replacement by alanine results in affinity decrements of approximately 100-fold on PASA, barley beta-glucan, and soluble cellooligosaccharides. The tertiary structures of unbound Y19A and Y85A were assessed by heteronuclear single quantum coherence (HSQC) spectroscopy. These studies indicated that the structures of both mutants were perturbed but that all perturbations are very near to the site of mutation.

The effect of aspirin and two nitric oxide donors on the infarcted heart in situ

Nitric oxide (NO) donors are heterogeneous substances which release NO, a biologically active compound. NO released by nitric oxide donors has important effects on the circulation by causing vasodilation, diminishing myocardial contractile force, inhibiting platelet aggregation, and counteracting the effects of thromboxane A2. In the infarcted heart, activation of the inducible form of nitric oxide synthase (iNOS) and the formation of prostacyclin and thromboxane A2 by cyclooxygenase (COX) were increased. Myocardial infarction also resulted in increased myocardial NO production. Aspirin (acetylsalicylic acid. ASA) at low concentration (35 mg/kg/day) fails to change iNOS production, in contrast to higher dose (150 mg/kg/day) which, as previously shown, inhibits iNOS activity. ASA at all doses also suppresses myocardial prostanoid formation because of inhibition of COX. Recently, two NO donors have been synthesized: NCX 4016 and Diethylenetriamine/NO (DETA/NO). NCX 4016 combines an NO-releasing moiety with a carboxylic residue via an esteric bond. We describe here that NCX 4016 (65 mg/kg/day) increased prostacyclin and thromboxane A2 production in the infarcted heart muscle, overcoming the inhibitory effects of ASA. As a result of nitric oxide release, oxidation products of NO (NO2- and NO3-; NOx) in arterial blood rose following administration of NCX 4016. On oral administration, NCX 4016 did not change systemic arterial pressure. The effects of a single NO donor, DETA/NO (1.0 mg/kg/day) on the infarcted heart were also investigated On intravenous administration, the compound increased NO concentration in arterial blood slightly but to a lesser degree than NCX 4016. Like NCX 4016, it raised myocardial production of prostacyclin and thromboxane A2 in the infarcted heart. However, it caused a severe fall in blood pressure. These findings demonstrate that newly-synthesized NO donors release nitric oxide in situ and increase myocardial production of prostanoids. NCX 4016 has therapeutic potential because it can be orally administered, lacks hypotensive effects, increases blood levels of nitric oxide and myocardial prostacyclin production.