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The conditions that support the simultaneous activity of hydroxyl radicals (OH.) and heterotrophic aerobic bacterial metabolism were investigated using two probe compounds: (1) tetrachloroethene (PCE) for the detection of OH. generated by an iron-nitrilotriacetic acid (Fe-NTA) catalyzed Fenton-like reaction and (2) oxalate (OA) for the detection of heterotrophic metabolism of Xanthobacter flavus. In the absence of the bacterium in the quasi-steady-state Fenton's system, only PCE oxidation was observed; conversely, only OA assimilation was found in non-Fenton's systems containing X. flavus. In combined Fenton's-microbial systems, loss of both probes was observed. PCE oxidation increased and heterotrophic assimilation of OA declined as a function of an increase in the quasi-steady-state H2O2 concentration. Central composite rotatable experimental designs were used to determine the conditions that provide maximum simultaneous abiotic-biotic oxidations, which were achieved with a biomass level of 10(9) CFU/mL, 4.5 mM H2O2, and 2.5 mM Fe-NTA. These results demonstrate that heterotrophic bacterial metabolism can occur in the presence of hydroxyl radicals. Such simultaneous abiotic-biotic oxidations may exist when H2O2 is injected into the subsurface as a microbial oxygen source or as a source of chemical oxidants. In addition, hybrid abiotic-biotic systems could be used for the treatment of waters containing biorefractory organic contaminants present in recycle water, cooling water, or industrial waste streams.

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CONTEXT: Many ambulatory care facilities do not have resources to provide same-day care for all walk-in patients. Yet, there are few guidelines that identify patients for whom care can be safely deferred. OBJECTIVE: To describe the development and implementation of deferred-care guidelines for adults with musculoskeletal complaints. DESIGN: Consensus process and field test. GUIDELINE DEVELOPMENT: After an eight-member multidisciplinary physician panel identified critical factors that necessitate same-day care, we created 34 clinical scenarios to consider for deferred care. In 22 scenarios, the panel members agreed that deferred care was safe. These were formatted into screening guidelines for back, neck, isolated extremity, and generalized muscle pain. IMPLEMENTATION: In reliability testing between two nurses reading 40 patient scenarios, interrater agreement for deferred care was nearly perfect (kappa = 0.95). The guidelines were then applied to 448 patients presenting with musculoskeletal complaints to a Veterans Administration ambulatory care triage station. One hundred seven (24%) patients met guidelines for deferred care. Seventy-six patients agreed to have their care deferred, of which 66 kept their return appointment. CONCLUSIONS: Our guidelines suggest that a substantial proportion of patients with musculoskeletal complaints can have their care deferred. Most patients were willing to do so and kept their follow-up appointment. Use of these guidelines could help decompress ambulatory settings with limited resources to provide nonemergency same-day care.

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STUDY OBJECTIVE: We sought to develop and validate standardized clinical criteria to identify patients presenting to the emergency department whose care may be safely deferred to a later date in a nonemergency setting. METHODS: Using a modified Delphi process, a 17-member multidisciplinary physician panel developed explicit, standardized, deferred-care criteria. In a prospective cohort design, emergency nurses at a tertiary care Veterans Administration (VA) Medical Center, using the criteria, screened 1,187 consecutive ambulatory adult patients presenting with abdominal pain, musculoskeletal symptoms, or respiratory infection symptoms. Patients meeting deferred-care criteria were offered the option of an appointment within 1 week in the ambulatory care clinic at the study site; all other patients were offered same-day care. As outcome measures, we assessed nonelective hospitalizations for related conditions occurring within 7 days of evaluation at our facility or any other VA facility within a 300-mile radius, and we assessed 30-day all-cause mortality. RESULTS: Two hundred twenty-six (19%) patients met screening criteria for deferred care. Patients meeting deferred-care criteria experienced zero (95% confidence interval, 0% to 1.2%) related nonelective VA hospitalizations within 7 days of evaluation, and none died within 30 days. By contrast, 68 (7%) of 961 (95% confidence interval, 5.5% to 8.9%) patients who did not meet deferred-care criteria were hospitalized nonelectively for related conditions, and 5 (0.5%) died. CONCLUSION: By using hospitalization and 30-day mortality as safety gauges, standardized clinical criteria can identify, at presentation, VA ED users who may be safely cared for at a later date in a nonemergency setting. These guidelines apply to a significant proportion of VA ED users with common ambulatory conditions. These criteria deserve testing in other ED settings.

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BACKGROUND: Physicians and nurses often make judgments about the urgency with which patients require evaluation, yet few explicit process-of-care criteria are available to guide these decisions. Using a multidisciplinary expert physician panel and explicit, quantitative group judgment methods, standardized, clinically detailed deferred care criteria were developed to guide emergency department and ambulatory care triage decisions for same-day versus deferred care for patients with respiratory infection symptoms. METHODS: Using a modified Delphi process, an eight-member multidisciplinary expert physician panel rated the safety of deferred care for standardized clinical scenarios. The ratings were converted into explicit criteria and then compared with usual implicit judgment in terms of nurse triage times. RESULTS: The panel achieved 100% consensus on 36 critical clinical factors, each of which precludes deferring care for a patient with respiratory infection symptoms. Based on combinations of 12 additional clinical factors, 48 clinical scenarios were created that the panel rated for deferred care safety. Panelists' ratings agreed for 90% of clinical scenarios. These were formatted into screening criteria. Near-perfect interrater agreement (kappa = 0.9) was found in reproducibility testing. The difference in mean nurse triage times using the criteria compared with implicit nurse judgment was 0.4 minutes (95% confidence interval = -2.1 to 2.9 minutes). CONCLUSIONS: Application of explicit criteria for deferring care of patients with respiratory infection symptoms did not lengthen triage time. This approach may facilitate more efficient resource management for ambulatory settings. However, widespread use before these criteria's, our systematic criteria-based triage should be validated in multicenter clinical trials against an outcome standard and the more common implicit approach.

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Although results obtained with the Tadoma method of speechreading have set a new standard for tactual speech communication, they are nevertheless inferior to those obtained in the normal auditory domain. Speech reception through Tadoma is comparable to that of normal-hearing subjects listening to speech under adverse conditions corresponding to a speech-to-noise ratio of roughly 0 dB. The goal of the current study was to demonstrate improvements to speech reception through Tadoma through the use of supplementary tactual information, thus leading to a new standard of performance in the tactual domain. Three supplementary tactual displays were investigated: (a) an articulatory-based display of tongue contact with the hard palate; (b) a multichannel display of the short-term speech spectrum; and (c) tactual reception of Cued Speech. The ability of laboratory-trained subjects to discriminate pairs of speech segments that are highly confused through Tadoma was studied for each of these augmental displays. Generally, discrimination tests were conducted for Tadoma alone, the supplementary display alone, and Tadoma combined with the supplementary tactual display. The results indicated that the tongue-palate contact display was an effective supplement to Tadoma for improving discrimination of consonants, but that neither the tongue-palate contact display nor the short-term spectral display was highly effective in improving vowel discriminability. For both vowel and consonant stimulus pairs, discriminability was nearly perfect for the tactual reception of the manual cues associated with Cued Speech. Further experiments on the identification of speech segments were conducted for Tadoma combined with Cued Speech. The observed data for both discrimination and identification experiments are compared with the predictions of models of integration of information from separate sources.

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