Commutable whole blood reference materials for hemoglobin A1c validated on multiple clinical analyzers.

Background The measurement of hemoglobin A1c (HbA1c) is important for diagnosing diabetes mellitus as well as assessing glycemic control in diabetic patients. Commutable whole blood certified reference materials (CRMs) are needed in the measurement of HbA1c for method validation and/or as quality controls. Methods We developed three levels of hemolyzed whole blood CRMs for HbA1c. The certified values were determined using liquid chromatography-isotope dilution tandem mass spectrometry method (LC-IDMS/MS) where two "signature" hexapeptides of HbA1c and hemoglobin A0 (HbA0) were used as the calibration standards. The concentrations of the hexapeptide solutions were determined by amino acid analysis by the LC-IDMS/MS method using amino acid CRMs as the calibration standards. The commutability study was conducted by measuring 25 patient specimens and the whole blood CRMs by both LC-IDMS/MS method and various routine methods using six different clinical analyzers. Results The certified values were determined to be 35.1±2.0, 50.3±1.9 and 65.8±2.6 mmol/mol, respectively. These CRMs showed good commutability on five of the six clinical analyzers but showed poor commutability on one of the clinical analyzers that used similar method as two other analyzers where good commutability was observed. Conclusions With certified target values based on metrological traceability and good commutability on most of the clinical analyzers, the developed whole blood CRMs can be used for method validation or as quality control materials in the measurement of HbA1c. The commutability study results also underscored the need of commutability testing of clinical CRMs using various clinical analyzers.

Clinical and Molecular Epidemiology of Carbapenem-Resistant Enterobacteriaceae Among Adult Inpatients in Singapore.

BACKGROUND: Since 2010, the incidence of carbapenem-resistant Enterobacteriaceae (CRE) has been increasing in Singapore. We analyzed the clinical and molecular epidemiology of CRE among adult inpatients in Singapore. METHODS: Quarterly incidence of unique subjects (per 100000 patient-days) with positive clinical and surveillance cultures for CRE were estimated based on mandatory data submitted to the National Public Health Laboratory by public hospitals between 2010 and 2015. CRE-positive adult inpatients were prospectively recruited from 6 public sector hospitals between December 2013 and April 2015. Subjects answered a standardized epidemiologic questionnaire and provided samples for this study. Further clinical information was extracted from subjects' electronic medical records. Whole-genome sequencing was performed on study isolates to determine transmission clusters. RESULTS: Incidence of CRE clinical cultures among adult inpatients plateaued from 2013 (range: 7.73 to 10.32 per 100000 patient-days) following an initial increase between 2010 and end-2012. We prospectively recruited 249 subjects. Their median age was 65 years, 108 (43%) were female, and 161 (64.7%) had carbapenemase-producing Enterobacteriaceae (CPE). On multivariate analysis, prior carbapenem exposure (OR: 3.23; 95% CI: 1.67-6.25) and hematological malignancies (OR: 2.85; 95% CI: 1.10-7.41) were associated with non-carbapenemase-producing CRE (NCPE) (n = 88) compared with CPE (n = 161) subjects. Among 430 CRE isolates from the 249 subjects, 307(71.3%) were CPE, of which 154(50.2%) were blaKPC-positive, 97(31.6%) blaNDM-positive, and 42 (13.7%) blaOXA-positive. Klebsiella pneumoniae (n = 180, 41.9%), Escherichia coli (n = 129, 30.0%) and Enterobacter cloacae (n = 62, 14.4%) were the main Enterobacteriaceae species. WGS (n = 206) revealed diverse bacterial strain type (STs). The predominant blaKPC-positive plasmid was pHS102707 (n = 62, 55.4%) and the predominant blaNDM-positive plasmid was pNDM-ECS01 (n = 46, 48.9%). Five transmission clusters involving 13 subjects were detected. CONCLUSIONS: Clinical CRE trend among adult inpatients showed stabilization following a rapid rise since introduction in 2010 potentially due to infection prevention measures and antimicrobial stewardship. More work is needed on understanding CPE transmission dynamics.

User-Centered Design Process of an mHealth App for Health Professionals: Case Study.

BACKGROUND: User-centered design processes are infrequently employed and not fully explored for building mobile health (mHealth) apps that are particularly targeted to health professionals as end users. The authors have used a user-centered design-based approach to build an mHealth app for health professionals, tasked to deliver medical laboratory-related information on a daily basis. OBJECTIVE: Our objective is to generate a simple and functional user-centered design process for mHealth apps for health professionals. This paper presents the key learnings from design activities. METHODS: A stratified random sample of doctors and nurses was recruited for the study. The design activities were planned in the following sequence: focus group discussion for situation analysis and information architecture, design activity 1 for wireframe designing, design activity 2 for wireframe testing, and user testing sessions 1 and 2. RESULTS: The final design and functions of the app, information architecture, and interactive elements were largely influenced by the participatory design-based user-centered design activities. As a result of the design process, we could identify the mental models of processing requests for information and personal preferences based on the experience. These findings were directly or indirectly incorporated into the app design. Furthermore, finding alternative ways of working within time constraints and cultural barriers and the methods employed to manage the challenges of interdisciplinary discourse stood out among the lessons learned. CONCLUSIONS: We recommend a user-centered design process based on a participatory design approach in mHealth app design, enriched with focus group discussions where possible.

Reducing delivery times of emergency blood products through pneumatic tube systems.

OBJECTIVES: Recent advances in damage control resuscitation have advocated a push for early transfusion to maintain circulating volume and minimization of crystalloid use. While measures such as using rapid-matched group specific blood or uncrossmatched blood have been implemented to shorten this wait, delivery times can still be improved. We explored reducing delivery times by use of a pneumatic tube delivery system already built in our hospital. Few studies have evaluated this using fresh blood samples for one-way transport. We modified and evaluated our pneumatic tube delivery system for delivery timings and quality parameters; designing a robust protocol that also tested aged blood for simulated returns unlike other previous studies. METHODS: Delivery timings of emergency blood products by our present portering system were collected and compared against that of products sent through the pneumatic tube system (PTS). The samples sent through the PTS were also tested and analyzed for temperature, quality, and hemolysis in accordance with established blood banking quality guidelines. RESULTS: Blood products delivered by our PTS showed satisfactory conformance with all parameters of temperature, timing, and hemolysis. We showed a significant reduction in transport delivery times from mean of 8 min 43 s to 2 min 23 s. CONCLUSIONS: Delivery of blood products by our modified PTS is safe and significantly reduces delivery time. This time savings could be clinically significant in resuscitation. Usage of the PTS could also cut down on workforce utilization of porters, freeing them up for other tasks in the hospital.

Implementing a laboratory automation system: experience of a large clinical laboratory.

Laboratories today face increasing pressure to automate their operations as they are challenged by a continuing increase in workload, need to reduce expenditure, and difficulties in recruitment of experienced technical staff. Was the implementation of a laboratory automation system (LAS) in the Clinical Biochemistry Laboratory at Singapore General Hospital successful? There is no simple answer, so the following topics comparing and contrasting pre- and post-LAS have been explored: turnaround time (TAT), laboratory errors, and staff satisfaction. The benefits and limitations of LAS from the laboratory experience were also reviewed. The mean TAT for both stat and routine samples decreased post-LAS (30% and 13.4%, respectively). In the 90th percentile TAT chart, a 29% reduction was seen in the processing of stat samples on the LAS. However, no significant difference in the 90th percentile TAT was observed with routine samples. It was surprising to note that laboratory errors increased post-LAS. Considerable effort was needed to overcome the initial difficulties associated with adjusting to a new system, new software, and new working procedures. Although some of the known advantages and limitations of LAS have been validated, the claimed benefits such as improvements in TAT, laboratory errors, and staff morale were not evident in the initial months.

A case of green urine due to a traditional Chinese medicine containing methylene blue.

Abnormal discolouration of the urine is always alarming to the patient and intriguing to physicians. Green colouration in urine can be of endogenous or exogenous aetiology. We present a case of green urine caused by a side effect of a traditional Chinese medicine (TCM) containing methylene blue, an uncommon occurrence. This case also highlights the importance of thorough history taking from the patient, especially diet and medications. Simple analysis in the clinical biochemistry laboratory can play a role in avoiding other expensive and unnecessary investigations.