Quality Improvement at the Laboratory’s Specimen Reception Station

Introduction/Objective

In our 1000-bed acute care tertiary hospital, physicians order laboratory tests via the computerized-provider-order-entry (CPOE) system and print barcode labels (patient demographics/tests ordered) at the computer-on-wheel printer. When tubes with unsuitable barcodes (misaligned, poor quality) are received at the laboratory specimen reception area a fresh barcode is re-printed by our laboratory staff. An incident involving a re- printed barcode label pasted on the wrong blood tube prompted an investigation into the quality of barcodes.

Methods/Case Report

We initiated ‘an opportunity for improvement (OFI) project’ at the laboratory specimen reception station. The OFI team involved Nursing, Information Technology (IT) and Pathology departments aimed to eliminate re-printing of barcode labels by 75% within 6 months. We collated and analyzed reasons for re-printing of barcodes on 3 separate 48-hour periods (27-28 April 2020, 24-25 June 2020, and 13-14 June 2022). A series of interventions and initiatives were implemented.

Results (if a Case Study enter NA)

Re-printed barcodes were from the Emergency Department (56%), Out-patient clinics (7%) and Wards (57%). Root cause analysis(RCA) using the “5 whys” technique categorized re-print causes into staff-related (misaligned barcodes) and printer-related (faint barcodes lines/truncated un-verifiable patient demographics). The team mass-emailed clinicians an educational “Do-You-Know” guide on proper pasting of barcodes on blood tubes and instructions on how to obtain help for printer rectification. These guide documents were placed in the hospital-wide document-sharing portal - Docupedia. Immediate close follow-up with sites that had poor barcodes was done in real-time. Barcode reprints decreased 83% within 2 months - from 174 (27-28 Apr 2020) to 30 (24-25 Jun 2020). A recent audit showed sustained elimination of barcode re-printing: 25 cases (13-14 Jun 2022).

Conclusion

The OFI project has successfully raised the quality of CPOE labels on specimen tubes contributing to process efficiency and safer patient care. Close communication with all care sites and their representatives on the OFI team are critical success factors.

Single-Atom Electrocatalysis for Hydrogen Evolution Based on the Constant Charge and Constant Potential Models

DFT calculations are performed at constant charge, while practical electrochemical reactions often take place under constant potential. To unravel the effect of the model difference on single-atom electrocatalysis, we implement benchmarked DFT and grand-canonical DFT calculations to systematically investigate the hydrogen adsorption on 99 single-atom M-N_xC_y motifs. We find that the initial electrode potentials for all M-N_xC_y are negative, leading to the loss of system electrons once their electrode potentials are fixed at 0 V/SHE. We prove that the quantitive difference of ΔG(*H) between the CCM and CPM is proportional to the square difference of total charge change before and after H adsorption, which originates from the adjustment of electronic occupation states. Our work provides theoretical insight into the differential capacitance model in the graphene-confining SACs for the HER and emphasizes the importance of CPM for in silico design of electrocatalysts.

Thermal drift correction method for laboratory nanocomputed tomography based on global mixed evaluation

Nanocomputed tomography (nanoCT) is an effective tool for the nondestructive observation of 3D structures of nanomaterials; however, it requires additional correction phantom to reduce artifacts induced by the focal drift of the X-ray source and mechanical thermal expansion. Drift correction without a correction phantom typically uses rapidly acquired sparse projections to align the original projections. The noise and brightness difference in the projections limit the accuracy of existing feature-based methods such as locality preserving matching (LPM) and random sample consensus (RANSAC). Herein, a rough-to-refined correction framework based on global mixed evaluation (GME) is proposed for precise drift estimation. First, a new evaluation criterion for projection alignment, named GME, which comprises the structural similarity (SSIM) index and average phase difference (APD), is designed. Subsequently, an accurate projection alignment is achieved to estimate the drift by optimizing the GME within the proposed correction framework based on the rough-to-refined outlier elimination strategy. The simulated 2D projection alignment experiments show that the accuracy of the GME is improved by 14× and 12× than that of the mainstream feature-based methods LPM and RANSAC, respectively. The proposed method is validated through actual 3D imaging experiments.

Assessment of optimal thresholds for ventricular scar substrate characterization using the high density grid multipolar mapping catheter

Funding Acknowledgements

Type of funding sources: None.

Background

Voltage thresholds for ventricular scar definition are based on historic data collected using catheters with widely spaced bipoles in the absence of contact force. Modern multipolar mapping catheters employ smaller electrodes and interelectrode spacing that theoretically allows for mapping with increased resolution and reduced far-field electrogram (EGM) component. Despite the advancement in technology, historic cut-offs of <0.5mV for dense scar and 0.5-1.5mV for scar borderzone continue to be used in contemporary electrophysiology.

Purpose

We aimed to assess the optimal voltage cut-offs for ventricular scar substrate characterization using the HD Grid multipolar mapping catheter. Voltage cut-offs were assessed against cardiac MRI derived scar. We compared optimal voltage cut-offs using conventional bipolar sampling, the Best Duplicate Algorithm and with the HD wave solution plus best duplicate algorithm on.

Methods

A multicentre study of twenty patients undergoing VT ablation was conducted. Substrate mapping was performed using the high-density HD-grid multipolar mapping catheter. Bipolar voltage maps were co-registered with cardiac MRI obtained prior to the procedure to assess the voltage characteristics of scar defined by cardiac MRI (CMR) (Figure 1). Pre-procedure contrast enhanced CMR data were analysed using ADAS software (Galgo medical). Data points were collected in regions of scar during (1) HD wave mapping with best duplicate algorithm on(Waveon), (2) Mapping with HD wave off and best duplicate on (Waveoff) and (3) with conventional bipolar mapping (Alloff).

Results

The median bipolar voltage for regions of dense CMR scar using (Waveon) HD wave solution and best duplicate algorithm was 0.27mV (IQR 0.14 – 0.46). The median voltage with (Waveoff) HD wave off was 0.29mV (0.15 – 0.45). The median voltage with (Alloff) HD wave off and best duplicate off was 0.32mV (0.19 – 0.5). ROC analysis using AUC suggested the optimal cut-off for endocardial dense scar using (Waveon) HD wave mapping and best duplicate algorithm was 0.30mV (sensitivity: 69.6%, specificity: 60.74%), (Waveoff) cut-off with the best duplicate and without the HD wave mapping was 0.34mV (sensitivity: 69.78%, specificity: 64.46%) and (Alloff) without wave mapping or best duplication was 0.36mV (sensitivity: 84%, specificity: 52%) Figure 2.

Conclusion

Ventricular substrate characterization with newer mapping technology using narrow electrode spacing and smaller electrode size suggests that traditional voltage cut-offs may need revision for delineation of scar characteristics. Additionally, the ability to repeat sample in a region to obtain the best signal (Best Duplicate), and the ability to obviate the effect of wavefront direction using the HD wave solution omnipolar technology, may further increase the fidelity of scar characterization. This has important implications for mapping VT and characterizing channels in order to identify VT circuits.

Integration of structural and functional data in VT ablation -- SENSE2 protocol mapping

Funding Acknowledgements

Type of funding sources: None.

Background

We have previously developed the sense protocol functional substrate mapping technique for VT ablation(1). However, functional substrate characterizaiton can involve protracted mapping time.

Purpose

We incorporated the integration of MRI data using ADAS-3D software into the mapping workflow, to integrate structural mapping information into the functional mapping substrate characterization, in order to improve procedural efficiency.

Methods

CMRs were performed in 20 patients with ischemic related VT and VT therapy in the previous 6 months. These were processed with the ADAS-3D software to characterize the extent of ventricular scars and also ADAS corridors which may correlate with VT channels. Focused substrate maps were then performed in patients, guided by the extent of ADAS scar and corridors, looking at the scar substrate in intrinsic rhythm and then functional channels using single extra pacing from the RV at 20ms above ERP (SENSE2 Protocol). Specifically healthy areas 2cm beyond the scar borderzone based on ADAS were not mapped, in order to reduce substrate mapping time and complete geometries were not created. Following delineation of functional channels pacemapping and entrainment mapping were used to confirm targets for ablation.

The ADAS 3D MRI was integrated into the into the VT substrate map on Ensite-Precision with alignment to the aorta, RV and PA (Figure 1). We compared our data with previous functional mapping data without the integration of MRI.

Results

20 patients (age 70 years; 19 male subjects) underwent ablation. Mean EF 28%. Median procedure time was 161 minutes compared with 246 minutes (in our previous study)(p=<0.001) Mean substrate mapping time was 32 mins vs 63 mins (p=<0.001). Mean ablation time was 22 mins vs 32 mins (p=0.11). 85% (17 of 20) patients were free from symptomatic VT/ anti-tachycardia pacing or implantable cardioverter defibrillator shocks at a median follow-up of 171 days. The mean VT burden was reduced from 22 events per patient in the 6 months’ pre-ablation to 1 event per patient in the median follow up period of 171 days post ablation (p=0.02). Mean shocks per-patient burden decreased from 3.5 to 0.08 in the same time period(p=0.03).

Conclusion

The SENSE2 protocol involves the integration of structural and functional data into the VT workflow for substrate characterization. It enables focused substrate maps to be performed without the need for complete geometry to be created in large ventricles. Outcomes compare favourably with our previous data but with significantly shorter procedure times. This streamlined workflow has the potential to improve care in VT ablation by shortening procedure times with similar outcomes which may reduce risks for the patient.

Figure 1: Comparison of Voltage Map with MRI scar & corridors using ADAS

Spatial distribution and functional analysis define the action pathway of Tim-3/Tim-3 ligands in tumor development

The spatial organization of immune cells within the tumor microenvironment (TME) largely determines the anti-tumor immunity and also highly predicts tumor progression and therapeutic response. Tim-3 is a well-accepted immune checkpoint and plays multifaceted immunoregulatory roles via interaction with distinct Tim-3 ligands (Tim-3L), showing great potential as an immunotherapy target. However, the cell sociology mediated by Tim-3/Tim-3L and their contribution to tumor development remains elusive. Here, we analyzed the spatial distribution of Tim-3/Tim-3L in TME using multiplex fluorescence staining and revealed that despite the increased Tim-3 expression in various tumor-infiltrated lymphocytes, Tim-3⁺CD4⁺ cells were more accumulated in parenchymal/tumor region compared with stromal region and exhibited more close association with patient survival. Strikingly, CD4 T cells surrounding Tim-3L⁺ cells expressed higher Tim-3 than other cells in cancerous tissues. In vivo studies confirmed that depletion of CD4 T cells completely abrogated the inhibition of tumor growth and metastasis, as well as the functional improvement of CD8 T and NK, mediated by Tim-3 blockade, which was further validated in peripheral lymphocytes from patients with hepatocellular carcinoma. In conclusion, our findings unravel the importance of CD4 T cells in Tim-3/Tim-3L-mediated immunosuppression and provide new thoughts for Tim-3 targeted cancer immunotherapy.

Photophosphatidylserine Guides Natural Killer Cell Photoimmunotherapy via Tim-3

Natural killer (NK) cells, in addition to their cytotoxicity function, harbor prominent cytokine production capabilities and contribute to regulating autoimmune responses. T-cell immunoglobulin and mucin domain containing protein-3 (Tim-3) is one of the inhibitory receptors on NK cells and a promising immune checkpoint target. We recently found that phosphatidylserine (PS) binding to Tim-3 can suppress NK cell activation. Therefore, based on the therapeutic potential of Tim-3 in NK-cell-mediated diseases, we developed a photoswitchable ligand of Tim-3, termed photophosphatidylserine (phoPS), that mimics the effects of PS. Upon 365 or 455 nm light irradiation, the isomer of phoPS cyclically conversed the cis/trans configuration, resulting in an active/inactive Tim-3 ligand, thus modulating the function of NK cells in vitro and in vivo. We also demonstrated that reversible phoPS enabled optical control of acute hepatitis. Together, phoPS may be an appealing tool for autoimmune diseases and cytokine storms in the future.

CD169-positive macrophages enhance abscopal effect of radiofrequency ablation therapy in liver cancer

Radiofrequency ablation (RFA) is a widely used and effective treatment for primary or metastatic liver cancer with small-size lesions. However, the therapeutic effectiveness of RFA in controlling metastatic lesion or recurrence is still limited. As the major cell population in tumor microenvironment (TME), macrophages have been reported to be recruited to RFA-treated lesion, but their roles are still unclear. Herein, we successfully established the mouse model mimicking RFA-induced abscopal effect, in which RFA eliminated the local orthotopic liver tumor but failed to control growth of distant tumor. Correspondently, RFA suppressed protumoral activation of local tumor-associated macrophages (TAMs), but failed to reprogram TAMs in distance. Importantly, although RFA led to reduced proportion of hepatic CD169⁺ macrophages in local and decreased expression of immune inhibitory molecules Tim-3 and PD-L1, these alterations were not observed for CD169⁺ macrophages in distant TME. Further RNA-seq and flow cytometry analysis showed that hepatic CD169⁺ macrophages contributed to reprograming TME through recruiting CD8⁺ T/NK cells and suppressing accumulation of MDSCs/Tregs. Consistently, depletion of CD169⁺ macrophages in CD169-DTR mouse greatly promoted liver tumor progression and largely dampened RFA-induced tumor suppression. Notably, transfer of CD169⁺ macrophages synergistically enhanced RFA-induced inhibition of distant tumor. To our knowledge, this is the first study which demonstrates hepatic CD169⁺ macrophages as a key factor responsible for RFA-induced abscopal effect. Our data suggest RFA with transfer of CD169⁺ macrophages as a promising combination therapy to lessen metastasis or recurrence of liver cancer in patients.

Full-coverage spatiotemporal mapping of ambient PM2.5 and PM10 over China from Sentinel-5P and assimilated datasets: Considering the precursors and chemical compositions

Ambient concentrations of particulate matters (PM_2.5 and PM₁₀) are significant indicators for monitoring the air quality relevant to living conditions. At present, most remote sensing based approaches for the estimation of PM_2.5 and PM₁₀ employed Aerosol Optical Depth (AOD) products as the main variate. Nevertheless, the coverage of missing data is generally large in AOD products, which can cause deviations in practical applications of estimated PM_2.5 and PM₁₀ (e.g., air quality monitoring and exposure evaluation). To efficiently address this issue, our study explores a novel approach using the datasets of the precursors & chemical compositions for PM_2.5 and PM₁₀ instead of AOD products. Specifically, the daily full-coverage ambient concentrations of PM_2.5 and PM₁₀ are estimated at 5-km (0.05°) spatial girds across China based on Sentinel-5P and assimilated datasets (GEOS-FP). The estimation models are acquired via an advanced ensemble learning method named Light Gradient Boosting Machine in this paper. For comparison, the Deep Blue AOD product from VIIRS is adopted in a similar framework as a baseline (AOD-based). Validation results show that the ambient concentrations are well estimated through the proposed approach, with the space-based Cross-Validation R²s and RMSEs of 0.88 (0.83) and 11.549 (22.9) μg/m³ for PM_2.5 (PM₁₀), respectively. Meanwhile, the proposed approach achieves better performance than the AOD-based in different cases (e.g., overall and seasonal). Compared to the related previous works over China, the estimation accuracy of our method is also satisfactory. Regarding the mapping, the estimated results through the proposed approach display consecutive spatial distribution and can exactly express the seasonal variations of PM_2.5 and PM₁₀. The proposed approach could efficiently present daily full-coverage results at 5-km spatial grids. It has a large potential to be extended for providing global accurate ambient concentrations of PM_2.5 and PM₁₀ at multiple temporal scales (e.g., daily and annual).

Pigment concentrations in eggshell and their related gene expressions in uterus of Changshun blue eggshell chickens

1. The goal of this study was to investigate the colour diversity of egg shells and expression of related genes in the uterus of chickens that produce eggs of different colours.2. Four colour types of Changshun blue-shell chickens, producing dark or light blue, greenish-brown and brown shelled eggs, were selected. The eggshell pigment concentration and colour values in each group were examined. The relative gene expression of solute carrier organic anion transporter family member 1C1 (SLCO1C1), ferrochelatase (FECH), haem oxygenase 1 (HO-1), ovotransferrin (OF) and biliverdin reductase A (BLVRA) in eggshell gland were measured.3. The Δb, ΔE and protoporphyrin in brown and greenish-brown groups were significantly higher in the blue egg group (P < 0.01), whereas ΔL was significantly lower than that in the blue eggs (P < 0.01). There was no significant difference in biliverdin concentration between the brown and blue groups.4. The Δa values, in descending order, were 8.27 ± 2.76 in the brown, -3.79 ± 2.39 in the greenish-brown and -7.29 ± 2.27 in the blue groups, respectively. The relative expression of HO-1 in the greenish-brown and light blue groups was significantly higher than in the dark blue and brown groups. The relative expression of FECH in the light blue group was significantly lower than that in the dark blue, greenish-brown or brown group (P < 0.01). The relative expression of HO-1 and BLVRA genes in the dark blue group was significantly higher than that in the light blue, greenish-brown and the brown group (P < 0.01).5. The Δa might provide a better index than protoporphyrin and biliverdin contents for eggshell colour breeding. Overall, HO-1 as well as BLVRA were important candidate genes for the selection of dark blue eggs.

Long term prognostic utility of exercise capacity in renal transplant candidates

Background

Pharmacological stress testing is commonly performed for cardiovascular risk stratification in potential renal transplant candidates due to a perceived inability for these patients to exercise. We have previously reported that exercise stress testing is feasible in renal transplant candidates but the prognostic utility of exercise capacity in this patient group is not known.

Purpose

This study prospectively evaluated the effect of exercise capacity on the risk of major adverse cardiovascular events (MACE), defined as a composite of cardiac death, non-fatal myocardial infarction, and stroke, in renal transplant candidates undergoing exercise stress echocardiography (ESE) for pre-transplant cardiovascular assessment.

Methods

We evaluated 898 consecutive patients with chronic kidney disease stage 4/5 who underwent symptom-limited treadmill ESE over 5-year mean follow-up. Exercise capacity was measured by age and sex predicted metabolic equivalents (METs). The primary outcome was achievement of predicted METs with first MACE. Cox proportional hazard multivariable modelling was used to determine MACE predictors with transplantation treated as a time-varying covariate. We also performed secondary analysis using a 7 MET threshold.

Results

There were 106 MACE with an annual cumulative risk of 2.4%. During follow-up, 525 (58%) received transplantation. Achievement of predicted METs (48%) (hazard ratio (HR) 0.49, 95% confidence interval (CI) 0.29–0.82, p=0.007) and transplantation (HR 0.52, 95% CI 0.30–0.91, p=0.02) were independently associated with reduced MACE. Similar results were observed using a 7 MET threshold achieved by 734 (82%) patients. Patients achieving predicted METs had no difference in MACE regardless of subsequent transplantation (HR 0.78, 95% CI 0.32–1.92, p=0.59). Patients who achieved predicted METs and did not receive transplantation had similar outcomes to those that did not achieve predicted METs and received transplantation (HR 0.97, 95% CI 0.42–2.25, p=0.95).

Conclusions

Exercise capacity is associated with reduced long-term MACE in renal transplant candidates undergoing ESE for pre-transplant cardiovascular assessment. Achievement of age and sex predicted METs confers excellent prognosis independent of subsequent transplantation.

Funding Acknowledgement

Type of funding sources: None.

Assessing learner engagement with virtual educational events: Development of the Virtual In-Class Engagement Measure (VIEM)

BACKGROUND

The COVID-19 pandemic has necessitated virtual education, but effects on learner engagement are unknown. We developed a virtual in-class engagement measure (VIEM) to assess learner engagement in online surgical education events.

METHODS

Using the STROBE, an observer collected tool to document student engagement, as a template an ASE committee workgroup developed the VIEM. The VIEM had two parts: observer assessment and learner self-assessment of engagement. Trained observers collected engagement data from two institutions using the VIEM. Surgical attendings, fellows and residents were observed during virtual learning events. Educator attitudes towards online teaching were also assessed via survey.

RESULTS

22 events with 839 learners were observed. VIEM distinguished between sessions with low and high engagement. 20% of learners pretended to participate. Half of instructors were comfortable with virtual teaching, but only 1/3 believed was as effective as in-person. 2/3 of teachers believed video learners were more engaged than audio learners.

CONCLUSIONS

Virtual platforms do not automatically translate into increased engagement. Standard tools such as VIEM may help with assessment of engagement during virtual education.

Transcription factor Zhx2 restricts NK cell maturation and suppresses their antitumor immunity

The maturation and functional competence of natural killer (NK) cells is a tightly controlled process that relies on transcription factors (TFs). Here, we identify transcriptional repressor zinc fingers and homeoboxes 2 (Zhx2) as a novel regulator that restricts NK cell maturation and function. Mice with Zhx2 conditional deletion in NK cells (Zhx2Δ/Δ) showed accumulation of matured NK cells. Loss of Zhx2 enhanced NK cell survival and NK cell response to IL-15. Transcriptomic analysis revealed Zeb2, a key TF in NK cell terminal maturation, as a direct downstream target of Zhx2. Therapeutically, transfer of Zhx2-deficient NK cells resulted in inhibition of tumor growth and metastasis in different murine models. Our findings collectively unmask a previously unrecognized role of Zhx2 as a novel negative regulator in NK cell maturation and highlight its therapeutic potential as a promising strategy to enhance NK cell-mediated tumor surveillance.