P3599Minicare high sensitivity troponin: a novel point-of-care tool to improve ACS workflows

Background

Cardiac troponin (cTn) has been broadly accepted as the biomarker of choice in the diagnosis of patients presenting with Acute Coronary Syndrome (ACS). Point-of-care (POC) cTn testing, defined as testing near the patient with rapid availability of results, has attracted a strong interest in the emergency department (ED) setting. It offers the potential to improve workflows, expedite clinical decisions and to reduce the length of stay. Workflows could be further optimized when a first measurement can already be performed by the emergency medical services prior to admission to the hospital.

Advances in assay technology have led to high sensitive (HS) cTn assays that have a profound impact on clinical practice, providing early results at presentation and 1 hour after admission which speed up clinical decision-making. Here we evaluate the Minicare HS cTnI POC test under development, which has the potential to combine the benefits of HS-cTnI protocols with a POC workflow.

Objective

Evaluate the analytical and clinical capability of the Minicare HS-cTnI test under development to meet the criteria‡ for HS cTn of having a 10% CV <99th percentile and a percentage measurable (>LoD) of >50%.

Methods

The evaluation is based on the Clinical Laboratory Standards Institute (CLSI) guidelines. Li-heparin whole blood and Li-heparin plasma samples were used to establish LoB, LoD, and LoQ, sample matrix comparison and linearity in the low range. The clinical performance for Minicare HS-cTnI was assessed and compared to Abbott Architect high-sensitivity troponin using banked samples from patients with ACS and collected at t=2–4h after admission. The percentage measurable was assessed and compared to Abbott Architect high-sensitivity troponin in a healthy population of 165 individuals.

Results

With a time to result within 10 minutes, the LoB is determined at 1.0 ng/L and the LoD at 2.1 ng/L. Plasma and whole blood results correlated well and showed comparable results. The 10% and 20% CV LoQ are established at 7.9 ng/L and 3.1 ng/L, well below the anticipated 99th percentile of 26 ng/L. With a percentage measurable of 77%, the criteria for a HS-cTnI assay are met in a POC device. A sensitivity of 93% and an NPV of 99% are found for Minicare HS-cTnI for a t=2–4h protocol vs 90% and 98% for Abbott Architect high-sensitivity troponin. In this study the area under the curve is 0.98 for Minicare HS-cTnI and 0.97 for Architect HS-cTnI.

ROC curve t=2-4 h

Conclusions

With HS-cTnI capability on the Minicare platform, we show the potential to support a 0/1 h sampling protocol, combined with the speed of a POC workflow. This may enable even more rapid and safe rule-out of patients with ACS.

Home initiation of chronic non-invasive ventilation in COPD patients with chronic hypercapnic respiratory failure: a randomised controlled trial

INTRODUCTION

Chronic non-invasive ventilation (NIV) has become evidence-based care for stable hypercapnic COPD patients. While the number of patients increases, home initiation of NIV would greatly alleviate the healthcare burden. We hypothesise that home initiation of NIV with the use of telemedicine in stable hypercapnic COPD is non-inferior to in-hospital NIV initiation.

METHODS

Sixty-seven stable hypercapnic COPD patients were randomised to initiation of NIV in the hospital or at home using telemedicine. Primary outcome was daytime arterial carbon dioxide pressure (PaCO₂) reduction after 6 months NIV, with a non-inferiority margin of 0.4 kPa. Secondary outcomes were health-related quality of life (HRQoL) and costs.

RESULTS

Home NIV initiation was non-inferior to in-hospital initiation (adjusted mean difference in PaCO₂ change home vs in-hospital: 0.04 kPa (95% CI -0.31 to 0.38 kPa), with both groups showing a PaCO₂ reduction at 6 months compared with baseline (home: from 7.3±0.9 to 6.4±0.8 kPa (p<0.001) and in-hospital: from 7.4±1.0 to 6.4±0.6 kPa (p<0.001)). In both groups, HRQoL improved without a difference in change between groups (Clinical COPD Questionnaire total score-adjusted mean difference 0.0 (95% CI -0.4 to 0.5)). Furthermore, home NIV initiation was significantly cheaper (home: median €3768 (IQR €3546-€4163) vs in-hospital: median €8537 (IQR €7540-€9175); p<0.001).

DISCUSSION

This is the first study showing that home initiation of chronic NIV in stable hypercapnic COPD patients, with the use of telemedicine, is non-inferior to in-hospital initiation, safe and reduces costs by over 50%.

TRIAL REGISTRATION NUMBER

NCT02652559.

[Diaphragm pacemaker: alternative for long-term ventilatory support; 5 years later]

Currently, more than 3000 patients in the Netherlands receive long-term ventilatory support. In the majority of patients, long-term ventilatory support leads to increased survival without any complications. Diaphragm pacing with an external pacemaker (diaphragm pacing system, DPS) seems an attractive alternative for long-term ventilatory support by mask or tracheostomy. Scientific research has since shown that DPS is effective in patients with high cervical paraplegia. In addition, patients with congenital central hypoventilation syndrome are also eligible for DPS. Patients with diaphragm paralysis are a new group of patients who may be eligible for DPS. Two European studies have shown that DPS should not be used in patients with amyotrophic lateral sclerosis. In our experience, patients are no longer completely dependent on a ventilator or may even be able to discontinue using one if the procedure was successful. In the Netherlands, as far as we know, the technique is only used at the University Medical Center Groningen.

Synthesis of polylactides, polyglycolides and their copolymers

An overview is given of several polymerization routes of lactides and glycolides. Well-known in the literature are melt- and bulk-polymerization. These two polymerization types are discussed, showing that they have certain advantages and disadvantages. Less known are the solution and suspension polymerization of lactides and glycolides. These two techniques are described in detail. In certain cases these polymerizations have advantages over the aforementioned ones. It is shown that lower system viscosity enables better heat transfer during the reaction, resulting in a better, controllable reaction. The first results of solution and suspension polymerization are presented, showing that these techniques have great potential in the future.

Fever and changes in plasma zinc and iron concentrations in the goat: the role of leukocytic pyrogen

In goats with trypanosomiasis (T. vivax or T. congolense) no marked fall in plasma zinc concentration was seen despite high temperature peaks, whereas plasma concentrations of iron tended to undergo some decline. In goats infected with Ehrlichia phagocytophila, there was a marked decline in plasma zinc and iron to low values on the 3rd and 4th day, respectively. Circulating endogenous pyrogen (EP) or leukocytic endogenous mediator (LEM) could not be detected in plasma from febrile goats with tick-borne fever. The intravenous injection of leukocytic pyrogen (LP) in kids caused characteristic monophasic febrile reactions, whereas no significant changes in plasma trace metals were found. So, previous evidence purporting to show that LP is similar to or may be identical with LEM is demonstrably inconclusive. Intravenous injection of E. coli lipopolysaccharide (LPS) or staphylococcal enterotoxin B (SEB) induced fever and lowering of plasma zinc and iron concentrations. The decrease in those trace metal values was more persistent in goats given SEB than in those given E. coli LPS. After intramammary infusion of SEB or E. coli LPS, fever and significant decreases in plasma zinc and iron concentrations were observed but no clear relationship was found between the temperature responses and the alterations in plasma trace metal concentrations. Furthermore, the decrease in plasma iron concentration developed more rapidly in goats given SEB than in those given E. coli LPS, whereas the decrease in plasma zinc concentrations in the former was more delayed. These data support the theory that the concentrations of zinc and iron in plasma are regulated by different mechanisms, whereas febrile reactions are mediated by another type of endogenous protein.