How to Close the Loop on Catheters: Exploring limitations and opportunities at the end-of-life of single-use catheters

While lives are saved through the use of medical devices; they have a significant negative impact on the environment. In particular single-use medical devices make up a large part of the healthcare sector’s negative environmental impact as they contribute significantly to generating more medical waste and greenhouse gas emissions. Approximately 90% of medical waste consists of single-use products or components. The incineration of medical waste is still common practice, leading to harmful environmental and human health effects. Additionally, devices that could potentially be recycled, reused, or repurposed in another way to help close the loop of a product’s life cycle are incinerated instead, which sustains and fuels the unsustainable linear economic model. This research aims to identify opportunities at the end-of-life of single-use catheters that could sustain value and limit the amounts of medical waste produced. A method is presented that supports approaching this aim, called the recovery assessment tool for single-use catheters. The presented method allows for identifying components of a catheter that limit or provide opportunities for recovery purposes at the end-of-life. Two protocols have been developed to guide this process. The first protocol covers the dismantling process to explore the build-up of a catheter and separate components to establish a Bill of Materials. The second protocol describes the procedure that was followed to analyse a catheter. The Bill of Materials is used as an input to assess a catheter at the sub-assembly and component level. The assessment evaluates a catheter on three types of indices: disassembly indices, hygienic recovery indices and material recovery indices. The outcome of the assessment is a graphical visualization that highlights areas of attention for recovery. By interpreting these results using the explanations given with each index, components can be identified that limit or provide opportunities for recovery purposes at the end-of-life of single-use catheters. Two single-use catheters of Philips were assessed as a case study with the proposed methodology. A Bill of Materials for each catheter was established with the results of a material investigation in the lab. The results of the case studies led to several limitations and opportunities. The first limitation is that cleaning catheters can be challenging, given their long tubular shape and the fact that almost all components and sub-assemblies cannot be disassembled and reassembled again. This limitation may impede recovery options since catheters must be cleaned and sterilised after use if considered for recovery purposes because they come into contact with blood. Additionally, catheters are lightweight devices, meaning they make up only a small amount of the piles of medical waste produced daily. Still, catheters are high-value devices; therefore, any form of recovery is valuable. Opportunities for recovery at the end-of-life of catheters have also been identified. It was determined that catheters contain valuable metals that could be recovered to reduce medical waste, sustain value and potentially decrease the demand to collect raw materials. Also, most of the materials used in the case studied catheters seem compatible with ethylene oxide sterilisation which provides an opportunity for recovery; however, this must be thoroughly validated. Finally, it is suggested to reconsider the design or build-up of a catheter. Investigating opportunities for a hybrid design and exploring the possibility of recovery of functional modules for new catheters at the end-of-life are suggested. The outcomes of this research indicate that closing the loop on single-use catheters is a complex problem in terms of circularity due to their hygienic criticality and light weight compared to the waste produced daily per hospital bed. The amount of medical waste produced due to the use of catheters is only the tip of the iceberg.Biomedical Engineerin

Outcomes after Surgical Treatment for Rectal Atresia in Children: Is There a Preferred Approach? A Systematic Review

Rectal atresia (RA) affects only 1 to 2% of all children with anorectal malformations. No consensus on optimal treatment strategy is yet achieved. Therefore, the aim of this systematic review is to summarize all surgical interventions for RA and outcomes described in the current literature. A literature search was conducted in PubMed, Embase, Web of Science, and Cochrane Library on January 24, 2022. All studies describing treatment for RA in children (< 18 years) were included. Operation technique and postoperative complications were listed. Only descriptive analysis was anticipated. Quality of the studies was assessed using Johanna Briggs Institute critical appraisal checklist for case reports and series. The search yielded 6,716 studies of which, after duplicate removal, 4,028 were excluded based on title and abstract screening. After full-text assessment, 22 of 90 studies were included, yielding 70 patients. Posterior sagittal anorectoplasty (PSARP) and pull-through were most performed (43/70 and 18/70 patients, respectively). Four patients experienced postoperative complications: anal stenosis (n = 1), anastomotic stenosis (n = 2), and death due to a pulmonary complication (n = 1). In the low-quality literature available, most patients with RA are treated with PSARP or pull-through technique. A low complication rate of both has been described but follow-up was often not mentioned. Larger well-designed studies should be performed to determine optimal treatment strategy for children with RA. This study reflects level of evidence V

Fourth mRNA COVID-19 vaccination in immunocompromised patients with haematological malignancies (COBRA KAI): a cohort study.

Background: Patients with haematological malignancies have impaired antibody responses to SARS-CoV-2 vaccination. We aimed to investigate whether a fourth mRNA COVID-19 vaccination improved antibody quantity and quality. Methods: In this cohort study, conducted at 5 sites in the Netherlands, we compared antibody concentrations 28 days after 4 mRNA vaccinations (3-dose primary series plus 1 booster vaccination) in SARS-CoV-2 naive, immunocompromised patients with haematological malignancies to those obtained by age-matched, healthy individuals who had received the standard primary 2-dose mRNA vaccination schedule followed by a first booster mRNA vaccination. Prior to and 4 weeks after each vaccination, peripheral blood samples and data on demographic parameters and medical history were collected. Concentrations of antibodies that bind spike 1 (S1) and nucleocapsid (N) protein of SARS-CoV-2 were quantified in binding antibody units (BAU) per mL according to the WHO International Standard for COVID-19 serological tests. Seroconversion was defined as an S1 IgG concentration &gt;10 BAU/mL and a previous SARS-CoV-2 infection as N IgG &gt;14.3 BAU/mL. Antibody neutralising activity was tested using lentiviral-based pseudoviruses expressing spike protein of SARS-CoV-2 wild-type (D614G), Omicron BA.1, and Omicron BA.4/5 variants. This study is registered with EudraCT, number 2021-001072-41. Findings: Between March 24, 2021 and May 4, 2021, 723 patients with haematological diseases were enrolled, of which 414 fulfilled the inclusion criteria for the current analysis. Although S1 IgG concentrations in patients significantly improved after the fourth dose, they remained significantly lower compared to those obtained by 58 age-matched healthy individuals after their first booster (third) vaccination. The rise in neutralising antibody concentration was most prominent in patients with a recovering B cell compartment, although potent responses were also observed in patients with persistent immunodeficiencies. 19% of patients never seroconverted, despite 4 vaccinations. Patients who received their first 2 vaccinations when they were B cell depleted and the third and fourth vaccination during B cell recovery demonstrated similar antibody induction dynamics as patients with normal B cell numbers during the first 2 vaccinations. However, the neutralising capacity of these antibodies was significantly better than that of patients with normal B cell numbers after two vaccinations. Interpretation: A fourth mRNA COVID-19 vaccination improved S1 IgG concentrations in the majority of patients with a haematological malignancy. Vaccination during B cell depletion may pave the way for better quality of antibody responses after B cell reconstitution. Funding: The Netherlands Organisation for Health Research and Development and Amsterdam UMC.</p

Fourth mRNA COVID-19 vaccination in immunocompromised patients with haematological malignancies (COBRA KAI): a cohort studyResearch in context

Summary: Background: Patients with haematological malignancies have impaired antibody responses to SARS-CoV-2 vaccination. We aimed to investigate whether a fourth mRNA COVID-19 vaccination improved antibody quantity and quality. Methods: In this cohort study, conducted at 5 sites in the Netherlands, we compared antibody concentrations 28 days after 4 mRNA vaccinations (3-dose primary series plus 1 booster vaccination) in SARS-CoV-2 naive, immunocompromised patients with haematological malignancies to those obtained by age-matched, healthy individuals who had received the standard primary 2-dose mRNA vaccination schedule followed by a first booster mRNA vaccination. Prior to and 4 weeks after each vaccination, peripheral blood samples and data on demographic parameters and medical history were collected. Concentrations of antibodies that bind spike 1 (S1) and nucleocapsid (N) protein of SARS-CoV-2 were quantified in binding antibody units (BAU) per mL according to the WHO International Standard for COVID-19 serological tests. Seroconversion was defined as an S1 IgG concentration >10 BAU/mL and a previous SARS-CoV-2 infection as N IgG >14.3 BAU/mL. Antibody neutralising activity was tested using lentiviral-based pseudoviruses expressing spike protein of SARS-CoV-2 wild-type (D614G), Omicron BA.1, and Omicron BA.4/5 variants. This study is registered with EudraCT, number 2021-001072-41. Findings: Between March 24, 2021 and May 4, 2021, 723 patients with haematological diseases were enrolled, of which 414 fulfilled the inclusion criteria for the current analysis. Although S1 IgG concentrations in patients significantly improved after the fourth dose, they remained significantly lower compared to those obtained by 58 age-matched healthy individuals after their first booster (third) vaccination. The rise in neutralising antibody concentration was most prominent in patients with a recovering B cell compartment, although potent responses were also observed in patients with persistent immunodeficiencies. 19% of patients never seroconverted, despite 4 vaccinations. Patients who received their first 2 vaccinations when they were B cell depleted and the third and fourth vaccination during B cell recovery demonstrated similar antibody induction dynamics as patients with normal B cell numbers during the first 2 vaccinations. However, the neutralising capacity of these antibodies was significantly better than that of patients with normal B cell numbers after two vaccinations. Interpretation: A fourth mRNA COVID-19 vaccination improved S1 IgG concentrations in the majority of patients with a haematological malignancy. Vaccination during B cell depletion may pave the way for better quality of antibody responses after B cell reconstitution. Funding: The Netherlands Organisation for Health Research and Development and Amsterdam UMC