Performance of closed-loop systems for intravenous drug administration: a systematic review and meta-analysis of randomised controlled trials

Closed-loop drug delivery systems are autonomous computers able to administer medication in response to changes in physiological parameters (controlled variables). While limited evidence suggested that closed-loop systems can perform better than manual drug administration in certain settings, this technology remains a research tool with an uncertain risk/benefit profile. Our aim was comparing the performance of closed-loop systems with manual intravenous drug administration in adults. We searched MEDLINE, CENTRAL, and Embase from inception until November 2022, without restriction to language. We assessed for inclusion randomised controlled trials comparing closed-loop and manual administration of intravenous drugs in adults, intraoperatively or in the Intensive Care Unit. We identified 32 studies on closed-loop administration of propofol, noradrenaline, phenylephrine, insulin, neuromuscular blockers, and vasodilators. Most studies were at moderate or high risk of bias. The results showed that closed-loop systems reduced the duration of blood pressure outside prespecified targets during noradrenaline (MD 14.9%, 95% CI 9.6-20.2%, I2 = 66.6%) and vasodilators administration (MD 7.4%, 95% CI 5.2-9.7%, I2 = 62.3%). Closed-loop systems also decreased the duration of recovery after propofol (MD 1.3 min, 95% CI 0.4-2.1 min, I2 = 58.6%) and neuromuscular blockers (MD 9.0 min, 95% CI 7.9-10.0 min, I2 = 0%). The certainty of the evidence was low or very low for most outcomes. Automatic technology may be used to improve the hemodynamic profile during noradrenaline and vasodilators administration and reduce the duration of postanaesthetic recovery.Registration: This systematic review was registered with PROSPERO (CRD42022336950) on the 7th of June 2022.

Accuracy of self-diagnosis in conditions commonly managed in primary care: diagnostic accuracy systematic review and meta-analysis

OBJECTIVES

To assess the diagnostic accuracy of self-diagnosis compared with a clinical diagnosis for common conditions in primary care.

DESIGN

Systematic review.

DATA SOURCES

Medline, Embase, Cochrane CENTRAL, Cochrane Database of Systematic Reviews and CINAHL from inception to 25 January 2021.

STUDY SELECTION

Eligible studies were prospective or retrospective studies comparing the results of self-diagnosis of common conditions in primary care to a relevant clinical diagnosis or laboratory reference standard test performed by a healthcare service provider. Studies that considered self-testing only were excluded.

DATA EXTRACTION

Two authors independently extracted data using a predefined data extraction form and assessed risk of bias using Quality Assessment of Diagnostic Accuracy Studies-2.

METHODS AND RESULTS

5047 records identified 18 studies for inclusion covering the self-diagnosis of three common conditions: vaginal infection (five studies), common skin conditions (four studies) and HIV (nine studies). No studies were found for any other condition. For self-diagnosis of vaginal infection and common skin conditions, meta-analysis was not appropriate and data were reported narratively. Nine studies, using point-of-care oral fluid tests, reported on the accuracy of self-diagnosis of HIV and data were pooled using bivariate meta-analysis methods. For these nine studies, the pooled sensitivity was 92.8% (95% CI, 86% to 96.5%) and specificity was 99.8% (95% CI, 99.1% to 99.9%). Post hoc, the robustness of the pooled findings was tested in a sensitivity analysis only including four studies using laboratory testing as the reference standard. The pooled sensitivity reduced to 87.7% (95% CI, 81.4% to 92.2%) and the specificity remained the same. The quality of all 18 included studies was assessed as mixed and overall study methodology was not always well described.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Overall, there was a paucity of evidence. The current evidence does not support routine self-diagnosis for vaginal infections, common skin conditions and HIV in primary care.

PROSPERO REGISTRATION NUMBER

CRD42018110288.

Verification bias

This article is part of the Catalogue of Bias series. We present a description of verification bias, and outline its potential impact on research studies and the preventive steps to minimise its risk. We also present teaching slides in the online supplementary file. Verification bias (sometimes referred to as 'work-up bias') concerns the test(s) used to confirm a diagnosis within a diagnostic accuracy study. Verification bias occurs when only a proportion of the study participants receive confirmation of the diagnosis by the reference standard test, or if some participants receive a different reference standard test.

Trials of transvaginal mesh devices for pelvic organ prolapse: a systematic database review of the US FDA approval process

INTRODUCTION

Transvaginal mesh devices are approved in the USA by the Food and Drug Administration (FDA), through the 510(k) system. However, there is uncertainty about the benefit to harm balance of mesh approved for pelvic organ prolapse. We, therefore, assessed the evidence at the time of approval for transvaginal mesh products and the impact of safety studies the FDA mandated in 2012 because of emerging harms.

METHODS

We used FDA databases to determine the evidence for approval of transvaginal mesh. To create a 'family tree' of device equivalence, we used the 510(k) regulatory approval of the 1985 Mersilene Mesh (Ethicon) and the 1996 ProteGen Sling (Boston Scientific), searched for all subsequently related device approvals, and for the first published randomised trial evidence. We assessed compliance with all FDA 522 orders issued in 2012 requiring postmarketing surveillance studies.

RESULTS

We found 61 devices whose approval ultimately relied on claimed equivalence to the Mersilene Mesh and the ProteGen Sling. We found no clinical trials evidence for these 61 devices at the time of approval. Publication of randomised clinical trials occurred at a median of 5 years after device approval (range 1-14 years). Analysis of 119 FDA 522 orders revealed that in 79 (66%) the manufacturer ceased market distribution of the device, and in 26 (22%) the manufacturer had changed the indication. Only seven studies (six cohorts and new randomised controlled trial) covering 11 orders were recruiting participants (none had reported outcomes).

CONCLUSIONS

Transvaginal mesh products for pelvic organ prolapse have been approved on the basis of weak evidence over the last 20 years. Devices have inherited approval status from a few products. A publicly accessible registry of licensed invasive devices, with details of marketing status and linked evidence, should be created and maintained at the time of approval.

Ten essential papers for the practice of evidence-based medicine

In this article we signpost readers to 10 papers we consider essential reading for anyone starting out on an evidence-based medicine journey. We have considered papers consisting a mix of old and new, seminal and cutting-edge that offer insight into what evidence-based medicine is, where it came from, why it matters and what it has achieved. This is balanced against some of the common criticisms of evidence-based medicine and efforts to tackle them. We have also highlighted papers acknowledging the importance of teaching and learning of the principles of evidence-based medicine and how health professionals can better use evidence in clinical decisions with patients.

Identification of scavenger receptor ligands

Scavenger receptors (SRs) are structurally diverse but functionally related innate immune receptors involved in defence and clearance mechanisms. Their broad specificity relies on evolutionarily conserved pattern recognition domains which interact with a variety of microbial, apoptotic and modified self ligands. Studies of immune functions of SR-expressing cells require the identification of interaction partners for SRs. We have developed an ELISA-based method which allows for large-scale high-throughput screening of complex mixtures. The assay successfully identified bacterial and plasma ligands for macrophage scavenger receptor A and can be adapted to screen for novel exogenous or endogenous ligands for any immune receptor of interest.