Evaluating the Effect of Nursing-Performed Point-of-Care Ultrasound on Septic Emergency Department Patients.

Introduction Nursing-performed point-of-care ultrasound (NP-POCUS) studies have been performed on applications such as ultrasound-guided peripheral intravenous line placement and assessing bladder volume. However, research on the use of NP-POCUS in the management of septic patients remains limited. The purpose of this quality improvement study was to investigate how NP-POCUS could impact fluid treatment decisions affecting septic patients in the emergency department (ED) using a focused IVC and lung ultrasound protocol. Methods Nurses received standardized training in POCUS and performed inferior vena cava (IVC) and lung ultrasound scans on septic patients in the ED at predetermined intervals (hours: zero, three, and six). Based on their findings, they were asked to make recommendations on fluid management. Emergency physicians (EPs), both residents and attendings, are providing recommendations for fluid management without the use of ultrasound, which is being compared to the nurse-driven POCUS assessment of fluid management. EPs reviewed the NP-POCUS assessments of patient fluid status to determine nursing accuracy. Results A total of 104 patients were scanned, with a mean age of 60.7 years. EPs agreed with nursing ultrasound assessments in 99.1% of cases. Nursing ultrasound images changed management or increased physician confidence in current treatment plans 83.7% and 96.6% of the time, respectively. Before reviewing saved nursing ultrasound images, EPs underestimated fluid tolerance in 37.5% of cases, overestimated fluid tolerance in 26% of cases, and correctly estimated fluid tolerance (within 500 ml) in 36.5% of cases. Throughout resuscitation, IVCs became less collapsible, the number of cases with B-lines was essentially unchanged, and less fluid was recommended. Conclusion  This study demonstrated that nurse-performed POCUS is feasible and may have a meaningful impact on how physicians manage septic patients in the emergency department.

Efficient targeting of fatty-acid modified oligonucleotides to live cell membranes through stepwise assembly.

Lipid modifications provide efficient targeting of oligonucleotides to live cell membranes in a range of applications. Targeting efficiency is a function of the rate of lipid DNA insertion into the cell surface and its persistence over time. Here we show that increasing lipid hydrophobicity increases membrane persistence, but decreases the rate of membrane insertion due to the formation of nonproductive aggregates in solution. To ameliorate this effect, we split the net hydrophobicity of the membrane anchor between two complementary oligonucleotides. When prehybridized in solution, doubly anchored molecules also aggregate due to their elevated hydrophobicity. However, when added sequentially to cells, aggregation does not occur so membrane insertion is efficient. Hybridization between the two strands locks the complexes at the cell surface by increasing net hydrophobicity, increasing their total concentration and lifetime, and dramatically improving their utility in a variety of biomedical applications.

Chemically programmed cell adhesion with membrane-anchored oligonucleotides.

Cell adhesion organizes the structures of tissues and mediates their mechanical, chemical, and electrical integration with their surroundings. Here, we describe a strategy for chemically controlling cell adhesion using membrane-anchored single-stranded DNA oligonucleotides. The reagents are pure chemical species prepared from phosphoramidites synthesized in a single chemical step from commercially available starting materials. The approach enables rapid, efficient, and tunable cell adhesion, independent of proteins or glycans, by facilitating interactions with complementary labeled surfaces or other cells. We demonstrate the utility of this approach by imaging drug-induced changes in the membrane dynamics of non-adherent human cells that are chemically immobilized on a passivated glass surface.