Standard Insertion Research Articles

Efficient extraction of hierarchical B-Splines for local refinement and coarsening of Isogeometric Analysis

The main motivation for hierarchical B-Splines in Isogeometric Analysis is to perform a local refinement that is globally not a tensor product. Compared to standard knot insertion, this allows to increase refinement locality. Moreover, the implementation of hierarchical refinement on existing codes can be facilitated by Bézier extraction. This approach was initially developed for unrefined patches and then extended to local refinement. In case of B-Spline patches that are not locally refined, extraction and projection algorithms can be optimized by leveraging the tensor structure. However, these optimizations are not straightforwardly applicable to hierarchical B-Splines.In this contribution, we show an approach where all extraction operations are formulated to work directly on the univariate extraction operators, without explicitly computing and storing the full tensor product. In particular, we consider the extraction of functions, and projection of degrees of freedom for refinement and coarsening. A slightly modified Bézier projection is proposed to fully exploit the developed algorithms. We finally compare our approach to an explicit computation of the extraction operator in both a linear transient and a nonlinear example.

Impedimetric melanoma invasion assay device using a simple paper membrane and stencil-printed electrode on PMMA substrate

The transwell assay is currently the most popular approach to studying cellular invasion due to its ease of use and readout, and the possibility for quantitative measurements. However, it only allows end-point measurements without the possibility for real-time tracking of the dynamics of cell movement during an invasion. Moreover, it requires cell labeling, and construction of customized devices is hampered by the commercial standard membrane inserts, only available in certain designs. Recently, paper has been used as a scaffold for three-dimensional (3D) cell cultures. Because of its microfibrous structure and easy handling, it could be a versatile alternative as a membrane insert in customized devices. Here, we develop a low-cost real-time invasion assay device using paper as an alternative membrane insert. The device was designed for two-electrode impedance measurements and fabricated using CNC micromilling. It also comprised a disposable low-cost stencil-printed working electrode on a poly(methyl methacrylate) substrate below the membrane and glassy carbon counter electrode above the membrane inserted in a specially designed lid. Thus, the impedance measurements during cell invasion addressed the entire membrane. We demonstrated the function of the device by monitoring the invasion of B16 melanoma 4A5 cells from a mouse using insulin growth factor-1 as the chemoattractant. The cell invasion on paper was visualized using scanning electron microscopy and confocal microscopy with Z-stack 3D imaging. Melanoma cell invasion could be observed within 7 h after the chemoattractant treatment, which was faster than the conventional assay and less likely to be influenced by cell proliferation.

The effect of probe geometry on rind puncture resistance testing of maize stalks

BackgroundStalk lodging (breaking of plant stems prior to harvest) is a major impediment to increasing agricultural yields of grain crops. Rind puncture resistance is commonly used to predict the lodging resistance of several crop species. However, there exist no standard operating procedures or suggested protocols for conducting rind penetration experiments. In addition, experimental details of rind penetration tests such as the shape and size of the penetrating probe are rarely reported in the literature. This has prevented meta-analysis of results and has likewise prevented key findings of past studies from being replicated. As a first step towards establishing an agreed upon measurement standard for rind puncture resistance this study investigates the effect of the puncturing probe’s geometry on test results.ResultsResults demonstrate that probe geometry has a significant impact on test results. In particular, results showed that a 2 mm diameter chamfered probe produced stronger correlations with stalk bending strength than a 1.5 mm diameter pointed probe. The chamfered probe was also more strongly correlated with geometric features of the stalk that are known to influence stalk lodging resistance (e.g., rind thickness, diameter and section modulus). In addition, several alternative rind penetration metrics were investigated, and some were found to be superior to the most common rind penetration metric of maximum load.ConclusionsThere is a need in the agricultural and plant science community to create agreed-upon operating procedures and testing standards related to mechanical traits of plant stems. In particular, a standardized probe geometry and insertion rate for rind penetration studies are needed to enable greater interoperability and meta-analysis of results. Probe shape and size should be reported in any study conducting rind penetration tests as these factors significantly impact test results.

Analytical Magnetic Model Towards Compact Design of Magnetically-Driven Capsule Robots

This work proposes a magnetic model for interaction forces and torques calculation between two permanent magnets applied in external magnetically-driven capsule endoscopies. The internal permanent magnet (IPM) embedded in the robotic capsule is characterized as a truncated cylinder which is beneficial to increase the efficiency of the internal space distribution of the capsule, especially for an active capsule robot integrated with medical functions like imaging, standard medical tool insertion, etc. In this paper, the second central moment is used first as the evaluation parameter to choose the shape of the IPM, i.e., the truncated cylinder, considering the demanding efficiency of the internal space of a capsule. Then, the analytical magnetic forces and torques model for the truncated cylinder-shaped permanent magnet has been reported and validated by comparison of results from the proposed magnetic model developed in MATLAB and the software of COMSOL Multiphysics. The experiments are presented in the end to demonstrate that the compact design of the capsule robot with a truncated cylinder-shaped IPM can work effectively and efficiently.

Antistasis Retrograde Flow Vascular Catheter: A Novel Solution to Thrombogenicity: A Computational Fluid Dynamics Study.

Catheter-related thrombosis (CRT) is a serious complication of vascular catheters. Retrograde catheter insertion has been shown to decrease pericatheter hemostasis and thrombosis, but it is technically challenging. The current in silico trial is an analytical approach to evaluating different approaches to designing retrograde flow into a vascular catheter. The novel catheter design aims to provide antistasis retrograde flow (ASRF) of fluid through multiple backward-directed side openings, with a self-closing terminal opening to facilitate standard insertion. Four different models of the catheter were evaluated by computational fluid dynamic studies, with retrograde-angled openings of 15°, 30°, 45°, and 60° to the long axis of the catheter. ASRF successfully reduced the areas of fluid stagnation in models with 15° and 30° openings. Models with 45° and 60° did not significantly reduce stagnation. ASRF is reversed by the main bloodstream after a few millimeters. The novel catheter design achieved a slightly higher saline flow rate compared with the standard catheter (89.75, 91.72, 94.13, and 94.26 mL/min for 15°, 30°, 45°, and 60° designs, respectively, versus 86.93 mL/min for the standard catheter). The novel ASRF vascular catheter reduces pericatheter fluid stasis and has the potential to reduce CRT. Further in vitro and in vivo trials are warranted to validate these findings and evaluate clinical efficacy.

Reduction of Test Time using Multiple Test Control Point Insertion for 7nm Technology Node

Test time reduction is a prominent challenge in scan based Design For Testability (DFT) architectures for cost effective test. Reliability and testability both are main objectives for DFT in today’s VLSI design. In this paper, we have proposed multiple standard test control point insertion technique for 7nm technology node. The design was tested on 7828 sequential cells. We have compared results of following three Design Rule Check (DRC) (1) Scan DRC (2) Clock Scan DRC (3) Multiple standard test control point insertion DRC. We have used software tool Synopsys TetraMAX ATPG, Synopsys DFTMAX and Synopsys DFT compiler to verify the design. It has been observed that multiple standard test control point insertion DRC takes minimum time to check design of 7828 sequential cells.

Impact of balloon inflation on the insertion of endoscopic ultrasound: a prospective, randomized controlled trial.

Background and study aims During endoscopic ultrasound (EUS), patients may experience severe discomfort. The radial echoendoscope has a balloon around its tip. Balloon inflation prior to insertion may reduce contact injury and pharyngeal pain. The purpose of this study was to investigate the effect of balloon inflation on pharyngeal pain during insertion. Patients and methods Patients who underwent radial EUS for pancreatobiliary disease were randomized into standard insertion or balloon-inflated insertion. The primary outcome was the proportion of moderate-to-severe pharyngeal pain. Secondary outcomes were the degree of pharyngeal pain, risk factors for moderate pharyngeal pain, procedure-related adverse events, and pharyngeal pain depending on the experience of the endoscopist. Results A total of 481 patients were randomized into two groups: standard insertion (238) and balloon inflation (243). No statistically significant differences in proportion of moderate-to-severe pain were found (26.5 % vs. 20.2 %, P = 0.107). Balloon inflation (HR 0.65; 95 % CI (0.42–0.98, P = 0.041) was a protective factor against moderate pain. Balloon inflation reduced the proportion of patients with moderate-to-severe pain when performed by physicians with less than 3months of experience with EUS (44.7 % vs. 25.3 %, P = 0.012). Conclusion Balloon inflation did not reduce the absolute degree of post-procedural pain with EUS, but it reduced the number of patients with moderate-to-severe pain when performed by physicians with less than 3 months of experience.

Cytotoxic, Antimicrobial, Antioxidant Properties and Effects on Cell Migration of Phenolic Compounds of Selected Transylvanian Medicinal Plants.

Medicinal plants are widely used in folk medicine but quite often their composition and biological effects are hardly known. Our study aimed to analyze the composition, cytotoxicity, antimicrobial, antioxidant activity and cellular migration effects of Anthyllis vulneraria, Fuchsia magellanica, Fuchsia triphylla and Lysimachia nummularia used in the Romanian ethnomedicine for wounds. Liquid chromatography with mass spectrometry (LC-MS/MS) was used to analyze 50% (v/v) ethanolic and aqueous extracts of the plants’ leaves. Antimicrobial activities were estimated with a standard microdilution method. The antioxidant properties were evaluated by validated chemical cell-free and biological cell-based assays. Cytotoxic effects were performed on mouse fibroblasts and human keratinocytes with a plate reader-based method assessing intracellular adenosine triphosphate (ATP), nucleic acid and protein contents and also by a flow cytometer-based assay detecting apoptotic–necrotic cell populations. Cell migration to cover cell-free areas was visualized by time-lapse phase-contrast microscopy using standard culture inserts. Fuchsia species showed the strongest cytotoxicity and the highest antioxidant and antimicrobial activity. However, their ethanolic extracts facilitated cell migration, most probably due to their various phenolic acid, flavonoid and anthocyanin derivatives. Our data might serve as a basis for further animal experiments to explore the complex action of Fuchsia species in wound healing assays.

Fiber interferometer based on standard fiber spliced between two thin-core insertions

Abstract A new type of fiber interferometer based on two short thin-core fiber insertions with a section of standard fiber in between is proposed. The thin-core fiber insertions excite cladding modes and provide energy exchange between different fiber modes. We have simulated and measured transmission through a single thin-core fiber section. The standard fiber section is used to accumulate phase differences between core and cladding modes propagating through the structure. Transmission spectra are measured for various lengths of the interferometer. Separate control of thin-core and standard fiber insertions adds flexibility in obtaining spectra desirable for sensing applications.

Evaluating an ultrasound-guided peripheral intravenous cannulation training program for emergency clinicians: An Australian perspective

ObjectiveThe primary objective of this study was to identify the proportion of clinicians using ultrasound guidance (USG) to insert peripheral intravenous cannulas (PIVCs) in the emergency department (ED) following attendance at a hospital-based USG PIVC training program. MethodsOver 12-months, USG cannulation training sessions were offered to nurses and doctors competent in standard PIVC insertion (landmark technique), working in the ED. Surveys pre and post-training captured participants’ self-reported confidence with cannulation and USG cannulation using a 5-point Likert scale. Supplemental data from observation periods before and after the trainings assessed departmental cannulation practices overall. Data were analysed using descriptive statistics and associations analysed using chi-square tests. ResultsOverall, 195 participants attended training; 58% completed follow-up surveys. Forty-three percent reported using USG cannulation the following month. The median confidence score amongst workshop participants increased from 1 to 3 (p<.001). Post-implementation, use of USG cannulation increased from 0.7% to 6.0% post-training (p<.001), although the overall number of attempts at PIVC placement did not change. ConclusionsUSG cannulation training increased this practice in the short-term. However, no significant difference in the number of attempts was observed. Further investigation in controlled settings is needed to inform the widespread implementation of USG cannulation training packages.

Comparison of the insertion of LMA classicTM by the standard insertion technique Vs the 90-degree rotational technique - A prospective randomised comparative study

Comparison of the insertion of LMA classicTM by the standard insertion technique Vs the 90-degree rotational technique - A prospective randomised comparative study

Comparison of Primary Stability of Implants Installed by Two Different Methods in D3 and D4 Bone Types: An In Vitro Study.

ABSTRACTObjective:The purpose of the study is to assess the method of implant insertion in D3 and D4 bones and influence of insertion torque for achieving better primary implant stability.Materials and Methods:A total of 32 specimens (wood blocks) simulating D4 and D3 bone were grouped into 1, 2, 3, and 4. In groups 1 and 3, the implant and abutment were placed by manual method while in groups 2 and 4 by motor-driven method. The osteotomy site was prepared as per the protocol for soft bone, and implants were placed till the implant platform was in flush with the surface of the block. After achieving a standard insertion torque of 40 N.cm, pullout test was carried out with a universal testing machine and results were analyzed by one-way analysis of variance.Results:An intergroup comparison of peak loads revealed an overall statistically significant difference (P < 0.0001) with a mean of 442.638 N, maximum in group 4 and least (202.963 N) in group 1. The mean elongation break was found to be maximum in group 3 samples (81.67600%) and less in group 4 (37.15113%). Intergroup comparison of Young’s modulus was statistically significant (P < 0.0001) with a mean value found to be minimum among group 1 samples (597.54750 MPa) and maximum in group 2 (1056.76463 MPa). An intergroup comparison of yield points was found to be maximum among group 4 samples (16.17238MPa) and least in group 1 (5.77438MPa).Conclusion:The D3 bone sample provided greater primary stability of implant than D4 bone samples, and the motor-driven implant seemed to have improved stability than that placed manually.

Computational wear prediction of insert conformity and material on mobile-bearing unicompartmental knee arthroplasty.

ObjectivesUnicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty with isolated medial or lateral compartment osteoarthritis. However, polyethylene wear can significantly reduce the lifespan of UKA. Different bearing designs and materials for UKA have been developed to change the rate of polyethylene wear. Therefore, the objective of this study is to investigate the effect of insert conformity and material on the predicted wear in mobile-bearing UKA using a previously developed computational wear method.MethodsTwo different designs were tested with the same femoral component under identical kinematic input: anatomy mimetic design (AMD) and conforming design inserts with different conformity levels. The insert materials were standard or crosslinked ultra-high-molecular-weight polyethylene (UHMWPE). We evaluated the contact pressure, contact area, wear rate, wear depth, and volumetric wear under gait cycle loading conditions.ResultsConforming design inserts had the lower contact pressure and larger contact area. However, they also had the higher wear rate and volumetric wear. The improved wear performance was found with AMD inserts. In addition, the computationally predicted volumetric wear of crosslinked UHMWPE inserts was less than half that of standard UHMWPE inserts.ConclusionOur results showed that increasing conformity may not be the sole predictor of wear performance; highly crosslinked mobile-bearing polyethylene inserts can also provide improvement in wear performance. These results provide improvements in design and materials to reduce wear in mobile-bearing UKA.Cite this article: Bone Joint Res 2019;8:563–569.

Uncemented megaprosthesis stem fixation using “Scratch Fit” to achieve improved implant fixation

Background: Despite a proposed lower incidence of aseptic loosening, uncemented distal femoral implants present challenges with the intra-operative assessment of the adequacy of stem fixation within the femoral canal. Our biomechanical study was intended to assess the adequacy of oncologic implant press-fit stem fixation within the reamed canal of the distal femur for the Stryker GMRS oncologic distal femoral implant. We hoped to answer the following: #1 Does the initial stem placement in the femoral canal using a standardized force (50 N) (i.e., “Scratch Fit”) predict the (adequacy)stability of the final stem placement (and implant fixation) within the femoral canal? #2 Is there a difference in the uncemented stem fixation and stability within the femur for different stem (Stryker GMRS) diameters (13, 14, and 15 mm) for the Stryker GMRS uncemented press-fit stems/(Stryker Global Orthopaedics) Methods: Femoral cadaveric specimens were thawed and cut at the distal end of the femur, at 13 cm from the distal joint line, to e represent a distal femoral tumor resection. Stryker GMRS uncemented stems were placed, after femoral reaming, into the distal femoral canal with firm, hand pressure applied via a customized, spring-based insertion tool positioned over the standard Stryker insertion tool and calibrated to apply a standard stem insertion force of 50 N (11.2 lbs). Initial stem placement, utilizing this method, resulted in a stem that was only partially implanted into the femur with a recorded distance (defined as “Scratch Fit”) between the stem collar and the cut surface of the femoral shaft. After completing final stem impaction into the femur, stem torsional testing was performed on a multi-axis biomechanical test frame with a 3-D Vicon motion-capture system with axial torsion applied to the stems with the proximal femur fixed to a potted base. Kinematics of both the implant and the distal femur were captured using the Vicon system which tracked reflective infrared targets at a 60 Hz sampling rate. The peak torsional moment at failure was compared to “Scratch Fit” metrics for each implant diameter to address the proposed research questions. Results: Scratch fit distances ranged from 7–46 mm with a mean of 29.1±12.7 mm. Peak torques ranged from 11.5 to 57.5 Nm with a mean of 33.6±17.0 Nm. Figure shows peak (max.) torque plotted against scratch fit for all stems/specimens with good correlation (r 2 =0.6404). When separated by stem diameters, figure shows strong correlations between peak torque and scratch fit. Conclusions: while there may be multiple metrics that affect uncemented stem implant placement and stability (i.e., femoral canal size, femoral reaming, and implant type/size (diameter), there appears to be some correlation between initial stem placement (i.e., “Scratch Fit”) after femoral reaming to implant torsional (rotational) stability; this correlation is stronger when controlled for stem diameter. This suggests that a greater initial “Scratch Fit” distance may provide improved press-fit stem fixation and may provide a better operative standard for making decisions regarding the fixation or stability of these implants.

Self-Supplied Liquid Injection Field Desorption/Ionization Ion Source for an Orthogonal Time-of-Flight Instrument.

A new implementation of a dedicated ion source for field ionization (FI), field desorption (FD), and liquid injection field desorption/ionization (LIFDI) for the JEOL AccuTOF GC series of orthogonal-acceleration time-of-flight instruments is presented. In contrast to existing implementations, this third-party LIFDI probe and source combination does not require the exchange of the entire ion source comprising ion source block and lens stack to switch from electron ionization (EI) to LIFDI. Rather, the methods may be swapped conveniently by only exchanging the ion source block for a mechanical probe guide and inserting the LIFDI probe in place of the standard direct insertion probe (DIP) via the vacuum lock. Further, this LIFDI setup does not require any changes of the electronics or software of the AccuTOF mass spectrometer because it is self-supplied in terms of power supply, observation optics, and computer control. The setup offers advanced FI/FD/LIFDI control features such as emission-controlled emitter heating current and emitter flash baking during elongated runs as required for gas chromatography-FI-mass spectrometry (MS). The LIFDI source and probe and its operation are reported in detail. FI spectra of the volatile analytes toluene, heptane, and pentafluoroiodobenzene are presented. LIFDI operation is demonstrated for the analysis of the saturated hydrocarbon dotriacontane and the low-mass hydrocarbon polymers polystyrene 484 and polystyrene 1050. Further, the air-sensitive 2nd-generation Hoveyda-Grubbs catalyst is analyzed by LIFDI-MS. For comparison with long-established LIFDI instrumentation, some of the spectra obtained with the new setup are also compared with those from a double-focusing magnetic sector instrument.

Surgicoanatomical aspect in vascular variations of the V3 segment of vertebral artery as a risk factor for C1 instrumentation

ObjectAwareness of vascular anomalies in V3 segment of vertebral artery (VA) is crucial to avoid iatrogenic injuries during surgical procedure. This study aimed to analyze the incidence of V3 segment vascular variations and demonstrate the importance of deciding the surgical strategy for C1 screw placement. MethodsPrevalence of vascular variations and morphometric measurements of the VA in the region of the craniocervical junction in 200 cases based on three-dimensional computed tomographic angiography (3D-CTA) scans were studied. ResultsThe VA has a variable course through C2 before it passes above its groove on the posterior arch of C1. Following the vascular variations of V3 segments of VA were persistent including first intersegmental artery (FIA), fenestration (FEN) of the VA, high-riding (HRVA and the posterior inferior cerebellar artery (PICA) branch originating from the C1/2 part of VA. HRVA was observed in 10.1% of patients, FIA in 1.8%, FEN in 1.3%, and PICA in 1.3%. One hundred and twenty-three (24.1%) patients were identified to have HRVA, 6% present on both sides. ConclusionThe VA with FIA and FEN were rare in this study as many as a 10% the VA present over the starting point for C1 lateral screw. With respect to the vascular anatomy of V3 and more frequent left-sided VA dominancy, standard screw insertion should be started from the right side. Routine preoperative 3D-CTA evaluation is mandatory to prevent the VA injury when C1-C2 instrumentation is planned.

Urgent-start peritoneal dialysis for patients with end stage renal disease: a 10-year retrospective study

BackgroundUrgent-start peritoneal dialysis (PD) can help patients with end-stage renal diseases (ESRD) that are referred late to dialysis. However, catheter patency and related complications of urgent-start PD have not been thoroughly clarified. We investigated the clinical outcomes of urgent-start PD in a Chinese cohort.MethodsWe enrolled ESRD patients who received urgent-start PD (starting PD within 14 days after catheter insertion) in our center from January 1, 2006 to December 31, 2014, and followed them up for 10 years. The primary outcome was catheter failure. Secondary outcomes included short-term and long-term complications related to urgent-start PD.ResultsTotally 2059 patients (58.9% male, mean age 47.6 ± 15.9 years) were enrolled. Few perioperative complications were observed, including significant hemorrhage (n = 3, 0.1%) and bowel perforation (n = 0). Early peritonitis occurred in 24 (1.2%) patients (0.28 episodes per patient-year). Within the first month after catheter insertion, functional catheter malfunction occurred in 85 (4.1%) patients, and abdominal wall complications (including hernia, hydrothorax, hydrocele, and leakage) in 36 (1.7%) patients. During a median 36.5 (17.7–61.4) months of follow-up, 75 (3.6%) patients experienced catheter failure, and 291 (14.1%) had death-censoring technique failure. At the end of 1-month, 1 -year, 3-year, and 5-year, catheter patency rate was 97.6, 96.4, 96.2, 96.2%; and technique survival rate was 99.5, 97.0, 90.3, 82.7%, respectively. After adjusting for confounders, every 5-year increase in age was associated with 19% decrease of risk for catheter failure (hazard ratio [HR]: 0.81, 95% confidence interval [CI]: 0.73–0.89). Male sex (HR: 1.43, 95% CI: 1.00–2.04), diabetic nephropathy (HR: 1.56, 95% CI: 1.08–2.25) and low hemoglobin levels (HR: 0.89, 95% CI: 0.81–0.98) were independent risk factors for abdominal wall complications.ConclusionsUrgent-start PD is a safe and efficacious option for unplanned ESRD patients. A well-trained PD team, a standardized catheter insertion procedure by experienced nephrologists, and a carefully designed initial PD prescription as well as comprehensive follow-up care, might be essential for the successful urgent-start PD program.

Intracochlear Pressure Transients During Cochlear Implant Electrode Insertion: Effect of Micro-mechanical Control on Limiting Pressure Trauma.

Use of micro-mechanical control during cochlear implant (CI) electrode insertion will result in reduced number and magnitude of pressure transients when compared with standard insertion by hand. With increasing focus on hearing preservation during CI surgery, atraumatic electrode insertion is of the utmost importance. It has been established that large intracochlear pressure spikes can be generated during the insertion of implant electrodes. Here, we examine the effect of using a micro-mechanical insertion control tool on pressure trauma exposures during implantation. Human cadaveric heads were surgically prepared with an extended facial recess. Electrodes from three manufacturers were placed both by using a micro-mechanical control tool and by hand. Insertions were performed at three different rates: 0.2 mm/s, 1.2 mm/s, and 2 mm/s (n = 20 each). Fiber-optic sensors measured pressures in scala vestibuli and tympani. Electrode insertion produced pressure transients up to 174 dB SPL. ANOVA revealed that pressures were significantly lower when using the micro-mechanical control device compared with insertion by hand (p << 0.001). No difference was noted across electrode type or speed. Chi-square analysis showed a significantly lower proportion of insertions contained pressure spikes when the control system was used (p << 0.001). Results confirm previous data that suggest CI electrode insertion can cause pressure transients with intensities similar to those elicited by high-level sounds. Results suggest that the use of a micro-mechanical insertion control system may mitigate trauma from pressure events, both by reducing the amplitude and the number of pressure spikes resulting from CI electrode insertion.

Putting the Cap on Central Line–Acquired Bloodstream Infections

Our quest for zero central line–acquired bloodstream infections (CLABSIs) began in the fall of 2017. Using the model for improvement from the Institute of Healthcare Improvement helped navigate our initial goal to reduce the CLABSI rate from 2/1,000 catheter days to 1/1,000 catheter days. This nurse-led CLABSI project was designed to address two key drivers: (a) Create a culture of accountability and safety and (b) increase communication, understanding, and use of the CLABSI insertion and maintenance bundles. Setting small, attainable goals stimulated staff nurses’ passions to achieve success. The NICU CLABSI quality improvement team included bedside nurses, the NICU nursing director, medical providers, and NICU peripherally inserted central catheter (PICC) team nurses. Interventions to decrease risk of CLABSI included adherence to standardized practices for central line care while systematically introducing standardized CLABSI insertion and maintenance bundles. Staff audits, readiness rounds, electronic medical record changes, and peer-to-peer audits ensured improved nursing knowledge of central lines. A data board aided in staff and family communication and created transparency of our quality improvement work. Data were collected in standardized format according to Centers for Disease Control and Prevention criteria and compared with historical NICU CLABSI rates. Our CLABSI rate decreased by 50% from September 2017 through August 2018. We are currently 345 days without a CLABSI in our NICU. Using key drivers, with each tied to multiple interventions and tested using plan–do–study–act cycles, made our work meaningful. The meticulous attention to CLABSI bundle processes and audits of each measure assured a reliable level of hardwiring changes; in addition, these interventions yielded a dramatic effect on nursing staff accountability. Our clinical standards focused on insertion as well as maintenance bundle elements, using highly reliable methods. Tools such as visual reminders of bundle elements, line-necessity discussions led by nurses, and daily nursing and multidisciplinary huddles to ensure nurse accountability consistently yielded greater than 95% reliability of implementation of each bundle element.

First results of multicortical screw anchoring compared with conventional bicortical screw placement in the sacrum: A biomechanical investigation of a new screw design

BackgroundBicortical screw fixation is an established technique to increase screw strength in vertebral bodies, although it is associated with several complications, for example screw-loosening. Cement augmentation can increase stability of screw-fixation but can also cause various complications, such as cement-leakage or cement embolism. In this study, we tested a new, multicortical screw fixation technique in the sacrum. MethodsFour fresh-frozen sacrums were used. In group 1, standard screw insertion, with sagittal parallel and axial convergent screw-drive was performed. In group 2, the screw-drive of the first screw was similar to the screw-drive in group 1. In addition, a second screw was inserted descending into the intended hole in the head of the screw and at a stable angle. Therefore, the screws of the multiloc humerus nail-system (Synthes) were used. The specimens were connected to a testing-machine and underwent cyclic axial loading with an increase in the load after each completed stage. FindingsMulticortical screw fixation leads to a significant increase in the number of completed cycles and a significantly increased load until failure. InterpretationMulticortical screw fixation in the sacrum offers a stronger attachment of the screws. In the future, multicortical implants, which fulfil the criteria demanded in spine surgery, can offer higher stability and may decrease the loosening rates of the implanted screws.