Standard Insertion Research Articles

Nurse initiated reinsertion of nasogastric tubes in the Emergency Department: A randomised controlled trial

Patients sometimes present to the Emergency Department (ED) for reinsertion of nasogastric tubes (NGT) because of tube dislodgement. They usually need to wait for a long time to see a doctor before the NGT can be reinserted. This study aimed at investigating the feasibility of nurse initiated NGT insertion for these patients in order to improve patient outcome. This is a prospective randomised controlled trial. Patients requiring NGT reinsertion were randomised to receive treatment by either nurse initiated reinsertion of NGT (NIRNGT) or the standard NGT insertion protocol. Questionnaires were given to both groups of patients, relatives and ED nurses afterwards. Outcome measures included door-to-treatment time, total length of stay (LoS) in the ED and the satisfaction of patients, relatives and nurses. Twenty-two patients were recruited to the study and randomised: 12 in the standard NGT insertion protocol and 10 in the NIRNGT protocol. The door-to-treatment time of the NIRNGT group (mean=45.6 min) was significantly shorter than the standard NGT insertion group (mean=123.08 min; p=0.003). No statistically significant difference was detected between the total ED LoS (p=0.575). Patients, relatives and nurses were generally satisfied with the new treatment protocol. Patients can undergo NGT reinsertion significantly faster by adopting a nurse initiated reinsertion of NGT (NIRNGT) protocol.

Assessment of Pedicle Bone Strength in the Lumbar Spine Using a “Smart” Ball Tip Probe

Preoperative assessment of bone mineral density (BMD) via dual X-ray absorptiometry (DEXA) has been shown to help determine the need for screw augmentation, particularly in the pedicle. However, patients frequently present without preoperative DEXA scans, especially in trauma situations. We developed a “smart” probe for intra-operative assessment of local bone strength in the pedicle. A standard ball tip probe was instrumented with an in-line load cell and was used to test the bone strength of fresh-frozen human cadaveric lumbar spine. Local bone crush strength was assessed using the probe at five locations within the centrum and the pedicle. The contralateral pedicle was outfitted with a standard pedicle screw and insertion torque and pull-out force of the screw were measured. Correlation was found between PS-centrum (probe strength-centrum) and screw pull-out strength (adj. R2 = 0.42). A stepwise linear regression revealed that when considering BMD, insertion torque, and PS-centrum, pull-out strength could be predicted based on PS-centrum and insertion torque (adj. R2 = 0.51, p < 0.01, Fisher test). The results suggest that use of the new probe may be a more quantitative measurement of screw purchase when DEXA is unavailable, such as in spinal trauma cases. Furthermore, when used in conjunction with DEXA, the “smart” ball tip probe may improve assessment of the strength of pedicle screw purchase.

Weak heaps engineered

A weak heap is a priority queue that supports the operations construct, minimum, insert, and extract-min. To store n elements, it uses an array of n elements and an array of n bits. In this paper we study different possibilities for optimizing construct and insert such that minimum and extract-min are not made slower. We provide a catalogue of algorithms that optimize the standard algorithms in various ways. As the optimization criteria, we consider the worst-case running time, the number of instructions, branch mispredictions, cache misses, element comparisons, and element moves. Our contributions are summarized as follows:1.The standard algorithm for construct runs in O(n) worst-case time and performs n−1 element comparisons. Our improved algorithms reduce the number of instructions, the number of branch mispredictions, the number of element moves, and the number of cache misses.2(a)Even though the worst-case running time of the standard insert algorithm is logarithmic, we show that—in contrast to binary heaps—n repeated insert operations require at most 3.5n+O(lg2n) element comparisons.2(b)We improve a recent result of ours, in which we achieve O(1) amortized time per insertion, to guarantee O(1) worst-case time per insertion. After the deamortization, minimum still takes O(1) worst-case time and involves no element comparisons, and extract-min takes O(lgn) worst-case time and involves at most lgn+O(1) element comparisons. This constant-factor optimality concerning the number of element comparisons has previously been achieved only by pointer-based multipartite priority queues. We have implemented most of the proposed algorithms and tested their practical behaviour. Interestingly, for integer data, reducing the number of branch mispredictions turned out to be an effective optimization in our experiments.

SU‐E‐T‐419: To Validate Dose Delivery in Static Field Stereotactic Body Radiation Therapy (SBRT) of Lung Cancer

Purpose: To validate dose delivery in static field stereotactic body radiation therapy (SBRT) of lung cancerMethods: An Exradin A16 0.007cc ion chamber, EBT3 Gafchromic film and Fricke‐Xylenol‐Orange‐Gelatin (FXG) gel dose measurements were performed providing measurements for point, planar and volumetric dose comparisons. CT images (GE Lightspeed RT16 CTSIM) of a Quasar respiratory motion phantom (Modus Medical) with stationary and moving inserts were acquired. Respiratory motion was recorded using a Varian RPM system. Standard cedar inserts with 3cm diameter solid tumors for the ion chamber and film, and an in‐house fabricated custom insert for FXG gel were used. Internal target volumes (ITV) were obtained from 4DCT scans. A typical 15BPM, 20mm amplitude peak‐to‐peak breathing pattern for ion chamber; and sinusoidal 15BPM/10mm respiratory cycles for film and gel dosimetry were used. Nine‐field SBRT plans using 6MV beams were calculated on Eclipse treatment planning system (v10.0; Varian). CBCT scans were used to reproduce the treatment setup; and irradiations were performed on a Trilogy (Varian) linear accelerator. Percentage dose difference and gamma analysis for 3% dose difference and 3mm distance‐to‐agreement were used to compare measured and calculated dose distributions. Results: Measured vs. calculated point dose differences (at a point inside the ITV) for the moving insert geometry were −2.1%, −1.5% and −0.5% for the ion chamber, film and gel measurements, respectively. The planar and volumetric gamma analysis of measured and calculated dose distributions for moving insert geometry showed 99.9% agreements for both EBT3 film and FXG gel dosimetry. Similar comparisons for a stationary insert geometry showed 100% and 98.5% agreements for film and gel measurements, respectively. Conclusion: A consistent level of agreement observed between measured and calculated doses for the point, planar and volumetric dose measurements validates the lung SBRT dose delivery. Research funding support provided by the Canadian Institutes of Health Research (CIHR)

High-speed imaging investigation of transient phenomena impacting plasma arc cutting process optimization

In this work, we report on the investigation of selected transient phenomena taking place in plasma arc cutting (PAC) that are relevant for process optimization. High-speed imaging diagnostics is exploited for the characterization of different technological solutions in order to provide deeper insights into torch and process design. In particular, the pilot arc start-up phase is analysed for a 250 A automatic dual-gas torch equipped with electrodes with different shapes of the initial insert recess, revealing that there is no influence of the recess depth on the time for the stabilization of the pilot arc attachment on the cathode insert. The influence of different insert materials, including Ag–Hf and Cu–Zr binary alloys, on erosion during the shut-down phase is investigated at 120 A and reduced emission of material and faster shut-down is found for alloy inserts compared with standard Hf inserts. The start-up and shut-down transients are also investigated during transferred arc operation using a modified nozzle that comprises a viewing port on one side of the nozzle, and pulsing arc behaviour inside the plasma chamber that is correlated with cathode-nozzle voltage oscillations at a frequency of 7.7 kHz is found. Finally, results regarding the influence of different plasma gas diffusers on the arc stability during the cutting initiation phase in a 100 A mono-gas manual torch are reported.

Endovascular Abdominal Aortic Aneurysm Repair to Facilitate Access for Transcatheter Aortic Valve Implantation

Transcatheter aortic valve insertion is an accepted treatment for select patients at high-risk for standard aortic valve insertion. Constraints imposed by the Food and Drug Administration, Centers for Medicare and Medicaid Services, and the PARTNER Trial Executive Committee require a transfemoral approach in certain patients. The presence of aortoiliac aneurysms, occlusive disease, and excessive vessel tortuosity may create difficulties for safe transfemoral access. We report a case in which the limitation of severe iliac artery occlusive disease was overcome by placement of an abdominal aortic endovascular graft that subsequently allowed successful transfemoral access and transcatheter aortic valve implantation.

Performance of diamond inserts in ultra-high precision turning of Cu3Cr3Zr alloy

Copper–chrome–zirconium (Cu3Cr3Zr) alloys can be used in the optics industry to make mould inserts for injection of thermoplastic optical parts such as lenses and windows. The fabrication of optical mould inserts is usually achieved by diamond turning in order to obtain necessary optical surface finish and high form accuracy. This study was undertaken to investigate the tool wear characteristics when ultra-high precision machining of Cu3Cr3Zr with mono-crystalline diamond inserts. In this work, standard non-controlled waviness diamond inserts having nose radius of about 1.5mm, rake angle of negative 5°, clearance angle of 5° and included angle of 60° were used to produce a flat mirror of 50-mm diameter. Wear patterns occurring on the tool flank and rake faces were observed. Diamond tool performance is discussed in terms of possible wear mechanisms. In addition, the tool wear is associated with the acoustic signals emitted during machining. The preliminary results from the SEM analysis show that abrasive wear is a dominant mechanism especially at low feed rates. The study yields some recommendations on the best combination of machining parameters that will result in maximum material removal rates with relatively smallest possible damage to the tool edge.

A Multidisciplinary Approach to Reduce Central Line–Associated Bloodstream Infections

Stony Brook University Hospital (SBUH) joined a Critical Care Learning Collaborative in fall 2004. The collaborative incorporated application of central line and ventilator bundles, multidisciplinary rounding, and daily goal sheets to improve patient outcomes. In a two-year period, the initiative spread to the medical, pediatric, cardiac, and neonatal ICUs. Despite some success, the goal of eliminating central line-associated bloodstream infections (CLABSIs) was not initially realized. In response, SBUH developed a standardized central line insertion credentialing program for residents. After further review of the residual central line infection data, it was evident that many of the lines became infected after day 7 of insertion. Evaluation of the line maintenance process revealed that nursing staff were not accessing the lines using the same level of sterile technique as used during insertion. As a result, a central line maintenance protocol was developed and deployed. After cumulative efforts were undertaken, SBUH's overall CLABSI rate decreased by 59% in a five-year period and by more than 80% in the most recent 12 months. A critical feature of the approach that SBUH followed was to establish buy-in and oversight from the SICU leadership through a multidisciplinary team, which became the "learning laboratory" for many of the subsequent changes in practice. Also, the fundamental role of the Continuous Quality Improvement (CQI) Department's quality management practitioner as facilitator cannot be overstated. "Hardwiring" of process changes augmented sustainability of improvements, as did a change in the health care team's perception of central line infections--that is, from an "unavoidable complication" to "a failure."

Top Loading Cryogen Free Cryostat for Low Temperature Sample Environment

Today almost a quarter of all neutron scattering experiments performed at neutron scattering facilities require sample temperatures below 2 K. However, a global shortage of helium gas can seriously jeopardise low temperature experimental programmes at neutron scattering laboratories. Luckily the progress in cryo-cooler technology offers a new generation of cryogenic systems with significantly reduced consumption and in some cases nearly a complete elimination of cryogens. Here we discuss design and test results of a new cryogen free top-loading cryostat developed through an ISIS and Oxford Instruments collaborative project. The cryostat provides neutron scattering sample environment in the temperature range 1.4–300 K. High cooling power (0.23 W at temperature less than 2 K) achieved at the cryostat’s variable temperature insert heat exchanger allows operation of a standard dilution refrigerator insert in a continuous regime. From a user perspective, the system offers operating parameters very similar to those of an Orange cryostat but without the complication of cryogens.

Effects of a Novel Push-through Technique Using the Implantable Collamer Lens Injector System for Graft Delivery during Endothelial Keratoplasty

PurposeTo investigate effects of a new push-through insertion method for donor lenticules using an injector system on endothelial viability ex vivo and in a clinical case series of endothelial keratoplasty.MethodsAn ex vivo delivery model was used with porcine corneoscleral rims. We compared the endothelial viability in a new push-through insertion method using the Visian Implantable Collamer Lens (ICL) injector versus that of standard forceps-assisted insertion for lenticule delivery. Twenty porcine corneal lenticules were divided into four groups by insertion method and wound size. Vital dye staining was performed and devitalized areas were semi-quantitatively assessed by digital imaging. In the clinical case series, Descemet's stripping endothelial keratoplasty (DSEK) using the push-through method was performed in seven patients and endothelial outcome was determined six months postoperatively.ResultsMean devitalized areas for the push-through method were significantly lower than for forceps-assisted insertion through 3.2 mm incision (23.99 ± 2.17% vs. 50.48 ± 5.07%, p = 0.009) in the ex vivo model. Average endothelial cell counts of donor tissues of patients who underwent DSEK were 26.4% lower six months postoperatively.ConclusionsPush-through delivery of donor lenticules using the Visian ICL injector system appears to be less harmful to endothelial cells than conventional forceps-assisted delivery.

Four Station Knee Simulator Wear Testing Comparing Titanium Niobium Nitride with Cobalt Chrome

A new non-destructive method was applied in order to assess bone integrity. The method is based on measurement of bHypersensitivity to an orthopaedic implant was first published in 1966 and since then, in sensitive patients, is known to cause serious problems in joint replacement surgery. Titanium niobium nitride (TiNbN) can act as a surface coat for knee arthroplasty to “hide” the cobalt chrome (CoCr) femoral component beneath, therefore affording an immunoprivileged state. The aim of this study is to determine the wear properties of titanium niobium nitride against Ultra High Molecular Weight Polyethylene (UHMWPE) compared to cobalt chrome and to examine the metallic alloy surface of knee prostheses after loading cycles using a knee simulator. Three TiNbN coated and one CoCr Vanguard total knee femoral components were articulated against standard UHMWPE grade tibial inserts in the Stanmore-Instron knee simulator. Surface roughness, UHMWPE mass, lowest point, surface profiles and volumetric change were measuredevery one million cycles up to five million cycles. After five million cycles the average roughness of the cobalt chromemedial and lateral femoral condyles was over three times that of the TiNbN coated femoral condyles. There was no obvious difference in weight loss, volume loss or progression of lowest points of the tibial inserts articulating with the TiNbN coated and the cobalt chrome femoral component. Despite a clear reduction in roughness progression over the course of this in vitro test, there was no demonstrable improvement in UHMWPE wear measured gravimetrically or by surface profiling. The TiNbN implant tested may still be of great benefit to patients who are metal sensitive, but the coat offers no benefit in UHMWPE wear.

Femtosecond laser‐assisted cataract surgery compared with conventional cataract surgery

To investigate the safety and efficacy of the Catalys (Optimedica, Santa Clara, CA, USA) femtosecond laser-assisted cataract surgery system compared with conventional phacoemulsification cataract extraction. Prospective, consecutive, parallel cohort study. The first 200 eyes undergoing conventional cataract surgery to the first 200 eyes undergoing femtosecond laser-assisted cataract surgery between April and July 2012. Femtosecond laser-assisted cataract surgery involved anterior capsulotomy and lens fragmentation based on optical coherence tomography-guided treatment mapping. Conventional cataract surgery involved manual continuous curvilinear capsulorhexis. Both procedures were completed by standard phacoemulsification and insertion of an intraocular lens. Effective phacoemulsification time and intraoperative complication rates. Patient demographics were similar between both groups. There was no statistically significant difference in intraoperative complications between femtosecond laser-assisted cataract surgery and conventional surgery. There was one posterior capsule rupture in both groups (0.5%; not significant). One hundred per cent of cases treated with the femtosecond laser had a complete capsulotomy. Vacuum time decreased with experience. Effective phacoemulsification time was reduced by 70% in the femtosecond group (P < 0.0001). Twenty-six cases in the femtosecond group versus one case in the conventional group had 0 effective phacoemulsification time (P < 0.0001). Femtosecond laser-assisted cataract surgery appears to be as safe as conventional cataract surgery in the short term and results in significantly lower effective phacoemulsification time. Although it may allow for greater efficiency and decreased postoperative complications, further research is needed into long-term safety aspects such as corneal endothelial cell loss.

Descemet Stripping Endothelial Keratoplasty

To determine the outcomes and complication rates achieved by a novice cornea surgeon when performing Descemet stripping automated endothelial keratoplasty (DSAEK) while precisely following a previously described forceps insertion technique. Prospective, noncomparative interventional case series including 100 eyes of 74 patients with endothelial decompensation. An institutional review board approved, prospective, DSAEK series was initiated. Cases included all initial patients with endothelial failure operated on by a single surgeon after his cornea fellowship training. The surgeon strictly adhered to a previously published 5-mm incision, folded forceps graft insertion technique. Patients were followed at 1 day, 1 week, and 1, 3, and 6 months. Postoperative complications (including graft dislocation, primary graft failure, and pupillary block), best spectacle-corrected visual acuity (BSCVA) and specular microscopy of central endothelial cell density at 6 months postoperatively were the main outcome measures. One hundred consecutive eyes were enrolled in the study, and 100% follow-up at 6 months was achieved. Postoperative complications included 2 graft dislocations (2%), and both grafts were attached successfully and cleared; 2 episodes of cystoid macular edema (2%) occurred, and 1 eye (1%) developed areas of anterior iris synechiae to the graft. There were no pupillary block episodes or primary graft failures. In eyes without comorbidity (n=57), the mean BSCVA improved from 20/48 preoperation to 20/29 at 6 months after operation (P<0.001). No eyes lost vision. Mean central endothelial cell density decreased from 2769 cells per square millimeter preoperatively to 2308 cells per square millimeter postoperatively at 6 months. This represented a mean cell loss of 16%. This study demonstrates that with meticulous attention to a standardized forceps insertion technique, excellent outcomes with low rates of complications, improved BSCVA, and low endothelial cell loss can be achieved with DSAEK surgery.

In reply: advantage of Parker Flex-tip Tube® in endotracheal intubation using AirwayScope® videolaryngoscope

To the Editor: Difficult tube insertion due to impingement of the straight reinforced tube in combination with the PentaxAWS (AWS) has been well recognized [1], as the Intlock blade is designed for a curved, not for the straight, tube. Dr. Kinoshita introduced their work that the insertion of the straight reinforced tube can be facilitated when the AWS blade tip is inserted into the vallecula (Macintoshtype approach) [2]. Although we did reported the successful intubation with the AWS by the Macintosh approach after the blade tip failed to lift the epiglottis [3], we are not aiming to introduce the solution after failed tube insertion in our human study, as the title shows [4]. We simply proposed that the AWS can be used with either the blade inserted into the vallecula or inserted posterior to the epiglottis for laryngeal exposure with the Parker tube. Generally, when the AWS blade tip was inserted posterior to the epiglottis, standard curved-tube insertion was easily performed by maneuvering the blade tip direction to adjust the target symbol on the vocal cords seen in the monitor. Therefore, we think the incidence of difficult tube advancement for the curved tube is very low. The impossibility of lifting the epiglottis by the blade tip is also rare in the Japanese population, and our single case [3] was only one of 2,000 cases in our hospital. Recently, Cavus proposed ‘‘the straight-blade technique’’ for the curved videolaryngoscope and that direct elevation of the epiglottis (Miller-type approach) can improve the view and increase the chance of successful intubation [5]. Our report proposed the AWS can be used not only with the Miller-type approach but also with the Macintosh-type approach for laryngeal exposure during intubation when combined with the Parker tube. We also reported that both Miller and Macintosh approaches can be effectively used for nasotracheal intubation with the AWS [6]. These ‘‘tips’’ can enhance the usefulness of the AWS in the clinical setting.

Modified single‐operator method for double‐balloon endoscopy

Applications of double-balloon endoscopy (DBE) have expanded widely to areas beyond small-intestine endoscopy. Two endoscopists are required for standard insertion, but it is preferable to have DBE carried out by one endoscopist to optimize control of the procedure and because of human resources issues. We previously reported on the Single-Operator Method, but here we describe newly modified insertion techniques that facilitate and enhance the performance of DBE by a single endoscopist. Our new technique consists of Hooking Technique, Outside Support, Grasp Scope and Overtube, Continuous Overtube Infusion and Double-Overtube Method. These new techniques make it easier to carry out the Single-Operator Method.

1551 Improving Safety of Vascular Catheter Insertion in High-Risk Newborns through Standardized Teaching

BackgroundUmbilical and percutaneous central catheter placement in high-risk newborns are common NICU procedures with high complication rates, particularly when inserter experience varies. We developed, implemented and evaluated a standardized catheter...

Seed migration after transperineal interstitial prostate brachytherapy with I-125 free seeds: analysis of its incidence and risk factors

The purpose of this study was to evaluate the incidence and predictors of seed migration after transperineal interstitial prostate brachytherapy. From March 2007 to March 2011, 121 patients with stage T1-T2 prostate cancer underwent transperineal interstitial prostate brachytherapy. Pre-planning was performed 3 weeks prior to implantation, and the implants were inserted using the standard parallel needle insertion technique. All patients underwent a series of radiographs [chest radiography, kidney-ureter-bladder (KUB) radiography, and a CT scan] to assess whether seed migration had occurred on postoperative days 1 and 30, and 12 months. Seed migration occurred in 31 (25.6 %) of 121 patients. A total of 51 of 7,883 (0.65 %) implanted seeds migrated. Migration was detected on postoperative day 1 in 16 patients, day 30 in 13 patients and at 12 months in 4 patients (migration occurred at different times in 2 patients). The migrated seeds were found in the lungs, pelvis, heart, mediastinum, kidney, inguinal canal, liver and sacrum. The number of needles was a statistically significant factor in seed migration. The seeds migrated to many organs. No decrease in the dose administered to the prostate or adverse effects associated with seed migration were noted.

A randomized controlled trial comparing the AccuVein AV300 device to standard insertion technique for intravenous cannulation of anesthetized children

To evaluate the efficacy of the AccuVein AV300 device in improving the first-time success rate of intravenous cannulation of anesthetized pediatric patients. The AccuVein AV300 device was developed to assist venepuncture and intravenous cannulation by enhancing the visibility of superficial veins. It uses infrared light to highlight hemoglobin so that blood vessels are darkly delineated against a red background. Patients were randomized to cannulation with the AccuVein AV300 device or standard insertion by experienced pediatric anesthesiologists. An observer recorded the number of skin punctures and cannulation attempts required, and the time between tourniquet application and successful cannulation or four skin punctures, whichever came first. There were 146 patients with a median age of 4.6 years (range, 0.18-17.1 years), 46.6% were male, 80.8% were light skin colored, and 15.7% were younger than 2 years. The first-attempt success rates were 75% (95% CI, 63.8-84.2%) using AV300 and 73% (95% CI, 61.9-81.9%) using the standard method (P = 0.85). Patients with dark or medium skin color were 0.38 times less likely to have a successful first attempt than patients with light skin color. The difference between the two treatment groups in number of skin punctures and the time to insertion was not significant. Although the AV300 was easy to use and improved visualization of the veins, we found no evidence that it was superior to the standard method of intravenous cannulation in unselected pediatric patients under anesthesia.

PMO-203 Direct gastric puncture and gastropexy (Freka® Pexact) insertion technique for percutaneous endoscopic gastrostomy reduces peristomal infection rates compared with standard pull-through insertion in patients with head and neck cancer

IntroductionPatients with head and neck cancer often have a percutaneous endoscopic gastrostomy (PEG) inserted to provide nutritional support while undergoing treatment. The standard pull-through PEG technique is associated with a...

Postoperative sore throat with 0.05% betamethasone gel and 2% lignocaine jelly used as a lubricant for ProSeal LMA (PLMA) insertion

Postoperative sore throat (POST) is a minor complication after general anaesthesia. Many agents have been used as lubricant to reduce the incidence of POST with variable efficacy. We conducted a study to compare the incidence of POST with 0.05% betamethasone gel and 2% lignocaine jelly as a lubricant for PLMA insertion in patients undergoing general anaesthesia.Sixty subjects were divided randomly into two groups. Patients in Group I (n = 30) had 2.5 ml of 0.05% of betamethasone gel while the Group II had 2.5 ml of 2% lignocaine jelly applied on the cuff of PLMA. After standard induction and insertion of PLMA cuff inflated to 60 cm of H2O and was maintained at the same throughout the surgery. In PACU, patients were inquired about sore throat at immediate and 24 h post operative period.POST was not observed in any of the patients of Group I. In group II 33% of the patients had 1st degree and 10% had 2nd degree of sore-throat in immediate post-operative period. After 24 h 16% patients had 1st degree sore-throat and 3% patients had 2nd degree of sore-throat in Group II patients. We conclude that lubricating cuff of PLMA with 0.05% of betamethasone gel is effective in reducing the incidence of POST.