Troubleshooting the bypass: intraoperative management of initially failed anastomosis in direct cerebral revascularization surgery

OBJECTIVE

Direct cerebral revascularization is considered as one of the most technically challenging operations in neurosurgery. Technical errors are often not identified during the case, but only after the recirculation stage, making management crucial at that time of the procedure. In this study, the authors sought to describe troubleshooting of the technical errors encountered in initially failed bypass cases.

METHODS

A retrospective analysis describing a single-surgeon, single-institution experience between 2014 and 2021 was performed, based on operative reports and videos, including a 30-day follow-up period. Initially failed bypass was defined if the bypass was not patent or had a significant leak after recirculation, irrespective of the final result.

RESULTS

One hundred thirty-eight bypass cases were reviewed for complex aneurysms (n = 49), moyamoya disease (n = 59), and atherosclerosis (n = 30). Fifty-one initially failed anastomoses were identified; 43 of these were the result of a technical error. Etiologies of these failed anastomoses included a clot (n = 14), vessel kinking (n = 4), spasm (n = 5), suture-related cause (n = 5), inappropriate donor or recipient (n = 3), or lack of demand (n = 8). A major leak was attributed to an uncoagulated side branch (n = 4), vessel injury due to suture/clip placement (n = 1), or inadequate suture line coverage (n = 7). Thirty-seven (86%) of 43 cases were troubleshot successfully, as salvage maneuvers included papaverine vessel massage, donor repositioning, re-anastomosis for occlusion in select cases, local hemostatic agents, and suturing or coagulating side branches in a leak. Thirty-day follow-up revealed similar rates of patency between successfully troubleshot patients (35/37) and the rest of the cases (80/87, p = 0.6).

CONCLUSIONS

Three major patterns of a noncompatible bypass were found: a major leak, an acute occlusion, or a delayed occlusion. Based on the authors' experience, salvage strategies proved successful, showing an eventual high patency rate. The authors suggest a gradual, structured algorithm to address this stage in surgery that may contribute specifically to cerebrovascular neurosurgeons at the beginning of their careers.

Optical Genome Mapping for Oncology Applications

Optical genome mapping (OGM) is a next-generation cytogenomic technology that has the potential to replace standard-of-care technologies used in the genetic workup of various malignancies. The ability to detect various classes of structural variations that include copy number variations, deletions, duplications, balanced and unbalanced events (insertions, inversions, and translocation) and complex genomic rearrangements in a single assay and analysis demonstrates the utility of the technology in tumor research and clinical application. Herein, we provide the methodological details for performing OGM and pre- and post-analytical quality control (QC) checks and describe critical steps that should be performed with caution, probable causes for specific QC failures, and potential method modifications that could be implemented as part of troubleshooting. The protocol description and troubleshooting guide should help new and current users of the technology to improve or troubleshoot the problems (if any) in their workflow. © 2023 Wiley Periodicals LLC. Basic Protocol: Optical genome mapping.

Strategies for capillary electrophoresis: Method development and validation for pharmaceutical and biological applications-Updated and completely revised edition

This review is in support of the development of selective, precise, fast, and validated capillary electrophoresis (CE) methods. It follows up a similar article from 1998, Wätzig H, Degenhardt M, Kunkel A. "Strategies for capillary electrophoresis: method development and validation for pharmaceutical and biological applications," pointing out which fundamentals are still valid and at the same time showing the enormous achievements in the last 25 years. The structures of both reviews are widely similar, in order to facilitate their simultaneous use. Focusing on pharmaceutical and biological applications, the successful use of CE is now demonstrated by more than 600 carefully selected references. Many of those are recent reviews; therefore, a significant overview about the field is provided. There are extra sections about sample pretreatment related to CE and microchip CE, and a completely revised section about method development for protein analytes and biomolecules in general. The general strategies for method development are summed up with regard to selectivity, efficiency, precision, analysis time, limit of detection, sample pretreatment requirements, and validation.

A Vexing Problem of Air Trapping in the Trima Accel During Plateletpheresis Procedure: Reflecting Our Experience in Troubleshooting

Troubleshooting for any fault of apheresis equipment or kit is hardly addressed. Here, we report a unique problem of air trapping in a kit at two different positions leading to failure of the plateletpheresis procedure. Two plateletpheresis procedures were aborted due to "Access pressure low", though the needle position was absolutely perfect. In the third event, platelet yield was not increasing even after 30 minutes from the time of initiation. It was completed after stopping the centrifuge pump which could have displaced the air bubble from the collection port. The root cause for these events was analyzed in consultation with the apheresis technical expert and "air block" was found to be the cause. Air block can also result in a "low access pressure" alarm despite improper phlebotomy being the common cause. Perfect kit loading, checking of tubing defects prior to loading, and comparative analysis of troubleshooting to have adequate knowledge are essential tools for the smooth functioning of apheresis.

Success rates, challenges and troubleshooting of left bundle branch area pacing as a cardiac resynchronization therapy for treating patients with heart failure

Cardiac resynchronization therapy (CRT) is an important treatment of heart failure patients with reduced left ventricular ejection fraction (LVEF) and asynchrony of cardiac electromechanical activity. Left bundle branch area pacing (LBBaP) is a novel physiological pacing modality that appears to be an effective method for CRT. LBBaP has several advantages over the traditional biventricular-CRT (BiV-CRT), including a low and stable pacing capture threshold, a high success rate of implantation, a short learning curve, and high economic feasibility. However, LBBaP is not suitable for all heart failure patients needing a CRT and the success rates of LBBaP in heart failure patients is lower because of myocardial fibrosis, non-specific intraventricular conduction disturbance (IVCD), enlargement of the right atrium or right ventricle, etc. In this literature review, we summarize the success rates, challenges, and troubleshooting of LBBaP in heart failure patients needing a CRT.

Single-Port Robotic Surgery: General Principles and Troubleshooting

The da Vinci single-port (SP) system (Intuitive Surgical, Sunnyvale, CA) is the newest robotic platform released and approved for use in the urologist's armimentarium. This article (and complementary video) aims to summarize the most common problems that have been encountered at the University of Illinois at Chicago when using the SP system. Moreover, solutions to these issues will be presented.

Various innovative roles for 3-Fr microcatheters in pancreaticobiliary endoscopy

With the development of newer devices and technical innovations, pancreaticobiliary endoscopy is expanding to assume more advanced therapeutic roles. As with other devices, slimmed-down "3-Fr microcatheters" are considered to be opening new windows toward entirely new therapeutic techniques for various purposes. Our practical experience with a total of 34 consecutive patients in whom 3-Fr microcatheters were applied during pancreaticobiliary endoscopic procedures clarified the potential roles of this instrument in pancreaticobiliary endoscopy. The major benefits of 3-Fr microcatheters involve their slimness and flexibility. Applications of 3-Fr microcatheters could be categorized into three groups according to the characteristics of usage: (1) utilization as a cannulation catheter for peroral digital cholangioscopy (n = 15); (2) selective advancement through deep flexures or severely stenotic ducts (n = 11); or (3) two-devices-in-one-channel technique (n = 8). The microcatheter worked successfully for cannulation of cholangioscopy in all but one case (14/15, 93.3%). For selective advancement, the microcatheter worked for troubleshooting in 9 of 11 cases (81.8%). With the two-devices-in-one-channel technique, the microcatheter proved satisfactory in all cases (8/8, 100%). In total, the microcatheter was successfully maneuvered in 31 of 34 cases (91.1%), following the failure of procedures using conventional endoscopic techniques. In terms of adverse events, cystic duct injury was only observed in two cases (5.8%), who recovered under conservative observation, because its slimness could minimize the damage. We believe that 3-Fr microcatheters offer effective and safe salvage troubleshooting during various endoscopic pancreaticobiliary procedures that face troublesome situations with conventional strategies.

OverStitch Sx Endoscopic suturing system in minimally invasive endoscopic procedures: overview of its safety and efficacy and comparison to oversticthTM

INTRODUCTION

OverStitch endoscopic suturing enables advanced closure by tissue approximation via endoscopically placed sutures with the ability to customize suture patterns. Newer OverStitch generation also known as OverStitch Sx overcame the limitation of the previous generation and is compatible with 20 single channel scopes over four platforms with greater maneuverability and visibility.

AREAS COVERED

In this article we will focus on the differences between three generations of OverStitch. In addition, we will review existing literature on the efficacy of OverStitch in the management of full thickness defect closure, fistula and leaks repair, stent fixation, and bariatric surgeries along with its complications and limitations.

EXPERT OPINION

Assembling overstitch takes less than five minutes and the correct sequence of system assembly is the key for a successful procedure. Transition from the second-generation OverStitch to OverStitch Sx may require three to five cases for learning curve.

The Influence of Electrode Configuration Changes on the Sensory and Motor Response During (Re)Programming in Sacral Neuromodulation

OBJECTIVES

This study aimed to assess the neurophysiological basis behind troubleshooting in sacral neuromodulation (SNM). Close follow-up of SNM patients with program parameter optimization has proven to be paramount by restoring clinical efficacy and avoiding surgical revision.

MATERIALS AND METHODS

A total of 34 successful SNM patients (28 overactive bladder wet, six nonobstructive urinary retention) with an implantable pulse generator were included. All possible bipolar and monopolar electrode settings were tested at sensory threshold (ST) to evaluate sensory (mapped on a perineal grid with 1 cm² coordinates) and motor (peak-to-peak amplitude and latency of muscle action potential) responses of the pelvic floor. Pelvic floor muscle electromyography was recorded using a multiple array probe, placed intravaginally. Parametric tests were used for paired data: repeated-measures ANOVA or t-test. A nonparametric test was used for paired data: Friedman ANOVA or Wilcoxon signed rank (WSR) test; p < 0.05 was considered statistically significant. If significant, ANOVA was followed by Dunn-Bonferroni post hoc analysis.

RESULTS

Monopolar configurations showed significantly lower STs-1.38 ± 0.73 V vs 1.76 ± 0.89 V (paired t-test: p < 0.0001)-and presented with significantly higher peak-to-peak amplitudes-115.67 ± 79.03 μV vs 90.77 ± 80.55 μV (WSR: p = 0.005)-than bipolar configurations. When polarity was swapped, configurations with the cathode distal to the anode showed significantly lower STs, 1.73 ± 0.91 V vs 1.85 ± 0.87 V (paired t-test: p = 0.003), and mean peak-to-peak amplitudes, 81.32 ± 72.82 μV vs 100.21 ± 90.22 μV (WSR: p = 0.0001). Cathodal changes resulted in more changes in sensory responses than anodal changes (χ² test: p = 0.044). In cathodal changes only, peak-to-peak amplitudes were significantly higher when the distance between electrodes was maximally spread (WSR: p = 0.046).

CONCLUSIONS

From a neurophysiological point of view, monopolar configurations stimulated more motor nerve fibers at lower STs, therefore providing more therapeutic efficiency. Swapping polarity or changing the position of the cathode led to different sensory and motor responses, serving as potential reprogramming options.

Tips and tricks for successfully culturing and adapting human induced pluripotent stem cells

Reprogramming somatic cells toward pluripotency became possible over a decade ago. Since then, induced pluripotent stem cells (iPSCs) have served as a versatile and powerful tool not only for basic research but also with the long-term goal of using them in human cell transplantation after differentiation. Nonetheless, downstream applications are frequently blurred by the difficulties that researchers have to face when working with iPSCs, such as trouble with clonal selection, in vitro culture and cryopreservation, adaptation to feeder-free conditions, or expansion of the cells. Therefore, in this article we aim to provide other researchers with practical and detailed information to successfully culture and adapt iPSCs. Specifically, we (1) describe the most common problems when in-vitro culturing iPSCs onto feeder cells as well as its possible troubleshooting, and (2) compare different matrices and culture media for adapting the iPSCs to feeder-free conditions. We believe that the troubleshooting and recommendations provided in this article can be of use to other researchers working with iPSCs and who may be experiencing similar issues, hopefully enhancing the appeal of this promising cell source to be used for biomedical investigations, such as tissue engineering or regenerative medicine applications.

Troubleshooting Programming of Conduction System Pacing

Conduction system pacing (CSP) comprises His bundle pacing and left bundle branch area pacing and is rapidly gaining widespread adoption. Effective CSP not only depends on successful system implantation but also on proper device programming. Current implantable impulse generators are not specifically designed for CSP. Either single chamber, dual chamber or CRT devices can be used for CSP depending on the underlying heart rhythm (sinus rhythm or permanent atrial arrhythmia) and the aim of pacing. Different programming issues may arise depending on the device configuration. This article aims to provide an update on practical considerations for His bundle and left bundle branch area pacing programming and follow-up.

[1.5 T Nuclear Magnetic Resonance Imaging System Failure Treatment and Rectification Summary]

Quench of magnetic resonance imaging system refers to the process that the superconducting condition inside the magnet is destroyed due to some reason. The large current stored in the coil is quickly converted into heat at the place where the resistance is formed, and a large amount of liquid helium in the magnet is evaporated. If it happens, it will cause huge loss to the user. We introduce the real cases of 1.5 T magnetic resonance imaging system's quench fault, maintenance treatment and management improvement, which can be used for reference by various medical institutions, so as to better strengthen the operation and maintenance management of magnetic resonance imaging system, so as to avoid the occurrence of out of tolerance fault, and do a good job in the guarantee work after the out of tolerance fault.

Reprogramming Sacral Neuromodulation for Sub-Optimal Outcomes: Evidence and Recommendations for Clinical Practice

Objectives

In some patients treated for urinary or fecal incontinence with sacral neuromodulation (SNM) persistence of symptoms, a reduction in efficacy or adverse effects of stimulation can occur. In such situations, further programming of the SNM device can help resolve problems. Infrequently hardware failure is detected. This article aims to provide practical guidance to solve sub‐optimal outcomes (troubleshooting) occurring in the course of SNM therapy.

Materials and Methods

A systematic literature review was performed. Collective clinical experience from an expert multidisciplinary group was used to form opinion where evidence was lacking.

Results

Circumstances in which reprogramming is required are described. Actions to undertake include changes of electrode configuration, stimulation amplitude, pulse frequency, and pulse width. Guidance in case of loss of efficacy and adverse effects of stimulation, developed by a group of European experts, is presented. In addition, various hardware failure scenarios and their management are described.

Conclusions

Reprogramming aims to further improve patient symptoms or ensure a comfortable delivery of the therapy. Initial changes of electrode configuration and adjustment of stimulation parameters can be performed at home to avoid unnecessary hospital visits. A logical and stepwise approach to reprogramming can improve the outcome of therapy and restore patient satisfaction.

IONM Troubleshooting in Spinal Procedures

A useful reference for practitioners of neuromonitoring that explains how to anticipate, avoid, and properly attend to technical problems that may arise while providing intraoperative neuromonitoring (IONM) in spinal procedures.

Solutions for Shared Resource Lab Remote Quality Control and Instrument Troubleshooting during a Pandemic

The COVID-19 pandemic has dramatically affected shared resource lab (SRL) staff in-person availability at institutions globally. This article discusses the challenges of ensuring reliable instrument performance and quality data output while facility staff and external service provider on-site presence is severely limited. Solutions revolve around the adoption of remote monitoring and troubleshooting platforms, provision of self-service troubleshooting resources specific to facility instruments and workflows, development of an assistance contact policy, and ensuring efficiency of limited in-person staff time. These solutions employ software and hardware tools that are already in use or readily available in the SRL community, such as remote instrument access tools, video hosting and conferencing platforms, and ISAC shared resources. © 2020 International Society for Advancement of Cytometry.

A Comprehensive Review on Pharmaceutical Film Coating: Past, Present, and Future

Pharmaceutical film coating is considered a key part in the production of solid pharmaceutical dosage forms since it gives superior organoleptic properties products. In addition, it can improve the physical and chemical stability of dosage forms, and modify the release characteristics of the drug. Several troubleshooting problems such as twinning mottling, chipping, etc., may arise during or after or even during the shelf life of the film coated dosage forms. These troubleshooting problems may be due to tablet core faults, coating formulation faults and/or coating process faults. These problems must be overcome to avoid unnecessary product problems. Film coating as well as other parts of the pharmaceutical technology is subjecting to continuous innovation. The innovation may be at different levels including pharmaceutical excipients, processes, software, guidelines and equipment. In fact, of particular note is the growing interest in process analytical technology, quality by design, continuous coating processing and the inclusion of new ready for use coating formulations. In this review, we tried to explore and discuss the status of pharmaceutical film coating, the challenges that face this manufacturing process and the latest technological advances in this important manufacturing process.

[Versa HD Volume-modulated Accelerator High Voltage Circuit Fault Maintenance]

This paper introduces a fast repair methods of Versa HD volume-modulated accelerator's high voltage circuit fault:the key points test method. To identify five key points:①Enter maintenance mode to check for AFC deviation; ② The magnetron waveform MI and PFN waveform PFN V are detected on the maintenance terminal board; ③ Detect thyratron waveform; ④ Check the supply voltage of thyratron; ⑤ HT PSU 600 V DC test 600 V normal or not. The waveform or voltage is also measured to efficiently narrow the fault range to find out the cause of the fault, quickly remove the fault.

Surgical management of adverse events associated with deep brain stimulation: A single-center experience

Objectives:

Deep brain stimulation is widely used to treat movement disorders and selected neuropsychiatric disorders. Despite the fact, the surgical methods vary among centers. In this study, we aimed to evaluate our own surgical complications and how we performed surgical troubleshooting.

Methods:

A retrospective chart review was performed to evaluate the clinical data of patients who underwent deep brain stimulation surgery and deep brain stimulation–related procedures at our center between October 2014 and September 2019. We reviewed surgical complications and how surgical troubleshooting was performed, regardless of where the patient underwent the initial surgery.

Results:

A total of 92 deep brain stimulation lead implantation and 43 implantable pulse generator replacement procedures were performed. Among the 92 lead implantation procedures, there were two intracranial lead replacement surgeries and one deep brain stimulation lead implantation into the globus pallidus to add to existing deep brain stimulation leads in the bilateral subthalamic nuclei. Wound revision for superficial infection of the implantable pulse generator site was performed in four patients. There was neither intracerebral hemorrhage nor severe hardware infection in our series of procedures. An adaptor (extension cable) replacement was performed due to lead fracture resulting from a head trauma in two cases.

Conclusion:

We report our experience of surgical management of adverse events associated with deep brain stimulation therapy with clinical vignettes. Deep brain stimulation surgery is a safe and effective procedure when performed by a trained neurosurgeon. It is important for clinicians to be aware that there are troubles that are potentially manageable with optimal surgical treatment.

A Practical Approach to Investigating Cross-Contaminants in the Anatomical Pathology Laboratory

Tissue contaminants in anatomical pathology are not uncommon. While issues related to the presence of extraneous tissue on glass slides are often easily resolved, this is not always the case and several factors may contribute to diagnostic difficulty. Because of this, familiarity with the different steps involved in handling specimens in the anatomical pathology laboratory is essential when troubleshooting possible cross-contaminants. Most commonly, the specimen constituting the source of cross-contamination is handled before the actual contaminated case; however, this is not always so. In this article, we review the steps involved in processing pathology specimens as they pertain to cross-contamination; share an approach covering how to troubleshoot and prevent tissue contaminants in a systematic and practical manner; present some examples from our own experiences; and compare our experience to what is reported in the literature. The information included in this article will be of use to all members of the anatomical pathology team including medical laboratory technologists, laboratory managers and supervisors, pathologist assistants, trainees in pathology, and pathologists.

Multiphoton intravital microscopy in small animals: motion artefact challenges and technical solutions

Since its invention 29 years ago, two‐photon laser‐scanning microscopy has evolved from a promising imaging technique, to an established widely available imaging modality used throughout the biomedical research community. The establishment of two‐photon microscopy as the preferred method for imaging fluorescently labelled cells and structures in living animals can be attributed to the biophysical mechanism by which the generation of fluorescence is accomplished. The use of powerful lasers capable of delivering infrared light pulses within femtosecond intervals, facilitates the nonlinear excitation of fluorescent molecules only at the focal plane and determines by objective lens position. This offers numerous benefits for studies of biological samples at high spatial and temporal resolutions with limited photo‐damage and superior tissue penetration. Indeed, these attributes have established two‐photon microscopy as the ideal method for live‐animal imaging in several areas of biology and have led to a whole new field of study dedicated to imaging biological phenomena in intact tissues and living organisms. However, despite its appealing features, two‐photon intravital microscopy is inherently limited by tissue motion from heartbeat, respiratory cycles, peristalsis, muscle/vascular tone and physiological functions that change tissue geometry. Because these movements impede temporal and spatial resolution, they must be properly addressed to harness the full potential of two‐photon intravital microscopy and enable accurate data analysis and interpretation. In addition, the sources and features of these motion artefacts are varied, sometimes unpredictable and unique to specific organs and multiple complex strategies have previously been devised to address them. This review will discuss these motion artefacts requirement and technical solutions for their correction and after intravital two‐photon microscopy.

Algorithm-based troubleshooting to manage bleeding during thoracoscopic anatomic pulmonary resection

Background

Few studies have reported on the effects of intraoperative complications, such as vessel injury, during thoracoscopic anatomic pulmonary resection. We evaluated intraoperative vessel injury and assessed troubleshooting methods for thoracoscopic anatomic pulmonary resection.

Methods

A total of 378 patients underwent thoracoscopic anatomic pulmonary resection between April 2012 and March 2018, 40 of whom were identified as having an intraoperative vessel injury. In our department, we treat significant bleeding based on the algorithm shown in Figure 1. We analyzed the injured vessels and hemostatic procedures employed and compared perioperative outcomes in patients with (n=40) or without (n=338) a vessel injury. Additionally, we examined the data on a year-by-year basis from April 2012, and perioperative results were compared in each year.

Results

The vessel injured was a branch of the pulmonary artery in 22 cases (55%). Hemostasis was achieved by applying a thrombostatic sealant in 26 cases (65%). Although patients without a vessel injury had a shorter operation time, less intraoperative blood loss, and shorter duration of chest tube drainage, no significant differences in the length of postoperative hospitalization or morbidity were observed. The occurrence rate of significant intraoperative bleeding in the last year measured was similar to that in the first year measured.

Conclusions

Thoracoscopic anatomic pulmonary resection is feasible and safe if the surgeon performs appropriate hemostasis, although vascular hazards might be inherent during thoracoscopic anatomic pulmonary resection, regardless of the surgeon's experience.

High incidence of diaphragmatic myopotential oversensing by a specific implantable cardioverter defibrillator

INTRODUCTION

Diaphragmatic myopotential oversensing (dMPO) by implantable cardioverter defibrillators (ICDs) is thought to be a rare condition that can be misdiagnosed as lead failure and lead to unnecessary lead replacement. We observed several cases of dMPO in patients with Sorin/LivaNova ICDs (MicroPort Sci.). We sought to systematically assess the incidence of dMPO in patients with Sorin/LivaNova ICDs.

METHODS AND RESULTS

A predefined number of 100 consecutive patients with Sorin/LivaNova ICDs were prospectively included in the device clinic of our center. Stored arrhythmia episodes were checked for spontaneous dMPO. In addition, we performed provocation maneuvers by Valsalva. At least one episode of spontaneous or provoked dMPO was seen in 12 (12%) of the 100 patients included in the study (86% males, median age: 66 years). Nine of 89 patients (10%) with true bipolar and 3 of 11 patients (27%) with integrated bipolar sensing configuration were affected. Spontaneous dMPO was observed in 7 of 58 patients (12%) with sensitivity programmed to 0.4 mV and in 2 of 42 patients (5%) with sensitivity programmed to 0.6 mV (not significant). In three patients, dMPO could be provoked with no spontaneous episodes recorded. In two nonpacemaker-dependent patients with a CRT-D, ventricular pacing was temporarily inhibited. No antitachycardia therapy was triggered by dMPO in any patient.

CONCLUSIONS

DMPO is frequent in patients with Sorin/LivaNova ICDs, especially with sensitivity programmed to 0.4 mV. It also frequently occurs with true bipolar sensing configuration. DMPO should not be misinterpreted as lead failure to avoid unnecessary lead replacement.

DCD and DBD lung transplantation optimized by ex vivo perfusion: What to do when the pump fails

BACKGROUND

Ex vivo perfusion is a safe and feasible method of assessing and using high-risk donor organs.

AIM

We describe a case of successfully ex vivo treated and transplanted human lung allografts.

METHODS

Donor human lungs were assessed using ex vivo, our trouble shooting protocol allowed safe recovery.

RESULTS

We successfully implanted our ex vivo treated organs.

An improved method for quantitative ChIP studies of nuclear receptor function

Chromatin immunoprecipitation (ChIP) is a valuable tool for the endocrine researcher, providing a means to measure the recruitment of hormone-activated nuclear receptors, for example. However, the technique can be challenging to perform and has multiple experimental steps, risking introduction of error at each. The data produced can be challenging to interpret; several different methods are commonly used for normalising data and thus comparing between conditions. Absolute, sensitive quantification of protein-bound DNA is important for correct interpretation of the data. In addition, such quantification can help the investigator in troubleshooting experiments. Here, we outline a ChIP strategy combining droplet digital PCR for accurate quantification with an internal spike-in control for normalisation. This combination strengthens the reliability of ChIP data and allows the operator to optimise their protocol with greater confidence.

An indissoluble knot: An unexpected troubleshooting during Micra implantation

Micra is a transcatheter leadless pacing system delivered percutaneously through femoral vein access into the right ventricle. We are going to describe an initially standard procedure, with an unexpected troubleshooting at the end: the impossibility to release the device and retract the delivery due to a knot in the tether.

Troubleshooting for F-18 Fluorocholine Synthesis: An Institutional Experience

Choline is a natural substrate for phospholipid synthesis. F-18 labeled fluorocholine nowadays is routinely used for imaging brain tumors, parathyroid adenoma, and prostate cancer. It is synthesized through nucleophilic substitution reaction using dibromomethane and N, N-dimethylaminoethanol as primary and secondary precursors, respectively. However, sometimes, failures are encountered in F-18 fluorocholine production. Few problems and troubleshooting during synthesis are discussed here.

Evaluation of CyberKnife® Fiducial Tracking Limitations to Assist Targeting Accuracy: A Phantom Study with Fiducial Displacement

Introduction 

The underlying assumptions of the CyberKnife® (Accuray, Sunnyvale, CA, US) fiducial tracking system are: i) fiducial positions are accurately detected; ii) inter-fiducial geometry remains consistent (rigid); iii) inter-fiducial geometric array changes are detected and either accommodated with corrections or treatment is interrupted. However: i) soft-tissue targets are deformable & fiducial migration is possible; ii) the accuracy of the tracking system has not previously been examined with fiducial displacement; iii) treatment interruptions may occur due to inter-fiducial geometric changes, but there is little information available to assist subsequent troubleshooting. The purpose of this study was to emulate a clinical target defined with a two, three, or four-fiducial array where one fiducial is displaced to mimic a target deformation or fiducial migration scenario. The objectives: evaluate the fiducial positioning accuracy, array interpretation, & corresponding corrections of the CyberKnife system, with the aim of assisting troubleshooting following fiducial displacement.

Methods

A novel solid-water phantom was constructed with three fixed fiducials (F1,F2,F3) & one moveable fiducial (F4), arranged as if placed to track an imaginary clinical target. Using either two fiducials (F1,F4), different combinations of three fiducials (F1,F2,F4; F1,F3,F4; F2,F3,F4) or four fiducials (F1,F2,F3,F4), repeat experiments were conducted where F4 was displaced inferiorly at 2-mm intervals from 0-16 mm. Data were acquired at each position of F4, including rigid body errors (RBE), fiducial x, y, & z coordinate displacements, six degrees of freedom (DOF) corrections, & robot center-of-mass (COM) translation corrections.

Results

Maximum positioning difference (mean±SD) between the reference and live x, y, & z coordinates for the three fixed fiducials was 0.08±0.30 mm, confirming good accuracy for fixed fiducial registration. For two fiducials (F1,F4), F4 registration was accurate to 14-mm displacement and the F4 x-axis coordinate change was 2.0±0.12 mm with each 2 mm inferior displacement validating the phantom for tracking evaluation. RBE was >5 mm (system threshold) at 6-14 mm F4 displacement: however, F1 was misidentified as the RBE main contributor. Further, F1/F4 false-lock occurred at 16 mm F4 displacement with corresponding RBE <3 mm & COM corrections >13 mm. For combinations of three fiducials, F4 registration was accurate to 10-mm displacement. RBE was >5 mm at 6-16 mm F4 displacement: however, F4 false-lock occurred at 12-16 mm with RBE 5-6 mm. For four fiducials, F4 registration was accurate to 4 mm displacement: however, F4 false-lock occurred at 6-16 mm displacement with concerning RBE <2 & <5 at 6 & 8-mm F4 displacement, respectively. False-locks were easily identified in the phantom but frequently uncorrectable.

Conclusions

Results indicate fiducial positioning accuracy and system output following fiducial displacement depends on the number of fiducials correlated, displacement distance, and clinical thresholds applied. Displacements ≤4 mm were accurately located, but some displacements 6-16 mm were misrepresented, either by erroneous main contributor (two-fiducial array only) or by false-locks and misleading RBE, which underestimated displacement. Operator vigilance and implementation of our practical guidelines based on the study findings may help reduce targeting error and assist troubleshooting in clinical situations.

Troubleshooting complicated hilar anatomy via prophylactically clamping the pulmonary artery: three videos demonstrating three techniques

Complicated hilar anatomy (i.e., tumor invasion, lymphadenopathy, calcification, carbonization, and dense inflammatory adhesions) is technically challenging and often leads to catastrophic intraoperative complications and conversion to open thoracotomy during video-assisted thoracic surgery (VATS) lobectomy. The technique of prophylactically clamping the pulmonary artery (PA) has been reported to be effective in troubleshooting complicated hilar anatomy. However, there are no records on details regarding techniques to treat different hilar complication situations. In this paper, we will introduce three techniques, namely suture ligation, endo-stapler angioplasty, and suture angioplasty, for dealing with different kinds of complicated hili during VATS lobectomy through three video demonstrations.

Technical problems during laparoscopy: a systematic method of troubleshooting for surgeons

Background:

Laparoscopic surgery has progressed rapidly since the early 1990s. For some surgical operations, it has become the standard of care to the extent where open surgery is sometimes looked down upon by some surgical colleagues as well as by patients.

Current status:

Despite this widespread adoption and acceptance, many surgeons struggle to understand how the laparoscopy stacks work despite having the skills to perform the operation. Most hospitals rely on operating theatre assistants to troubleshoot in the event of problems. This could be potentially unsafe for patients if laparoscopic vision or pneumoperitoneum is lost at a critical point of the operation.

Discussion:

There are a number of approaches that have been published for troubleshooting laparoscopy stack. We explore and discuss some of them along with their advantages and disadvantages and how they relate to our methodology and approach. As a product of the discussion, we suggest a systematic way forward to troubleshooting laparoscopic tower equipment problems.

Conclusion:

The technical knowledge of surgeons and trainees varies widely in the area of laparoscopy-related troubleshooting. This systematic, practical algorithm would help and guide all surgeons to adopt a uniform approach, thereby improving patient safety.

Serous-lined, stapled pouch wall plication: initial results of a simple and quick novel continence mechanism in troubleshooting secondary to continent cutaneous urinary diversion

OBJECTIVES

To report a novel and straightforward technique of a secondary continent outlet for continent cutaneous urinary diversion (CCUD) reservoirs without the need for further bowel resection, reducing operating time and length of hospitalization.

PATIENTS AND METHODS

From 2015 to 2017, six patients with unreconstructable, incontinent outlets (out of a total pool of 595 patients with CCUD) have undergone the technique described in the present paper at our department. The technique relies on the Mitrofanoff principle, using a stapled full-thickness pouch wall plication, which creates a flap-valve continence mechanism.

RESULTS

All patients enjoyed full continence with ease of clean intermittent catheterization (CIC) in the postoperative period and on follow-up to a mean (range) of 12.4 (7-18) months. No major complications were encountered in any patient and the average capacity of the reservoirs was not compromised by the procedure (540 mL preoperatively vs 500 mL in further follow-up).

CONCLUSION

In revisional surgery for secondary CCUD incontinence, especially if the patient has already lost a significant amount of bowel or has previously undergone radiation therapy, the technique described here represents a safe and effective alternative to restore continence.

Fifteen-minute consultation on the healthy child: breast feeding

Despite extensive evidence about the benefits of breast feeding for both infants and mothers, breastfeeding rates in the UK remain low. Most infants presenting with feeding issues are otherwise well but are often over diagnosed with clinical conditions such as maternal milk insufficiency, cow's milk intolerance or reflux. With simple advice and troubleshooting common problems, all child health professionals can support mothers to establish and continue breast feeding exclusively for longer.

Anaesthetic consideration in patients with cardiac implantable electronic devices scheduled for surgery

With advances in cardiology and cardiothoracic surgery, several newer implantable cardiac devices have become common in the surgical population. Multichamber pacemakers, implanted cardiac defibrillators and ventricular assist devices are frequent in current day practice. Many of the newer implantable cardiac electronic devices are targeted at managing heart failure. While managing such patients for non-cardiac surgeries, specific issues related to equipment characteristics and troubleshooting should be a priority for the anaesthesiologists. There is a possibility of malfunction of the devices resulting in catastrophic outcomes. Therefore, it is imperative to understand the pathophysiology, device characteristics and troubleshooting before embarking on anaesthetising patients with implantable cardiac electronic devices.

Polymerase chain reaction: basic protocol plus troubleshooting and optimization strategies

In the biological sciences there have been technological advances that catapult the discipline into golden ages of discovery. For example, the field of microbiology was transformed with the advent of Anton van Leeuwenhoek's microscope, which allowed scientists to visualize prokaryotes for the first time. The development of the polymerase chain reaction (PCR) is one of those innovations that changed the course of molecular science with its impact spanning countless subdisciplines in biology. The theoretical process was outlined by Keppe and coworkers in 1971; however, it was another 14 years until the complete PCR procedure was described and experimentally applied by Kary Mullis while at Cetus Corporation in 1985. Automation and refinement of this technique progressed with the introduction of a thermal stable DNA polymerase from the bacterium Thermus aquaticus, consequently the name Taq DNA polymerase. PCR is a powerful amplification technique that can generate an ample supply of a specific segment of DNA (i.e., an amplicon) from only a small amount of starting material (i.e., DNA template or target sequence). While straightforward and generally trouble-free, there are pitfalls that complicate the reaction producing spurious results. When PCR fails it can lead to many non-specific DNA products of varying sizes that appear as a ladder or smear of bands on agarose gels. Sometimes no products form at all. Another potential problem occurs when mutations are unintentionally introduced in the amplicons, resulting in a heterogeneous population of PCR products. PCR failures can become frustrating unless patience and careful troubleshooting are employed to sort out and solve the problem(s). This protocol outlines the basic principles of PCR, provides a methodology that will result in amplification of most target sequences, and presents strategies for optimizing a reaction. By following this PCR guide, students should be able to: • Set up reactions and thermal cycling conditions for a conventional PCR experiment • Understand the function of various reaction components and their overall effect on a PCR experiment • Design and optimize a PCR experiment for any DNA template • Troubleshoot failed PCR experiments.

Multisensor system for isotemporal measurements to assess indoor climatic conditions in poultry farms

The rearing of poultry for meat production (broilers) is an agricultural food industry with high relevance to the economy and development of some countries. Periodic episodes of extreme climatic conditions during the summer season can cause high mortality among birds, resulting in economic losses. In this context, ventilation systems within poultry houses play a critical role to ensure appropriate indoor climatic conditions. The objective of this study was to develop a multisensor system to evaluate the design of the ventilation system in broiler houses. A measurement system equipped with three types of sensors: air velocity, temperature and differential pressure was designed and built. The system consisted in a laptop, a data acquisition card, a multiplexor module and a set of 24 air temperature, 24 air velocity and two differential pressure sensors. The system was able to acquire up to a maximum of 128 signals simultaneously at 5 second intervals. The multisensor system was calibrated under laboratory conditions and it was then tested in field tests. Field tests were conducted in a commercial broiler farm under four different pressure and ventilation scenarios in two sections within the building. The calibration curves obtained under laboratory conditions showed similar regression coefficients among temperature, air velocity and pressure sensors and a high goodness fit (R(2) = 0.99) with the reference. Under field test conditions, the multisensor system showed a high number of input signals from different locations with minimum internal delay in acquiring signals. The variation among air velocity sensors was not significant. The developed multisensor system was able to integrate calibrated sensors of temperature, air velocity and differential pressure and operated successfully under different conditions in a mechanically-ventilated broiler farm. This system can be used to obtain quasi-instantaneous fields of the air velocity and temperature, as well as differential pressure maps to assess the design and functioning of ventilation system and as a verification and validation (V&V) system of Computational Fluid Dynamics (CFD) simulations in poultry farms.

Troubleshooting adult ECMO

The following scenarios explore some of the common problems encountered during extracorporeal membrane oxygenation (ECMO) in adults. In each scenario, the circuit is comprised of a centrifugal pump and a polymethylpentene oxygenator.