Jeffrey Clymer - Academia.edu (original) (raw)

Papers by Jeffrey Clymer

Medical Devices : Evidence and Research, Nov 30, 2023

BMC Surgery, Jun 29, 2023

Background For thirty years, the Harmonic scalpel has been used for precise dissection, sealing a... more Background For thirty years, the Harmonic scalpel has been used for precise dissection, sealing and transection. There are numerous meta-analyses on individual surgical procedures with Harmonic, but no overarching review covering all the areas. This umbrella review seeks to summarize the clinical results from the use of Harmonic across surgical fields and broadly quantify its effects on patient outcomes. Methods MEDLINE, EMBASE, and Cochrane Databases were searched for meta-analyses (MAs) of randomized controlled trials (RCTs) comparing Harmonic devices to conventional techniques or advanced bipolar (ABP) devices. For each procedure type, the most comprehensive MAs were evaluated. RCTs not already analysed in a MA were also included. Operating time, length of stay, intraoperative blood loss, drainage volume, pain, and overall complications were evaluated, and the methodological quality and certainty of evidence were assessed. Results Twenty-four systematic literature reviews were identified on colectomy, hemorrhoidectomy, gastrectomy, mastectomy, flap harvesting, cholecystectomy, thyroidectomy, tonsillectomy, and neck dissection. There were also 83 RCTs included. In every MA evaluated, Harmonic devices were associated with either statistically significant or numerical improvements in every outcome compared with conventional techniques; most MAs reported a reduction in operating time of ≥ 25 min. Harmonic versus ABP device MAs in colectomy and thyroidectomy showed no significant differences in outcomes. Conclusion Across surgical procedures, Harmonic devices demonstrated improved patient outcomes for operating time, length of stay, intraoperative bleeding, drainage volume, pain, and overall complications compared to conventional techniques. Additional studies are required to assess differences between Harmonic and ABP devices.

American Journal of Respiratory and Critical Care Medicine, Nov 1, 2008

Rationale: Human rhinovirus infections cause colds and trigger exacerbations of lower airway dise... more Rationale: Human rhinovirus infections cause colds and trigger exacerbations of lower airway diseases. Objectives: To define changes in gene expression profiles during in vivo rhinovirus infections. Methods: Nasal epithelial scrapings were obtained before and during experimental rhinovirus infection, and gene expression was evaluated by microarray. Naturally acquired rhinovirus infections, cultured human epithelial cells, and short interfering RNA knockdown were used to further evaluate the role of viperin in rhinovirus infections. Measurements and Main Results: Symptom scores and viral titers were measured in subjects inoculated with rhinovirus or sham control, and changes in gene expression were assessed 8 and 48 hours after inoculation. Real-time reverse transcription-polymerase chain reaction for viperin and rhinoviruses was used in naturally acquired infections, and viperin mRNA levels and viral titers were measured in cultured cells. Rhinovirus-induced changes in gene expression were not observed 8 hours after viral infection, but 11,887 gene transcripts were significantly altered in scrapings obtained 2 days postinoculation. Major groups of up-regulated genes included chemokines, signaling molecules, interferon-responsive genes, and antivirals. Viperin expression was further examined and also was increased in naturally acquired rhinovirus infections, as well as in cultured human epithelial cells infected with intact, but not replication-deficient, rhinovirus. Knockdown of viperin with short interfering RNA increased rhinovirus replication in infected epithelial cells. Conclusions: Rhinovirus infection significantly alters the expression of many genes associated with the immune response, including chemokines and antivirals. The data obtained provide insights into the host response to rhinovirus infection and identify potential novel targets for further evaluation.

World journal of surgery and surgical research, Mar 12, 2021

Background: In colorectal procedures, including Low Anterior Resection (LAR), surgeons have found... more Background: In colorectal procedures, including Low Anterior Resection (LAR), surgeons have found it beneficial to use a stapler designed to provide access in the deep pelvis such as the CONTOUR® Curved Cutter Stapler (CCS). A new version of this stapler, the ECHELON CONTOUR® Curved Cutter Stapler (ECCS) has been developed, featuring Gripping Surface Technology (GST) and Three-Dimensional (3D) staples. This study was undertaken to evaluate the ECCS in comparison to the previous version and another commercially-available stapler. Methods: ECCS was compared to CCS for post-compression tissue trauma, both visually and via histological analysis, and post-stapling tissue healing response at 7-and 21-days post-surgery. ECCS was compared to the ENDO GIA Stapler (GIA) for leak onset pressure along the staple line. Results: ECCS exhibited significantly less gross visible tissue trauma following compression than the predicate device (p<0.001). Histological examination indicated similar tissue trauma and tissue healing response for ECCS and CCS. In leak onset pressure testing, ECCS provided a 30.8% higher mean pressure than GIA (p=0.002), and a 55% lower leak rate at 30 mmHg (p=0.011). Conclusion: To gain the benefits of hybrid laparoscopic colorectal techniques, the narrow head design of the CCS is particularly useful in accessing the deep pelvis. The new ECCS incorporates GST for enhanced tissue handling without any negative effect on tissue trauma or healing response. Additionally, ECCS uses 3D stapling technology which provides significantly stronger sealing. Together these technical advances make ECHELON CONTOUR® Curved Cutter Stapler the new standard in colorectal procedures.

World journal of surgery and surgical research, Oct 18, 2021

Background: The introduction of the Ethicon Echelon Circular Powered Stapler (ECP) has elevated t... more Background: The introduction of the Ethicon Echelon Circular Powered Stapler (ECP) has elevated the creation of anastomoses to a new level of precision. The improvement in tissue apposition has been documented both preclinically and more recently in clinical studies. However, there has not been a direct comparison between the ECP, which has adjustable height staples, with the EEA Circular Stapler with Tri-Staple Technology (TRS). This study was undertaken to determine whether the advantages of ECP previously observed in comparison to fixed single height staples are also present when compared to a device with fixed graduated height staples. Methods: In preclinical models, compression force on tissue, leak pressure at the staple line, tissue perfusion in the region of the staple line, and distal tip movement of the device during firing were determined for ECP and TRS. Results: ECP displayed a 38% reduction in compressive forces on tissue (p<0.001) and more evenly distributed compression forces within the staple line than TRS. ECP exhibited a 24% higher mean leak pressure (p=0.006) and 48% fewer leaks at the staple line (p=0.019). ECP showed significantly better perfusion between the inner two rows of staples (p<0.001) and throughout the entire stapled region (p<0.010). ECP had markedly less distal tip movement during firing, with less than half the movement of TRS. Conclusion: In the current study, ECP demonstrated higher leak pressures and had less distal tip movement during firing. The advantages observed for ECP previously vs. fixed single height staples have been confirmed in comparison to fixed graduated height staples in preclinical testing. These advantages may be responsible for the improved outcomes observed clinically for the Echelon Circular Powered Stapler.

With the emergence and spread of Coronavirus Disease 2019 (COVID-19), surgical care of patients h... more With the emergence and spread of Coronavirus Disease 2019 (COVID-19), surgical care of patients has been disrupted for surgeons across the world. Recently several surgical societies are raising concerns about using ultrasonic devices during laparoscopic surgery due to questions regarding a proposed risk of viral transmission of COVID-19. In this review, we will provide an overview of COVID-19’s transmission, evaluate available evidence on surgical smoke production and possible risk of viral contamination and discuss the optimization of ultrasonic device use during the ongoing COVID-19 global pandemic.

Value in Health, 2019

Objectives: Patients with unresectable stage III NSCLC are typically treated with CRT, followed b... more Objectives: Patients with unresectable stage III NSCLC are typically treated with CRT, followed by active surveillance and best standard-of-care. Prognosis is poor, with over 89% of patients progressing to metastatic disease. Various consolidation therapies have been tested but have limited efficacy. Durvalumab is the only approved consolidation treatment for patients whose disease has not progressed following concurrent platinum-based CRT. As overall survival (OS) and updated progressionfree survival (PFS) data was recently published from the PACIFIC trial, we evaluated the comparative efficacy of consolidation therapy after CRT. Methods: We systematically searched MEDLINE®, Cochrane and Embase databases for phase III randomized controlled trials assessing NSCLC patients who received overlapping CRT, with and without subsequent consolidation treatment. Trials with PFS or OS data were incorporated into a fixed-effects, proportional hazards Bayesian NMA. Studies with sequential CRT weren't included in this analysis. Results: We screened 5,140 records, identifying 4 trials which provided consolidation therapy after CRT. Durvalumab demonstrated statistically significant superiority for OS relative to standard-of-care (HR 0.68 [95% credible interval (CrI):0.55-0.87]), docetaxel (HR 0.61 [95% CrI:0.40-0.93]) and paclitaxel (HR 0.42, [95% CrI:0.26-0.69]) administered as consolidation therapy. Favorable OS outcomes for durvalumab relative to vinorelbine + cisplatin (HR: 0.70 [95% CrI:0.47-1.06]) weren't statistically significant. Bayesian posterior probability of superiority for durvalumab was estimated to be 95.1% relative to vinorelbine + cisplatin, 98.9% relative to docetaxel and 100% relative to paclitaxel. Similar to previously reported PFS results, durvalumab remains significantly superior relative to all treatments for PFS: standard-of-care (HR 0.54, [95% CrI:0.44-0.67]), vinorelbine + cisplatin (HR 0.60 [95% CrI:0.41-0.87]), docetaxel (HR 0.53 [95% CrI:0.36-0.81]) and paclitaxel (HR 0.35 [95% CrI:0.21-0.53]). Conclusions: In this NMA, durvalumab was the most favorable treatment for improving OS and PFS relative to no consolidation, or other assessed consolidation therapies. In contrast, consolidation paclitaxel was the least favorable of all assessed therapies.

Value in Health, 2015

A51 Objectives: A recent Premier study reported that despite hemostat use, uncontrolled bleeding ... more A51 Objectives: A recent Premier study reported that despite hemostat use, uncontrolled bleeding is prevalent across surgery types (32%-68%). Drawbacks of current hemostats include limitations with efficacy on first attempt and sub-optimal easeof-use; thus, better hemostats are needed. A study was conducted to estimate the cost impact of a novel fibrin sealant patch (EVARREST™) versus standard of care (SoC) in soft tissue and hepatic surgical bleeding. MethOds: An economic model quantified 30-day cost impact of EVARREST from a U.S. hospital perspective. Key resources, from four trials, included quantity of initial treatment, re-treatment, operating time, hospitalization, transfusion risk, amount transfused, and ventilator utilization. SoC was composed of Surgicel (88% to 100% in soft tissue, 34% to 65% in hepatic tissue) and conventional methods (e.g., manual compression, thrombin). Transplant patients were excluded from analyses. The surgical analysis included resources clinically related to the significant hemostasis benefit of EVARREST vs. control (i.e., initial and re-treatment, operating time, transfusion). A hospital analysis included all resources collected. Published data on U.S. costs were applied to resource use. Sensitivity analyses were conducted on several variables including number of EVARREST products used. Results: The surgical base-case analysis predicted that EVARREST was cost saving vs.

Value in Health, 2013

A495 treated. The savings mainly resulted from shorter operating time (13 Minutes) and decreased ... more A495 treated. The savings mainly resulted from shorter operating time (13 Minutes) and decreased hospital stay (0.7 days). ConClusions: Although the instrument cost is higher for the ultrasonic device, the total procedural cost is lower compared to electrosurgery. Utilization of the Harmonic® ultrasonic device in laparoscopic cholecystectomy can lead to substantial cost savings for US hospitals. PGI16 MortalIty and MedIcal costs assocIated wIth lIver-related dIseases aMonG PatIents wIth hePatItIs c vIrus(hcv) InfectIon In taIwan

Journal of Surgery, 2021

Background: Monopolar electrosurgery, one of the most widely used techniques in surgery, requires... more Background: Monopolar electrosurgery, one of the most widely used techniques in surgery, requires two electrodes: a working electrode and a return electrode. Commonly, adhesive or "sticky" pads that attach directly to the patient are used as return electrodes. Acting as electrolytic conductors, adhesive pads are highly effective, but require some effort to apply and remove, and if improperly placed or partially detached may lead to high electrical current density and the potential for pad site burns. Alternatively, a capacitive return electrode, such as the Mega Soft pad, may be used that works on the same principle as a two-plate capacitor. Objective: This article details the technology underlying capacitive electrodes, reviews the scientific literature to-date, and provides recommendations on how to best use the Mega Soft pad. Results: No direct contact is required between the pad and patient, and the return electrode is designed so that current density is limited regardless of pad placement, reducing the risk of pad site burn. Although the technology is now mature, having been in the field for over 20 years, best practices for optimal performance from capacitive return electrodes are still not widespread, and misunderstandings persist regarding use of capacitive electrodes with contact monitoring systems and implantable electronic devices. Conclusion: With proper training, capacitive return electrodes may be substituted for conventional adhesive pads with the benefits of easier application and reduced risk of pad site burns.

Medical Devices: Evidence and Research

Background: Modern surgical staplers should provide precise placement and transection, especially... more Background: Modern surgical staplers should provide precise placement and transection, especially in tight spaces and on thick tissue. Ideally, a stapler would move to accommodate variations in the tissue and anatomy instead of having to move the tissue around to fit the stapler. This study was undertaken to evaluate the performance characteristics of the new Echelon 3000 Stapler (ECH3). Use of the ECH3 was compared to another marketed stapler, including tests for access, seal strength, staple formation in thick tissue, and end effector stability. Methods: Pelvic anatomy measurements were used to construct a virtual model of a Low Anterior Resection (LAR). Monte Carlo simulations were performed on the staplers to compare the probability of completing a transection with one or two firings. Using water infusion of stapled porcine ileum, pressure at first leak and percentage of leaks at critical pressures were measured. Rate of malformed staples was measured in thick tissue. End effector stability while firing and under moderate pressure were compared between staplers. After use, surgeons were surveyed on the functionality of the device. Results: ECH3 had a markedly higher probability of completing an LAR transection in one or two firings than the comparator stapler. Median initial leak pressure of stapled ileum was significantly higher, and rate of leaks was lower at 40 and 50 mmHg. ECH3 had fewer malformed staples for both 3.3-and 4.0-mm thick tissue. The end effector exhibited less angular movement during firing, and less deflection under a moderate load. Surgeons agreed the ECH3 provided precise placement and easy one-handed operation. Conclusion: The Echelon 3000 Stapler demonstrated improved access capability, tighter seals, fewer malformed staples, and greater end effector stability. These advantages were recognized by surgeons who evaluated the use of the device preclinically.

Surgical Technology Online, 2022

Background: Since its adoption as a surgical technique over a half-century ago, stapling has cont... more Background: Since its adoption as a surgical technique over a half-century ago, stapling has continually undergone improvements, both in the devices used and in our understanding of tissue mechanics. To best design and use stapling devices, it is beneficial to have an intimate knowledge of the response of tissue to compression and stapling dynamics. This paper provides the relevant background in the field of biomechanics, and in particular addresses the viscoelastic behavior of soft tissues under compression. Biomechanics of Stapling: The change in shape of a solid, or strain, is related to the load applied, or stress. Biological tissues are known to have non-linear relationships between stress and strain, and generally the relationships are anisotropic (dependent upon direction). Further complicating matters, there is typically a time-dependency to the relationship for compression and recovery, resulting in viscoelastic behavior. Hence both the amount and rate of compressive force ...

Forest plot of random effects meta-analysis results for EHM (P = 0.659). Forest plot of secondary... more Forest plot of random effects meta-analysis results for EHM (P = 0.659). Forest plot of secondary outcome data. Abbreviations: EHM, extrahepatic metastasis (PDF 1517 kb)

Forest plot of random effects meta-analysis results for 5-year OS (P = 0.01). Forest plot of seco... more Forest plot of random effects meta-analysis results for 5-year OS (P = 0.01). Forest plot of secondary outcome data. Abbreviations: OS, overall survival (PDF 2537 kb)

Forest plot of random effects meta-analysis results for 3-year OS (P = 0.03). Forest plot of seco... more Forest plot of random effects meta-analysis results for 3-year OS (P = 0.03). Forest plot of secondary outcome data. Abbreviations: OS, overall survival (PDF 3075 kb)

Forest plot of random effects meta-analysis results for 1-year OS (P = 0.409). Forest plot of sec... more Forest plot of random effects meta-analysis results for 1-year OS (P = 0.409). Forest plot of secondary outcome data. Abbreviations: OS, overall survival (PDF 3082 kb)

Methodological quality assessment of observational studies using the NOS scale. Table of Newcastl... more Methodological quality assessment of observational studies using the NOS scale. Table of Newcastleâ Ottawa scale assessments of the included observational studies. (XLSX 10 kb)

Study treatment selection criteria and resectability. Table describing the selection criteria use... more Study treatment selection criteria and resectability. Table describing the selection criteria used to assign patients to different treatments and descriptions of whether MWA patients were resectable. (DOCX 31 kb)

Search Strategies. List of search terms and results used to obtain the studies reviewed for inclu... more Search Strategies. List of search terms and results used to obtain the studies reviewed for inclusion in the meta-analysis. (DOCX 52 kb)