Pulmonary embolism (PE) is a leading cause of cardiovascular morbidity and mortality. Systemic thrombolysis is recommended for high-risk PE, but risk of major bleeding limits its use despite its efficacy. While mechanical thrombectomy (MT) has emerged as an alternative reperfusion strategy, real-world safety data remains limited. The objective of this single-center retrospective observational cohort study was to characterize the safety profile and procedural complications of MT. Methods Adult patients with intermediate-risk and high-risk PE who underwent MT at a quaternary academic medical center between January 1, 2017, and December 31, 2024, were included. Demographic, clinical, laboratory, imaging, procedural, outcome, and mortality data were collected. Major adverse events and bleeding were defined according to established criteria. Results From a total of 103 screened patients, 65 were included. Of these, 22 (34%) were classified as high-risk and 43 (66%) as intermediate-risk. Baseline demographics were similar between groups. High-risk patients demonstrated greater clinical disease severity, with higher mean Pulmonary Embolism Severity Index (PESI) scores (188.5 vs 122.4). Clinical deterioration prior to MT occurred in 35% of intermediate-risk patients. Extracorporeal membrane oxygenation (ECMO) consultation rate (32% vs 7%), peri-procedural ECMO use (18% vs 2.3%), major bleeding (27% vs 4.7%), and in-hospital mortality (36% vs 11.6%) were higher in the high-risk group. Thrombus removal was achieved in 77% and 88% of high- and intermediate-risk patients, respectively. High-risk patients had longer ICU (mean 4 vs 1.3 days) and hospital stays (mean 21.5 vs 6.4 days), higher thirty-day mortality (36% vs 14%), and lower 90-day survival (59% vs 79%). Conclusions MT achieved high rates of thrombus removal in both groups. In this retrospective cohort, high-risk patients had greater baseline clinical severity and was associated with higher bleeding rates, greater resource utilization, including ECMO consultation and peri-procedural use, prolonged ICU and hospital stays, as well as increased mortality.
A bioadhesive pacing lead for atraumatic cardiac monitoring and stimulation in rodent and porcine models
Current clinically used electronic implants, including cardiac pacing leads for epicardial monitoring and stimulation of the heart, rely on surgical suturing or direct insertion of electrodes to the heart tissue. These approaches can cause tissue trauma during the implantation and retrieval of the pacing leads, with the potential for bleeding, tissue damage, and device failure. Here, we report a bioadhesive pacing lead that can directly interface with cardiac tissue through physical and covalent interactions to support minimally invasive adhesive implantation and gentle on-demand removal of the device with a detachment solution. We developed 3D-printable bioadhesive materials for customized fabrication of the device by graft-polymerizing polyacrylic acid on hydrophilic polyurethane and mixing with poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to obtain electrical conductivity. The bioadhesive construct exhibited mechanical properties similar to cardiac tissue and strong tissue adhesion, supporting stable electrical interfacing. Infusion of a detachment solution to cleave physical and covalent cross-links between the adhesive interface and the tissue allowed retrieval of the bioadhesive pacing leads in rat and porcine models without apparent tissue damage. Continuous and reliable cardiac monitoring and pacing of rodent and porcine hearts were demonstrated for 2 weeks with consistent capture threshold and sensing amplitude, in contrast to a commercially available alternative. Pacing and continuous telemetric monitoring were achieved in a porcine model. These findings may offer a promising platform for adhesive bioelectronic devices for cardiac monitoring and treatment.
Preserving the Membrane Lung: An Ongoing ECMO Challenge
Extracorporeal membrane oxygenation (ECMO) poses unique thrombotic and hemorrhagic risks, and the optimal anticoagulant choice is unknown. We systematically searched Ovid EBM Reviews, Ovid Embase, Ovid Medline, Scopus, and Web of Science Core Collection for randomized-, crossover-, retrospective cohort-, or parallel-designed clinical studies of adult patients receiving ECMO that compared heparin recipients with bivalirudin recipients. Meta-analysis was performed with random-effects models. The ROBINS-I tool was used to assess the risk of bias. Six retrospective observational studies met the inclusion criteria for the qualitative summary. Five studies were suitable for meta-analysis. Those who received heparin were more likely to experience circuit-related thrombosis (odds ratio [OR] 2.05, 95% confidence interval [CI] 1.25–3.37, p = 0.005, I 2 = 0%) and die (OR 1.62, 95% CI 1.19–2.21, p = 0.002, I 2 = 0%) compared with those who received bivalirudin. There were no differences in major bleeding events between heparin and bivalirudin recipients (OR 1.83, 95% CI 0.55–6.09, p = 0.33, I 2 = 82.7%). In retrospective settings compared with heparin anticoagulation, bivalirudin was associated with less circuit-related thrombotic events and greater survival in adults supported on ECMO, without contributing to more bleeding complications. Prospective controlled studies comparing heparin and bivalirudin in adult ECMO patients are warranted to corroborate these findings.
An off-the-shelf bioadhesive patch for sutureless repair of gastrointestinal defects
Surgical sealing and repair of injured and resected gastrointestinal (GI) organs are critical requirements for successful treatment and tissue healing. Despite being the standard of care, hand-sewn closure of GI defects using sutures faces limitations and challenges. In this work, we introduce an off-the-shelf bioadhesive GI patch capable of atraumatic, rapid, robust, and sutureless repair of GI defects. The GI patch integrates a nonadhesive top layer and a dry, bioadhesive bottom layer, resulting in a thin, flexible, transparent, and ready-to-use patch with tissue-matching mechanical properties. The rapid, robust, and sutureless sealing capability of the GI patch is systematically characterized using ex vivo porcine GI organ models. In vitro and in vivo rat models are used to evaluate the biocompatibility and degradability of the GI patch in comparison to commercially available tissue adhesives (Coseal and Histoacryl). To validate the GI patch’s efficacy, we demonstrate successful sutureless in vivo sealing and healing of GI defects in rat colon, stomach, and small intestine as well as in porcine colon injury models. The proposed GI patch provides a promising alternative to suture for repair of GI defects and offers potential clinical opportunities for the repair of other organs.
MIT Emergency-Vent: An Automated Resuscitator Bag for the COVID-19 Crisis
2021 43rd Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC) | December 9, 2021 | Volume: No volume available | Issue: No issue available | Pages: 4998-5004
AbstractFor decades, bioadhesive materials have garnered great attention due to their potential to replace sutures and staples for sealing tissues during minimally invasive surgical procedures. However, the complexities of delivering bioadhesives through narrow spaces and achieving strong adhesion in fluid‐rich physiological environments continue to present substantial limitations to the surgical translation of existing sealants. In this work, a new strategy for minimally invasive tissue sealing based on a multilayer bioadhesive patch, which is designed to repel body fluids, to form fast, pressure‐triggered adhesion with wet tissues, and to resist biofouling and inflammation is introduced. The multifunctional patch is realized by a synergistic combination of three distinct functional layers: i) a microtextured bioadhesive layer, ii) a dynamic, blood‐repellent hydrophobic fluid layer, and iii) an antifouling zwitterionic nonadhesive layer. The patch is capable of forming robust adhesion to tissue surfaces in the presence of blood, and exhibits superior resistance to bacterial adhesion, fibrinogen adsorption, and in vivo fibrous capsule formation. By adopting origami‐based fabrication strategies, it is demonstrated that the patch can be readily integrated with a variety of minimally invasive end effectors to provide facile tissue sealing in ex vivo porcine models, offering new opportunities for minimally invasive tissue sealing in diverse clinical scenarios.
Ultrathin and Robust Hydrogel Coatings on Cardiovascular Medical Devices to Mitigate Thromboembolic and Infectious Complications
AbstractThromboembolic and infectious complications stemming from the use of cardiovascular medical devices are still common and result in significant morbidity and mortality. There is no strategy to date that effectively addresses both challenges at the same time. Various surface modification strategies (e.g., silver, heparin, and liquid‐impregnated surfaces) are proposed yet each has several limitations and shortcomings. Here, it is shown that the incorporation of an ultrathin and mechanically robust hydrogel layer reduces bacterial adhesion to medical‐grade tubing by 95%. It is additionally demonstrated, through a combination of in vitro and in vivo tests, that the hydrogel layer significantly reduces the formation and adhesion of blood clots to the tubing without affecting the blood's intrinsic clotting ability. The adhesion of clots to the tubing walls is reduced by over 90% (in vitro model), which results in an ≈60% increase in the device occlusion time (time before closure due to clot formation) in an in vivo porcine model. The advantageous properties of this passive coating make it a promising surface material candidate for medical devices interfacing with blood.
Instant tough bioadhesive with triggerable benign detachment
Significance Owing to potential advantages including ease of use, airtight or watertight sealing, and minimal tissue damage, bioadhesives have been intensively studied and developed as an alternative to sutures and staples to close wounds, achieve hemostasis, and attach and immobilize implantable devices. However, existing bioadhesives have limitations including slow adhesion formation, weak bonding, low biocompatibility, poor mechanical match with tissues, and/or lack of triggerable benign detachment. In this work, we report a bioadhesive capable of instant tough adhesion and triggerable benign detachment that can potentially address all the above-mentioned limitations. The current work not only develops a bioadhesive with superior performances but also advances the understanding of wet adhesion.