1
|
Padilla C, Zakowski M, Einav S, Weiniger C, Landau R, Chestnut D. The time is now: addressing the need for training in maternal critical care medicine. Int J Obstet Anesth 2022; 50:103544. [DOI: 10.1016/j.ijoa.2022.103544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 02/18/2022] [Accepted: 03/18/2022] [Indexed: 11/25/2022]
|
2
|
Simonis FD, Einav S, Serpa Neto A, Hemmes SN, Pelosi P, Gama de Abreu M, Schultz MJ. Epidemiology, ventilation management and outcome in patients receiving intensive care after non-thoracic surgery - Insights from the LAS VEGAS study. Pulmonology 2021; 28:90-98. [PMID: 34906445 DOI: 10.1016/j.pulmoe.2021.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 10/18/2021] [Accepted: 10/26/2021] [Indexed: 10/19/2022] Open
Abstract
INTRODUCTION AND OBJECTIVES Information about epidemiology, ventilation management and outcome in postoperative intensive care unit (ICU) patients remains scarce. The objective was to test whether postoperative ventilation differs from that in the operation room. MATERIAL AND METHODS This was a substudy of the worldwide observational LAS VEGAS study, including patients undergoing non-thoracic surgeries. Of 146 study sites participating in the LAS VEGAS study, 117 (80%) sites reported on the postoperative ICU course, including ventilation and complications. The coprimary outcomes were two key elements of ventilator management, i.e., tidal volume (VT) and positive end-expiratory pressure (PEEP). Secondary outcomes included the proportion of patients receiving low VT ventilation (LTVV, defined as ventilation with a median VT < 8.0 ml/kg PBW), and the proportion of patients developing postoperative pulmonary complications (PPC), including ARDS, pneumothorax, pneumonia and need for escalation of ventilatory support, ICU and hospital length of stay, and mortality at day 28. RESULTS Of 653 patients who were admitted to the ICU after surgery, 274 (42%) patients received invasive postoperative ventilation. Median postoperative VT was 8.4 [7.3-9.8] ml/kg predicted body weight (PBW), PEEP was 5 [5-5] cm H2O, statistically significant but not meaningfully different from median intraoperative VT (8.1 [7.3-8.9] ml/kg PBW; P < 0.001) and PEEP (4 [2-5] cm H2O; P < 0.001). The proportion of patients receiving LTVV after surgery was 41%. The PPC rate was 10%. Length of stay in ICU and hospital was independent of development of a PPC, but hospital mortality was higher in patients who developed a PPC (24 versus 4%; P < 0.001). CONCLUSIONS In this observational study of patients undergoing non-thoracic surgeries, postoperative ventilation was not meaningfully different from that in the operating room. Like in the operating room, there is room for improved use of LTVV. Development of PPC is associated with mortality.
Collapse
Affiliation(s)
- F D Simonis
- Department of Intensive Care, Amsterdam UMC, location Academic Medical Center, Amsterdam, the Netherlands.
| | - S Einav
- General Intensive Care Unit, Shaare Zedek Medical Center and Hebrew University Faculty of Medicine, Jerusalem, Israel
| | - A Serpa Neto
- Department of Intensive Care, Amsterdam UMC, location Academic Medical Center, Amsterdam, the Netherlands; Department of Critical Care Medicine, Australian and New Zealand Intensive Care Research Centre (ANZIC-RC), Monash University, Melbourne, Australia
| | - S N Hemmes
- Department of Anesthesiology, Amsterdam UMC, location Academic Medical Center, Amsterdam, the Netherlands
| | - P Pelosi
- Department of Surgical Sciences and Integrated Diagnostics, IRCCS San Martino IST, University of Genoa, Genoa, Italy
| | - M Gama de Abreu
- Department of Anesthesiology and Intensive Care, University Hospital Carl Gustav Carus, Dresden, Germany
| | - M J Schultz
- Department of Intensive Care, Amsterdam UMC, location Academic Medical Center, Amsterdam, the Netherlands; Mahidol Oxford Tropical Medicine Research Unit (MORU), Mahidol University, Bangkok, Thailand; Nuffield Department of Medicine, University of Oxford, Oxford, UK
| |
Collapse
|
3
|
Duclos G, Granier S, Hili A, Blanc J, Einav S, Leone. M, Zieleskiewicz L. Performance of non-invasive stroke volume variation during passive leg raise as a predictor of hypotension following induction of spinal anesthesia for elective cesarean delivery: a single cohort study. Int J Obstet Anesth 2021; 50:103251. [DOI: 10.1016/j.ijoa.2021.103251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 12/03/2021] [Accepted: 12/23/2021] [Indexed: 10/19/2022]
|
4
|
Massarwa E, Aronis Z, Eliasy R, Einav S, Haj-Ali R. Nonlinear multiscale analysis of coronary atherosclerotic vulnerable plaque artery: fluid-structural modeling with micromechanics. Biomech Model Mechanobiol 2021; 20:1889-1901. [PMID: 34191188 DOI: 10.1007/s10237-021-01483-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Accepted: 06/17/2021] [Indexed: 11/24/2022]
Abstract
A unique three-dimensional (3D) computational multiscale modeling approach is proposed to investigate the influence of presence of microcalcification particles on the stress field distribution in the thin cap layer of a coronary atherosclerotic vulnerable plaque system. A nested 3D modeling analysis framework spanning the multiscale nature of a coronary atherosclerotic vulnerable plaque is presented. At the microscale level, a micromechanical modeling approach, which is based on computational finite-element (FE) representative unit cell, is applied to obtain the homogenized nonlinear response of the calcified tissue. This equivalent response effectively allows the integration of extremely small microcalcification inclusions in a global biomechanical FE model. Next, at the macroscale level, a 3D patient-based fluid-structure interaction FE model, reconstructing a refined coronary artery geometry with calcified plaque lesion, is generated to study the mechanical behavior of such multi-component biomechanical system. It is shown that the proposed multiscale modeling approach can generate a higher resolution of stress and strain field distributions within the coronary atherosclerotic vulnerable plaque system and allow the assessment of the local concentration stress around the microcalcifications in plaque cap layers. A comparison of stress field distributions within cap layers with and without inclusion of microcalcifications is also presented.
Collapse
Affiliation(s)
- Eyass Massarwa
- Faculty of Engineering, School of Mechanical Engineering, Tel-Aviv University, Ramat Aviv 69978, Tel-Aviv, Israel
| | - Ze'ev Aronis
- Faculty of Engineering, School of Mechanical Engineering, Tel-Aviv University, Ramat Aviv 69978, Tel-Aviv, Israel
| | - Rami Eliasy
- Faculty of Engineering, School of Mechanical Engineering, Tel-Aviv University, Ramat Aviv 69978, Tel-Aviv, Israel
| | - Shmuel Einav
- Faculty of Engineering, School of Mechanical Engineering, Tel-Aviv University, Ramat Aviv 69978, Tel-Aviv, Israel
| | - Rami Haj-Ali
- Faculty of Engineering, School of Mechanical Engineering, Tel-Aviv University, Ramat Aviv 69978, Tel-Aviv, Israel.
| |
Collapse
|
5
|
Affiliation(s)
- S N Myatra
- Department of Anaesthesia, Critical Care and Pain, Tata Memorial Hospital, Homi Bhabha National Institute, Mumbai, India
| | - S Tripathy
- Department of Anaesthesia and Critical Care, AIIMS Bhubaneswar, Bhubaneswar, India
| | - S Einav
- Department of Anaesthesia and Intensive Care, Hebrew University Faculty of Medicine and General Intensive Care Unit, Shaare Zedek Medical Center, Jerusalem, Israel
| |
Collapse
|
6
|
Braz LG, Einav S, Heesen MA, Betini M, Corrente JE, Pacchioni M, Cury JB, Braz MG, Braz JRC. Association between intra-operative cardiac arrest and country Human Development Index status: a systematic review with meta-regression analysis and meta-analysis of observational studies . Anaesthesia 2021; 76:1259-1273. [PMID: 33512708 DOI: 10.1111/anae.15374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2020] [Indexed: 01/07/2023]
Abstract
Intra-operative cardiac arrests differ from most in-hospital cardiac arrests because they reflect not only the patient's condition but also the quality of surgery and anaesthesia care provided. We assessed the relationship between intra-operative cardiac arrest rates and country Human Development Index (HDI), and the changes occurring in these rates over time. We searched PubMed, EMBASE, Scopus, LILACS, Web of Science, CINAHL and SciELO from inception to 29 January 2020. For the global population, rates of intra-operative cardiac arrest and baseline ASA physical status were extracted. Intra-operative cardiac arrest rates were analysed by time, country HDI status and ASA physical status using meta-regression analysis. Proportional meta-analysis was performed to compare intra-operative cardiac arrest rates and ASA physical status in low- vs. high-HDI countries and in two time periods. Eighty-two studies from 25 countries with more than 29 million anaesthetic procedures were included. Intra-operative cardiac arrest rates were inversely correlated with country HDI (p = 0.0001); they decreased over time only in high-HDI countries (p = 0.040) and increased with increasing ASA physical status (p < 0.0001). Baseline ASA physical status did not change in high-HDI countries (p = 0.106), while it decreased over time in low-HDI countries (p = 0.040). In high-HDI countries, intra-operative cardiac arrest rates (per 10,000 anaesthetic procedures) decreased from 9.59 (95%CI 6.59-13.16) pre-1990 to 5.17 (95%CI 4.42-5.97) in 1990-2020 (p = 0.013). During the same time periods, no improvement was observed in the intra-operative cardiac arrest rates in low-HDI countries (p = 0.498). Odds ratios of intra-operative cardiac arrest rates in ASA 3-5 patients were 8.48 (95%CI 1.67-42.99) times higher in low-HDI countries than in high-HDI countries (p = 0.0098). Intra-operative cardiac arrest rates are related to country-HDI and decreased over time only in high-HDI countries. The widening gap in these rates between low- and high-HDI countries needs to be addressed globally.
Collapse
Affiliation(s)
- L G Braz
- Anaesthesia Cardiac Arrest and Mortality Study Commission, Department of Surgical Specialties and Anaesthesiology, Botucatu Medical School, Sao Paulo State University - UNESP, Botucatu, Brazil
| | - S Einav
- Shaare Zedek Medical Centre, Jerusalem, Israel.,Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - M A Heesen
- Department of Anaesthesia, Kantonsspital Baden, Baden, Switzerland
| | - M Betini
- Technical Division of Library and Documentation, Institute of Biosciences, Sao Paulo State University - UNESP, Botucatu, Brazil
| | - J E Corrente
- Department of Biostatistics, Institute of Biosciences, Sao Paulo State University - UNESP, Botucatu, Brazil
| | - M Pacchioni
- Anaesthesia Cardiac Arrest and Mortality Study Commission, Department of Surgical Specialties and Anaesthesiology, Botucatu Medical School, Sao Paulo State University - UNESP, Botucatu, Brazil
| | - J B Cury
- Anaesthesia Cardiac Arrest and Mortality Study Commission, Department of Surgical Specialties and Anaesthesiology, Botucatu Medical School, Sao Paulo State University - UNESP, Botucatu, Brazil
| | - M G Braz
- Anaesthesia Cardiac Arrest and Mortality Study Commission, Department of Surgical Specialties and Anaesthesiology, Botucatu Medical School, Sao Paulo State University - UNESP, Botucatu, Brazil
| | - J R C Braz
- Anaesthesia Cardiac Arrest and Mortality Study Commission, Department of Surgical Specialties and Anaesthesiology, Botucatu Medical School, Sao Paulo State University - UNESP, Botucatu, Brazil
| |
Collapse
|
7
|
Cortegiani A, Ippolito M, Greco M, Granone V, Protti A, Gregoretti C, Giarratano A, Einav S, Cecconi M. Rationale and evidence on the use of tocilizumab in COVID-19: a systematic review. Pulmonology 2021; 27:52-66. [PMID: 32713784 PMCID: PMC7369580 DOI: 10.1016/j.pulmoe.2020.07.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 07/07/2020] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Tocilizumab is an IL-6 receptor-blocking agent proposed for the treatment of severe COVID-19. The aim of this systematic review was to describe the rationale for the use of tocilizumab for the treatment of COVID-19 and to summarize the available evidence regarding its efficacy and safety. METHODS MEDLINE, PubMed, EMBASE, pre-print repositories (bioRxiv and medRxiv) and two trial Registries were searched for studies on the use of tocilizumab in COVID-19 or SARS-CoV-2 infection, viral pneumonia, and/or sepsis until 20th June 2020. RESULTS We identified 3 indirect pre-clinical studies and 28 clinical studies including 5776 patients with COVID-19 (13 with a comparison group, 15 single-arm). To date, no randomized trials have been published. We retrieved no studies at low risk of bias. Forty-five ongoing studies were retrieved from trial registries. CONCLUSIONS There is insufficient evidence regarding the clinical efficacy and safety of tocilizumab in patients with COVID-19. Its use should be considered experimental, requiring ethical approval and clinical trial oversight.
Collapse
Affiliation(s)
- A Cortegiani
- Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), University of Palermo. Department of Anesthesia Intensive Care and Emergency, Policlinico Paolo Giaccone, Palermo, Italy.
| | - M Ippolito
- Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), University of Palermo. Department of Anesthesia Intensive Care and Emergency, Policlinico Paolo Giaccone, Palermo, Italy.
| | - M Greco
- Department of Anesthesiology and Intensive Care, Humanitas Clinical and Research Center - IRCCS, Milan, Italy; Department of Biomedical Science, Humanitas University, Milan, Italy.
| | - V Granone
- Department of Anesthesiology and Intensive Care, Humanitas Clinical and Research Center - IRCCS, Milan, Italy; Department of Biomedical Science, Humanitas University, Milan, Italy.
| | - A Protti
- Department of Anesthesiology and Intensive Care, Humanitas Clinical and Research Center - IRCCS, Milan, Italy; Department of Biomedical Science, Humanitas University, Milan, Italy.
| | - C Gregoretti
- Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), University of Palermo. Department of Anesthesia Intensive Care and Emergency, Policlinico Paolo Giaccone, Palermo, Italy; Fondazione "Giglio", Cefalù, Italy.
| | - A Giarratano
- Department of Surgical, Oncological and Oral Science (Di.Chir.On.S.), University of Palermo. Department of Anesthesia Intensive Care and Emergency, Policlinico Paolo Giaccone, Palermo, Italy.
| | - S Einav
- IntensiveCare Unit of the Shaare Zedek Medical Medical Centre and Hebrew University Faculty of Medicine, Jerusalem, Israel.
| | - M Cecconi
- Department of Anesthesiology and Intensive Care, Humanitas Clinical and Research Center - IRCCS, Milan, Italy; Department of Biomedical Science, Humanitas University, Milan, Italy.
| |
Collapse
|
8
|
Vargas M, Servillo G, Einav S. Lopinavir/ritonavir for the treatment of SARS, MERS and COVID-19: a systematic review. Eur Rev Med Pharmacol Sci 2020; 24:8592-8605. [PMID: 32894567 DOI: 10.26355/eurrev_202008_22659] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE Lopinavir/ritonavir has been used for the treatment of Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) coronavirus infections. It has been suggested that, based on this experience, this drug should also be studied in SARS-CoV2 infection. MATERIALS AND METHODS We performed a systematic review of the literature regarding the use of lopinavir/ritonavir for the treatment of these three infections. We systematically searched the PubMed database from inception to April 30th, 2020, to identify in-vitro and animal studies and any reports of human use of lopinavir/ritonavir for the treatment of SARS, MERS and COVID-19. We also searched the Clinicatrial.gov to identify ongoing trials. RESULTS Five in-vitro studies evaluated the effect of lopinavir/ritonavir in SARS. Three additional in-vitro studies reported the EC50 of the antiviral activity of lopinavir/ritonavir in MERS. We identified no in vitro studies evaluating the effect of lopinavir/ritonavir on the novel coronavirus. Two retrospective matched-cohort studies reported the use of lopinavir/ritonavir in combination with ribavirin for SARS patients. Three case reports and one retrospective study described the use of lopinavir/ritonavir in MERS. Twenty-two papers describe the use of lopinavir/ritonavir in adult patients with COVID-19. CONCLUSIONS The existing literature does not suffice for assessing whether Lopinavir/ritonavir has any benefit in SARS, MERS or COVID-19.
Collapse
Affiliation(s)
- M Vargas
- Department of Neurosciences, Reproductive and Odontostomatological Sciences, University of Naples "Federico II", Naples, Italy.
| | | | | |
Collapse
|
9
|
Abstract
Heart valve diseases are common disorders with five million annual diagnoses being made in the United States alone. All heart valve disorders alter cardiac hemodynamic performance; therefore, treatments aim to restore normal flow. This paper reviews the state-of-the-art clinical and engineering advancements in heart valve treatments with a focus on hemodynamics. We review engineering studies and clinical literature on the experience with devices for aortic valve treatment, as well as the latest advancements in mitral valve treatments and the pulmonic and tricuspid valves on the right side of the heart. Upcoming innovations will potentially revolutionize treatment of heart valve disorders. These advancements, and more gradual enhancements in the procedural techniques and imaging modalities, could improve the quality of life of patients suffering from valvular disease who currently cannot be treated.
Collapse
Affiliation(s)
- Gil Marom
- School of Mechanical Engineering, Tel Aviv University, Tel Aviv Israel
- To whom correspondence should be addressed. E-mail:
| | - Shmuel Einav
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
10
|
Pastene B, Cassir N, Tankel J, Einav S, Fournier PE, Thomas P, Leone M. Mediastinitis in the intensive care unit patient: a narrative review. Clin Microbiol Infect 2020; 26:26-34. [DOI: 10.1016/j.cmi.2019.07.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 07/02/2019] [Accepted: 07/04/2019] [Indexed: 12/28/2022]
|
11
|
Rochwerg B, Granton D, Wang DX, Einav S, Burns KEA. High-flow nasal cannula compared with conventional oxygen therapy for acute hypoxemic respiratory failure: author's reply. Intensive Care Med 2019; 45:1171. [DOI: 10.1007/s00134-019-05658-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2019] [Indexed: 10/26/2022]
|
12
|
Abstract
Obstetric intensive care unit (ICU) admissions comprise only a small part of severe maternal morbidity. The incidence rate of both remains relatively unclear due to inconsistent definitions across publications, although this has begun to be addressed. There is a relative paucity of information regarding disease-specific survival following obstetric ICU admission, but outcomes are clearly related to the cause of admission and the quality of care. The ratio between maternal near-miss cases (many of whom are admitted to ICUs) and maternal death may provide insight into the preventability of death. Hemorrhage and pre-eclampsia constitute the leading causes of ICU admission and have relatively low mortality rates, perhaps demonstrating the impact of informed care in managing obstetric critical illness. Obstetric sepsis, heart disease and anesthesia complications should be the focus of future research. The incidence of obstetric sepsis has been increasing in the last decade, with mortality rates remaining relatively high. The incidence of obstetric heart disease is increasing and maternal complications have been attributed to fractionated care of mothers within this category. Anesthesia complications remain a predominant cause of maternal death and likely intensive care admission. Data are lacking regarding the relative proportion of cases per disease that remain treated outside the ICU; and the outcomes of various management strategies. The only study of the health status of survivors of obstetric ICU admission revealed that six months after hospital discharge, one in five women still had a poorer health-related quality of life than those of a reference age- and sex-matched cohort.
Collapse
Affiliation(s)
- S Einav
- Intensive Care Unit, Shaare Zedek Medical Center and Hebrew University School of Medicine, Jerusalem, Israel.
| | - M Leone
- Department of Anesthesiology and Intensive Care Medicine, Hôpital Nord, Assistance Publique Hôpitaux de Marseille, Aix Marseille University, Marseille, France
| |
Collapse
|
13
|
Ramirez L, Diaz L, Alshami A, Einav S, Varon J. WHO CAN PERFORM BETTER CPR? CARDIOPULMONARY RESUSCITATION ON TELEVISION MEDICAL DRAMAS: RESULTS OF THE TVMD2 STUDY. Chest 2019. [DOI: 10.1016/j.chest.2019.02.151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
|
14
|
Ramirez L, Alshami A, Einav S, Varon J. GENDER DIFFERENCES IN CARDIOPULMONARY RESUSCITATION ON TELEVISION MEDICAL DRAMAS: RESULTS OF THE TVMD2 STUDY. Chest 2019. [DOI: 10.1016/j.chest.2019.02.152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
15
|
Rochwerg B, Granton D, Wang DX, Helviz Y, Einav S, Frat JP, Mekontso-Dessap A, Schreiber A, Azoulay E, Mercat A, Demoule A, Lemiale V, Pesenti A, Riviello ED, Mauri T, Mancebo J, Brochard L, Burns K. High flow nasal cannula compared with conventional oxygen therapy for acute hypoxemic respiratory failure: a systematic review and meta-analysis. Intensive Care Med 2019; 45:563-572. [PMID: 30888444 DOI: 10.1007/s00134-019-05590-5] [Citation(s) in RCA: 138] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 02/28/2019] [Indexed: 01/08/2023]
Abstract
BACKGROUND This systematic review and meta-analysis summarizes the safety and efficacy of high flow nasal cannula (HFNC) in patients with acute hypoxemic respiratory failure. METHODS We performed a comprehensive search of MEDLINE, EMBASE, and Web of Science. We identified randomized controlled trials that compared HFNC to conventional oxygen therapy. We pooled data and report summary estimates of effect using relative risk for dichotomous outcomes and mean difference or standardized mean difference for continuous outcomes, with 95% confidence intervals. We assessed risk of bias of included studies using the Cochrane tool and certainty in pooled effect estimates using GRADE methods. RESULTS We included 9 RCTs (n = 2093 patients). We found no difference in mortality in patients treated with HFNC (relative risk [RR] 0.94, 95% confidence interval [CI] 0.67-1.31, moderate certainty) compared to conventional oxygen therapy. We found a decreased risk of requiring intubation (RR 0.85, 95% CI 0.74-0.99) or escalation of oxygen therapy (defined as crossover to HFNC in the control group, or initiation of non-invasive ventilation or invasive mechanical ventilation in either group) favouring HFNC-treated patients (RR 0.71, 95% CI 0.51-0.98), although certainty in both outcomes was low due to imprecision and issues related to risk of bias. HFNC had no effect on intensive care unit length of stay (mean difference [MD] 1.38 days more, 95% CI 0.90 days fewer to 3.66 days more, low certainty), hospital length of stay (MD 0.85 days fewer, 95% CI 2.07 days fewer to 0.37 days more, moderate certainty), patient reported comfort (SMD 0.12 lower, 95% CI 0.61 lower to 0.37 higher, very low certainty) or patient reported dyspnea (standardized mean difference [SMD] 0.16 lower, 95% CI 1.10 lower to 1.42 higher, low certainty). Complications of treatment were variably reported amongst included studies, but little harm was associated with HFNC use. CONCLUSION In patients with acute hypoxemic respiratory failure, HFNC may decrease the need for tracheal intubation without impacting mortality.
Collapse
Affiliation(s)
- B Rochwerg
- Michael G. De Groote School of Medicine, McMaster University, Hamilton, ON, Canada. .,Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada. .,Department of Medicine, Division of Critical Care, Juravinski Hospital, 711 Concession St, Hamilton, ON, L8V 1C3, Canada.
| | - D Granton
- Michael G. De Groote School of Medicine, McMaster University, Hamilton, ON, Canada
| | - D X Wang
- Schulich School of Medicine, Western University, London, ON, Canada
| | - Y Helviz
- General Intensive Care Unit, Shaare Zedek Medical Center, Jerusalem, Israel
| | - S Einav
- General Intensive Care Unit, Shaare Zedek Medical Center, Jerusalem, Israel.,Faculty of Medicine, Hebrew University, Jerusalem, Israel
| | - J P Frat
- CHU de Poitiers, Médecine Intensive Réanimation, Poitiers, France.,INSERM, CIC-1402, équipe ALIVE, Poitiers, France.,Faculté de Médecine et de Pharmacie de Poitiers, Université de Poitiers, Poitiers, France
| | - A Mekontso-Dessap
- Hôpitaux Universitaires Henri Mondor, Créteil, France.,Université Paris, Créteil, France
| | - A Schreiber
- Department of Medicine, Division of Respirology, University Health Network, Toronto, ON, Canada
| | - E Azoulay
- Hôpital Saint-Louis, Paris, France.,Center of Epidemiology and Biostatistics, Paris Diderot Sorbonne University, Paris, France
| | - A Mercat
- Département de Médecine Intensive-Réanimation, CHU d'Angers, Université d'Angers, Angers, France
| | - A Demoule
- Service de Pneumologie et Réanimation Médicale du Département R3S, AP-HP, Groupe Hospitalier Pitié-Salpêtrière Charles Foix, Paris, France.,Neurophysiologie Respiratoire Expérimentale et Clinique, Sorbonne Université, INSERM, UMRS1158, Paris, France
| | - V Lemiale
- Hôpital Saint-Louis, Paris, France.,Center of Epidemiology and Biostatistics, Paris Diderot Sorbonne University, Paris, France
| | - A Pesenti
- Università degli Studi di Milano, Dipartimento di Fisopatologia Medico-Chirurgica e dei Trapianti, Milan, Italy.,Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - E D Riviello
- Division of Pulmonary, Critical Care and Sleep Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA
| | - T Mauri
- Università degli Studi di Milano, Dipartimento di Fisopatologia Medico-Chirurgica e dei Trapianti, Milan, Italy.,Department of Anesthesia, Critical Care and Emergency, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy
| | - J Mancebo
- Servei de Medicina Intensiva, Hospital Universitari Sant Pau, Barcelona, Spain
| | - L Brochard
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| | - K Burns
- Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
16
|
Aviv M, Halperin-Sternfeld M, Grigoriants I, Buzhansky L, Mironi-Harpaz I, Seliktar D, Einav S, Nevo Z, Adler-Abramovich L. Improving the Mechanical Rigidity of Hyaluronic Acid by Integration of a Supramolecular Peptide Matrix. ACS Appl Mater Interfaces 2018; 10:41883-41891. [PMID: 30211538 DOI: 10.1021/acsami.8b08423] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Hyaluronic acid (HA), a major component of the extracellular matrix, is an attractive material for various medical applications. Yet, its low mechanical rigidity and fast in vivo degradation hinder its utilization. Here, we demonstrate the reinforcement of HA by its integration with a low-molecular-weight peptide hydrogelator to produce a composite hydrogel. The formulation of HA with the fluorenylmethoxycarbonyl diphenylalanine (FmocFF) peptide, one of the most studied self-assembling hydrogel-forming building blocks, showing notable mechanical properties, resulted in the formation of stable, homogeneous hydrogels. Electron microscopy analysis demonstrated a uniform distribution of the two matrices in the composite forms. The composite hydrogels showed improved mechanical properties and stability to enzymatic degradation while maintaining their biocompatibility. Moreover, the storage modulus of the FmocFF/HA composite hydrogels reached up to 25 kPa. The composite hydrogels allowed sustained release of curcumin, a hydrophobic polyphenol showing antioxidant, anti-inflammatory, and antitumor activities. Importantly, the rate of curcumin release was modulated as a function of the concentration of the FmocFF peptide within the hydrogel matrix. This work provides a new approach for conferring mechanical rigidity and stability to HA without the need of cross-linking, thus potentially facilitating its utilization in different clinical applications, such as sustained drug release.
Collapse
Affiliation(s)
- Moran Aviv
- School of Mechanical Engineering , Afeka Tel Aviv Academic College of Engineering , Tel Aviv 6910717 , Israel
| | | | | | | | - Iris Mironi-Harpaz
- Faculty of Biomedical Engineering , Technion-Israel Institute of Technology , Haifa 3200003 , Israel
| | - Dror Seliktar
- Faculty of Biomedical Engineering , Technion-Israel Institute of Technology , Haifa 3200003 , Israel
| | | | | | | |
Collapse
|
17
|
Weiniger CF, Yakirevich-Amir N, Sela HY, Gural A, Ioscovich A, Einav S. Retrospective study to investigate fresh frozen plasma and packed cell ratios when administered for women with postpartum hemorrhage, before and after introduction of a massive transfusion protocol. Int J Obstet Anesth 2018; 36:34-41. [PMID: 30245260 DOI: 10.1016/j.ijoa.2018.08.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 07/21/2018] [Accepted: 08/02/2018] [Indexed: 12/31/2022]
Abstract
BACKGROUND Administration of packed red blood cells (PRBC) and fresh frozen plasma (FFP) to women with postpartum hemorrhage (PPH) before and after introduction of a massive transfusion protocol. METHODS The retrospective PPH study cohort of two tertiary centers was identified using blood bank records, verified by patient electronic medical records. We identified women transfused with ≥3 units PRBC in a short time period within 24 hours of delivery. Since 2010, both centers have used a protocol using 1:1 FFP:PRBC ratios. Demographic, obstetric, and blood management data were retrieved from medical records. Outcome measures included estimated blood loss, blood product administration, and hematologic variables. RESULTS 273 women were included, 112 (41.0%) prior to introduction of the protocol (2004-2009) and 161 (59.0%) afterwards (2010-2014). The frequency of women managed with 1:1 FFP:PRBC ratios was similar before 55/112 (49.1%) and after 83/161 (51.6%) introduction of the protocol (P=0.69). There was strong correlation between PRBC units transfused and the FFP:PRBC transfusion ratio (R-square 0.866, P <0.0001), demonstrating that as the number of transfused PRBC units increased, FFP:PRBC ratios became closer to 1:1. There were no outcome differences between women managed before and after introduction of the protocol. CONCLUSIONS Among women with PPH receiving ≥3 PRBC units within a short period of time, it appears that factors other than the existence of our massive transfusion protocol influence the number and ratio of PRBC and FFP units transfused. Blood products were not transfused according to exact ratios, even when guided by a protocol.
Collapse
Affiliation(s)
- C F Weiniger
- Department of Anesthesiology and Critical Care Medicine, Hadassah Hebrew University Medical Center and Division of Anesthesia, Critical Care and Pain, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
| | | | - H Y Sela
- Department of Obstetrics and Gynecology, Shaare Zedek Medical Center, Israel
| | - A Gural
- Department of Hematology, Hadassah Hebrew University Medical Center, Jerusalem, Israel
| | - A Ioscovich
- Department of Anesthesiology, Shaare Zedek Medical Center, Jerusalem, Israel
| | - S Einav
- Intensive Care Unit of the Shaare Zedek Medical Center and Hebrew University School of Medicine, Jerusalem, Israel
| |
Collapse
|
18
|
Zieleskiewicz L, Bouvet L, Einav S, Duclos G, Leone M. Diagnostic point‐of‐care ultrasound: applications in obstetric anaesthetic management. Anaesthesia 2018; 73:1265-1279. [DOI: 10.1111/anae.14354] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2018] [Indexed: 12/13/2022]
Affiliation(s)
- L. Zieleskiewicz
- Department of Anaesthesia and Intensive Care Medicine University Hospital of Marseille Aix Marseille university C2VN France
| | - L. Bouvet
- Department of Anaesthesia and Intensive Care Medicine Hospices Civils de Lyon Hôpital Femme Mère Enfant Bron France
| | - S. Einav
- General Intensive Care Shaare Zedek Medical Centre Hebrew University Faculty of Medicine Jerusalem Israel
| | - G. Duclos
- Department of Anaesthesia and Intensive Care Medicine University Hospital of Marseille Marseille France
| | - M. Leone
- Department of Anaesthesia and Intensive Care Medicine University Hospital of Marseille Marseille France
| |
Collapse
|
19
|
Affiliation(s)
- Shmuel Einav
- Department of Biomedical Engineering and CEWIT, Stony Brook University, USA; Department of Biomedical Engineering, Tel Aviv University, Israel.
| | - Danny Bluestein
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA.
| | - Oren M Rotman
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA.
| |
Collapse
|
20
|
Abstract
The occurrence of late complications in implanted cardiac prosthetic valves has emphasized the need for the development of an animal model in which these complications are reproducible. Sheep constitute an excellent model for chronical and pathological studies of prosthetic devices. In our experience, survival of sheep following implantation of prosthetic valves is closely related to postoperative serum colloid osmotic pressure (C.O.P.). The normal range as measured in 28 healthy sheep was 16.67 ± 0.55 mm Hg. A protocol was developed to maintain the colloid hydrostatic pressure gradient (C.H.P.G.) as close as possible to the normal physiological range, and to delay the extubation until the C.O.P. was within this range, and the C.H.P.G. > 7mm Hg. Using the above protocol, a new tri-leaflet Polyurethane valve was inserted into eight, five to seven month old sheep in place of the mitral and tricuspidal valves. One hour after terminating the extacorporeal circuit, the C.O.P. was measured at 13.10 ± 0.96; but within five to six hours, it rose to 17.1 ± 1.1. During the same period, the C.H.P.G. increased from 3.02 ± 0.96 to 7.6 ± 0.50 mm Hg. The postoperative period was uneventful, and all animals survived. We have thus concluded that the routine measurement and monitoring of C.O.P. constitutes a guide of great clinical importance.
Collapse
Affiliation(s)
- J. Barak
- Massachusetts General Hospital, Boston, MA-U.S.A
| | - S. Einav
- Tel Aviv University, Biomedical Engineering, Ramat Aviv-Israel
| | - A. Tadmor
- Tel Aviv Medical Center and Tel Aviv University
| | - B. Vidne
- Tel Aviv Medical Center and Tel Aviv University
| | - W.G. Austen
- Massachusetts General Hospital, Boston, MA-U.S.A
| |
Collapse
|
21
|
O'Leary RA, Einav S, Leone M, Madách K, Martin C, Martin-Loeches I. Management of invasive candidiasis and candidaemia in critically ill adults: expert opinion of the European Society of Anaesthesia Intensive Care Scientific Subcommittee. J Hosp Infect 2018; 98:382-390. [DOI: 10.1016/j.jhin.2017.11.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/29/2017] [Indexed: 12/27/2022]
|
22
|
Abstract
Blood flowing through a prosthetic heart valve can be damaged by flow-induced shear forces. Fluid dynamics variables and geometric factors play an important role in the evaluation of shear-stress-related blood damage. Central-flow prosthetic valves have been considered as an optimal replacement for mechanical and biological valves. Recently it was shown that shear stress distribution along the surface of a polyurethane cusp reaches values that can damage the blood elements. A mathematical model correlating the effects of shear stresses on blood corpuscles with clinical findings was employed in vitro. The model can be applied to the effects of blood-surface interaction and is of clinical relevance
Collapse
Affiliation(s)
- S. Einav
- Biomedical Engineering Program, Tel Aviv University - Israel
| | - H. Reul
- Helmholtz Institute for Biomedical Techniques, RWTH Aachen - Germany
| | - G. Rau
- Helmholtz Institute for Biomedical Techniques, RWTH Aachen - Germany
| | - D. Elad
- Biomedical Engineering Program, Tel Aviv University - Israel
| |
Collapse
|
23
|
Zieleskiewicz L, Noel A, Duclos G, Haddam M, Delmas A, Bechis C, Loundou A, Blanc J, Mignon A, Bouvet L, Einav S, Bourgoin A, Leone M. Can point-of-care ultrasound predict spinal hypotension during caesarean section? A prospective observational study. Anaesthesia 2017; 73:15-22. [PMID: 28986931 DOI: 10.1111/anae.14063] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2017] [Indexed: 12/18/2022]
Abstract
Spinal anaesthesia for elective caesarean section is associated with maternal hypotension, secondary to alteration of sympathetic tone and hypovolemia, in up to 70% of cases. Measurement of the subaortic variation in the velocity time integral (VTI) after passive leg raising allows prediction of fluid responsiveness. Our objective, in this prospective single-centre observational study, was to assess the ability of change in VTI after 45° passive leg raising to predict hypotension after spinal anaesthesia. Ultrasound measurements were performed just before elective caesarean section. Anaesthesia, intravenous coloading and prophylactic vasopressor treatment were standardised according to current guidelines. We studied 40 women. Hypotension occurred in 17 (45%) women. The area (95%CI) under the receiver operating characteristics (ROC) curve for the prediction of spinal hypotension was 0.8 (0.6-0.9; p = 0.0001). Seventeen women had a change in VTI with leg elevation ≤ 8%, which was predictive for not developing hypotension, and 11 had a change ≥ 21%, predictive for hypotension. The grey zone between 8% and 21%, with inconclusive values, included 12 women. We suggest that cardiac ultrasound provides characterisation of the risk of hypotension following spinal anaesthesia at elective caesarean section, and therefore may allow individualised strategies for prevention and management.
Collapse
Affiliation(s)
- L Zieleskiewicz
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - A Noel
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - G Duclos
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - M Haddam
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - A Delmas
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - C Bechis
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - A Loundou
- Epidemiology and Methodology Department, Aix Marseille University, Marseille, France
| | - J Blanc
- Department of Obstetrics and Gynecology, Aix Marseille University, Marseille, France
| | - A Mignon
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - L Bouvet
- Department of Anaesthesia and Intensive Care Medicine, Hospices Civils de Lyon, Hôpital Femme Mère Enfant, Bron, France
| | - S Einav
- General Intensive Care, Shaare Zedek Medical Centre and Hebrew University Faculty of Medicine, Jerusalem, Israel
| | - A Bourgoin
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France
| | - M Leone
- Department of Anaesthesia and Intensive Care Medicine, University Hospital of Marseille, Marseille, France.,Centre d'Investigation Clinique 1409, AP-HM, Aix Marseille University, Marseille, France
| |
Collapse
|
24
|
Mendez Y, Garcia I, Einav S, Surani S, Varon J. P201 Race as a factor of providing care. Chest 2017. [DOI: 10.1016/j.chest.2017.04.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
|
25
|
Arnaud D, Almaguer A, Mendez Y, Garcia I, Einav S, Varon J. P202 Does religion affect the care given by providers of sexual offender patients? Chest 2017. [DOI: 10.1016/j.chest.2017.04.106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
26
|
Weiss D, Avraham S, Guttlieb R, Gasner L, Lotman A, Rotman OM, Einav S. Mechanical Compression Effects on the Secretion of vWF and IL-8 by Cultured Human Vein Endothelium. PLoS One 2017; 12:e0169752. [PMID: 28081186 PMCID: PMC5230793 DOI: 10.1371/journal.pone.0169752] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 12/21/2016] [Indexed: 01/07/2023] Open
Abstract
Short peripheral catheters are ubiquitous in today's healthcare environment enabling effective delivery of fluids and medications directly into a patient's vasculature. However, complications related to their use, such as short peripheral catheter thrombophlebitis (SPCT), affect up to 80% of hospitalized patients. While indwelling within the vein, the catheters exert prolonged constant pressure upon the endothelium which can trigger inflammation processes. We have developed and studied an in-vitro model of cultured endothelial cells subjected to mechanical compression of modular self-designed weights, and explored their inflammatory response by quantification of two key biomarkers- vWF and IL-8. Evaluation was performed by ELISA immunoassay and processing of vWF-labeled immunofluorescence images. We found that application of weights correspond to 272 Pa yielded increased release of vWF and IL-8 up to 150% and 250% respectively, comparing to the exertion of 136 Pa. Analyses of the immunofluorescence images revealed significantly longer and more extracellular vWF-strings as well as higher intensity stained-pixels in cells exposed to elevated pressures. The release of both factors found to be significantly dependent on the extent of the exerted pressure. The research shed a light on the relationship between induced mechanical compression and the pathogenesis of SPCT. Minimizing, let alone eliminating the contact between the catheter and the vein wall will mitigate the pressure acting on the endothelium, thereby reducing the secretion of inflammatory factors and lessen the incidence of SPCT.
Collapse
Affiliation(s)
- Dar Weiss
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
| | - Sharon Avraham
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Ruth Guttlieb
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Lee Gasner
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Alina Lotman
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Oren M. Rotman
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Shmuel Einav
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv, Israel
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| |
Collapse
|
27
|
Rotman OM, Zaretsky U, Shitzer A, Einav S. Pressure drop and arterial compliance – Two arterial parameters in one measurement. J Biomech 2017; 50:130-137. [DOI: 10.1016/j.jbiomech.2016.11.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Accepted: 11/02/2016] [Indexed: 11/15/2022]
|
28
|
Weiss D, Rotman OM, Einav S. Quantitative T2 mapping for detection and quantification of thrombophlebitis in a rabbit model. J Biomech 2016; 50:151-157. [PMID: 27866674 DOI: 10.1016/j.jbiomech.2016.11.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 11/02/2016] [Indexed: 11/29/2022]
Abstract
Short peripheral catheter thrombophlebitis (SPCT), a sterile inflammation of the vein wall, is the most common complication associated with short peripheral catheters (SPCs) and affects up to 80% of hospitalized patients receiving IV therapy. Extensive research efforts have been devoted for improvement and optimization of the catheter material, but means for examination of any novel design are limited, inaccurate and require costly comprehensive pre-clinical and clinical trials. Therefore, there is a conclusive need for a reliable quantitative method for evaluation of SPCT, in particular for research purposes examining the thrombophlebitis-related symptoms of any novel catheter design. In this study, we developed for the first time a quantitative MRI based tool for evaluation of SPCT. The extent and severity of SPCT caused by two different commercially available SPCs with known predisposition for thrombophlebitis, were studied in a rabbit model. MRI analysis was consistent with the standardized pathology evaluation and showed remarkable difference in the percent of edema between the experimental groups. These differences were in line with previous studies and provide evidence that this type of analysis may be useful for future assessment of SPCT in vivo. As a non-invasive method, it may constitute a cost effective solution for examination of new catheters and other medical devices, thereby reducing the need for animal sacrifice.
Collapse
Affiliation(s)
- Dar Weiss
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Oren M Rotman
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| | - Shmuel Einav
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel; Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794, USA
| |
Collapse
|
29
|
Soifer E, Weiss D, Marom G, Einav S. The effect of pathologic venous valve on neighboring valves: fluid-structure interactions modeling. Med Biol Eng Comput 2016; 55:991-999. [PMID: 27663560 DOI: 10.1007/s11517-016-1575-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 09/15/2016] [Indexed: 11/27/2022]
Abstract
Understanding the hemodynamics surrounding the venous valve environment is of a great importance for prosthetic valves design. The present study aims to evaluate the effect of leaflets' stiffening process on the venous valve hemodynamics, valve's failure on the next proximal valve hemodynamics and valve's failure in a secondary daughter vein on the healthy valve hemodynamics in the main vein when both of these valves are distal to a venous junction. Fully coupled, two-way fluid-structure interaction computational models were developed and employed. The sinus pocket region experiences the lowest fluid shear stress, and the base region of the sinus side of the leaflet experiences the highest tissue stress. The leaflets' stiffening increases the tissue stress the valve is experiencing in a very low fluid shear region. A similar effect occurs with the proximal healthy valve as a consequence of the distal valve's failure and with the mother vein valve as a consequence of daughter vein valve's failure. Understanding the described mechanisms may be helpful for elucidating the venous valve stiffness-function relationship in nature, the reasons for a retrograde development of reflux and the relationship between venous valves located near venous junctions, and for designing better prosthetic valves and for improving their positioning.
Collapse
Affiliation(s)
- Elina Soifer
- The Department of Biomedical Engineering, Tel-Aviv University, Tel-Aviv, Israel.
| | - Dar Weiss
- The Department of Biomedical Engineering, Tel-Aviv University, Tel-Aviv, Israel
| | - Gil Marom
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Shmuel Einav
- The Department of Biomedical Engineering, Tel-Aviv University, Tel-Aviv, Israel.,Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| |
Collapse
|
30
|
Matichin H, Einav S, Spitzer H. Single additive mechanism predicts lateral interactions effects-computational model. J Opt Soc Am A Opt Image Sci Vis 2015; 32:2247-2259. [PMID: 26831379 DOI: 10.1364/josaa.32.002247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The mechanism underlying the lateral interactions (LI) phenomenon is still an enigma. Over the years, several groups have tried to explain the phenomenon and suggested models to predict its psychophysical results. Most of these models comprise both inhibitory and facilitatory mechanisms for describing the LI phenomenon. Their studies' assumption that a significant inhibition mechanism exists is based on the classical interpretation of the threshold elevation perceived in psychophysical experiments. In this work, we suggest a different interpretation of the threshold elevation obtained experimentally. Our model proposes and demonstrates how a facilitatory additive mechanism can solely predict both the facilitation and "inhibition" aspects of the phenomenon, without the need for an additional inhibitory mechanism, at least for the two flankers' configurations. Though the model is simple it succeeds to predict the LI effect under a large variety of stimuli configurations and parameters. The model is in agreement with both classical and recent psychophysical and neurophysiological results. We suggest that the LI mechanism plays a role in creating an educated guess to form a continuation of gratings and textures based on the surrounding visual stimuli.
Collapse
|
31
|
Rotman OM, Weiss D, Zaretsky U, Shitzer A, Einav S. High accuracy differential pressure measurements using fluid-filled catheters - A feasibility study in compliant tubes. J Biomech 2015; 48:3543-8. [PMID: 26087881 DOI: 10.1016/j.jbiomech.2015.05.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 05/09/2015] [Accepted: 05/24/2015] [Indexed: 11/24/2022]
Abstract
High accuracy differential pressure measurements are required in various biomedical and medical applications, such as in fluid-dynamic test systems, or in the cath-lab. Differential pressure measurements using fluid-filled catheters are relatively inexpensive, yet may be subjected to common mode pressure errors (CMP), which can significantly reduce the measurement accuracy. Recently, a novel correction method for high accuracy differential pressure measurements was presented, and was shown to effectively remove CMP distortions from measurements acquired in rigid tubes. The purpose of the present study was to test the feasibility of this correction method inside compliant tubes, which effectively simulate arteries. Two tubes with varying compliance were tested under dynamic flow and pressure conditions to cover the physiological range of radial distensibility in coronary arteries. A third, compliant model, with a 70% stenosis severity was additionally tested. Differential pressure measurements were acquired over a 3 cm tube length using a fluid-filled double-lumen catheter, and were corrected using the proposed CMP correction method. Validation of the corrected differential pressure signals was performed by comparison to differential pressure recordings taken via a direct connection to the compliant tubes, and by comparison to predicted differential pressure readings of matching fluid-structure interaction (FSI) computational simulations. The results show excellent agreement between the experimentally acquired and computationally determined differential pressure signals. This validates the application of the CMP correction method in compliant tubes of the physiological range for up to intermediate size stenosis severity of 70%.
Collapse
Affiliation(s)
- Oren Moshe Rotman
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
| | - Dar Weiss
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Uri Zaretsky
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| | - Avraham Shitzer
- Faculty of Mechanical Engineering, Technion, Israel Institute of Technology, Haifa 32000, Israel
| | - Shmuel Einav
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel
| |
Collapse
|
32
|
Abstract
A reliable intravenous (IV) access into the upper extremity veins requires the insertion of a temporary short peripheral catheter (SPC). This so common procedure is, however, associated with a risk of developing short peripheral catheter thrombophlebitis (SPCT) which causes distress and potentially prolongs patient hospitalization. We have developed and studied a biomechanical SPC-vein computational model during an IV procedure, and explored the biomechanical effects of repeated IV episodes on onset and reoccurrences of SPCT. The model was used to determine the effects of different insertion techniques as well as inter-patient biological variability on the catheter-vein wall contact pressures and wall deformations. We found that the maximal pressure exerted upon the vein wall was inhomogeneously distributed, and that the bending region was exposed to significantly greater pressures and deformations. The maximal exerted contact pressure on the inner vein's wall was 2938 Pa. The maximal extent of the SPC penetration into the vein wall reached 3.6 μm, which corresponds to approximately 100% of the average height of the inner layer, suggesting local squashing of endothelial cells at the contact site. The modelling describes a potential biomechanical damage pathway that can explain the reoccurrence of SPCT.
Collapse
Affiliation(s)
- Dar Weiss
- a Department of Biomedical Engineering , Faculty of Engineering, Tel Aviv University , Tel Aviv 69978 , Israel
| | - Amit Gefen
- a Department of Biomedical Engineering , Faculty of Engineering, Tel Aviv University , Tel Aviv 69978 , Israel
| | - Shmuel Einav
- a Department of Biomedical Engineering , Faculty of Engineering, Tel Aviv University , Tel Aviv 69978 , Israel.,b Stony Brook University , Stony Brook , NY , USA
| |
Collapse
|
33
|
Xenos M, Labropoulos N, Rambhia S, Alemu Y, Einav S, Tassiopoulos A, Sakalihasan N, Bluestein D. Progression of abdominal aortic aneurysm towards rupture: refining clinical risk assessment using a fully coupled fluid-structure interaction method. Ann Biomed Eng 2014; 43:139-53. [PMID: 25527320 DOI: 10.1007/s10439-014-1224-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 12/09/2014] [Indexed: 01/12/2023]
Abstract
Rupture of abdominal aortic aneurysm (AAA) is associated with high mortality rates. Risk of rupture is multi-factorial involving AAA geometric configuration, vessel tortuosity, and the presence of intraluminal pathology. Fluid structure interaction (FSI) simulations were conducted in patient based computed tomography scans reconstructed geometries in order to monitor aneurysmal disease progression from normal aortas to non-ruptured and contained ruptured AAA (rAAA), and the AAA risk of rupture was assessed. Three groups of 8 subjects each were studied: 8 normal and 16 pathological (8 non-ruptured and 8 rAAA). The AAA anatomical structures segmented included the blood lumen, intraluminal thrombus (ILT), vessel wall, and embedded calcifications. The vessel wall was described with anisotropic material model that was matched to experimental measurements of AAA tissue specimens. A statistical model for estimating the local wall strength distribution was employed to generate a map of a rupture potential index (RPI), representing the ratio between the local stress and local strength distribution. The FSI simulations followed a clear trend of increasing wall stresses from normal to pathological cases. The maximal stresses were observed in the areas where the ILT was not present, indicating a potential protective effect of the ILT. Statistically significant differences were observed between the peak systolic stress and the peak stress at the mean arterial pressure between the three groups. For the ruptured aneurysms, where the geometry of intact aneurysm was reconstructed, results of the FSI simulations clearly depicted maximum wall stress at the a priori known location of rupture. The RPI mapping indicated several distinct regions of high RPI coinciding with the actual location of rupture. The FSI methodology demonstrates that the aneurysmal disease can be described by numerical simulations, as indicated by a clear trend of increasing aortic wall stresses in the studied groups, (normal aortas, AAAs and rAAAs). Ultimately, the results demonstrate that FSI wall stress mapping and RPI can be used as a tool for predicting the potential rupture of an AAA by predicting the actual rupture location, complementing current clinical practice by offering a predictive diagnostic tool for deciding whether to intervene surgically or spare the patient from an unnecessary risky operation.
Collapse
Affiliation(s)
- Michalis Xenos
- Department of Mathematics, University of Ioannina, Ioannina, Greece
| | | | | | | | | | | | | | | |
Collapse
|
34
|
Chiu WC, Girdhar G, Xenos M, Alemu Y, Soares JS, Einav S, Slepian M, Bluestein D. Thromboresistance comparison of the HeartMate II ventricular assist device with the device thrombogenicity emulation- optimized HeartAssist 5 VAD. J Biomech Eng 2014; 136:021014. [PMID: 24337144 DOI: 10.1115/1.4026254] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Indexed: 11/08/2022]
Abstract
Approximately 7.5 × 106 patients in the US currently suffer from end-stage heart failure. The FDA has recently approved the designations of the Thoratec HeartMate II ventricular assist device (VAD) for both bridge-to-transplant and destination therapy (DT) due to its mechanical durability and improved hemodynamics. However, incidence of pump thrombosis and thromboembolic events remains high, and the life-long complex pharmacological regimens are mandatory in its VAD recipients. We have previously successfully applied our device thrombogenicity emulation (DTE) methodology for optimizing device thromboresistance to the Micromed Debakey VAD, and demonstrated that optimizing device features implicated in exposing blood to elevated shear stresses and exposure times significantly reduces shear-induced platelet activation and significantly improves the device thromboresistance. In the present study, we compared the thrombogenicity of the FDA-approved HeartMate II VAD with the DTE-optimized Debakey VAD (now labeled HeartAssist 5). With quantitative probability density functions of the stress accumulation along large number of platelet trajectories within each device which were extracted from numerical flow simulations in each device, and through measurements of platelet activation rates in recirculation flow loops, we specifically show that: (a) Platelets flowing through the HeartAssist 5 are exposed to significantly lower stress accumulation that lead to platelet activation than the HeartMate II, especially at the impeller-shroud gap regions (b) Thrombus formation patterns observed in the HeartMate II are absent in the HeartAssist 5 (c) Platelet activation rates (PAR) measured in vitro with the VADs mounted in recirculation flow-loops show a 2.5-fold significantly higher PAR value for the HeartMate II. This head to head thrombogenic performance comparative study of the two VADs, one optimized with the DTE methodology and one FDA-approved, demonstrates the efficacy of the DTE methodology for drastically reducing the device thrombogenic potential, validating the need for a robust in silico/in vitro optimization methodology for improving cardiovascular devices thromboresistance.
Collapse
|
35
|
Rotman OM, Zaretsky U, Shitzer A, Einav S. Method for high accuracy differential pressure measurements using fluid-filled catheters. Ann Biomed Eng 2014; 42:1705-16. [PMID: 24809725 DOI: 10.1007/s10439-014-1026-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 05/02/2014] [Indexed: 11/29/2022]
Abstract
The advantage of measuring differential pressure using fluid-filled catheters is that the system is relatively inexpensive, but the readings are not accurate and affected by the common mode pressure (CMP) distortion. High accuracy differential pressure measurements are required in various biomedical applications, such as in fluid-dynamic test rigs, or in the cath-lab, from cardiac valves efficacy to functional assessment of arterial stenoses. We have designed and built a unique system in which the pressure difference was measured along the fluid flow inside a rigid circular tube using a fluid-filled double-lumen catheter. The differential pressure measurements were taken across two side-holes near the catheter distal tip, spaced apart by 3 cm. The goal was to overcome the CMP error, which significantly distorted the output differential pressure signal and to formulate a restoration factor. A restoration formula was developed based on simultaneous gauge pressure measurements, and was tested in several different cases. Several representative cases are presented and show that the common mode artifact was reduced by factors of 12-27. The restored pressure gradient signal was validated using direct pressure drop measurements, and showed very good agreement.
Collapse
Affiliation(s)
- Oren M Rotman
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, 69978, Tel Aviv, Israel,
| | | | | | | |
Collapse
|
36
|
Ashkenazi I, Turégano-Fuentes F, Einav S, Kessel B, Alfici R, Olsha O. Pitfalls to avoid in the medical management of mass casualty incidents following terrorist bombings: the hospital perspective. Eur J Trauma Emerg Surg 2014; 40:445-50. [PMID: 26816239 DOI: 10.1007/s00068-014-0403-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Accepted: 04/08/2014] [Indexed: 11/26/2022]
Abstract
BACKGROUND The unique patterns of injury following explosions together with the involvement of numerous physicians, most of whom are not experienced in trauma, may create problems in the medical management of mass casualty incidents. METHODS Four hundred patient files admitted in 19 mass casualty events following bombing incidents were reviewed and possible areas which could impact survival were defined. RESULTS Forty-nine (9.3 %) patients had an Injury Severity Score ≥16. Of 205 patients in whom triage decisions were available, 5 of 25 severely injured patients were undertriaged by the triage officers at the door of the hospital. Following primary evaluation inside the emergency department critical injuries in two patients were missed due to distracting, less serious injuries. Of 68 (16.1 %) patients who were operated, 28 were in need of either immediate, urgent or high-priority operations. Except for neurosurgical cases which needed to be transferred to other hospitals, there was no delay in surgery. One patient underwent negative laparotomy. There were 15 in-hospital deaths, 6 of which were deemed as either anticipated or unanticipated mortality with possibility for improvement. CONCLUSION Medical management should be evaluated following MCIs as this may illustrate possible problems which many need to be addressed in contingency planning.
Collapse
Affiliation(s)
- I Ashkenazi
- Surgery Department, Hillel Yaffe Medical Center, P.O.Box 169, 38100, Hadera, Israel.
| | - F Turégano-Fuentes
- Emergency Surgery Department, Gregorio Marañon Medical Center, Madrid, Spain
| | - S Einav
- Intensive Care Unit, Shaare Zedek Medical Center, Jerusalem, Israel
| | - B Kessel
- Trauma Unit, Hillel Yaffe Medical Center, Hadera, Israel
| | - R Alfici
- Surgery Department, Hillel Yaffe Medical Center, P.O.Box 169, 38100, Hadera, Israel
| | - O Olsha
- Department of Surgery, Shaare Zedek Medical Center, Jerusalem, Israel
| |
Collapse
|
37
|
Shav D, Gotlieb R, Zaretsky U, Elad D, Einav S. Wall shear stress effects on endothelial-endothelial and endothelial-smooth muscle cell interactions in tissue engineered models of the vascular wall. PLoS One 2014; 9:e88304. [PMID: 24520363 PMCID: PMC3919748 DOI: 10.1371/journal.pone.0088304] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 01/05/2014] [Indexed: 12/30/2022] Open
Abstract
Vascular functions are affected by wall shear stresses (WSS) applied on the endothelial cells (EC), as well as by the interactions of the EC with the adjacent smooth muscle cells (SMC). The present study was designed to investigate the effects of WSS on the endothelial interactions with its surroundings. For this purpose we developed and constructed two co-culture models of EC and SMC, and compared their response to that of a single monolayer of cultured EC. In one co-culture model the EC were cultured on the SMC, whereas in the other model the EC and SMC were cultured on the opposite sides of a membrane. We studied EC-matrix interactions through focal adhesion kinase morphology, EC-EC interactions through VE-Cadherin expression and morphology, and EC-SMC interactions through the expression of Cx43 and Cx37. In the absence of WSS the SMC presence reduced EC-EC connectivity but produced EC-SMC connections using both connexins. The exposure to WSS produced discontinuity in the EC-EC connections, with a weaker effect in the co-culture models. In the EC monolayer, WSS exposure (12 and 4 dyne/cm2 for 30 min) increased the EC-EC interaction using both connexins. WSS exposure of 12 dyne/cm2 did not affect the EC-SMC interactions, whereas WSS of 4 dyne/cm2 elevated the amount of Cx43 and reduced the amount of Cx37, with a different magnitude between the models. The reduced endothelium connectivity suggests that the presence of SMC reduces the sealing properties of the endothelium, showing a more inflammatory phenotype while the distance between the two cell types reduced their interactions. These results demonstrate that EC-SMC interactions affect EC phenotype and change the EC response to WSS. Furthermore, the interactions formed between the EC and SMC demonstrate that the 1-side model can simulate better the arterioles, while the 2-side model provides better simulation of larger arteries.
Collapse
Affiliation(s)
- Dalit Shav
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
| | - Ruth Gotlieb
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Uri Zaretsky
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - David Elad
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Shmuel Einav
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
38
|
Slepian MJ, Alemu Y, Girdhar G, Soares JS, Smith RG, Einav S, Bluestein D. The Syncardia(™) total artificial heart: in vivo, in vitro, and computational modeling studies. J Biomech 2013; 46:266-75. [PMID: 23305813 DOI: 10.1016/j.jbiomech.2012.11.032] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 11/15/2012] [Indexed: 02/07/2023]
Abstract
The SynCardia(™) total artificial heart (TAH) is the only FDA-approved TAH in the world. The SynCardia(™) TAH is a pneumatically driven, pulsatile system capable of flows of >9L/min. The TAH is indicated for use as a bridge to transplantation (BTT) in patients at imminent risk of death from non-reversible bi-ventricular failure. In the Pivotal US approval trial the TAH achieved a BTT rate of >79%. Recently a multi-center, post-market approval study similarly demonstrated a comparable BTT rate. A major milestone was recently achieved for the TAH, with over 1100 TAHs having been implanted to date, with the bulk of implantation occurring at an ever increasing rate in the past few years. The TAH is most commonly utilized to save the lives of patients dying from end-stage bi-ventricular heart failure associated with ischemic or non-ischemic dilated cardiomyopathy. Beyond progressive chronic heart failure, the TAH has demonstrated great efficacy in supporting patients with acute irreversible heart failure associated with massive acute myocardial infarction. In recent years several diverse clinical scenarios have also proven to be well served by the TAH including severe heart failure associated with advanced congenital heart disease. failed or burned-out transplants, infiltrative and restrictive cardiomyopathies and failed ventricular assist devices. Looking to the future a major unmet need remains in providing total heart support for children and small adults. As such, the present TAH design must be scaled to fit the smaller patient, while providing equivalent, if not superior flow characteristics, shear profiles and overall device thrombogenicity. To aid in the development of a new "pediatric," TAH an engineering methodology known as "Device Thrombogenicity Emulation (DTE)", that we have recently developed and described, is being employed. Recently, to further our engineering understanding of the TAH, as steps towards next generation designs we have: (1) assessed of the degree of platelet reactivity induced by the present clinical 70 cc TAH using a closed loop platelet activity state assay, (2) modeled the motion of the TAH pulsatile mobile diaphragm, and (3) performed fluid-structure interactions and assessment of the flow behavior through inflow and outflow regions of the TAH fitted with modern bi-leaflet heart valves. Developing a range of TAH devices will afford biventricular replacement therapy to a wide range of patients, for both short and long-term therapy.
Collapse
Affiliation(s)
- Marvin J Slepian
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA.
| | | | | | | | | | | | | |
Collapse
|
39
|
|
40
|
Bluestein D, Girdhar G, Einav S, Slepian MJ. Device thrombogenicity emulation: a novel methodology for optimizing the thromboresistance of cardiovascular devices. J Biomech 2012; 46:338-44. [PMID: 23219278 DOI: 10.1016/j.jbiomech.2012.11.033] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 11/15/2012] [Indexed: 11/18/2022]
Abstract
Thrombotic complications with mechanical circulatory support (MCS) devices remain a critical limitation to their long-term use. Device-induced shear forces may enhance the thrombotic potential of MCS devices through chronic activation of platelets, with a known dose-time response of the platelets to the accumulated stress experienced while flowing through the device-mandating complex, lifelong anticoagulation therapy. To enhance the thromboresistance of these devices for facilitating their long-term use, a universal predictive methodology entitled device thrombogenicity emulation (DTE) was developed. DTE is aimed at optimizing the thromboresistance of any MCS device. It is designed to test device-mediated thrombogenicity, coupled with virtual design modifications, in an iterative approach. This disruptive technology combines in silico numerical simulations with in vitro measurements, by correlating device hemodynamics with platelet activity coagulation markers-before and after iterative design modifications aimed at achieving optimized thrombogenic performance. The design changes are first tested in the numerical domain, and the resultant device conditions are then emulated in a hemodynamic shearing device (HSD) in which platelet activity is measured under device emulated conditions. As such, DTE can be easily incorporated during the device research and development phase-achieving minimization of the device thrombogenicity before prototypes are built and tested thereby reducing the ultimate cost of preclinical and clinical trials. The robust capability of this predictive technology is demonstrated here in various MCS devices. The presented examples indicate the potential of DTE for reducing device thrombogenicity to a level that may obviate or significantly reduce the extent of anticoagulation currently mandated for patients implanted with MCS devices for safe long-term clinical use.
Collapse
Affiliation(s)
- Danny Bluestein
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-8151, USA.
| | | | | | | |
Collapse
|
41
|
Girdhar G, Xenos M, Alemu Y, Chiu WC, Lynch BE, Jesty J, Einav S, Slepian MJ, Bluestein D. Device thrombogenicity emulation: a novel method for optimizing mechanical circulatory support device thromboresistance. PLoS One 2012; 7:e32463. [PMID: 22396768 PMCID: PMC3292570 DOI: 10.1371/journal.pone.0032463] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 01/27/2012] [Indexed: 12/22/2022] Open
Abstract
Mechanical circulatory support (MCS) devices provide both short and long term hemodynamic support for advanced heart failure patients. Unfortunately these devices remain plagued by thromboembolic complications associated with chronic platelet activation--mandating complex, lifelong anticoagulation therapy. To address the unmet need for enhancing the thromboresistance of these devices to extend their long term use, we developed a universal predictive methodology entitled Device Thrombogenicity Emulation (DTE) that facilitates optimizing the thrombogenic performance of any MCS device--ideally to a level that may obviate the need for mandatory anticoagulation. DTE combines in silico numerical simulations with in vitro measurements by correlating device hemodynamics with platelet activity coagulation markers--before and after iterative design modifications aimed at achieving optimized thrombogenic performance. DTE proof-of-concept is demonstrated by comparing two rotary Left Ventricular Assist Devices (LVADs) (DeBakey vs HeartAssist 5, Micromed Houston, TX), the latter a version of the former following optimization of geometrical features implicated in device thrombogenicity. Cumulative stresses that may drive platelets beyond their activation threshold were calculated along multiple flow trajectories and collapsed into probability density functions (PDFs) representing the device 'thrombogenic footprint', indicating significantly reduced thrombogenicity for the optimized design. Platelet activity measurements performed in the actual pump prototypes operating under clinical conditions in circulation flow loops--before and after the optimization with the DTE methodology, show an order of magnitude lower platelet activity rate for the optimized device. The robust capability of this predictive technology--demonstrated here for attaining safe and cost-effective pre-clinical MCS thrombo-optimization--indicates its potential for reducing device thrombogenicity to a level that may significantly limit the extent of concomitant antithrombotic pharmacotherapy needed for safe clinical device use.
Collapse
Affiliation(s)
- Gaurav Girdhar
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Michalis Xenos
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Yared Alemu
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Wei-Che Chiu
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Bryan E. Lynch
- MicroMed Cardiovascular Inc., Houston, Texas, United States of America
| | - Jolyon Jesty
- Department of Hematology, Stony Brook University, Stony Brook, New York, United States of America
| | - Shmuel Einav
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Marvin J. Slepian
- Sarver Heart Center, University of Arizona, Tucson, Arizona, United States of America
| | - Danny Bluestein
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| |
Collapse
|
42
|
Rambhia SH, Liang X, Xenos M, Alemu Y, Maldonado N, Kelly A, Chakraborti S, Weinbaum S, Cardoso L, Einav S, Bluestein D. Microcalcifications increase coronary vulnerable plaque rupture potential: a patient-based micro-CT fluid-structure interaction study. Ann Biomed Eng 2012; 40:1443-54. [PMID: 22234864 DOI: 10.1007/s10439-012-0511-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 01/06/2012] [Indexed: 12/01/2022]
Abstract
Asymptomatic vulnerable plaques (VP) in coronary arteries accounts for significant level of morbidity. Their main risk is associated with their rupture which may prompt fatal heart attacks and strokes. The role of microcalcifications (micro-Ca), embedded in the VP fibrous cap, in the plaque rupture mechanics has been recently established. However, their diminutive size offers a major challenge for studying the VP rupture biomechanics on a patient specific basis. In this study, a highly detailed model was reconstructed from a post-mortem coronary specimen of a patient with observed VP, using high resolution micro-CT which captured the microcalcifications embedded in the fibrous cap. Fluid-structure interaction (FSI) simulations were conducted in the reconstructed model to examine the combined effects of micro-Ca, flow phase lag and plaque material properties on plaque burden and vulnerability. This dynamic fibrous cap stress mapping elucidates the contribution of micro-Ca and flow phase lag VP vulnerability independently. Micro-Ca embedded in the fibrous cap produced increased stresses predicted by previously published analytical model, and corroborated our previous studies. The 'micro-CT to FSI' methodology may offer better diagnostic tools for clinicians, while reducing morbidity and mortality rates for patients with vulnerable plaques and ameliorating the ensuing healthcare costs.
Collapse
Affiliation(s)
- S H Rambhia
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
43
|
Fuchs S, Lavi I, Tzang O, Bessler H, Brosh D, Bental T, Dvir D, Einav S, Kornowski R. Intracoronary Monocyte Chemoattractant Protein 1 and Vascular Endothelial Growth Factor Levels Are Associated with Necrotic Core, Calcium and Fibrous Tissue Atherosclerotic Plaque Components: An Intracoronary Ultrasound Radiofrequency Study. Cardiology 2012; 123:125-32. [DOI: 10.1159/000342050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 06/18/2012] [Indexed: 11/19/2022]
|
44
|
Einav S, Helvitz Y, Ronen M, Hersch M. The IPI identifies the window of opportunity for treatment before cardio-respiratory arrest. Resuscitation 2010. [DOI: 10.1016/j.resuscitation.2010.09.179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
45
|
Tsofe A, Yucht Y, Beyil J, Einav S, Spitzer H. Chromatic Vasarely effect. Vision Res 2010; 50:2284-94. [DOI: 10.1016/j.visres.2010.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2009] [Revised: 07/01/2010] [Accepted: 07/02/2010] [Indexed: 10/19/2022]
|
46
|
Rokach A, Cohen R, Shapira N, Einav S, Mandibura A, Bar-Dayan Y. Preparedness for anthrax attack: the effect of knowledge on the willingness to treat patients. Disasters 2010; 34:637-643. [PMID: 20187905 DOI: 10.1111/j.1467-7717.2010.01161.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Little is known about the factors that may impact on the willingness of physicians and nurses to treat patients during a bioterrorism attack. This survey was conducted among 76 randomly selected nurses and physicians in the emergency rooms of three public hospitals in order to analyse the relationship between knowledge, profession and the willingness to treat anthrax. The study finds that the willingness of physicians and nurses to come to work is 50% greater among the group with the highest knowledge about anthrax (P < 0.0001). Within that group, the willingness to treat patients suspected of being infected with anthrax was 37% greater (P < 0.0001) and the willingness to treat patients diagnosed with anthrax was 28% greater (P = 0.004) than in the other groups. These results imply that enhancement of knowledge among health care workers may improve their willingness to come to work and treat patients infected with anthrax during a bioterrorism attack.
Collapse
Affiliation(s)
- Ariel Rokach
- NBC Hospital, Israeli Defense Forces Home Front Command Medical Department, Israel
| | | | | | | | | | | |
Collapse
|
47
|
Xenos M, Rambhia SH, Alemu Y, Einav S, Labropoulos N, Tassiopoulos A, Ricotta JJ, Bluestein D. Patient-based abdominal aortic aneurysm rupture risk prediction with fluid structure interaction modeling. Ann Biomed Eng 2010; 38:3323-37. [PMID: 20552276 DOI: 10.1007/s10439-010-0094-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Accepted: 06/01/2010] [Indexed: 11/30/2022]
Abstract
Elective repair of abdominal aortic aneurysm (AAA) is warranted when the risk of rupture exceeds that of surgery, and is mostly based on the AAA size as a crude rupture predictor. A methodology based on biomechanical considerations for a reliable patient-specific prediction of AAA risk of rupture is presented. Fluid-structure interaction (FSI) simulations conducted in models reconstructed from CT scans of patients who had contained ruptured AAA (rAAA) predicted the rupture location based on mapping of the stresses developing within the aneurysmal wall, additionally showing that a smaller rAAA presented a higher rupture risk. By providing refined means to estimate the risk of rupture, the methodology may have a major impact on diagnostics and treatment of AAA patients.
Collapse
Affiliation(s)
- Michalis Xenos
- Department of Biomedical Engineering, Stony Brook University, HSC T18-030, Stony Brook, NY 11794-8181, USA
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Xenos M, Girdhar G, Alemu Y, Jesty J, Slepian M, Einav S, Bluestein D. Device Thrombogenicity Emulator (DTE)--design optimization methodology for cardiovascular devices: a study in two bileaflet MHV designs. J Biomech 2010; 43:2400-9. [PMID: 20483411 DOI: 10.1016/j.jbiomech.2010.04.020] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 04/15/2010] [Accepted: 04/16/2010] [Indexed: 12/29/2022]
Abstract
Patients who receive prosthetic heart valve (PHV) implants require mandatory anticoagulation medication after implantation due to the thrombogenic potential of the valve. Optimization of PHV designs may facilitate reduction of flow-induced thrombogenicity and reduce or eliminate the need for post-implant anticoagulants. We present a methodology entitled Device Thrombogenicty Emulator (DTE) for optimizing the thrombo-resistance performance of PHV by combining numerical and experimental approaches. Two bileaflet mechanical heart valves (MHV) designs, St. Jude Medical (SJM) and ATS, were investigated by studying the effect of distinct flow phases on platelet activation. Transient turbulent and direct numerical simulations (DNS) were conducted, and stress loading histories experienced by the platelets were calculated along flow trajectories. The numerical simulations indicated distinct design dependent differences between the two valves. The stress loading waveforms extracted from the numerical simulations were programmed into a hemodynamic shearing device (HSD), emulating the flow conditions past the valves in distinct 'hot-spot' flow regions that are implicated in MHV thrombogenicity. The resultant platelet activity was measured with a modified prothrombinase assay, and was found to be significantly higher in the SJM valve, mostly during the regurgitation phase. The experimental results were in excellent agreement with the calculated platelet activation potential. This establishes the utility of the DTE methodology for serving as a test bed for evaluating design modifications for achieving better thrombogenic performance for such devices.
Collapse
Affiliation(s)
- Michalis Xenos
- Department of Biomedical Engineering, Stony Brook University, HSC T18-030, Stony Brook, NY 11794-8181, USA
| | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
Stem cell differentiation, both in vivo and in vitro, is regulated by a variety of signals. These signals can be of biochemical origin, such as those from growth factors and cytokines, or from different mechanical loads, such as fluid shear stress and matrix elasticity. The mechanisms by which the mechanical loads affect precursor cell differentiation are not entirely understood, but their role in regenerative medicine and cell therapy could be of vast importance. This paper reviews the role of mechanical loads on the differentiation of precursor cells.
Collapse
Affiliation(s)
- Dalit Shav
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel.
| | | |
Collapse
|
50
|
Xenos M, Rambhia S, Alemu Y, Einav S, Ricotta JJ, Labropoulos N, Tassiopoulos A, Bluestein D. Patient based abdominal aortic aneurysm rupture risk prediction combining clinical visualizing modalities with fluid structure interaction numerical simulations. Annu Int Conf IEEE Eng Med Biol Soc 2010; 2010:5173-5176. [PMID: 21095820 DOI: 10.1109/iembs.2010.5626138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Fluid structure interaction (FSI) simulations of patient-specific fusiform non-ruptured and contained ruptured Abdominal Aortic Aneurysm (AAA) geometries were conducted. The goals were: (1) to test the ability of our FSI methodology to predict the location of rupture, by correlating the high wall stress regions with the rupture location, (2) estimate the state of the pathological condition by calculating the ruptured potential index (RPI) of the AAA and (3) predict the disease progression by comparing healthy and pathological aortas.
Collapse
Affiliation(s)
- Michalis Xenos
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-8181, USA
| | | | | | | | | | | | | | | |
Collapse
|