A Concept for Extending the Applicability of Constraint-Induced Movement Therapy through Motor Cortex Activity Feedback Using a Neural Prosthesis

This paper describes a concept for the extension of constraint-induced movement therapy (CIMT) through the use of feedback of primary motor cortex activity. CIMT requires residual movement to act as a source of feedback to the patient, thus preventing its application to those with no perceptible movement. It is proposed in this paper that it is possible to provide feedback of the motor cortex effort to the patient by measurement with near infrared spectroscopy (NIRS). Significant changes in such effort may be used to drive rehabilitative robotic actuators, for example. This may provide a possible avenue for extending CIMT to patients hitherto excluded as a result of severity of condition. In support of such a paradigm, this paper details the current status of CIMT and related attempts to extend rehabilitation therapy through the application of technology. An introduction to the relevant haemodynamics is given including a description of the basic technology behind a suitable NIRS system. An illustration of the proposed therapy is described using a simple NIRS system driving a robotic arm during simple upper-limb unilateral isometric contraction exercises with healthy subjects

Front Lines of Thoracic Surgery

Front Lines of Thoracic Surgery collects up-to-date contributions on some of the most debated topics in today's clinical practice of cardiac, aortic, and general thoracic surgery,and anesthesia as viewed by authors personally involved in their evolution. The strong and genuine enthusiasm of the authors was clearly perceptible in all their contributions and I'm sure that will further stimulate the reader to understand their messages. Moreover, the strict adhesion of the authors' original observations and findings to the evidence base proves that facts are the best guarantee of scientific value. This is not a standard textbook where the whole discipline is organically presented, but authors' contributions are simply listed in their pertaining subclasses of Thoracic Surgery. I'm sure that this original and very promising editorial format which has and free availability at its core further increases this book's value and it will be of interest to healthcare professionals and scientists dedicated to this field

Severe re‐expansion pulmonary edema after conventional cardiac surgery: Identification and management

Re‐expansion Pulmonary Edema (REPE) is a recognized but rare complication of lung re‐inflation after pathologic collapse or intentional deflation. The presentation of REPE may be highly variable, ranging from a clinically asymptomatic, incidental radiologic finding to acute respiratory failure accompanied by severe, life‐threatening hypoxemia. With the current report, we present a patient with severe aortic insufficiency, severe mitral regurgitation, coronary artery disease, pulmonary hypertension, who underwent aortic valve replacement, mitral valvuloplasty, coronary artery bypass grafting, and developed at the immediate post‐ operative period severe respiratory failure due to REPE, requiring venous‐venous Extracorporeal Membrane Oxygenation (VV‐ECMO).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149568/1/jocs14057.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149568/2/jocs14057_am.pd

Point-of-care tissue oxygenation assessment with SnapshotNIR for alloplastic and autologous breast reconstruction

UNLABELLED: In breast reconstruction, mastectomy and free flaps are susceptible to vascular compromise and tissue necrosis. The SnapshotNIR device (Kent Imaging, Calgary, AB, Canada) utilizes near-infrared spectroscopy to measure tissue oxygen saturation (StO METHODS: Patients receiving immediate alloplastic reconstruction after mastectomy or autologous reconstruction were enrolled. Preoperative, intraoperative, and postoperative images were taken of the flaps. StO RESULTS: Thirty-two breasts underwent alloplastic reconstruction; 38 breasts underwent autologous reconstruction. No enrollees developed skin necrosis. StO CONCLUSIONS: The SnapshotNIR device detected normal spatial and temporal differences in tissue oxygenation over the operative course of alloplastic and autologous breast reconstruction. A multi-institutional, prospective clinical trial is needed to determine the sensitivity and specificity of this device for detecting skin flap necrosis

A Prospective study of Analysing Predictive Factors for Major Lower Extremity Amputations in Diabetic Foot Infection

INTRODUCTION: Diabetic foot is a most common entity in developing nations. Amputation due to diabetic foot infection adds up burden to an individual as well as to the economy of the country. And there is no separate criteria for detecting early unsalvageable limb. BACKGROUND: The aim of the study is to formulate a scoring system to detect early unsalvageable diabetic foot in order to provide critical care, and also to study about the common microbial organisms that complicate diabetic foot infections, and their antibiotic sensitivity patterns. METHODS: This is a prospective observational study which was carried out in 120patients who admitted with diabetic foot infections in GRH MADURAI for a period of 18months, and they were observed for gangrene, pulse status, ABI, infection patterns, osteomyelitis, Hb%, total wbc count, ESR, CRP, lipid profile and cardiac status at the time of admission. A scoring system was devised using these parameters. RESULTS: Out of these parameters - gangrene, pulse status, infections, osteomyelitis, ABI were found to be major contributory factors and hemoglobin, duration of diabetes, total wbc count, CRP, cardiac status, ESR, lipid profile were found to be minor contributory/predictive factors. In these scoring system patients with scores 13and below were managed by conservative procedures, and with 14 to 17 went for minor amputation and scores 18 and above went for major amputations. CONCLUSION: By using our scoring system we can separate the patient who is more likely to go for amputations as early as possible, and we can provide an early apt intervention to save his/her limb

Mechanische Kreislaufunterstützung bei Patienten im akuten kardiogenen Shock

Objectives Cardiogenic shock (CS) as the final stage of Heart failure (HF) is present in approximately 25% of cases and is associated with high mortality. Temporary mechanical circulatory support (MCS) is widely used for CS therapy. In our research, we investigated and compared different temporary MCS concepts based on microaxial intraaortic impeller pumps. Methods The data of all patients who received MCS with a temporary microaxial left ventricular impeller pump in the German Heart Center Berlin (DHZB) since 01/2016 were collected retrospectively and used for a database establishment. The obtained data were analyzed in regard to different clinical aspects and published. This dissertation summarizes and describes the results of three major publications. Results The results of the pilot study demonstrated a 43% survival in 28 patients on isolated impeller pump support, as well as 44% in 9 CS patients on combination of v a ECLS and Impella. Preoperative cardiopulmonary resuscitation (CPR) and an arterial pH 7.45 were associated with poor outcomes. In the second study, 70 patients were supported with Impella 5.0/5.5®. The overall 30 day survival was 51%. An increase in arterial lactate (OR 1.217 per 1 mmol/L; p=0.015) and CPR before implantation (OR 16.74; p=0.009) were identified as predictors of 30 day mortality on Impella support. A cut-off of 8 mmol/L for preoperative lactate showed a specificity of 0.944 and a sensitivity of 0.294 (OR 7.083, CI 1.422 35.28; p=0.017) for 30 day mortality. Based on these data, an algorithm for optimal short-term MCS therapy was developed and thereafter applied as a standardized operational procedure at the DHZB. In my third analysis we compared the percutaneously implanted Impella CP® and larger surgical Impella 5.0/5.5®. In unadjusted cohorts the 30 day survival was significantly higher in the Impella 5.0/5.5® group (58% vs. 36%, p=0.021). After propensity score adjustment for relevant preoperative demographic and hemodynamic parameters, the 30 day survival was similar between the groups (OR 1.23, 95% CI [0.34-4.18], p=0.744). Preoperative lactate levels above 8 mmol/L and CPR before implantation were associated with poor outcomes in both cohorts (OR 10.7, 95% CI [3.45-47.34], p<0.001; OR 13.2, 95% CI [4.28-57.89], p<0.001). Based on these results the selection algorithm from the second study was amended to include the use of percutaneous impeller pumps. Conclusions A total of 203 patients treated with different MCS devices were analyzed. Our studies demonstrated that temporary MCS with microaxial impeller pumps is a feasible treatment in CS patients. In cases with preoperative CPR or lactate levels ≥ 8 mmol/L an advanced treatment concept with a combination of Impella and v a ECLS should be pursued. An algorithm based on these parameters may prove useful for optimal patient selection and to identify optimal temporary MCS in CS patients.Ziele Kardiogener Schock (KS) als Endstadium der Herzinsuffizienz (HI) tritt in ungefähr 25% der Fälle auf und ist mit einer hohen Sterblichkeit assoziiert. Temporäre mechanische Kreislaufunterstützung (MKU) wird in der Therapie des KS eigesetzt. In unseren Studien wurden verschiedene Konzepte für temporäre MKU auf der Basis der mikroaxialen int-raaortalen Impellerpumpe untersucht und verglichen. Methoden Die Daten von allen im Deutschen Herzzentrum Berlin (DHZB) seit 01/2016 zur mecha-nischen Kreislaufunterstützung mit einem temporären linksventrikulären mikroaxialen Impellersystem versorgten Patienten*innen wurden retrospektiv in einer Datenbank ge-sammelt, analysiert und publiziert. Diese Dissertation ist eine Zusammenfassung der Ergebnisse der drei wichtigsten Pub-likationen. Ergebnisse Die Ergebnisse der Pilotstudie zeigten ein Überleben von 43% bei 28 Patienten*innen unter isolierter mikroaxialer Impellerpumpentherapie, sowie 44% bei 9 Patienten*innen mit Kombination von v-a ECLS und Impella. Präoperative kardiopulmonale Reanimati-on (KPR) sowie ein arterieller pH 7,45 waren mit einem schlechteren Überleben assoziiert. In der zweiten Studie wurden 70 Patienten*innen isoliert mit Impella 5.0/5.5® behandelt. Das 30-Tage-Überleben betrug 51%. Ein präoperativer Anstieg des arteriellen Laktatwertes (OR 1.217 pro 1 mmol/l; p=0.015) sowie KPR (OR 16.74; p=0.009) wurden als Prädiktoren für die 30-Tage-Mortalität identifiziert. Ein arterielles Laktat von 8 mmol/l wies hierbei eine Spezifität von 0.944 und eine Sensitivität von 0.294 (OR 7.083, CI 1.422–35.28; p=0.017). Auf der Basis dieser Daten wurde ein Algorithmus für die Behandlung des KS mittels temporärer MKU entwickelt und folglich im DHZB im Rahmen einer SOP festgelegt. In meiner dritten Analyse haben wir die perkutan implantierbaren Impella CP und die größeren chirurgischen Impella 5.0/5.5® Systeme verglichen. Das nicht adjustierte 30-Tage-Überleben war signifikant höher in der Impella 5.0/5.5® Kohorte (58% vs. 36%, p=0.021). Nach der Propensity-Score-Adjustierung waren die Kohorten ähnlich (OR 1.23, 95% CI [0.34-4.18], p=0.744). Ein präoperativer Laktatwert über 8 mmol/L sowie präoperative KPR gingen mit einer erhöhten Mortalität einher (OR 10.7, 95% CI [3.45-47.34], p<0.001; OR 13.2, 95% CI [4.28-57.89], p<0.001). Der Algorithmus aus der zweiten Studie wurde auf der Basis neuer Ergebnisse um die Anwendung der perkutan implantierbaren Impellerpumpen erweitert. Schlussfolgerung Insgesamt wurden von mir 203 Patienten*innen mit verschiedenen MKU-Systemen ana-lysiert. Unsere Studien haben gezeigt, dass mikroaxiale Impellerpumpen eine effektive Therapie im KS darstellen. Präoperative KPR sowie Laktatwerte ≥ 8 mmol/L sollten eine erweiterte Therapie bestehend aus einer Kombination von einer Impellerpumpe und v-a ECLS nach sich ziehen. Ein Algorithmus basierend auf diesen Erkenntnissen kann helfen eine optimale temporäre MKU-Therapie auszuwählen

Biomechanics of pressure ulcer in body tissues interacting with external forces during locomotion

2009-2010 > Academic research: refereed > Publication in refereed journalAuthor’s OriginalPublishe

Expression of miRNA-210 in human bone marrow-derived mesenchymal stromal cells under oxygen deprivation

A major limitation in the development of efficient clinical protocols for mesenchymal stromal cell (MStroC)-based tissue regeneration therapy is the low retention and survival of MStroC in injured tissue after therapeutic administration. Low oxygen concentration preconditioning (LOP) during ex vivo cultivation of MStroC, as a method for mimicking oxygenation in their physiological microenvironment, has been shown to be beneficial in clinical trials using MStroC. Introducing hypoxia-mimicking molecules into MStroC during cultivation could be an advantageous LOP strategy. MicroRNA (miRNA) drugs are good candidates for this approach. Analysis of the expression of miRNA-210 in human bone marrow-derived MStroC in conditions of acute and extended hypoxia (24 to 72 h) was performed using RT-qPCR methodology. HIF-1 alpha and HIF-2 alpha gene knockdown cell lines were generated using lentiviral transduction of short hairpin RNA (shRNA) in order to examine whether miRNA-210 expression is regulated by transcription factor HIF-1 and/or HIF-2. We detected a significant increase in miRNA-210 expression in hypoxic conditions at time points of 24, 48 and 72 h (p lt 0.05). Knocking down of HIF-1 alpha and HIF-2 alpha genes indicated involvement of both transcription factors in the elevation of miRNA-210 expression. These results point to miRNA-210 as a good candidate for a hypoxia-mimicking molecule in LOP strategy

NONINVASIVE MULTIMODAL DIFFUSE OPTICAL IMAGING OF VULNERABLE TISSUE HEMODYNAMICS

Measurement of tissue hemodynamics provides vital information for the assessment of tissue viability. This thesis reports three noninvasive near-infrared diffuse optical systems for spectroscopic measurements and tomographic imaging of tissue hemodynamics in vulnerable tissues with the goal of disease diagnosis and treatment monitoring. A hybrid near-infrared spectroscopy/diffuse correlation spectroscopy (NIRS/DCS) instrument with a contact fiber-optic probe was developed and utilized for simultaneous and continuous monitoring of blood flow (BF), blood oxygenation, and oxidative metabolism in exercising gastrocnemius. Results measured by the hybrid NIRS/DCS instrument in 37 subjects (mean age: 67 ± 6) indicated that vitamin D supplement plus aerobic training improved muscle metabolic function in older population. To reduce the interference and potential infection risk on vulnerable tissues caused by the contact measurement, a noncontact diffuse correlation spectroscopy/tomography (ncDCS/ncDCT) system was then developed. The ncDCS/ncDCT system employed optical lenses to project limited numbers of sources and detectors on the tissue surface. A motor-driven noncontact probe scanned over a region of interest to collect boundary data for three dimensional (3D) tomographic imaging of blood flow distribution. The ncDCS was tested for BF measurements in mastectomy skin flaps. Nineteen (19) patients underwent mastectomy and implant-based breast reconstruction were measured before and immediately after mastectomy. The BF index after mastectomy in each patient was normalized to its baseline value before surgery to get relative BF (rBF). Since rBF values in the patients with necrosis (n = 4) were significantly lower than those without necrosis (n = 15), rBF levels can be used to predict mastectomy skin flap necrosis. The ncDCT was tested for 3D imaging of BF distributions in chronic wounds of 5 patients. Spatial variations in BF contrasts over the wounded tissues were observed, indicating the capability of ncDCT in detecting tissue hemodynamic heterogeneities. To improve temporal/spatial resolution and avoid motion artifacts due to a long mechanical scanning of ncDCT, an electron-multiplying charge-coupled device based noncontact speckle contrast diffuse correlation tomography (scDCT) was developed. Validation of scDCT was done by imaging both high and low BF contrasts in tissue-like phantoms and human forearms. In a wound imaging study using scDCT, significant lower BF values were observed in the burned areas/volumes compared to surrounding normal tissues in two patients with burn. One limitation in this study was the potential influence of other unknown tissue optical properties such as tissue absorption coefficient (µa) on BF measurements. A new algorithm was then developed to extract both µa and BF using light intensities and speckle contrasts measured by scDCT at multiple source-detector distances. The new algorithm was validated using tissue-like liquid phantoms with varied values of µa and BF index. In-vivo validation and application of the innovative scDCT technique with the new algorithm is the subject of future work