Surgical management of chest injuries in patients with multiple and/or severe trauma- a systematic review and clinical practice guideline update.

PURPOSE: Our aim was to update evidence-based and consensus-based recommendations for the surgical and interventional management of blunt or penetrating injuries to the chest in patients with multiple and/or severe injuries on the basis of current evidence. This guideline topic is part of the 2022 update of the German Guideline on the Treatment of Patients with Multiple and/or Severe Injuries. METHODS: MEDLINE and Embase were systematically searched to May and June 2021 respectively for the update and new questions. Further literature reports were obtained from clinical experts. Randomised controlled trials, prospective cohort studies, cross-sectional studies and comparative registry studies were included if they compared interventions for the surgical management of injuries to the chest in patients with multiple and/or severe injuries. We considered patient-relevant clinical outcomes such as mortality, length of stay, and diagnostic test accuracy. Risk of bias was assessed using NICE 2012 checklists. The evidence was synthesised narratively, and expert consensus was used to develop recommendations and determine their strength. RESULTS: One study was identified. This study compared wedge resection, lobectomy and pneumonectomy in the management of patients with severe chest trauma that required some form of lung resection. Based on the updated evidence and expert consensus, one recommendation was modified and two additional good practice points were developed. All achieved strong consensus. The recommendation on the amount of blood loss that is used as an indication for surgical intervention in patients with chest injuries was modified to reflect new findings in trauma care and patient stabilisation. The new good clinical practice points (GPPs) on the use of video-assisted thoracoscopic surgery (VATS) in patients with initial circulatory stability are also in line with current practice in patient care. CONCLUSION: As has been shown in recent decades, the treatment of chest trauma has become less and less invasive for the patient as diagnostic and technical possibilities have expanded. Examples include interventional stenting of aortic injuries, video-assisted thoracoscopy and parenchyma-sparing treatment of lung injuries. These less invasive treatment concepts reduce morbidity and mortality in the primary surgical phase following a chest trauma.

Impact of Time of Surgery on the Outcome after Surgical Stabilization of Rib Fractures in Severely Injured Patients with Severe Chest Trauma-A Matched-Pairs Analysis of the German Trauma Registry.

Purpose: In severely injured patients with multiple rib fractures, the beneficial effect of surgical stabilization is still unknown. The existing literature shows divergent results, and the indication and especially the right timing of an operation are the subject of a broad discussion. The aim of this study was to determine the influence of the time point of surgical stabilization of rib fractures (SSRF) on the outcome in a multicenter database with special regard to the duration of ventilation, intensive care, and overall hospital stay. Methods: Data from the TraumaRegister DGU collected between 2010 and 2019 were used to evaluate patients above 16 years of age with severe rib fractures [Abbreviated Injury Score (AIS) ≥ 3] who received an SSRF in a matched-pairs analysis. In this matched-pairs analysis, we compared the effects of an early SSRF within 48 h after initial trauma vs. late SSRF 3-10 days after trauma. Results: After the selection process, we were able to find 142 matched pairs for further evaluation. Early SSRF was associated with a significantly shorter length of stay in the intensive care unit (16.2 days vs. 12.7 days, p = 0.020), and the overall hospital stay (28.5 days vs. 23.4 days, p = 0.005) was significantly longer in the group with late SSRF. Concerning the days on mechanical ventilation, we were able to demonstrate a trend for an approximately 1.5 day shorter ventilation time for patients after early SSRF, although this difference was not statistically significant (p = 0.226). Conclusions: We were able to determine the significant beneficial effects of early SSRF resulting in a shorter intensive care unit stay and a shorter length of stay in hospital and additionally a trend to a shorter time on mechanical ventilation.

[Epidemiology, injury entities and treatment practice for chest wall injuries : Current scientific knowledge and treatment recommendations]. / Epidemiologie, Verletzungsentitäten und Behandlungspraxis der Thoraxwandverletzungen : Aktuelle wissenschaftliche Erkenntnisse und Therapieempfehlungen.

BACKGROUND: Fractures of the bony chest wall are common injuries. They affect almost every second severely injured person and are gaining more and more importance even after low-energy accidents, especially among older people. Complications mainly occur due to respiratory insufficiency, secondary pulmonary complications and remaining deformities with a functional disorder of the chest wall. In addition to the important conservative therapeutic measures, such as a differentiated pain therapy and pneumonia prophylaxis, operative stabilization of fractures can be an option; however, this is still controversially discussed. OBJECTIVE: A thematically structured overview provides basic knowledge on rib and sternal fractures as well as the treatment options. MATERIAL AND METHODS: Epidemiological facts are presented based on the relevant literature and clinical experience. Anatomical principles are intended to improve understanding of the various entities of rib and sternal fractures. For this purpose, the new AO­/OTA classification system is presented and finally therapeutic options including different osteosynthesis procedures are presented and their importance discussed. RESULTS AND DISCUSSION: Multimodal therapy concepts and closely controlled follow-up examinations of fractures avoid complications or can detect them early. Bony chest wall injuries should still be evaluated for complications and typical fracture patterns identified and classified. Modern osteosynthesis procedures with high patient safety and soft tissue-preserving tissue preparation for the surgical access route to the ribs and sternum provide an excellent opportunity for successful restoration of the anatomical and physiological integrity of the bony thorax.

[Injuries of the posterior and lateral chest wall-importance of an additional clavicular fracture]. / Verletzungen der posterioren und lateralen Brustwand ­ Bedeutung einer zusätzlichen Klavikulafraktur.

BACKGROUND: Flail chest wall injuries (FCI) are common in younger patients due to high-speed trauma and in older patients due to low-energy trauma or falls from a low height. They show a high incidence of concomitant injuries and are therefore associated with high morbidity and mortality. If there is also an ipsilateral clavicular fracture (CF), the outcome is significantly poorer. The skeleton of the shoulder and chest loses stability and can lead to a loss of function of the shoulder and a pronounced deformation of the chest wall. OBJECTIVE: This article shows the origin and clinical importance of FCI. What importance does a concomitant ipsilateral CF have and how can these costoclavicular injuries (CCI) be managed conservatively and operatively? MATERIAL AND METHODS: After primary emergency care of the patients with appropriate diagnostics, in the presence of CCI operative stabilization was carried out by means of locked plate osteosynthesis of the clavicle and the affected ribs via minimally invasive approaches with the patient under general anesthesia. Patients were followed up postoperatively. Various minimally invasive posterolateral approaches to the chest wall were previously performed in a corpse study and then put into practice. RESULTS AND CONCLUSION: This study presents therapeutic options for the reconstruction of the chest wall based on the established literature and clinical examples. An ipsilateral CF combined with fractures of the 2nd-4th ribs can be treated through an innovative clavipectoral approach. For the other fractures, standard approaches to the anterolateral and posterolateral chest wall are performed, which are associated with a good outcome in clinical practice. An operative stabilization should be performed at the latest when FCI or CCI together with a dislocating fracture and a marked deformation of the thoracic wall are present. Remaining misalignments are associated with a simultaneous loss of function of the chest wall and shoulder.

[Lesions of the anterior chest wall-significance of additional fractures of the spine]. / Verletzungen der anterioren Brustwand ­ Bedeutung zusätzlicher Frakturen der Wirbelsäule.

BACKGROUND: Fractures of the anterior chest wall are rare among the total number of fractures. They include sternal fractures (SF) and the adjacent cartilaginous structures of the ribs. The accident mechanism can allow conclusions to be drawn about which further accompanying injuries may be present, e.g. rib and spinal fractures. OBJECTIVE: The present work is intended to give an overview of injuries of the anterior chest wall. It includes clinical aspects as well as imaging and popular literature. MATERIAL AND METHODS: Included are injury constellations of the anterolateral chest wall, in particular of the sternum in combination with injuries of the spinal column in the sense of a sternovertebral injury (SVI). Possible treatment strategies were reviewed and the corresponding advantages and disadvantages are presented. RESULTS: In symptomatic fractures of the anterior chest wall, their operative stabilization should be considered in order to restore the stability of the trunk. In addition, rib fractures in direct trauma and spinal injuries in indirect trauma are often included in the treatment. CONCLUSION: In the case of injuries of the thoracic trunk, this must always be regarded as a unit and must therefore be clarified in the context of the clinical examination and diagnostic apparatus. The possible accident mechanism can allow conclusions to be drawn about possible injury patterns, e.g. in the sense of SVIs.

[Anesthesia, ventilation and pain treatment in thoracic trauma]. / Narkose, Beatmung und Schmerztherapie beim Thoraxtrauma.

The management of anesthesia plays a central role in the treatment of thoracic trauma, both in the initial phase when safeguarding the difficult airway and in the intensive care unit. A rapid transfer to a trauma center should be considered in order to recognize and treat organ dysfunction in time. Development of atelectasis, pneumonia and acute lung failure are common pulmonary complications. Non-invasive ventilation combined with physiotherapy and respiratory training can help to minimize these pulmonary complications. If single lung ventilation is necessary as part of the operative patient care, a double-lumen tube, a bronchial blocker and the Univent®-Tubus (Fuji Systems Corporation, Tokyo, Japan) can be used. Special attention should be paid to the hypoxic pulmonary vasoconstriction that occurs in this maneuver. Pain therapy is ideally carried out patient-adapted with epidural anesthesia. In addition, intraoperatively inserted catheters in the sense of a continuous intercostal block or serratus plane block are good alternatives. The aim of these therapies should be early mobilization and transfer of the patient to rehabilitation.

[Frequency and age distribution of combined sternovertebral injuries : Analysis of routine data from German hospitals 2005-2012]. / Häufigkeit und Altersverteilung sternovertebraler Kombinationsverletzungen : Analyse aus Routinedaten deutscher Krankenhäuser 2005­2012.

BACKGROUND: Combinations of sternal and spinal fractures often occur due to high velocity accidents and are associated with a high incidence of concomitant injuries. The anterior thoracic wall is described as the fourth column of torso stability, which is why sternovertebral injuries (SVI) present a high risk of sagittal deformation of the trunk, in particular injuries of the thoracic spine. To date, no studies have been published on the frequency distribution of the involved vertebral bodies in large patient groups. OBJECTIVES: This study was intended to elaborate a frequency distribution of vertebral fractures accompanying sternal fractures (SF) and examine the risk of a vertebral fracture accompanying a SF. MATERIAL AND METHODS: A total of 48,193 cases with the main or secondary diagnosis of a SF and 897,963 cases with vertebral fractures based on routine data of German hospitals from the years 2005-2012 were evaluated. A concomitant injury to the spinal column was examined for each vertebral body and then evaluated statistically. RESULTS AND CONCLUSIONS: Of all patients with a SF 30.96% also suffered from a vertebral fracture. Of these 3.11% were SF as the main diagnosis and 60.89% the secondary diagnosis. While vertebral fractures generally occurred most frequently in the region of the thoracolumbar transition and the second cervical vertebral body, the SVI showed a further frequency peak in the range from the lower cervical spine to the middle thoracic spine. The present study was able to show a frequency distribution of accompanying vertebral body injuries in a large and representative collective in the case of SF for the first time.

Arduino control of a pulsatile flow rig.

This note describes the design and testing of a programmable pulsatile flow pump using an Arduino micro-controller. The goal of this work is to build a compact and affordable system that can relatively easily be programmed to generate physiological waveforms. The system described here was designed to be used in an in-vitro set-up for vascular access hemodynamics research, and hence incorporates a gear pump that delivers a mean flow of 900 ml/min in a test flow loop, and a peak flow of 1106 ml/min. After a number of simple identification experiments to assess the dynamic behaviour of the system, a feed-forward control routine was implemented. The resulting system was shown to be able to produce the targeted representative waveform with less than 3.6% error. Finally, we outline how to further increase the accuracy of the system, and how to adapt it to specific user needs.

Review of Experimental Modelling in Vascular Access for Hemodialysis.

This paper reviews applications of experimental modelling in vascular access for hemodialysis. Different techniques that are used in in-vitro experiments are bulk pressure and flow rate measurements, Laser Doppler Velocimetry and Vector Doppler Ultrasound point velocity measurements, and whole-field measurements such as Particle Image Velocimetry, Ultrasound Imaging Velocimetry, Colour Doppler Ultrasound, and Planar Laser Induced Fluorescence. Of these methods, the ultrasound techniques can also be used in-vivo, to provide realistic boundary conditions to in-vitro experiments or numerical simulations. In the reviewed work, experimental modelling is mainly used to support computational models, but also in some cases as a tool on its own. It is concluded that, to further advance the utility of computational modelling in vascular access research, a rigorous verification and validation procedure should be adopted. Experimental modelling can play an important role in both in-vitro validation, and the quantification of the accuracy, uncertainty, and reproducibility of in-vivo measurement methods.

Stabilization of flail chest injuries: minimized approach techniques to treat the core of instability.

PURPOSE: Stabilizing techniques of flail chest injuries usually need wide approaches to the chest wall. Three main regions need to be considered when stabilizing the rib cage: median-anterior with dissection of pectoral muscle; lateral-axillary with dissection of musculi (mm) serratus, externus abdominis; posterior inter spinoscapular with division of mm rhomboidei, trapezius and latissimus dorsi. Severe morbidity due to these invasive approaches needs to be considered. This study discusses possibilities for minimized approaches to the shown regions. METHOD: Fifteen patients were stabilized by locked plate osteosynthesis (MatrixRib®) between May 2012 and April 2014 and prospectively followed up. Flail chest injuries were managed through limited incisions to the anterior, the lateral, and the posterior parts of the chest wall or their combinations. Each approach was 4-10 cm using Alexis® retractor. RESULTS: One minimized approach offered sufficient access at least to four ribs posterior and laterally, four pairs of ribs anterior in all cases. There was no need to divide latissimus dorsi muscle. Trapezius und rhomboid muscles were only limited divided, whereas a subcutaneous dissection of serratus and abdominis muscles was necessary. A follow-up showed sufficient consolidation. COMPLICATIONS: pneumothorax (2) and seroma (2). CONCLUSION: Minimized approaches allow sufficient stabilization of severe dislocated rib fractures without extensive dissection or division of the important muscles. Keeping the arm and, thus, the scapula mobile is very important for providing the largest reachable surface of the rib cage through each approach.

[Bony injuries of the thoracic cage in multiple trauma : Incidence, concomitant injuries, course and outcome]. / Knöcherne Verletzung der Brustwand beim Polytrauma : Inzidenz, Begleitverletzungen, Verlauf und Outcome.

BACKGROUND: Thoracic trauma is considered to be responsible for 25 % of fatalities in multiple trauma and is a frequent injury with an incidence of 50 %. In addition to organ injuries, severe injuries to the bony parts of the thorax also occur and these injuries are described very differently mostly based on single center data. OBJECTIVES: The focus of this study was on a holistic presentation of the prevalence and the incidence of thoracic trauma in patients with multiple trauma from the data of the large collective of the TraumaRegister DGU® (TR-DGU) with the objective of an analysis of concomitant injuries, therapy options and outcome parameters. MATERIAL AND METHODS: A retrospective analysis was carried out based on the data set of the TR-DGU from the years 2009-2013. Inclusion criteria were an injury severity scale (ISS) score ≥ 16 and primary admission to a trauma center but isolated craniocerebral injury was an exclusion criterium. Patients were separated into two groups: those with rib fractures (RF) and those with flail chest (FC). RESULTS: A total of 21,741 patients met the inclusion criteria including 10,474 (48.2 %) suffering from either RF or FC. The mean age was 49.8 ± 19.9 years in the RF group and 54.1 ± 18.2 years in the FC group. Approximately 25 % were female in both groups, 98.1 % were blunt force injuries and the median ISS was 28.0 ± 11.2 in RF and 35.1 ± 14.2 in FC. Shock, insertion of a chest tube, (multi) organ failure and fatality rates were significantly higher in the FC group as were concomitant thoracic injuries, such as pneumothorax and hemothorax. Sternal fractures without rib fractures were less common (3.8 %) than concomitant in the RF (10.1 %) and FC (14 %) groups, as were concomitant fractures of the clavicle and the scapula. Out of all patients 32.6 % showed fractures of the thoracolumbar spine, 26.5 % without rib fractures, 36.6-38.6 % with rib fractures or monolateral FC and 48.6 % concomitant to bilateral FC. Thoracotomy was carried out only in isolated cases in RF and in 10.2 % of the FC group. Operative stabilization of the thoracic cage was carried out in 3.9-9.1 % of patients in the RF group and in 17.9-23.9 % in the FC group.

[Essential measures for prehospital treatment of severely injured patients: The trauma care bundle]. / Wesentliche Maßnahmen zur prähospitalen Versorgung schwerverletzter Patienten: Das Trauma Care Bundle.

BACKGROUND: In order to ensure adequate treatment and to avoid complications, care bundles are increasingly being implemented. These are comprehensive and evidence-based procedures for the treatment of individual diseases or injuries which should be carried out for every patient. The aim of this study was to define a care bundle for the prehospital treatment of severely injured patients. MATERIAL AND METHODS: The scientific contents of the bundle were gathered from the interdisciplinary evidence-based S3 guidelines for the treatment of severely injured patients by the German Trauma Society. The ABCDE scheme suggested by the prehospital trauma life support (PHTLS®) and the advanced trauma life support (ATLS®) functioned as a matrix for the individual elements in the bundles. The identified elements were finalized by a consensus process. RESULTS AND DISCUSSION: A bundle of six elements was suggested and a comprehensive summary of key items during prehospital management of severely injured patients was identified. In a next step the effectiveness of the care bundle should be evaluated in a clinical trial.

[Use of negative pressure wound therapy on surgical incisions (prevena™) after surgery of pectus deformities reduces wound complications]. / Einsatz einer präventiven, epikutanen Unterdrucktherapie (Prevena™) bei offener Korrektur von Deformitäten der vorderen Brustwand reduziert das Auftreten von Wundheilungsstörungen.

INTRODUCTION: Pectus surgery can lead to postoperative wound complications in some cases. The purpose of this study is to determine whether preventive negative pressure wound therapy (NPWT) could reduce wound complications after open pectus surgery. MATERIAL AND METHODS: 100 patients after open procedure for the treatment of pectus excavatum or pectus carinatum in the years 2010 to 2012 were retrospectively analysed. 50 patients treated with Prevena™ (KCI Medical Products GmbH, Wiesbaden, Germany) were compared with 50 patients whose wounds were covered with OPSITE® film (Smith & Nephew, Hamburg, Germany). Wound closure was performed following a standard procedure as well as the placement of subcutaneous drains. Therefore two comparable groups of patients were formed and analysed by standardised parameters. The wound dressing was placed epicutaneously immediately after wound closure in the operating room and removed after 5 days in each case. Follow-ups were performed immediately after removal of the wound dressing, at the time of discharge from hospital as well as 6 and 12 weeks after operation. The wounds were checked for tenderness, pain, secretion, redness and fistulas. RESULTS: The Prevena group showed 10 % wound complications which needed operative treatment, whereas the OPSITE group showed complications in 24 %. Some patients who were treated with Prevena showed superficial skin lesions at the rim of the foam and the film. All of these lesions healed well. CONCLUSION: Treating wounds postoperatively with preventive measures (NPWT) showed a remarkable reduction of wound complications following open pectus surgery whereas statistically the difference was not significant (p = 0.074).

Advancement of physical process by mental activation: a prospective controlled study.

According to the literature, patients who are significantly impaired by physical mobility limitations can be rehabilitated if the patient's working memory is used to capacity. The conclusion that periodic mental activity improves physical rehabilitation should be evaluated. This is a prospective, controlled, and randomized open study of patients who underwent a total hip arthroplasty (THA). Sixteen patients who played the video game Dr. Kawashima's Brain Training: How Old Is Your Brain? were compared in terms of rehabilitation progress to 16 individuals who did not play. Harris Hip and Merle d'Aubigné scores were evaluated 1 d preoperation and again 12 +/- 1 d postoperation. Preoperation, no significant differences in hip scores between the gaming and control groups were found (median Harris Hip score: 39 vs 33, respectively, p = 0.304; median Merle D'Aubigné score: 12 vs 9, respectively, p = 0.254). Postoperation, there were significant differences between the gaming and control groups (median Harris Hip score: 76.0 vs 56.5, respectively, p = 0.001; median Merle D'Aubigné score: 16.0 vs 13.5, respectively, p = 0.014). Within both groups, the posttest scores significantly improved; however, the increase for the gaming group was greater for both measures. Because the influence of age, sex, and level of education can be excluded, it can be assumed that mental activities can improve physical rehabilitation after THA.

Induction of the skin endogenous protective mitochondrial MnSOD by Vitreoscilla filiformis extract.

Vitreoscilla filiformis (Vf), a filamentous bacteria living in fresh water is thought to contribute to the observed beneficial effects of Spa water on skin. An active fraction obtained from a Vf biomass was evaluated for its ability to modulate mRNA expression in cultured skin cells. cDNA array analysis was conducted first using a customized membrane including 1176 selected and fully identified genes involved in skin physiology and homeostasis then the newly developed full genome U133 plus 2.0 GeneChip from Affymetrix. The mitochondrial protective manganese superoxide dismutase (MnSOD/SOD-2) was identified as a preferentially induced mRNA target in both normal human dermal fibroblasts and keratinocytes. Induction at the transcriptional level in both cell types was confirmed using quantitative real time/polymerase chain reaction and a kinetic analysis revealed a maximal increase in mRNA expression 20 h after stimulation with Vf extract (Vfe). Using immunofluorescent (fluorescent cell sorter) analysis, an induction of MnSOD protein in both normal human dermal skin fibroblasts (x1.6; P < 0.01) and epidermal keratinocytes (x1.4; P < 0.01) was confirmed. As MnSOD is a major inducible free-radical scavenger in skin, these results suggest that the Vfe could induce skin cells to produce their own endogenous protective defences in vivo against both exogenous environmental stressors such as UV irradiation or microflora as well as to combat endogenous sources of deleterious free radicals involved in skin ageing. Finally, in order to confirm the in vivo potential of this original extract in human, we evaluated its protective activity vs. placebo on the generation of sunburn cells in epidermis under UVB stress. As expected from in vitro profiling, Vfe was indeed found to significantly inhibit the appearance of sunburn cells in UVB-exposed areas, a signature of skin alteration which has been suggested to be linked to a defect in MnSOD protective activity. Altogether, those data suggest that the combination of a suitable protective UV filter together with this bioactive Vfe might improve skin protection through complementary pathways.

Ultrasensitive quartz crystal microbalance sensors for detection of M13-Phages in liquids.

Quartz crystal microbalance (QCM) sensors are widely used for determining liquid properties or probing interfacial processes. For some applications the sensitivity of the QCM sensors typically used (5-20 MHz) is limited compared with other biosensor methods. In this study ultrasensitive QCM sensors with resonant frequencies from 39 to 110 MHz for measurements in the liquid phase are presented. The fundamental sensor effect of a QCM is the decrease of the resonant frequency of an oscillating quartz crystal due to the binding of mass on a coated surface during the measurement. The sensitivity of QCM sensors increases strongly with an increasing resonant frequency and, therefore, with a decreasing thickness of the sensitive area. The new kind of ultrasensitive QCM sensors used in this study is based on chemically milled shear mode quartz crystals which are etched only in the center of the blank, forming a thin quartz membrane with a thick, mechanically stable outer ring. An immunoassay using a virus specific monoclonal antibody and a M13-Phage showed an increase in the signal to noise ratio by a factor of more than 6 for 56 MHz quartz crystals compared with standard 19 MHz quartz crystals, the detection limit was improved by a factor of 200. Probing of acoustic properties of glycerol/water mixtures resulted in an increase in sensitivity, which is in very good agreement with theory. Chemically milled QCM sensors strongly improve the sensitivity in biosensing and probing of acoustic properties and, therefore, offer interesting new application fields for QCM sensors.

Protein detection with a novel ISFET-based zeta potential analyzer.

This publication presents a novel ISFET-based measurement concept for the determination of the zeta potential, which is known to be an efficient method for the detection of protein accumulations onto surfaces. The basic set-up consists of two monolithically integrated ISFET sensors arranged in a serial flow configuration together with a precoated fused silica capillary, which provides the reactive surface for the protein detection. In comparison with the state of the art, this novel biosensor system is characterized by a small size, an extremely low reagent consumption, a simple fluidic concept, a short analysis time, and a very effective noise suppression due to the differential ISFET set-up. In the following, an overview is given over the theoretical background of the measurement principle. In order to get deeper insight into the theoretical background of the measurement principle, a simulation model was developed which is based on the site-binding theory and takes into account the different proton dissociation equilibria of the surface groups as well as the influence of monovalent electrolyte ions. A quasi-Newton iteration after Broyden was used for the numerical solution of the formulated equation system. For an experimental confirmation of the simulation results, the calculated zeta potential vs. pH curves were compared with measured data for various modifications of the fused silica capillaries (in untreated state, after a hydrothermal activation, and after the deposition of several silanes) and it could be shown, that the chosen physical model represents a satifactory theoretical basis for the description of the occuring surface effects. Measurements before and after a covalent coupling of the model analyte lysozyme were performed in order to demonstrate the feasibility of an immunosensor based on the measurement of the streaming potential and showed a significant shift of the zeta potential vs. pH curves.

Characterization of immobilization methods for African swine fever virus protein and antibodies with a piezoelectric immunosensor.

A direct piezoelectric flow injection analysis immunoassay for the detection of African Swine Fever virus and antibodies is presented. The peptide-specific monoclonal antibody 18BG3 and the virus protein 73 were used for detection with a quartz crystal microbalance. Accumulation of the analyte on the surface of this mass-sensitive biosensor resulted in a shift of the resonant frequency. Highly selective receptor layers were applied on the sensing electrode of the quartz crystal for detection of the complementary analyte. Different immobilization methods proved to be appropriate for coating of the monoclonal antibody 18BG3. A quartz crystal covalently coated with the antibody 18BG3 detected virus protein VP73 samples more than 20 times and was stable for more than 30 days. The coating of virus protein was performed by physisorption. A sensor with a virus protein receptor layer detected antibody 18BG3 samples 10 times within one day. The sensor device was able to perform one measurement cycle including blocking and regeneration within 30 min. With the help of a suitable carrier liquid, measurements with serum samples were performed. The calibration curves for measurements in buffer and in serum could be determined and the detection limits for virus protein detection were 0.31 and 1 microgram/ml, and for antibody detection 0.1 and 0.2 microgram/ml, respectively.

Topical ointment therapy benefits premature infants.

OBJECTIVE: Premature infants have an ineffective epidermal barrier. The aim of this study was to investigate the cutaneous and systemic effects of preservative-free topical ointment therapy in premature infants. STUDY DESIGN: We conducted a prospective, randomized study of 60 infants less than 33 weeks' estimated gestational age. The treated infants received therapy for 2 weeks with twice-daily preservative-free topical ointment therapy while the control group received no topical treatment or as-needed therapy with a water-in-oil emollient. Data collection included transepidermal water loss (TEWL) measurement, skin condition evaluations, fungal and quantitative bacterial skin cultures, analysis of fluid requirements, patterns of weight low or gain, and the incidence of blood and cerebrospinal fluid cultures positive for microorganisms. RESULTS: We found that topical ointment therapy significantly decreased TEWL during the first 6 hours after the initial application. TEWL was decreased by 67% (p = 0.0001) when measured 30 minutes after application and 34% (p = 0.001) when measured 4 to 6 hours after application. We also observed significantly superior skin condition scores in the treated group on study days 7 and 14 (p = 0.001) and 0.0004, respectively). Quantitative bacterial cultures revealed significantly less colonization of the axilla on day 2, 3, or 4 and on day 14 (p = 0.008 and 0.04, respectively). The incidence of positive findings in blood and/or cerebrospinal fluid cultures was 3.3% in the treated group of infants versus 26.7% in the control group (p = 0.02). There was no statistical difference in the fluid requirements or patterns of weight gain or loss during the 2 weeks of the study. CONCLUSIONS: Preservative-free topical ointment therapy decreased TEWL for 6 hours after application, decreased the severity of dermatitis, and decreased bacterial colonization of axillary skin. Infants treated with ointment had fewer blood and cerebrospinal fluid cultures positive for microorganisms. These data support the use of topical ointment therapy in very premature infants during the first weeks after birth.