Once excess liquid gains access to air spaces of an injured lung, the act of breathing creates and destroys foam and thereby contributes to the wounding of epithelial cells by interfacial stress. Since cells are not elastic continua, but rather complex network structures composed of solid as well as liquid elements, we hypothesize that plasma membrane (PM) wounding is preceded by a phase separation, which results in blebbing. We postulate that interventions such as a hypertonic treatment increase adhesive PM-cytoskeletal (CSK) interactions, thereby preventing blebbing as well as PM wounds. We formed PM tethers in alveolar epithelial cells and fibroblasts and measured their retractive force as readout of PM-CSK adhesive interactions using optical tweezers. A 50-mOsm increase in media osmolarity consistently increased the tether retractive force in epithelial cells but lowered it in fibroblasts. The osmo-response was abolished by pretreatment with latrunculin, cytochalasin D, and calcium chelation. Epithelial cells and fibroblasts were exposed to interfacial stress in a microchannel, and the fraction of wounded cells were measured. Interventions that increased PM-CSK adhesive interactions prevented blebbing and were cytoprotective regardless of cell type. Finally, we exposed ex vivo perfused rat lungs to injurious mechanical ventilation and showed that hypertonic conditioning reduced the number of wounded subpleural alveolus resident cells to baseline levels. Our observations support the hypothesis that PM-CSK adhesive interactions are important determinants of the cellular response to deforming stress and pave the way for preclinical efficacy trials of hypertonic treatment in experimental models of acute lung injury. alveolar epithelial cell; acute lung injury; interfacial stress; osmotic response; cytoprotection THE SYNDROME OF ventilator-induced lung injury (VILI) contributes to the morbidity and mortality of critically ill patients (25). The clinical manifestations of the syndrome are indistinguishable from those of all-cause acute lung injury and at their core reflect a mechanotransduction event, i.e., the effects of deforming stress on cell and tissue injury, remodeling, and repair. The complex topographical distributions of lung mechanical properties, and hence of parenchymal stress and strain together with the numerous and nuanced injury manifestations, make it very difficult to establish mechanistic cause and effect relationships on the scale of interest, e.g., that of individual cells. Our research, therefore, focuses on a very specific mechanotransduction event, namely physical stress-related epithelial cell wounding and repair, which we believe contributes to the pathogenesis VILI.In the current study, we present a body of work in which we have explored the effects of hypertonic exposure on cell wounding in experimental models ranging from individual cells to rodent VILI preparations. The experiments were not designed to test the preclinical efficacy of an intervention, but rather to explore a cell bio...

Background: Vasoplegic syndrome is associated with increased morbidity and mortality in patients undergoing cardiac surgery. This retrospective, single-center study aimed to evaluate the effect of early use of methylene blue (MB) on hemodynamics after an intraoperative diagnosis of vasoplegic syndrome (VS). Methods: Over a 10-year period, all patients diagnosed with intraoperative VS (hypotension despite treatment with norepinephrine ≥0.3 μg/kg/min and vasopressin ≥1 IE/h) while undergoing heart surgery and cardiopulmonary bypass were identified, and their data were examined. The intervention group received MB (2 mg/kg intravenous) within 15 min after the diagnosis of vasoplegia, while the control group received standard therapy. The two groups were matched using propensity scores. Results: Of the 1022 patients identified with VS, 221 received MB intraoperatively, and among them, 60 patients received MB within 15 min after the diagnosis of VS. After early MB application, mean arterial pressure was significantly higher, and vasopressor support was significantly lower within the first hour (p = 0.015) after the diagnosis of vasoplegia, resulting in a lower cumulative amount of norepinephrine (p = 0.018) and vasopressin (p = 0.003). The intraoperative need of fresh frozen plasma in the intervention group was lower compared to the control group (p = 0.015). Additionally, the intervention group had higher creatinine values in the first three postoperative days (p = 0.036) without changes in dialysis incidence. The 90-day survival did not differ significantly (p = 0.270). Conclusion: Our results indicate the additive effects of MB use during VS compared to standard vasopressor therapy only. Early MB administration for VS may significantly improve the patients’ hemodynamics with minor side effects.

Background. Several anesthesiologic regimens can be used for open radical retropubic prostatectomy. The aim of this retrospective analysis was to compare the combined general epidural anesthesia and the combined spinal epidural anesthesia with regard to availability, efficacy, side effects, and perioperative time consumption in a high-volume center. Methods. A retrospective analysis was performed by querying the electronic medical records of 1207 consecutive patients from the database of our online documentation software. All patients underwent open radical retropubic prostatectomy from 01/2008 to 08/2011 and met the study criteria. Linear and multivariate regression analyses were performed to identify differences in parameters such as time consumption in the operating unit, hemodynamic parameters, volume replacement, and catecholamine therapy. Results. 698 (57.8%) patients have been undergoing open radical retropubic prostatectomy under combined spinal epidural anesthesia and 509 (42.2%) patients by combined general epidural anesthesia. Operating unit (p <0.0001) and post-anesthesia care unit stay (p <0.0001) as well as total hospital stay (p <0.0001) were significantly shorter in the combined spinal epidural anesthesia group. In addition, this group had reduced intraoperative volume need (p <0.0001) as well as lower need of catecholamines (p <0.0001). Conclusions. This retrospective study suggests that the combined spinal epidural anesthesia seems to be a suitable and efficient anesthesia technique for patients undergoing open radical retropubic prostatectomy. This specific approach reduces time in the operation unit and length of hospital stay.