Search

In a prospective observational pilot study on patients undergoing elective cardiac surgery with cardiopulmonary bypass, we evaluated label-free quantitative phase imaging (QPI) with digital holographic microscopy (DHM) to describe perioperative inflammation by changes in biophysical cell properties of lymphocytes and monocytes. Blood samples from 25 patients were investigated prior to cardiac surgery and postoperatively at day 1, 3 and 6. Biophysical and morphological cell parameters accessible with DHM, such as cell volume, refractive index, dry mass, and cell shape related form factor, were acquired and compared to common flow cytometric blood cell markers of inflammation and selected routine laboratory parameters. In all examined patients, cardiac surgery induced an acute inflammatory response as indicated by changes in routine laboratory parameters and flow cytometric cell markers. DHM results were associated with routine laboratory and flow cytometric data and correlated with complications in the postoperative course. In a subgroup analysis, patients were classified according to the inflammation related C-reactive protein (CRP) level, treatment with epinephrine and the occurrence of postoperative complications. Patients with regular courses, without epinephrine treatment and with low CRP values showed a postoperative lymphocyte volume increase. In contrast, the group of patients with increased CRP levels indicated an even further enlarged lymphocyte volume, while for the groups of epinephrine treated patients and patients with complicative courses, no postoperative lymphocyte volume changes were detected. In summary, the study demonstrates the capability of DHM to describe biophysical cell parameters of perioperative lymphocytes and monocytes changes in cardiac surgery patients. The pattern of correlations between biophysical DHM data and laboratory parameters, flow cytometric cell markers, and the postoperative course exemplify DHM as a promising diagnostic tool for a characterization of inflammatory processes and course of disease.

In a prospective observational pilot study, we evaluated label-free quantitative phase imaging (QPI) by digital holographic microscopy (DHM) as tool to describe perioperative changes in biophysical cell properties of lymphocytes and monocytes after cardiac surgery.

In a prospective observational pilot study on patients undergoing elective cardiac surgery with cardiopulmonary bypass, we evaluated label-free quantitative phase imaging (QPI) with digital holographic microscopy (DHM) to describe perioperative inflammation by changes in biophysical cell properties of lymphocytes and monocytes. Blood samples from 25 patients were investigated prior to cardiac surgery and postoperatively at day 1, 3 and 6. Biophysical and morphological cell parameters accessible with DHM, such as cell volume, refractive index, dry mass, and cell shape related form factor, were acquired and compared to common flow cytometric blood cell markers of inflammation and selected routine laboratory parameters. In all examined patients, cardiac surgery induced an acute inflammatory response as indicated by changes in routine laboratory parameters and flow cytometric cell markers. DHM results were associated with routine laboratory and flow cytometric data and correlated with complications in the postoperative course. In a subgroup analysis, patients were classified according to the inflammation related C-reactive protein (CRP) level, treatment with epinephrine and the occurrence of postoperative complications. Patients with regular courses, without epinephrine treatment and with low CRP values showed a postoperative lymphocyte volume increase. In contrast, the group of patients with increased CRP levels indicated an even further enlarged lymphocyte volume, while for the groups of epinephrine treated patients and patients with complicative courses, no postoperative lymphocyte volume changes were detected. In summary, the study demonstrates the capability of DHM to describe biophysical cell parameters of perioperative lymphocytes and monocytes changes in cardiac surgery patients. The pattern of correlations between biophysical DHM data and laboratory parameters, flow cytometric cell markers, and the postoperative course exemplify DHM as a promising diagnostic tool for a characterization of inflammatory processes and course of disease.

Background The endothelial glycocalyx (eGC) covers the luminal surface of the vascular endothelium and plays an important protective role in systemic inflammatory states and particularly in sepsis. Its breakdown leads to capillary leak and organ dysfunction. Moreover, sepsis-induced alterations of sublingual microcirculation are associated with a worse clinical outcome. The present study was performed to investigate the associations between eGC dimensions and established parameters of microcirculation dysfunction in sepsis. Methods This observational, prospective, cross-sectional study included 40 participants, of which 30 critically ill septic patients were recruited from intensive care units of a university hospital and 10 healthy volunteers served as controls. The established microcirculation parameters were obtained sublingually and analyzed according to the current recommendations. In addition, the perfused boundary region (PBR), an inverse parameter of the eGC dimensions, was measured sublingually, using novel data acquisition and analysis software (GlycoCheck™). Moreover, we exposed living endothelial cells to 5% serum from a subgroup of study participants, and the delta eGC breakdown, measured with atomic force microscopy (AFM), was correlated with the paired PBR values. Results In septic patients, sublingual microcirculation was impaired, as indicated by a reduced microvascular flow index (MFI) and a reduced proportion of perfused vessels (PPV) compared to those in healthy controls (MFI, 2.93 vs 2.74, p = 0.002; PPV, 98.53 vs 92.58, p = 0.0004). PBR values were significantly higher in septic patients compared to those in healthy controls, indicating damage of the eGC (2.04 vs 2.34, p

Bei vielen intensivmedizinischen Erkrankungen tritt eine Storung der Mikrozirkulation auf, die bisher noch nicht routinemasig untersucht werden kann. Fur Therapieentscheidungen und Prognoseeinschatzung wurde eine Information uber die Mikrozirkulation bei kritisch kranken Patienten jedoch von grosem Interesse sein. Die optische Koharenztomographie-Angiographie (OCTA) ermoglicht es, nichtinvasiv, kontaktlos und schnell den Blutfluss in der Mikrozirkulation der Retina darzustellen und hat daher moglicherweise das Potenzial, Storungen der Mikrozirkulation bei kritisch kranken Patienten zu diagnostizieren. Folgende Fragestellungen werden betrachtet: Stellenwert der Mikrozirkulation in der Intensivmedizin, Gegenuberstellung der Methoden der Videomikroskopie und der OCTA, Analyse der praklinischen und klinischen Daten zum Einsatz der OCTA bei intensivmedizinischen Krankheitsbildern. Es erfolgte eine selektive Literaturrecherche und Analyse der Daten. Eine direkte Darstellung der Mikrozirkulation ist seit Jahren mithilfe der Videomikroskopie moglich, im klinischen Alltag aber aufgrund der Storanfalligkeit und zeitaufwendigen Auswertung nicht etabliert. Die OCTA ist ein nichtinvasives und kontaktloses Verfahren zur Darstellung des retinalen Blutflusses. Die OCTA als nichtinvasives Verfahren ist eine vielversprechende Messmethode, die eine bettseitige Analyse der Mikrozirkulation bei kritisch kranken Patienten zukunftig ermoglichen konnte. Hierzu sind allerdings noch einige technische Einschrankungen zu uberwinden.

INTRODUCTION The conjunctival region may serve as an alternative site for microcirculatory measurements. The present study was performed to investigate the correlation of sublingual and conjunctival microcirculation in ovine models of septic and hemorrhagic shock. METHODS Septic shock was induced in 10 sheep by inoculation of feces into the peritoneal cavity until mean arterial pressure (MAP) was

OBJECTIVES Propofol-based sedation may increase hemodynamic instability by decreasing vascular tone and venous return. Incremental exogenous catecholamines doses may be required to counteract such effects, aggravating the deleterious effects of sympathetic overstimulation. α-2 adrenergic agonists have been reported to decrease norepinephrine requirements in experimental septic shock. The aim of the present study is to test the hypothesis that switching from sedation with propofol to the α-2 agonist dexmedetomidine may decrease norepinephrine doses in septic shock. DESIGN Prospective open-label crossover study. SETTINGS University hospital, ICU. PATIENTS Thirty-eight septic shock patients requiring norepinephrine to maintain adequate mean arterial pressure and needing deep sedation with propofol and remifentanil to maintain a Richmond Agitation-Sedation Scale score between -3 and -4. INTERVENTIONS An initial set of measurements including hemodynamics, norepinephrine doses, and depth of sedation were obtained during sedation with propofol. Propofol was then replaced by dexmedetomidine and a second set of data was obtained after 4 hours of dexmedetomidine infusion. Sedation was switched back to propofol, and a final set of measurements was obtained after 8 hours. A Richmond Agitation-Sedation Scale score between -3 and -4 was maintained during the study period. MEASUREMENTS AND MAIN RESULTS Norepinephrine requirements decreased from 0.69 ± 0.72 μg/kg/min before dexmedetomidine to 0.30 ± 0.25 μg/kg/min 4 hours after dexmedetomidine infusion, increasing again to 0.42 ± 0.36 μg/kg/min while on propofol 8 hours after stopping dexmedetomidine (p < 0.005). Dexmedetomidine dosage was 0.7 ± 0.2 μg/kg/hr. Before and after dexmedetomidine infusion, sedative doses remained unchanged (propofol 2.6 ± 1.2 vs 2.6 ± 1.2 mg/kg/hr; p = 0.23 and remifentanil 1.27 ± 0.17 vs 1.27 ± 0.16 μg/kg/hr; p = 0.52, respectively). Richmond Agitation-Sedation Scale was -4 (-4 to -3) before, -4 (-4 to -3) during, and -4 (-4 to -4) after dexmedetomidine (p = 0.07). CONCLUSIONS For a comparable level of sedation, switching from propofol to dexmedetomidine resulted in a reduction of catecholamine requirements in septic shock patients.

Background Simulation has become integral to the training of both undergraduate medical students and medical professionals. Due to the increasing degree of realism and range of features, the latest mannequins are referred to as high-fidelity simulators. Whether increased realism leads to a general improvement in trainees’ outcomes is currently controversial and there are few data on the effects of these simulators on participants’ personal confidence and self-assessment. Methods One-hundred-and-thirty-five fourth-year medical students were randomly allocated to participate in either a high- or a low-fidelity simulated Advanced Life Support training session. Theoretical knowledge and self-assessment pre- and post-tests were completed. Students’ performance in simulated scenarios was recorded and rated by experts. Results Participants in both groups showed a significant improvement in theoretical knowledge in the post-test as compared to the pre-test, without significant intergroup differences. Performance, as assessed by video analysis, was comparable between groups, but, unexpectedly, the low-fidelity group had significantly better results in several sub-items. Irrespective of the findings, participants of the high-fidelity group considered themselves to be advantaged, solely based on their group allocation, compared with those in the low-fidelity group, at both pre- and post-self-assessments. Self-rated confidence regarding their individual performance was also significantly overrated. Conclusion The use of high-fidelity simulation led to equal or even worse performance and growth in knowledge as compared to low-fidelity simulation, while also inducing undesirable effects such as overconfidence. Hence, in this study, it was not beneficial compared to low-fidelity, but rather proved to be an adverse learning tool.

Microcirculatory disorders are crucial in pathophysiology of organ dysfunction in critical illness. Evaluation of sublingual microcirculation is not routinely conducted in daily practice due to time-consuming analysis and susceptibility to artifacts. We investigated the suitability of optical coherence tomography angiography (OCTA) for contactless evaluation of sublingual microcirculation. Sublingual microcirculation was imaged in 10 healthy volunteers, using an OCTA device and an incident dark field (IDF) illumination microscopy (current gold standard). OCTA images were analyzed with regard to flow density and perfused vessel density (PVDbyOCTA). IDF videos were analyzed following current recommendations. Flow density was automatically extracted from OCTA images (whole en face 48.9% [43.2; 54.5]; central ring 52.6% [43.6; 60.6]). PVDbyOCTA did not differ from the PVD calculated from IDF videos (PVDbyOCTA 18.6 mm/mm² [18.0; 21.7]) vs. PVDbyIDF 21.0 mm/mm² [17.5; 22.9]; p = 0.430). Analysis according to Bland-Altman revealed a mean bias of 0.95 mm/mm² (95% Confidence interval −1.34 to 3.25) between PVDbyOCTA and PVDbyIDF with limits of agreement of −5.34 to 7.24 mm/mm². This study is the first to demonstrate the suitability of OCTA for evaluating sublingual microcirculation. Comparison of the perfused vessel density between methods showed a plausible level of agreement.

Background To determine the distribution of vancomycin into the cerebrospinal fluid (CSF) in patients with external ventricular drain (EVD)-associated ventriculitis, the pharmacokinetics of vancomycin were evaluated, and covariate relationships explored. Methods For the population pharmacokinetic model patients were recruited in a neuro-critical care unit at the University Hospital of Muenster in the period between January 2014 and June 2015. All patients had a clinical evidence of (EVD)-associated ventriculitis. Population pharmacokinetic analysis of vancomycin was performed using NONMEM®. Results A total of 184 blood and 133 CSF samples were collected from 29 patients. The final population pharmacokinetic model is a three-compartment model with linear elimination. Creatinine clearance (ClCr ) and CSF-lactate were detected as significant covariates, showing that the total vancomycin plasma clearance (Cl) depends on ClCr and furthermore, the clearance (Cldif ) between the central and CSF compartment correlates with CSF lactate concentration. Based on the final model, the following values were estimated by NONMEM®: Cl = 5.15 L/h, Q (intercompartmental clearance) =3.31L/h, Cldif = 0.0031 L/h, Vcentral = 42.1 L, VCSF = 0.32 L and the value of Vperipheral was fixed to 86.2 L. With the developed pharmacokinetic model, AUC (area under the curve) values as well as CSF trough levels were simulated. Conclusion Based on our analysis, the dosing of vancomycin should be referred to the degree of inflammation (derived from the CSF lactate concentration) and renal function (derived from ClCr ).

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New Background Fluid resuscitation in hemorrhagic shock aims to restore hemodynamics and repair altered microcirculation. Hemodynamic coherence is the concordant performance of macro- and microcirculation. The present study on fluid therapy in hemorrhagic shock hypothesized that the choice of fluid (0.9% sodium chloride [saline group] or balanced 6% hydroxyethyl starch 130/0.4 [hydroxyethyl starch group]) impacts on hemodynamic coherence. Methods After instrumentation, 10 sheep were bled up to 30 ml/kg body weight of blood stopping at a mean arterial pressure of 30 mmHg to establish hemorrhagic shock. To reestablish baseline mean arterial pressure, they received either saline or hydroxyethyl starch (each n = 5). Hemodynamic coherence was assessed by comparison of changes in mean arterial pressure and both perfused vessel density and microvascular flow index. Results Bleeding of 23 ml/kg blood [21; 30] (median [25th; 75th percentile]) in the saline group and 24 ml/kg [22; 25] (P = 0.916) in the hydroxyethyl starch group led to hemorrhagic shock. Fluid resuscitation reestablished baseline mean arterial pressure in all sheep of the hydroxyethyl starch group and in one sheep of the saline group. In the saline group 4,980 ml [3,312; 5,700] and in the hydroxyethyl starch group 610 ml [489; 615] of fluid were needed (P = 0.009). In hemorrhagic shock perfused vessel density (saline from 100% to 83% [49; 86]; hydroxyethyl starch from 100% to 74% [61; 80]) and microvascular flow index (saline from 3.1 [2.5; 3.3] to 2.0 [1.6; 2.3]; hydroxyethyl starch from 2.9 [2.9; 3.1] to 2.5 [2.3; 2.7]) decreased in both groups. After resuscitation both variables improved in the hydroxyethyl starch group (perfused vessel density: 125% [120; 147]; microvascular flow index: 3.4 [3.2; 3.5]), whereas in the saline group perfused vessel density further decreased (64% [62; 79]) and microvascular flow index increased less than in the hydroxyethyl starch group (2.7 [2.4; 2.8]; both P < 0.001 for saline vs. hydroxyethyl starch). Conclusions Resuscitation with hydroxyethyl starch maintained coherence in hemorrhagic shock. In contrast, saline only improved macro- but not microcirculation. Hemodynamic coherence might be influenced by the choice of resuscitation fluid.

Objectives Results from end-of-course student evaluations of teaching (SETs) are taken seriously by faculties and form part of a decision base for the recruitment of academic staff, the distribution of funds and changes to curricula. However, there is some doubt as to whether these evaluation instruments accurately measure the quality of course content, teaching and knowledge transfer. We investigated whether the provision of chocolate cookies as a content-unrelated intervention influences SET results. Methods We performed a randomised controlled trial in the setting of a curricular emergency medicine course. Participants were 118 third-year medical students. Participants were randomly allocated into 20 groups, 10 of which had free access to 500 g of chocolate cookies during an emergency medicine course session (cookie group) and 10 of which did not (control group). All groups were taught by the same teachers. Educational content and course material were the same for both groups. After the course, all students were asked to complete a 38-question evaluation form. Results A total of 112 students completed the evaluation form. The cookie group evaluated teachers significantly better than the control group (113.4 ± 4.9 versus 109.2 ± 7.3; p = 0.001, effect size 0.68). Course material was considered better (10.1 ± 2.3 versus 8.4 ± 2.8; p = 0.001, effect size 0.66) and summation scores evaluating the course overall were significantly higher (224.5 ± 12.5 versus 217.2 ± 16.1; p = 0.008, effect size 0.51) in the cookie group. Conclusions The provision of chocolate cookies had a significant effect on course evaluation. These findings question the validity of SETs and their use in making widespread decisions within a faculty.

There is increasing evidence in the literature that preoperative treatment with levosimendan optimizes cardiopulmonary haemodynamics in patients scheduled for the implantation of a Left Ventricular Assist Device (LVAD). The present case report describes changes in sublingual microcirculation using incident dark field video microscopy in a patient, who received a continuous infusion of 0.5 mg/h levosimendan 12 h before LVAD implantation. Despite no evident macrohaemodynamic or metabolic changes, there was a dramatic reduction in total vessel density and perfused vessel density suggesting a deterioration of microcirculation according to the consensus conference criteria in vessels smaller than 20 μm in diameter. However, the microcirculation of all visible vessels (regardless of diameter) was maintained. This potential misinterpretation is explained by a levosimedan-induced vasodilation and the subsequent reduction of the percentage of vessels with a diameter smaller than 20 μm. Physicians should carefully consider this pitfall of applying the consensus conference criteria in vasodilator-treated patients.

The present review initially describes the rationale for the use of non-adrenergic vasopressors in the treatment of distributive shock and then provides an overview of the individual vasopressin-receptor agonists, namely arginine vasopressin, terlipressin, and selepressin. Following a brief summary of their current use in clinical practice, the present review focuses on the influence of vasopressin-receptor agonists on macro- and microvascular coupling, also referred to as hemodynamic coherence. On the basis of the current evidence from experimental and clinical studies, vasopressin-receptor agonists do not negatively influence macro- and microvascular coupling as compared to the standard therapy with norepinephrine, when used in established treatment regimes. A higher selectivity for the V 1a -receptor seems to be beneficial; however, future clinical trials are warranted to verify this assumption. Notably, the optimal treatment regime for non-adrenergic vasopressors with respect to compound, dose, and timing still needs to be defined.

Many critically ill patients show a disturbance of the microcirculation, which is not yet regularly examined in the clinical routine; however, for treatment decisions and estimation of the prognosis it would be important to obtain detailed information about the microcirculation in critically ill patients. Optical coherence tomography angiography (OCTA) is a non-invasive, contact-free technique, which enables visualization of the blood flow in the retinal microcirculation within a few seconds. Therefore, it may have the potential to diagnose microcirculation disorders in critically ill patients.The aims of the study were to assess the importance of the microcirculation in intensive care medicine, a comparison of the methods of video microscopy and OCTA and analysis of preclinical and clinical data on the use of OCTA in intensive care medicine.A selective literature review and data analysis were carried out.A direct visualization of the microcirculation has been possible for many years with the technique of video microscopy but this has not become established in the clinical routine due to the susceptibility to interferences and a time-consuming manual analysis. The OCTA is a non-invasive and contact-free method for the visualization of retinal blood flow. First preclinical data in septic and hemorrhagic shock show good results of OCTA for analysis of the microcirculation.The non-invasive technique of OCTA is a promising measurement method to enable bedside analysis of the microcirculation in critically ill paients in the future; however, some technical limitations must still be overcome.

Background This study aimed to investigate the feasibility of optical coherence tomography angiography (OCT-A) for quantitative analysis of flow density to assess changes in retinal perfusion in an experimental model of haemorrhagic shock. Methods Haemorrhagic shock was induced in five healthy, anaesthetized sheep by stepwise blood withdrawal of 3 × 10 ml∙kg− 1 body weight. OCT-A imaging of retinal perfusion was performed using an OCT device. Incident dark-field illumination microscopy videos were obtained for the evaluation of conjunctival microcirculation. Haemodynamic variables and flow density data in the OCT angiogram were analysed before and during progressive haemorrhage resulting in haemorrhagic shock as well as after fluid resuscitation with 10 ml∙kg− 1 body weight of balanced hydroxyethyl starch solution (6% HES 130/0.4). Videos of the conjunctival microcirculation were recorded at baseline, in haemorrhagic shock, and after resuscitation. Data are presented as median with interquartile range. Comparisons between time points were made using Friedman’s test and the degree of correlation between two variables was expressed as Spearman’s rank correlation coefficient. Results Mean arterial pressure and cardiac index (CI) decreased and lactate concentration increased after induction of shock, and haemodynamics recovered after resuscitation. The flow density in the superficial retinal OCT angiogram decreased significantly after shock induction (baseline 44.7% (40.3; 50.5) vs haemorrhagic shock 34.5% (32.8; 40.4); P = 0.027) and recovered after fluid resuscitation (46.9% (41.7; 50.7) vs haemorrhagic shock; P = 0.027). The proportion of perfused vessels of the conjunctival microcirculation showed similar changes. The flow density measured using OCT-A correlated with the conjunctival microcirculation (perfused vessel density: Spearman’s rank correlation coefficient ρ = 0.750, P = 0.001) and haemodynamic parameters (CI: ρ = 0.693, P

BACKGROUND Potassium-(K)-channel inhibitors may increase systemic vascular resistance in vasodilatory shock states. OBJECTIVE The purpose of the present study was to compare the macro- and microvascular effects of the adenosine triphosphate-sensitive K-channel-(KATP)-inhibitor glipizide and the nonselective K-channel inhibitor tetraethylammonium (TEA) in ovine endotoxemic shock and septic shock in rats. DESIGN Two randomized, controlled laboratory studies. ANIMALS Thirty female sheep and 40 male Sprague Dawley rats. SETTING Animal research facility INTERVENTION:: Systemic hemodynamics were analyzed in ovine endotoxemic shock with guideline-oriented supportive therapy. Sheep were allocated to three treatment groups for 12 h: glipizide 10 mg kg·h, TEA 8 mg kg·h, or 0.9% saline. The microvascular effects of each drug were evaluated in septic rats (cecal ligation and puncture model) receiving a 2-h infusion of each study drug: glipizide 20 mg kg·h; TEA 50 mg kg·h, or 0.9% saline, respectively, followed by intravital microscopy of villi microcirculation. RESULTS Compared with the control group, glipizide infusion increased systemic vascular resistance index and decreased cardiac index and heart rate (HR) in sheep (P

Objective: The aim of the current study was to compare a newly developed web-based freely accessible software program for manual analysis of the microcirculation, the Capillary Mapper (CM), with AVA 3.2 software (AVA; MicroVision Medical B.V., Amsterdam, The Netherlands), which is the current gold standard for analysis of microcirculation videos. Methods: A web-based software program was developed, which enables manual analysis of videos of the microcirculation to be carried out according to recommendations of the 2018 consensus conference. A set of 50 high quality microcirculation videos was analyzed with AVA and CM with respect to total vessel density, perfused vessel density, proportion of perfused vessels, and the microvascular flow index. Results: Comparison of the mean values derived from manual analysis with CM and AVA revealed no significant differences in microcirculatory variables. Analysis according to Bland and Altman revealed an acceptable bias between manual analysis with the CM and AVA for all variables tested with sufficient limits of agreement. The analysis of intraclass correlation showed “excellent” agreement for all microcirculatory variables analyzed. Conclusions: The newly developed CM was successfully validated for manual analyses of microcirculation videos against the current gold standard, the software AVA 3.2.

The Surviving Sepsis Guidelines suggest the use of vasopressin in case of catecholamine-refractory septic shock. Terlipressin (TP) as a V1-selective AVP analogue is a potential alternative, though data regarding the first-line administration in septic shock are scarce. The present study explored and compared the effects of first-line vs. second-line infusion of TP or sole norepinephrine regarding organ function, fluid and norepinephrine requirements and survival in fulminant ovine septic shock. Peritoneal sepsis was induced in 23 ewes after laparotomy and faecal withdrawal from the caecum. After onset of shock, causal and supportive sepsis therapy (antibiotics, peritoneal lavage, fluids and open-label norepinephrine) was performed in all animals. Concurrently, animals were randomized to receive 0.9% sodium chloride (control group) or TP (2 µg∙kg−1∙h−1, first-line group) after shock onset. In the second-line TP group, TP (2 µg∙kg−1∙h−1) was started once norepinephrine requirements exceeded 0.5 µg∙kg−1∙min−1. No significant differences were found between groups regarding survival, haemodynamics as well as fluid- and catecholamine-requirements. Kidney function and electron microscopic kidney injury were comparable between groups. In the present model of fulminant ovine septic shock, first-line TP infusion had no significant effect on fluid and norepinephrine requirements or organ dysfunction as compared to second-line TP infusion or placebo.

Als zentraler Venendruck (ZVD) wird der Druck in der oberen Hohlvene (V. cava superior) sowie im rechten Vorhof bezeichnet. Dieser entspricht annahernd dem Fullungsdruck des rechten Ventrikels. Der ZVDwird auf Intensivstationen in der Regel mit einem invasiven Messverfahren bestimmt. Wird der ZVD zur Beurteilung pathologischer Zustande herangezogen, muss bedacht werden, dass multiple Faktoren Einfluss auf ihn ausuben (z.B. Funktion des rechten Ventrikels, Flussigkeitshaushalt, intrathorakale Druckverhaltnisse und Venentonus) [1]. In den zuruckliegenden Jahren wurde eine teils emotionale Diskussion uber die Bedeutung des ZVD als Surrogatparameter der Vorlast oder zur Beurteilung der Volumenreagibilitat gefuhrt [2–4]. Diese Diskussion hat dazu gefuhrt, dass der Parameter ZVD selbst unter Druck geraten ist und sein Image gelitten hat. Vorausgesetzt der ZVD wird korrekt bestimmt, kann man durch die Messung des ZVD bzw. die Beurteilung der Druckkurve jedoch auch heute noch relevante Informationen uber den Patienten gewinnen, unabhangig von seiner Eignung als Parameter der Volumenreagibilitat. Die vorliegende Ubersichtsarbeit diskutiert anhand der aktuellen Evidenz den Stellenwert des ZVD in der Intensivmedizin. Die Bestimmung des zentralen Venendrucks

The international, multicentre, double-blinded, randomized, controlled ATHOS-3 trial by Khanna and colleagues (1) was conducted from May 2015 to January 2017 in nine countries across Europe, North America, and Australia. ATHOS-3 was designed to answer two primary endpoints within a study period of 48 h.

Background Life-threatening diseases of critically ill patients are known to derange microcirculation. Automatic analysis of microcirculation would provide a bedside diagnostic tool for microcirculatory disorders and allow immediate therapeutic decisions based upon microcirculation analysis. Methods After induction of general anaesthesia and instrumentation for haemodynamic monitoring, haemorrhagic shock was induced in ten female sheep by stepwise blood withdrawal of 3 × 10 mL per kilogram body weight. Before and after the induction of haemorrhagic shock, haemodynamic variables, samples for blood gas analysis, and videos of conjunctival microcirculation were obtained by incident dark field illumination microscopy. Microcirculatory videos were analysed (1) manually with AVA software version 3.2 by an experienced user and (2) automatically by AVA software version 4.2 for total vessel density (TVD), perfused vessel density (PVD) and proportion of perfused vessels (PPV). Correlation between the two analysis methods was examined by intraclass correlation coefficient and Bland-Altman analysis. Results The induction of haemorrhagic shock decreased the mean arterial pressure (from 87 ± 11 to 40 ± 7 mmHg; p

Objective To provide physiological data and reference values in awake and anaesthetized sheep aged 6–12 months. Study design Descriptive study. Animals Data from 260 female sheep of the species Ovis orientalis aries aged 6–12 months were extracted from 10 experimental trials. Methods Data from pulmonary arterial thermodilution in awake (cohort 1; n = 109) and anaesthetized animals (cohort 2; n = 81), and transpulmonary thermodilution in anaesthetized animals (cohort 3; n = 70) were analysed. General anaesthesia was induced by intramuscular injection of S-ketamine and midazolam and maintained by inhaled isoflurane. Standard laboratory variables (blood gas and clinical chemistry) were assessed. Results A total of 7553 single data entries from 260 healthy sheep were included. Measurement errors or invalid data documentation meant that 313 data entries (4.1%) were excluded. A small confidence interval for median values was calculated for nearly all variables. The median body weight was 39.8 kg (2.5–97.5th percentile 30.6–48.1 kg). A set of reference values (2.5–97.5th percentiles) is provided for common cardiopulmonary and laboratory variables. Compared to awake animals, haemodynamic variables were markedly influenced by anaesthesia, as reflected by a considerably lower stroke volume index in anaesthetized sheep. There were also differences in stroke volume index between the cohorts of pulmonary artery and transpulmonary thermodilution. Conclusions and clinical relevance The present work presents a large and consistent database of a variety of physiological variables measured in healthy juvenile female sheep. The data appear to be robust and allow the establishment of standardized inclusion criteria for experimental studies and may help to better evaluate past, present and future research. Differences between pulmonary artery and transpulmonary thermodilution should be assessed in future studies.