Cardiac Depression in Pigs after Multiple Trauma - Characterization of Posttraumatic Structural and Functional Alterations

The purpose of this study was to define the relationship between cardiac depression and morphological and immunological alterations in cardiac tissue after multiple trauma. However, the mechanistic basis of depressed cardiac function after trauma is still elusive. In a porcine polytrauma model including blunt chest trauma, liver laceration, femur fracture and haemorrhage serial trans-thoracic echocardiography was performed and correlated with cellular cardiac injury as well as with the occurrence of extracellular histones in serum. Postmortem analysis of heart tissue was performed 72 h after trauma. Ejection fraction and shortening fraction of the left ventricle were significantly impaired between 4 and 27 h after trauma. H-FABP, troponin I and extracellular histones were elevated early after trauma and returned to baseline after 24 and 48 h, respectively. Furthermore, increased nitrotyrosine and Il-1β generation and apoptosis were identified in cardiac tissue after trauma. Main structural findings revealed alteration of connexin 43 (Cx43) and co-translocation of Cx43 and zonula occludens 1 to the cytosol, reduction of α-actinin and increase of desmin in cardiomyocytes after trauma. The cellular and subcellular events demonstrated in this report may for the first time explain molecular mechanisms associated with cardiac dysfunction after multiple trauma.

Characterization of blunt chest trauma in a long-term porcine model of severe multiple trauma

Chest trauma has a significant relevance on outcome after severe trauma. Clinically, impaired lung function typically occurs within 72 hours after trauma. However, the underlying pathophysiological mechanisms are still not fully elucidated. Therefore, we aimed to establish an experimental long-term model to investigate physiological, morphologic and inflammatory changes, after severe trauma. Male pigs (sus scrofa) sustained severe trauma (including unilateral chest trauma, femur fracture, liver laceration and hemorrhagic shock). Additionally, non-injured animals served as sham controls. Chest trauma resulted in severe lung damage on both CT and histological analyses. Furthermore, severe inflammation with a systemic increase of IL-6 (p = 0.0305) and a local increase of IL-8 in BAL (p = 0.0009) was observed. The pO₂/FiO₂ ratio in trauma animals decreased over the observation period (p < 0.0001) but not in the sham group (p = 0.2967). Electrical Impedance Tomography (EIT) revealed differences between the traumatized and healthy lung (p < 0.0001). In conclusion, a clinically relevant, long-term model of blunt chest trauma with concomitant injuries has been developed. This reproducible model allows to examine local and systemic consequences of trauma and is valid for investigation of potential diagnostic or therapeutic options. In this context, EIT might represent a radiation-free method for bedside diagnostics.

Molecular weight and molar substitution are more important in HES-induced renal impairment than concentration after hemorrhagic and septic shock

BACKGROUND

Clinical studies have raised concerns about the safety of 6% hydroxyethylstarch (HES) 130/0.42, but the pathomechanisms of this renal impairment remain unknown. To evaluate the effects of different HES concentrations, molar substitutions and molecular weights in HES-induced renal impairment, we used a porcine two-hit model that combined haemorrhagic and septic shock.

METHODS

We conducted a prospective, randomised, double-blinded, controlled study in a university animal laboratory. Thirty anaesthetised and ventilated pigs were randomised to receive volume replacement therapy using 6% HES130/0.42, 6% HES200/0.5, 10% HES130/0.42 or 10% HES200/0.5, all dissolved in 0.9% NaCl rather than 0.9% NaCl alone. First, we bled the animals until they reached half of their baseline mean arterial pressure (MAP) for 45 minutes followed by fluid resuscitation. As a second hit, sepsis was induced using an Escherichia coli-laden clot 6 hours after haemorrhagic shock. Volume resuscitation started with a delay of two hours and a central venous pressure goal of 12 mmHg.

RESULTS

At the end of the study, the groups showed no difference in cardiac output or MAP, but the volume balance (mL/kg BW) was significantly higher in the 0.9% NaCl group (346±90; P≤0.05) than in the other groups (6% HES130, 125±26; 6% HES200, 105±15; 10% HES130, 114±17; 10% HES200, 96±23). Creatinine clearance (mL/min) was significantly lower in the 6% HES200 (26±33) and 10% HES200 (15±18) groups compared to the 0.9% NaCl group (104±46; P≤0.05) but not in the HES 130 formulations (6% HES130: 64±51; 10% HES130: 58±38) at the end of the study.

CONCLUSION

In this porcine two-hit shock model, treatment with 0.9% NaCl, HES 130/0.42 or HES 200/0.5 led to a similar maintenance of haemodynamic values. Despite this similar maintenance of the haemodynamic values, volume replacement with 6% and 10% HES 200/0.5 led to an accumulation of HES, higher colloid osmotic pressure and significantly reduced renal function after haemorrhagic and septic shock. These facts support the presumption that not the concentration but the degree of substitution and the molecular weight play a decisive role in HES-induced renal impairment.

Age and growth of round goby Neogobius melanostomus associated with depth and habitat in the western basin of Lake Erie

Round goby Neogobius melanostomus were examined from the Bass Islands area in the western basin of Lake Erie, U.S.A., to determine age and growth correlations. A total of 188 specimens were collected and examined during summer 2011 with 90 aged using scale analysis. Fish were grouped by sex, depth of habitat and habitat type (anthropogenically modified shallows, natural shallows and open lake deep water). Fish ranged from 17 to 117 mm total length (L_T ) and 0+ to 3+ years. Males dominated the population (1·94:1) and backcalculated age showed that both sexes grew exponentially, with male growth rate increasing faster than female. Males were significantly larger than females in L_T and mass (both P < 0·001). The relative mass index (W_r ) was low for the sampled population (mean ± s.d. = 32·00 ± 26·87 g), implying that the health of the Bass Island area population is very poor when compared with the species throughout its range. This could be due to a lack of food resources related to population size or that the fish is not optimally utilizing the available food resources. In contradiction to these findings, regression slope coefficient (b), calculated using Fulton's condition factor (K) (mean ± s.d. =1·50 ± 0·20), was very low for each habitat, implying a healthy population throughout. This seemingly opposite effect may be due to more individuals per unit area in shallow waters, which would cause increased competition for resources. Poor condition may indicate that the Lake Erie population has reached saturation or may reflect indirect fitness costs associated with increasing anoxic or hypoxic hypolimnion conditions.

Performance of a new pulse contour method for continuous cardiac output monitoring: validation in critically ill patients

BACKGROUND

A new calibrated pulse wave analysis method (VolumeView™/EV1000™, Edwards Lifesciences, Irvine, CA, USA) has been developed to continuously monitor cardiac output (CO). The aim of this study was to compare the performance of the VolumeView method, and of the PiCCO2™ pulse contour method (Pulsion Medical Systems, Munich, Germany), with reference transpulmonary thermodilution (TPTD) CO measurements.

METHODS

This was a prospective, multicentre observational study performed in the surgical and interdisciplinary intensive care units of four tertiary hospitals. Seventy-two critically ill patients were monitored with a central venous catheter, and a thermistor-tipped femoral arterial VolumeView™ catheter connected to the EV1000™ monitor. After initial calibration by TPTD CO was continuously assessed using the VolumeView-CCO software (CCO(VolumeView)) during a 72 h period. TPTD was performed in order to obtain reference CO values (COREF). TPTD and arterial wave signals were transmitted to a PiCCO2™ monitor in order to obtain CCO(PiCCO) values. CCO(VolumeView) and CCO(PiCCO) were recorded over a 5 min interval before assessment of CO(TPTD). Bland-Altman analysis, %(errors), and concordance (trend analysis) were calculated.

RESULTS

A total of 338 matched sets of data were available for comparison. Bias for CCO(VolumeView)-CO(REF) was -0.07 litre min(-1) and for CCO(PiCCO)-CO(REF) +0.03 litre min(-1). Corresponding limits of agreement were 2.00 and 2.48 litre min(-1) (P<0.01), %(errors) 29 and 37%, respectively. Trending capabilities were comparable for both techniques.

CONCLUSIONS

The performance of the new VolumeView™-CCO method is as reliable as the PiCCO2™-CCO pulse wave analysis in critically ill patients. However, an improved precision was observed with the VolumeView™ technique. CLINICALTRIALS.GOV IDENTIFIER: NCT01405040.

A local-scale in situ approach for stressor identification of biologically impaired aquatic systems

We propose a formal causal evaluation inference process that uses a local-scale in situ approach and provides statistically defensible correlative conclusions for the biological impairment in 303(d)-listed water bodies. Fish assemblage, water chemistry, and aquatic habitat data from 66 locations in the Limberlost watershed, Indiana, were collected in August 2003 to evaluate the condition of the watershed. Anthropogenic stressors were identified from a numerical classification analysis of fish assemblage data using a biological integrity response gradient. Physical and chemical stressors were evaluated relative to the biological integrity response gradient using the Kruskal Wallis analysis of variance by ranks test. Three water chemistry variables (sodium, chloride, and barium) were associated with biological integrity. The percent run habitat, channel morphology score, and Qualitative Habitat Evaluation Index score varied with the degree of dredging. We observed a negative response between the number of species and the biological integrity gradient and a positive response with the percent tolerant individuals. This local-scale in situ approach to physical and chemical data analysis, combined with concurrent biological data collection, provided correlative relations to the impaired condition with localized environmental stressors.

Assessment of injury to fish and wildlife resources in the Grand Calumet River and Indiana Harbor Area of Concern, USA

This article is the second in a series of three that describes the results of a Natural Resource Damage Assessment (NRDA) conducted in the Grand Calumet River and Indiana Harbor Area of Concern (IHAOC). The assessment area is located in northwest Indiana and was divided into nine reaches to facilitate the assessment. This component of the NRDA was undertaken to determine if fish and wildlife resources have been injured due to exposure to contaminants that are associated with discharges of oil or releases of other hazardous substances. To support this assessment, information was compiled on the chemical composition of sediment and tissues; on the toxicity of whole sediments, pore water, and elutriates to fish; on the status of fish communities; and on fish health. The data on each of these indicators were compared to regionally relevant benchmarks to assess the presence and extent of injury to fish and wildlife resources. The results of this assessment indicate that injury to fish and wildlife resources has occurred throughout the assessment area, with up to five distinct lines of evidence demonstrating injury within the various reaches. Based on the frequency of exceedance of the benchmarks for assessing sediment and tissue chemistry data, total polychlorinated biphenyls is the primary bioaccumulative contaminant of concern in the assessment area. It is important to note, however, that this assessment was restricted by the availability of published bioaccumulation-based sediment quality guidelines, tissue residue guidelines, and other benchmarks of sediment quality conditions. The availability of chemistry data for tissues also restricted this assessment in certain reaches of the assessment area. Furthermore, insufficient information was located to facilitate identification of the substances that are causing or substantially contributing to effects on fish (i.e., sediment toxicity, impaired fish health, or impaired fish community structure). Therefore, substances not included on the list of COCs cannot necessarily be considered to be of low priority with respect to sediment injury (e.g., metals, polycyclic aromatic hydrocarbons, alkanes, alkenes, organochlorine pesticides, phthalates, dioxins, and furans, etc.).

An assessment of injury to sediments and sediment-dwelling organisms in the Grand Calumet River and Indiana Harbor Area of Concern, USA

This article is the first in a series of three that describe the results of a Natural Resource Damage Assessment (NRDA) conducted in the Grand Calumet River and Indiana Harbor Area of Concern (IHAOC). The assessment area is located in northwest Indiana and was divided into nine reaches to facilitate the assessment. This component of the NRDA was undertaken to determine if sediments and sediment-dwelling organisms have been injured due to exposure to contaminants that have accumulated in sediments as a result of discharges of oil or releases of other hazardous substances from industrial, municipal, and nonpoint sources. To support this assessment, information was compiled on the chemical composition of sediment and pore water; on the toxicity of whole sediments, pore water, and elutriates; and on the status of benthic invertebrate communities. The data on each of these indicators were compared to regionally relevant benchmarks to assess the presence and extent of injury to surface water resources ( i.e., sediments) or biological resources ( i.e., sediment-dwelling organisms). The results of this assessment indicate that sediment injury has occurred throughout the assessment area, with up to four distinct lines of evidence demonstrating injury within the various reaches. The primary contaminants of concern ( i.e., those substances that are present at concentrations that are sufficient to cause or substantially contribute to sediment injury) include metals, polycyclic aromatic hydrocarbons, and total polychlorinated biphenyls.

Development of an index of biotic integrity for the Little Arkansas River Basin, Kansas

An index of biotic integrity (IBI) was developed for the Little Arkansas River Basin (LARB) in south-central Kansas by establishing a reference condition for the watershed. Twelve metrics, in six categories, were chosen for use in the IBI. Fish assemblages from 30 sites were selected to represent the highest quality sites (reference sites) remaining in the LARB. In addition, 20 historical sites were used to show changes in the watershed over the last century. The modified IBI was then tested at 10 sites within the basin to assess the affects of urban and agricultural disturbances on fish community structure in the Wichita area. IBI scores were statistically lower for the urban versus the agricultural sites. Overall, IBI scores rated from poor to fair, supporting the contention that the fish communities within the LARB are impaired.

Acute hepatic failure precipitated in a patient with subclinical liver disease by vibrionic and clostridial septicemia

A case of fatal septicemia caused by Vibrio vulnificus and Clostridium bifermentans in a patient with subclinical liver disease is described. The patient appeared to recover from the infection initially after antibiotic therapy but finally succumbed to rapidly developing hepatic failure. Postmortem examination revealed hemochromatosis. The pathogenesis of the polymicrobial septicemia and hepatic failure is discussed in the light of the published literature.