Clinical aspects of ballistic peripheral nerve injury: shrapnel versus gunshot

Objectives

Ballistic injuries to peripheral nerves pose special challenges in terms of indications, timing and type of surgical intervention. The aim of the present work was to analyze our experience in the surgical treatment of peripheral nerve ballistic injuries with respect to the mechanism of injury (gunshot versus shrapnel), and identify common and dissimilar prognostic factors in both types of injury.

Methods

This study was conducted on 42 patients totaling 58 nerves. Twenty-two patients (32 nerves) were injured by gunshot and 20 patients (26 nerves) by shrapnel. Median postoperative follow-up was 33 months (range 12 months to 14 years).

Results

Overall postoperative outcome appears to be more favorable for gunshot-wound (GSW) patients than shrapnel-injured patients, especially in terms of neuropathic pain relief (75 % vs. 58 % respectively, p < 0.05). Presence of foreign particles in shrapnel injured patients has a negative impact on the surgical outcome in terms of rate of pain improvement (28 % compared to 67 % in patients with and without foreign particles, respectively). Nerve graft reconstruction, rather than neurolysis, seems to be the more beneficial treatment for shrapnel-induced neuropathic pain (100 % vs. 47 % in improvement rate, respectively). Early surgical intervention (median 2 months after injury) significantly relieved neuropathic pain in 83 % of shrapnel-injured patients compared to 58 % in patients operated later.

Conclusions

This study suggests that shrapnel injury is more destructive for nerve tissue than gunshot injury. Our impression is that early surgical intervention in shrapnel injuries and split nerve grafting (especially when small fragments are recognized in the nerve) significantly improve the patient’s functional activity and quality of life.     

The role of statins in the prevention of contrast induced nephropathy: a meta-analysis of 8 randomized trials

Contrast induced nephropathy (CIN) is a common complication of coronary angiography/angioplasty. Prevention is the key to reduce the incidence of CIN and it begins with appropriate pre-procedural management. Statins have been shown to possess pleiotropic effects (anti-oxidant, anti-inflammatory and anti-thrombotic properties) and their effects on CIN were assessed in several studies with conflicting results. Aim of this meta-analysis is to evaluate the efficacy of short-term statins for the prevention of CIN in patients undergoing coronary angiography/percutaneous interventions. We performed formal searches of PubMed, EMBASE, Cochrane central register of controlled trials and major international scientific session abstracts from January 1990 to January 2014 of trials which compares short-term statins versus Placebo for the prevention of CIN in patients undergoing coronary angiography/angioplasty. Data regarding study design, statin dose, inclusion/exclusion criteria, number of patients, and clinical outcome was extracted by 2 investigators. Eight trials were included, with a total of 4734 patients. CIN occurred in 79/2,358 patients (3.3 %) treated with statins versus 153/2,376 patients (6.4 %) of the placebo group [OR 95 % CI 0.50 (0.38–0.66), p < 0.00001; p _het = 0.39]. Benefits were both observed with high-dose short-term statins [OR 95 % CI 0.44 (0.30–0.65), p < 0.0001; p _het = 0.16] and low-dose statins, [OR 95 % CI 0.58 (0.39–0.88), p = 0.010; p _het = 0.90]. By meta-regression analysis, no significant relationship was observed between benefits from statin therapy and patient’s risk profile (p = 0.26), LDL cholesterol (p = 0.4), contrast volume (p = 0.94) or diabetes rate (p = 0.38). This meta-analysis showed that among patients undergoing coronary angiography/percutaneous intervention the use of short-term statins reduces the incidence of CIN, and therefore is highly recommended even in patients with low LDL-cholesterol levels.     

Switching from high-dose clopidogrel to prasugrel in ACS patients undergoing PCI: a single-center experience

Prasugrel has been shown to be superior to clopidogrel in the setting of ACS patients undergoing coronary angioplasty. However, few data have been reported so far on those patients who switch from clopidogrel to prasugrel after coronary angioplasty. Aim of the current study was to evaluate the safety of prasugrel loading dose administration in ACS patients undergoing PCI and preatreated with high-dose clopidogrel. From May 2010 to December 2011 150 ACS patients undergoing coronary angioplasty and pretreated with high-dose clopidogrel, were switched to prasugrel loading dose soon after the procedure. They were matched (ratio 1:2) according to sex and age with a group of 300 ACS patients undergoing angioplasty and treated with high-dose clopidogrel only from May 2010 to December 2011. All demographic clinical and angiographic were collected. Primary endpoint was the rate of major bleeding complications (according to ACUITY trial definition) at 30-day follow-up. Secondary endpoints were: TIMI major and minor bleeding, definite stent thrombosis, major adverse cardiac events (MACE) and Net adverse cardiac events (NACE) at 30-day follow-up. The two groups of patients showed similar baseline demographic, and clinical characteristics. Most of the patients had unstable angina or non-ST segment elevation myocardial infarction. Almost (about 95 %) all patients underwent radial approach. No difference was observed in major bleeding complications according to both ACUITY (2.0 vs 2.0 %) and TIMI Major (0.7 vs 1.3 %) definition. No difference between the two groups was observed in terms of in-stent thrombosis, MACE and NACE at 30-day follow-up. Our observational study showed that switching to prasugrel with loading dose soon after angioplasty among ACS patients who were pretreated with clopidogrel seems to be well tolerated without overt evidence of heightened major bleeding. Future large randomized trials are certainly needed to confirm these findings.     

Land,irrigation water,greenhouse gas,and reactive nitrogen burdens of meat,eggs, and dairy production in the United States

Livestock production impacts air and water quality, ocean health, and greenhouse gas (GHG) emissions on regional to global scales and it is the largest use of land globally. Quantifying the environmental impacts of the various livestock categories, mostly arising from feed production, is thus a grand challenge of sustainability science. Here, we quantify land, irrigation water, and reactive nitrogen (Nr) impacts due to feed production, and recast published full life cycle GHG emission estimates, for each of the major animal-based categories in the US diet. Our calculations reveal that the environmental costs per consumed calorie of dairy, poultry, pork, and eggs are mutually comparable (to within a factor of 2), but strikingly lower than the impacts of beef. Beef production requires 28, 11, 5, and 6 times more land, irrigation water, GHG, and Nr, respectively, than the average of the other livestock categories. Preliminary analysis of three staple plant foods shows two- to sixfold lower land, GHG, and Nr requirements than those of the nonbeef animal-derived calories, whereas irrigation requirements are comparable. Our analysis is based on the best data currently available, but follow-up studies are necessary to improve parameter estimates and fill remaining knowledge gaps. Data imperfections notwithstanding, the key conclusion—that beef production demands about 1 order of magnitude more resources than alternative livestock categories—is robust under existing uncertainties. The study thus elucidates the multiple environmental benefits of potential, easy-to-implement dietary changes, and highlights the uniquely high resource demands of beef.Appreciation of the environmental costs of food production has grown steadily in recent years (e.g., refs. 1–3), often emphasizing the disproportionate role of livestock (4–12). Although potentially societally important, to date the impacts of this research on environmental policies (7, 13, 14) and individual dietary choices have been modest. Although pioneering early environmental burden estimates have tended to address wide food classes (notably the animal-based portion of the diet; e.g., refs. 9 and 15), most policy objectives and individual dietary choices are item specific.For example, a person may consider beef and chicken mutually interchangeable on dietary or culinary grounds. However, even if an individual estimate of the environmental cost of one item exists, it is often not accompanied by a directly comparable study of the considered alternative. Even in the unlikely event that both estimates are available, they are unlikely to consider the costs in terms of more than one metric, and often rely on disparate methodologies. Therefore, environmentally motivated dietary choices and farm policies stand to benefit from more finely resolved environutritional information. Although early work yielded a short list of item-specific environmental cost estimates (16), those estimates were often based on meager data, and addressed a single environmental metric (typically energy), thus requiring expansion, updating, and further analysis to enhance statistical robustness (8).Current work in the rapidly burgeoning field of diet and agricultural sustainability falls mostly into two complementary approaches. The first is bottom–up, applying rigorous life cycle assessment (LCA) methods to food production chains (17–22). Whereas early LCAs focused primarily on greenhouse gas (GHG) emissions (23–26), or in some cases GHGs and energy use (5, 27), more recent LCAs often simultaneously address several additional key metrics (17, 19–21, 28, 29), notably land, water, and reactive nitrogen (Nr, nitrogen fertilizer) use. Some studies also include emissions of such undesirable gases (in addition to GHGs) as smog precursors or malodors (30, 31), or adverse contributions to stream turbidity or erosional topsoil loss (e.g., refs. 32–34). This bottom–up approach is extremely important, and is poised to eventually merge with the top–down national efforts described in the next paragraph. This merger is not imminent, however, because the bottom–up approach considers one or at most a handful of farms at a time. Because of wide differences due to geography (35), year-to-year fluctuations (36), and agrotechnological practice (17, 37), numerous LCAs are required before robust national statistics emerge. Eventually, when a large and diverse LCA sample is at hand, the picture at the national level will emerge. Currently, however, the results from an LCA conducted in Iowa, for example, are unlikely to represent Vermont or Colorado. Given the current volume and scope of LCA research, and the complexity and variability of the problem, LCAs are still too few and too local to adequately sample the multifaceted, diverse US food system, and thus to collectively become nationally scalable.The second agricultural sustainability research thrust, into which this study broadly falls, is a top–down analysis of national (10, 16, 38) or global (8, 39–41) production statistics. The top–down approach we follow here is conceptually straightforward, as described schematically in Fig. 1. The environmental needs (land, irrigation water, etc.) of feed production are collected and distributed among the feed-consuming animal categories. This is termed the partitioning step, and is based on information about the number of animals raised or slaughtered mass in each category, as well as the characteristic feed ration in each category. The burdens attributed to each category are divided by the caloric or protein mass output of that animal category, yielding the final result, the environmental burden per consumed unit (e.g., agricultural land needed per ingested kilocalorie of poultry). This method is mainly appealing because it (i) circumvents the variability issues raised above by using national or global aggregations; and (ii) it is based on relatively solid data. For the United States in particular, US Department of Agriculture (USDA) data tend to be temporally consistent, nearly all-inclusive (e.g., records of the main crops are based on close to 100% of the production), and are reported after some (albeit modest) quality control. The key challenge with this approach is obtaining defensible numerical values and uncertainty ranges for the tens if not hundreds of parameters needed in the calculations, many of which are poorly constrained by available data. Such parameters include, for example, the average feed required per animal per day or per kilogram of weight gain, or the relative fraction of pasture in beef and dairy diets. The values vary as a function of, at least, season, geographical location, and agrotechnology used. One research effort, focused on a single location, is unlikely to yield definitive results. Significant progress in both approaches is primarily realized through the tenacious and painstaking amassing of many independent analyses over time; analyses from which robust, meaningful statistics can be derived. Because of the challenges associated with each of the research thrusts discussed above, quantitatively robust, multimetric estimates that are comparable across different categories and represent the average national environmental burdens have yet to be devised. Although estimates of total national energy use and GHG emissions by agriculture do exist (e.g., refs. 4, 5, 42, and 43), they require further statistical evaluation. The costs in terms of land, irrigation water, and Nr are even less certain.Open in a separate windowFig. 1.A simplified schematic representation of the information flow in calculating environmental burdens per consumed calorie or gram of protein. Feed supply and requirements (blue boxes at top) previously yielded (38) the fraction of each feed class consumed by each animal category; e.g., pork requires 23 ± 9% of concentrated feed. Combined with the environmental burdens (green boxes at left; land, irrigation water, and nitrogen fertilizer for each of the three feed classes), these fractions yield the burdens attributed to each animal category. Finally, dividing those overall environmental burdens attributed to each of the five livestock categories by the number of calories (or grams of protein) nationally consumed by humans in the United States, we reach the final result of this paper (yellow box at bottom). Most input data (left and top boxes) is known with relative accuracy based on USDA data, whereas environmental burdens of pasture and average feed requirements are less certain.Applying a top–down, uniform methodology throughout, here we present estimates of land, irrigation water, GHG, and Nr requirements of each of the five main animal-based categories in the US diet—dairy, beef, poultry, pork, and eggs—jointly providing 96% of the US animal-based calories. We do not analyze fish for two reasons. First, during the period 2000–2013, fish contributed ≈14 kcal per person per day, ≈0.5% of the total and 2% of the animal-based energy (750 kcal per person per day) in the mean American diet (44). In addition, data addressing feed use by fisheries and aquaculture are very limited and incomplete (relative to the five categories considered). We do not claim to cover all important environmental impacts of livestock production. Rather, we focus on key metrics that can be reliably defined and quantified at the national level with currently available data.     

Detection of Cerebral Hyperperfusion Syndrome after Carotid Endarterectomy with CT Perfusion

We present the case of a 60‐year‐old female patient, who developed symptomatic internal carotid artery stenosis and subsequently underwent carotid endarterectomy. Four days after an uneventful surgery the patient developed confusion, seizures, and was admitted to the ICU. CT perfusion revealed reduced ispilateral time‐to‐peak and mean‐transient‐time and increased cerebral blood volume and cerebral blood flow, confirming the diagnosis of cerebral hyperperfusion syndrome. We thus propose CT perfusion as a diagnostic means for cerebral hyperperfusion syndrome, a syndrome that remains underdiagnosed.     

Monitoring stroke progression: in vivo imaging of cortical perfusion,blood–brain barrier permeability and cellular damage in the rat photothrombosis model

Focal cerebral ischemia is among the main causes of death and disability worldwide. The ischemic core often progresses, invading the peri-ischemic brain; however, assessing the propensity of the peri-ischemic brain to undergo secondary damage, understanding the underlying mechanisms, and adjusting treatment accordingly remain clinically unmet challenges. A significant hallmark of the peri-ischemic brain is dysfunction of the blood–brain barrier (BBB), yet the role of disturbed vascular permeability in stroke progression is unclear. Here we describe a longitudinal in vivo fluorescence imaging approach for the evaluation of cortical perfusion, BBB dysfunction, free radical formation and cellular injury using the photothrombosis vascular occlusion model in male Sprague Dawley rats. Blood–brain barrier dysfunction propagated within the peri-ischemic brain in the first hours after photothrombosis and was associated with free radical formation and cellular injury. Inhibiting free radical signaling significantly reduced progressive cellular damage after photothrombosis, with no significant effect on blood flow and BBB permeability. Our approach allows a dynamic follow-up of cellular events and their response to therapeutics in the acutely injured cerebral cortex.     

Victims of war—Psychoendocrine evidence for the impact of traumatic stress on psychological well-being of adolescents growing up during the Israeli–Palestinian conflict

Violent conflicts are severe traumatic stressors with detrimental effects on physical and mental health, with children and adolescents being particularly at risk. For the hypothalamic–pituitary–adrenal (HPA) axis, characteristic patterns of dysregulation in trauma-exposed individuals have been shown. This study set out to investigate self-reported mental well-being in Palestinian adolescents growing up during the Israeli–Palestinian conflict. Hair cortisol concentrations (HCC) as a psychoendocrine marker for long-term HPA axis aberrations along with the potential protective factor sense of coherence (SoC; i.e., the global mindset to interpret the world and emerging stressors as comprehensible, manageable, and meaningful) were examined. Between 2014 and 2016, posttraumatic stress disorder (PTSD), depression, anxiety, HCC, and SoC were examined in 233 adolescents aged 11 to 16 from the West Bank. More than half of the participants reported trauma exposure, with 40% fulfilling the criteria of a preliminary PTSD diagnosis and a high prevalence of anxiety and depression. HCC was significantly elevated in the PTSD subgroup compared to the subgroup not exposed to any traumatic events (p = 0.046), with trauma-exposed individuals in between. HCC was further associated with typical sequelae of traumatic stress. Notably, SoC was inversely related to self-reported psychopathology, as well as to HCC in the trauma group. The results illustrate the situation of adolescents exposed to chronic traumatic stress and extend the literature on aberrant HPA axis functioning under such conditions. They also point out a central role of SoC, which may imply new strategies to aid individuals exposed to ongoing conflicts.