RESUMO
BACKGROUND: Non-technical skills (NTS) failures have been implicated in a large proportion of surgical errors. The objective of this meta-analysis was to investigate whether NTS training of theatre staff improves patient outcomes. METHODS: In a systematic literature search all interventional studies evaluating the effects of NTS training of theatre staff were identified. Primary outcomes included mortality, morbidity, readmission rate and length of hospital stay. Secondary outcomes included staff NTS, checklist use and technical surgical performance. Pooled odds ratios (OR) were determined for event rates and weighted mean differences (WMD) for continuous data. An inverse variance method in a random effects model was used for meta-analysis. RESULTS: A total of 1381 records were identified and nine studies were included. Meta-analysis of mortality was not carried out because only two controlled studies with different study designs were identified. No statistically significant differences were seen in complication rate (5 studies, OR 0.91 [0.73, 1.14]; p = 0.43), readmission rate (3 studies, OR 0.90 [0.63, 1.28], p = 0.56) and length of hospital stay (3 studies, WMD -0.88 days [-2.06, 0.31], p = 0.31) after NTS training. Of the secondary outcomes, an improvement of whole team NOTECHS II scores was observed in the intervention group (3 studies, WMD 6.97 [3.88, 10.06], p < 0.0001). Technical performance and checklist use were unchanged. CONCLUSIONS: This meta-analysis failed to find a statistically significant improvement of patient outcomes. These conclusions are based on a small number of heterogeneous studies. Further appropriately powered studies are likely to improve our understanding of the effects of NTS training.
Assuntos
Anestesiologia/educação , Competência Clínica , Cirurgia Geral/educação , Erros Médicos/prevenção & controle , Salas Cirúrgicas , Humanos , Tempo de Internação/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Melhoria de QualidadeRESUMO
Defective cardiac function during sepsis has been referred to as "cardiomyopathy of sepsis." It is known that sepsis leads to intensive activation of the complement system. In the current study, cardiac function and cardiomyocyte contractility have been evaluated in rats after cecal ligation and puncture (CLP). Significant reductions in left ventricular pressures occurred in vivo and in cardiomyocyte contractility in vitro. These defects were prevented in CLP rats given blocking antibody to C5a. Both mRNA and protein for the C5a receptor (C5aR) were constitutively expressed on cardiomyocytes; both increased as a function of time after CLP. In vitro addition of recombinant rat C5a induced dramatic contractile dysfunction in both sham and CLP cardiomyocytes, but to a consistently greater degree in cells from CLP animals. These data suggest that CLP induces C5aR on cardiomyocytes and that in vivo generation of C5a causes C5a-C5aR interaction, causing dysfunction of cardiomyocytes, resulting in compromise of cardiac performance.
Assuntos
Cardiomiopatias/etiologia , Complemento C5a/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Sepse/complicações , Animais , Anticorpos/farmacologia , Cardiomiopatias/metabolismo , Cardiomiopatias/fisiopatologia , Células Cultivadas , Modelos Animais de Doenças , Expressão Gênica , Técnicas In Vitro , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , RNA Mensageiro/metabolismo , Ratos , Receptor da Anafilatoxina C5a/genética , Sarcômeros/fisiologia , Sepse/metabolismo , Sepse/fisiopatologia , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
BACKGROUND: Burn injury is frequently complicated by bacterial infection. Following burn injury, exposure to endotoxin produces a measurable decrease in cardiomyocyte sarcomere contractile function. Lipopolysaccharide-binding protein (LBP) is an acute phase protein that potentiates the recognition of lipopolysaccharide (LPS) by binding to the lipid A moiety of LPS. In this study, we sought to determine the effect of recombinant rat LBP (rLBP) on cardiomyocyte sarcomere function after burn or sham injury in the presence or absence of bacterial endotoxin. METHODS: Rats underwent a full-thickness 30% total body surface area scald or sham burn. At 24 h post-injury, cardiomyocytes were isolated, plated at 50,000 cells/well, and incubated with 50 µg/mL LPS and rLBP or chloramphenicol acetyltransferase (BVCat, an irrelevant control protein produced using the same expression system as rLBP) at concentrations by volume of 1%, 5%, 10%, and 30%. Subsets of cardiomyocytes were incubated with 5% rat serum or 30% rLBP and blocking experiments were conducted using an LBP-like synthetic peptide (LBPK95A). In vitro sarcomere function was measured using a variable rate video camera system with length detection software. RESULTS: Co-culture of burn and sham injury derived cardiomyocytes with high-dose rLBP in the presence of LPS resulted in a significant reduction to the functional impairment observed in peak sarcomere shortening following exposure to LPS alone. LBP-like peptide LBPK95A at a concentration of 20 µg/mL, in the presence of LPS, abolished the ability of 30% rLBP and 5% rat serum to restore peak sarcomere shortening of cardiomyocytes isolated following burn injury to levels of function exhibited in the absence of endotoxin exposure. CONCLUSIONS: In the setting of LPS challenge following burn injury, rLBP at high concentrations restores cardiomyocyte sarcomere contractile function in vitro. Rather than potentiating the recognition of LPS by the cellular LPS receptor complex, rLBP at high concentrations likely results in an inhibitory binding effect that minimizes the impact of endotoxin exposure on cardiomyocyte function following thermal injury.
Assuntos
Proteínas de Fase Aguda/farmacologia , Queimaduras/complicações , Proteínas de Transporte/farmacologia , Insuficiência Cardíaca/etiologia , Glicoproteínas de Membrana/farmacologia , Contração Miocárdica/efeitos dos fármacos , Animais , Apoptose , Sequência de Bases , Queimaduras/fisiopatologia , Relação Dose-Resposta a Droga , Marcação In Situ das Extremidades Cortadas , Lipopolissacarídeos/farmacologia , Masculino , Dados de Sequência Molecular , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Sarcômeros/efeitos dos fármacos , Sarcômeros/fisiologiaRESUMO
INTRODUCTION: Septic encephalopathy secondary to a breakdown of the blood-brain barrier (BBB) is a known complication of sepsis. However, its pathophysiology remains unclear. The present study investigated the effect of complement C5a blockade in preventing BBB damage and pituitary dysfunction during experimental sepsis. METHODS: Using the standardised caecal ligation and puncture (CLP) model, Sprague-Dawley rats were treated with either neutralising anti-C5a antibody or pre-immune immunoglobulin (Ig) G as a placebo. Sham-operated animals served as internal controls. RESULTS: Placebo-treated septic rats showed severe BBB dysfunction within 24 hours, accompanied by a significant upregulation of pituitary C5a receptor and pro-inflammatory cytokine expression, although gene levels of growth hormone were significantly attenuated. The pathophysiological changes in placebo-treated septic rats were restored by administration of neutralising anti-C5a antibody to the normal levels of BBB and pituitary function seen in the sham-operated group. CONCLUSIONS: Collectively, the neutralisation of C5a greatly ameliorated pathophysiological changes associated with septic encephalopathy, implying a further rationale for the concept of pharmacological C5a inhibition in sepsis.
Assuntos
Barreira Hematoencefálica/metabolismo , Complemento C5a/antagonistas & inibidores , Complemento C5a/imunologia , Doenças da Hipófise/metabolismo , Doenças da Hipófise/prevenção & controle , Sepse/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Imunoglobulina G/farmacologia , Imunoglobulina G/uso terapêutico , Masculino , Doenças da Hipófise/fisiopatologia , Ratos , Ratos Sprague-Dawley , Receptor da Anafilatoxina C5a/antagonistas & inibidores , Receptor da Anafilatoxina C5a/biossíntese , Sepse/complicações , Sepse/tratamento farmacológicoRESUMO
We recently showed that acute oxidant-related lung injury (ALI) in rats after application of 2-chloroethyl ethyl sulfide (CEES) is attenuated by the airway instillation of antioxidants. We investigated whether intratracheal administration of antioxidant-containing liposomes immediately after instillation of CEES would attenuate short-term as well as long-term (fibrotic) effects of CEES-induced lung injury. In the acute injury model (4 h after injury), N-acetylcysteine (NAC)-containing liposomes were protective and reduced to baseline levels both the lung permeability index and the appearance of proinflammatory mediators in bronchoalveolar lavage fluids from CEES-exposed lungs. Similar results were obtained when rat alveolar macrophages were incubated in vitro with either CEES or lipopolysaccharide in the presence of NAC-liposomes. When lung fibrosis 3 weeks after CEES was quantitated by using hydroxyproline content, liposomes containing NAC or NAC + glutathione had no effects, but liposomes containing alpha/gamma-tocopherol alone or with NAC significantly suppressed the increase in lung hydroxyproline. The data demonstrate that delivery of antioxidants via liposomes to CEES-injured lungs is, depending on liposomal content, protective against ALI, prevents the appearance of proinflammatory mediators in bronchoalveolar fluids, and suppresses progressive fibrosis. Accordingly, the liposomal strategy may be therapeutically useful in CEES-induced lung injury in humans.
Assuntos
Antioxidantes , Lipossomos , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/prevenção & controle , Acetilcisteína/administração & dosagem , Acetilcisteína/metabolismo , Acetilcisteína/uso terapêutico , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Líquido da Lavagem Broncoalveolar/química , Quimiocinas/metabolismo , Citocinas/metabolismo , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/uso terapêutico , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Lipossomos/metabolismo , Lipossomos/uso terapêutico , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/metabolismo , Masculino , Gás de Mostarda/análogos & derivados , Gás de Mostarda/farmacologia , Ratos , Ratos Long-Evans , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/patologia , Tocoferóis/administração & dosagem , Tocoferóis/metabolismo , Tocoferóis/uso terapêuticoRESUMO
Despite intensive ongoing research efforts, the mortality of patients with sepsis remains unacceptably high. A significant number of clinical trials have failed to produce sufficient therapeutic strategies despite showing promising results in animal models. So far, many studies have focused on deterioration of the humoral and cellular components of the immune system, the main cause of death in septic patients being multi-organ failure. However, not much is known about the effects of the complement system on parenchymal cells of organs such as the heart. Recently, septic cardiomyopathy has been recognized as one of the major complications during sepsis, often determining the clinical outcome. In this review, we describe molecular events which are thought to be related to cardiac dysfunction during sepsis. A special emphasis will be placed on the complement system, which generates powerful anaphylatoxins (such as C5a) and which has recently been associated with septic cardiomyopathy. Together with the impact on cardiac function of various cytokines we will provide a synopsis of the current knowledge regarding the pathophysiology underlying cardiac failure during sepsis with a special emphasis on C5a and C5aR.
Assuntos
Proteínas do Sistema Complemento/fisiologia , Insuficiência Cardíaca/etiologia , Sepse/complicações , Animais , Citocinas/fisiologia , Proteína HMGB1/fisiologia , Coração/fisiopatologia , Humanos , Inflamação/fisiopatologia , Fatores Inibidores da Migração de Macrófagos/fisiologia , Proteínas de Membrana/fisiologia , Óxido Nítrico/fisiologia , Receptor da Anafilatoxina C5a , Receptores de Complemento/fisiologiaRESUMO
BACKGROUND: Although the inflammatory response is a prerequisite for wound healing, excessive activation of the innate immune system can induce epithelial cell damage and apoptosis, which may further compromise dermal integrity. In a noninfectious burn wound model, we previously demonstrated that topical inhibition of p38 MAPK, an important inflammatory signaling pathway, attenuated epithelial cell damage and apoptosis. We now question whether attenuating local inflammation would weaken bacterial wound resistance and compromise host defense. METHODS: Rats received 30% total body surface area burn, and the wound was treated with topical application of a p38 MAPK inhibitor or vehicle. At 24 hours after injury, burn wounds were inoculated with Pseudomonas aeruginosa. At 48 hours postinjury, animals were sacrificed, and the burn wound was analyzed. RESULTS: Inoculating burn wounds induced significant bacterial growth. Dermal inflammatory changes were markedly accentuated in the inoculated animals. Topical p38 MAPK inhibition reduced the proinflammatory cytokine expression in the burn wounds and neutrophil sequestration with or without bacterial inoculation. Interestingly, the bacterial wound growth was significantly attenuated in animals treated with topical p38 MAPK inhibitor. CONCLUSIONS: Topical p38 MAPK inhibition attenuated wound inflammation without interfering with bacterial host defense. Attenuation of excessive burn wound inflammatory signaling may prevent secondary damage of the dermal barrier and reduce the growth of opportunistic pathogens.
Assuntos
Queimaduras/microbiologia , Inibidores Enzimáticos/administração & dosagem , Imidazóis/administração & dosagem , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Piridinas/administração & dosagem , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Administração Tópica , Animais , Queimaduras/complicações , Queimaduras/metabolismo , Queimaduras/patologia , Quimiocina CXCL2 , Quimiocinas CXC/antagonistas & inibidores , Quimiocinas CXC/metabolismo , Ensaio de Unidades Formadoras de Colônias , Citocinas/antagonistas & inibidores , Dermatite/etiologia , Dermatite/microbiologia , Dermatite/patologia , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Mediadores da Inflamação/antagonistas & inibidores , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Óxido Nítrico/antagonistas & inibidores , Infecções por Pseudomonas , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Pele/metabolismoRESUMO
Thermal injury induces dermal inflammatory and proapoptotic signaling. These phenomena extend burn wound size and trigger a systemic inflammatory response, factors known to adversely affect outcomes. p38MAPK is known to trigger inflammatory responses and induce epithelial proapoptotic genes. We hypothesize that topical p38MAPK inhibition will attenuate excessive inflammatory and apoptotic signaling and reduce dermal tissue loss. Rats were given a 30% total body surface area partial thickness burn or sham injury. Some of the animals were treated with a p38MAPK inhibitor or vehicle, which was applied directly to the wound. Dermal inflammation was investigated with enzyme-linked immunosorbent assay, reverse transcriptase polymerase chain reaction, myeloperoxidase assay, and Evans blue extravasation. Apoptotic changes were detected using terminal deoxynucleotidyl transferase dUTP nick-end labeling assay and Caspase-3 in situ staining. Burn injury activated dermal p38MAPK and induced a significant rise in dermal IL-6, TNF-alpha, and IL-1beta expression. Neutrophil sequestration, microvascular damage, and hair follicle apoptosis were significantly elevated after injury. Topical p38MAPK inhibition significantly attenuated downstream dermal p38MAPK targets, proinflammatory cytokine expression, neutrophil sequestration, and microvascular injury. A significant reduction in hair follicle apoptosis was seen. This study demonstrates the attenuation of burn-induced cellular stress by topical application of p38MAPK inhibitors. Blunting early excessive inflammatory signaling may be an efficient strategy to improve patient outcomes after burn injury.
Assuntos
Apoptose/efeitos dos fármacos , Queimaduras/tratamento farmacológico , Dermatite/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Imidazóis/farmacologia , Piridinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Administração Tópica , Animais , Queimaduras/complicações , Queimaduras/patologia , Quimiocinas CXC/metabolismo , Citocinas/efeitos dos fármacos , Citocinas/genética , Citocinas/metabolismo , Dermatite/patologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Imidazóis/administração & dosagem , Interleucina-6/genética , Masculino , Neutrófilos/efeitos dos fármacos , Piridinas/administração & dosagem , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
A component of multiorgan dysfunction in burned patients is heart failure. Burn trauma induces cytokine synthesis of interleukin (IL) 1beta, IL-6, and tumor necrosis factor alpha (TNF-alpha) which can negatively impact cardiac function. Infectious complications are common following severe burn injury. We hypothesized that burn injury and lipopolysaccharide (LPS) exposure independently influence peak cardiomyocyte contraction and cytokine secretion. Rats underwent a full-thickness 30% total body surface area scald or sham burn. At 1, 6, 12, and 24 h after burn, cardiomyocytes were isolated and incubated with increasing LPS doses. Peak sarcomere shortening and contractile velocity parameters were recorded using a variable-rate video camera with sarcomere length detection software. Supernatants were assayed for IL-1beta, IL-6, and TNF-alpha by ELISA. Peak sarcomere shortening was decreased in the burn group at 1, 6, 12, and 24 h after burn. IL-1beta, IL-6, and TNF-alpha levels were increased in cardiomyocytes isolated 1 h after burn compared with sham controls, but returned to sham levels at 6, 12, and 24 h after burn. LPS exposure caused dose-dependent decreases in sarcomere shortening in sham and burn animals. LPS exposure did not produce increased cardiomyocyte cytokine expression. Burn injury diminished peak sarcomere shortening. Whereas exposure to LPS did not have an effect on cardiomyocyte cytokine expression, LPS significantly inhibited sarcomere shortening in a dose-dependent fashion. Combined burn and LPS exposure inhibited sarcomere shortening more than each alone. These results demonstrate that LPS exposure and burn injury independently decrease peak cardiac shortening. These decreases did not directly correlate with the levels of cytokines released in response to each stressor.
Assuntos
Queimaduras/metabolismo , Citocinas/biossíntese , Insuficiência Cardíaca/metabolismo , Contração Miocárdica , Miócitos Cardíacos/metabolismo , Sarcômeros/metabolismo , Animais , Queimaduras/complicações , Queimaduras/patologia , Células Cultivadas , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Lipopolissacarídeos/farmacologia , Masculino , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley , Sarcômeros/patologia , Fatores de TempoRESUMO
BACKGROUND: Severe burn trauma leads to an immediate and strong inflammatory response inciting cardiac dysfunction that is associated with high morbidity and mortality. The aim of this study was to determine whether transdermal application of nicotine could influence the burn-induced cardiac dysfunction via its known immunomodulatory effects. MATERIAL AND METHODS: A standardized rat burn model was used in 35 male Sprague Dawley rats. The experimental animals were divided into a control group, a burn trauma group, a burn trauma group with additional nicotine treatment, and a sham group with five experimental animals per group. The latter two groups received nicotine administration. Using microtip catheterization, functional parameters of the heart were assessed 12 or 24 hours after infliction of burn trauma. RESULTS: Burn trauma led to significantly decreased blood pressure (BP) values whereas nicotine administration normalized BP. As expected, burn trauma also induced a significant deterioration of myocardial contractility and relaxation parameters. After application of nicotine these adverse effects were attenuated. CONCLUSION: The present study showed that transdermal nicotine administration has normalizing effects on burn-induced myocardial dysfunction parameters. Further research is warranted to gain insight in molecular mechanisms and pathways and to evaluate potential treatment options in humans.
Assuntos
Queimaduras/fisiopatologia , Coração/fisiopatologia , Contração Miocárdica/efeitos dos fármacos , Nicotina/farmacologia , Administração Cutânea , Animais , Queimaduras/tratamento farmacológico , Masculino , Ratos , Ratos Sprague-Dawley , Índices de Gravidade do TraumaRESUMO
Lipoteichoic acid (LTA) is the key pathogenic factor of gram-positive bacteria and contributes significantly to organ dysfunction in sepsis, a frequent complication in critical care patients. We hypothesized that LTA directly affects cardiomyocyte function, thus contributing to cardiac failure in sepsis. This study was designed to evaluate the effects of LTA on contractile properties and calcium-transients of isolated adult rat cardiomyocytes. When myocytes were exposed to LTA for 1h prior to analysis, the amplitudes of calcium-transients as well as sarcomere shortening increased to 130% and 142% at 1 Hz stimulation frequency. Relengthening of sarcomeres as well as decay of calcium-transients was accelerated after LTA incubation. Exposure to LTA for 24 h resulted in significant depression of calcium-transients as well as of sarcomere shortening compared to controls. One of the major findings of our experiments is that LTA most likely affects calcium-handling of the cardiomyocytes. The effect is exacerbated by reduced extracellular calcium, which resembles the clinical situation in septic patients. Functionally, an early stimulating effect of LTA with increased contractility of the cardiomyocytes may be an in vitro reflection of early hyperdynamic phases in clinical sepsis. Septic disorders have been shown to induce late hypodynamic states of the contractile myocardium, which is also supported at the single-cell level in vitro by results of our 24h-exposure to LTA.
Assuntos
Cálcio/metabolismo , Lipopolissacarídeos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Sarcômeros/efeitos dos fármacos , Ácidos Teicoicos/farmacologia , Animais , Cálcio/farmacologia , Células Cultivadas , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Lipopolissacarídeos/metabolismo , Masculino , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Ratos , Ratos Sprague-Dawley , Sarcômeros/fisiologia , Sepse/metabolismo , Sepse/fisiopatologia , Análise de Célula Única/métodos , Staphylococcus aureus/metabolismo , Ácidos Teicoicos/metabolismo , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Advanced strategies in reconstructive microsurgery and especially free tissue transfer with advanced microvascular techniques have been routinely applied and continuously refined for more than three decades in day-to-day clinical work. Bearing in mind the success rates of more than 95%, the value of these techniques in patient care and comfort (one-step reconstruction of even the most complex tissue defects) cannot be underestimated. However, anticoagulative protocols and practices are far from general acceptance and - most importantly - lack the benchmark of evidence basis while the reconstructive and microsurgical methods are mostly standardized. Therefore, the aim of our work was to review the actual literature and synoptically lay out the mechanisms of action of the plethora of anticoagulative substances. The pharmacologic prevention and the surgical intervention of thrombembolic events represent an established and essential part of microsurgery. The high success rates of microvascular free tissue transfer as of today are due to treatment of patients in reconstructive centers where proper patient selection, excellent microsurgical technique, tissue transfer to adequate recipient vessels, and early anastomotic revision in case of thrombosis is provided. Whether the choice of antithrombotic agents is a factor of success remains still unclear. Undoubtedly however the lack of microsurgical experience and bad technique can never be compensated by any regimen of antithrombotic therapy. All the more, the development of consistent standards and algorithms in reconstructive microsurgery is absolutely essential to optimize clinical outcomes and increase multicentric and international comparability of postoperative results and complications.
Assuntos
Anticoagulantes/uso terapêutico , Procedimentos de Cirurgia Plástica/efeitos adversos , Pré-Medicação/métodos , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Humanos , Resultado do TratamentoRESUMO
INTRODUCTION: Many studies have demonstrated the existence of an anti-inflammatory, parasympathetic pathway, termed as the inflammatory reflex. Burn-induced heart failure has been investigated in many previous studies. Proinflammatory cytokines, such as TNF-alpha, IL-1beta, and IL-6, have been shown to play a key pathogenetic role and vagus nerve stimulation attenuates proinflammatory cytokine production. This study was designed to evaluate postburn alterations of cardiac functional parameters after vagal electrostimulation. MATERIAL AND METHODS: A 30% total body surface area standardized, full-thickness rat burn model was used. Electric stimulation of the vagus nerve was performed. The following functional cardiac parameters were measured by ventricular microcatheterization: Maximal and minimal left ventricular pressure, mean left ventricular pressure, end-diastolic pressure (EDP), positive and negative pressure rise and fall (+/-dP/dt), cardiac contractility index, and assessment of the heart rate. RESULTS: Vagus nerve stimulation improved maximal and minimal left ventricular pressure values compared with burn-only animals. End-diastolic pressure was elevated significantly in stimulated animals; however, EDP values were comparable with those in sham-injured animals. Analyzing positive and negative pressure development, +/-dP/dt was restored to levels measured in sham-injured animals but not to control animal levels. No variations in heart rate were found. CONCLUSION: We as well as others have shown that inflammation after burn injury is a key pathogenetic element, and this study provides new evidence that cardiac function is also improved by vagus nerve stimulation. These results lead us to consider novel therapeutic options for the treatment of postburn cardiac dysfunction.
RESUMO
BACKGROUND: Topical inhibition of activated p38 MAPK within burn wounds attenuates the local and systemic inflammatory response. In this study, we investigated the effects of local activated p38 MAPK inhibition on burn-induced cardiac dysfunction. METHODS: Using a standardized rat model of scald burn injury, rats were given a 30% total body surface area partial thickness burn or sham injury, and the wounds were treated with an activated p38 MAPK inhibitor (SB) or vehicle. Systemic blood pressure measurements were recorded in vivo followed by in vitro assessment of sarcomere contraction in single-cell suspensions of isolated cardiomyocytes. RESULTS: Systolic blood pressure or maximum left ventricular pressures in vivo and peak cardiomyocyte sarcomere contractility in vitro were significantly reduced after burn injury. These functional deficits were abolished 24 h after burn injury following local p38 MAPK inhibition. In vitro incubation of normal cardiomyocytes with homogenate from burned skin or burn serum resulted in a similar pattern of impaired cardiomyocyte contractility. These effects were reversed in normal cardiomyocytes exposed to burn skin homogenates treated topically with a p38 MAPK inhibitor. A Western blot analysis showed that cardiac p38 MAPK activation was not affected by dermal blockade of activated p38 MAPK, arguing against systemic absorption of the inhibitor and indicating the involvement of systemic cytokine signaling. CONCLUSION: Topical activated p38 MAPK inhibition within burned skin attenuates the release of proinflammatory mediators and prevents burn-induced cardiac dysfunction after thermal injury. These results support the inhibition of burn-wound inflammatory signaling as a new therapeutic approach to prevent potential postthermal injury multiorgan dysfunction syndrome.
Assuntos
Queimaduras/fisiopatologia , Imidazóis/farmacologia , Contração Miocárdica/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Sarcômeros/efeitos dos fármacosRESUMO
INTRODUCTION: The interaction of the CNS and the immune system is well known. A parasympathetic anti-inflammatory pathway has recently been described. Both electrical and pharmacological parasympathetic stimulation attenuate proinflammatory mediator generation. Burn induces abacterial cytokine generation and we sought to evaluate whether parasympathetic stimulation after experimental burn decreases cardiodepressive mediator generation. MATERIAL AND METHODS: A 30% TBSA full-thickness rat burn model was used. After microsurgical preparation of the cervical portion of the vagus nerve, we performed electric vagus nerve stimulation. Serum was harvested and organ samples of heart and liver were homogenized. Samples were subjected to sandwich-ELISA specific for TNF-alpha, IL-1beta and IL-6. Heart rate measurements were done using left ventricular microcatheterization. Statistical analysis was done using Student's t-tests and analysis of variance (ANOVA). RESULTS: Burn induced a significant rise of TNF-alpha, IL-1beta and IL-6 in organ homogenates and serum. After cervical vagal electrostimulation, serum and organ homogenate levels of proinflammatory cytokines were markedly reduced compared to burn controls. Left ventricular microcatheter assessment demonstrated no cardiodepressive effect of the vagal stimulation itself. CONCLUSION: Our results encourage further research regarding the neuroimmunologic background of burn, possibly leading to the development of a novel therapeutic approach to burn-induced organ dysfunction and immunodysregulation.
Assuntos
Queimaduras/imunologia , Citocinas/metabolismo , Estimulação do Nervo Vago/métodos , Animais , Queimaduras/fisiopatologia , Queimaduras/terapia , Citocinas/sangue , Frequência Cardíaca , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Interleucina-1beta/sangue , Interleucina-1beta/metabolismo , Interleucina-6/sangue , Interleucina-6/metabolismo , Fígado/imunologia , Masculino , Miocárdio/imunologia , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/metabolismoRESUMO
BACKGROUND: Complications arising from accidental intraarterial drug injections have been described in the past. However, given the multitude of injected substances and complex pathophysiology, guidelines regarding diagnosis and management of patients with intraarterial injections remain vague. As such it remains unclear, when to expect limb ischemia and whether and for how long to monitor patients after intraarterial injections. CASE REPORT: We present the case of a "near miss event" in an i.v. drug abuser presenting to the emergency department 3 hours after injection of water dissolved zolpidem (Ambientrade mark) tablets into the right ulnar artery. Chief complaint was forearm pain. Clinical examination at the time revealed no concern for limb ischemia and patient was discharged. The patient returned unplanned 18 hours after injection with an ischemic right hand. Angiography revealed no flow in the distal ulnar artery and minimal flow in the palmar arch. Emergent intraarterial thrombolysis with Urokinase was performed and restored hand perfusion. Clinical follow-up 3 months after injury showed full recovery with regular recapillarisation and normal Allen test. CONCLUSION: This case report highlights the need to rigorously monitor patients with suspected intraarterial injections for potential delayed onset of limb ischemia. This is to our knowledge the first described case report of a successful revascularization after prolonged ischemia with delayed onset after zolpidem injection. We recommend close monitoring of these patients for at least 24 hours in addition to starting prophylactic anticoagulation.
RESUMO
Erb's palsy is well known to physicians across medical specialties, and its clinical manifestations present a formidable challenge to reconstructive surgeons. Although the condition is well established, knowledge pertaining to its namesake, Wilhelm Heinrich Erb, is rather obscure in the existing scientific literature. Erb was influential not only through his description of classic brachial plexus palsy involving the superior (or upper) roots, but also by his indelible contributions to our understanding of peripheral nerve physiology, deep tendon reflexes, and the muscular dystrophies. Erb's contributions to medicine transcend specialty boundaries. In this article, the authors seek to convey his scientific achievements and the character of the man through translation of his German manuscripts. These texts, complemented by the existing English literature, provide a unique perspective on Wilhelm Heinrich Erb's contribution to medicine. The authors will also emphasize his role in describing and clarifying the nature of Erb's palsy.
Assuntos
Neuropatias do Plexo Braquial/história , Eletrodiagnóstico/história , Epônimos , Alemanha , História do Século XIX , História do Século XX , Humanos , Doenças do Sistema Nervoso/históriaRESUMO
BACKGROUND: Beta-adrenoreceptor blocker (beta-blocker) therapy may improve outcomes in surgical patients by decreasing cardiac oxygen consumption and hypermetabolism. Because beta-blockers can lower the systemic blood pressure and cerebral perfusion pressure, there is concern regarding their use in patients with head injury. However, beta-blockers may protect beta-receptor rich brain cells by attenuating cerebral oxygen consumption and metabolism. We hypothesized that beta-blockers are safe in trauma patients, even if they have suffered a significant head injury. METHODS: Using pharmacy and trauma registry data of a Level I trauma center, we identified a cohort of trauma patients who received beta-blockers during their hospital stay (beta-cohort). Trauma admissions who did not receive beta-blockers were in the control cohort. beta-blocker status, in combination with other variables associated with mortality, were placed in a stepwise multivariate logistic regression to identify independent predictors of fatal outcome. RESULTS: In all, 303 (7%) of 4,117 trauma patients received beta-blockers. In the beta-cohort, 45% of patients were on beta-blockers preinjury. The most common reason to initiate beta-blocker therapy was blood pressure (60%) and heart rate (20%) control. The overall mortality rate was 5.6% and head injury was considered to be the major cause of death. After adjusting for age, Injury Severity Scale score, blood pressure, Glasgow Coma Scale score, respiratory status, and mechanism of injury, the odds ratio for fatal outcome was 0.3 (p < 0.001) for beta-cohort as compared with control. Decreased risk of fatal outcome was more pronounced in patients with a significant head injury. CONCLUSIONS: beta-blocker therapy is safe and may be beneficial in selected trauma patients with or without head injury. Further studies looking at beta-blocker therapy in trauma patients and their effect on cerebral metabolism are warranted.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Ferimentos e Lesões/tratamento farmacológico , Antagonistas Adrenérgicos beta/efeitos adversos , Estudos de Casos e Controles , Traumatismos Craniocerebrais/tratamento farmacológico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
OBJECTIVE: We previously showed that topical inhibition of inflammatory signaling in burn wounds reduced systemic inflammatory response and burn-induced pulmonary inflammation. We hypothesized that this topical intervention would attenuate burn-induced lung injury, improve pulmonary function, protect lungs from bacterial invasion, and reduce mortality. DESIGN: Controlled, in vivo, laboratory study. SETTING: University laboratory. SUBJECTS: Female mice, 8-10 wks old. INTERVENTIONS: Animals received 30% total body surface area burn followed by topical application of a specific inhibitor of p38 mitogen-activated protein kinase, a key inflammatory signaling pathway, or vehicle to the wound. Twenty-four hours after injury, pulmonary collagen deposition and pulmonary function were assessed. One day postburn, some of the animals received intratracheal instillation of Klebsiella pneumoniae and were subsequently monitored for 7 days. MEASUREMENTS AND MAIN RESULTS: Topical inhibition of p38 mitogen-activated protein kinase significantly decreased pulmonary collagen deposition and prevented a decline in pulmonary function at 1 day after burn injury. Compared with sham controls, animals with burn injury had a significantly higher mortality in response to intratracheal bacterial challenge. Application of p38 mitogen-activated protein kinase inhibitor to the burn wound attenuated pulmonary neutrophil infiltration and reduced the mortality rate to a level experienced by sham controls. CONCLUSIONS: Inflammatory source control in burn wounds with topical p38 mitogen-activated protein kinase inhibition attenuates acute lung injury, avoids pulmonary dysfunction, protects lungs from bacterial challenge, and improves survival.