Assuntos
Acetaminofen/toxicidade , Acetilcisteína/administração & dosagem , Analgésicos não Narcóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/terapia , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/terapia , Troca Plasmática , Acetaminofen/administração & dosagem , Acetaminofen/farmacocinética , Amônia/sangue , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/farmacocinética , Doença Hepática Induzida por Substâncias e Drogas/sangue , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Humanos , Hipotermia Induzida , Lactente , Unidades de Terapia Intensiva Pediátrica , Falência Hepática Aguda/sangue , Testes de Função Hepática , Plasma , Infecções Respiratórias/tratamento farmacológicoRESUMO
BACKGROUND: In cyanotic congenital heart disease, oxygen delivery is impaired either by reduced pulmonary perfusion or by limited entry of oxygenated blood into the systemic circulation. Additional impairment of oxygen delivery (eg, in pulmonary hypertension) leads to hypoxic cerebral damage. Preoperative extracorporeal membrane oxygenation enables oxygenation in otherwise untreatable cases. METHODS: In 3 neonates suffering from cyanotic congenital heart disease (1 with tricuspid atresia and 2 with transposition of the great arteries) with arterial desaturation despite application of prostaglandins, balloon atrioseptostomy, and eventually inhaled nitric oxide during intermittent positive-pressure ventilation with an inspired oxygen fraction of 1, oxygenation could only be established by means of preoperative extracorporeal membrane oxygenation. We used a venovenous single-lumen cannula tidal-flow extracorporeal membrane oxygenation system described by Chevalier and associates that has previously been used for extracorporeal lung support. In this system, called AREC (assistence respiratoire extra-corporelle), alternating clamps and a nonocclusive roller pump were used. RESULTS: All 3 survived. CONCLUSIONS: We conclude that the AREC system enables sufficient preoperative oxygenation in patients with cyanotic congenital heart disease and hypoxia in spite of all conventional therapeutic means. This provides a stable preoperative condition for elective palliation or correction.
Assuntos
Oxigenação por Membrana Extracorpórea/instrumentação , Oxigenadores de Membrana , Transposição dos Grandes Vasos/cirurgia , Atresia Tricúspide/cirurgia , Cianose , Feminino , Humanos , Recém-Nascido , Masculino , Cuidados Pré-OperatóriosRESUMO
Although deficient DNA repair was proposed for neurodegenerative disorders including Down syndrome (DS), repair proteins for nucleotide excision repair have not been studied in brain yet. As one of the hypotheses for the pathogenesis of brain damage in DS and Alzheimer's disease (AD), is oxidative stress, and cells of patients with DS were shown to be more susceptible to ionizing irradiation. We decided to study expression of excision repair-cross-complementing (ERCC) gene products, proteins 80 and 89, representatives of repair genes known to be involved in the repair of different types of DNA damage. ERCC2-protein 80 kDa and ERCC3-protein p89 were determined in five individual brain regions of controls, aged DS and AD patients. Although different in the individual regions, DNA repair proteins were consistently higher in temporal and frontal lobes of patients with DS and higher in all brain regions of patients with AD. Our results are the first to describe DNA repair gene protein patterns in human brain regions providing the basis for further studies in this area. We showed that DNA repair genes ERCC2 and ERCC3 (excision-repair-cross-complementing) for nucleotide excision repair were increased at the protein level with the possible biological meaning that this increase may be compatible with and indicate ongoing (oxidative?) DNA damage.
Assuntos
Doença de Alzheimer/genética , Química Encefálica , DNA Helicases , Reparo do DNA , Proteínas de Ligação a DNA/genética , Síndrome de Down/genética , Proteínas de Drosophila , Proteínas/genética , Fatores de Transcrição , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Cerebelo/química , Colina O-Acetiltransferase/análise , Dano ao DNA , Proteínas de Ligação a DNA/análise , Síndrome de Down/metabolismo , Lobo Frontal/química , Humanos , Pessoa de Meia-Idade , Lobo Occipital/química , Especificidade de Órgãos , Lobo Parietal/química , Proteínas/análise , Valores de Referência , Lobo Temporal/química , Proteína Grupo D do Xeroderma PigmentosoRESUMO
Collagen type I is the major protein of bone matrix and significantly reduced in osteoporosis. We tested the effect of alpha - methyl - proline on collagen synthesis in the model of the ovariectomized rat. Collagen synthesis was studied at the transcriptional level using Northern and dot blotting and at the protein level using hydroxyproline determination and a specific dye binding collagen assay. Alpha - methyl- proline treatment significantly increased collagen synthesis as compared to untreated ovariectomized and estradiol treated ovariectomized rats and restored collagen synthesis to levels of sham operated rats. Proline analogues were described to stimulate procollagen synthesis at the transcriptional level, however, if incorporated, lead to negative collagen production due to rapid intracellular degradation of the deficient collagen. Our synthesized analogue is not being incorporated, thus not interfering with collagen conformation and can therefore induce collagen production.
Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Colágeno/biossíntese , Ovariectomia , Prolina/análogos & derivados , Animais , Northern Blotting , Peso Corporal , Colágeno/genética , Estradiol/farmacologia , Feminino , Hidroxiprolina/metabolismo , Prolina/farmacologia , Proteínas/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Sprague-DawleyRESUMO
Charcoal has been commonly used for enteral detoxication with few adverse effects. In toddlers charcoal can often be simply applied via a gastric tube. Regurgitation and aspiration is considered a rare event. We report the case of a 19-month-old boy who suffered endobronchial charcoal contamination followed by acute airway obstruction and severe respiratory failure despite a commonly used tube placement verification technique. Immediate intubation, tracheal suctioning, intravenous bronchodilators, and high frequency oscillatory ventilation (HFOV) were used to control hypercarbia and hypoxia. Eventually charcoal removal by bronchoscopy was successful. Chest X-ray investigation did not reflect the true amount of charcoal deposited endobronchially at any time. We conclude that gastric tube application of charcoal in children carries a risk of aspiration. This may lead to life-threatening respiratory failure with the need to provide artificial ventilation and bronchial lavage.
Assuntos
Carvão Vegetal/efeitos adversos , Insuficiência Respiratória/induzido quimicamente , Humanos , Lactente , Bem-Estar do Lactente , Masculino , Índice de Gravidade de DoençaRESUMO
Intraosseous (IO) puncture is considered for the administration of drugs and fluids when vascular access cannot be achieved rapidly. Adrenaline/epinephrine, adenosine, crystalloids, colloids and blood products can be applied and administered effectively using this route during resuscitation of children. This technique is relatively simple with complications of <1%. These may include tibial fracture, lower extremity compartment syndrome and osteomyelitis. A case is described in which a 3-month-old male infant presented for emergency resuscitation requiring IO infusion utilising both tibial bones. High doses of adrenaline (1:1000; 0.1 mg/kg) were administered in the right tibial epiphysis only after the standard initial concentration (1:10000; 0.01 mg/kg) had minimal effect. A local inflammatory reaction was noted 24 h later in the right tibial region, which developed into cutaneous necrosis, and was eventually resected. Radiologically, no osseous lesion could be demonstrated, however, a bone scintigram revealed osteomyelitis. Upon surgical revision, purulent destruction was evident requiring removal of the epiphysis and part of the metaphysis. Although osteomyelitis is a rare complication which may be caused by sepsis, or contamination during insertion, we speculate that adrenaline in high concentrations may promote the development of osteomyelitis and the drug should be applied cautiously in more diluted concentrations.
Assuntos
Infusões Intraósseas/efeitos adversos , Osteomielite/etiologia , Antibacterianos , Quimioterapia Combinada/uso terapêutico , Epinefrina/administração & dosagem , Evolução Fatal , Humanos , Lactente , Masculino , Agulhas , Osteomielite/tratamento farmacológico , Infecções Respiratórias/complicaçõesRESUMO
Adverse changes in cerebral hemodynamics during endotracheal suctioning have been reported in conventionally ventilated newborns, whereas observations on the effect of endotracheal suctioning during high-frequency ventilation have not been reported to date. The present study was designed to investigate the effect of endotracheal suctioning on cerebral hemodynamics in high-frequency and conventionally ventilated infants. Changes in cerebral concentration of oxygenated (cO(2)Hb) and deoxygenated hemoglobin (cHHb) and oxidized cytochrome aa3 (cCyt.aa3) were measured by noninvasive near-infrared spectroscopy. In an open prospective study, 26 suctioning periods in 9 high-frequency and in 6 conventionally ventilated newborn infants were investigated. Heart rate, arterial oxygen saturation (SaO(2)), mean blood pressure (MABP), and transcutaneous carbon dioxide tension (TcpCO(2)) were monitored continuously. In both groups, a marked decrease in heart rate, SaO(2) and in cO(2)Hb, an increase in cHHb, and a variable pattern in the concentration of total hemoglobin were noted during endotracheal suctioning. During suctioning, no statistically significant differences between the two methods of mechanical ventilation could be observed. We conclude that the mode of ventilation had no significant effect on changes in cerebral hemodynamics during endotracheal suctioning.
Assuntos
Encéfalo/fisiologia , Ventilação de Alta Frequência , Recém-Nascido de Baixo Peso , Doenças do Prematuro/fisiopatologia , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho , Sucção , Feminino , Hemodinâmica , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/terapia , Masculino , Estudos Prospectivos , Síndrome do Desconforto Respiratório do Recém-Nascido/terapiaRESUMO
We successfully used high-frequency oscillatory ventilation (HFOV) for treating severe acquired lobar emphysema in two premature newborn infants (birth weights, 1,450 and 1,300 g). After successful weaning from mechanical ventilation for hyaline membrane disease, they needed additional ventilatory support because they developed severe lobar emphysema compressing the residual lung. In both patients, radiographic signs of lobar emphysema disappeared completely after 3 days of HFOV. Diagnosis and follow-up were confirmed by high-resolution computed tomography. We conclude that HFOV may be a useful noninvasive method for treating severe lobar emphysema.
Assuntos
Ventilação de Alta Frequência , Doenças do Prematuro/terapia , Enfisema Pulmonar/terapia , Ventilação de Alta Frequência/métodos , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/diagnóstico , Doenças do Prematuro/fisiopatologia , Masculino , Enfisema Pulmonar/diagnóstico , Enfisema Pulmonar/fisiopatologia , Tomografia Computadorizada por Raios XRESUMO
The adult respiratory distress syndrome (ARDS) in children has a very poor prognosis with a mortality risk of between 55 and 85%, in spite of improvements due to the introduction of positive endexpiratory pressure ventilation. We describe the clinical course of a not yet 3 year-old boy with severe ARDS following near-drowing. Treatment with exogenous surfactant and high frequency oscillatory ventilation, a well-established procedure in neonatology, was responsible for the favorable outcome. The high cost of surfactant therapy, however, is the main limiting factor for this kind of treatment in children beyond the neonatal period, but it may be the last therapeutic resort in the management of severe ARDS.
Assuntos
Ventilação de Alta Frequência , Afogamento Iminente/terapia , Surfactantes Pulmonares/administração & dosagem , Síndrome do Desconforto Respiratório/terapia , Pré-Escolar , Cuidados Críticos , Humanos , Masculino , Afogamento Iminente/complicações , Oxigênio/sangue , Radiografia , Síndrome do Desconforto Respiratório/diagnóstico por imagemRESUMO
Survival after corrective surgery of pulmonary atresia was associated with low right ventricular pressure, indicating normal pulmonary vascular resistance. Therefore increased fractional inspiratory oxygen concentration, inhaled nitric oxide and intravenous prostacyclin were considered to be effective measures during postoperative intensive care. In a 20-year-old female, conduit repair and unifocalisation of pulmonary atresia with ventricular septal defect and systemic to pulmonary arterial collaterals were performed despite preexisting one-sided pulmonary hypertension. During the following postoperative period, normal arterial oxygen saturation aimed at by means of a high fractional inspiratory oxygen concentration, resulted in persistent pulmonary oedema despite fluid restriction. After several trials of weaning from artificial ventilation, permissive hypoxemia was eventually successful.
Assuntos
Hipóxia , Atresia Pulmonar/cirurgia , Desmame do Respirador , Adulto , Dióxido de Carbono/sangue , Cuidados Críticos , Feminino , Hemodinâmica , Humanos , Hipertensão Pulmonar/etiologia , Oxigênio/sangue , Cuidados Pós-Operatórios , Período Pós-Operatório , Atresia Pulmonar/complicações , Edema Pulmonar/diagnóstico por imagem , Edema Pulmonar/etiologia , Radiografia Torácica , Resultado do TratamentoRESUMO
Palliative surgery of the hypoplastic left heart syndrome (HLHS), whereby both pulmonary and systemic circulation are restored, was first described by Norwood in 1983. Careful ventilatory and pharmacologic modulation of the ratio of pulmonary to systemic vascular resistance are a crucial part of pre-, peri- and postoperative management. We report our experience in 3 of 7 newborns with HLHS who underwent the Norwood operation. Hemodynamic and respiratory parameters were evaluated retrospectively in these patients and we analysed the influence of diagnostic and therapeutic interventions on the course of disease before and after operation. During prostaglandin therapy two of three patients required mechanical ventilation preoperatively because of pulmonary hyperperfusion. Decreased myocardial contractility, oliguria and increased pulmonary vascular resistance characterized the postoperative course. The management included a careful application of inotropic support when necessary, adaptation of the ventilatory setting in order to modulate pulmonary perfusion and, in addition, institution of peritoneal dialysis. One patient died from staphylococcus aureus and superinfection with respiratory syncytial virus on day 41 after the operation. Maintaining an optimal balance between pulmonary and systemic blood flow is an essential aspect of postoperative management. Serum lactate and central venous oxygen saturation are helpful parameters in monitoring therapeutic measures in these patients. We conclude from our preliminary experience, that the Norwood operation might be an alternative therapeutic approach for newborns with HLHS in whom heart transplantation is not possible.
Assuntos
Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Áustria , Feminino , Seguimentos , Hemodinâmica/fisiologia , Humanos , Síndrome do Coração Esquerdo Hipoplásico/mortalidade , Recém-Nascido , Masculino , Cuidados Paliativos , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Selecting well-qualified employees has become increasingly difficult for employers. Legal complaints citing discrimination and negligent hiring have made interviewers and organizations more vulnerable than ever. Also, predicted declines in the skill levels of employees will continue to make it difficult for interviewers to select applicants who best match job requirements. These difficulties can be traced to a variety of traps that often lead to poor hiring decisions. The authors describe the traps interviewers face and highlight actions that can be taken by interviewers to avoid these traps and to improve the effectiveness of their interviewing and employee selection decisions.
Assuntos
Entrevistas como Assunto/normas , Seleção de Pessoal/métodos , Comunicação , Guias como Assunto , Pessoal de Laboratório Médico/normas , Preconceito , Competência Profissional , Comportamento Social , Estados UnidosRESUMO
Hiring highly qualified employees in today's competitive job market is one of the most important responsibilities for managers. The time, effort, and money that are involved in recruiting, hiring, and training a new employee provide a powerful argument for improving the way we select new employees. Today, many organizations are using team interviews to improve their hiring processes. In this article, we discuss the ways team interviews can enhance selection accuracy and provide a range of benefits for both the candidate and the organization. Specific guidelines on how to use team interviews to make better hiring decisions also are discussed.
Assuntos
Processos Grupais , Entrevistas como Assunto/métodos , Seleção de Pessoal/normas , Guias como Assunto , Seleção de Pessoal/métodos , Técnicas de Planejamento , Estados UnidosRESUMO
Although the involvement of oxidative stress is well documented in the diabetic state, the individual active oxygen species generated have not been demonstrated in animal models of diabetes currently used. Since streptozotocin-induced diabetes mellitus in animals still serves as an animal model of diabetes mellitus, but streptozotocin induces diabetes and generates oxidative stress per se, we decided to study whether aromatic hydroxylation reflecting hydroxyl radical attack was found in three animal models of diabetes mellitus without streptozotocin induction or in streptozotocin-induced diabetes only. For this purpose, we compared lipid peroxidation, aromatic hydroxylation of phenylalanine, glycoxidation in genetically determined diabetic mouse strains db/db and kk, and the diabetic BB rat to these parameters in the streptozotocin-treated rat. Kidney malondialdehyde concentrations, reflecting lipid peroxidation, pentosidine, and Nepsilon-caboxymethyllysine concentrations, reflecting glycoxidation, were significantly elevated in all diabetic groups as compared to their nondiabetic mates. Aromatic hydroxylation was significantly elevated in the streptozotocin-induced diabetic state exclusively. We conclude that biochemical, pathophysiological, and treatment studies in the streptozotocin model of diabetes mellitus may be confounded by the presence of products, reactions, and tissue damage generated by aromatic hydroxylation reflecting hydroxyl radical attack. We suggest it is not the diabetic state but streptozotocin that generates the hydroxyl radical, as reflected by aromatic hydroxylation in this model.
Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Animais , Arginina/análogos & derivados , Arginina/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Modelos Animais de Doenças , Feminino , Frutosamina/sangue , Hidroxilação , Rim/metabolismo , Lisina/análogos & derivados , Lisina/metabolismo , Malondialdeído/metabolismo , Camundongos , Ratos , Ratos Endogâmicos BB , Ratos Sprague-Dawley , Estreptozocina , Tirosina/metabolismoRESUMO
Severe bleeding remains the most common complication of extracorporeal membrane oxygenation (ECMO) following surgical repair of congenital heart defects. We present a case of excessive hemorrhage within the first hours on ECMO support after repair of a type I truncus arteriosus. Bleeding control was achieved by surgical repair following failure of conventional interventions to control hemorrhage despite normalization of laboratory coagulation parameters. Aspects associated with bleeding and bleeding control during extracorporeal circulation after cardiac surgery are discussed.
Assuntos
Oxigenação por Membrana Extracorpórea/efeitos adversos , Hemorragia Pós-Operatória/etiologia , Persistência do Tronco Arterial/cirurgia , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/instrumentação , Transfusão de Eritrócitos , Oxigenação por Membrana Extracorpórea/instrumentação , Feminino , Técnicas Hemostáticas , Humanos , Lactente , Plasma , Transfusão de Plaquetas , Hemorragia Pós-Operatória/prevenção & controle , Hemorragia Pós-Operatória/cirurgia , ReoperaçãoRESUMO
BACKGROUND: Extracorporeal membrane oxygenation (ECMO), originally developed as an artificial replacement for respiratory assistance, is decreasingly used in neonates with respiratory failure. Nevertheless, there is a constant need for this invasive and expensive neonatal treatment modality. INTERVENTION: Review of our experience (80 recent ECMO performances because of circulatory failure) and the literature. RESULTS: In contrary to reduced ECMO performances out of respiratory insufficiency in neonates, ECMO as circulatory support is increasingly used. Neonatal sepsis, pre- and postoperative cardiac failure, combined circulatory and respiratory failure after resuscitation and with congenital diaphragmatic hernia result in a permanent need for ECMO, whenever there are fewer ECMO treatments per year. Nonocclusive pumps, portable devices, small priming volumes and tapered anticoagulation protocols enable survival through ECMO even in virtually hopeless hemodynamic conditions. Special efforts in investigation and prevention of permanent neurological impairment, especially after severe pre-ECMO hypoxia seem to be mandatory. CONCLUSION: ECMO remains an important tool in neonatal and pediatric intensive care. However, the number of ECMO therapies was reduced due to respiratory therapeutic progress, but indications and ECMO technology have changed.
Assuntos
Oxigenação por Membrana Extracorpórea , Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Baixo Débito Cardíaco/complicações , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/instrumentação , Oxigenação por Membrana Extracorpórea/métodos , Hemodinâmica , Hérnia Diafragmática/terapia , Hérnias Diafragmáticas Congênitas , Humanos , Hipóxia/terapia , Recém-Nascido , Oxigenadores de Membrana , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Ressuscitação , Sepse/complicações , Choque/complicações , Taxa de SobrevidaRESUMO
Adrenalin insufficiency associated with adrenal hemorrhage, is a rare complication after cardiac surgery in neonates. A boy suffering from transposition of the great arteries, who had an arterial switch-operation on day three of his life, acquired a bilateral adrenal hemorrhage. Clinically the situation resembled a septic shock. Despite large doses of catecholamines, he continued to have severe arterial hypotension, anuria, and kyperkalemia. The clinical condition did not change, although sepsis specific therapy was initiated. Consequently adrenal insufficiency, as a possible postoperative complication, was considered and prednisolon, initially in a dose of 15 mg/kg/d, was administered. The clinical condition improved dramatically. The diagnosis could be confirmed by ultrasound examination and determination of cortisol and ACTH plasma levels. Adrenal insufficiency was only transitory, adrenal sonography on day 135 returned to normal. The surgical procedure on heart-lung bypass, the obligatory anticoagulation and the perioperative stress have to be considered as pathogenetic factors.
Assuntos
Insuficiência Adrenal/tratamento farmacológico , Hipotensão/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Prednisolona/análogos & derivados , Transposição dos Grandes Vasos/cirurgia , Insuficiência Adrenal/sangue , Hormônio Adrenocorticotrópico/sangue , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Esquema de Medicação , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos , Hidrocortisona/sangue , Hipotensão/sangue , Lactente , Recém-Nascido , Masculino , Complicações Pós-Operatórias/sangue , Prednisolona/administração & dosagemRESUMO
This study was conducted to assess the validity of performing the polymerase chain reaction (PCR) on amniotic fluid for detecting fetal Toxoplasma infection. The primary endpoint was the outcome of the infant at 1 year of age. A prospective, consecutive study was performed in 49 infants born to mothers with primary Toxoplasma infection during pregnancy. PCR determinations of Toxoplasma gondii DNA in amniotic fluid were carried out as part of their prenatal management. Infants were examined at birth, and at 1, 3, 6, 9, and 12 months of age. Nine of 11 infants from pregnancies with positive PCR results proved to be infected based on follow-up serological investigations conducted during the first year of life. Two fetal deaths occurred. All 38 infants with negative PCR results remained uninfected at 1 year of age, irrespective of whether their mothers had received treatment with sulfadiazine/pyrimethamine or spiramycin alone. Psychomotor development was normal in all infants. This follow-up study confirms that PCR performed on amniotic fluid is a useful method for identification or exclusion of fetal Toxoplasma infection. Treatment of infected pregnant women and - in the event of a positive PCR result subsequent treatment of their infants is associated with a favorable outcome.
Assuntos
Líquido Amniótico/parasitologia , DNA de Protozoário/análise , Reação em Cadeia da Polimerase/métodos , Complicações Parasitárias na Gravidez/diagnóstico , Toxoplasmose Congênita/diagnóstico , Toxoplasmose/diagnóstico , Adulto , Animais , Antibacterianos/uso terapêutico , Antiprotozoários/uso terapêutico , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Gravidez , Complicações Parasitárias na Gravidez/tratamento farmacológico , Diagnóstico Pré-Natal , Estudos Prospectivos , Pirimetamina/uso terapêutico , Reprodutibilidade dos Testes , Espiramicina/uso terapêutico , Sulfadiazina/uso terapêutico , Toxoplasma/isolamento & purificação , Toxoplasmose/tratamento farmacológico , Toxoplasmose Congênita/parasitologiaRESUMO
In posthypoxic circulatory failure, pulsatility of flow generated by mechanical support devices significantly influences outcome. Pneumatically driven assist devices can create highly pulsatile flow, but need large graft cannulas implanted by thoracotomy in children and neonates. Emergency application is therefore hindered. We conducted an in vitro study using neonatal mock circulation (NMC) to test whether an extracorporeal membrane oxygenation (ECMO) system driven by a commercially available pneumatic assist device also can be operated through commonly used neonatal neck vessel cannulas. Using the pneumatically operated Medos ventricular assist device (VAD) 10 ml ventricle along with the Jostra M8/HEC40 oxygenator/heat exchanger, a neonatal ECMO system was assembled and connected to the NMC by means of commercially available neonatal neck vessel cannulas. Effective ECMO flow, combined circulation flow, and circulation pressures were measured during various working settings (ventricle driving pressures [systolic/diastolic (mbar)]: low: +100/-25, moderate: +200/-50, high: +300/-99) and loading conditions (device working against 0, 50, and 100% native circulation flow). Additionally, maximum possible ECMO flow through various sizes of neonatal ECMO cannulas and resulting pressure gradients were assessed. High pressure settings were necessary to achieve 100 ml/kg/min pulsatile circulation flow in case of zero native circulation. With residual 30% native circulation flow, 100 ml/kg/min pulsatile circulation flow could be established by moderate pressure settings. Low preload or high systemic vascular resistance reduced ECMO flow markedly. We concluded that in the described setting a pneumatically driven neonatal ECMO system could be operated even through commonly used neonatal neck vessel cannulas. It was necessary to accept partial emptying of the artificial ventricle and tapering of driving pressures with increasing native circulation.