RESUMO
PURPOSE: Adult-onset xanthogranuloma (AOX) of the corneoscleral limbus is a rare inflammatory condition of unknown aetiology. Similar to limbal juvenile xanthogranuloma (JXG), it presents as a growing mass at the corneoscleral junction. Limbal AOX and JXG can lead to sight-threatening complications if not managed in a timely manner. This systematic review summarises the main clinical and histopathological features of limbal AOX/JXG and discusses the management of this uncommon disease. METHODS: We performed a literature search in the MEDLINE database for all historical entries, using the search terms "limbus", "limbal" and "xanthogranuloma", and retrieved all articles reporting on limbal xanthogranuloma. After refining the search to articles relevant to limbal AOX, we were able to identify ten adult cases of limbal AOX and compare those with all reported cases of limbal JXG. RESULTS: Clinically, AOX usually presents as an isolated smooth, yellowish, dome-shaped nodule at the corneoscleral junction, similar to an ocular presentation of JXG, with which it also shares similar histopathological features. CONCLUSION: Limbal JXG and AOX may represent the same disease entity. Diagnosis relies on the clinical presentation, pathology and immunohistochemical profile. Spontaneous regression is unlikely, and thus prompt surgical intervention should be considered to prevent sight-threatening complications. Xanthogranuloma should be included in the differential diagnosis of corneoscleral limbal masses in patients of all age groups.
Assuntos
Doenças da Córnea , Granuloma , Limbo da Córnea , Xantogranuloma Juvenil , Xantomatose , Adolescente , Adulto , Idoso , Pré-Escolar , Doenças da Córnea/diagnóstico , Doenças da Córnea/epidemiologia , Doenças da Córnea/terapia , Feminino , Granuloma/diagnóstico , Granuloma/epidemiologia , Granuloma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Xantogranuloma Juvenil/diagnóstico , Xantogranuloma Juvenil/epidemiologia , Xantogranuloma Juvenil/terapia , Xantomatose/diagnóstico , Xantomatose/epidemiologia , Xantomatose/terapia , Adulto JovemAssuntos
Recém-Nascido Prematuro , Triagem Neonatal/métodos , Retinopatia da Prematuridade/diagnóstico , Seleção Visual/métodos , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Triagem Neonatal/normas , Guias de Prática Clínica como Assunto/normas , Seleção Visual/normasRESUMO
Histological severity is often mandatory for the management of HBeAg-negative chronic HBV patients. We evaluated the performance of transient elastography (TE) in this setting. We included 357 untreated HBeAg-negative patients with ≥ 1 reliable liver stiffness measurement (LSM-kPa) by TE: 182 inactive carriers with HBV-DNA < 2000 (n = 139) or 2000-19 999 IU/mL (n = 43) and 175 patients with chronic hepatitis B (CHB). In carriers, HBV-DNA > 2000 and/or LSM > 6.5 were considered as biopsy indications. LSMs did not differ between carriers with low and high viremia, but were lower in carriers than in patients with CHB (5.8 ± 1.7 vs 9.0 ± 5.6, P < 0.001) offering moderate differentiation between these two groups (AUROC: 0.705). LSMs did not change significantly in carriers after 16 (12-24) months. In carriers with a liver biopsy, Ishak's staging scores were similar between cased with low and high viremia but higher in cases with LSM > 6.5 than ≤ 6.5 kPa. Moderate fibrosis (stages: 2-3) was detected in 0/10 carriers with only HBV-DNA > 2000 IU/mL, 2/10 (20%) carriers with only LSM > 6.5 and 5/10 (50%) carriers with both HBV-DNA > 2000 and LSM > 6.5 (P = 0.009). In patients with CHB, LSMs correlated significantly with grading and staging scores and offered excellent accuracy for ≥ moderate, ≥ severe fibrosis or cirrhosis (AUROC ≥ 0.919-0.950). TE can be helpful for the noninvasive assessment of HBeAg-negative chronic HBV patients. In conclusion, LSMs offer excellent accuracy for fibrosis severity in HBeAg-negative patients with CHB and can identify carriers with high risk of moderate fibrosis, which may be present in up to 35% of carriers with LSM > 6.5 kPa and 50% of carriers with LSM > 6.5 kPa and HBV-DNA > 2000 IU/mL.
Assuntos
Técnicas de Imagem por Elasticidade/métodos , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/complicações , Cirrose Hepática/diagnóstico , Adulto , Idoso , Feminino , Hepatite B Crônica/virologia , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de DoençaRESUMO
Postintubation damage is a potential hazard in any patient intubated with an oral or nasal endotracheal tube or with a tracheostomy tube for ventilatory support. Postintubation tracheal stenosis may be fatal unless it is recognized and treated promptly. This paper reviews the important features of diagnosis and treatment of postintubation tracheal stenosis.
Assuntos
Intubação Intratraqueal/efeitos adversos , Estenose Traqueal/etiologia , Adulto , Feminino , Humanos , Estenose Traqueal/diagnóstico , Estenose Traqueal/terapia , Traqueostomia/efeitos adversosRESUMO
Neurological side effects associated with cyclosporine immunosuppressive therapy are generally believed to occur with CsA blood concentrations above the therapeutic range. The effects of high blood CsA levels on cerebral hemodynamics, metabolism, and electrophysiologic activity were studied in acute (no CsA prior treatment) and chronic (with CsA prior treatment) dogs. In acute animals, when parenteral CsA (10 mg/kg or 25 mg/kg) was administered intravenously (CsA blood level 2000-22,000 ng/ml), slight but significant time-dependent decreases in cerebral blood flow (CBF), prolongation of absolute latencies of somatosensory-evoked potential (SSEP), and brainstem auditory-evoked responses (BAER) were noted. In the CsA chronically administered animals (oral CsA 25 mg/kg/24 hr for 14 days, CsA blood level 1077 ng/ml), baseline cerebral physiologic parameters were normal, and the cerebral responses to further administration of CsA (25 mg/kg, CSA blood level 56,000 ng/ml) intravenously were similar to those of the acute animals. Animals given Cremophor EL, the solvent for parenteral CsA preparation, showed similar cerebral responses to those observed in animals given CsA. Thus this study showed that CsA, regardless of the dose given, whether chronically or acutely administered, or the solvent for CsA all induced similar cerebral physiologic responses. We suggest that the cerebral physiologic and functional changes associated with parenteral CsA administration were small and were likely caused by its solvent, Cremophor EL, rather than CsA itself. Furthermore on the basis of our results, it is unlikely that high blood CsA per se can account for neurological side effects that occur in immunosuppressed patients.
Assuntos
Encéfalo/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Ciclosporina/farmacologia , Animais , Ciclosporina/sangue , Ciclosporina/líquido cefalorraquidiano , Cães , Potenciais Evocados Auditivos do Tronco Encefálico/efeitos dos fármacos , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Feminino , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacosRESUMO
To characterize the neural and vasoactive mediators of pulmonary vasoconstriction and determine whether the beneficial effect of isoproterenol could be mimicked by other agents that increase cyclic adenosine monophosphate, heart and lung organ blocks were harvested from calves and studied in a normothermic autoperfusion circuit. In the experimental protocol, measurements were obtained (A) after sternotomy but before autoperfusion (in vivo); (B) during stimulation of in vivo control with tert-butyl hydroperoxide (t-BuOOH), a lipid peroxide; (C) after cannulation and institution of in situ autoperfusion (innervated preparation); (D) following denervation and explanation (ex vivo); (E) during stimulation of ex vivo preparation with t-BuOOH; and (F,G) after administration of isoproterenol, aminophylline and prostaglandin E1 to the ex vivo preparation with (time G) and without (time F) stimulation using t-BuOOH. Plots of transpulmonary pressure gradient versus cardiac output were generated for each animal, and an index of pulmonary vascular resistance was obtained from the slope of the linear relationship. Blood samples were collected for measurement of thromboxane-B2, 6-keto-prostaglandin-F1 alpha, and complement activation products C3a and C5a. Pulmonary vasoconstriction occurred during in situ autoperfusion prior to denervation and increased further following denervation and ex vivo autoperfusion; vasoconstriction correlated with increased levels of circulating vasoactive mediators. The pulmonary vasoconstrictor response was greater in the denervated vascular bed compared with the innervated state. All agents reduced postexplant pulmonary vasoconstriction. We conclude that agents that increase cyclic AMP modulate the pulmonary vasoconstrictor response and thus may enhance lung preservation in the autoperfusion model as well as with other current preservation methods.
Assuntos
Transplante de Coração-Pulmão/fisiologia , Coração , Pulmão/fisiologia , Preservação de Órgãos , Alprostadil/farmacologia , Aminofilina/farmacologia , Animais , Ácido Araquidônico/metabolismo , Gasometria , Bovinos , Ativação do Complemento , Complemento C3a/análise , AMP Cíclico/análise , Denervação , Feminino , Hemodinâmica , Isoproterenol/farmacologia , Contagem de Leucócitos , Perfusão , Artéria Pulmonar/inervação , Artéria Pulmonar/fisiologia , Resistência Vascular , Vasoconstrição/imunologiaRESUMO
The autoperfused working heart-lung preparation has been used for extended cardiopulmonary preservation for transplantation. However, acute lung injury and failure of the preparation can result from pulmonary hypertension, which previous investigators have linked to denervation. We studied the neural and vasoactive mediators of pulmonary vasoconstriction during normothermic autoperfusion of the heart and lungs from 13 calves. Pulmonary vascular resistance was quantitated by multipoint pulmonary artery pressure/flow plots generated by incremental reduction in venous return at three times: A, after sternotomy but before autoperfusion (control); B, during in situ autoperfusion (innervated heart-lung preparation); and C, after explanation (denervated heart-lung preparation). During hemodynamic measurements, left atrial blood samples were obtained for measurement of thromboxane B2, 6-keto-prostaglandin-F1 alpha, and complement activation products C3a and C5a. Results show that pulmonary hypertension in the autoperfused working heart-lung preparation begins during autoperfusion before denervation and may be related to complement activation and to increased levels of circulating thromboxane B2 and 6-keto-prostaglandin F1 alpha (both the absolute levels and the ratio of thromboxane B2 to 6-keto-prostaglandin F1 alpha). After denervation, both prostaglandin intermediates were markedly increased, but their ratio was not significantly affected. These data suggest that there is an initial stage of pulmonary vasoconstriction at the onset of autoperfusion that is accompanied by increased circulating levels of vasoactive mediators and that denervation further contributes to this response.
Assuntos
6-Cetoprostaglandina F1 alfa/sangue , Coração , Pulmão , Preservação de Órgãos/métodos , Circulação Pulmonar , Tromboxano A2/sangue , Tromboxano B2/sangue , Animais , Pressão Sanguínea , Bovinos , Ativação do Complemento , Denervação/efeitos adversos , Hemodinâmica , Contagem de Leucócitos , Contagem de PlaquetasRESUMO
Quantitative analysis of biplane ventriculograms, including calculation of the end-systolic pressure/volume ratio, was used to define left ventricular systolic performance in 10 normal subjects, 10 patients with symptomatic subacute (less than 6 months' duration) mitral regurgitation, and 18 patients with symptomatic chronic mitral regurgitation. Left ventricular volume, mass, and systolic function were similar for patients with subacute and with chronic mitral regurgitation, suggesting that some patients with recent-onset nonischemic mitral regurgitation have partial adaptation to chronic valve insufficiency prior to their symptomatic event. Rate of development of left ventricular wall stress in early systole was increased in subacute mitral regurgitation compared with chronic mitral regurgitation and normal subjects. Duration of symptoms did not correlate with degree of ventricular adaptation to mitral regurgitation, and end-systolic indices of left ventricular performance did not predict early postoperative clinical response to valve replacement or repair.
Assuntos
Coração/fisiopatologia , Insuficiência da Valva Mitral/fisiopatologia , Adaptação Fisiológica , Débito Cardíaco , Volume Cardíaco , Cinerradiografia , Feminino , Coração/diagnóstico por imagem , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , PressãoRESUMO
Twenty-seven patients underwent reoperation because of thrombotic obstruction of a disc-type cardiac valve prosthesis. Preoperative clinical features included effort dyspnea in 81%, new-onset angina in 44%, a new murmur in 89%, and an abnormal opening or closing sound associated with the prosthetic valve in 56%. Symptoms were present for 1 week or more before reoperation in 86%, although many patients were referred only after acute exacerbation of heart failure and development of pulmonary edema. Noninvasive studies confirmed prosthetic valve malfunction in only 33%, but cardiac catheterization documented thrombotic obstruction in all 15 patients in whom it was performed. In 14 of the 27 patients, prothrombin time was in the therapeutic range at the time of admission. Prompt reoperation for valve replacement or thrombectomy was performed with an operative mortality of 11%, and long-term outcome was satisfactory in all but 1 hospital survivor. These findings emphasize the importance of considering the diagnosis of thrombosed heart valves in patients with mechanical heart valves who are seen with nonspecific symptoms.
Assuntos
Próteses Valvulares Cardíacas/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Trombose/diagnóstico , Trombose/cirurgia , Adulto , Idoso , Valva Aórtica , Cateterismo Cardíaco , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese , Reoperação , Valva TricúspideRESUMO
Twenty-three dairy calves underwent heart-lung allotransplantation after donor organs were procured using either donor core-cooling through cardiopulmonary bypass (CPB) or pulmonary artery flush (PAF) to assess which method provides optimal graft preservation. In Groups 1 (control) and 2, donors were cooled to 15 degrees C on CPB and organs were either immediately transplanted (Group 1) or stored in saline solution (4 degrees C) for 4 hours (Group 2) prior to transplantation. In Group 3, donors were pretreated with prostaglandin E1 prior to PAF with modified Euro-Collins solution. Organs were stored in saline solution (4 degrees C) for 4 hours and were then transplanted. Acute cardiopulmonary function following transplantation was assessed by the ratio of end-systolic pressure to end-systolic dimension, extravascular lung water (EVLW), lung compliance, arterial oxygenation, and lung biopsy. Cardiac function after the transplantation procedure was similar in all groups, but EVLW values and lung biopsy scores were worse after PAF. Arterial O2 tension appeared lower after PAF, but not significantly so. Core-cooling provides superior static preservation and thus improved graft function in the acute bovine model.
Assuntos
Transplante de Coração , Transplante de Coração-Pulmão , Transplante de Pulmão , Preservação de Órgãos/métodos , Animais , Ponte Cardiopulmonar , Bovinos , Temperatura Baixa , Testes de Função CardíacaRESUMO
The autoperfused working heart-lung (AWHL) preparation may provide successful cardiopulmonary preservation for up to 6 hours before transplantation. To determine whether the addition of metabolic substrate could prolong myocardial and pulmonary preservation in the AWHL model, 20 heart-lung blocks were harvested from calves. The brachiocephalic artery and superior vena cava were cannulated with extracorporeal tubing and connected to an elevated reservoir allowing total perfusion through a normothermic autoperfusion circuit. Eight heart-lung blocks were given dextrose and ribose followed by a continuous dextrose-insulin infusion, whereas the remaining 12 specimens received no additional substrates. Myocardial function was assessed by sonomicrometric techniques and pulmonary preservation evaluated by arterial oxygenation on 100% inspired oxygen, static lung compliance, and serial lung biopsies. The addition of substrate prolonged organ survival from 5 +/- 1 to 12 +/- 3 hours (p less than 0.001) and was associated with preservation of myocardial and pulmonary function. Application of substrate addition to the AWHL model will extend the interval of preservation for both heart and heart-lung transplantation.
Assuntos
Coração , Pulmão , Preservação de Órgãos/métodos , Animais , Bovinos , Glucose/farmacologia , Coração/fisiologia , Técnicas In Vitro , Insulina/farmacologia , Pulmão/fisiologia , Perfusão , Ribose/farmacologia , Sobrevivência de Tecidos/efeitos dos fármacosRESUMO
Uncontrolled pulmonary hypertension during autoperfusion of the heart and lungs for preservation has been described, and it may result in extensive pulmonary injury and occasional early failure of the preparation. In order to investigate the neurohumoral mediators of the vasoconstrictor response in the pulmonary circulation of the autoperfused working heart-lung preparation, heart-lung organ blocks were harvested from calves, placed in a normothermic autoperfusion circuit, and studied. Effects of beta-adrenergic stimulation with isoproterenol, nonspecific vasodilatation with nitroglycerin, alpha-adrenergic blockade with phentolamine, phospholipase A2 inhibition with methylprednisolone, cyclooxygenase inhibition with indomethacin, and white blood cell depletion were independently evaluated. Untreated animals, pre- and postexplant, served as controls. Multipoint pulmonary vascular pressure-cardiac output plots were constructed for each animal. An index of pulmonary vascular resistance was obtained from the linear relation: mean pulmonary artery pressure minus pulmonary capillary wedge pressure divided by cardiac output. An intense flow-dependent pulmonary vasoconstrictor response was confirmed to exist in the denervated bovine autoperfused working heart-lung preparation. Isoproterenol afforded better protection against this response than the other agents studied. White blood cell depletion reduced postexplant pulmonary vasoconstriction, implying that circulating polymorphonuclear leukocytes mediate the response in the autoperfused working heart-lung preparation. White blood cell depletion and the administration of selected pharmacologic agents provide modalities for regulating the pulmonary vasoconstrictor response, and thus may enhance lung preservation in the autoperfusion model.
Assuntos
Transplante de Coração , Transplante de Coração-Pulmão , Transplante de Pulmão , Neurotransmissores/fisiologia , Preservação de Órgãos/métodos , Perfusão/métodos , Vasoconstrição , Animais , Gasometria , Bovinos , Coração/fisiologia , Indometacina/farmacologia , Isoproterenol/farmacologia , Leucopenia/fisiopatologia , Pulmão/irrigação sanguínea , Pulmão/fisiologia , Metilprednisolona/farmacologia , Nitroglicerina/farmacologia , Fentolamina/farmacologia , Pressão Propulsora Pulmonar/efeitos dos fármacos , Transplante Autólogo/métodos , Vasoconstrição/efeitos dos fármacosRESUMO
In order to determine whether a no-flush, core-cooling technique could provide extended heart-lung preservation, we placed donor calves on cardiopulmonary bypass and instituted rapid cooling to 15 degrees C during the continuous infusion of isoproterenol. The heart and lungs were harvested after the administration of a cardioplegic solution through the aortic root. In the control group (N = 5), heart and lungs were orthotopically allotransplanted immediately. In the preserved group (N = 5), heart and lungs were similarly excised but were stored in a normal saline bath at 4 degrees C for approximately 4 hours and then transplanted. Both groups received isoproterenol during reperfusion and were studied for 6 hours after implantation. A load independent analysis of myocardial function was done by determining with a sonomicrometer the ratio of the end-systolic pressure to the end-systolic dimension. Pulmonary preservation was evaluated by measurement of extravascular lung water with a double-indicator dilution method, arterial oxygenation on 100% inspired oxygen, and serial lung biopsies. Myocardial and pulmonary function after 4 hours of static preservation was found to be similar to controls. No-flush, core-cooling with cardiopulmonary bypass provides adequate cardiorespiratory function after acute bovine heart-lung allotransplantation. With the use of this technique, successful extended cold ischemic cardiopulmonary preservation for heart-lung transplantation may be achieved.
Assuntos
Ponte Cardiopulmonar/métodos , Transplante de Coração , Transplante de Coração-Pulmão , Hipotermia Induzida/métodos , Transplante de Pulmão , Preservação de Órgãos/métodos , Animais , Pressão Sanguínea , Água Corporal/análise , Débito Cardíaco , Bovinos , Coração/fisiologia , Parada Cardíaca Induzida , Isoproterenol/administração & dosagem , Pulmão/análise , Pulmão/patologia , Oxigênio/sangue , Volume Sistólico , Doadores de TecidosRESUMO
The effects of preserving the heart and lungs with an autoperfused working heart-lung preparation or simple hypothermia via cardiopulmonary bypass were studied in 18 dairy calves that had combined heart-lung transplantation. Group 1 (n = 6) served as the control group in which animals were cooled with cardiopulmonary bypass and immediately had allotransplantations. In group 2 (n = 6), cardiopulmonary function was maintained in the autoperfusion circuit for 4 hours, followed by transplantation. In group 3 (n = 6), the organs were harvested after cooling by cardiopulmonary bypass, stored in cold (4 degrees C) saline solution for 4 hours, and then transplanted. Cardiopulmonary function was compared between the three groups for 6 hours after implantation. Cardiac function was determined by the ratio of the end-systolic pressure to end-systolic dimension. Pulmonary function was evaluated by the measurement of extravascular lung water, arterial oxygenation on 100% inspired oxygen static lung compliance, and histologic lung injury score. All measurements in groups 2 and 3 were similar to those of the control group at 6 hours after implantation. One may use either the hypothermic cardiopulmonary preservation method after cardiopulmonary bypass or the autoperfused working heart-lung preparation for distant organ procurement and expect adequate cardiopulmonary function after transplantation.
Assuntos
Ponte Cardiopulmonar , Transplante de Coração , Transplante de Coração-Pulmão , Hipotermia Induzida , Transplante de Pulmão , Preservação de Órgãos/métodos , Perfusão/métodos , Animais , Bovinos , Espaço Extracelular , Coração/fisiologia , Pulmão/fisiologia , Oxigênio/sangueRESUMO
Myocardial and pulmonary preservation can be prolonged in the autoperfused working heart-lung (AWHL) preparation by metabolic substrate enhancement. However, uncontrolled pulmonary hypertension following denervation may result in extensive lung injury and occasional early failure of the preparation. To determine whether cardiopulmonary preservation could be reliably extended without development of pulmonary hypertension, six heart-lung blocks were harvested from calves, placed in a normothermic AWHL circuit, and studied. Continuous infusions of isoproterenol and dextrose/insulin were administered for the duration of the preparation. Thirteen heart-lung preparations received neither isoproterenol nor metabolic substrate and served as controls. Myocardial function was assessed by sonomicrometric techniques and pulmonary preservation was evaluated by extravascular lung water, arterial oxygenation on 100% inspired oxygen, static lung compliance, and pulmonary vascular resistance. Pulmonary hypertension developed in the control group and these animals did not survive beyond 7.5 hours. The addition of isoproterenol and metabolic substrate increased organ survival from 4.8 +/- 0.4 to 18.0 +/- 1.4 hours (p = 0.0001) and significantly reduced postexplant pulmonary vasoconstriction (p less than 0.05). Addition of isoproterenol and metabolic substrate to the AWHL model prolonged support of cardiorespiratory function and provided a reliable method for distant procurement in heart-lung transplantation.
Assuntos
Transplante de Coração , Transplante de Coração-Pulmão , Transplante de Pulmão , Preservação de Órgãos/métodos , Perfusão/métodos , Animais , Bovinos , Denervação , Isoproterenol/administração & dosagem , Isoproterenol/farmacologia , Pulmão/inervação , Complacência Pulmonar , Oxigênio/sangue , Artéria Pulmonar/fisiologia , Fatores de Tempo , Resistência VascularRESUMO
This study was done to determine whether core-cooling could provide extended cardiopulmonary preservation and if reimplantation could be simulated and evaluated in the ex vivo autoperfused working heart-lung model. Twenty calves were divided into four groups and placed on cardiopulmonary bypass and rapidly cooled to 15 degrees C. Control heart and lungs were harvested after administration of cardioplegia through the aortic root and were subsequently resuscitated in the autoperfused working heart-lung circuit (group 1) or were orthotopically allotransplanted (group 2). Preserved heart and lungs were similarly excised but stored in a normal saline solution bath at 4 degrees C for 4 hours and then were resuscitated in the autoperfusion circuit (group 3) or were orthotopically allotransplanted (group 4). All groups received isoproterenol during explantation and reperfusion and were studied for 4 hours. Myocardial function was assessed by sonomicrometric techniques, and pulmonary preservation was evaluated by measurements of extravascular lung water, arterial oxygen tension on 100% inspired oxygen, and pulmonary vascular resistance. Cardiorespiratory function after 4-hour static preservation was similar in all four groups except that the arterial oxygen tension in group 1 was lower compared with group 3. Core-cooling on cardiopulmonary bypass without pulmonary artery flushing results in cold ischemic heart-lung preservation, comparable to other currently used modalities. In addition, reperfusion in the ex vivo autoperfusion circuit provides a simplified model to assess the adequacy of cardiopulmonary preservation techniques.
Assuntos
Ponte Cardiopulmonar , Temperatura Baixa , Coração , Pulmão , Preservação de Órgãos/métodos , Animais , Água Corporal/metabolismo , Bovinos , Circulação Coronária , Feminino , Transplante de Coração , Transplante de Coração-Pulmão , Pulmão/metabolismo , Transplante de Pulmão , Preservação de Órgãos/instrumentação , Oxigênio/sangue , Pressão Parcial , Circulação Pulmonar , Resistência VascularRESUMO
Thromboembolic complications continue to be potential hazards in patients with prosthetic heart valves, and cerebral infarct and transient neurologic deficits as a result of embolism are the most common manifestations. Actual thrombotic obstruction of the valve occurs less frequently but is often fatal unless it is recognized and treated promptly. Tilting disk prostheses, such as the Björk-Shiley valve, seem to be associated with a higher incidence of thrombosis than other prosthetic designs. In this article, we review the important features of diagnosis and treatment of thrombotic occlusion of prosthetic valves.