João José Carneiro

Divertículo do esôfago análise de 24 pacientes portadores do divertículo de Zenker

O diverticulo de Zenker e um diverticulo de pulsao localizado na transicao faringo-esofagica. Trata-se de uma patologia bastante rara, sendo a etiologia de 0,11% de 20000 exames radiologicos de esofago. Incide mais em pacientes acima de 60 anos e afeta mais homens, na proporcao de 4:1 segundo a literatura. Dos 24 pacientes operados, 23 diverticulos foram a esquerda e o unico caso a direita tinha antecedentes de uma cervicotomia do mesmo lado. Apresentamos inclusive um caso de mae e filho com esta doenca. Apresentamos a nossa experiencia no referente a clinica, diagnostico e resultados cirurgicos em 24 casos operados.

Uso de cateteres venosos totalmente implantados para nutrição parenteral: cuidados, tempo de permanência e ocorrência de complicações infecciosas

Cateteres venosos totalmente implantados sao utilizados em pacientes com sindrome do intestino curto, pararealizar o suporte nutricional parenteral, o qual mantem estes pacientes vivos, pois fornece-lhes nutrientesque sao absorvidos pela via digestiva. No entanto, estes cateteres nao sao isentos de complicacoes. Asinfeccoes relacionadas aos cateteres venosos sao as complicacoes mais temidas e sua incidencia varia de 3%a 20%, aumentando em pacientes mais graves. O objetivo do presente estudo e descrever as complicacoesinfecciosas em pacientes recebendo nutricao parenteral por meio de cateteres venosos totalmente implantados.Tais cateteres sao utilizados pela Divisao de Nutricao Clinica do Hospital das Clinicas da Faculdade de Medicinade Ribeirao Preto, Universidade de Sao Paulo, para realizar o suporte nutricional parenteral em pacientessubmetidos a resseccoes extensas de intestino delgado. Foram avaliadas as complicacoes infecciosas ocorridascom 21 cateteres, implantados em 16 pacientes. O tempo de permanencia dos cateteres foi de 768±664,3dias (mediana 529 dias) e a taxa de infeccao foi de 0,029 infeccoes/paciente/ano, resultados que se comparamas taxas de infeccao observadas em paises desenvolvidos. Concluiu-se que os cuidados observados no manuseiodestes cateteres foram de fundamental importância para diminuir a incidencia de infeccao nestes pacientes.

The role of magnesium in the endothelial dysfunction caused by global ischemia followed by reperfusion: in vitro study of canine coronary arteries

Objective—To study the role of magnesium in the endothelial dysfunction of canine coronary arteries caused by cardiopulmonary bypass (CPB) global ischemia followed by reperfusion. Design—Segments of canine coronary arteries were suspended in organ chambers to measure isometric contraction by prostaglandin F 2α , and relaxed by acetylcholine (ACh), sodium fluoride (NaF), calcium ionophore (A 23187 ) and sodium nitroprusside (SNP) in crescent concentrations. The investigation protocol had groups with six dogs: CONTROL group (without CPB), CPB group (105 min of CPB without aortic cross‐clamping), ISCH group (45 min of CPB with aortic cross‐clamping), ISCH/REP group (45 min of aortic cross‐clamping followed by 60 min of reperfusion). The coronary relaxations were evaluated with (phase I), without (phase II) and restored magnesium (phase III) to the organ bath. Results—The presence of magnesium in the organ bath was associated with the greater relaxation in response to agonists of the nitric oxide production. The removal of magnesium from the organ bath was associated with the reduction in the intensity of vessel relaxation. The magnesium restoration to the organ bath was associated with the additional reduction in the intensity of relaxation with the exception of NaF that allowed re‐acquisition of the relaxation observed in the presence of magnesium. Conclusion—This in vitro study demonstrates that magnesium ion favorably influences the nitric oxide production by the coronary endothelium, attenuating the endothelial dysfunction caused by global ischemia followed by reperfusion.

Hidratação e equilíbrio ácido-base em pacientes cirúrgicos

Estudou-se a influencia da hidratacao em 30 pacientes submetidos a cirurgia de pequeno e grande porte. Os pacientes foram divididos em grupos de 5 conforme o porte cirurgico e o tipo de hidratacao: restricao hidrica, segundo o balanco diario e sobrecarga hidrossalina. As alteracoes mais relevantes do equilibrio acido base foram: pre-operatorio - alcalose respiratoria; pos-operatorio imediato - acidose respiratoria; 1o, 2o e 3o dias de pos-operatorio - alcalose respiratoria, metabolica ou mista. Os metodos de hidratacao com restricao hidrica ou segundo o balanco nao afetaram o equilibrio acido-base, enquanto que a sobrecarga hidrossalina reduziu de modo significativo a incidencia de alcalose metabolica no pos-operatorio.

Disfunção endotelial após isquemia global e reperfusão em cirurgia cardíaca com circulação extracorpórea: estudo do papel do magnésio em artérias coronarianas caninas

INTRODUCTION: Hypomagnesemia and ischemia followed by reperfusion often occur in cardiac surgery. Both of them are associated with endothelial dysfunction which interfers negatively with patient evolution. Phisiopatology of these disturbances is similar and involves G-proteins dysfunction. OBJECTIVE: The present study focuses on the endothelial dysfunction consequent to the lesion resulting from global ischemia followed by reperfusion and the potential protective influence of magnesium on the endothelium functional integrity in isolated coronaries of dogs. METHOD: Segments of canine coronary arteries were suspended in organ chambers to measure isometric force. Endothelial dysfunction was evaluated by the ability of these segments to produce nitric oxide changing the initial isometric force. Four groups with six dogs in each one were selected: SEM CEC (control), CEC (110 minutes of perfusion without ischemia), ISQ (45 minutes of ischemia), ISQ/REP (45 minutes of ischemia followed by 60 minutes of reperfusion). The magnesium action was evaluated in three different phases: I (organ chambers with magnesium), II (organ chambers without magnesium) and III (organ chambers with restored magnesium). Three pharmacological agonists were used which represented the main steps involved in the nitric oxide production: the membrane receptor of the endothelial cell - acetylcholine (ACh); transduction of the signal between the receptor and the intracellular processes through the G-protein - sodium fluoride (NaF); liberation of intracellular stocks of calcium - calcium ionophore (A23187). The study of endothelial function was combined with the evaluation of smooth muscle activity dependent on GMPc - sodium nitroprusside (NPS). RESULTS: The major findings of this investigation were as follows: 1) presence of magnesium in priming seemed to attenuate the endothelial dysfunction caused by global ischemia followed by reperfusion; 2) presence of magnesium in the organ chamber (phase I) was associated with the greatest relaxation in response to agonists of the nitric oxide production; 3) removal of magnesium in the organ chamber (phase II) was linked to the reduction in the relaxation intensity in response to agonists of the nitric oxide production; 4) the magnesium restoration to the organ chamber (phase III) allowed restoration of the relaxation observed in the phase I, only in response to the direct stimulation of the G-proteins. For the rest of the remaining agonists, the restoration was associated with the additional reduction in the relaxation intensity; 5) the smooth muscle received the influence of the magnesium concentration in the organ chamber. CONCLUSION: It was concluded that magnesium favorably influences the nitric oxide production by the coronary endothelium attenuating the endothelial dysfunction caused by global ischemia followed by reperfusion.

Cardioplegia sanguínea anterógrada intermitente normotérmica e hipotérmica: estudo comparativo em coraçöes agudamente isquêmicos de coelhos

OBJECTIVE: This in vitro investigation aimed to compare the degree of myocardial preservation afforded by intermittent anterograde normothermic vs hypothermic blood cardioplegia, infused at 20 minutes intervals, in acutely ischemic rabbit hearts. METHODS: Myocardial concentration of glycogen and lactate, as well as mitochondrial respiration and left ventricular function (dP/dtmax ) were analyzed. The study was divided into two phases, one without (Phase I) and one with (Phase II) a period of reperfusion following the last dose of cardioplegia. Each phase included 4 groups. In Phase I, hearts sent for metabolic analysis immediately after being excised comprised the Control group. After being subjected to global normothermic ischemia for 20 min, hearts were sent for biochemical analysis (Ischemic group), or else received 4 doses of cardioplegia at 37° C (Normothermic group) or at 17° C (Hypothermic group) before biochemical analysis was performed. In Phase II, except for the Ischemic group, left ventricular function was assessed on a modified Langendorff apparatus preceding metabolic analysis. RESULTS: Global normothermic ischemia (Ischemic group) resulted in reduction of glycogen levels, O2 consumption during state 3 and respiratory control rate (RCR) of mitochondrial respiration, and in elevation of lactate levels. Without reperfusion (Phase I), a significant biochemical improvement was noticed after infusion of 4 doses of hypothermic cardioplegia (Hypothermic group) except for the lactate levels that remained higher than the Control group. After normothermic cardioplegia (Normothermic group) biochemical variables showed values similar to the Control group. Reperfusion (Phase II) was followed by restoration of all biochemical variables to baseline (Control group). LV function showed similar results between Control, Normothermic and Hypothermic groups. CONCLUSIONS: The intermittent antegrade infusion of blood cardioplegia at 37° C and 17° C, infused at 20 minutes intervals, produced similar biochemical and functional results in rabbit hearts submitted to a prior period (20 minutes) of acute normothermic ischemia.

Proteína p53 em nefroblastomas

A imunoexpressao do antigeno p53 foi estudada em 35 pacientes com idade media de 38± 29 meses. Todos foram tratados com nefrectomia e quimioterapia, em 17 se associou tambem a radioterapia. O tempo medio de seguimento foi de 69± 66 meses. Em 5 deles a histologia era defavoravel. Em 10 casos (28,5%) a marcacao foi positiva, com ordem crescente de positividade para epitelio, blastema e estroma. Cinco pacientes faleceram da doenca, nenhum deles com histologia desfavoravel. Nao se encontrou relacao significante entre o padrao imunohistoquimico e os paremetros seguintes: sobrevida dos pacientes, estadio e grau do tumor.

Intraoperative Measurement of the Orifice Area in Patients with Mitral Valve Stenosis

This study was carried out in ten patients in order to compare results of mitral valve area evaluated by a new intraoperative technique and those provided by conventional hemodynamic methods. The results obtained correlated very well (r = 0.95) with values calculated by the Gorlin formula. Paired data checking were closer than 0.3 cm2 in all but one of patients with moderately severe mitral stenosis. It is concluded that the method for intraoperative measurement of the mitral valve area is simple, safe and reliable.

Is Left Ventricular Diastolic Thickening Documented During Dobutamine and Pacing Stress Echocardiography Related to Myocardial Ischemia? An Animal Model Study

Transient increase in diastolic wall thickness (pseudohypertrophy) during pacing stress echocardiography has been reported in normal myocardium. To evaluate the occurrence of pseudohypertrophy and to investigate the contribution of myocardial ischemia on its production during pacing and dobutamine stress echocardiography, we produced a physiologically significant coronary stenosis in 14 open chest dogs. The stenosis in the circumflex artery was measured by quantitative coronary angiography (range: 50% to 89% reduction in luminal diameter), and no resting segmental wallmotion abnormalities were observed by epicardial echocardiography (short‐axis, papillary level). In each study, dobutamine (5–40 μg/kg/min) and pacing (up to 260 beats/min) were performed randomly. Positivity of stress echocardiography tests was quantitatively determined by a significant (P < 0.05) reduction or failure to increase in absolute and percent systolic wall thickening in the myocardial area supplied by the stenotic artery as compared to the left anterior descending (LAD) artery‐related areas. Diastolic wall thickness and left ventricular diastolic area were compared before and after each stress test in the circumflex and LAD artery‐related regions. Pseudohypertrophy was observed in 57% and 86% of dogs for pacing and dobutamine, respectively, in the circumflex region, and in 50% and 64% in the LAD region. Despite its increased incidence in the circumflex region, the augmented diastolic wall thickness did not correlate with coronary stenosis severity or stress test positivity, but correlated inversely with changes in left ventricular diastolic area. In addition, it correlated directly with changes in heart rate only for pacing. In conclusion, pseudohypertrophy was a frequent finding during pacing and dobutamine stress echocardiography tests but was not related to myocardial ischemia in this animal model.

Antígeno MIB-1 em nefroblastomas

Foram estudados 35 pacientes tratados com nefrectomia radical e quimioterapia, em 17 (48,5%) dos quais se associou tambem a radioterapia. A idade media dos pacientes foi de 38± 29 meses e o tempo de seguimento pos-operatorio de 69± 66 meses. Obito pela neoplasia ocorreu em 5 pacientes, todos com histologia favoravel. As pecas conservadas em formol ou blocos de parafina para imunhistoquimica com anticorpo MIB-1, metodo da avidina-biotina-peroxidase. Em 13/35 (37,1%) dos tumores a marcacao para o MIB-1 foi positiva. As proporcoes respectivas de marcacao para blastema, epitelio e estroma foram: 34,6%, 18,7% e 0%. Nao houve diferenca estatistica entre a marcacao imunohistoquimica e com o tipo histologico, estadio e sobrevida dos pacientes.