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1.
Brain Circ ; 9(1): 39-43, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37151796

RESUMEN

Dural arteriovenous fistulas (DAVFs) are direct communication between the dural arterial and venous systems. They are more common in adults. In children, they are relatively rare. Hydrocephalus is a common problem in pediatrics with a variety of causes. However, very few cases of hydrocephalus as a complication of DAVF have been reported in the literature. This case describes an 8-month-old male child with a large DAVF at the torcular herophili who presented with regression of milestones and hydrocephalus. Magnetic resonance imaging (MRI) on admission showed triventricular hydrocephalus and a massively dilated torcular with a compressed fourth ventricle. Angiography confirmed the presence of a DAVF at the torcula with arterial feeders from the posterior circulation. Endovascular embolization was performed with >80% embolization of the fistula with no complications. Control MRI immediately postoperative was acceptable. No cerebrospinal fluid (CSF) diversion was performed. At a 3-month follow-up, the child had attained all developmental milestones for age. MRI showed normal CSF dynamics and a further reduction in the size of the torcula. Despite being rare, DAVFs should be considered as a possible cause of pediatric hydrocephalus, and treating them can lead to a resolution of the mechanisms inducing hydrocephalus. CSF shunting should be reserved for those cases with persistent hydrocephalus and raised intracranial pressure despite endovascular treatment.

2.
Surg Neurol Int ; 14: 100, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37025530

RESUMEN

Background: Recurrent disc herniations remain a challenge in spinal surgery. Although some authors recommend a repeat discectomy, others offer more invasive secondary fusions. Here, we reviewed the literature (2017-2022) regarding the safety/efficacy of treating recurrent disc herniations with repeated discectomy alone. Methods: Our literature search of recurrent lumbar disc herniations included; Medline, PubMed, Google scholar, and the Cochrane database. We focused on the types of discectomy performed, perioperative morbidity, costs, length of surgery, pain scores, and incidence of secondary dural tears. Results: We identified 769 cases that included 126 microdiscectomies, and 643 endoscopic discectomies. Rates of disc recurrence ranged from 1% to 25% with accompanying secondary durotomy varying from 2% to 15%. In addition, operative times were relatively short, ranging from 29.2 min to 125 min, with a relatively small average estimated blood loss (i.e., minimal to maximally 150 mls). Conclusion: Repeated discectomy was the most commonly performed treatment for same-level recurrent disc herniations. Despite minimal intraoperative blood loss and short operating times, there was a significant risk of durotomy. Notably, patients must be informed that more extensive bone removal for treating recurrent disc increases the risk for instability warranting subsequent fusion.

3.
Gynecol Oncol ; 161(2): 347-352, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33678480

RESUMEN

OBJECTIVES: To assess associations between treatment and recurrence-free survival (RFS) among patients with isolated tumor cells (ITCs) in sentinel lymph nodes (SLN) and otherwise stage I/II endometrioid endometrial cancer (EC). METHODS: A multi-institutional retrospective study of patients with SLN ITCs (<200 cells and < 0.2 mm) was performed. Only patients with otherwise stage I/II EC, endometrioid histology, and no evidence of micro-or macrometastases were included. Univariate and multivariable Cox proportional hazard models were used to evaluate associations between treatment, tumor characteristics, and RFS. RESULTS: 175 patients were included. Median follow up time was 31 months. 39% stage IB and 12% stage II disease. 76 (43%) received no adjuvant therapy or vaginal brachytherapy only (NAT/VBT), 21 (12%) had external beam radiation (EBRT), and 78 (45%) received chemotherapy +/- radiation. Patients who received chemotherapy more often had tumors with deep myoinvasion, lymphovascular space invasion (LVSI), and higher grade. Nine (5.1%) patients recurred; 5 distant, 3 retroperitoneal, and 1 vaginal. Extra-vaginal recurrences were similar in patients with or without chemotherapy (5.2% vs 3.8%, p = 0.68). After controlling for stage, LVSI and grade, chemotherapy and EBRT were not associated with RFS (HR = 0.63, 95%CI 0.11-3.52, and HR = 0.90, 95%CI 0.22-3.61, respectively). Type of lymph node dissection and ITC detection method were not associated with RFS. CONCLUSIONS: Risk of retroperitoneal and/or distant recurrence is low (4.6%) for patients with stage I/II endometrioid EC and ITCs in SLNs regardless of treatment. Our preliminary data suggests that adjuvant therapy may not be significantly associated with RFS. However, longer follow-up time and a larger sample size are needed before definitive recommendations regarding adjuvant therapy for patients with EC and only ITCs in SLN can be made.


Asunto(s)
Carcinoma Endometrioide/patología , Carcinoma Endometrioide/terapia , Neoplasias Endometriales/patología , Neoplasias Endometriales/terapia , Ganglio Linfático Centinela/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Endometrioide/diagnóstico , Quimioradioterapia Adyuvante , Supervivencia sin Enfermedad , Neoplasias Endometriales/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Resultado del Tratamiento
5.
Hematol Oncol Clin North Am ; 8(6): 1045-52, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7860436

RESUMEN

This article discusses anemia, the evaluation of symptoms, and the compensatory mechanisms that are brought into play by chronic anemia. The oxygen dissociation curve is described as is the effect of 2,3-DPG on hemoglobin-oxygen binding. Human tolerance to anemia is discussed and the article concludes with proposed transfusion strategies in chronic anemia.


Asunto(s)
Anemia/terapia , Transfusión de Eritrocitos , 2,3-Difosfoglicerato , Anemia/sangre , Enfermedad Crónica , Ácidos Difosfoglicéricos/sangre , Humanos
7.
Immunohematology ; 8(3): 77-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-15946062

RESUMEN

A gravida 1, para O, 17-year-old black female was found on prenatal testing to be group O, Du+, the latter test showing many unagglutinated cells. Because of the mixed-field appearance, the patient was thought initially to have bad a fetal-maternal hemorrhage. Additional red cell typings were performed, but no other apparent mixed-field reactions were observed. The Kleihauer- Betke test and hemoglobin electrophoresis indicated that the mixed-field agglutination was not due to a fetal-maternal hemorrhage. Thus, the finding of a mixed-field D typing could he explained best by a weak D antigen.

8.
Transfusion ; 31(4): 318-23, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2020994

RESUMEN

The cost of delivering a unit of blood (whole blood or red cells) to a hospitalized patient was examined in 19 United States teaching hospitals. The average hospital acquisition cost was calculated by using the prices charged by regional blood centers for blood products. To this cost was added an estimate of costs incurred by hospitals for handling, testing, and administering blood. Across study sites, the average hospital cost per unit transfused was $155 and the average charge to the patient was $219. Acquisition cost, the price that hospitals pay for blood, was 37 percent of the total cost to the hospital; the other 63 percent of the hospital cost included costs for blood bank handling (13%), laboratory tests (43%), and blood administration (7%). Significant variations in blood transfusion cost were found within our sample. Most of the variability can be attributed to geographic location of the blood supply source, type of red cell product transfused, prices charged by blood transfusion services, and the frequency of laboratory tests. The results of this transfusion cost study may be helpful in determining the costs of health care delivery, especially when blood transfusions are indicated.


Asunto(s)
Transfusión Sanguínea/economía , Costos y Análisis de Costo , Atención a la Salud/economía , Hospitales de Enseñanza , Humanos , Laboratorios de Hospital/economía
9.
Anesth Analg ; 66(11): 1151-4, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3662060

RESUMEN

Ketanserin, a serotonin antagonist, was used to control blood pressure during cardiopulmonary bypass in 12 patients having cardiac surgery. The drug was administered as a 10 mg bolus followed by a continuous infusion of either 40, 80, or 120 mg/hr to maintain mean arterial blood pressure below 70 mm Hg. There were 16 hypertensive episodes of which 15 (93.7%) were successfully controlled with ketanserin. Mean arterial pressure decreased significantly from an average of 72 +/- 3 to 52 +/- 9 mm Hg after 1 min. The effect that ketanserin had on platelets was also evaluated. Neither adverse nor salutary effects were seen in the platelet count, though a significant inhibition of serotonin-induced platelet aggregation was observed. Ketanserin proved effective for controlling hypertension during cardiopulmonary bypass but, despite inhibition of serotonin-induced platelet aggregation, it did not prevent thrombocytopenia.


Asunto(s)
Puente Cardiopulmonar/efectos adversos , Hipertensión/prevención & control , Ketanserina/uso terapéutico , Trombocitopenia/prevención & control , Anciano , Presión Sanguínea/efectos de los fármacos , Femenino , Humanos , Ketanserina/farmacología , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos , Recuento de Plaquetas , Serotonina/efectos adversos , Resistencia Vascular/efectos de los fármacos
13.
N Engl J Med ; 316(9): 517-20, 1987 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-3807996

RESUMEN

To determine the extent to which autologous blood that has been donated in advance ("predeposited") is used in patients undergoing elective surgery and to assess whether predonation decreases the use of homologous blood and the demand on the blood supply, we studied 4996 patients undergoing elective surgery at 18 tertiary care hospitals. Cross-matched blood was ordered for 1287 patients (26 percent), and of these, 590 (46 percent) were considered eligible for predepositing blood. Only 5 percent (32) of the eligible patients actually predeposited blood, indicating that predonation is not widely used. Of those who predeposited, only 13 percent (4 of 32) subsequently received homologous blood, as compared with 36 percent (199 of 558) of those who did not predeposit (P less than 0.01). Among the 199 patients who did not predeposit but required transfusion, we estimate that predonation could have avoided homologous transfusion in as many as 68 percent. If all eligible patients had predeposited autologous blood, they could have supplied as much as 72 percent of their own transfused red cells. The blood for as much as 10 percent of all red-cell transfusions could have been predonated by and transfused into the patients undergoing elective surgery. Greater use of predonation would not only reduce the demand on the blood supply by decreasing the need for homologous transfusion, but would probably also reduce the risk of hepatitis and other transfusion-associated illnesses.


Asunto(s)
Bancos de Sangre , Transfusión de Sangre Autóloga/estadística & datos numéricos , Procedimientos Quirúrgicos Operativos , Donantes de Sangre , Transfusión Sanguínea/estadística & datos numéricos , Transfusión de Sangre Autóloga/métodos , Hospitales de Enseñanza , Humanos , Estados Unidos
15.
Am J Obstet Gynecol ; 151(4): 494-7, 1985 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-3156500

RESUMEN

Platelet activation was assessed in hospitalized third-trimester patients with preeclampsia (n = 11) or chronic hypertension with superimposed preeclampsia (n = 11) and in healthy outpatient pregnant controls (n = 10) by measuring plasma beta-thromboglobulin, platelet factor 4, the platelet aggregate ratio, and the amount of collagen required to produce half-maximal aggregation velocity (Kd). Only plasma beta-thromboglobulin levels differed significantly between patients with preeclampsia (50.1 +/- 37.9; p less than 0.05) or chronic hypertension with superimposed preeclampsia (47.6 +/- 16.3; p less than 0.01) and the control subjects (22.5 +/- 11.3). beta-Thromboglobulin values in patients with preeclampsia, but not chronic hypertension with superimposed preeclampsia, correlated directly with 24-hour urinary protein loss (r = 0.93, p less than 0.001) and serum creatinine levels (r = 0.62, p less than 0.05) and inversely with creatinine clearance (r = 0.60, p = 0.05). We conclude that (1) beta-thromboglobulin is elevated in patients with preeclampsia or chronic hypertension with superimposed preeclampsia, (2) the normal platelet aggregate ratio and the Kd indicate that the increase in beta-thromboglobulin is not due to an intrinsic change in platelet responsiveness, and (3) the elevation of beta-thromboglobulin in patients with either preeclampsia or chronic hypertension with superimposed preeclampsia appears to be secondary to platelet consumption in the microvasculature, although in patients with preeclampsia altered renal function may be contributory.


Asunto(s)
Plaquetas/fisiopatología , Preeclampsia/sangre , Adulto , Plaquetas/efectos de los fármacos , Colágeno/farmacología , Creatinina/sangre , Femenino , Humanos , Hipertensión/sangre , Hipertensión/complicaciones , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Agregación Plaquetaria/efectos de los fármacos , Factor Plaquetario 4/análisis , Preeclampsia/complicaciones , Embarazo , Tercer Trimestre del Embarazo , Proteinuria/sangre , Radioinmunoensayo , beta-Tromboglobulina/análisis
16.
Anesth Analg ; 64(1): 30-3, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3917623

RESUMEN

The effects of intravenous nitroglycerin (NTG) upon the bleeding time, platelet aggregation response, and plasma 6-keto-PGF1 alpha concentration were measured in 17 patients about to undergo coronary bypass grafting. NTG produced a dose-related prolongation of the bleeding time that correlated with the accompanying decrease in systolic blood pressure. Platelet aggregation was not affected and measurements of 6-keto-PGF1 alpha failed to reveal detectable levels (less than 10 pg/ml) either before or after NTG infusion. This suggests that the prolonged bleeding time associated with NTG infusion may be due to vasodilation and increased venous capacitance, rather than altered vascular-platelet interaction.


Asunto(s)
Tiempo de Sangría , Nitroglicerina/farmacología , Pruebas de Función Plaquetaria , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Epoprostenol/fisiología , Femenino , Humanos , Infusiones Parenterales , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos
17.
J Clin Invest ; 75(1): 168-74, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3880771

RESUMEN

To understand the pathophysiologic significance of abnormal serum prostacyclin (PGI2) binding activities in thrombotic thrombocytopenic purpura (TTP), we evaluated the PGI2 binding characteristics in three chronic TTP sera and 19 normal sera. PGI2 binding by serum was rapid and reversible. The binding activity in TTP sera (22.1 +/- SD, 4.4%) was significantly lower than that of normal sera (42.2 +/- 6.2%). Moreover, the antiaggregating activity and 6-keto-prostaglandin F1 alpha (6KPGF1 alpha) content in the gel filtrates representing the binding peak was proportionally lower in a TTP serum than normal serum. Although normal and TTP sera bound [14C]arachidonate with similar activity, and neither bound [3H]6KPGF1 alpha, there was a difference in prostaglandin E1 (PGE1) binding. Binding of [3H]PGE1 was subnormal in two TTP sera (W.J. and T.G.) and normal in the third (H.S.). Normal serum corrected the binding defects of TTP serum. Interestingly, the mixture of two TTP sera (W.J. and H.S.) mutually corrected their PGI2 binding defects. In addition, although in vivo plasma transfusions improved the PGI2 binding activity of W.J. and H.S., there existed a striking difference in the nature of their response. These observations indicate that there is at least two types of PGI2 binding defects in TTP. Our data indicate that TTP is associated with diminished serum binding of PGI2. This defect may reduce the availability of PGI2 to damaged vascular sites and decrease an important modulator of platelet thrombus formation at times of severe vascular insult.


Asunto(s)
Epoprostenol/sangre , Púrpura Trombocitopénica/sangre , 6-Cetoprostaglandina F1 alfa/sangre , Adulto , Sitios de Unión , Disponibilidad Biológica , Cromatografía en Gel , Relación Dosis-Respuesta a Droga , Epoprostenol/metabolismo , Femenino , Semivida , Humanos , Masculino , Unión Proteica , Albúmina Sérica/farmacología
18.
Kidney Int ; 25(4): 671-6, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6434788

RESUMEN

The production of malondialdehyde (MDA) and thromboxane B2 (TxB2) by platelets following an arachidonic acid (AA) challenge was greater in nephrotic platelet rich plasma (PRP) than in normal PRP. The uptake of 14C-AA, and its subsequent conversion to 14C-TxB2 following a thrombin stimulus, was also greater in nephrotic than normal PRP. Normal plasma diminished the MDA production by nephrotic platelets. The addition of albumin to nephrotic PRP, or, the intravenous infusion of albumin in quantities sufficient to correct hypoalbuminemia also diminished the excessive production of prostaglandin metabolites by nephrotic platelets. The platelet aggregate ratio (PAR), which measures circulating platelet aggregates, was abnormal during the acute phase of nephrotic syndrome but reverted to normal following remission. These data indicate that hypoalbuminemia is associated with increased AA metabolism by platelets and suggest that platelet "hyperactivity" may contribute to the proclivity toward thrombosis observed in nephrotic syndrome.


Asunto(s)
Ácidos Araquidónicos/sangre , Plaquetas/metabolismo , Síndrome Nefrótico/sangre , Albúminas/administración & dosificación , Albúminas/farmacología , Ácido Araquidónico , Humanos , Infusiones Parenterales , Malondialdehído/metabolismo , Agregación Plaquetaria , Tromboxano B2/biosíntesis , Tromboxano B2/sangre
19.
J Vasc Surg ; 1(2): 261-8, 1984 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6434751

RESUMEN

Twenty-four patients who received no antiplatelet medications and underwent femorotibial bypass grafting (nine vein, 12 polytetrafluoroethylene [PTFE], and three composite PTFE-vein) had serial measurements taken of their platelet function and coagulation. The concentration of collagen required to produce half-maximal platelet aggregation (Kd), the platelet aggregation ratio, antithrombin III, factor VIII-related antigen, and fibrinolytic activity (platelet-rich plasma) was measured preoperatively and 3 and 7 days after surgery. Before surgery eight patients exhibited an increase of platelet reactivity to collagen. Following femorotibial bypass grafting, the mean preoperative Kd of 0.52 +/- 0.37 microgram/ml fell to 0.34 +/- 0.35 microgram/ml on the third postoperative day (P less than 0.001) and returned to 0.41 +/- 0.72 microgram/ml on day 7. Factor VIII-related antigen increased from a mean preoperative value of 248 +/- 29% of normal activity to a mean of 360 +/- 96% on postoperative day 3 (p less than 0.01) and further increased to 428 +/- 78% on day 7 (p less than 0.01). Fourteen patients had antithrombin III measurements taken, and their levels also fell on the third postoperative day (110 +/- 5.7% to 71 +/- 6.5%; p less than 0.001). No significant changes in fibrinolytic activity were noted. Persistent platelet reactivity was found in seven patients beyond the seventh postoperative day. After administration of 325 mg of aspirin, the abnormal platelet reactivity ceased. Increased platelet reactivity to collagen, factor VIII-related antigen, and a decrease in the antithrombin III level are indicative of a hypercoagulable state in these patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Coagulación Sanguínea , Plaquetas/fisiología , Prótesis Vascular/efectos adversos , Vena Femoral/cirugía , Antígenos/análisis , Antitrombina III/análisis , Plaquetas/efectos de los fármacos , Colágeno/farmacología , Factor VIII/análisis , Factor VIII/inmunología , Fibrinólisis , Heparina/farmacología , Humanos , Masculino , Agregación Plaquetaria , Factor de von Willebrand
20.
Biochim Biophys Acta ; 693(1): 22-6, 1982 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-7150590

RESUMEN

Tyramine and dopamine are taken up by rat platelets through the serotonin uptake mechanism while phenethylamine is not taken up. This indicates that an aromatic hydroxyl group is a structural requirement for the uptake of phenethylamine derivatives by rat platelets. Although none of these phenethylamine derivatives induce platelet shape change, they inhibit serotonin-induced shape change and serotonin uptake with the same relative potency (tyramine greater than phenethylamine greater than or equal to dopamine). This suggests that the receptors controlling serotonin uptake and serotonin-induced shape change have a common structural component that binds phenethylamine derivatives. However, the fact that phenethylamine derivatives activate the serotonin uptake mechanism but do not induce platelet shape change suggests that serotonin uptake and serotonin-induced shape change are mediated by two distinct activation sites of serotonin receptors.


Asunto(s)
Plaquetas/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/sangre , Animales , Plaquetas/efectos de los fármacos , Plaquetas/ultraestructura , Cinética , Agregación Plaquetaria , Ratas , Serotonina/farmacología , Tiramina/sangre
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