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1.
Am J Clin Nutr ; 67(4): 669-84, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9537614

RESUMO

We report a comparison of natural and synthetic vitamin E in humans using deuterium labeling to permit the two forms of vitamin E to be measured independently in plasma and tissues of each subject. Differences in natural and synthetic vitamin E concentrations were measured directly under equal dosage conditions using an equimolar mixture of deuterated RRR-alpha-tocopheryl acetate and all-rac-alpha-tocopheryl acetate. Two groups of five adults took 30 mg of the mixture as a single dose and as eight consecutive daily doses, respectively. After a 1-mo interval the schedule was repeated but with a 10-fold higher dose (ie, 300 mg). In each case, the ratio of plasma d3-RRR-alpha-tocopherol to d6-all-rac-alpha-tocopherol (RRR:rac) increased from approximately 1.5-1.8 to approximately 2 after dosing ended. In an elective surgery study in which 22 patients were given 150 mg/d for up to 41 d before surgery, the RRR:rac in tissues was lower than in plasma and the percentage of deuterated alpha-tocopherol was lower in all tissues except gallbladder and liver. In a terminally ill patient given 30 mg/d for 361 d, plasma and tissue (x+/-SD) RRR-rac ratios (and % deuterated alpha-tocopherol) at autopsy were 2.06 (6.3%) and 1.71+/-0.24 (5.9+/-2.2%), respectively. In a second terminally ill patient given 300 mg/d for 615 d, the corresponding values were 2.11 (68%) and 2.01+/-0.17 (65+/-10%), respectively. The results indicated that natural vitamin E has roughly twice the availability of synthetic vitamin E. This 2:1 ratio is significantly higher than the currently accepted RRR:rac of 1.36:1.00. Gamma-Tocopherol, expressed as a fraction of total unlabeled tocopherols in 15 elective surgery patients, was 1.4-4.6 (mean: 2.6) times greater in adipose tissue, muscle, skin, and vein than in plasma, which is a substantially larger fraction than had been recognized previously.


Assuntos
Deutério , Vitamina E/análogos & derivados , Vitamina E/metabolismo , alfa-Tocoferol/análogos & derivados , Adulto , Procedimentos Cirúrgicos Eletivos , Humanos , Cinética , Pessoa de Meia-Idade , Especificidade de Órgãos , Estereoisomerismo , Doente Terminal , Tocoferóis , Vitamina E/administração & dosagem , Vitamina E/sangue , Vitamina E/farmacocinética
2.
Am J Surg ; 169(2): 202-6; discussion 206-7, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7840380

RESUMO

BACKGROUND: Because the abdominal insufflation and desufflation associated with laparoscopic procedures may adversely effect a compromised myocardium, patients with significant cardiopulmonary disease should be closely monitored during these procedures. The utility of intraoperative pulmonary artery catheter (PAC) and transesophageal echocardiography (TEE) monitoring was studied in 10 patients with moderate to severe cardiopulmonary disease to identify patients at greatest risk for cardiovascular complications during laparoscopic cholecystectomy. METHODS: Ten patients were enrolled in this prospective study; 7 had suffered a previous myocardial infarction, 6 had undergone coronary artery bypass grafting, and 9 had disease classified as Goldman's class II or greater. The heart was monitored by TEE throughout the laparoscopic cholecystectomy by using real-time, two-dimensional mode to study the wall thickness and motion. Several PAC measurements were taken directly: cardiac output, systemic vascular resistance, pulmonary artery wedge pressure, and central venous pressure. Heart rate and blood pressure were also obtained at corresponding intervals. Cardiac index, stroke volume, and left and right ventricular stroke work were then calculated. RESULTS: TEE demonstrated no significant changes in ventricular wall motion throughout laparoscopy. In patients who had postoperative cardiovascular complications, significant changes in cardiac index, left ventricular stroke work, and stroke volume were seen after pneumoperitoneum release. Compared to that of patients who did not develop complications, the cardiac index in those with complications dropped 42% (3.10 +/- 0.72 versus 1.80 +/- 0.10 L/min per m2, respectively; P < 0.01); left ventricular stroke work dropped 64% (139.00 +/- 11.36 versus 50.38 +/- 10.55 g x min/beat, respectively; P < 0.01); and stroke volume dropped 51% (86.90 +/- 12.68 versus 42.50 +/- 5.08 mL/beat, respectively; P < 0.01). CONCLUSIONS: PCA monitoring in patients with compromised cardiac function is useful in identifying patients who may not tolerate hemodynamic changes after pneumoperitoneum release. Normalization of hemodynamic changes secondary to abdominal insufflation and desufflation in patients with compromised hearts may not occur in patients with compromised hearts may not occur for hours postoperatively. Abnormal hemodynamic changes occur within the first hour after desufflation in patients who later develop cardiovascular complications, which are heralded by significant drops in left ventricular stroke work, cardiac index, and stroke volume. TEE did not prove to be useful for intraoperative monitoring.


Assuntos
Cateterismo de Swan-Ganz , Colecistectomia Laparoscópica , Ecocardiografia Transesofagiana , Cardiopatias/fisiopatologia , Hemodinâmica , Monitorização Intraoperatória , Idoso , Pressão Sanguínea , Débito Cardíaco , Cardiopatias/complicações , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Pressão Propulsora Pulmonar , Fatores de Risco , Volume Sistólico
3.
Ann Surg ; 217(5): 469-74; discussion 474-5, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8489309

RESUMO

OBJECTIVE: The incidence of acute pancreatitis in the elderly patient is increasing, and a significant number of such patients have no clearly defined etiology of their pancreatitis. To delineate the role of early organ failure versus progressive pancreatic disease in the morbidity and mortality, the authors' experience with patients older than 60 years with acute pancreatitis was reviewed. SUMMARY BACKGROUND DATA: As many as 30%-40% of elderly patients with acute pancreatitis have an unclear etiology and such patients have high rates of early organ failure and death. While some authorities have shown that pre-existing disease in these elderly patients did not contribute to subsequent morbidity, others have demonstrated that poor outcome was related to co-existing medical illness. METHODS: Their review of acute pancreatitis in the elderly was grouped into known and unknown etiology patients. Various parameters such as morbidity, mortality and length of stay were then compared between the two groups. Severity of organ failure and acute pancreatitis on admission were both graded and attempts made to correlate this severity with subsequent outcome. RESULTS: Unknown etiology patients had a greater number of Ranson's criteria (3.5 +/- .44 vs. 2.4 +/- .18) (p < 0.02), higher morbidity (48% vs. 22%) (p < 0.05), higher mortality (24% vs. 8.3%), and more SICU days (4.4 +/- 1.3 vs. 1.6 +/- .44) (p < 0.05) when compared with the known etiology group. Duration of symptoms, admission hypotension, and Ranson's criteria were unsuccessful in predicting mortality. Functional status of the various organ systems on admission did predict subsequent mortality. CONCLUSIONS: Elderly patients with acute pancreatitis of unknown etiology present with a more severe disease, have higher morbidity and longer SICU stays, and appear to have greater compromise of organ function. Organ function compromise correlates with mortality and appears more significant than severity of pancreatic disease. Aggressive support of such organ systems may be beneficial in the management of these patients.


Assuntos
Pancreatite/etiologia , Doença Aguda , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Insuficiência de Múltiplos Órgãos/etiologia , Pancreatite/complicações , Pancreatite/mortalidade , Prognóstico
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