PubMed Health⌕ Search

Biomedical subjects

P Angelos

Publications and source records attributed to P Angelos.

16 recordsLinked to original sources

Indications and results of liver resection and hepatic chemoembolization for metastatic gastrointestinal neuroendocrine tumors.

BACKGROUND: We reviewed 36 patients with liver metastases from islet cell tumors of the pancreas (n = 18) and carcinoid tumors (n = 18) who were treated with surgical resection (n = 16) or hepatic chemoembolization (n = 20). METHODS: All resections were complete and included 4 lobectomies, 6 segmental resections, and 6 wedge resections. There were no operative deaths. RESULTS: Median survival has not yet been reached, and the actuarial 5-year survival rate is 70%. Prognostic variables associated with improved disease-free survival included prior resection of the primary tumor and 4 or fewer metastases resected (P <.05). With an average of 3 chemoembolization procedures per patient, 17 of 20 patients (90%) demonstrated either a significant radiographic response (n = 5), stabilization of tumor mass (n = 2), or improvement of clinical symptoms (n = 10). Factors related to a sustained response (more then 1 year) included surgical resection of the primary tumor, 4 or more chemoembolization procedures, and liver metastases of 5 cm or smaller. Median survival after treatment was 32 months (range, 7-63 months), and the actuarial 5-year survival rate was 40%. CONCLUSIONS: Surgical resection of metastatic neuroendocrine tumors provides the best chance for extended survival. Chemoembolization effectively improves clinical symptoms and, in selected patients, may provide sustained tumor control.

Adenoma, Islet Cell↗

Evaluation of serum calcium levels in predicting hypoparathyroidism after total/near-total thyroidectomy or parathyroidectomy.

Hospital stays for thyroid and parathyroid surgery have decreased significantly with selected patients staying under 8 hours. Strategies to recognize hypocalcemia postoperatively vary. We examined timed postoperative calcium levels to determine how long one needs to monitor patients for hypoparathyroidism. We analyzed 120 consecutive patients having total/near-total thyroidectomy and/or parathyroidectomy between April 1998 and October 1999. Total and ionized serum calcium levels were obtained at 8, 16, and 22 hours postoperatively. Strict criteria for significant hypoparathyroidism were defined as a symptomatic patient, a total calcium value of less than 7.2 mg/dL, or an ionized calcium value of less than 1.0 mmol/L. Eighteen patients (15%) met criteria for hypocalcemia. The 8-hour ionized calcium level identified 40 per cent of those that needed supplementation. With the inclusion of the 16-hour ionized calcium value 94.5 per cent of patients who met criteria were identified. Of the 74 patients who had not previously received calcium at 22 hours after surgery only one patient with hypocalcemia was identified. Serial calcium values postoperatively add to the costs associated with an overnight hospital stay. In addition to clinical examination an ionized calcium level 16 hours postoperatively is sufficient to identify significant hypoparathyroidism in the majority of patients.

Adult↗

Palliative philosophy: the ethical underpinning.

This article explores the ethical underpinnings of palliative care and how contemporary surgical care reinforces much of the basis of palliative medicine. A common misconception is that palliative medicine has grown out of the rise of patient's rights; however, palliative care is grounded in the principle of beneficence that is central to traditional medical values. This article explores the notion of beneficence to understand how contemporary surgical care can be undertaken and how it is consistent with palliative care. Some of the difficulties with the dichotomy between curative and palliative care models in surgical practice are discussed. Finally, this article considers how the underlying philosophy of palliative care is consistent with the historical tradition of surgery and the contemporary goals of surgical care.

Ethics, Medical↗

An initial experience with radioguided parathyroid surgery.

BACKGROUND: Recent reports have shown the effectiveness of preoperative parathyroid scintiscanning as an aid to parathyroidectomy. Less attention has been paid to limitations of this approach based on patient characteristics. METHODS: All patients evaluated for primary hyperparathyroidism by an endocrine surgeon from December 1, 1998, through October 31, 1999, were retrospectively reviewed. Data were gathered to determine which patients were candidates for the radioguided approach, the effectiveness of this approach, and the reasons why some patients were not candidates for this approach. RESULTS: Thirty-three patients were evaluated. Based on history, 4 patients were not candidates for a radioguided approach. Of the remaining 29 patients, 19 had positive sestamibi scans (65.5%) and successful radioguided operations. The 10 patients (34.5%) with negative scans had successful standard parathyroidectomy. CONCLUSION: Although radioguided parathyroid surgery is an effective surgical approach, only 57.6% of patients in this series could have a radioguided operation. Standard four-gland exploration will continue to be needed for many patients.

Adenoma↗

Opinions and use of advance directives by physicians at a tertiary care hospital.

The physician-patient relationship is an essential part of end-of-life planning, including discussions of advance directives (AD). Physicians likely to encounter AD issues with their patients were identified and queried as to their knowledge, opinion, and experience with ADs. Though most physicians felt ADs were helpful to both physicians and patients, considerably less were familiar with hospital policies and the different types of ADs. Formal education in the use and function of ADs also appears to be lacking, suggesting a need to improve the way in which ADs are addressed during medical training.

Adult↗

Advance directive use among patients undergoing selected high-risk surgical procedures.

Since 1991, the Patient Self-Determination Act has required that all patients entering Medicare-reimbursed institutions be asked if they have an advance directive (AD) and be given information about advance directives if they do not have one. Patients undergoing elective high-risk surgery for diseases with a poor prognosis were identified as being most likely to benefit from an AD. The charts of patients being explored for possible pancreaticoduodenectomy or esophagectomy at a tertiary referral hospital in 1996 were retrospectively reviewed. Few patients had an AD, and there was little evidence that the presence of an AD affected patient care.

Advance Directives↗

Gangrenous cholecystitis: analysis of risk factors and experience with laparoscopic cholecystectomy.

BACKGROUND: Gangrenous cholecystitis occurs in up to 30% of patients admitted with acute cholecystitis. Factors predicting gangrenous disease in patients with acute cholecystitis remain poorly defined, making preoperative diagnosis difficult. Identification of these factors and early diagnosis of gangrenous cholecystitis will indicate more aggressive treatment, earlier operation, and a lower threshold for conversion of laparoscopic to open cholecystectomy. METHODS: We reviewed our experience with acute cholecystitis during the 2-year period of 1995 to 1996. Admitting history, physical examination, operative report, laboratory and radiology data, and pathology report were analyzed for each patient. Acute cholecystitis and its gangrenous complication were diagnosed by both gross and microscopic examination. RESULTS: One hundred fifty-four patients were admitted to the hospital with acute cholecystitis and underwent cholecystectomy; gallbladder gangrene was found in 27 (18%) of these patients. Four patients with gallbladder gangrene underwent open cholecystectomy and 23 patients underwent laparoscopic cholecystectomy, of which 15 (65%) were completed laparoscopically and 8 (35%) had open conversion as a result of severe inflammation. Risk factors for gallbladder gangrene included male gender, age older than 50 years, history of cardiovascular disease, and leukocytosis greater than 17,000 white blood cells/mL. CONCLUSIONS: Older male patients (age older than 50 years) with history of cardiovascular disease, leukocytosis greater than 17,000 white blood cells/mL, and acute cholecystitis have increased risk of gallbladder gangrene and conversion of laparoscopic cholecystectomy to open cholecystectomy. Urgent laparoscopic cholecystectomy with low threshold for conversion to open cholecystectomy should be considered in these patients at high risk for gallbladder gangrene.

Acute Disease↗

Medical ethics curriculum for surgical residents: results of a pilot project.

INTRODUCTION: This study sought to develop and evaluate a medical ethics curriculum designed specifically for surgical residents. METHODS: The learning needs of surgical residents relevant to ethics were determined by using a structured literature review and synthesis strategy. We identified 5 primary areas of importance for ethics education for surgical residents: withdrawing and withholding treatment, advance directives, do-not-resuscitate orders, informed consent, and communicating bad news. Learning objectives were developed, and teaching plans were designed for four 90-minute interactive teaching episodes on the basis of adult learning principles. We surveyed residents using a published survey instrument modified for surgery to identify residents' beliefs about the usefulness of ethics training, confidence in addressing ethical issues, and factual knowledge of ethics questions. RESULTS: Twenty surgical residents at a single institution completed the pretest and posttest close-ended surveys. Results showed that although 88% had formal ethics exposure in medical school, 93% considered ethics education at the resident level to be a "very important" or "important" topic. Residents' confidence in addressing ethical issues showed statistically significant improvement between pretest and posttest surveys for 13 of 23 items. There were no statistically significant linear relationships between postgraduate year of residency and the pretest confidence items or the number of correct responses on the pretest multiple-choice items. CONCLUSIONS: Despite the prevalence of ethics education during medical school, surgical residents welcome formal instruction on numerous ethical issues pertinent to surgical practice. A focused curriculum can be developed that has a measurable impact on residents' confidence in addressing ethical issues.

Adult↗

Bilateral adrenal cortical adenomas in primary hyperaldosteronism.

Bilateral adrenal cortical adenomas in the presence of primary hyperaldosteronism is an extremely rare condition. We present a case of primary hyperaldosteronism in which a unilateral hypersecreting aldosterone-producing adenoma coexisted with a large, contralateral adrenal mass ultimately found to be consistent with cortical adenoma. Management consisted of total adrenalectomy and enucleation of adenoma from the opposite adrenal. The patient is normotensive 3 years after surgery. Enucleation as a successful approach to hyperfunctioning cortical adenomas is proposed.

Adrenal Cortex Neoplasms↗

Riedel's thyroiditis: treatment with tamoxifen.

BACKGROUND: Riedel's thyroiditis is an often disabling disease with clinical and histologic similarity to several other fibrous inflammatory disorders. Surgical treatment alone is often unsatisfactory in permanently alleviating airway compression, dysphagia, neck immobility, pain, or chronic fatigue syndrome. Investigation of drugs shown to be of benefit in the treatment of related fibrous disorders in which hormonal factors or inflammatory deregulation appear to be important is indicated. Tamoxifen has not been previously used in the treatment of Riedel's thyroiditis. METHODS: Four patients with clinical and histologic diagnoses of Riedel's thyroiditis were evaluated before and after treatment with tamoxifen. Each had progressive symptomatic disease of 3 to 16 years' duration despite one or more surgical procedures and steroid therapy. Subjective improvement was noted in all cases, and objective changes were confirmed by periodic physical and computed tomographic examinations. RESULTS: Patients have been monitored for 1 to 4 years with subjective improvement in 100% and objective disease regression ranging from 50% to 100% in all patients. One patient had complete regression within 6 months, and another had more than 50% regression within 3 months. All have returned to predisease activity levels. There were no significant side effects of the therapy. CONCLUSIONS: Tamoxifen has proved to be the most effective drug therapy available for managing Riedel's thyroiditis. Our studies suggest that this is unrelated to antiestrogen activity. Tamoxifen's effectiveness may be caused by a mechanism by which it stimulates the release of transforming growth factor-beta, which may inhibit the fibroblastic proliferation characteristic of Riedel's thyroiditis.

Adult↗

Effects of mannitol on cultured corneal endothelial cell Na,K-ATPase activity.

Mannitol was introduced into the media of bovine corneal endothelial cells grown in culture. This was accomplished in order to compare its influence on Na,K-ATPase activity with that of high levels of glucose that inhibit the enzyme. The study was conducted with the intent of showing possible adverse osmolar effects on enzyme activity. Mannitol was found to inhibit NA,K-ATPase when compared with mannitol-free medium (11 U vs. 202 U). However, this inhibition was significantly greater than that produced by high levels of glucose. When mannitol was introduced directly into the assay for the plasma membrane-extracted enzyme, the inhibition was as severe (14 U) as for that placed in the culture medium. By way of comparison, glucose introduced into the enzyme assay caused no significant inhibition (189 U). The mannitol concentration used was 20 mM and in the media there was an osmotic pressure of 347 mOsmol/kg. The high glucose concentration was 25 mM and the osmotic pressure in the media was 341 mOsmol/kg. These osmotic pressures were compared with that of the control medium (with 5 mM glucose), which generated a pressure of 308 mOsmol/kg. None of these values were judged sufficiently high to rupture cell plasma membranes or alter cell morphology as seen by vital staining and phase contrast microscopy. In addition, it was found that mannitol had no effect on cellular DNA, whereas a previous study showed that high glucose caused an increased unwinding of duplex DNA. This study suggests that mannitol inhibits endothelial cell Na,K-ATPase by a different mechanism than that of glucose. It further points out that osmotic effects may not be involved with either mechanism.

Animals↗

Alteration of ATPase activity and duplex DNA in corneal cells grown in high glucose media.

An investigation was made on the possible effects of high levels (450 mg/dl) of glucose on the activities of Na,K-ATPase [E.C. (Enzyme Commission) 3.6.1.37] and Mg-ATPase (E.C. 3.6.1.4) in plasma membrane preparations of bovine corneal endothelial cells grown in tissue culture. The activities of these enzymes were compared with the activities of the same enzymes from cells grown in low or "fasting" levels (90 mg/dl) of glucose. All activities were assayed from cells that were secondary cultures (15-25 days after trypsinization). The results indicated a 76% decrease in activity for Na,K-ATPase (0.04 units in high glucose vs. 0.17 units in low glucose). The activity for Mg-ATPase also decreased by 33% (0.24 units in high glucose vs. 0.36 units in low glucose). A t-test for significance indicated that the loss of activity in both enzymes was highly significant (p < 0.001) in the high glucose media. Assays for ATPase activity of plasma membranes were also made directly in high glucose after removal of the membranes from cells grown in low-glucose media. However, those membrane ATPases showed no significant decrease in activity. Tests for DNA damage of cells grown in the presence of high levels of glucose indicated a 15.5% change (decrease) in the amount of double-stranded DNA remaining after alkali treatment. This change was highly significant also (p < 0.001). These data suggest that the diabetic state may negatively affect membrane-bound ATPases of the corneal endothelium and further point to the possibility of an altered synthetic rate of ATPase polypeptides as a result of DNA damage.

Animals↗