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A Salat

Publications and source records attributed to A Salat.

At least 19 recordsLinked to original sources
PubMed2001

Influence of hypotensive and normotensive anesthesia on platelet aggregability and hemostatic markers in orthognathic surgery.

This prospective randomized study investigated the influence of normotensive and hypotensive general anesthesia on platelet aggregability, intraoperative blood loss and parameters of plasmatic coagulation during extensive orthognathic surgery. A total of 30 patients were randomly allocated for either normotensive anesthesia maintained by continuous infusion of propofol and remifentanil (NORMO, n=10) or hypotensive anesthesia, whereby hypotension was induced by increasing the infusion rate of remifentanil (HYPO-R, n=10) or by administration of nitroglycerin (HYPO-N, n=10). Whole blood platelet aggregability was significantly reduced during hypotension compared to normotensive anesthesia (P<.01, HYPO-N and HYPO-R vs. NORMO). Mean arterial blood pressure during hypotension correlated well with adenosinediphosphate- (R=.712, P<.001) and collagen-induced platelet aggregability (R=.685, P<.001). Within hypotensive study groups, postoperative fibrinogen levels were significantly different, whereas intraoperative platelet aggregability, postoperative platelet count, prothrombin time, activated partial thromboplastin time and antithrombin levels were not different. Normotensive anesthesia, however, caused significant decreases in platelet count (-29%), prothrombin time (-24%), fibrinogen (-41%) and antithrombin (-28%) and a significant prolongation in activated partial thromboplastin time (+21%) and thrombin time (+18%). There was a trend to reduced intraoperative blood loss in hypotensive study groups; however, differences were not significant. In conclusion, induced hypotension--independent of substances used for induction of hypotension--reduces intraoperative platelet aggregability, subsequently protecting the coagulation system against subclinical consumption coagulopathy. Induced hypotension-caused platelet dysfunction does not lead to an increased intraoperative blood loss, but quite on the contrary shows a trend to reduced intraoperative blood loss, possibly by preventing platelet-induced subclinical consumption coagulopathy.

Adult↗
PubMed2000

Early detection of preeclampsia by determination of platelet aggregability.

Preeclampsia is still a leading cause of maternal and fetal morbidity and mortality. There is evidence for the involvement of platelets. Therefore, we investigated the suitability of corrected whole blood impedance aggregometry as an early predictor of preeclampsia in 71 consecutive, high-risk pregnancies. According to the occurrence of preeclampsia, defined postpartum by an independent investigator, and the stage of pregnancy (early and late, cutoff: 25 weeks of gestation), four study groups were defined. Platelet aggregation data were corrected for the influence of hematocrit and platelet count by a special purpose software package. Women developing preeclampsia showed significantly higher platelet aggregation response compared to controls in early and late pregnancy. In early pregnancy, all women developing preeclampsia had aggregation responses to collagen higher than the highest responses among the controls. Hence, this test had a 100% positive predictive value of subsequent preeclampsia. Despite being significantly increased, platelet aggregability was of minor predictive value in late pregnancy. We conclude that preeclampsia is accompanied by exaggerated platelet aggregability, particularly perceptible early in the course of pregnancy. We propose collagen-induced whole blood platelet aggregation with correction for the influence of hematocrit and platelet count for early detection of preeclampsia.

Adenosine Diphosphate↗
PubMed2000

[Complete resection of isolated lung metastasis from breast carcinoma results in a strong increase in survival].

BACKGROUND: Surgical treatment of pulmonary resection for metastatic disease has been proven a valuable therapeutic concept for a variety of neoplasms. Concerning breast cancer, at least 25% of patients develop distant metastases. In spite of increasingly sophisticated palliative therapies, the survival of these patients did not appear significantly prolonged during the last 25 years (19-32 months following diagnosis) and about 95% die from metastatic disease. METHODS: Between 1977 and 1997, three epidemiological comparable groups out of a total of 125 patients of our clinic were treated for isolated pulmonary metastasis following breast cancer. Complete data from 96 patients were retrospectively analyzed following stratification to three groups according their surgical therapy: C, complete resection, 28 patients; I, incomplete resection, 34 patients; N, no resection, 34 patients. RESULTS: Comparison of the three therapy methods concerning stage, histology and receptor levels of the primary tumor, number of metastases and the disease free interval (DFI), as well as adjuvant therapy modalities yielded no significant differences. Mean survival of group C was with 79 months (5-years-survival 80%, 10-years-survival 60%) significantly better compared to groups I and N (p < 0.00002). Mean survival of group I and N was not significantly different (15.5 and 9 months respectively). The DFI had no impact on the survival of group C, but showed a high correlation with the survival of group N (R2 = 0.81). CONCLUSIONS: Routine chest X-ray is necessary in the follow-up of breast cancer patients and if coin lesions occur, thoracic surgeon should be contacted.

Aged↗
PubMed1999

Changes of platelet surface antigens in patients suffering from abdominal septic shock.

Sepsis and related syndromes account for a high morbidity and mortality caused by the development of multiorgan failure. Pathogenesis of sepsis is complex, involving humoral as well as cellular factors. Since the role of platelets is still undefined in this concern, we investigated CD63, CD62P, CD36, and CD31 expression on platelets of patients in septic shock (n = 18) using a flow cytometric assay in whole blood. Samples were drawn within 24 hours of onset. We found thrombocytopenia accompanied by a significantly higher expression of CD63, CD62P, and CD31 and a significant downregulation of CD36 in comparison to healthy volunteers (n = 18). Changes in CD63 and CD62P expression indicates platelet activation. Because CD62P, CD36, and CD31 mediate interaction of platelets with leukocytes, subendothelial matrix and probably endothelial cells as well as platelet adhesion/aggregation, our findings suggest an involvement of platelets in leukocyte/endothelial cell interaction in septic shock. We suspect that thrombocytopenia is not due to bone marrow depression, but rather is due to consumption of highly activated platelets in the microcirculation. We feel that our observations may offer a rationale for potentially beneficial effects of antiplatelet therapy in sepsis; however, further studies have to evaluate its beneficial impact as well as its potential risk for bleeding complications.

Antigens, CD↗
PubMed1998

[Significant extension of survival by complete resection of isolated lung metastases after breast carcinoma].

At least 25% of breast cancer patients develop distant metastases. In spite of increasingly sophisticated palliative therapies, the survival time of patients with metastasis did not appear to be significantly prolonged during the last 25 years (19-32 months following diagnosis) and 95% of them die from metastatic disease. Therefore, it seems appropriate that the therapeutic risk/benefit ratio and impact on quality of life should be reassessed when asymptomatic patients are treated. Surgical treatment and pulmonary resection for metastatic disease has been proven a valuable therapeutic concept for a variety of malignancies. Three epidemiologically comparable collectives out of a total of 125 patients from our clinic were treated for isolated pulmonary metastasis following breast cancer (observation period: 1977-1997). Complete data sets could be established for 96 patients and were retrospectively analyzed following stratification into three groups according to their surgical therapy. Twenty-eight patients underwent complete resection (K), 34 had incomplete resections (I) and 34 had no surgical intervention for lung metastases (N). Comparison of the three therapy arms concerning stage, histology and receptor levels of the primary tumor, number of metastases, and the disease-free interval yielded no significant differences between groups K, I and N. Patients after complete resection of isolated lung metastases (group K) had a mean survival of 79 months (5-year survival 80%, 10-year survival 60%). This was significantly better than groups I and N (P < 0.00002). The mean survival of groups I and N was not significantly different (15.5 and 9 months respectively). The disease-free interval after operation of the primary tumor had no impact on the survival of group K, but showed a high correlation with the survival of group N (R2 = 0.81). Complete resection of isolated pulmonary metastases from carcinoma of the breast results in marked prolongation of survival with a low morbidity rate. Hence, routine chest X-ray should be considered an indispensable part of the oncological aftercare in breast cancer patients.

Adult↗
PubMed1997

Variable platelet response to low-dose ASA and the risk of limb deterioration in patients submitted to peripheral arterial angioplasty.

A group of 100 patients with intermittent claudication (70 male, 30 female), treated with I00 mg ASA per day, were followed over 18 months after elective percutaneous balloon angioplasty. Platelet function was monitored over a period of 12 months by corrected whole blood aggregometry (CWBA). Upon stimulation by arachidonic acid (AA), adenosine diphosphate (ADP) and collagen, CWBA-results were obtained by an electronic acquisition and evaluation system correcting for hematocrit and platelet count of the blood sample. All patients showed a completely inhibited platelet response to AA stimulation. Comparison of the CWBA-results with clinical parameters revealed that reocclusions at the site of angioplasty occurred exclusively in male patients for which CWBA failed to prove an inhibition of aggregation upon both agonists, ADP and collagen, and for these patients the risk of complication is at least 87% higher (p = 0.0093). Only 40% of male patients show the expected effect of ASA on in vitro platelet aggregation at any given point in time and CWBA is capable of predicting those male patients which are at an elevated risk of reocclusion following peripheral angioplasty.

Administration, Oral↗
PubMed1996

Influence of UW solution on in vitro platelet aggregability.

Bleeding problems in orthotopic liver transplantation (OLT), starting immediately after reperfusion of the graft, are complicating the outcome of transplantation. Platelets may be involved in this situation, but there is still a lack of information about the influence of UW solution on platelet function. We evaluated the effect of UW solution on in vitro platelet aggregability in healthy volunteers using whole blood electrical aggregometry and concluded, that UW solution causes impaired platelet aggregability and may contribute to bleeding problems during OLT. The mechanism of impairment remains unclear, since central pathways as well as membrane receptors seem to be involved. Furthermore, our data support the necessity of extended flushing of the liver graft after reperfusion.

Adenosine↗
PubMed1995

Influence of hematocrit and platelet count on impedance and reactivity of whole blood for electrical aggregometry.

Previous studies have shown that differing qualities of blood specimen seem to influence whole blood electrical aggregometry (WBEA), making it difficult to standardize the method. The aim of this study was to investigate the impact of hematocrit (HCT) and platelet count (PLC) on in vitro platelet aggregation in citrated whole blood (CWB) in order to compensate for their possible effects on impedance aggregometry. Red blood cells and blood platelets were isolated from fresh citrated whole blood taken from 15 healthy donors (mean age = 26 years) and recombined to 20 physiologically relevant combinations of hematocrit and platelet count (HCT: 20-50, PLC: 100-500). Platelet aggregability was measured using WBEA with three different triggers. A special-purpose software package was used in this study, ensuring proper calibration, acquisition, and evaluation of analogue to digital converted data, allowing the calculation of a set of characteristic parameters of each impedance curve. Most of the linear regressions showed that all parameters significantly depend on HCT and PLC. Furthermore, we found interactions of both variables, making it impossible to focus on the effects of one of the investigated variables only. The outcome of this study is a set of dependences, allowing the calculation of regressions for in vitro aggregation in whole blood, enabling a comparison of blood of any quality with each other, regardless of the variables HCT and PLC. Together with the previously defined dependence of sample age on WBEA data, this step should help to make this technique a more reliable and practicable clinical tool, making it suitable for daily routine investigations.

Adult↗
PubMed1995

[Diagnostic and therapeutic video thoracoscopy: conversion rate and costs].

With the further development of new surgical techniques, that allow for the performance of a variety of standard diagnostic and therapeutic procedures in a less invasive fashion, it is instructive to look at the complications of these new techniques, in order to define their role for general thoracic surgery. 372 patients have been treated by means of video-assisted thoracic surgery (VATS) between 1/1992 and 12/1994. A total of 934 open thoracic procedures were performed in the same time frame, 399 out of them for the same chest disorders as treated by VATS alternatively. In 40 cases (10.7%) the endoscopic procedure had to be converted to an open thoracotomy. The main reasons for conversion were inability to locate or resect lesions due to a deep or central position (n = 13), requirement of further resection (n = 10), adhesions (n = 9), fibrinopurulent empyema (n = 5), bleeding (n = 2) and single-lung-ventilation failure (n = 1). The mean operation time was significantly shorter with VATS compared to open procedures, except for decortications. The mean hospital stay was 4.2 days in the endoscopic and 7.9 days in the thoracotomy group. Cost analysis for both techniques included expenses for disposable instruments, the operation room, anesthesia, and total hospital charges. Higher costs for instruments for VATS procedures were compensated by shorter chest drainage, less postoperative need for analgetics and a significantly shorter hospital stay.(ABSTRACT TRUNCATED AT 250 WORDS)

Cost-Benefit Analysis↗
PubMed1994

[Vascular surgery and smoking--a retrospective multivariant analysis].

In a retrospective study of 2,988 patients operated because of chronic occlusive arterial disease preoperative smoking habits were related to the patency rates of arterial reconstructions of carotid arteries, infrarenal aorta, iliac vessels, of the lower extremity, and to overall survival rates: 1) 75.2% of the patients were smokers, 24.8% were nonsmokers (NS). 2) Smokers needed the first vascular procedure about 7 years earlier than NS (62.4 +/- 10.3 vs. 69.9 +/- 9.9 years of age; p = 0.001). 3) A significant difference between the 2 groups could be found regarding the location of occlusion (p = 0.000): 20.7% of all occlusions of infrarenal aorta and iliac vessels occurred in smokers (8.8% NS), whereas NS showed a higher percentage of carotid artery stenosis (20.5 vs. 11.9% in smokers). 4) Postoperative morbidity and mortality did not differ between the 2 groups. There was no difference regarding primary patency rates and preoperative smoking habits. 5) The late patency rates of reconstruction of the legs were 72.4 and 52.9% for smokers 1 and 5 years after operation, which was significantly higher than in NS (65.5 and 46%). 6) The overall number of reoperations was higher in smokers than in NS (p = 0.001). 7) Smokers received significantly less often a further anticoagulant treatment than NS (40 vs. 47%; p < or = 0.05). 8) Preoperative smoking habits influenced the overall survival rate in a statistically significant manner with disadvantage for smokers (74.5 vs. 79.9 years; p = 0.000).

Adult↗
PubMed1994

[Diabetes mellitus and vascular surgery: a retrospective, multivariate analysis].

The influence of diabetes mellitus on the outcome of arterial reconstructions was evaluated. 25.7% of 2,735 patients (average age: 63.7 years), who underwent arterial reconstruction for arterial occlusive disease, suffered from a diabetes mellitus in need of treatment. The sex ratio within the diabetic patients was 2:1 (male:female). Regardless other influencing factors insulin-depending diabetic patients (average age: 64.6 years) were operated in average 1 year earlier than non-diabetics (average age: 65.5 years). No significant differences were found for perioperative complications. Overall, diabetic patients live significantly shorter than non-diabetics (average age: 72.8 vs. 75.8 years). Concerning the survival after the operation a stronger influence can be seen (8.3 vs. 4.4 years). The lower extremity was found to be the main localization for this negative observation on survival of patients (femoro-popliteal: 8.3 vs. 3.5 years; femoro-crural: 7.7 vs. 3.8 years). No statistical significant differences between diabetics and non-diabetics were found concerning patency rates of a reconstruction of the carotid, the aortic or the iliac arteries. There was a slight tendency pointing to a worse patency in diabetics undergoing reconstruction of the femoro-popliteal level (diabetics: 77%/1, 63%/3, 38%/5 years; non-diabetics: 80%/1, 67%/3, 58%/5 years), but this tendency did not reach statistical significance. A similar result was seen in patients with femoro-crural reconstructions (diabetics: 67%/1, 51%/3, 43%/5 years; non-diabetics: 68%/1, 56%/3, 49%/5 years). We were forced to perform a major amputation significantly more often in diabetics than in non-diabetics (13% vs. 7% after 1 year).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

In vitro hematological testing of rotary blood pumps: remarks on standardization and data interpretation.

Pump test procedures using blood will have to meet several standards not only to obtain reliable results in vitro but also to allow comparison of results of different investigators. This article reviews some of the issues that should be considered in pump testing, especially referring to the discussions held at the International Workshops on Rotary Blood Pumps in 1988 and 1991. The test loop itself should meet some requirements such as constant physiological temperature, standardized circulating volume, control of pressure and flow, and exact definition of the blood-contacting surface. Specifications have to be made concerning the test fluid blood, including sampling technique, anticoagulation, blood gases, pH, and glucose level. Only fresh blood should be used. Heparin is recommended for anticoagulation because it will be used also in vivo. Different procedures for cleaning and rinsing of plastic materials for reuse are mentioned. Bacterial overgrowth, which can lead to extreme oxygen consumption and acidosis, may be avoided through addition of antibiotics (e.g., gentamicin). To be able to compare data of the different working groups, a new modified index of hemolysis (MIH) has been defined.

Animals↗
PubMed1990

The influence of sample age on collagen-induced platelet aggregation in whole blood.

Whole blood electrical aggregometry (WBEA) has become an accepted method to gain quick information on platelet disorders. Compared to the optical method WBEA is closer to physiology and less complicated, but on the other hand more difficult to standardize. Different approaches have been attempted in the past to improve the reliability and practicability of this technique. The influence of sample age has not been defined so far. In a first step a mathematical modelling program was established, which is able to characterize the aggregation curves obtained after collagen stimulation. In a mathematical analysis various characteristics of the curve function were calculated and their sensitivity for aging investigated. Regression was performed for each characteristic, and correction factors defined. Our results indicate, that whole blood specimen for collagen induced aggregation can be used without correction factor up to 30 minutes. Data obtained with an age exceeding half an hour have to be corrected following a quadratic regression.

Blood Preservation↗
PubMedDate not supplied

Bcl-2 protein expression correlates with nodal status in non small cell lung cancer.

We investigated the immunohistochemical expression of bcl-2 in 55 non small cell lung cancer patients in order to understand if the altered expression of this gene is involved in the development of this kind of neoplasm. Our results showed bcl-2 immunopositivity to be a frequent event in non small cell lung cancer (54.5%) with a higher expression in squamous carcinomas compared to adenocarcinomas (p = .04). In addition, we found a positive correlation between bcl-2 expression levels and nodal status (p < .003). We suggest that bcl-2 immunostaining could be considered as marker of loco-regional invasivity.

Adenocarcinoma↗