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R Arbogast

Publications and source records attributed to R Arbogast.

At least 19 recordsLinked to original sources
PubMed2006

The art of surgery in the 21st century: based on natural sciences and new ethical dimensions.

BACKGROUND AND AIMS: In the future, new surgical techniques will only be introduced in clinical practice if evidence-based results--frequently the results of controlled clinical trials--are presented. Unlike any other medical discipline, surgeons provide their diagnostic and operative skills through the surgeons' hand and the use of technical equipment, which ranges from instruments and devices employed during operation to the use of surgical robots. RESULTS: Analysing the fundaments of surgery on the turn of the century, there is only a little doubt about the increasing impact of data deriving from natural sciences on knowledge in medicine and management of diseases. The natural scientific method of detecting, measuring, and verifying facts is the methodological basis of surgery as well. The autonomy of the surgeon's clinical decision making is significantly restricted by the definition of guidelines. They shift the decision from a single patient to a collective panel. Patient safety and the efficiency of new treatment modalities compared with previous standards are the criteria for the judgement of innovative surgery today. The communication and interaction between surgeon-scientist and patients is guaranteed legally by written consensus. But beside of the high probability of benefit from therapy and written consensus, the surgeon-patient relation is determined by these factors: limitation of time for care of an individual patient, increase of time for administration and documentation, increase of bureaucratic barriers for medical research, and health cost constraints. CONCLUSION: The medical mandate to cure a sick patient is an individual mandate to take action. Measures, numbers, and images are only preconditions for a surgeon's action in daily clinical work; they can never replace it. The call for an ethical imperative in scientific surgery that is dependent on technology is justified when the state of science and uncritical use of surgical skills and financial constraints have major impact on providing medical care.

Decision Making↗
PubMed2003

Hepatic disseminated tumor cells in colorectal cancer UICC stage 4 patients: prognostic implications.

Approximately 30-50% of all colorectal cancer patients with a resectable primary tumor will subsequently develop metastatic disease due to tumor cell dissemination. In the case of limited solid hepatic metastasis, resection of the primary tumor and the respective hepatic metastasis can be curative. Our aim was to evaluate the incidence of hepatic DTC in patients with solid liver metastasis and to describe their prognostic impact. Therefore, we applied a sensitive PCR-RFLP assay detecting one K-ras mutant among one million wild-type cells. Tumor tissue and liver biopsies from 32 colorectal cancer patients staged UICC 4 undergoing palliative surgery could be obtained intra-operatively and were thereupon screened for the presence of hepatic DTC. The primary tumor of 16 patients (50%) harbored a K-ras mutation and survival of K-ras positive patients was reduced as compared to K-ras negatives (P=0.039). In 8 of the patients (50%) with a K-ras mutated primary, no hepatic DTC were detected, whereas the liver of the remaining 8 patients (50%), showed a coincidence of solid liver metastasis and hepatic DTC. Median survival of patients with solid liver metastasis and hepatic DTC was decreased as compared with patients without any hepatic DTC burden (median survival 165 vs. 240 days; log-rank P=0.951). A subgroup analysis revealed that survival was significantly decreased in the case of bilobal DTC affection as compared with monolobal hepatic DTC affection (median survival 68 vs. 355 days; log-rank P=0.002). We conclude that the detection of hepatic DTC is a powerful prognostic factor. Furthermore, bilobal hepatic DTC involvement might be a contraindication for the resection of solid liver metastasis.

Aged↗
PubMed2000

Increased therapeutic failure for cephalexin versus comparator antibiotics in the treatment of uncomplicated outpatient cellulitis.

We reviewed records of outpatients to determine the therapeutic failure rate of cephalexin in treating uncomplicated cellulitis. Therapeutic failure was defined as an increase in antibiotic dosage, prescription renewal, or addition or substitution of another antibiotic. Demographics, physical characteristics, risk factors, intervention, and outcome data were collected. Twenty-seven percent of patients failed therapy with an oral antibiotic. The failure rate for cephalexin was 40% versus 20% for comparator antibiotics (p=0.02, odds ratio [OR] 2.62, 95% confidence interval [CI] 1.18-5.75). We identified no statistically significant variables related to cephalexin failure. Concomitant acid suppressive therapy was administered with cephalexin in 42% of failures and 20% of nonfailures (p=0.11, OR 2.78, 95% CI 0.77-9.87). These data suggest that cephalexin's efficacy was less than that of other antimicrobials in treating cellulitis, possibly related to concurrent acid suppression.

Anti-Bacterial Agents↗
PubMed1996

Single-blind study of the effects of intravenous dolasetron mesylate versus ondansetron on electrocardiographic parameters in normal volunteers.

A single-blind, randomized, five-way cross-over, safety and tolerability trial was conducted to determine whether intravenous (i.v.) dolasetron mesylate at varying single doses induces changes in ECG intervals in healthy volunteers and to compare these changes with a single intravenous dose of ondansetron or placebo. Thirty healthy male volunteers received 1.2, 1.8, and 2.4 mg/kg i.v. dolasetron mesylate, 32 mg i.v. ondansetron, and placebo on 5 separate days. ECGs were recorded at intervals during the 24 h after study drug administration. The changes in ECG intervals observed after dolasetron mesylate or ondansetron were acute, transient, and asymptomatic. Dolasetron mesylate resulted in slight but statistically significant dose-related increases in heart rate (HR) and PR and QRS intervals (between h 0 and 4). A statistically significant increase in QTc interval was detected with both dolasetron mesylate (2.4 mg/kg) and ondansetron. Ondansetron also produced a slight but statistically significant increase in JT interval and a decrease in HR. These changes in ECG intervals were usually observed between h 0 and 4; all parameters returned to baseline within 8 h of treatment. The results demonstrate that both dolasetron mesylate and ondansetron prolong the QTc interval. However, dolasetron mesylate predominantly altered ECG parameters indicative of ventricular depolarization (QRS duration), whereas ondansetron predominantly affected ventricular repolarization as measured by a prolongation in the JT interval. Both dolasetron and ondansetron were well tolerated. The adverse event (AE) rate was 13.3% (4 of 30); all AE were of mild or moderate severity and were distributed across all dose arms.

Adult↗
PubMed1994

Variation in von Willebrand's Factor according to the treatment of acute myocardial infarction: physiopathological and clinical implications.

To investigate whether von Willebrand's Factor (vWF) changes as a result of the reperfusion strategy during acute myocardial infarction (AMI), vWF was measured on days 0, 1, 2, 3, 4, 5 and 15 in 34 patients with AMI. Thrombolysis was initiated in 22 patients and followed by a coronary angiogram 90 min later. In 13 patients the infarct-related artery was then patent (THR group). In nine patients the infarct-related artery was occluded and rescue percutaneous transluminal coronary angioplasty was performed (group THR+rPTCA). In 12 patients, primary PTCA was carried out (pPTCA group). Admission values of vWF were similarly high in the three groups, while changes in vWF over the following days were statistically different among the groups. No significant change was observed in THR, whereas a significant and prolonged increase was found after failed thrombolysis with PTCA (peak increase at day 5:1.54 +/- 0.04 U.ml-1). In the pPTCA group, a significant increase could only be found on day 3 (0.96 +/- 0.04 U.ml-1). Absence of a statistical rise in vWF might be a late indicator of successful thrombolysis. The prolonged increase in vWF after failed thrombolysis needing rescue PTCA probably reflects a higher resistance to thrombolysis, while the slight but significant increase in vWF following primary PTCA could be due to vascular injury.

Angioplasty, Balloon, Coronary↗
PubMed1994

Effect of cold pressor test on single-breath DLCO in normal subjects.

We hypothesized that the decrease in single-breath diffusing capacity of CO (DLCO) as observed in patients with Raynaud's phenomenon (P.J. Fahey et al. Am. J. Med. 76:263-269, 1984) may be present in normal subjects. Therefore, we examined 31 healthy subjects in two different laboratories. Two series of experiments were performed. In the first series DLCO was measured in 22 volunteers before (twice) and 5, 10, and 30 min after a cold pressor test (CPT), which consisted of immersing both hands in a 12 degrees C water bath for 2 min. In the second series right heart catheterization was performed in nine healthy seated subjects. Cardiac output, mean pulmonary arterial pressure, heart rate, and pulmonary wedge pressure were measured before, during, and 10, 20, and 30 min after the CPT. In every volunteer the CPT induced a decrease in DLCO that was still present 30 min after the test. In the nine catheterized subjects DLCO increased above control values during the CPT and then decreased below control values for 30 min. The CPT had no effect on cardiac output, heart rate, or pulmonary wedge pressure. In contrast, pulmonary arterial pressure and pulmonary vascular resistance increased during the CPT and then became lower than the control values for at least 30 min. In summary, the CPT induced a biphasic evolution of DLCO in normal subjects, being increased during the CPT and decreased after it. Our data are best explained by the West model of the lung. Our data suggest that the pulmonary Raynaud's phenomenon is not specific to patients with primary Raynaud's phenomenon.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Von Willebrand factor in coronary disease].

The value of studying factors of haemostasis and thrombosis in patients with coronary artery disease is established. The endothelial lesion and evolution of the thrombus play key roles in acute coronary syndromes and coronary angioplasty. The von Willebrand factor (VWF) is known for its participation in primary haemostasis. Deficits of this factor lead to a haemorrhagic syndrome, von Willebrand's disease. This glycoprotein is mainly synthesised by the endothelial cells. Its polymeric composition allows identification of two types of multimeres. The high molecular weight, active multimeres are liberated from the endothelium after stimulation by thrombin. Low molecular weight multimeres are less active and are secreted continuously. The VWF promotes platelet adhesion and facilitates platelet aggregation. Experimental pig models with VWF deficiency show that this factor is essential for the constitution of an occlusive thrombus. Several physiopathological mechanisms interact to increase VWF concentrations during thrombosis: the endothelial lesion, adrenergic stimulation, acute phase reaction. Increased VWF concentrations have been reported in many clinical situations. The results are most demonstrative in coronary artery disease. The VWF is abnormally high from the time of hospital admission in patients with acute myocardial infarction and continues to increase up to the 5th day before falling, without returning to normal values, at the 15th day. It is a sensitive though not specific late diagnostic marker of myocardial infarction. Increased VWF concentrations are not proportional to the severity of coronary atherosclerosis. They are, however, related to the infarct size, to the inflammatory reaction and to the prothrombotic phase.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1993

[Effects of phosphodiesterase inhibitors on diastolic function].

It has been clearly established that ischemic heart disease, hypertension and ageing affect diastolic function before any change is observed in contractile function. Though an increasingly recognised clinical entity, cardiac failure with normal systolic function still does not have any specific treatment. Phosphodiesterase inhibitors which increase AMPc, in addition to their inotropic and vasodilator effects, accelerate relaxation. Major and isolated abnormalities of relaxation have been demonstrated in vitro in non necrosed tissues of both the dilated and hypertrophic forms of advanced cardiomyopathy. The myocardium seems unable to restore rapidly the low cytosolic calcium concentrations required for the deactivation of the contractile proteins. The underlying mechanisms are probably very complex but a deficit in AMPc production has been demonstrated in very advanced stages of cardiomyopathy. In ischemia, however, the abnormalities of relaxation seem to be directly related to a defect in free energy production inhibiting the sarcoplasmic reticulum calcium pump. If abnormalities of relaxation due to ischemia and those due essentially to a passive mechanism are excluded, phosphodiesterase inhibitors would seem to have pharmacological effects likely to improve diastolic function. Clinical studies confirm the beneficial effects of Milrinone and Enoximone on relaxation and the rapid phase of diastolic filling, both in acute and chronic studies. However, it has not yet been clearly established whether improved diastolic function is due to a direct action on the myocardium or an indirect action due to improved conditions of load. In order to determine the specific effects of phosphodiesterase inhibitors on diastolic function, further research is required.(ABSTRACT TRUNCATED AT 250 WORDS)

Diastole↗
PubMed1993

[Acute myocardial infarction in patients over 70 years of age treated by immediate primary angioplasty].

Twenty consecutive patients aged over 70, admitted for acute myocardial infarction, underwent coronary arteriography within less than 6 hours after the onset of pain to confirm the diagnosis and determine the indications for other than thrombolytic reperfusion treatment, the risk of thrombolysis seeming theoretically prohibitive. In all cases, the artery responsible was found to be obstructed and, based upon this criterion, primary reperfusion angioplasty was performed. The criterion for success of angioplasty was the reappearance of distal flow (grade > 1 of the TIMI classification--Thrombolysis in Myocardial Infarction). The reperfusion rate obtained by angioplasty was 85%. Follow-up coronary arteriography during hospitalisation (between D10 and D15) in 17 patients revealed neither restenosis nor re-occlusion. In case of successful reperfusion, left ventricular ejection fraction improved by 16% (in absolute values). Hospital mortality was 15% (6 patients were in cardiogenic shock from the time of admission). Mortality (after a follow-up of 27.3 +/- 17.5 months) was 20%. Complications of the procedure during the acute phase included one femoral hematoma and one moderate coronary dissection, with an uncomplicated outcome. Angioplasty is an effective reperfusion method in patients aged over 70, and is an alternative to thrombolysis which, in this age group, is accompanied by a risk of hemorrhagic complications, cerebral in particular. Thus angioplasty can be suggested as first line treatment in elderly patients provided they have been admitted to a unit where operational cardiology is available on a continuous basis.

Aged↗
PubMed1992

Increase in radionuclide left ventricular ejection fraction after cardioversion of chronic atrial fibrillation in idiopathic dilated cardiomyopathy.

To assess the potential improvement in left ventricular ejection fraction after cardioversion of chronic atrial fibrillation to sinus rhythm in idiopathic dilated cardiomyopathy, we studied prospectively 17 patients, aged 58 +/- 6 years, by radionuclide angiocardiography at rest. Left ventricular ejection fraction was determined before treatment and at a mean delay of 4.7 months after cardioversion. Return to sinus rhythm was obtained in 12 patients, pharmacologically or by electrical cardioversion. Five patients remained in atrial fibrillation. No clinical, echocardiographic or haemodynamic finding could predict the success of cardioversion. In chronic atrial fibrillation, the ejection fraction did not change significantly: 30.0 +/- 9.1% (19 to 44%) at the first evaluation and 29.5 +/- 8.3% (22 to 41%) after 4.7 months. After successful cardioversion, left ventricular ejection fraction improved from 32.1 +/- 5.3% (24 to 41%) to 52.9 +/- 9.7% (37 to 71%) (P less than 0.001). The difference was 20.8 +/- 11.3% and left ventricular ejection fraction was normalized in 50% (6/12) of the patients. There was a significant reduction in the cardiothoracic ratio on chest X-rays and of the left ventricular end-diastolic diameter on echocardiography; fractional shortening increased (27.7 +/- 4.3% vs 20.3 +/- 2.7%, P less than 0.01). A third evaluation was realized after a mean delay of 11.7 months in the patients with successful cardioversion. Sinus rhythm was present in 83% (10/12) of the patients: seven patients were reevaluated by radionuclide angiography. The improvement in left ventricular function observed at the 4.7 months evaluation was still present. In two patients with recurrence of atrial fibrillation, there was a severe deterioration of left ventricular systolic function.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

[Acute myocardial infarction: immediate coronary angioplasty for failure or contra-indications of thrombolytic therapy. Apropos of a series of 100 cases].

One hundred patients admitted to a centre of interventional cardiology with acute myocardial infarction of less than 6 hours, underwent coronary angioplasty of first intention because of contra-indications to thrombolytic therapy (n = 20) or after thrombolytic therapy with streptokinase (n = 54), acylenzymes (n = 12) or tissue type plasminogen activator (n = 14). The indication of angioplasty were those of the TIMI (Thrombolysis in Myocardial Infarction) classification (occluded artery, TIMI grade 0) (n = 60) (suboccluded artery, TIMI grade 1) (n = 40). The criterion of success of angioplasty was an increase greater than 1 of TIMI grade. Reperfusion of the coronary artery was obtained by angioplasty in 95% of failures of thrombolysis and in 90% of patients with contra-indications to thrombolytic therapy. The early reocclusion rate at D1 was 2%. Repeat angioplasty at D1 was successful in both these cases and the arteries were still patent at D21. The reocclusion rate at the third week in 75 patients who underwent control coronary angiography was 5.3%. In patients with arterial occlusion, immediate angioplasty attained two objectives in the same procedure: a high rate of emergency myocardial reperfusion and a low rate of reocclusion. The average left ventricular ejection fraction (all arteries) significantly improved (+9.2% in absolute values) when the artery remained patent (p less than 0.001), especially when the initial ejection fraction was low. In the patients who had occluded arteries at control angiography at 3 weeks, the ejection fraction decreased (-4% in absolute values) (NS). The following complications were observed: 4 coronary artery dissections and haematomas at the site of femoral puncture in patients who had received thrombolytic therapy (10 drained surgically). The hospital mortality was 3% and global mortality after an average follow-up period of 19.6 months was 5%. Coronary angioplasty in acute myocardial infarction carries a low risk and seems to be beneficial in patients with contra-indications to or failure of thrombolysis.

Adult↗
PubMed1990

[Left ventricular filling in treated essential hypertension. A study using Doppler echocardiography].

The first stigmata of left ventricular involvement in hypertension are changes in diastolic filling. Early detection of these abnormalities is important as some antihypertensive agents may have beneficial effects on left ventricular distensibility and filling, in addition to lowering the blood pressure. This study compares parameters of left ventricular filling recorded by pulsed Doppler echocardiography in 44 treated hypertensives (average blood pressure: 157 +/- 20/93 +/- 12 mmHg) without any other coronary risk factors with 33 age-matched (52 +/- 13 years and 48 +/- 13 years) control normotensive subjects (average blood pressure: 130 +/- 11/80 +/- 7 mmHg). The main findings were an increase of the peak. A wave velocity after atrial contraction and of the A/E ratio in the hypertensive group (66 +/- 16 cm/s vs 53 +/- 14 cm/s, p less than 0.05 and 0.99 +/- 0.34 vs 0.78 +/- 0.24, p less than 0.05, respectively). These changes were more pronounced in patients with left ventricular hypertrophy. The rapid filling phase was unchanged (maximum E wave velocity = 68 +/- 18 cm/s vs 70 +/- 14 cm/s). The influence of age on peak A wave velocity and A/E ratio was obvious in control subjects and hypertensives without left ventricular hypertrophy r = 0.80; p less than 0.05). The age factor was not significant in the presence of left ventricular hypertrophy (r = 0.18). A weak linear correlation was observed between the peak A wave velocity, diastolic septal thickness (r = 0.44; p = 0.04) and left ventricular mass (r = 0.44; p = 0.05) in hypertensive patients with left ventricular hypertrophy.

Adult↗
PubMed1990

Alterations in left ventricular diastolic function in chronic ischemic heart failure. Assessment by radionuclide angiography.

Using radionuclide angiography at rest, we studied several parameters of left ventricular systolic and diastolic function in 60 patients divided into three groups, a control group (G1) of 15 patients and two groups of patients with chronic ischemic heart disease and previous anterior wall myocardial infarction but without aneurysm or dyskinetic wall motion, a second group (G2) of 23 patients with no history of heart failure, and a third group (G3) of 22 patients in New York Heart Association (NYHA) class II or III of heart failure. Ejection fraction, peak emptying, and peak filling rates, in addition to times to reach peak rates, were evaluated after constructing a global time-activity curve and its first time derivative. In addition, we computed the first time-derivative curves for each image pixel and obtained functional images (MIN/MAX images) representing the distribution of times to peak emptying or filling rates Using a left ventricular region of interest, time histograms were generated, and indexes of dispersion of times to peak rates, defined as the full width at half maximum of the histograms, were obtained. Significant (p less than or equal to 0.01) differences were observed among all groups for ejection fraction, peak emptying rate, and peak filling rate. The decrease of the peak filling rate still remained significant from group G1 to group G3 even after adjustment for differences in ejection fraction and heart rate. Peak filling rate was linearly correlated with ejection fraction in the population with ischemic heart disease (G2 + G3) (r = 0.68, p less than or equal to 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Coronary Disease↗
PubMed1989

[Isolated ST-segment depression in precordial leads V2 to V4. An early electrocardiographic sign of posterolateral myocardial infarction].

The authors report the cases of two men, 62 and 66 years-old, who both presented a posterolateral myocardial infarction which, in the first two days, as only electrocardiographic sign, consisted in a baseline offset of the ST segment in precordial leads V2 to V4. Necrosis and its topography were confirmed in each case by elevated myocardial enzymes, the progression of the electrocardiogram and bidimensional ultrasound cardiography exploration. Coronary angiography performed in both cases, revealed, in the first case, an isolated narrow stenosis of a first marginal artery, and in the second case, significant stenoses of the circumflex and right coronary artery without lesion of the anterior interventricular artery. These cases, along with those recently published in the literature, suggest that such alterations of ventricular repolarization which represent the reciprocal projection of a high posterior sub-epicardiac lesion current, could complete the electrocardiographic criteria of really thrombolysis in a context of prolonged precordial pain.

Arrhythmias, Cardiac↗
PubMed1989

Prevalence and predictors of smokeless tobacco use: Iowa's program against smoking.

Data from surveys of adolescents were analyzed so that we could determine the prevalence of smokeless tobacco use and identify and compare the concurrent correlates of its use and cigarette smoking. Panel data from seventh through eleventh and eighth through twelfth graders between 1980 and 1984 and cross-sectional data from seventh graders in 1980 and 1985 suggest that boys are more likely to use SLT than are girls and that the boys' use has increased with age and over time. Concurrent correlates of seventh-grade boys' and girls' SLT use and cigarette smoking were identified with discriminant analyses. Predictors of smokeless tobacco use were compared with those of weekly smoking for boys and girls separately. Predictors of use by boys were also compared with those by girls. Trying alcohol and the other form of tobacco were the only predictors that related to the use of either form by boys and girls. Differences among other predictors were noted and their implications for prevention are discussed.

Adolescent↗
PubMed1988

[Modifications in the contraction and relaxation of the left ventricle in chronic ischemic cardiopathies. Study using equilibrium angio-scintigraphy].

Our purpose was to confirm that abnormalities of left ventricular filling, which are associated with abnormalities of contraction, play an important part in the genesis of cardiac failure in chronic ischaemic heart disease. We used equilibrium radionuclide angiography of the cardiac cavities to study the behaviour of the left ventricle during contraction and relaxation in three groups of patients: a control group of 15 patients without cardiac disease (G2), and a group of 28 patients with chronic ischaemic heart disease complicated by cardiac failure (G3). From the overall activity-time curves and their first derivatives were calculated the ejection fraction, the peak ejection rate and the peak filling rate, as well as the time in the cardiac cycle when these appeared, the reference point in time being the end-diastole. Separately, an analysis of spatial distribution, pixel by pixel, of the elementary values of these times was developed with the help of new functional images constructed, pixel by pixel, from the first derivatives of the activity-time curves. These functional images were exploited by calculating histograms of times, and the width of the bars at mid-height was taken as the dispersion parameter expressed as a percentage of the cardiac cycle. There was a significant reduction of ejection fraction in groups G2 (49.8 +/- 11.6 p. 100) and G3 (36.3 +/- 15.4 p. 100) as compared to control group G1 (60.3 +/- 8.4 p. 100) (G1-G2 p less than 0.05; G2-G3 p less than 0.001; G1-G3 p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗