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S Horsch

Publications and source records attributed to S Horsch.

At least 19 recordsLinked to original sources
PubMed2005

[Standard procedures in hemodialysis shunt surgery].

Native arteriovenous (AV) fistula are the first choice for primary hemodialysis access. It is essential to save as much vein as possible, and therefore distal AV shunts should be tried first. In patients with diabetes, primary brachiocephalic shunts are indicated and show better results than distal AV fistulae. The major complication of AV fistulae is shunt thrombosis. Immediate surgical repair is necessary, with the aim of preserving enough puncture sites to allow prompt continuation of the hemodialysis therapy. It is important to avoid central venous catheters, because these cause infectious complications more frequently. Shunt infections occur more often in polytetrafluoroethylene grafts than in native AV fistulae and represent a life-threatening situation for dialysis patients.

Arteriovenous Shunt, Surgical↗
PubMed2004

Effect of doxapram on cerebral blood flow velocity in preterm infants.

BACKGROUND: Doxapram is used to treat apnea of prematurity when there is an insufficient response to methylxanthine treatment. As an unwanted side effect, reduced cerebral perfusion has been seen in methylxanthine-treated infants while effects of doxapram on the cerebral perfusion have not been studied yet. PATIENTS AND METHODS: Fifteen preterm infants treated with doxapram were included in the study. Birth weight ranged from 380 g to 1150 g (median 740 g), gestational age from 24 to 27 weeks (median 26 weeks). Infants received a doxapram loading dose (2.5 mg/kg) over a 30-minute period, followed by a continuous infusion of 0.5 mg/kg/h. Using Doppler sonography, blood flow velocities and the resistance index were measured in the anterior cerebral artery. Measurements were performed at baseline and 30 and 120 minutes after the start of doxapram. RESULTS: Maximal systolic blood flow velocity (V(max)) decreased significantly after the infants had received the loading dose (V(max) baseline: 40.7 cm/s +/- 6.9 [mean +/- SD]; V(max) 30 min: 35 cm/s +/- 8.9; p = 0.0017) but returned to near baseline values at 120 min (38.5 +/- 9.0, p = 0.22). End-diastolic, time-averaged, and time-averaged maximal velocities did not change significantly at 30 or 120 min. CONCLUSIONS: Doxapram induced a significant decrease in maximal cerebral blood flow velocity. Further studies are needed to assess whether this decrease may be critical to cerebral white matter perfusion in the vulnerable preterm infant.

Anterior Cerebral Artery↗
PubMed2004

Ginkgo biloba special extract EGb 761 in the treatment of peripheral arterial occlusive disease (PAOD)--a review based on randomized, controlled studies.

OBJECTIVE: The present review gives an overview and evaluation of clinical studies proving the efficacy of EGb 761 in patients with PAOD. METHODS: Relevant original papers and reports on this topic were identified by means of a literature search. Only randomized, double-blind, placebo-controlled clinical trials in patients with the indication peripheral arterial occlusive disease in stage II according to Fontaine were included (only treatment with the oral form of EGb 761). For the selected studies the ratio theta of the walking distance between EGb 761 and placebo was calculated and a test for relevant superiority of EGb 761 was performed (according to the guidelines of the Deutsche Gesellschaft für Angiologie (German Society of Angiology) [Heidrich et al. 1996]). Furthermore, a pooled estimation of the ratio was carried out. RESULTS: Nine studies complied with the criteria. The methodological quality and design of the trials were heterogeneous. In the majority of the studies, there was an advantage of EGb 761 in the increase of pain-free walking distance compared to placebo. For 7 studies, the advantage was found to be statistically significant. Testing the relevant superiority showed a significant result in 6 of the selected studies. The pooled estimator of the ratio amounts to theta = 1.23 (95% CI: 1.16, 1.31) and demonstrates the efficacy of EGb 761 over placebo as well. CONCLUSIONS: This review confirms the efficacy of Ginkgo biloba special extract EGb 761. It demonstrates not only the statistical significance of the difference with respect to placebo but also the clinical relevance for the treatment of patients with PAOD.

Arterial Occlusive Diseases↗
PubMed2001

Prophylactic urgent revascularization of the internal carotid artery in the symptomatic patient.

BACKGROUND: The symptomatic patient showing a string sign or ulcerative stenosis of the internal carotid artery (ICA) is subject to a high risk of arterial thrombosis or persisting intracranial embolization during the waiting period before operative revascularization. PATIENTS AND METHODS: During one year 186 operative revascularization procedures of the ICA were performed on the symptomatic patient. 26 of them fulfilled the prophylactic urgency criteria: symptoms of the cerebrovascular insufficiency and a string sign or ulcerative stenosis of the ICA with ulceration greater than 2 mm in depth. These results were compared to the control group of the 157 procedures under elective circumstances. RESULTS: Mean clamping time of the urgency and the elective patients were 23.8 min vs. 24.5 min and operation time 50.1 min vs. 54.3 min. None of our urgency patients presented new neurological defects in the postoperative phase, while this occurred in 3.8% in the elective group. Mortality rate in the elective group was 2.7% and 0% in the urgency group. Furthermore, there were fewer local complications in the urgency group. CONCLUSION: The urgent indication for the desobliteration of the ICA showing a symptomatic string sign or ulcerative stenosis can be recommended. Early thrombosis or neurological defects during the waiting period may be prevented without increasing complication rates.

Aged↗
PubMed2000

Effect of surfactant administration on cerebral haemodynamics and oxygenation in premature infants--a near infrared spectroscopy study.

OBJECTIVES: The aim of this study was to assess changes in cerebral haemodynamics and oxygenation induced by surfactant administration using near infrared spectroscopy (NIRS). METHODS: Eighteen premature infants, mean birth weight 960 g (range 550-1560 g), mean gestation age 28 weeks (range 25-30 weeks), were studied during 27 surfactant administrations. Porcine surfactant was administered to treat respiratory distress syndrome in a bolus of 100 mg/kg. Manual bag ventilation was performed for one minute after instillation. Heart rate, arterial oxygen saturation measured by pulse oximetry, transcutaneous PO2 (TcPO2), and PCO2 (TcPCO2), blood pressure, and cerebral oxygenated (O2Hb), deoxygenated (HHb), and total haemoglobin (tHb) concentration changes obtained by NIRS were registered every second from 15 minutes before until 30 minutes after surfactant administration. RESULTS: During surfactant administration, there was a short-lasting but significant drop in heart rate and arterial oxygen saturation. NIRS parameters remained constant during and up to 1 minute after administration. One to three minutes after administration, heart rate, oxygen saturation, and TcPO2 increased significantly concomitantly with an increase in O2Hb and a decrease in HHb. In 10 cases, TcPO2 increased above 100 mmHg. tHb--indicative of cerebral blood volume--did not change significantly. Five to 30 minutes after surfactant administration there was no difference of monitoring data from baseline levels. TcPCO2 and blood pressure remained unchanged during the measurement period. CONCLUSION: Cerebral blood volume remained constant in very-low-birth-weight infants when surfactant was administered by bolus administration followed by manual ventilation according to our protocol. Attention should be directed towards rapid adaptation of inspiratory oxygen concentrations after surfactant administration to avoid hyperoxaemia.

Brain↗
PubMed2000

Carotid endarterectomy prior to major abdominal aortic surgery.

BACKGROUND: Major aortic surgery carries a high risk of stroke. Carotid artery occlusive disease (CAOD) has been identified as one of the contributing risk factors. Regarding the long-term prevention of stroke, carotid endartectomy (CEA) seems to be superior to the best medical treatment in patients with high-grade CAOD. However, the role of CEA prior to major aortic surgery has not been studied. METHODS DESIGN: Prospective study, observational design. SUBJECTS AND SETTING: 201 patients referred to a community hospital for major aortic surgery. INTERVENTION: The patients were non-invasively screened by continuous-wave and duplex Doppler ultrasonography for the presence of CAOD. In 41 patients with angiographically confirmed high-grade CAOD, CEA was performed prior to major aortic surgery. MAIN OUTCOME MEASURE: Combined mortality and major morbidity from CEA and abdominal aortic surgery. RESULTS: There was no mortality or morbidity related to CEA. Total perioperative mortality related to major aortic reconstruction was 3.5%. No new perioperative focal neurologic deficits occurred except for one fatal stroke in a patient in whom CEA had been judged not to be indicated. CONCLUSIONS: CEA can be performed safely prior to major aortic surgery resulting in excellent overall neurologic outcome in patients with high-grade CAOD. We propose that patients scheduled for major aortic surgery be screened for the presence of high-grade CAOD and that CEA be performed first, if indicated according to published guidelines.

Adult↗
PubMed2000

Umbilical artery catheter blood sampling decreases cerebral blood volume and oxygenation in very low birthweight infants.

UNLABELLED: The aim of this study was to assess whether blood sampling from umbilical artery catheters reduces cerebral blood volume and cerebral oxygenation in very low birthweight infants. A total of 20 infants, median birthweight 890 g (530-1,500 g), median gestation age 26 +4 wk (range: 22 +5 to 30 +6 wk) were studied from 10 min before until 10 min after routine blood sampling from umbilical artery catheters placed in the high position. Using near infrared spectroscopy, changes in concentrations of cerebral oxygenated and deoxygenated haemoglobin were measured, and changes in cerebral blood volume and cerebral oxygenation index were calculated. Heart rate, oxygen saturation, transcutaneous PO2 and PCO2 were registered continuously. Mean arterial blood pressure was measured before and after sampling. Oxygenated haemoglobin decreased significantly from baseline during blood sampling, whereas deoxygenated haemoglobin did not change significantly. This resulted in a decrease in cerebral blood volume and cerebral oxygenation index. Heart rate increased slightly, but significantly, from baseline. Oxygen saturation, blood pressure, transcutaneous PO2 and PCO2 did not change significantly. CONCLUSION: Blood sampling from umbilical artery catheters induces a significant decrease in cerebral blood volume and cerebral oxygenation.

Analysis of Variance↗
PubMed1999

Eversion endarterectomy versus open thromboendarterectomy and patch plasty for the treatment of internal carotid artery stenosis.

OBJECTIVE: in 1996 we changed our treatment for stenosis of the internal carotid artery (ICA) from open thromboendarterectomy and PTFE-patch plasty (TEA) to eversion endarterectomy (EEA). DESIGN: retrospective study. METHODS: a total of 475 EEAs of the ICA were performed between 2/96 and 11/96. These results were compared to the results of TEA carried out between 2/94 and 11/94 (n=388). RESULTS: clamping and operation time were significantly shorter for EEA. Neurological complications included transient ischaemic attacks in 1. 0% in the EEA group versus 1.3% after TEA (p=0.72), minor strokes (0. 6% vs. 1.8%, p=0.10) and major strokes in 1.5% versus 1.1% (p=0.59). The rate of restenosis >50% was 2.5% after EEA and 10.2% after TEA. The only detectable difference of statistical significance in complication rates was in the lesions of the hypoglossal nerve (5.3% vs. 2.6%, p=0.04). CONCLUSIONS: EEA of the ICA is a safe procedure for carotid reconstruction with the additional advantages of short clamping time, possibility of simultaneous shortening of an elongated ICA, and no requirement for patching.

Adult↗
PubMed1998

Ultrasonography in suspected acute appendicitis in childhood-report of 1285 cases.

OBJECTIVE: For the assessment of the diagnostic value of real-time ultrasonography (US) in children with suspected acute appendicitis (a.A.) the results of graded compression US are compared with clinical and histological final diagnoses. METHODS: In a prospective study over nearly 9 years we examined 1285 children aged 1-15 years (m=514, f=771). Using a 5-MHz curved array transducer the right lower quadrant was examined in a graded compression technique. RESULTS: Prevalence of histologically proven a.A. was remarkably low (9%). In diagnosis of acute appendicitis in childhood US achieves a sensitivity of 92%, specificity of 98%, a positive predictive value of 90% and a negative predictive value of 98%. The overall accuracy was 98%. Mesenteric lymphadenitis was seen in 181 cases (prevalence 12%) and terminal ileitis occasionally accompanied by mesenteric lymphadenitis was seen in 116 cases (prevalence 9%). CONCLUSION: In children with suspected appendicitis US of the abdomen gives great diagnostical value for differential diagnosis of a.A. and other more frequent inflammatory diseases of the ileocoecal region. Thus US provides further reliable information to the referring physician. Consequently it is necessary to perform US in each child with acute abdominal pain, even if clinical diagnosis seems to be well established.

Acute Disease↗
PubMed1998

Low-dose iloprost infusions compared to the standard dose in patients with peripheral arterial occlusive disease Fontaine stage IV. DAWID Study Group.

BACKGROUND: Intravenous iloprost, titrated from 0.5 up to 2.0 ng/kg/min has been shown in patients with PAOD III/IV to significantly improve healing of trophic lesions, relief of rest pain, and reduce the rate of major amputation or death at 6 months as compared to placebo. The effect is considered related to improvement of the microcirculation. The aim of the present trial was to identify an optimum dose regarding treatment response and tolerability, by studying 4 doses of 25, 50, 75 and 100 micrograms iloprost daily. PATIENTS AND METHODS: 302 patients with PAOD IV were randomised via a double-blind fashion to one of the 4 doses. The primary endpoint was the responder rate at end of treatment. Responders were defined as patients with very good or good global efficacy, as judged by lesion healing and pain relief. Side effects were documented and a pre-defined benefit/risk index was calculated. RESULTS: No dose-dependency of iloprost regarding primary or secondary endpoints was observed. The rate of responders ranged between 48.7-53.5%. Side effects, mainly related to vasodilation, increased dose-dependently (p < 0.001, chi 2-test), with a significant decrease of the benefit/risk index from 2.19 +/- 1.19 to 1.64 +/- 0.97 (p = 0.012, ANOVA). Responders had a better outcome at 6 months than non-responders (2.6 fold higher rate of major amputation or death; life table analysis). CONCLUSIONS: It is concluded that iloprost should be titrated to the optimum rather than maximum tolerated dose, since a higher incidence of side effects not associated with an increased treatment response was observed at higher doses.

Aged↗
PubMed1997

Cardiac risk stratification for high-risk vascular surgery.

BACKGROUND: The best strategy for cardiac risk assessment before high-risk vascular surgery remains controversial. A cardiac risk stratification protocol was evaluated in patients undergoing high-risk vascular surgery. Our investigation paralleled the elaboration of the American College of Cardiology/ American Heart Association (ACC/AHA) Guidelines for Perioperative Cardiovascular Evaluation for Noncardiac Surgery and is highly comparable to the proposed guidelines. METHODS AND RESULTS: A cardiac risk stratification protocol was evaluated prospectively in 203 patients scheduled for aortic surgery. Key points of the study were cardiac mortality/morbidity and cost-effectiveness. Patients were stratified into low (n = 101), intermediate (n = 79), and high (n = 23) cardiac risk after clinical predictors. After stratification, the degree of estimated functional capacity assessed by treadmill exercise and daily living activities and expressed by metabolic equivalents (METs) was critical for further cardiac evaluation. In intermediate-risk patients with an estimated functional capacity < 5 METs and in all high-risk patients, noninvasive cardiac testing and/or subsequent medical care were performed. Noninvasive testing was considered necessary in 41 patients, coronary angiography in 7, and myocardial revascularization in 1. Overall hospital mortality was 3.5%. Cardiac mortality and morbidity were 1% and 12.4%, respectively. CONCLUSIONS: Cardiac risk stratification for high-risk vascular surgery patients, according to a protocol similar to the ACC/AHA Guidelines for Cardiovascular Evaluation for Noncardiac Surgery, demonstrated excellent clinical outcome. This approach appears to be a safe and economical strategy for preoperative cardiac evaluation.

Aorta↗
PubMed1997

Efficacy of a new prostaglandin E1 regimen in outpatients with severe intermittent claudication: results of a multicenter placebo-controlled double-blind trial.

For the first time efficacy and safety of a new prostaglandin E1 (PGE1) regimen in the treatment of intermittent claudication were evaluated in a randomized, double-blind, placebo-controlled multicenter clinical trial. The study involved 213 outpatients with a maximum walking distance of 50 to 200 m measured on the treadmill (3 km/hr, 12% grade). After a 2-week run-in phase they received a 2-hour intravenous infusion of 60 micrograms PGE1 or placebo 5 days a week for 4 weeks. It was followed by a 4-week interval treatment with the same medication administered only twice a week. Patients were monitored for 3 months when they received no study medication. In the PGE1 group the intention-to-treat analysis (n = 208) revealed an increase in walking distance after 4 weeks of 75% (placebo, 43%). At the end of the interval treatment the walking distance had improved to 101% (placebo, 60%). The results remained virtually constant during follow-up (PGE1, 104%, placebo, 63%). Between-group comparisons showed significant differences in favor of PGE1 for all three time points of measurement (p < 0.05, p < 0.01, and p < 0.05). PGE1 was well tolerated; the rate of adverse reactions related to the treatment was 12.8% (placebo, 7.7%). In summary, these results show that the new PGE1 regimen is effective and safe in the treatment of outpatients with intermittent claudication.

Aged↗
PubMed1997

Improvement in the quality of life after i.v. PGE1 therapy for intermittent claudication.

BACKGROUND: Increasingly and justifiably, clinical studies are now being expected to investigate the influence of therapeutic measures also on the quality of life of the patient. PATIENTS AND METHODS: Since no data on the variability of changes in the quality of life of the patient following PGE1 treatment are so far available, the initial investigation was designed as an uncontrolled pilot study. 104 patients (median age 64.5 years) with a maximum of walking distance on the treadmill (3 km/12%) of 50-250 m were included and given a daily intravenous infusion of 60 micrograms PGE1 (Prostavasin) over a period of 4 weeks excluding weekends. This was followed by a treatment-free follow-up period of 3 months. Changes in the quality of life were recorded with both the newly developed disease-specific questionnaire PAVK-86, and the generic questionnaire SF 36; in addition, the pain-free and maximum walking distances on the treadmill were also established prior to and immediately following treatment, as also at the end of the follow-up period. RESULTS: The quality of life was significantly improved in all dimensions (functional status, complaints, pain, mood, anxiety, social life, treatment expectations) in addition to a marked increase in the median pain-free walking distance from 77 to 108 m (p < 0.001) and the maximum walking distance from 118 to 171 m (p < 0.001). At the end of the 3-month observation period, the improvement was essentially still demonstrable. CONCLUSION: The study has shown for the first time that treatment with intravenous PGE1 brings about not only the already known increase in the walking distance, but also a clinically relevant and significant improvement in the patient's quality of life.

Adult↗
PubMed1997

[Intraoperative lysis and neurostimulation as added therapy in surgery of popliteal artery aneurysm].

Additional therapy of symptomatic popliteal artery aneurysm includes intraoperative lysis for the treatment of the descending thrombosis and spinal cord stimulation for cases of chronic deterioration of the peripheral perfusion state. Between 1989 and 1996, we treated 50 patients with 55 symptomatic aneurysms using this concept, 18 of them as emergency cases. We reached a postoperative amputation rate of 12.7% and good long-term functional results in 34 of 37 patients.

Aged↗
PubMed1996

Intraoperative autotransfusion in aortic surgery: comparison of whole blood autotransfusion versus cell separation.

OBJECTIVE: Differences concerning alteration of hemostatic, hemolysis, and hematologic parameters after transfusion of blood from a cell-separation (CS) device or whole blood autotransfusion (WBA) were prospectively evaluated during major aortic surgery. METHOD: Thirty-two patients were randomly selected to receive autologous retransfusion by using either WBA or a CS device. Coagulation and hematologic parameters and levels of hemolytic degradation products (HDP) were assessed in the retransfused blood and in the patients' plasma preoperatively and until 24 hours after autologous retransfusion, respectively. RESULTS: Mean volume of retransfused blood was 1072 +/- 473 ml in the WBA group and 556 +/- 504 in the CS group. Level of HDP (bilirubin, free hemoglobin [free HB], and lactic dehydrogenase [LDH] and hemostatic disturbances (d-dimer value, fibrin degradation products) were significantly higher in the WBA device compared with the CS blood. Blood samples taken from the WBA group revealed significantly higher level of HDP (free HB, LDH) and of d-dimer values after autotransfusion compared with the CS group. CONCLUSION: Levels of HDP and the degree of hemostatic disturbances were significantly higher in retransfused whole blood compared with CS blood. Hemostatic disturbances and levels of HDP were significantly pronounced in the patients' plasma after WBA compared with CS. CS retransfused blood seems to be of superior quality compared with WBA and the degree of hemolysis and hemostatic disturbances is minor after CS retransfusion.

Aged↗
PubMed1996

Intraoperative use of somatosensory evoked potentials for brain monitoring during carotid surgery.

Somatosensory evoked potentials (SSEP) are a valuable clinical tool in the operating theater. Multichannel SSEP monitoring is an objective measure of CBF and cerebral function. The monitoring of the SSEP during carotid surgery is a simple and reliable method of determining the effect of carotid clamping on CBF and the need for shunting. The diagnosis sensitivity and specificity of intraoperative SSEP monitoring for assessing the neurologic outcome of patients are over 95%. At least 16.1% of cases required shunt placement using SSEP monitoring.

Brain↗
PubMed1996

Transcutaneous oxygen pressure as predictive parameter for ulcer healing in endstage vascular patients treated with spinal cord stimulation.

OBJECTIVE AND DESIGN: This study was designed to test the hypothesis that initial TcPO2 helps predict clinical outcome in vascular patients treated with spinal cord stimulation. A randomized-controlled study with one year follow-up was made in 86 Fontaine stage IV patients with endstage peripheral arterial occlusive disease (PAOD) undergoing 21 day intravenous prostaglandin E1 (PGE1) therapy for nonhealing ulcers. MATERIALS AND METHODS: All patients had arteriosclerosis, 13 also diabetes mellitus. Entry criteria included: non-reconstructible PAOD as proven by intra-arterial angiography or patient condition, ankle systolic pressure < 50 mmHg, severe rest pain despite analgetic medication, and presence of nonhealing foot ulcers or dry gangrene. One week after the start of PGE1 therapy, patients were randomized into receiving SCS plus PGE1 (n = 45 patients), or just PGE1 (n = 41 patients). Follow-up examinations were done at 1, 3, 6 and 12 months. BASELINE: There were no significant differences between both groups in the following: age, sex distribution, ischemic skin lesions, risk factors and several key group mean physiological values including ankle systolic pressure, ankle/brachial ratio (ABI) and foot TcPO2. The SCS group had more prior vascular leg surgeries (1.77 vs 1.58 per patient). RESULTS AT 12 MONTHS: There was significantly better total healing of foot ulcers in the SCS-group (69 vs 17%; p < 0.0001). Significantly more SCS-patients achieved an outcome of Fontaine stage II (claudication pain, no rest pain or lesions) (40 vs 10%, p = 0.0014). The frequency of minor and major amputations was not different, respectively 13 vs 15% and 16 vs 20%. The mean ABI at 12 months of the treated limb of the SCS-patients was not significantly greater. Foot TcPO2 increased significantly for the SCS-group (+213 vs -2%; p < 0.0001). Patients in either group whose TcPO2 rose to 26.0 +/- 8.6 mmHg on average were able to heal ulcers or toe amputation wounds. PGE1-patients had temporary TcPO2 elevations of about 33% on average but this was gone by six months. SCS-patients had steady increases in TcPO2, and maintained them at 12 months. Among the SCS-patients, those with baseline TcPO2 < = 10 mmHg had significantly less success at 12 months, this was not observed for the OMT-patients. The regional perfusion index increased significantly, 187 vs 0%; p < 0.001. CONCLUSIONS: Spinal cord stimulation appears to provide a major benefit for lesion improvement in stage IV patients with non-reconstructible PAOD. Patients with an initial TcPO2 > 10 mmHg will respond better to the stimulation therapy. With pain relief and ulcer healing quality of life improved. Effects on limb salvage do not appear.

Aged↗