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W Dietrich

Publications and source records attributed to W Dietrich.

At least 19 recordsLinked to original sources
PubMed2006

[Preoperative autologous blood donation in cardiac surgery. Reduction of allogeneic blood requirements].

BACKGROUND: Preoperative autologous blood donation is an effective method to reduce allogeneic transfusion requirement. However, this method is only rarely utilized in cardiac surgery. Besides economic concerns one essential argument against predonation is the lack of sufficient time due to the short waiting lists. The aim of the present study was to investigate the efficacy of autologous predonation to reduce allogeneic blood transfusion in routine cardiac surgery on a center without longer preoperative waiting lists. PATIENTS AND METHODS: A total of 2,626 cardiac surgery patients were included. Primary endpoint of the study was the perioperative incidence of allogeneic packed cell transfusion. If time between diagnosis and admission to the hospital was >10 days, predonation was offered to the patients. Data were stratified for preoperative risk score. Logistic and linear regression analysis tested the influence of different variables on the incidence of allogeneic blood transfusion and the total amount of allogeneic blood. RESULTS: Of all patients 267 (11.2%) underwent predonation. The incidence of allogeneic packed cell transfusion was reduced from 53% to 19% by autologous predonation (p<0.001). The total amount of allogeneic blood transfused was significantly different between the groups (2.2+/-4.2 vs. 0.84+/-6.3 units; p<0.001). DISCUSSION: Autologous predonation in cardiac surgery was effective in reducing blood transfusions even in the absence of longer preoperative waiting times. It is a safe and effective method to minimize blood transfusion in cardiac surgery.

Aged↗
PubMed2005

[The Anaesthesiological Questionnaire for patients in cardiac anaesthesia. Results of a multicenter survey by the scientific working group for cardiac anaesthesia of the German Society for Anaesthesiology and Intensive Care Medicine].

OBJECTIVE: The Anaesthesiological Questionnaire (ANP) is a self-rating method for the assessment of postoperative complaints and patient satisfaction. The questionnaire was adapted for use in cardiac anaesthesia (ANP-KA). The study was conducted to show the value of ANP-KA as a practicable means of assessing the patient's state after cardiac anaesthesia and for its use in quality assurance. METHODS: A total of 1,688 patients from 19 clinics were included who had exclusively received heart valve surgery, CABG surgery or both operations. They completed the ANP-KA between days 1 and 8 postoperatively. RESULTS: The ANP-KA was completed by 79.1% of the patients without any assistance. The highest incidence rates were reported for a dry mouth/thirst (85.1%) and for pain in the area of surgery (60.2%). Plausible and significant differences in patients' symptoms between the grading for the immediate postoperative period and the current state at filling in the questionnaire were found. Women reported more postoperative complaints than men but no differences were found between male and female patients with regard to satisfaction with anaesthesiological care and convalescence. More complaints were reported after heart valve surgery than after CABG and satisfaction with convalescence was significantly lower after heart valve surgery. The clinics differed with respect to the reported somatic complaints and satisfaction scales. CONCLUSION: The results demonstrate the practicability and validity of the ANP-KA for the assessment of postoperative complaints and patient satisfaction after cardiac surgery.

Adult↗
PubMed2004

[Novel calcium phosphate formula for filling bone defects. Initial in vivo long-term results].

BACKGROUND: Up to now hydroxyapatite (HA) and beta-tricalciumphosphate (beta-TCP) ceramics have been routinely sintered at temperatures between 1100 degrees and 1500 degrees C. Our new calcium ceramic is fabricated by a sol-gel process at 200 degrees C. The aim of this investigation was to test the biodegradation of and the induction of bone formation by this material. MATERIAL AND METHODS: Eighteen 1-year-old Goettingen minipigs were divided into three groups. Critical size defects (>5 cm(3)) in the mandible were treated differently in all three animals (group 1: filling with 40% beta-TCP plus 60% HA, group 2: pure HA was applied, group 3 served as controls: only gelatinous material was given). Macroscopic and microscopic investigations of the former defects were made 8 months postoperatively. RESULTS. In groups 1 and 2 biodegradation of more than 93% of the new calcium phosphate formula was found 8 months postoperatively and considered to be very good. No difference was observed between pure HA (group 2) and the combination of HA and beta-TCP (group 1). In both groups complete bone formation was seen macroscopically in the former defects. In the control group only incomplete bone formation with 48.4% of the defect area was noted. This difference was significant ( p<0.001). DISCUSSION: The new calcium phosphate formula made by a sol-gel method at 120 degrees C seems to be suitable for filling bone defects and is of interest for orthopedic surgery, traumatology, craniomaxillofacial surgery, and dentistry.

Absorbable Implants↗
PubMed2003

[Neurological complications of inflammatory intestinal diseases].

A number of neurological symptoms have been described as complications of inflammatory bowel disorders such as coeliac disease, Whipple's disease, Crohn's disease and ulcerative colitis. The neurology of coeliac disease includes disorders of the central nervous system encompassing cerebellar ataxia, epilepsy, myoclonus, dementia and multifocal leukoencephalopathy. Peripheral neuropathies, of axonal and demyelinating types, and myopathies have also been reported. The pathomechanisms are more related to immunological-inflammatory processes than to a malresorptive vitamin deficiencies. While CNS symptoms of coeliac disease show a poor response to gluten restriction, peripheral symptoms may respond to elimination of gluten from the diet. There are few reports of a successful corticosteroid treatment in patients showing inflammatory findings in the CSF or bioptic material. Whipple's disease is caused by the gram-positive bacillus Tropheryma whipplei. Patients with a central nervous system manifestation of Whipple's disease may develop a variety of symptoms including dementia, supranuclear gaze palsy, movement disorders, hypothalamic dysfunction and myorhythmia. The CNS-infection is diagnosed by PCR of the CSF. Long-term antibiotic treatment is required, and relapses may occur after withdrawal of antimicrobial therapy. Crohn's disease and ulcerative colitis are complicated by various forms of polyneuropathies, and arterial and venous cerebrovascular diseases. In most cases with neurological complications of inflammatory gastrointestinal diseases an immune mediated inflammatory process is suspected to be the underlying pathomechanism.

Aged↗
PubMed2002

Fulminate intracardiac thrombosis associated with Budd-Chiari-syndrome and inferior vena cava thrombosis.

The most common cause of edema of the legs and dyspnea is congestive heart failure. Further differential diagnosis such as renal or hepatic failure have to be considered. We report the case of a previous healthy 65-year-old woman who developed dyspnea and massive edema of the legs followed by acute hepatic and renal failure. Imaging studies showed a thrombosis of the inferior vena cava (IVC) caused by a tumor between the right kidney and the IVC. Histological examination revealed a leiomyosarcoma of the IVC. Hepatic failure due to venous outflow obstruction (Budd-Chiari syndrome, BCS) was diagnosed. Coagulation profile showed a complex disorder due to acute hepatic failure. Factor V Leiden and prothrombin gene mutation G20210A could be excluded. The thrombosis extended from the femoral veins up to the right atrium. After 11 days of anticoagulation with heparin platelet counts decreased by more than 50%. Suspecting a heparin-induced thrombocytopenia the patient was placed on recombinant hirudin (lepirudin) for anticoagulation. Hepatic venogram showed a thrombosis of the hepatic vein orifices but not of the hepatic veins. The tumor and the thrombi were removed surgically. When the cardiopulmonary bypass was terminated new intracardiac thrombi occurred. Despite immediate surgical intervention the patient finally died due to right ventricular failure caused by the fulminate intracardiac thrombosis. In conclusion, thrombosis of the IVC may mimic congestive heart failure and may cause BCS. Neoplasms and coagulation disorders may cause thrombosis of the IVC.

Aged↗
PubMed2001

Posthemorrhagic hydrocephalus in preterm infants: long-term follow-up and shunt-related complications.

INTRODUCTION: A retrospective analysis of 42 preterm infants with intraventricular hemorrhage was performed in order to evaluate shunt-related problems in neonates with posthemorrhagic hydrocephalus. PATIENTS AND METHODS: Within the last 15 years, 76 infants with intraventricular hemorrhage were treated primarily by external ventricular drainage, and 42 needed permanent shunting. Shunting was performed 28-101 days after the patients' birth, ventriculoatrial shunts being placed in 10 patients and ventriculoperitoneal shunts in 32. RESULTS: The mean number of shunt revisions per patient was 1.57. The main reasons for shunt revision were infection (7.1%) and blockage (45.2%). Primary ventriculoperitoneal and ventriculoatrial shunts differed only insignificantly in revision rate and length of shunt survival, whereas ventriculoperitoneal shunts used in shunt revisions required significantly fewer further revisions. CONCLUSIONS: The neurological outcome was not related to the necessity for or to complications of a shunt. Programmable valve systems and neuroendoscopy appear to be helpful in the overall management and in the treatment of complications.

Brain Damage, Chronic↗
PubMed2001

[Angina pectoris emergency. Ambulatory assessment or patient admission?].

Provision of medical help for acute angina pectoris must take its cue from the severity of the symptoms and the probability that coronary artery disease actually is present. The therapeutic possibilities range from clarification of the situation in the office to immediate initiation of treatment and hospitalizing the patient in the company of an emergency physician. In addition to changes in lifestyle and diet, treatment options for coronary artery disease include the elimination of risk factors, symptomatic treatment with nitrates, molsidomine, beta blockers, and calcium antagonists, percutaneous transluminal coronary angioplasty and coronary artery bypass surgery.

Aged↗
PubMed2001

Gamma knife radiosurgery of acoustic neurinomas.

The authors report on their series of 40 patients with 41 acoustic neurinomas (ACNs), including one patient with bilateral acoustic neurinomas suffering from neurofibromatosis type 2 (NF II) who were treated with the gamma knife unit at their institution between August 1992 and October 1995. Of these 41 tumours, 21 ACNs had been operated on before (1 to 4 times), 20 ACNs were exclusively treated by gamma knife radiosurgery (GKRS). The maximal axial tumour diameter ranged from 6 to 33 mm (median: 25 mm), the maximal transverse tumour diameter ranged from 7 mm to 36 mm (median: 16 mm). The dose distributed to the tumour margin was 10 to 17 Gy (median: 12 Gy) by enclosing the tumour with the 40% to 95% isodose line (median: 50% isodose line) and using 1 to 12 isocenters (median: 5 isocenters). Central loss of contrast enhancement was observed in 78% of the patients within six to 12 months after radiosurgery. Thirty-two patients were observed over a minimum follow up period of at least 36 months, 9 patients were lost to follow up as they died of unrelated causes or refused further check-ups. Within the follow up period of up to seven years, magnetic resonance imaging (MRI) control scans revealed the tumour diameter stable or decreased in 29 cases and increased in three tumours. Of 14 patients with useful hearing before treatment, 9 patients were examined in addition to pure tone audiogramm by measurement of brainstem auditory evoked potentials (BAEPs) one to four years after radiosurgery. None of these patients showed a postoperative loss of the cochlea function. According to slight alterations of the cochlea function (cochlea summating action potential), pure tone audiometry of those patients revealed only slight changes of the hearing level (HL) within a maximum range of +/-15 Decibel (dB). The hearing threshold improved in two, was stable in four and deteriorated in three patients, respectively. We observed postradiosurgical aggravation of a pre-existing facial weakness in two out of 13 patients, a new occurrence of facial palsy was seen in two cases (four years after treatment), one of them was previously operated on and both suffered from cystic degeneration with mass effect. Tinnitus improved in six out of 13 patients, deteriorated in two and never appeared as a new permanent sequela. Trigeminal hypaesthesia did also not appear as a new permanent symptom, improved in three out of 9, and deteriorated in one out of 9 patients. Vertigo increased in six out of 23, was stable in 8 and decreased in nine out of 23 patients each. GKRS proves to be a safe and highly satisfactory therapeutical option or addition to open surgery, especially for radiologically verified regrowing residual ACNs, but also as primary treatment in selected patients. A high rate of tumour control can be achieved with an acceptable rate of neurological deficits.

Adult↗
PubMed2001

Epidural metastasis of a glioblastoma after stereotactic biopsy: case report.

Tumor seeding along the biopsy tract is a rare complication in stereotactic biopsy. We present the unique case of a 42-year-old male with epidural tumor seeding along the needle tract after computer tomography-guided stereotactic biopsy of a glioblastoma in the right basal ganglia. Three months after the biopsy and one week following fractionated radiation therapy, the patient died of brain edema and cardiac dilatation. Besides further tumor growth at the primary site, autopsy revealed a right frontal epidural, nodular metastatic tumor at the site of dura incision of the stereotactic biopsy. Histological examination showed a glioblastoma that spread epidurally along the needle tract. This is the first report of an epidural intracranial implantation metastasis of a glioblastoma after stereotactic biopsy.

Adult↗
PubMed2001

Treatment of dural arteriovenous fistulae (dAVF's) at the superior sagittal sinus (SSS) using embolisation combined with micro- or radiosurgery.

DAVF's at the SSS are extremely rare and usually present with intracranial haemorrhage (ICH) or a progressive neurological deficit. Due to their midline location and multiple arterial supply, endovascular treatment alone often fails in eliminating the fistula. Therefore, endovascular, combined with neurosurgical and/or radiosurgical treatment is often needed to cure the patient. We summarized our experience with three male patients over a ten-year period who suffered from dAVF's involving the middle and posterior third of the SSS. Two of them presented with an ICH during the clinical course. Despite multiple transarterial embolisations, complete fistula occlusion could not be achieved in any of them. Nevertheless, neurological symptoms improved in all cases. One patient refused further treatment and died six years later due to an ICH. Another patient was finally cured by microsurgical coagulation of the fistula. In the remaining patient stereotactic radiosurgery (SRS) was performed after nearly complete endovascular occlusion. We strongly recommend microsurgery and/or radiosurgery as adjunctive measures, if embolisation alone fails to eliminate these dangerous fistulae.

Aged↗
PubMed2001

Low preoperative antithrombin activity causes reduced response to heparin in adult but not in infant cardiac-surgical patients.

UNLABELLED: We evaluated the interaction of preoperative antithrombin (AT) activity and intraoperative response to heparin in cardiac surgery. Heparin anticoagulation is essential during cardiopulmonary bypass (CPB). Heparin itself has no anticoagulant properties, however it causes a conformational change of the physiologic plasma inhibitor AT that converts this slow-acting serine protease inhibitor into a fast acting one. Thus, adequate AT activity is a prerequisite for sufficient heparin anticoagulation. AT activity is reduced by long-term heparin therapy. This prospective, observational study investigated 1516 consecutive cardiac-surgical patients (1304 patients >1 yr (Group A) and 212 patients < or = 1 yr (Group I)). AT activity was measured the day before surgery by a chromogenic substrate assay. The celite-activated activated clotting time (ACT) was used to guide intraoperative heparin administration. Heparin sensitivity was calculated and the postoperative blood loss and perioperative blood requirement was recorded. Infant patients had significantly less preoperative AT activity compared with older patients: 84 (33)% vs 97 (17)%, median (interquartile range) (P < 0. 05). The subgroup of patients aged <1 mo (n = 64) demonstrated a preoperative AT activity of 56 (27)% as compared with 90 (23)% in infant patients between one month and one year (n = 148). In adult patients, preoperative AT activity depended predominantly on preoperative heparin treatment: 62% of the patients with an AT activity <80% were pretreated with heparin. Five minutes after heparin but before CPB the ACT was 587 (334) s in Group A patients with AT activity > or = 80%, and 516 (232) in patients with AT activity < or = 80% (P < 0.05). The target ACT of 480 s was achieved in 70% of patients with normal AT activity in Group A compared with only 54% of patients with AT activity <80% (P < 0.05). In Group A patients with decreased AT activity, 18% demonstrated an inadequate ACT response-defined as ACT <400 s-to the first bolus injection of heparin. In Group I, preoperative AT activity did not influence the ACT response (ACT 5 min after heparin: 846 [447] s in patients with AT activity > or = 80% vs 1000 [364] s in patients with decreased AT activity). The heparin sensitivity was 2.4 (1.1) s/unit heparin/kg compared with 1.5 (0.8) s/unit heparin/KG in group A (P < 0.05). These results suggest that preoperative diminished AT activity causes reduced response to heparin in adult but not in infant patients. Infant patients demonstrate a higher heparin sensitivity despite lower preoperative AT activity. Measurement of preoperative AT activity identifies adult patients at risk of reduced sensitivity to heparin. IMPLICATIONS: In patients less than one year of age, low antithrombin (AT) activity is caused by the immature coagulation system. Despite low AT activity, these young patients demonstrate a normal or increased response to heparin anticoagulation before cardiopulmonary bypass (CPB). In contrast, in patients older than one year of age and adult patients decreased preoperative AT activity is mainly caused by preoperative heparin therapy and causes insufficient response to heparin anticoagulation with a standard heparin dosage. Measurement of preoperative AT activity identifies patients at risk of inadequate anticoagulation during CPB.

Adolescent↗
PubMed2001

Anaphylactic reactions to aprotinin reexposure in cardiac surgery: relation to antiaprotinin immunoglobulin G and E antibodies.

BACKGROUND: Aprotinin, a serine proteinase inhibitor, reduces bleeding during cardiac surgery. As aprotinin is derived from bovine lung, it has antigenic properties. This investigation examined the incidence of anaphylactic reactions in patients reexposed to aprotinin and the relation to preformed antiaprotinin immunoglobulin (Ig)G and IgE antibodies. METHODS: This prospective observational study conducted at five centers in Germany evaluated patients undergoing repeat cardiac surgery reexposed to aprotinin between 1995 and 1996. Antiaprotinin IgG and IgE antibody measurements, using a noncommercial enzyme-linked immunosorbent assay and an immunofluorescence assay, respectively, were performed preoperatively and postoperatively. An anaphylactic reaction was defined as major changes from baseline within 10 min of aprotinin administration of systolic pressure 20% or greater, heart rate 20% or greater, inspiratory pressure greater than 5 cm H2O, or a skin reaction. RESULTS: In 121 cases (71 adults, 46 children), a mean aprotinin reexposure interval of 1,654 days (range, 16-7,136 days) was observed. Preoperative antiaprotinin IgG (optical density ratio > 3) and IgE antibodies (radioallergosorbent test [RAST] score < 3) were detected in 18 and 9 patients, respectively. High concentrations of each (IgG, optical density ratio > 10; IgE, RAST score > or = 3) were detected in five patients. Three patients (2.5%; 95% confidence interval, 0.51-7.1%) experienced an anaphylactic reaction after aprotinin exposure, followed by full recovery; these patients had reexposure intervals less than 6 months (22, 25, and 25 days) and the highest preoperative IgG concentrations of all patients (P < 0.05). Assay sensitivity was 100%, as no anaphylactic reactions occurred in IgG-negative patients (95% confidence interval, 0.0-3.1%); assay specificity was 98%. Preoperative IgE measurements were quantifiable in two of three reactive patients and in three nonreacting patients. CONCLUSIONS: Quantitative detection of antiaprotinin IgE and IgG lacks specificity for predictive purposes; however, quantitation of antiaprotinin IgG may identify patients at risk for developing an anaphylactic reaction to aprotinin reexposure.

Adolescent↗