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R Mertens

Publications and source records attributed to R Mertens.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Inferior vena cava filters. Indications and results in 111 patients].

BACKGROUND: Anticoagulation is the treatment of choice for deep vein thrombosis and pulmonary embolism. Occasionally this treatment is contraindicated or fails to prevent pulmonary embolism. In these patients, inferior cava vein interruption is indicated and filter insertion is the procedure commonly performed. AIM: To report the results of inferior cava vein filter insertions in 111 patients. PATIENTS AND METHODS: A retrospective review of patients in whom inferior cava vein filters were inserted was performed. RESULTS: During the period 1983-1997, filters were inserted in 111 patients (56 female) aged 15 to 93 years old. Indications were pulmonary embolism with contraindication or failure of anticoagulation therapy or poor respiratory function (58 patients), deep vein thrombosis and contraindication for anticoagulation (32 patients) and other indications in 20 patients. In 47 patients, treated before 1993, the insertion required a cut-down. Since then, a percutaneous approach was used in the remaining 64 cases. Three insertion attempts failed, all using cut-down. One of these patients died due to a massive pulmonary embolism. In 88% of the patients the jugular vein was the access site and in 10 patients, the filter was deliberately deployed above the renal veins. There was no mortality or complications. Patients were followed during a maximal period of 147 months and 27 died of unrelated disorders. Survival at 5 and 10 years was 63 and 47% respectively. Symptomatic inferior cava vein obstruction was detected in 5 patients during the follow up period. CONCLUSIONS: Inferior cava vein filter insertion is a safe measure to prevent pulmonary embolism and its consequences.

Adolescent↗
PubMed1997

Nasopharyngeal carcinoma in childhood and adolescence: concept and preliminary results of the cooperative GPOH study NPC-91. Gesellschaft für Pädiatrische Onkologie und Hämatologie.

BACKGROUND: The increasing use of chemotherapy has improved the prognosis of patients with nasopharyngeal carcinoma (NPC), and the authors demonstrated the beneficial effect of adjuvant interferon (IFN)-beta in a previous pilot study of children with advanced stage NPC. The current multi-institutional, cooperative GPOH (Gesellschaft für Pädiatrische Onkologie und Hämatologie) study NPC-91 was begun in 1992 to determine the efficacy of preradiation chemotherapy, radiotherapy, and adjuvant IFN-beta, in the treatment of advanced stage NPC. METHODS: Of a total of 22 patients, 21 had American Joint Committee on Cancer Stage III or IV disease, and 1 had Stage II disease. The median age was 12 years (range, 8-16 years). Twenty of 22 received 3 courses of preradiation chemotherapy consisting of methotrexate 120 mg/m2 on Day 1, cisplatin 100 mg/m2 on Day 1, and 5-fluorouracil 1000 mg/m2 for five days as well as 6 doses of leucovorin 25 mg/m2 every six hours beginning on Day 2. The Stage II patient received no chemotherapy, and chemotherapy was terminated for another during the first course. All patients had radiation therapy, stratified by stage. The cumulative dose to the primary sites was 59.4 gray (Gy), with single doses of 1.8 Gy. A total of 45 Gy was delivered to the neck area. Finally, all patients were treated with recombinant IFN-beta (10(5) U per kg of body weight) 3 times a week for 6 months. RESULTS: The response rate was 91%. These patients stayed in first remission during a median follow-up of 32 months. With the exception of one reversible cardiotoxicity, moderate chemotherapy-related toxicity was observed. CONCLUSIONS: In this study, patients with advanced stage NPC had a good prognosis with treatment consisting of neoadjuvant cisplatin and 5-fluorouracil, radiotherapy, and adjuvant IFN-beta. It is particularly noteworthy that distant metastases did not develop.

Adenocarcinoma, Clear Cell↗
PubMed1997

P300 from a single-stimulus paradigm: passive versus active tasks and stimulus modality.

The P300 component of the event-related brain potential (ERP) was elicited with auditory and visual stimuli in separate experiments. Each study compared an oddball paradigm that presented both target and standard stimuli with a single-stimulus paradigm that presented a target but no standard stimuli. Subjects were instructed in different conditions either to ignore the stimuli, press a response key to the target, or maintain a mental count of the targets. For the passive ignore conditions, P300 amplitude from the single-stimulus paradigm was larger than that from the oddball paradigm. For the active tasks, P300 amplitude from the oddball paradigm was larger than that from the single-stimulus paradigm. For the press and count conditions, P300 amplitude and latency were highly similar for the oddball and single-stimulus procedures. The findings suggest that the single-stimulus paradigm can provide reliable cognitive measures in clinical/applied testing for both passive and active response conditions.

Acoustic Stimulation↗
PubMed1997

[Lower extremity salvage in diabetics: microsurgical muscle transplantation with and without previous vascular reconstruction].

Soft tissues wounds with or without bony involvement are a common problem and a cause of limb loss in diabetics. Usually local care, antibiotics, minor debridement and skin grafting are enough for successful handling of these lesions. When there is associated limb ischemia, revascularization is indicated. In patients with large ulcers, proximal bony involvement and tendon exposure, the incidence of primary amputation rises, frequently being considered the only alternative. Two cases of diabetic patients with indication of primary amputation of a lower limb for large infected ulcers are reported. A microvascularized muscle transplant was used to cover large defects of soft tissue, tendons and infected bone. One patient presented also critical ischaemia of the limb, requiring iliac angioplasty and a femoro-distal by-pass with in situ greater saphenous vein previous to the muscle graft. Both patients had no postoperative complications, being able to walk two months after the operation with their useful limb. Microvascularized muscle transplant with or without revascularization is a very useful alternative to amputation in the management of complex wounds of selected diabetic patients.

Adult↗
PubMed1997

[Abdominal aortic aneurysm: course of morbimortality of elective surgery in 20 years].

Abdominal aortic aneurysms (AAA) usually undergo progressive dilatation and eventually may rupture, complication that carries a high mortality rate. If certain clinical conditions, like operative risk and aortic diameter are met, all patients should be considered for surgical repair. Analysis of our results with the surgical treatment of asymptomatic AAA prompted this study. Out of 479 consecutive patients operated because of AAA between 1976 and 1995, 378 (79%) were electively treated. Two decades: 1976-85 (101 patients) and 1986-95 (277 patients) were compared as far as associated medical conditions, surgical procedures, complications and mortality rate. There was no difference in age, sex, risk factors and aortic diameter. During the second decade we favoured the use of aortic tube grafts (53% vs 25%, p < 0.01) and epidural anesthesia (94% vs 35%, p < 0.01). During the last decade only 53.3% of the patients received blood transfusion, compared to 95.3% during the first period (p < 0.001). Operative mortality decreased from 5.94% to 0.72% (p < 0.05). Postoperative hospital stay diminished from 11.2 +/- 8.2 to 9.6 +/- 6.3 days (p < 0.05). These results compare favourably with those reported from other academic centers and support our therapeutic approach. Our contemporary surgical results serve as a reference for future clinical evaluation of endovascular procedures currently under investigation.

Aged↗
PubMed1997

[Mycotic aneurysms and multiple peripheral embolisms in a patient with infectious endocarditis].

Sepsis from an infected cardiac valve can lead to bacterial seeding and destruction of the arterial wall with formation of a mycotic aneurysm. The natural history of these lesions is the rupture. We report the case of a 20 year old female who was admitted to our institution with massive mitral regurgitation and emboli of the central nervous system and both lower extremities. She underwent emergency valve replacement and then, staged treatment of her ischemic legs and multiple asymptomatic mycotic aneurysms: Superior mesenteric, right common iliac and left superficial femoral arteries. A splenectomy was required to treat a splenic abscess. An aneurysm of a peripheral branch of the middle cerebral artery was medically treated, demonstrating reduction in size on subsequent angiogram. She recovered uneventfully and remains asymptomatic after 20 months of follow up. The development of new diagnostic and therapeutic tools has led to a decrease of these complications during infectious endocarditis. However, in the patient with late diagnosis and symptoms in different territories, the mycotic aneurysm must be kept in mind to provide the patient with appropriate treatment.

Abscess↗
PubMed1996

[Methods in surgical antibacterial prophylaxis in Belgium, 1992-1995].

Since 1992, the Belgian network for the surveillance of nosocomial infections runs a system of voluntary surveillance of surgical wound infections, including the perioperative antibiotic prophylaxis patterns. From 1992 to 1995, the global rate of prophylaxis was 71%, calculated on 44,728 interventions from 72 hospitals, but in 11.4% of operations for which prophylaxis is indicated, it was not given. On the other hand, prophylaxis was prescribed in 55.6% of operations where it was not indicated. At least 4 out of 10 courses were inappropriate with respect to indication, duration or day of administration. Fifteen percent of all courses exceeded 2 days (28% in genitourinary surgery, and 20% in abdominal surgery). In orthopedic surgery, recommended indications were not followed in 42% of operations. To improve the prescribing of antibiotic prophylaxis in Belgium, local surveillance of prophylaxis patterns and the implementation of guidelines describing good practices should be priorities at the hospital level. At the national level, recommendations about the indications for prophylaxis should be updated and disseminated.

Adult↗
PubMed1996

Methicillin-resistant Staphylococcus aureus epidemiology and control in Belgian hospitals, 1991 to 1995. Groupement pour le Dépistage, l'Etude et la Prévention des Infections Hospitalières.

OBJECTIVES: To describe the Belgian methicillin-resistant Staphylococcus aureus (MRSA) surveillance network, the evolution of methods used in Belgian hospitals for MRSA detection and control, and MRSA incidence from 1994 to 1995. DESIGN, SETTING, AND PARTICIPANTS: Questionnaire surveys; infection control physicians from acute-care hospitals in Belgium. INTERVENTION: Publication of national guidelines for MRSA control in 1993. RESULTS: The participation rate in surveys ranged from 42% to 57% of hospitals. In 1995, 88% of participants detected MRSA strains by disk diffusion tests, with little improvement in standardization since 1991. More centers employed the oxacillin agar screen method (27%), automated systems (29%), or a combination of methods (29%) than in 1991 (P < .005). Between 1991 and 1995, the proportion of hospitals reporting MRSA control measures increased from 68% to 95% (P < .01). Practices that were used increasingly included patient placement in private room (from 50% to 93%, P < .01) and hand decontamination with antiseptic (from 43% to 87%, P < .01). The proportion of centers that reported screening MRSA carriers and treating them topically increased two- and threefold, respectively (P < .05). Surveillance data from 1994 to 1995 showed that MRSA represented a mean of 21.3% of S aureus clinical isolates (range, 1.6% to 62.4%). The median incidence of nosocomial MRSA acquisition was 2.8 per 1,000 admissions, with a wide range (0 to 13.7 per 1,000 admissions) across hospitals of all sizes. The median incidence decreased over the first three semesters of surveillance in hospitals with continuous participation. CONCLUSION: MRSA detection and control measures have improved in Belgian hospitals after publication of national guidelines. However, MRSA incidence rates show the persistence of nosocomial transmission, with large variations between centers. The national MRSA surveillance network should indicate whether control efforts eventually will curb the problem.

Belgium↗
PubMed1996

Surgical wound infection surveillance: results from the Belgian hospital network.

Since October 1992, the Belgian National Programme for the Surveillance of Hospital Infections has been implemented successfully in more than two-thirds of all Belgian acute-care institutions. Practitioners from hospitals participating in the surgical wound infection surveillance describe a selection of surgical procedures, practices connected (antimicrobial prophylaxis), and record the eventual infection, enabling the calculation of wound infection rates. The network allows comparisons of each hospital results with the national picture. From October 1992 to June 1993, 16,799 procedures were recorded by 51 hospitals; the crude incidence rate of infection was 1.47 per 100 operations. However, this figure may be an underestimation of the reality because of potentially missed post-discharge infections. Risk factors significantly associated with infection include length of preoperative stay, emergency, duration of surgery, wound contamination class, and American Society of Anesthesiologists (ASA) score. The National Nosocomial Infections Surveillance system (NNIS) risk index, a combination of the three latter shows a good correlation for predicting infection. Increased length of stay attributable to the infection was computed at 8.9 days. Micro-organisms isolated reveal a staphylococcal predominance. Antibiotic prophylaxis prescription present satisfactory quality performances regarding duration and time of initiation but rational prescribing about the indications is still of concern.

Anti-Bacterial Agents↗
PubMed1996

Antimicrobial prophylaxis in surgery in Belgian hospitals: room for improvement.

OBJECTIVE: To evaluate the current practice of surgical antimicrobial prophylaxis in Belgium. DESIGN: Prospective multicentre incidence study. SETTING: 58 of the 206 acute hospitals in Belgium. SUBJECTS: 19746 patients who had operations between October 1992 and June 1993, with detailed analysis of 7983 procedures for which the antimicrobial regimens were known. RESULTS: Antibiotic prophylaxis was given before 14099 (71%) of the 19746 operations. It was given in 57% of the procedures for which prophylaxis is generally not recommended, but it was not used in 14% of procedures for which it is generally recommended, nor in 14% of all contaminated procedures. Duration of operation superseded degree of wound contamination, ASA (American Society of Anesthesiologists) score, and degree of urgency as a predictor of the use of prophylaxis. Prophylaxis was prolonged by more than 2 days postoperatively after 23% of the procedures and by more than 4 days in 8%. Five types of regimens accounted for 80% of all prophylaxis, but overall 234 different regimens were prescribed. Large differences were found in hospital university affiliation status. In general, trends were favourable compared with a study in 1986. CONCLUSION: Although there was improvement compared with 1986, antimicrobial prophylaxis in surgery could still be more appropriate in terms of indication, duration, and rational choice of drugs.

Antibiotic Prophylaxis↗
PubMed1996

[Metalloproteinase in carotid endarterectomy plaques: increased activity in critical stenosis zones].

BACKGROUND: The presence of metalloproteinases in atherosclerotic plaques has been described but their role is not well understood. An increased secretion of these proteolytic enzymes could explain plaque instability and distal embolization. AIM: To measure metalloproteinase activity in atherosclerotic plaques obtained after carotid endarterectomy. MATERIAL AND METHODS: Plaques were divided in one segment with and one segment without stenosis, the latter being used as control. Both segments were incubated in culture media for 48 h or were fixed for histology. The conditioned medium was studied using gelatin zimography and digital densitometry. Metalloproteinases were identified by their molecular weight, inhibition with EDTA or Western Blot. Standard histologic study and immunohistochemistry were done. RESULTS: In stenotic areas, metalloproteinase 9 (92kD) secretion was 260% higher than in regular plaques (191 and 73 Kilopixels/microgram protein respectively p < 0.02). The histological study of stenotic areas showed macrophage infiltration and neoformation of blood vessels. CONCLUSIONS: The increased secretion of cellular matrix degrading enzyme metalloproteinase 9 in stenotic areas of atherosclerotic plaques, could explain plaque instability and subsequent embolization.

Arteriosclerosis↗
PubMed1996

[Pulmonary thromboendarterectomy: a case of surgical treatment of chronic pulmonary thromboembolism under circulatory arrest with deep hypothermia].

Pulmonary thromboendarterectomy under circulatory arrest and deep hypothermia is presently a curative treatment for pulmonary hypertension secondary to chronic pulmonary artery thromboembolic occlusion, but is still not frequently performed around the world. We report here the first successful pulmonary thromboendarterectomy under circulatory arrest performed in Chile. The patient was a 37 year old white man, high school teacher, with a 5 months history of effort dyspnea and cough. Pulmonary hypertension secondary to chronic pulmonary thromboembolism was confirmed by angiography and echocardiography. The patient was operated on April 27, 1995. After the operation the patient had an immediate and maintained normalization of his pulmonary hemodynamics. He presented periods of delirium that postponed mechanical ventilation disconnection until the 7th postoperative day, after which he had an uneventful neurological recovery. Before hospital discharge a control angiography showed complete patency of the pulmonary artery system with no evidence of residual thrombi. Presently he is enjoying a normal life and back to his teaching activities.

Adult↗
PubMed1996

[Carotid endarterectomy combined with myocardial revascularization: report of 27 patients].

Atherosclerosis is a systemic disease that may involve more than one territory. Myocardial infarction can occur after carotid endarterectomy and stroke is a well documented morbidity of coronary artery bypass grafting. To optimize results, we have performed concomitant carotid endarterectomy and myocardial revascularization in selected cases, with severe disease in both territories. During a 13-year period, 27 patients were submitted for this procedure, 21 (77.8%) were male and the average age was 67.6 years (range 59-81). All patients had high-grade internal carotid artery stenosis, five (18.5%) were symptomatic. Coronary artery disease symptoms were: unstable angina in 12 patients (44.4%) and effort angina in 15 (55.6%). Two patients (7.4%) required reintervention for postoperative bleeding. Two cases (7.4%) had transient renal dysfunction. One patient, with multiple organ failure, died on the 16th postoperative day (3.7%). Follow up was obtained in 26 patients (96.3%). Survival at 5 years was 80.6%, 95.7% of those patients were free of any neurologic symptom. Combined carotid and coronary surgery is a safe treatment option for atherosclerosis of multiple territories in selected patients; long term benefits are also obtained.

Aged↗