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H Brandes

Publications and source records attributed to H Brandes.

At least 19 recordsLinked to original sources
PubMed2004

Central venous catheters--the inability of 'intra-atrial ECG' to prove adequate positioning.

BACKGROUND: The classic increase in P wave size, known as 'P-atriale', is a widely accepted criterion for determination of proper positioning of central venous catheter tips. Recent transoesophageal echocardiography (TOE) studies did not confirm intra-atrial position despite advancing the central venous catheter further than indicated by ECG guidance. We postulate that the pericardial reflection rather than the entry into the right atrium corresponds to the ECG changes. In order to test our hypothesis we sought to determine the anatomical substrate for the electrical changes in an animal study. Subsequently, a modified version of the study was undertaken in man and is also reported. METHODS: In six juvenile pigs the left external jugular vein and right carotid artery were cannulated. A triple-lumen central venous catheter was positioned by ECG guidance using a Seldinger wire as an exploring electrode. The venous and arterial catheters were suture fixed 2 cm beyond the onset of an increase in P wave size. The corresponding anatomical catheter tip position was determined by open exploration of the vessels and the heart. Subsequently the catheter tip position (during advancement) of a pulmonary artery catheter and the corresponding electrical ECG changes were examined in 10 patients during open chest cardiac surgery. RESULTS: All catheters-arterial and venous, in animals and humans-revealed an increase in size of the P wave as well as the QRS complex. All venous catheters were positioned in the superior vena cava, beyond the pericardial reflection but outside the right atrium. All arterial catheters were positioned in the ascending aorta thus also beyond the pericardial reflection. CONCLUSIONS: The start of an increase in P wave size does not correspond with the entrance of the right atrium. The anatomic equivalent for the electrophysiological changes of the ECG is the pericardial reflection. ECG guidance is unable to distinguish between venous and arterial catheter position.

Aged↗
PubMed2003

Post-operative hypoalbuminaemia and procalcitonin elevation for prediction of outcome in cardiopulmonary bypass surgery.

BACKGROUND: Because few studies have addressed postoperative hypoalbuminaemia in relation to hospital mortality, we evaluated this association and the prognostic value of increased procalcitonin (PCT) after cardiopulmonary bypass (CPB) surgery. METHODS: In 454 consecutive patients undergoing CPB, minimal serum albumin, colloid osmotic pressure (COP) and maximal PCT were retrospectively obtained from the 2nd to 10th postoperative day. Receiver operating characteristic (ROC) and multiple regression analyses determined independent predictive strength for 28-day mortality from preoperative albumin, Euroscore, postoperative minimal albumin and COP, and maximal PCT. Cut-off points for the four strongest predictors were calculated by the area under the curve (AUC) in the ROC for the 28-day mortality. RESULTS: Maximal PCT showed the largest AUC (0.85; 95% CI 0.79-0.90) and the highest relative risk (RR 12.17; 95%CI 5.26-28.16; P < 0.001), compared with postoperative albumin (AUC 0.72; 95% CI 0.62-0.81; RR 5.35; 95%CI 2.99-9.56; P < 0.001) and EuroSCORE (AUC 0.73; 95%CI 0.63-0.83; RR 4.48; 95%CI: 1.78-11.28; P < 0.01). By logistic regression, postoperative albumin was the strongest predictor of mortality (odds ratio 0.86; 95% CI 0.84-0.89). Cut-off values for predicting 28-day mortality were found for postoperative albumin and PCT at 17.8 g l(-1) and 2.5 ng l(-1), respectively. A slight but significant inverse correlation between PCT and albumin was found. Patients with albumin less than the cut-off showed significantly higher median values for PCT levels (2.5 vs. 1.0 g l-1), a higher 28-day mortality rate (20.8% vs. 4.5%), and a longer ICU stay (6 vs. 3 days) in comparison with patients with minimal albumin greater than 18 g l(-1). CONCLUSIONS: Post-operative serum albumin <18 g l(-1) and PCT >2.5 ng l(-1) are predictive for a higher 28-day mortality rate in cardiosurgical patients. Both peak PCT and minimal albumin were better outcome predictors than the Euroscore, which better represents the preoperative condition of the patient.

Aged↗
PubMed2002

Redo- extirpation of a cardiac leiomyosarcoma to avoid transplantation.

Cardiac leiomyosarcoma is a very rare entity that is found in less than 0.2 % of all cardiac tumors. At the time of primary diagnosis, it often shows advanced local invasion or may even be metastasized. Thus, complete resection can not easily be achieved. Cardiac transplantation has been reported as a therapeutic option. Here, we report on a case of a leiomyosarcoma reoccurrence arising 2 years after initial surgery. We performed a radical redo-extirpation without the necessity of transplantation.

Adult↗
PubMed2001

Influence of high molecular dextrans on lung function in an ex vivo porcine lung model.

BACKGROUND: Extracellular preservation solutions utilizing high molecular agents can reduce intracellular edema during ischemia/reperfusion in lung transplantation. A solution of 40,000 dalton molecular weight (DMW) has already been clinically established (Perfadex). However, it is unclear whether dextrans of this particular size represent the optimal additive for lung preservation solutions. MATERIALS AND METHODS: In a new ex vivo porcine lung model, lungs were each preserved with low-potassium solutions containing 5% dextran with 90,000 DMW (Dex 90) and 160,000 DMW (Dex 160) and with Perfadex (40,000 DMW). After 24 h of cold ischemia, reperfusion was performed employing a roller pump with a pulsatile module. Lungs were perfused with deoxygenated perfusate and ventilated with room air. The oxygenation capacity (Delta pO(2)), peak inspiratory pressure (PIP), and mean pulmonary artery pressure (PAP) were monitored for 60 min. Net weight gain (NWG) and wet-to-dry ratio (W/D ratio) were determined. Free-radical generation was assessed by measuring malondialdehyde (MDA) at 10, 30, and 50 min. RESULTS: PIP and PAP increased in all groups significantly during reperfusion. However, Dex 160-perfused lungs exhibited significantly higher values than those with Dex 90 and Perfadex. Perfadex showed the highest Delta pO(2) throughout the entire reperfusion, while Delta pO(2) was slightly reduced in Dex 160 and significantly lower in Dex 90. In Perfadex the lowest water content was observed assessed by NWG and W/D ratio. The highest MDA values were observed in Dex 90, followed by Dex 160, while the lowest values were seen in Perfadex. CONCLUSIONS: Preservation of the lung with Perfadex exhibited superior postischemic function in contrast to preservation solutions containing dextrans with a higher molecular weight.

Animals↗
PubMed2000

Retrograde flush perfusion with low-potassium solutions for improvement of experimental pulmonary preservation.

BACKGROUND: Optimal preservation of post-ischemic organ function is a continuing challenge in clinical lung transplantation. Retrograde instillation of preservation solutions has the theoretic advantage of achieving homogeneous distribution in the lung because of perfusing both the pulmonary and the bronchial circulation. So far, we have seen no experimental studies that include stereologic analysis of intrapulmonary edema concerning the influence of retrograde preservation on post-ischemic lung function after preservation with Perfadex and Celsior. METHODS: In an extracorporeal rat model, we perfused 8 lungs, each, using either antegrade or retrograde perfusion technique with Celsior (CE(ant)/CE(ret)) and Perfadex (PER(ant)/PER(ret)). Results were compared with low-potassium Euro-Collins. Post-ischemic lungs were reventilated and reperfused mechanically. We continuously monitored relative oxygenation capacity (ROC), pulmonary artery pressure, flush time, and wet/dry ratio. Furthermore, we used stereologic means to evaluate edema formation. Statistics comprised different analysis of variance models. RESULTS: Relative oxygen capacity of CE(ant)-protected lungs was superior to that of PER(ant) preservation (p = 0.05). Use of PER(ret) resulted in significantly higher ROC as compared with PER(ant) (p < 0.001) and was comparable to results obtained with CE-preservation, which was not further improved with retrograde application. CONCLUSIONS: Celsior provides better lung preservation than does Perfadex when administered antegradely. Retrograde application of Perfadex results in significant functional improvement as compared with antegrade perfusion, which reaches the standard of Celsior-protected organs. Additional in vivo experiments in combination with ultrastructural analysis are warranted to further evaluate retrograde delivery of preservation solutions, which could be used in clinical lung transplantation to further optimize current results.

Animals↗
PubMed1997

Potassium-reduced lung preservation solutions: a screening study.

In recent years several potassium-reduced solutions have been developed for improvement of pulmonary preservation. A comparison of these solutions in a single study, however, has not yet been performed. In an extracorporeal working rat heart-lung model (n = 7/group) lungs were preserved with 20 ml Euro-Collins (EC), low potassium EC (LPEC), low potassium 2% dextran (LPD), ET-Kyoto (ETK) or low potassium 5% dextran (Perfadex) solution, while hearts were arrested with 10 ml St. Thomas' cardioplegia. Lungs of controls were not perfused. The heart-lung blocks were stored for 2 h at 10 degrees C. Thereafter, heart-lung blocks were extracorporeally perfused with Krebs-Henseleit solution with washed bovine red blood cells. Coronaries were perfused with oxygenated perfusate. Lungs were perfused via the working right ventricle with deoxygenated perfusate and ventilated with room air. Oxygenation capacity (dPO2) and pulmonary vascular resistance (PVR) were measured. Reperfusion/ventilation was performed for 40 min. At the end of the experiment the wet to dry (W/D) ratio of lungs and light microscopic assessment of the degree of edema (0-4) were performed. All potassium-reduced solutions showed superior dPO2 and a lower PVR than EC and controls while LPEC exhibited the most stable dPO2 and lowest PVR after 30 min reperfusion. The W/D ratio of all potassium-reduced groups was lower than the ratio of EC and controls. In LPEC, ETK and Perfadex the least degree of edema was noted. All solutions used in this study are superior to regular EC. However, when compared directly, LPEC perfused lungs showed better functional preservation than all other alternative solutions.

Animals↗
PubMed1996

Comparison of low potassium Euro-Collins solution and standard Euro-Collins solution in an extracorporeal rat heart-lung model.

OBJECTIVE: Euro-Collins solution (EC) is routinely used in lung transplantation. The high potassium of EC, however, may damage the vascular endothelium, thereby contributing to postischemic reperfusion injury. To assess the influence of the potassium concentration on lung preservation, we evaluated the effect of a "low potassium Euro-Collins solution" (LPEC), in which the sodium and potassium concentrations were reversed. METHODS: In an extracorporeal rat heart-lung model lungs were preserved with EC and LPEC. The heart-lung blocks (HLB) were perfused with Krebs-Henseleit solution containing washed bovine red blood cells and ventilated with room air. The lungs were perfused via the working right ventricle with deoxygenated perfusate. Oxygenation and pulmonary vascular resistance (PVR) were monitored. After baseline measurements, hearts were arrested with St. Thomas' solution and the lungs were perfused with EC or LPEC, or were not perfused (controls). The HLBs were stored for 5 min or 2 h ischemic time at 4 degrees C. Reperfusion and ventilation was performed for 40 min. At the end of the trial the wet/dry ratio of the lungs was calculated and light microscopic assessment of the degree of edema was performed. RESULTS: After 5 min of ischemia oxygenation was significantly better in both preserved groups compared to the controls. Pulmonary vascular resistance was elevated in all three groups after 30 min reperfusion at both ischemic times. After 2 h of ischemia PVR of the group preserved with LPEC was significantly lower than those of the EC and controls (LPEC-5 min: 184 +/- 65 dynes * sec * cm-5, EC-5 min: 275 +/- 119 dynes * sec * cm * cm-5, LPEC-2 h: 324 +/- 47 dynes * sec * m-5, EC-2 h: 507 +/- 83 dynes * sec * cm-5). Oxygenation after 2 h of ischemia and 30 min reperfusion was significantly better in the LPEC group compared to EC and controls (LPEC: 70 +/- 17 mmHg, EC: 44 +/- 3 mmHg). The wet/dry ratio was significantly lower in the two preserved groups compared to controls (LPEC-5 min: 5.7 +/- 0.7, EC-5 min: 5.8 +/- 1.2, controls-5 min: 7.5 +/- 1.8, LPEC-2 h: 6.7 +/- 0.4, EC: 6.9 +/- 0.4, controls-2 h: 7.3 +/- 0.4). CONCLUSIONS: We thus conclude that LPEC results in better oxygenation and lower PVR in this lung preservation model. A low potassium concentration in lung preservation solutions may help in reducing the incidence of early graft dysfunction following lung transplantation.

Animals↗
PubMed1995

Influence of red blood cells on lung function in an ex vivo rat heart-lung model.

Crystalloid perfusates commonly are utilized for lung preservation in extracorporeal small animal lung models. However, the function of these grafts is limited. In a new ex-vivo rat heart-lung model the role of red blood cells added to the crystalloid perfusate was investigated. Heart-lung blocks were rapidly excised (n = 9, each group) and the blocks were connected to the extracorporeal perfusion circuit using Krebs-Henseleit solution (KH) or KH with washed bovine red blood cells (hematocrit 38%) (KHRBC). The lungs were ventilated with room air. The coronary system was perfused via the aortic root with oxygenated perfusate. The lungs were perfused via the right ventricle with deoxygenated perfusate (PO2 15 mm Hg). Venoarterial improvement of oxygenation, pulmonary vascular resistance (PVR), and peak inspiratory pressure (PIP) were continuously monitored for 50 min. At the end of the experiment the wet/dry (W/D) ratio was determined using the mediastinal lung lobe while the remaining lung was used for light microscopic (LM) evaluation. After 30 min of perfusion, lung function was significantly better in the KHRBC group (PVR (KH): 752 +/- 193 dyn*sec*cm-5; (KHRBC): 279 +/- 48 dyn*sec*cm-5; PIP (KH): 31 +/- 3.2 mm Hg; (KHRBC): 25.8 +/- 1.9 mm Hg). In addition, lungs perfused with KHRBC showed significantly less edema than those perfused with KH only (W/D ratio (KH): 7.8 +/- 1.2; (KHRBC) 5.1 +/- 0.6; LM (KH): 3.5 +/- 0.9; (KHRBC): 2.3 +/- 0.8). The use of red blood cells in KH perfusate improved functional and structural integrity.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

[Imaging procedures in preoperative lymph node staging of invasive bladder cancer. Necessary or superfluous?].

A staging programme for detection of lymph node involvement before radical cystectomy has been carried out in 22 patients. The programme includes: intravenous pyelography, chest X-ray, abdominal sonography, bone scan, CT and MRI. Also an immunoscintigraphic examination using monoclonal anti-CEA antibody (TUMAK BW 421/26) was done in every patient. Preoperative lymph node staging using CT, MRI and immunoscintigraphy was compared with post-operative histological staging: a total of 5 patients were found to have lymph node involvement. In none of them had lymph node involvement been predicted on the basis of CT, MRI or immunoscintigraphy.

Aged↗
PubMed1975

[Extranuclear sites of action in UV-irradiated Fumaria hygrometrica (author's transl)].

Isolated filaments of Funaria hygrometrica have been treated by whole-cell UV irradiation (265 nm) as well as by microirradiation of the nucleus. 4 to 5 hrs thereafter the cells showed a depression in length growth. The intensity of this depression remarkably depends on the absorbed energy only. It does not matter whether the nucleus and its environcence or the whole cell are irradiated. The effect does not show photoreactivation and is rather independent from the cell cycle and hence from the DNA content of the nucleus. After X-irradiation supplying the same amount of absorbed energy no damage is detectable. The authors conclude that the site of the primary radiation effect is situated mainly outside the nucleus and that it may be a damage of the m-RNA, r-RNA or of membranes.

Cell Division↗
PubMed1969

Studies on the distribution and properties of a new class of cell division--promoting substances from higher plant species.

One member of a new class of cell division-promoting substances, which are nicotinamide derivatives, has been found to be present in dividing cells of tobacco and cactus. These plants are taxonomically far removed from one another and from Vinca rosea L., the plant species from which the new substances were first isolated. Because of their apparent wide distribution among dicotyledonous plant species, the question is raised as to whether the nicotinamide derivatives rather than the purine cytokinins may not, in fact, be the naturally occurring cell division factors that are directly involved in promoting cytokinesis in higher plant species. Unequivocal evidence is presented to show that the nicotinamide derivatives do not owe their biological activity to contamination by 6-substituted purine cytokinins.

Cell Division↗
PubMed1968

Studies on cytokinin-controlled bud formation in moss protonemata.

Application of cytokinins to moss protonemata of the proper physiological age causes bud formation on specific cells (caulonema). During the early stages of their development, buds revert to protonemal filaments if the cytokinin has been removed by washing the protonemata. This indicates that the hormone is not acting as a "trigger" but has to be present during a critical period of time until differentiation is stabilized. Autoradiographs of protonemata treated with a labeled cytokinin, benzyladenine-benzyl-7-(14)C, show a striking accumulation of the radioactivity in caulonema cells which are in the stage of bud formation, and in the buds themselves. Cells which did not react to the hormone contained very little radioactivity. The accumulation of benzyladenine in the "target cells" may be due to the presence of binding sites which, in turn, may distinguish responding cells from non-responding ones.

Journal Article↗