PubMed Health⌕ Search

Biomedical subjects

D M Albrecht

Publications and source records attributed to D M Albrecht.

At least 19 recordsLinked to original sources
PubMed2004

[Reduction in the aggressiveness of ventilation by inhalation of perfluorohexane after therapy of oleic acid-induced respiratory failure].

INTRODUCTION: The application of perfluorohexane (PFH) vapor led to an improvement of oxygenation and mechanical lung function in a model of oleic acid-induced ARDS in sheep. The aim of this study was to investigate the effects of PFH on gas exchange over an extended time period and to reduce the invasiveness of ventilation. METHOD: ARDS was induced in sheep ( n=12) by injecting 0.1 ml/kg body weight oleic acid intravenously. Six sheep were treated for 30 min with 18 vol.% PFH (PFH-Tx) and followed up over a time period of 240 min while untreated sheep ( n=6) served as controls. Subsequently the F(I)O(2) was reduced to generate a p(a)O(2) between 100-140 mmHg. Gas exchange, respiratory and hemodynamic data were collected at regular intervals. Data were analysed using covariance analysis. RESULTS: PFH treatment led to an improvement in oxygenation ( p<0.01) and in mechanical lung function ( p<0.01). Furthermore, mean pulmonary artery pressure ( p<0.01) and shunt ( p<0.01) were lower in PFH-Tx. F(I)O(2) could be reduced in all PFH-treated animals ( p<0.01). CONCLUSION: Treatment of oleic acid-induced lung injury with PFH vapor improved oxygenation and mechanical lung function over a extended time period allowing a reduction in the invasiveness of ventilation.

Animals↗
PubMed2001

A comparison of five solutions of local anaesthetics and/or sufentanil for continuous, postoperative epidural analgesia after major urological surgery.

BACKGROUND AND OBJECTIVE: The aim of the present study was to compare and assess the quality of analgesia, the safety and the side-effects after the use of a continuous, thoracic epidural infusion of sufentanil (5 microg h(-1)), 0.25% bupivacaine (10 mL h(-1)), 0.2% ropivacaine (10 mL h(-1)) alone or in combination in patients who had undergone major urological surgery. This prospective, randomized, double-blinded study investigated the efficacy of thoracic epidural infusions after major urological surgery. METHODS: Patients received a 72-h continuous infusion (10 mL h(-1)) of 0.25% bupivacaine (B), 0.2% ropivacaine (R), 0.25% bupivacaine with 0.5 microg mL(-1) sufentanil (BS), 0.2% ropivacaine with 0.5 microg mL(-1) sufentanil (RS) or 0.5 microg mL(-1) sufentanil only (S). The analysis included 109 patients. RESULTS: The mean visual analogue scale (VAS) scores for pain were highest in the groups R and S (P < 0.001). The PaCO2 values were significantly higher in the groups RS and S (P = 0.003). Motor block occurred more frequently in the groups B and BS than in the other groups (P < 0.001). Sedation, nausea and pruritus were more common in the groups that received sufentanil. CONCLUSIONS: A continuous, epidural infusion with these drugs was safe and effective in our patients. The combination of 0.2% ropivacaine plus sufentanil appeared preferable because of the low incidence of motor block.

Aged↗
PubMed2001

Grand mal convulsion and plasma concentrations after intravascular injection of ropivacaine for axillary brachial plexus blockade.

We report a patient to whom ropivacaine 1.1 mg kg(-1) was administered for brachial plexus blockade and who developed grand mal convulsions because of inadvertent i.v. injection. No symptoms of cardiovascular toxicity occurred. Venous blood samples were taken 15, 45, 75 and 155 min after the injection. The measured total plasma concentrations of ropivacaine were 3.3, 1.6, 1.2 and 1.0 mg litre(-1) respectively. Initial plasma concentration after the end of the injection period was estimated at 5.75 mg litre(-1) using a two-compartment pharmacokinetic model.

Aged↗
PubMed2001

Perfluorohexane attenuates proinflammatory and procoagulatory response of activated monocytes and alveolar macrophages.

BACKGROUND: A number of studies have demonstrated the effectiveness of liquid ventilation with perfluorocarbons in improving pulmonary function in acute respiratory distress syndrome. Although it is known that perfluorocarbon-associated gas exchange facilitates lung mechanics and oxygenation, the complete mechanism by which perfluorocarbons exert their beneficial effects in acute lung injury still remains unclear. Possibly, an influence of perfluorocarbons on proinflammatory and procoagulant features of monocytic cells present in the alveolar space, such as alveolar macrophages (AMs), may be involved. Therefore, we examined in an in vitro model the effects of perfluorocarbon on both activated mononuclear blood cells (MBCs) and AMs by monitoring the expression of interleukin (IL)-1 beta, tumor necrosis factor (TNF)alpha, and tissue factor (TF). METHODS: Mononuclear blood cells, obtained from peripheral blood of healthy volunteers, or AMs from diagnostic bronchoalveolar lavage were stimulated by incubation with lipopolysaccharide in the presence of different amounts of perfluorohexane, which was devoid of cytotoxicity. RESULTS: Using both video-enhanced contrast and electron microscopy, the authors observed that perfluorohexane droplets were phagocytosed by activated monocytes as well as by in vitro--cultured AMs within 1--3 h. After lipopolysaccharide stimulation of monocytes or AMs, we observed a down-regulation of TF mRNA and a significant inhibition (P < 0.05) of cellular TF antigen by perfluorohexane. In addition, the concentration of both IL-1 beta and TNF alpha in the supernatant of lipopolysaccharide-stimulated MBC was significantly decreased (P < 0.01) by perfluorohexane compared with controls without perfluorohexane. By preincubation of lipopolysaccharide-containing medium with perfluorohexane, the authors could exclude that the inhibitory effect of perfluorohexane was caused by binding or sequestering limited amounts of lipopolysaccharide. CONCLUSION: Taken together, our results demonstrate an interference of perfluorohexane with the expression of the procoagulant protein TF on monocytes and AMs as well as with the release of proinflammatory cytokines by MBCs. These effects may contribute to the protective role of liquid ventilation with perfluorocarbons in injuries associated with local activation of inflammatory processes.

Enzyme-Linked Immunosorbent Assay↗
PubMed2001

Relationship of comorbidity, age and perioperative complications in patients undergoing radical prostatectomy.

OBJECTIVES: To investigate the prevalence and distribution of comorbidity and its association with perioperative complications in patients undergoing radical prostatectomy (RPE). METHODS: In 431 unselected RPE patients, the American Society of Anesthesiologists Physical Status classification (ASA-PS), the New York Heart Association classification of cardiac insufficiency (NYHA), the classification of angina pectoris of the Canadian Cardiovascular Society (CCS), height, weight, the body mass index (BMI), and the number of concomitant diseases (NCD) were assessed and related to perioperative cardiovascular complications. RESULTS: In RPE patients less than 70 years old, comorbidity rose nearly continuously with increasing age. However, after reaching an age of 70 years, the proportion of NYHA-0 patients increased (60-64 years, 86%; 65-69 years, 85%; >or=70 years, 87%). Furthermore, the severe comorbidities decreased in patients selected for RPE aged 70 or more years. There was a nonsignificant trend towards higher comorbidity in patients with perioperative cardiovascular complications. CONCLUSIONS: These data suggest that documentation of the distribution of ASA-PS, CCS, NYHA and of concomitant diseases might be helpful to characterize the general health status and the degree of selection of prostate cancer treatment populations especially in series with a high portion of patients aged 70 or more years. Concerning perioperative complications, the individual predictive value of comorbidity seems to be poor in the radical prostatectomy setting.

Age Factors↗
PubMed2001

An approach to quality management in anaesthesia: a focus on perioperative care and outcome.

Health care systems throughout the world are faced with continuously rising health care expenditure. In Germany, a fee per capita system will be introduced by 2003 to keep the budgets for hospital care within limits. As a result, numbers of hospital beds and hospitals will be cut in the coming years. On the other hand, more and more patients and health care providers are asking if they are really receiving an adequate value for their money in the treatment they receive. All this will have a strong impact on the anaesthesiologist's work and her/his perception of the different facets of quality. Quality has various aspects for the anaesthesiologist. The patient as a customer should not incur any detrimental effects after a surgical procedure, and is accompanied by the anaesthesiologist throughout the perioperative setting. The surgeon needs optimal conditions to perform a procedure. The hospital must balance equally costs and income; this requires optimal operating room utilization. Finally, health insurance companies and the government are responsible for covering the cost of treatment according to the quality of the care delivered. Quality assessment concerning structure, process and outcome has to take these demands into account. Continuous quality improvement in the spirit of Deming's 'plan-do-check-act cycle' has to be part of anaesthesiologist's everyday routine. In future, the traditional barriers between the specialities treating a patient will be disrupted when reimbursement for treatment is made according to quality and efficacy of treatment.

Anesthesia↗
PubMed2000

[From isoflurane to perfluorohexane? Perfluorocarbons--therapeutic strategies in acute lung failure].

The introduction of Perfluorochemicals into medicine and especially into the treatment of severe lung injury is a fascinating scientific task. Many recall the famous experiments from Clark et al. in 1966 when he demonstrated "liquidventilation with perfluorocarbons" in the mammal species for the first time. After this hallmark, perfluorocarbons were subsequently introduced in research of acute lung injury by the techniques of Total- and Partial-Liquid-Ventilation (TLV; PLV). Perfluorocarbons (saturated organofluorids) have unique chemical and physical properties which made them attractive substances for intraalveolar application. The strong C-F bindings in the perfluorocarbon molecules are responsible for their chemical stability, biochemical inertness, high capacity to dissolve respiratory gases, low surface tension and high vapor pressures. Furthermore, the high density of the PFC lead to radio-opacity and their distribution to dependent lung areas. The efficacy of PFC liquid, applied by TLV/PLV has been demonstrated in numerous animal studies using different models of acute lung injury. Currently, several mechanisms of action of perfluorocarbon fluids in acute lung injury are discussed: recruitment of atelectatic alveoli, prevention of endexpiratory collapse of alveoli ("liquid PEEP"), redistribution of perfusion, oxygen transport, surfactant like effects and decrease of inflammation. Since total liquid ventilation has been used only in experimental models of lung injury, partial liquid ventilation has been introduced successfully into clinical trials (phase I-II). However, the results of the first randomised, controlled study of PLV in 90 adult patients suffering from severe respiratory failure (ALI/ARDS) showed no differences between PLV and conventional treatment. Furthermore, the instillation of relatively large amounts of liquid into the lungs poses several technical challenges and may be associated with complications such as liquithoraces, pneumothoraces and hypoxia. Since mammal lungs are evolutionary specialised to gas exchange using atmospheric oxygen, the application of liquids, even if they transport respiratory gases very well is not physiologic. To overcome these unwanted side effects, we developed a technique of perfluorocarbon vaporisation in analogy to the application of inhalation anaesthetic agents. After resolving some technical issues, this application technique was used successfully in an animal model of acute lung injury. Vaporisation of perfluorohexane in a concentration of 18 Vol.% of inspired gas improved significantly oxygenation and lung compliance. Though these results are promising, mechanisms of action, dose-efficacy relation, surfactant-perfluorocarbon interaction or anti-inflammatory effects of vaporised perfluorohexane are still unclear. These questions need to be clarified before this technique can be applied clinically. However, the inhalation of vapor, a technique already familiar to anaesthesiologists should avoid risks of large amounts of fluids in the bronchoalveolar space. Furthermore, this technique can be administered by established anaesthetic equipment with the advantage of exact dosing, continuous monitoring, and demand application in a way near to clinical routine.

Anesthetics, Inhalation↗
PubMed2000

[Combined anesthesia with epidural catheter. A retrospective analysis of the perioperative course in patients ungoing radical prostatectomy] .

Patients requiring radical prostatectomy (rPE), including retroperitoneal lymphadenectomy are often aged and have coexisting cardiopulmonary diseases, increasing the risk of perioperative complications. The aim of the present study was to evaluate our perioperative anaesthesiologic regimen over the last five years, in terms of safety and patients comfort. Records of 433 patients who underwent rPE between 1994 and 1999 in our hospital were retrospectively reviewed. Patients were divided in those who received: 1. general anaesthesia (GA) alone, 2. a combination of lumbar epidural anaesthesia (LEA) + GA or, 3. thoracic epidural anaesthesia (TEA) + GA. General anaesthesia was performed as balanced anaesthesia, and epidural administered local anaesthetics were bupivacaine 0.25% or ropivacaine 0.2%, 8-12 ml/h. In terms of intra- and postoperative numbers of tachycardiac and hypertensive episodes, a reduced stress response was observed under epidural anaesthesia (EA). Moreover, the weaning duration was shorter under EA and onset of gastrointestinal motility was found earlier ([h] GA: 50.6 +/- 11.1/LEA: 39.3 +/- 13.6/TEA: 33.8 +/- 13.0). Furthermore, a trend to rarer phases of postoperative vomiting and a significant decrease of in hospital stay of about one day ([d] GA: 12.4 +/- 5.8/LEA: 11.1 +/- 3.1/TEA: 11.5 +/- 3.8) was observed. The duration of personnel binding in the OR did not differ significantly between GA and TEA ([min] GA: 222.9 +/- 43.5/LEA: 238.2 +/- 41.8/TEA: 227.0 +/- 46.2), but ICU stay was shortened under TEA. Besides this, TEA reduced the number of pathologic postoperative thorax-x-rays. Senso-motor blockades, decreases of SaO2 and cardiac complications were experienced more frequent under LEA as compared with TEA. Combination of GA and EA, especially TEA, appears to improve perioperative care of patients undergoing rPE, in terms of patients safety and comfort.

Anesthesia, Epidural↗