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H Wulf

Publications and source records attributed to H Wulf.

At least 19 recordsLinked to original sources
PubMed2006

Microglia and macrophages express tumor necrosis factor receptor p75 following middle cerebral artery occlusion in mice.

The proinflammatory and potential neurotoxic cytokine tumor necrosis factor (TNF) is produced by activated CNS resident microglia and infiltrating blood-borne macrophages in infarct and peri-infarct areas following induction of focal cerebral ischemia. Here, we investigated the expression of the TNF receptors, TNF-p55R and TNF-p75R, from 1 to 10 days following permanent occlusion of the middle cerebral artery in mice. Using quantitative polymerase chain reaction (PCR), we observed that the relative level of TNF-p55R mRNA was significantly increased at 1-2 days and TNF-p75R mRNA was significantly increased at 1-10 days following arterial occlusion, reaching peak values at 5 days, when microglial-macrophage CD11b mRNA expression was also increased. In comparison, the relative level of TNF mRNA was significantly increased from 1 to 5 days, with peak levels 1 day after arterial occlusion. In situ hybridization revealed mRNA expression of both receptors in predominantly microglial- and macrophage-like cells in the peri-infarct and subsequently in the infarct, and being most marked from 1 to 5 days. Using green fluorescent protein-bone marrow chimeric mice, we confirmed that TNF-p75R was expressed in resident microglia and blood-borne macrophages located in the peri-infarct and infarct 1 and 5 days after arterial occlusion, which was supported by Western blotting. The data show that increased expression of the TNF-p75 receptor following induction of focal cerebral ischemia in mice can be attributed to expression in activated microglial cells and blood-borne macrophages.

Animals↗
PubMed2006

Risk factors for prilocaine-induced methaemoglobinaemia following peripheral regional anaesthesia.

BACKGROUND: The local anaesthetic prilocaine has a low systemic toxicity mainly because of a high absorption in the lung and a large volume of distribution and thus is associated with a lower risk of neurological or cardiac side-effects. However, the major disadvantage is the formation of methaemoglobin by its metabolite o-toluidine. This prospective observational study was performed to identify factors that are associated with increased prilocaine-induced methaemoglobinaemia. PATIENTS AND METHODS: One Hundred and sixty two patients undergoing major knee surgery under general anaesthesia combined with peripheral nerve blocks (femoral nerve block, combined femoral/sciatic nerve block or lumbar plexus block) received a single bolus injection of 300 or 400 mg prilocaine about 30 min before surgery via a catheter. The proper placement was verified using nerve stimulation via a stimulating catheter. Three hours after prilocaine injection, venous blood samples were drawn and methaemoglobin levels were measured by standard photometric technique. Data was subjected to a stepwise multiple regression analysis. RESULTS: The mean methaemoglobin for all patients was 2.7% (range: 0.9-15.4%). A higher dose of prilocaine and younger age were the most important predictive factors for higher methaemoglobin formation. Female sex and to a lesser extent the use of high-concentration/low-volume prilocaine also increased methaemoglobin levels. These four factors of the model explain 36% of the total variance. Other investigated factors, including the patient's height, weight, body mass index, the site of catheter insertion, the anaesthetist's judgement concerning the difficulty of catheter placement, duration of catheter placement or an inadvertent puncture of a venous or arterial vessel, had no significant impact on the concentration of methaemoglobin. CONCLUSION: The use of prilocaine for regional block is safe, since the older patients who might be more susceptible to suffer from clinical symptoms of methaemoglobinaemia usually form less methaemoglobin. However, since prediction of high methaemoglobin levels is difficult, anaesthesiologists performing regional blocks in patients who might be jeopardized by a decreased oxygen transport capacity should avoid high doses of prilocaine.

Adolescent↗
PubMed2006

Relative contribution of matrix metalloprotease and cysteine protease activities to cytokine-stimulated articular cartilage degradation.

OBJECTIVE: Both matrix metalloprotease (MMP) activity and cathepsin K (CK) activity have been implicated in cartilage turnover. We investigated the relative contribution of MMP activity and CK activity in cartilage degradation using ex vivo and in vivo models. METHODS: Bovine articular cartilage explants were stimulated with oncostatin M (OSM) 10 ng/ml and tumor necrosis factor-alpha (TNF-alpha) 20 ng/ml in the presence or absence of the broad-spectrum MMP inhibitor GM6001 and the cysteine protease inhibitor, E64. Cartilage degradation was evaluated in the conditioned medium by glycosaminoglycans (GAG), hydroxyproline, and cross-linked C-telopeptide fragments of type II collagen (CTX-II), which were compared to immunohistochemical evaluations of proteoglycans and CTX-II. We assessed MMP expression by gelatine zymography and CK expression by immunohistochemistry. In vivo, CTX-II release was measured from CK-deficient mice. RESULTS: OSM and TNF-alpha combined induced significant (P<0.01) increase in cartilage degradation products measured by hydroxyproline and CTX-II compared to vehicle control. The cytokines potently induced MMP expression, assessed by zymography, and CK expression investigated by immunohistochemistry. Inhibition of MMP activity completely abrogated hydroxyproline and CTX-II release (P<0.01) and GAG release (P<0.05). In contrast, E64 resulted in increased CTX-II release by 100% (P<0.05) and inhibited GAG release by 30%. Up-regulation of CTX-II fragments was confirmed in vivo in CK null mice. CONCLUSION: Inhibition of MMP activity reduced both proteoglycan loss and type II collagen degradation. In contrast, inhibition of cysteine proteases resulted in an increase rather than a decrease in MMP derived fragments of collagen type II degradation, CTX-II, suggesting altered collagen metabolism.

Animals↗
PubMed2006

Calcitonin directly attenuates collagen type II degradation by inhibition of matrix metalloproteinase expression and activity in articular chondrocytes.

OBJECTIVE: Calcitonin was recently reported to counter progression of cartilage degradation in an experimental model of osteoarthritis, and the effects were primarily suggested to be mediated by inhibition of subchondral bone resorption. We investigated direct effects of calcitonin on chondrocytes by assessing expression of the receptor and pharmacological effects on collagen type II degradation under ex vivo and in vivo conditions. METHODS: Localization of the calcitonin receptor on articular chondrocytes was investigated by immunohistochemistry, and the expression by reverse transcriptase polymerase chain reaction (RT-PCR). In bovine articular cartilage explants, cartilage degradation was investigated by release of C-terminal telopeptides of collagen type II (CTX-II), induced by tumor necrosis factor-alpha (TNF-alpha) [20 ng/ml] and oncostatin M (OSM) [10 ng/ml], with salmon calcitonin [0.0001-1 microM]. In vivo, cartilage degradation was investigated in ovariectomized (OVX) rats administered with oral calcitonin [2 mg/kg calcitonin] for 9 weeks. RESULTS: The calcitonin receptor was identified in articular chondrocytes by immunohistochemistry and RT-PCR. Calcitonin concentration-dependently increased cAMP levels in isolated chondrocytes. Explants cultured with TNF-alpha and OSM showed a 100-fold increase in CTX-II release compared to vehicle-treated controls (P<0.001). The degradation of type II collagen in these explants was concentration-dependently inhibited by calcitonin, 65% protection at 10 nM calcitonin (P<0.01). TNF-alpha and OSM induced a pronounced increase in matrix metalloproteinase (MMP) activity, which was strongly inhibited by calcitonin. In vivo, administration of salmon calcitonin to OVX rats resulted in significant (P<0.001) decrease in CTX-II levels. CONCLUSION: These results are the first evidence of calcitonin receptor expression on articular chondrocytes and that the chondroprotective effects of calcitonin might involve the inhibition of MMP expression.

Animals↗
PubMed2006

[Use of the size 3 ProSeal laryngeal mask airway in children. Results of a randomized crossover investigation with the Classic laryngeal mask airway].

BACKGROUND: The low-pressure airway seal of the Classic laryngeal mask airway (CLMA) can be inadequate for positive pressure ventilation (PPV) in children. The ProSeal laryngeal mask airway (PLMA) forms a more effective seal of the airway than the CLMA and facilitates gastric tube placement in adults. The size 3 PLMA can be used in adults and children. METHODS: The CLMA and PLMA were studied in random order -- crossover -- in 30 anaesthetized, non-paralysed children (average age 10.6 years, average body weight 39 kg). Airway leak pressure, maximum tidal volume, ease of insertion, quality of initial airway and fiberoptic position were determined. Gastric tube placement was assessed for the PLMA. RESULTS: The mean airway leak pressure in neutral head position (27.0 vs. 16.8 cm H(2)O), maximum flexion (38.3 vs. 26.2 cm H(2)O) and maximum extension (21.1 vs. 14.2 cm H(2)O) as well as the mean maximum tidal volume (1432 vs. 1062 ml) were significantly higher (p<0.001) for the PLMA. Air insufflation into the stomach occurred with the CLMA but not with the PLMA. Gastric tube placement was possible in all patients. CONCLUSIONS: The high reliability of g-tube placement and the significantly increased airway leak pressure seem to make the size 3 PLMA a more suitable device for PPV in children than the same size CLMA.

Adolescent↗
PubMed2006

[Video laryngoscopy for modified rapid sequence induction of anaesthesia: Sellick manoever with and without video laryngoscopic control].

BACKGROUND: There is evidence that cricoid pressure, one of the key elements of rapid sequence induction (RSI) in patients at risk of aspiration, can distort the glottic view obtained by direct laryngoscopy (DL) and consequently impair or delay endotracheal intubation (ETI). The fact that cricoid pressure is applied by an assistant "blindly", i.e. without any visual feedback, is believed to be a contributing factor. Video laryngoscopy (VIL) offers the advantage that both the anaesthetist and the assistant can follow laryngoscopy. This could be useful for ETI during RSI. METHODS: We used VIL for a simulated RSI in 170 adult patients randomised to either video laryngoscopy-guided application of cricoid pressure (group I) or conventional, i.e. "blind", application of cricoid pressure (group II). Time to ETI was compared between groups. The laryngoscopy view obtained by VIL was compared with the view of conventional DL obtained before, in all patients. RESULTS: Time to ETI did not differ between groups (p=0.2): 25.1+/-14.2 s (group I) vs. 23.7+/-12.1 s (group II). Laryngoscopy scores were significantly better for VIL than conventional DL (p<0.001). CONCLUSIONS: Visualisation of the larynx during RSI can be improved using VIL. Time to ETI is not decreased by use of video laryngoscopy-guided application of cricoid pressure.

Adolescent↗
PubMed2006

[Loss of vision after non-ophthalmic surgery: systematic review of the literature on incidence, pathogenesis, treatment and prevention].

BACKGROUND AND GOAL: Postoperative loss of vision is a rare, but devastating complication after non-ocular surgery. It can occur partially or completely and may involve one or both eyes. Since its etiology has not yet been solved, the purpose of this review was to extract potential causes from the case collections reported to propose prophylactic measures. METHODS: A literature search was performed using the "Pubmed" database of the US National Library of Medicine. MeSH terms and combinations used were: blindness, postoperative complications, ischemic optic neuropathy, not ophthalmological surgical procedures, not neurosurgical procedures. Additionally, the results of the interim analysis of the postoperative visual loss (POVL) registry of the ASA were considered. RESULTS: The incidence of permanent loss of vision after non-ophthalmologic surgery is reported to be 0.0008%. However, it is elevated up to 0.11% after cardiac and 0.08% after spine surgery. Risk factors seem to be perioperative anemia, arterial hypotension and prone position, but also pre-existing diseases such as arteriosclerosis. Thus hemodynamic stabilization or correction of anemia may be successful in therapy. CONCLUSION: Patients with pre-existing arteriosclerotic disease scheduled for spine or cardiac surgery, but also for bilateral neck dissection should be informed preoperatively about the rare possibility of POVL. Postoperatively any visual changes should be immediately referred to an ophthalmologist and treated accordingly.

Atherosclerosis↗
PubMed2006

[Current level of patients' knowledge of anaesthesiology].

The anaesthesiologist's competence in anaesthesia, intensive care medicine, pain therapy and emergency medicine is accepted throughout the medical society. Nevertheless, during the last decades patient surveys demonstrated a considerable lack of information of the responsibility of our work. By continuous education and information anaesthesiologists have aimed to improve the information and decision-making process for the patient. This multicentre trial was designed to investigate the current public view on our profession in seven German hospitals. In-hospital patients were asked to fill out a standardised questionnaire prior to the anaesthesia premedication visit and a total of 692 questionnaires (77%) were analysed. Results demonstrated an increased level of knowledge for anaesthesia (>95%), intensive care medicine (74%), and pain therapy (50% acute pain; 32% severe pain). In the case of emergency medicine (10%) the in-hospital and out-of-hospital responsibilities were not clear among patients. We conclude that the continuous distribution of information in recent years has contributed to improving patients' knowledge on interdisciplinary responsibilities. Future efforts should focus on the gaps in patient's knowledge to allow the patient to ask the right questions necessary for decision-making.

Adult↗
PubMed2006

[Influence of neuromuscular blockade on the airway leak pressure of the ProSeal laryngeal mask airway].

BACKGROUND: The ProSeal laryngeal mask airway (PLMA) is increasingly used for surgical procedures that might require the intraoperative use of neuromuscular blocking agents. The airway seal of the PLMA depends on the interplay of the surrounding soft tissue of the neck and the cuff of the mask. An intraoperative neuromuscular blockade could lead to a decrease of the airway leak pressure (P (leak)) secondary to the relaxation of the muscles of the neck. With this study we tested the hypothesis that a neuromuscular blockade can result in a decreased P (leak) of the PLMA. METHODS: The P (leak) of the PLMA was studied in 73 female patients under total intravenous anaesthesia with propofol (0.1 - 0.15 mg kg (-1) min (-1)) and remifentanil (0.1 - 0.3 microg kg (-1) min (-1)) before and after a complete neuromuscular blockade produced by intravenous injection of 0.6 mg kg (-1) Rocuronium. RESULTS: The P (leak) decreased by more than 10 % of the baseline P (leak) in 8 out of 73 patients (11 %); however, in the entire study population there was no significant difference between the mean baseline P (leak) (28.5 +/- 7.3 cm H(2)O) and the mean P (leak) after complete neuromuscular blockade (29.1 +/- 7.0 cm H(2)O); (p = 0.128). CONCLUSION: No general correlation between application of a neuromuscular blocking agent and a decrease of the mean P (leak) was found. However, the decrease of the P (leak) by more than 10 % in 11 % of the patients shows that in certain patients the application of neuromuscular blocking agents can result in a decreased P (leak) of the PLMA and indicates the necessity to control the P (leak) of the PLMA under complete muscle paralysis preoperatively when neuromuscular blocking agents are used.

Adult↗
PubMed2006

Use of the LMA-ProSeal in an experimental pig model -- a potential animal model for laryngeal mask airway research: results of a pilot study.

OBJECTIVE: In light of the increased use of the LMA-ProSeal (P-LMA) it seems desirable to consider the P-LMA for prolonged surgical cases or post-operative ventilation. Long-term use could carry the risk of serious complications. An experimental pig model could be used to gain basic knowledge about long-term use before conducting clinical trails. In this randomized controlled study we tested the hypothesis if prolonged positive pressure ventilation (PPV) with the P-LMA in the pig is possible. METHODS: The P-LMA was used for airway maintenance under general anaesthesia and PPV in 15 German country pigs. Randomised into 3 groups, the animals were ventilated for 90, 150 and 390 minutes, respectively. Arterial blood gas measurements were used to determine adequacy of ventilation. Airway leak pressure (P (leak)) and maximum tidal volume (TV) were measured in the supine, lateral and prone positions. A bronchoscopic examination was performed to detect signs of aspiration. RESULTS: Adequate ventilation was demonstrated both after 120 min (4.7 +/- 0.4 kPa) and 360 min (4.7 +/- 0.5 kPa). The corresponding PaO(2) at FiO(2) = 1.0 was 59 +/- 5 kPa and 64 +/- 10 kPa, respectively. The mean P (leak) was 34 +/- 7 cm H(2)O. Change of position did not result in any significant change in P(leak) or maximum TV kg (-1). There was no bronchoscopic evidence of aspiration in any pig. CONCLUSION: It was possible to ensure sufficient PPV with the P-LMA in the pig over different periods of time and in different body positions without any complications of airway management. The P-LMA can be used for PPV in the pig for durations of up to 390 minutes. We conclude that investigations into the long-term use of the LMA can be carried out in a pig model.

Anesthesia↗
PubMed2006

[Anaesthesia education at german university hospitals: the teachers' perspective -- results of a nationwide survey].

AIM OF THIS STUDY: The principle purpose of this study was to collect data on the conditions and practice of anaesthesia education as well as the teaching qualification of consultants at German university hospitals. Based upon the collected data, areas of weakness and strength as well as measures required to improve anaesthesia training are described. METHODS: A questionnaire containing 26 items was mailed to 607 consultants employed at 41 German university hospitals in June 2003. RESULTS: A total of 255 questionnaires was analysed (response rate: 43 %). Genuine training activities account for 14 % of the working hours of the participating consultants. On average, at the institutions of participating consultants, novices work for a duration of 1 month together with a consultant anaesthetist before they give anaesthetics without direct and constant supervision. When asked to describe the predominant method of training at their institution 71 % indicated "case-oriented teaching"; however, 53 % chose "see one, do one, teach one" and 49 % "learning by doing" as method of training as well (multiple choice). According to 63 % of respondents, departmental educational activities usually happen after their regular working hours. "Daily workload" (96 %), "time pressure" (96 %), "lack of time" (96 %) and "lack of personnel" (90 %) were indicated as the main obstacles of teaching. According to 80 % of respondents, a dedicated financial budget for education does not exist; instead, financial resources of third parties (industry) (58 %), of the state (for research und undergraduate education) (60 %) and of patients service (66 %) are used to ensure training of anaesthesia residents. CONCLUSION: Due to a lack of a dedicated financial budget for resident training and an increasing economic pressure, "lack of time" and "lack of personnel" are the main factors leading to the situation at German university hospitals that consultants can only spend 14 % of their working hours for teaching purposes despite of sufficient qualification and motivation. As a consequence, novice anaesthetists are faced with the situation to be working without direct and constant supervision after 1 month of training.

Anesthesiology↗
PubMed2006

Anti-emetic prophylaxis with oral tropisetron and/or dexamethasone.

BACKGROUND: The corticosteroid dexamethasone and the serotonine3 -antagonist tropisetron are both effective drugs for the prophylaxis of post-operative nausea and vomiting (PONV) when given intravenously. The aim of this trial was to evaluate the oral use of both drugs as part of a routine oral premedication and to compare their single and combined effectiveness. MATERIALS AND METHODS: In this randomized, placebo-controlled, double-blind study, 320 inpatients with a moderate-high risk of PONV (> or = 40% according to two validated risk scores) received an oral premedication 1-2 h pre-operatively with placebo, a fixed dose of tropisetron 5 mg, dexamethasone 8 mg, or a combination of both drugs. A standardized general anaesthesia was performed, including benzodiazepine premedication, propofol, rocuronium, desflurane in air/O2, fentanyl or sufentanil followed by a continuous infusion of remifentanil. Post-operative analgesia and anti-emetic rescue medication were standardized. The main outcome measures were the severity of PONV within the first 24 h (rated by a standardized scoring algorithm). The incidence of PONV was used as the secondary outcome. RESULTS: Data from 310 patients were analyzed. The mean severity score in the placebo-, tropisetron-, dexamethasone- and the combined-groups was 1.37, 0.8, 0.8 and 0.38, respectively. The incidence of PONV of any severity was 59.2%, 37.5%, 40% and 22.8%, respectively. The reduction of the incidence and the severity of PONV were statistically significant with all three interventions. Results from additional analyses suggested that both drugs were equally effective and that there was a simple additive effect of tropisetron and dexamethasone compared with placebo. CONCLUSION: Oral tropisetron and dexamethasone were both equally effective in reducing the severity and incidence of post-operative nausea and vomiting. The latter could be reduced by approximately 35% in a population of moderate-high risk for PONV. Both drugs had an additive effect. However, even in the combination group there still remained an unacceptably high incidence of PONV of more than 20%. This highlighted the need for a multimodal anti-emetic approach in high-risk patients and the importance of treatment of PONV.

Administration, Oral↗
PubMed2005

Use of the ProSeal laryngeal mask airway for pressure-controlled ventilation with and without positive end-expiratory pressure in paediatric patients: a randomized, controlled study.

BACKGROUND: Tracheal intubation and positive end-expiratory pressure (PEEP) are frequently used in children to avoid airway closure and atelectasis during general anaesthesia. Also, the laryngeal mask airway (LMA(dagger)) is frequently used. However, one of the limitations with its use in children is that its low-pressure seal is often inadequate for positive pressure ventilation with PEEP. The ProSeal LMA (PLMA) has been shown to form a more effective seal than the Classic LMA. The ability to apply PEEP with the PLMA might improve gas exchange during positive pressure ventilation in children when the LMA is used. METHODS: Twenty anaesthetized, non-paralysed children aged 55 (range 27-89) months, weighing 18 (sd 3) kg, were randomly allocated into two groups. Anaesthesia management and positive pressure ventilation were standardized. Size 2 and 2(1/2) PLMA were used. Artificial ventilation in Group I was with pressure controlled ventilation (PCV) and PEEP=5 cm H(2)O, in Group II with PCV without PEEP. A Fi(o(2)) = 1.0 was used for 20 min during induction of anaesthesia. Sixty minutes after induction of anaesthesia an arterial blood gas sample was taken under a Fi(o(2)) = 0.3. RESULTS: Groups were comparable with respect to demographic data. Pa(o(2)) in Group I [22.1 (1.6) kPa] was significantly (P=0.001) higher than in Group II [19.2 (1.7) kPa]. CONCLUSIONS: The PLMA can be used for PCV with PEEP in paediatric patients. Application of PEEP improves gas exchange.

Anesthesia, General↗
PubMed2005

[Tattoos].

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Adult↗
PubMed2005

[Anesthesiological management of the EXIT procedure. Case report and literature review].

The ex-utero intra-partum (EXIT) procedure enables the surgeon to perform invasive procedures in an infant during cesarean section before clamping the umbilical cord. Specific anesthesiological concepts are necessary for ensuring sufficient umbilical perfusion. We report the case of a 33-year-old female undergoing cesarean section in the 36th week of pregnancy because of a large fetal cervical tumor. The EXIT procedure was performed in order to secure the infant's airway during delivery. The anesthesiological management and interdisciplinary tasks are discussed in the literature review.

Adult↗
PubMed2005

[Severe ARDS following perioperative aspiration of gastric content associated with the use of a "ProSeal" laryngeal mask airway].

A ProSeal laryngeal mask airway was used for anaesthesia for laparoscopic surgery in a 26 y old male patient with acute appendicitis. Perioperative aspiration of gastric contents resulted in severe ARDS. Invasive therapeutic options including ECMO had to be used to obtain full recovery. After critical evaluation of the chain of causation it must be postulated that an improper airway was chosen for an intervention that comprises a high risk of aspiration per se. Further risk factors were a long period of fasting, untimely removal of the mask before the patient regained full consciousness, the late confirmation of the diagnosis and the hesitant initial therapy. Since PLMA provides a higher airway occlusion pressure compared to the classic laryngeal mask airway (CLMA), the use of this device may be justified for elective laparoscopic surgery. In emergency patients with increased risk of regurgitation endotracheal intubation still remains the gold standard.

Adult↗