Michael Quintel

Gesellschaft für wissenschaftliche Datenverarbeitung mbH Göttingen, Göttingen, Lower Saxony, Germany

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Publications (87)321.6 Total impact

  • Article: A New Device for Intraoperative Renal Blood Flow Measurement During Open-Heart Surgery: An Experimental Study and the Clinical Pilot Study.
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    ABSTRACT: Renal blood flow (RBF) may vary during cardiopulmonary bypass and low flow may cause insufficient blood supply of the kidney triggering renal failure postoperatively. Still, a valid intraoperative method of continuous RBF measurement is not available. A new catheter combining thermodilution and intravascular Doppler was developed, first calibrated in an in vitro model, and the catheter specific constant was determined. Then, application of the device was evaluated in a pilot study in an adult cardiovascular population. The data of the clinical pilot study revealed high correlation between the flow velocities detected by intravascular Doppler and the RBF measured by thermodilution (Pearson's correlation range: 0.78 to 0.97). In conclusion, the RBF can be measured excellently in real time using the new catheter, even under cardiopulmonary bypass.
    Artificial Organs 05/2013; · 2.00 Impact Factor
  • Article: Bag-mask ventilation and direct laryngoscopy versus intubating laryngeal mask airway: a manikin study of hands-on times during cardiopulmonary resuscitation.
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    ABSTRACT: OBJECTIVES: The percentage of hands-on time during cardiopulmonary resuscitation is a major determinant of patient outcome. We hypothesized that airway management with the intubating laryngeal mask airway (ILMA) would give greater hands-on time than with bag-mask ventilation (BMV), followed by direct laryngoscopy (DL), particularly in difficult-to-manage airways. PARTICIPANTS AND METHODS: Thirty paramedics and 40 medical students performed four standardized, 6-min cardiopulmonary resuscitation scenarios with the SimMan3G in a random sequence. These were normal and difficult-to-manage airways using either BMV+DL or ILMA. RESULTS: The time to the first successful ventilation was significantly longer with the ILMA (P<0.001). Hands-on time was lower for the ILMA after 2 min (67±8 vs. 81±8 s for BMV+DL, P<0.001), but was then significantly greater from the third minute onward (115±11 vs. 104±9 s for BMV+DL, P<0.001). The success rate of the first intubation attempt was higher and the time to ET placement was shorter with the ILMA, especially in the difficult-to-manage airway (P<0.001). CONCLUSION: In this manikin-based study, hands-on time was greater with the ILMA than with BMV+DL. The ILMA was particularly useful in increasing hands-on times in the difficult-to-manage airway.
    European journal of emergency medicine: official journal of the European Society for Emergency Medicine 03/2013; · 0.73 Impact Factor
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    Article: Detection and validation of volatile metabolic patterns over different strains of two human pathogenic bacteria during their growth in a complex medium using multi-capillary column-ion mobility spectrometry (MCC-IMS).
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    ABSTRACT: Headspace analyses over microbial cultures using multi-capillary column-ion mobility spectrometry (MCC-IMS) could lead to a faster, safe and cost-effective method for the identification of pathogens. Recent studies have shown that MCC-IMS allows identification of bacteria and fungi, but no information is available from when on during their growth a differentiation between bacteria is possible. Therefore, we analysed the headspace over human pathogenic reference strains of Escherichia coli and Pseudomonas aeruginosa at four time points during their growth in a complex fluid medium. In order to validate our findings and to answer the question if the results of one bacterial strain can be transferred to other strains of the same species, we also analysed the headspace over cultures from isolates of random clinical origin. We detected 19 different volatile organic compounds (VOCs) that appeared or changed their signal intensity during bacterial growth. These included six VOCs exclusively changing over E. coli cultures and seven exclusively changing over P. aeruginosa cultures. Most changes occurred in the late logarithmic or static growth phases. We did not find differences in timing or trends in signal intensity between VOC patterns of different strains of one species. Our results show that differentiation of human pathogenic bacteria by headspace analyses using MCC-IMS technology is best possible during the late phases of bacterial growth. Our findings also show that VOC patterns of a bacterial strain can be transferred to other strains of the same species.
    Applied Microbiology and Biotechnology 03/2013; · 3.42 Impact Factor
  • Article: Pleural Effusion in Patients With Acute Lung Injury: A CT Scan Study.
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    ABSTRACT: OBJECTIVES:: Pleural effusion is a frequent finding in patients with acute respiratory distress syndrome. To assess the effects of pleural effusion in patients with acute lung injury on lung volume, respiratory mechanics, gas exchange, lung recruitability, and response to positive end-expiratory pressure. DESIGN, SETTING, AND PATIENTS:: A total of 129 acute lung injury or acute respiratory distress syndrome patients, 68 analyzed retrospectively and 61 prospectively, studied at two University Hospitals. INTERVENTIONS:: Whole-lung CT was performed during two breath-holding pressures (5 and 45 cm H2O). Two levels of positive end-expiratory pressure (5 and 15 cm H2O) were randomly applied. MEASUREMENTS:: Pleural effusion volume was determined on each CT scan section; respiratory system mechanics, gas exchange, and hemodynamics were measured at 5 and 15 cm H2O positive end-expiratory pressure. In 60 patients, elastances of lung and chest wall were computed, and lung and chest wall displacements were estimated. RESULTS:: Patients were divided into higher and lower pleural effusion groups according to the median value (287 mL). Patients with higher pleural effusion were older (62 ± 16 yrs vs. 54 ± 17 yrs, p < 0.01) with a lower minute ventilation (8.8 ± 2.2 L/min vs. 10.1 ± 2.9 L/min, p < 0.01) and respiratory rate (16 ± 5 bpm vs. 19 ± 6 bpm, p < 0.01) than those with lower pleural effusion. Both at 5 and 15 cm H2O of positive end-expiratory pressure PaO2/FIO2, respiratory system elastance, lung weight, normally aerated tissue, collapsed tissue, and lung and chest wall elastances were similar between the two groups. The thoracic cage expansion (405 ± 172 mL vs. 80 ± 87 mL, p < 0.0001, for higher pleural effusion group vs. lower pleural effusion group) was greater than the estimated lung compression (178 ± 124 mL vs. 23 ± 29 mL, p < 0.0001 for higher pleural effusion group vs. lower pleural effusion group, respectively). CONCLUSIONS:: Pleural effusion in acute lung injury or acute respiratory distress syndrome patients is of modest entity and leads to a greater chest wall expansion than lung reduction, without affecting gas exchange or respiratory mechanics.
    Critical care medicine 02/2013; · 6.37 Impact Factor
  • Article: Effects of acute intracranial hypertension on extracerebral organs: a randomized experimental study in pigs.
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    ABSTRACT: The study was conducted to determine the effects of isolated acute intracranial hypertension (AICH) on extracerebral organs. A total of 14 mechanically ventilated pigs were randomized to two groups of seven each: (1) control and (2) AICH. AICH was induced by inflating an intracranial balloon catheter. The inflation volume was adjusted to keep intracranial pressure between 30 and 40 cm H2O. Hemodynamics, gas-exchange, and global oxygen delivery parameters were observed over a 4-hour period. At the end of the 4-hour period, tissue samples of heart, lungs, liver, and kidneys were collected and histologically graded for inflammation, edema, and cell damage (necrosis) using semiquantitative scores. Animals with AICH had increased heart rate and cardiac output, and higher scores for inflammation, edema, and necrosis in heart, lung, kidney, and liver tissues (all p < 0.05). Peripheral and mixed-venous oxygen saturations were unaffected. Isolated AICH induces injury to multiple extracerebral organs, even in the absence of hypoperfusion or hypoxemia.
    Journal of neurological surgery. Part A, Central European neurosurgery. 08/2012; 73(5):289-95.
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    Article: Mild metabolic acidosis impairs the beta-adrenergic response in isolated human failing myocardium.
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    ABSTRACT: INTRODUCTION: Pronounced extracellular acidosis reduces both cardiac contractility and the beta-adrenergic response. In the past this was shown in some studies using animal models. However, only few data exist regarding how the human end-stage failing myocardium, in which compensatory mechanisms are exhausted, reacts to acute mild metabolic acidosis. The aim of this study was to investigate the effect of mild metabolic acidosis on contractility and betaadrenergic response of isolated trabeculae from human end-stage failing hearts. METHODS: Intact isometrically twitching trabeculae isolated from patients with end-stage heart failure were exposed to mild metabolic acidosis (pH=7.20). Trabeculae were stimulated at increasing frequencies and finally exposed to increasing concentrations of isoproterenol (0 to 1*10-6 mol/L). RESULTS: A mild metabolic acidosis caused a depression in twitch force amplitude of 26% (12.1+/-1.9 to 9.0+/-1.5 mN/mm2, n=12, P<0.01) as compared to pH 7.40. Force-frequency relation measurements yielded no further significant differences of twitch force. At the maximal isoproterenol concentration, the force amplitude was comparable in each of the two groups (pH 7.40 vs. pH 7.20). However, the half maximal effective concentration (EC50) was significantly increased in the acidosis group, with an EC50 of 5.834x10-8 mol/L (confidence interval [CI] 3.48x10-8 - 9.779x10-8, n=9), compared with the control group, which had an EC50 of 1.056x10-8 mol/L (CI 2.626x10-9 - 4.243x10-8, n=10, P<0.05), indicating an impaired beta-adrenergic force response. CONCLUSIONS: Our data show that mild metabolic acidosis reduces cardiac contractility and significantly impairs the beta-adrenergic force response in human failing myocardium. Thus, our results could contribute to the still controversial discussion about the therapy regimen of acidosis in patients with critical heart failure.
    Critical care (London, England) 08/2012; 16(4):R153. · 4.61 Impact Factor
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    Article: On-line determination of serum propofol concentrations by expired air analysis
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    ABSTRACT: Propofol (2,6-diisopropylphenol)—an intravenous anaesthetic—can be identified and quantified in expired air directly. For the first time, a β-radiation ion mobility spectrometer operated in the positive mode and coupled to a multi-capillary column for rapid (seconds–minutes) pre-separation (MCC/IMS) was used for the quantification of Propofol in expired air. The comparison of the concentrations in exhaled air (300pptV–5ppbV) and in serum (0.3–5μg/mL) showed satisfying agreement affirmed by a correlation coefficient of 0.73. Therefore, MCC/IMS is an adequate method to determine Propofol concentrations in exhaled air and may be applied for the prediction of venous concentrations or for automatic anaesthesia control. KeywordsPropofol-2,6-diisopropylphenol-Anaesthesia-Serum-TIVA-Breath analysis-Ion mobility spectrometry-GC/MS-GC/IMS
    International Journal for Ion Mobility Spectrometry 04/2012; 13(1):37-40.
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    Article: Effects of pulmonary acid aspiration on the lungs and extra-pulmonary organs: a randomized study in pigs.
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    ABSTRACT: ABSTRACT: INTRODUCTION: There is mounting evidence that injury to one organ causes indirect damage to other organ systems with increased morbidity and mortality. The aim of this study was to determine the effects of acid aspiration pneumonitis (AAP) on extrapulmonary organs and to test the hypothesis that these could be due to circulatory depression or hypoxemia. METHODS: Mechanically ventilated anesthetized pigs were randomized to receive intrabronchial instillation of hydrochloric acid (n = 7) or no treatment (n = 7). Hydrochloric acid (0.1 N, pH 1.1, 2.5 ml/kg BW) was instilled into the lungs during the inspiratory phase of ventilation. Hemodynamics, respiratory function and computer tomography (CT) scans of lung and brain were followed over a four-hour period. Tissue samples of lung, heart, liver, kidney and hippocampus were collected at the end of the experiment. RESULTS: Acid instillation caused pulmonary edema, measured as increased extravascular lung water index (ELWI), impaired gas exchange and increased mean pulmonary artery pressure. Gas exchange tended to improve during the course of the study, despite increasing ELWI. In AAP animals compared to controls we found: a) cardiac leukocyte infiltration and necrosis in the conduction system and myocardium; b) lymphocyte infiltration in the liver, spreading from the periportal zone with prominent areas of necrosis; c) renal inflammation with lymphocyte infiltration, edema and necrosis in the proximal and distal tubules; and d) a tendency towards more severe hippocampal damage (P > 0.05). CONCLUSIONS: Acid aspiration pneumonitis induces extrapulmonary organ injury. Circulatory depression and hypoxemia are unlikely causative factors. ELWI is a sensitive bedside parameter of early lung damage.
    Critical care (London, England) 03/2012; 16(2):R35. · 4.61 Impact Factor
  • Article: Ion mobility spectrometry for microbial volatile organic compounds: a new identification tool for human pathogenic bacteria.
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    ABSTRACT: Presently, 2 to 4 days elapse between sampling at infection suspicion and result of microbial diagnostics. This delay for the identification of pathogens causes quite often a late and/or inappropriate initiation of therapy for patients suffering from infections. Bad outcome and high hospitalization costs are the consequences of these currently existing limited pathogen identification possibilities. For this reason, we aimed to apply the innovative method multi-capillary column-ion mobility spectrometry (MCC-IMS) for a fast identification of human pathogenic bacteria by determination of their characteristic volatile metabolomes. We determined volatile organic compound (VOC) patterns in headspace of 15 human pathogenic bacteria, which were grown for 24 h on Columbia blood agar plates. Besides MCC-IMS determination, we also used thermal desorption-gas chromatography-mass spectrometry measurements to confirm and evaluate obtained MCC-IMS data and if possible to assign volatile compounds to unknown MCC-IMS signals. Up to 21 specific signals have been determined by MCC-IMS for Proteus mirabilis possessing the most VOCs of all investigated strains. Of particular importance is the result that all investigated strains showed different VOC patterns by MCC-IMS using positive and negative ion mode for every single strain. Thus, the discrimination of investigated bacteria is possible by detection of their volatile organic compounds in the chosen experimental setup with the fast and cost-effective method MCC-IMS. In a hospital routine, this method could enable the identification of pathogens already after 24 h with the consequence that a specific therapy could be initiated significantly earlier.
    Applied Microbiology and Biotechnology 03/2012; 93(6):2603-14. · 3.42 Impact Factor
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    Article: Cost analysis of two anaesthetic machines: "Primus®" and "Zeus®".
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    ABSTRACT: Two anaesthetic machines, the "Primus®" and the "Zeus®" (Draeger AG, Lübeck, Germany), were subjected to a cost analysis by evaluating the various expenses that go into using each machine. These expenses included the acquisition, maintenance, training and device-specific accessory costs. In addition, oxygen, medical air and volatile anaesthetic consumption were determined for each machine. Anaesthesia duration was 278 ± 140 and 208 ± 112 minutes in the Primus® and the Zeus®, respectively. The purchase cost was €3.28 and €4.58 per hour of operation in the Primus® and the Zeus®, respectively. The maintenance cost was €0.90 and €1.20 per hour of operation in the Primus® and the Zeus®, respectively. We found that the O2 cost was €0.015 ± 0.013 and €0.056 ± 0.121 per hour of operation in the Primus® and the Zeus®, respectively. The medical air cost was €0.005 ± 0.003 and €0.016 ± 0.027 per hour of operation in the Primus® and the Zeus®, respectively. The volatile anaesthetic cost was €2.40 ± 2.40 and €4.80 ± 4.80 per hour of operation in the Primus® and the Zeus®, respectively. This study showed that the "Zeus®" generates a higher cost per hour of operation compared to the "Primus®".
    BMC Research Notes 01/2012; 5:3.
  • Article: Predicting restoration of kidney function during CRRT-free intervals.
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    ABSTRACT: Renal failure is common in critically ill patients and frequently requires continuous renal replacement therapy (CRRT). CRRT is discontinued at regular intervals for routine changes of the disposable equipment or for replacing clogged filter membrane assemblies. The present study was conducted to determine if the necessity to continue CRRT could be predicted during the CRRT-free period. In the period from 2003 to 2006, 605 patients were treated with CRRT in our ICU. A total of 222 patients with 448 CRRT-free intervals had complete data sets and were used for analysis. Of the total CRRT-free periods, 225 served as an evaluation group. Twenty-nine parameters with an assumed influence on kidney function were analyzed with regard to their potential to predict the restoration of kidney function during the CRRT-free interval. Using univariate analysis and logistic regression, a prospective index was developed and validated in the remaining 223 CRRT-free periods to establish its prognostic strength. Only three parameters showed an independent influence on the restoration of kidney function during CRRT-free intervals: the number of previous CRRT cycles (medians in the two outcome groups: 1 vs. 2), the "Sequential Organ Failure Assessment"-score (means in the two outcome groups: 8.3 vs. 9.2) and urinary output after the cessation of CRRT (medians in two outcome groups: 66 ml/h vs. 10 ml/h). The prognostic index, which was calculated from these three variables, showed a satisfactory potential to predict the kidney function during the CRRT-free intervals; Receiver operating characteristic (ROC) analysis revealed an area under the curve of 0.798. Restoration of kidney function during CRRT-free periods can be predicted with an index calculated from three variables. Prospective trials in other hospitals must clarify whether our results are generally transferable to other patient populations.
    Journal of Cardiothoracic Surgery 01/2012; 7:6. · 1.19 Impact Factor
  • Article: Incidence of difficult intubation in intensive care patients: analysis of contributing factors.
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    ABSTRACT: Difficulties in endotracheal intubation increase morbidity and mortality in intensive care patients. We studied the problem in surgical intensive care patients with the aim of risk reduction. Patients intubated in the intensive care unit were evaluated. The intubations were performed or supervised by anaesthetists following the algorithm valid at the time of the study. Fifty percent of the 198 intubations were performed by specialist anaesthetists, 41.5% by anaesthesia trainees and 8.5% by surgical trainees. The initial attempt was by direct laryngoscopy (n=173), flexible fibrescope (n=8) or blind nasal technique (n=17). When direct laryngoscopy failed (n=7), intubation was accomplished with an intubating laryngeal mask airway (n=5), Frova stylet (n=1) or fibrescope (n=1). Thirty percent were rated as easy, 47% as moderately easy and 23% as difficult. Difficult intubations were associated with a higher incidence of anatomic anomalies, difficult bag-mask ventilation and severe oxygen desaturation. Every intubation in the ICU setting should be considered potentially difficult. The existing algorithm should be modified to incorporate the American Society of Anesthesiologists difficult airway algorithm adapted to the needs of the intensive care unit. A training program for alternative methods of airway management for difficult intubations should be established.
    Anaesthesia and intensive care 01/2012; 40(1):120-7. · 1.28 Impact Factor
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    Article: Influence of body position, PEEP and intra-abdominal pressure on the catheter positioning for neurally adjusted ventilatory assist.
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    ABSTRACT: Neurally adjusted ventilatory assist (NAVA) relies on the patient's electrical activity of the diaphragm (EAdi) for actuating the ventilator. Thus a reliable positioning of the oesophageal EAdi catheter is mandatory. We aimed to evaluate the effects of body position (BP), positive end-expiratory pressure (PEEP) and intra-abdominal pressure (IAP) on catheter positioning. Twenty-one patients were enrolled in this study. In six different situations [supine or 45° head of bed elevation (HBE) at PEEP 5 and 15 cmH(2)O; left lateral anti-decubitus at PEEP 5 cmH(2)O; supine at PEEP 5 cmH(2)O with abdominal surgical belt (ASB)] the catheter position was evaluated for the stability of the EAdi signal and information provided by a catheter positioning tool (highlighted electrical activity in central leads, absence of p waves in the distal lead). With an optimal catheter position EAdi signals were stable for all tested situations. During "45° PEEP 15" and "supine PEEP 15" absence of p waves in the distal lead revealed a difference compared with "supine PEEP 5" (p = 0.03), suggesting a caudal shift of the diaphragm relative to the oesophagus. The analysis of the highlighted electrical activity in the central leads supports this finding, revealing an influence of PEEP, BP and IAP on EAdi catheter position (p < 0.01). PEEP, BP and IAP may affect the EAdi catheter position, although not compromising a stable signal. Additional information as provided by the catheter positioning tool is needed to ensure an optimal EAdi catheter position.
    European Journal of Intensive Care Medicine 12/2011; 37(12):2041-5. · 5.17 Impact Factor
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    Article: Impact of physical fitness and biometric data on the quality of external chest compression: a randomised, crossover trial.
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    ABSTRACT: During circulatory arrest, effective external chest compression (ECC) is a key element for patient survival. In 2005, international emergency medical organisations changed their recommended compression-ventilation ratio (CVR) from 15:2 to 30:2 to acknowledge the vital importance of ECC. We hypothesised that physical fitness, biometric data and gender can influence the quality of ECC. Furthermore, we aimed to determine objective parameters of physical fitness that can reliably predict the quality of ECC. The physical fitness of 30 male and 10 female healthcare professionals was assessed by cycling and rowing ergometry (focussing on lower and upper body, respectively). During ergometry, continuous breath-by-breath ergospirometric measurements and heart rate (HR) were recorded. All participants performed two nine-minute sequences of ECC on a manikin using CVRs of 30:2 and 15:2. We measured the compression and decompression depths, compression rates and assessed the participants' perception of exhaustion and comfort. The median body mass index (BMI; male 25.4 kg/m2 and female 20.4 kg/m2) was used as the threshold for subgroup analyses of participants with higher and lower BMI. HR during rowing ergometry at 75 watts (HR75) correlated best with the quality of ECC (r = -0.57, p < 0.05). Participants with a higher BMI and better physical fitness performed better and showed less fatigue during ECC. These results are valid for the entire cohort, as well as for the gender-based subgroups. The compressions of female participants were too shallow and more rapid (mean compression depth was 32 mm and rate was 117/min with a CVR of 30:2). For participants with a lower BMI and higher HR75, the compression depth decreased over time, beginning after four minutes for the 15:2 CVR and after three minutes for the 30:2 CVR. Although found to be more exhausting, a CVR of 30:2 was rated as being more comfortable. The quality of the ECC and fatigue can both be predicted by BMI and physical fitness. An evaluation focussing on the upper body may be a more valid predictor of ECC quality than cycling based tests. Our data strongly support the recommendation to relieve ECC providers after two minutes.
    BMC Emergency Medicine 11/2011; 11:20.
  • Article: Influence of mild metabolic acidosis on cardiac contractility and isoprenaline response in isolated ovine myocardium.
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    ABSTRACT: The postoperative course after major surgical procedures such as cardiothoracic operations is often accompanied by acute metabolic abnormalities due to large volume and temperature shifts. In general, those intervention-induced trauma might cause the use of catecholamines to stabilize hemodynamics. Within the cardiac community, there are still controversial discussions about standardized medical therapy to treat postoperative acidosis, for example, buffering versus nonbuffering for improving catecholaminergic response of myocardial contractility. The aim of this study was to investigate the influence of mild (and thus clinically relevant) acidosis on myocardial contractility and catecholamine response in explanted trabeculae of ovine hearts. Intact trabeculae (n = 24) were isolated from the right ventricle of healthy sheep hearts. Two different groups (group 1: pH = 7.40, n = 9 and group 2: pH = 7.20, n = 13) were investigated, and force amplitudes were measured at frequencies between 30 and 180 beats per minute and increasing catecholamine concentrations (isoprenaline 0-3 × 10(-6) mM). Force-frequency relation experiments in the presence of a physiological and/or mild acidotic pH solution showed no significant differences. Mean force amplitudes normalized to the lowest frequency showing no significant differences in force development between 0.5 and 3 Hz (n = 9 vs. 13, P = n.s.) (0.5 Hz absolute values 3.1 ± 2.6 for pH = 7.40 vs. 3.8 ± 2.6 mN/mm(2) for pH = 7.20, P = n.s.). Moreover, there was no significant difference in relaxation kinetics between the two groups. Furthermore, the experiments showed similar catecholamine responses in both groups. Force amplitudes normalized to baseline and maximum force showed no significant differences in force development between baseline and maximum isoprenaline concentrations (n = 6 vs. 9, P = n.s.) (baseline absolute values 4.3 ± 4.0 for pH = 7.40 vs. 3.9 ± 1.2 mN/mm(2) for pH = 7.20, P = n.s.). Additionally, relaxation kinetics did not show differences after catecholamine stimulation. The presented experiments revealed no significant negative inotropic effects on isometrically contracting ovine trabeculae with mild metabolic acidosis (pH = 7.2) compared with physiological pH (7.4). Additionally, similar catecholamine responses were seen in both groups. Further investigations (e.g., in vivo and/or in failing hearts with reduced compensatory reserves) will be necessary to examine optimal medical treatment for metabolic abnormalities after cardiac surgery.
    Artificial Organs 11/2011; 35(11):1065-74. · 2.00 Impact Factor
  • Article: Accuracy of prehospital diagnoses by emergency physicians: comparison with discharge diagnosis.
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    ABSTRACT: A correct prehospital diagnosis of emergency patients is crucial as it determines initial treatment, admitting specialty, and subsequent treatment. We evaluated the diagnostic accuracy of emergency physicians. All patients seen by six emergency physicians staffing the local emergency ambulance and rescue helicopter services during an 8-month period were studied. The ambulance and helicopter physicians had 3 and 4 years, respectively, training in anesthesia and intensive care medicine. The admission diagnoses were compared with the discharge diagnoses for agreement. Time of day of the emergency call, patients' age, and sex, living conditions, and presenting symptoms were evaluated as contributing factors. Three hundred and fifty-five ambulance and 241 helicopter deployment protocols were analyzed. The overall degree of agreement between initial and discharge diagnoses was 90.1% with no difference attributable to years of experience. The lowest agreement rate was seen in neurological disorders (81.5%), with a postictal state after an unobserved seizure often being diagnosed as a cerebrovascular accident. Inability to obtain a complete medical history (e.g. elderly patients, patients in nursing homes, neurological impairment) was associated with a lower agreement rate between initial and discharge diagnoses (P<0.05). Medical history, physical examination, ECG, and blood glucose enabled a correct diagnosis in most cases, but some were impossible to resolve without further technical and laboratory investigations. Only a few were definitively incorrect. A detailed medical history is essential. Neurological disorders can present with misleading symptoms and when the diagnosis is not clear it is better to assume the worst case.
    European journal of emergency medicine: official journal of the European Society for Emergency Medicine 10/2011; 19(5):292-6. · 0.73 Impact Factor
  • Article: Cardiopulmonary function and oxygen delivery during total liquid ventilation
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    ABSTRACT: IntroductionTotal liquid ventilation (TLV) with perfluorocarbons has shown to improve cardiopulmonary function in the injured and immature lung; however there remains controversy over the normal lung. Hemodynamic effects of TLV in the normal lung currently remain undetermined. This study compared changes in cardiopulmonary and circulatory function caused by either liquid or gas tidal volume ventilation.Methods In a prospective, controlled study, 12 non-injured anesthetized, adult New Zealand rabbits were primarily conventionally gas-ventilated (CGV). After instrumentation for continuous recording of arterial (AP), central venous (CVP), left artrial (LAP), pulmonary arterial pressures (PAP), and cardiac output (CO) animals were randomized into (1) CGV group and (2) TLV group. In the TLV group partial liquid ventilation was initiated with instillation of perfluoroctylbromide (12 ml/kg). After 15 min, TLV was established for 3 hr applying a volume-controlled, pressure-limited, time-cycled ventilation mode using a double-piston configured TLV. Controls (CGV) remained gas-ventilated throughout the experiment.ResultsDuring TLV, heart rate, CO, PAP, MAP, CVP, and LAP as well as derived hemodynamic variables, arterial and mixed venous blood gases, oxygen delivery, PVR, and SVR did not differ significantly compared to CGV.Conclusions Liquid tidal volumes suitable for long-term TLV in non-injured rabbits do not significantly impair CO, blood pressure, and oxygen dynamics when compared to CGV. Pediatr. Pulmonol. 2011; 46:964–975. © 2011 Wiley-Liss, Inc.
    Pediatric Pulmonology 09/2011; 46(10):964 - 975. · 2.53 Impact Factor
  • Article: Early out-of-hospital non-invasive ventilation is superior to standard medical treatment in patients with acute respiratory failure: a pilot study.
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    ABSTRACT: To assess in patients with acute respiratory failure (ARF) whether out-of-hospital (OOH) non-invasive ventilation (NIV) is feasible, safe and more effective compared with standard medical therapy (SMT). Patients with OOH ARF were randomly assigned to receive either SMT or NIV. Fifty-one patients were enrolled, 26 of whom were randomly assigned to SMT and 25 of whom received NIV. Two patients were excluded because of protocol violations. OOH NIV was safe and effective in all patients. In the SMT group, treatment was not effective in five of 25 patients who required OOH mechanical ventilation (p=0.05). Patients in the SMT group were admitted to an intensive care unit (ICU) more frequently (n=17) (p<0.05) and for longer periods (3.7±6.4 days) (p=0.03) compared with patients in the NIV group (n=9, 1.3±2.6 days). Six patients in the SMT group required subsequent inhospital intubation and invasive ventilation during their hospital stays; only one patient in the NIV group required intubation (p=0.10). In contrast, patients in the NIV group received NIV more frequently (n=14) in hospital compared with patients in the SMT group (n=5) (p<0.01). OOH NIV proved to be feasible, safe and more effective for the treatment of ARF compared with SMT. OOH NIV promotes inhospital treatment with NIV and may reduce the frequency and length of ICU stays. Because the risks of OOH emergency intubation can be avoided, NIV should be the first-line treatment in OOH ARF if no contraindications are present.
    Emergency Medicine Journal 09/2011; 29(5):409-14. · 1.44 Impact Factor
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    Article: Intensified thermal management for patients undergoing transcatheter aortic valve implantation (TAVI).
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    ABSTRACT: Transcatheter aortic valve implantation via the transapical approach (TAVI-TA) without cardiopulmonary bypass (CPB) is a minimally invasive alternative to open-heart valve replacement. Despite minimal exposure and extensive draping perioperative hypothermia still remains a problem. In this observational study, we compared the effects of two methods of thermal management on the perioperative course of core temperature. The methods were standard thermal management (STM) with a circulating hot water blanket under the patient, forced-air warming with a lower body blanket and warmed infused fluids, and an intensified thermal management (ITM) with additional prewarming using forced-air in the pre-operative holding area on the awake patient. Nineteen patients received STM and 20 were treated with ITM. On ICU admission, ITM-patients had a higher core temperature (36.4±0.7°C vs. 35.5±0.9°C, p=0.001), required less time to achieve normothermia (median (IQR) in min: 0 (0-15) vs. 150 (0-300), p=0.003) and a shorter period of ventilatory support (median (IQR) in min: 0 (0-0) vs. 246 (0-451), p=0.001). ITM during TAVI-TA reduces the incidence of hypothermia and allows for faster recovery with less need of ventilatory support.
    Journal of Cardiothoracic Surgery 09/2011; 6:117. · 1.19 Impact Factor
  • Article: The presence of functionally relevant toll-like receptor polymorphisms does not significantly correlate with development or outcome of sepsis.
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    ABSTRACT: Members of the toll-like receptor (TLR) family have been shown to play important roles in inflammatory responses. Single-nucleotide polymorphisms (SNPs) altering receptor activity may either have detectable effects or might be without results due to compensatory mechanisms. We determined the genotype frequencies of functionally relevant SNPs in TLR2, 4 and 5 in critically ill patients (n=150) from a multidisciplinary surgical intensive care unit (ICU). The inflammatory response (procalcitonin, C-reactive protein, white blood count) and clinical classification (Acute Physiology and Chronic Health Evaluation Score II, Simplified Acute Physiology Score II, Sepsis-related Organ Failure Assessment) were monitored daily. The genetic polymorphisms correlate with neither development nor outcome of sepsis. No correlations were found between C-reactive protein or WBC and the investigated SNPs. In patients in the ICU with abdominal surgery and multiple trauma, the TLR2-R753Q SNP was associated with infection at ICU admission (p<0.01); and for carriers of the TLR4-D299G SNP, a trend was observed (p=0.0776). Patients with multiple trauma carrying the TLR4-D299G SNP displayed significantly higher levels of procalcitonin (p=0.0212). None of the investigated SNPs clearly predicted outcome of sepsis-related multiorgan failure. TLR2-R753Q SNP may be a useful marker to identify patients with high risk to develop infections at ICU admission but should be validated in larger studies. Future SNP-arrays investigating predisposition for infection should include this SNP alone or in combination with other functionally relevant SNPs.
    Genetic Testing and Molecular Biomarkers 07/2011; 15(9):645-51. · 1.11 Impact Factor

Institutions

  • 2012
    • Gesellschaft für wissenschaftliche Datenverarbeitung mbH Göttingen
      Göttingen, Lower Saxony, Germany
  • 2006–2011
    • Georg-August-Universität Göttingen
      • Center for Anesthesiology, Emergency and Intensive Care Medicine
      Göttingen, Lower Saxony, Germany
  • 2009–2010
    • Charité Universitätsmedizin Berlin
      • Department of Anesthesiology and Operative Intensive Care Medicine
      Berlin, Land Berlin, Germany
    • University of Milan
      • Department of Anesthesia, Intensive Care and Dermatologic Sciences
      Milano, Lombardy, Italy
  • 2004
    • Universität Mannheim
      Mannheim, Baden-Wuerttemberg, Germany
  • 2003–2004
    • Universität Heidelberg
      • • Faculty of Medicine Mannheim and Clinic Mannheim
      • • Department of Anesthesiology and Critical Care Medicine
      Heidelberg, Baden-Wuerttemberg, Germany