Biomedical subjects

T Bauer

Publications and source records attributed to T Bauer.

At least 73 records · Page 4Linked to original sources

PubMed1996

[Community-acquired pneumonia requiring inpatient treatment: outcome and prognostic rule].

OBJECTIVE: Mortality in community-acquired pneumonia (CAP) may be reduced by early identification of patients requiring intensive care treatment. The purpose of the study was to determine prognostic factors of outcome in patients with CAP in order to establish a clinically applicable discriminant rule. METHODS: 93 episodes of 92 patients with CAP were reviewed with regard to epidemiological, clinical, laboratory and microbiologic data. The prognostic analysis included a univariate as well as a multivariate approach in order to identify parameters correlated with death using the Cox regression hazard function in a backward stepwise selection model. The three parameters found to contribute most to the significance of the model were used in a discriminant rule for classification of outcome. RESULTS: The parameters found to be significantly different between survivors and non-survivors were heart rate, systolic, diastolic as well as mean blood pressures, leucocyte count, percentage of laymphocytes, and LDH values. The multivariate analysis revealed that heart rate, systolic arterial pressure, and LDH serum levels were associated best with lethal outcome (overall significance of the model p < 0.005). A prognostic rule composed of the variables heart rate > or = 90 beats/min, systolic arterial blood pressure < or = 80 mmHg and LDH > or = 260 U/l achieved a sensitivity of 77%, a specificity of 75% and positive and negative predictive values of 42% and 93%, respectively. It was associated with a 6-fold increased risk of lethal outcome. CONCLUSIONS: Heart rate, systolic blood pressure, and LDH values were associated best with death in a multivariate analysis. A discriminant rule consisting of these three variables achieved favourable classification results. The rule qualifies for further prospective validation and may prove useful in the management of hospital treated CAP.

Aged↗

PubMed1995

[Richter hernia in trocar site after laparoscopic herniotomy].

A case of an incarcerated Richter's hernia in a 12-mm trocar site is presented. A 72 year old man underwent laparoscopic herniorrhapy because of a recurrent inguinal hernia. On the sixth postoperative day he developed abdominal pain, nausea, vomiting and abdominal distension. Plain abdominal X-ray showed bowel obstruction. Computed tomography with oral contrast showed herniation of small bowel above the fascia. The patient was immediately reoperated, the intestine was reduced, and the fascial defect at the trocar site closed. Three days later he underwent surgery again due to a small perforation of the small bowel and a persistent fascial defect. The patient had an uneventful postoperative course. Herniation through a trocar site is a rare complication-incarceration extremely rare. We recommend that all fascial defects of 10 mm or more are closed sufficiently.

Aged↗

PubMed1995

[Nodular pulmonary opacities caused by a severe suppurative bronchitis and bronchiectases].

HISTORY AND CLINICAL FINDINGS: A 67-year-old man with chronic obstructive pulmonary disease (COPD) for many years and a heavy smoker was hospitalized because of increasing dyspnoea and moderately productive cough. His general condition was clearly impaired. He was markedly cyanotic, he had a barrel-shaped chest, and there were wheezing rhonchi throughout the lung. Body temperature was 37.8 degrees C. He had mild ankle oedema. The preliminary diagnosis was exacerbation of the COPD with global respiratory failure. TESTS: There was severe hypoxaemia (pO2 48 mm Hg) with hypercapnia (pCO2 46 mm Hg). Vital capacity was reduced to 1.81, one-second forced expiratory volume 0.91. Chest radiograph revealed multiple nodular opacities, such as seen in bronchial carcinoma with metastases. But computed tomography showed fluid-filled bronchi. Bronchoscopy demonstrated large amounts of dirty-white, sticky secretions as high up as the trachea, confirming the preliminary diagnosis. Klebsiella oxytoca and haemophilus influenzae were cultured from the secretions. TREATMENT AND COURSE: Immediate administration of amoxycillin and clavulanic acid (2.2 g daily) quickly led to clinical improvement. Chest x-ray was normalized after 10 days. But long-term oxygen treatment was instituted because of persisting resting hypoxaemia (pO2 46 mm Hg), after which he was discharged free of dyspnoea. CONCLUSION: To clarify nodular pulmonary opacities in a chest radiograph computed tomography should be performed before bronchoscopy.

Aged↗

PubMed1995

Long-term flap tracheostomy in a pediatric animal model.

OBJECTIVE: To investigate the short- and long-term complications of pediatric tracheostomy, emphasizing posttracheostomy tracheal stenosis in an animal model. DESIGN: Twenty-five New Zealand white rabbits were randomly assigned to three groups: flap tracheostomy, traditional vertical tracheostomy, and control. Interactive image analysis was used to compare the tracheal cross-section area and circumference between groups 16 weeks after surgery. The incidence of peristomal infections and accidental decannulations was also compared. RESULTS: The vertical tracheostomy group had a smaller circumference (P = .01) and smaller cross-sectional area (P = .006) than the control or flap tracheostomy groups. A 30% decrease in tracheal cross-sectional area occurred in the vertical tracheostomy group. The flap tracheostomy group had fewer problems with accidental decannulation and peristomal infection compared with the vertical tracheostomy group. CONCLUSIONS: We found no significant risk of tracheal stenosis or adverse effects on tracheal growth for the flap tracheostomy in a developing animal model. This tracheostomy technique may be useful in the management of pediatric patients who require long-term bypass of the upper airway.

Animals↗

PubMed1995

Liver transplantation for hepatic arteriovenous malformation in hereditary haemorrhagic telangiectasia.

Symptomatic hepatic involvement is a rare complication of hereditary hemorrhagic telangiectasia and most commonly consists of fibrosis or cirrhosis. We describe a 33-year-old woman in whom multiple hepatic arteriovenous malformations led to high output cardiac failure and liver failure due to biliary necrosis with refractory biliary sepsis, requiring orthotopic liver transplantation. Hepatic arteriovenous malformations were the first manifestation of the disease and a similar asymptomatic hepatic tumour was subsequently detected in her 60-year-old father who also had the classical cutaneous stigmata of the syndrome. Unrecognised genetic factors may determine the clinical spectrum of hereditary haemorrhagic telangiectasia including the hepatic manifestations.

Adult↗

PubMed1995

The "low intensity treadmill exercise" protocol for appropriate rate adaptive programming of minute ventilation controlled pacemakers.

The objective of rate adaptive pacemakers that measure minute ventilation by transthoracic impedance is to simulate the physiological relationship of the sensed signal to the sinus node response during exercise, thus achieving an appropriate matching of heart rate with patient effort. The purpose of this study was to determine the physiological relationship between heart rate and minute ventilation (HR/VE) during peak exercise testing in order to develop a database for appropriate rate adaptive slope programming of minute ventilation controlled pacemakers. Due to several clinical limitations of peak exercise testing, it was additionally determined whether the 35-watt "low intensity treadmill exercise" (LITE) protocol can be used as a substitute for peak exercise test using the "ramping incremental treadmill exercise" (RITE) protocol in order to assess the correct HR/VE slope below the anaerobic threshold. The stress tests were performed on a treadmill with the collection of breath-by-breath gas exchange. Linear regression analysis was used to determine the HR/VE slope below and above the anaerobic threshold and during the early, dynamic phase of low intensity exercise with the RITE and LITE protocols, respectively. The results of this testing in 41 healthy subjects demonstrated that the HR/VE relationship throughout treadmill exercise using the RITE protocol was not linear but curvilinear in nature, with a steeper HR/VE slope of 1.54 +/- 0.51 below versus 1.15 +/- 0.37 above the anaerobic threshold (P < 0.005). The HR/VE slope determined during the early, dynamic phase of the LITE protocol (1.58 +/- 0.88) did not differ from the HR/VE slope from rest to anaerobic threshold obtained using the peak exercise RITE test (1.54 +/- 0.51; P = 0.79). Rate adaptive pacing should simulate the curvilinear relationship between heart rate and minute ventilation from rest to peak exercise. The HR/VE slope determined during the early, dynamic phase of low intensity exercise represents the HR/VE slope derived from the RITE protocol below the anaerobic threshold. According to the peak exercise database, the slope above anaerobic threshold can easily be calculated as a percentage of the slope below the anaerobic threshold. The LITE protocol can, therefore, be effectively performed as a substitute for peak exercise stress tests to determine the correct pacemaker rate response factor in order to obtain a physiological heart rate to minute ventilation relationship for the appropriate matching of paced heart rate with patient effort.

Anaerobic Threshold↗

PubMed1995

Nursing interventions for spiritual care: preferences of the community-based elderly.

This descriptive correlational study examined the relationships between the three concepts of core spiritual experience, spiritual perspective, and self-transcendence, as well as the spiritual-care nursing interventions preferred by a convenience sample of 50 community-based older adults. Results of single-session interviews indicated significant positive correlations among the three concepts. Spiritual interventions preferred by older adults were those interventions focusing on the therapeutic communication skills of the nurse and the nurse's attitude and approach toward clients. Overall, older adults who believed in a Higher Power and whose beliefs were prominent in their lifestyle rated spiritual nursing interventions as more important than did older adults who did not hold strong beliefs in a Higher Power and whose spiritual beliefs were not prominent in their lifestyle. Findings give direction for providing spiritual nursing care to older adults.

Aged↗

PubMed1995

Prognostic analysis and predictive rule for outcome of hospital-treated community-acquired pneumonia.

In community-acquired pneumonia (CAP) mortality may be reduced by early identification of patients requiring intensive care treatment. The purpose of this study was to determine prognostic factors of outcome in patients with CAP in order to establish a clinically applicable discriminant rule. Ninety three episodes of CAP in 92 patients were retrospectively reviewed with regard to epidemiological, clinical, laboratory and microbiological data. The prognostic analysis included a univariate as well as a multivariate approach, in order to identify parameters associated with death using the Cox regression hazard function in a backward stepwise selection model. The three parameters found to contribute most to the significance of the model were used in a discriminant rule for classification of outcome. The parameters found to be significantly different between survivors and non-survivors were heart rate, systolic and diastolic as well as mean blood pressures, leucocyte count, percentage of lymphocytes, and lactate dehydrogenase (LDH) values. The multivariate analysis revealed that heart rate, systolic arterial pressure, and LDH serum levels were most closely associated with fatal outcome. A prognostic rule composed of the variables heart rate > or = 90 beats.min-1, systolic arterial blood pressure < or = 80 mmHg, and LDH > or = 260 U.l-1 achieved a sensitivity of 77%, a specificity of 75%, and positive and negative predictive values of 42 and 93%, respectively. It was associated with a six fold increased risk of fatal outcome. In conclusion, heart rate, systolic blood pressure, and LDH values were most closely associated with death in a multivariate analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗

PubMed1995

An analysis of desynchronization between the spontaneously breathing patient and ventilator during inspiratory pressure support.

It is common practice to convert patients with acute respiratory insufficiency (ARI) from controlled mechanical ventilation to some form of assisted spontaneous breathing as early as possible. A widely used mode of assisted spontaneous breathing is patient-triggered inspiratory pressure support (IPS). We investigated 11 patients with ARI during weaning from mechanical ventilation using IPS and found that in 9 of these patients, desynchronization between patient and ventilator occurred, ie, that the ventilator did not detect and support all the patients' breathing efforts. Five of these 9 patients displayed severe desynchronization lasting at least 5 min and with less than half of all breathing efforts being supported by the ventilator. We present the analysis of gas flow, volume, esophageal pressure, airway pressure, and tracheal pressure of 1 patient with ARI displaying desynchronization under IPS. Our results imply that desynchronization can occur due to the following: (1) inspiratory response delays caused by the inspiratory triggering mechanisms and the demand flow characteristics of the ventilator; (2) a mismatch between the patient's completion of the inspiration effort and the ventilator's criterion for terminating pressure support; and (3) restriction of expiration due to resistance from patient's airways, endotracheal tube, and expiratory valve. From our analysis, we have made proposals for reducing desynchronization in clinical practice.

Aged↗

PubMed1995

[The MRI in pre- and postnatal diagnosis of congenital sacrococcygeal teratoma].

INTRODUCTION: The main tasks of imaging methods on the evaluation of relatively rare and potentially malignant connatal sacrococcygeal teratomas (SCT) are to depict the extent, structure and relationship to surrounding systems. METHODS: Two cases with SCT were studied with pre- and postnatal MRI and findings were compared with the ultrasound and clinical data. RESULTS: Before delivery, MRI permits depiction of the size and structure of teratomas and the integrity of the serum. After delivery, evaluation of the rectum, urinary tract and levator muscles is important to facilitate surgical reconstruction.

Adult↗

PubMed1995

[MRI and CT in diagnosis and follow-up of idiopathic (retroperitoneal) fibrosis].

Six cases of idiopathic fibrosis are presented to demonstrate the different manifestations of the disease and the efficiency of CT and MRI. In addition to the most common form, retroperitoneal fibrosis (Ormond's disease), fibrosis was seen in the mediastinum and pelvis. The inflammatory aortic aneurysm is a special variant. MRI was superior to CT in many diagnostic requirements. The extent of fibrosis was demonstrated more sensitively and MRI showed sclerosis in regions that appeared normal on CT. Occlusion of large vessels and collateral circulation were better depicted on MRI. The superior tissue contrast of MRI permitted differentiation of several stages of inflammation, which is of major significance for treatment and follow-up.

Adult↗

PubMed1995

Clinical characteristics and outcome of Pneumocystis carinii pneumonia in HIV-infected and otherwise immunosuppressed patients.

The factors contributing to unequal mortality rates following Pneumocystis carinii pneumonia (PCP) in different groups at risk are poorly understood. We therefore compared the first episodes of PCP without prophylaxis in human immunodeficiency virus infected (HIV) and otherwise immunosuppressed patients in this retrospective study. A total of 58 HIV-infected and 16 otherwise immunosuppressed patients were analysed. The comparison included epidemiological, clinical, laboratory, radiological and microbiological data, as well as therapy and clinical course. A prognostic analysis was performed using a logistic regression model. The mortality was significantly different in the two groups (HIV group 17 versus non-HIV group 50%). Renal transplant patients had a higher survival rate as compared to malignancy or collagen vascular disease as underlying diseases at risk. Acute respiratory failure was more common in the non-HIV group. Variables found to be significantly associated with lethal outcome in univariate analysis were alveolar to arterial pressures difference for oxygen (P(A-a),O2), haemoglobin, platelet count, total protein, serum albumin, and gamma-globulins in the HIV-group, and serum albumin in the non-HIV group. In the multivariate analysis of the HIV group, platelet count and gamma-globulins remained independent prognostic factors. In conclusion, in the HIV-group, mortality is closely related to the severeness of PCP as well as to the severeness of the acquired immune deficiency syndrome (AIDS) disease. In the non-HIV group, malignancy and collagen vascular disease as underlying conditions at risk account for the high mortality rate. Its severeness was mainly reflected by serum albumin, which represented the only variable found to be significantly associated with death in both groups.

AIDS-Related Opportunistic Infections↗

PubMed1995

[Diagnostic value of protected bronchoalveolar lavage in HIV-associated pneumonia].

OBJECTIVE: The concept of the protected bronchoalveolar lavage (PBAL) is to improve the diagnostic yield in bacterial pneumonia by unifying the high sensitivity of bronchoalveolar lavage (BAL) and specificity of the protected specimen brush (PSB). HIV-infected patients have been shown to have a high incidence of bacterial pneumonia as well as bacterial colonisation of the tracheobronchial tree. We therefore studied the value of PBAL in this population. METHODS: During a period of twelve months 40 episodes in 36 patients with symptoms suggestive of pneumonia were investigated retrospectively. In all cases without infiltrates on chest radiograph a CT-scan of the chest was performed. Patients without infiltrates also in CT-scan served as controls. Bronchoscopic investigation included a PSB and a PBAL in the same lung segment most prominently affected. Microbiological workup was performed for bacterial agents, mycobacteria, fungi, viruses and parasites. Quantitative cultures for bacteria were considered significant in case of > or equal to 10(3) cfu/ml in PSB and > or equal to 10(4) cfu/ml in PBAL. RESULTS: 32 episodes in 28 patients were identified as pneumonia. A definite diagnosis could be established in 19/32 (59%) of cases. Bacteria accounted for 10/19 (53%). Pneumocystis carinii for 9/19 (47%) of cases including one case that revealed mixed infection with Streptococcus pneumoniae and Pneumocystis carinii. Another pneumonia was due to Aspergillus fumigatus. The sensitivity for bacterial pneumonia was 44% for PSB and 56% for PBAL, the specificity 100%. The overall diagnostic accuracy was 60% and 68%, respectively. The yield for Pneumocystis carinii was 8/9 (89%). CONCLUSIONS: PBAL as compared to PSB had a superior diagnostic yield for bacterial pneumonia. As PBAL additionally conserved the yield of BAL reported for Pneumocystis carinii, it may represent a rational diagnostic technique for pneumonia in HIV-infected patients.

AIDS-Related Opportunistic Infections↗

PubMed1995

[Leptospira infected rat population as probable cause of a fatal case of Weil's disease].

In the summer of 1992 a patient died of a leptospiral infection which he probably had contracted while he was swimming in an artificial lake in the region of Tübingen/Reutlingen. Regarding the epidemiological role of leptospirosis the rodent population was investigated, because rats and mice were often seen in the surrounding area. 11 rats and 20 mice could be trapped. From their urine or kidneys two leptospiral serovars were isolated: Serovar copenhageni from Rattus norvegicus and serovar saxkoebing from Clethrionomys glareolus. Leptospiral antibody titers were not detected in one of these infected animals. It may be supposed that the Leptospira interrogans serovar copenhageni out of the Serogroup Icterohaemorrhagiae had caused the leptospiral infection of the patient.

Animals↗

PubMed1994

Analysis of double-stranded oligonucleotides by electrospray mass spectrometry.

Double-stranded oligonucleotides of different lengths and chemical modification have been analyzed by ion spray mass spectrometry. The non-covalent-bonded duplexes can be detected. Therefore, ion spray mass spectrometry is a useful method for investigation of hybridizations of natural and chemically modified oligonucleotides. Since the exact mass of the double strand can be detected, this method can distinguish between specific and nonspecific interaction.

Base Sequence↗

PubMed1994

Carotid artery stenosis and tachyarrhythmias: regional cerebral blood flow during high-rate ventricular pacing after one vessel occlusion in rats.

The aim of the present study was to investigate the effect of hypotensive tachycardias on cerebral blood flow (CBF) in the presence of significant carotid stenosis. The experiments were performed in 57 spontaneously breathing rats during arterial normoxia and normocapnia anesthetized with thiobarbital. CBF was determined with radiolabeled microspheres during control conditions (normofrequent sinus rhythm, normotension; group A; n = 15), during high-rate left ventricular pacing (660-840 ppm) at normotension (group B1; n = 13), borderline hypotension (group B2; n = 15) and severe hypotension (group B3; n = 7). In addition, CBF measurements were performed during borderline hypotension induced by hemorrhage (group C; n = 7). Global CBF was 1.09 +/- 0.29 ml g-1 min-1 in group A, 0.93 +/- 0.40 in group B1, 0.68 +/- 0.31 in group B2 (P < 0.05 vs. A), 0.42 +/- 0.16 in group B3 (P < 0.05 vs. A) and 0.83 +/- 0.2 in group C. The highest CBF values were found in the cerebellum (A; 1.43 +/- 0.5 ml g-1 min-1) and the lowest in the postocclusive tissue of the ipsilateral hemisphere (A; 0.74 +/- 0.2 ml g-1 min-1). In all groups a 15% mean CBF reduction in the right hemispherical cerebrum in comparison to the left hemisphere was observed (P < 0.01). In contrast, hemispherical CBF of the cerebellum did not differ. The CBF blood pressure relationship shifted to lower CBF values, the threshold of CBF regulation shifted to higher blood pressure values in the tissue regions distal to the occluded vessel during hypotensive tachycardias.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Heart rate during exercise: what is the optimal goal of rate adaptive pacemaker therapy?

The objective of minute ventilation (MV)-controlled pacemaker algorithms is to simulate the physiologic relationship of the sensed signal and the sinus node response during exercise. In our study we determined the relationship between heart rate and MV in healthy middle-aged subjects by measuring breath-by-breath gas exchange throughout peak exercise. Regarding several clinical limitations of peak exercise testing, we additionally evaluated whether a 35 W low-intensity treadmill exercise (LITE) protocol can be used as a substitute for peak exercise testing to determine the physiologic heart rate to MV slope. The results demonstrated that the heart rate to MV relationship is not linear throughout peak exercise but is curvilinear with a smooth logarithmic-type profile. To simulate this relationship, MV-based rate adaptive pacemakers should generate a decreasing heart rate to MV slope during higher levels of work. The heart rate to MV slope determined during the early, dynamic phase of low-intensity exercise represents the same slope derived from peak exercise below the anaerobic threshold. The low-intensity treadmill exercise protocol, with minimal patient effort, can thus be used as a substitute for peak exercise to optimize rate adaptive slope programming of MV-controlled pacemakers.

Algorithms↗

PubMed1994

[MRT and dynamic CT in the diagnosis of a recurrence of rectal carcinoma].

A prospective study on 29 patients with presacral lesions after operation of rectal cancer was performed to define the accuracy of CT using a dynamic contrast study and MRI for detection of tumour recurrence (sensitivity) and differentiation from scar formation (specificity). In dynamic CT sensitivity was 88% and specificity was 100%. In MRI the respective data were 94% (sensitivity) and 92% (specificity). Additionally 14 patients with primary rectal cancer were included to define standards for dynamic CT; no differences between primary tumour and relapse were found. In MRI the assessment of signal intensities in T2w images permits differentiation between tumour relapse and scar tissue. In dynamic CT automatically calculated time-density graphs enable differentiation of presacral lesions and the initial increase of density after standardised bolus application was shown to be the most reliable parameter.

Adult↗