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M Hiesmayr

Publications and source records attributed to M Hiesmayr.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Protein catabolism after lung transplantation and heart transplantation].

Any surgical intervention is associated with an activation of protein catabolism, the extent of which is dependent on the severity of surgical trauma. There is a paucity of reports on protein catabolism after transplantation of chest organs (lung transplantation (LTX) and heart transplantation (HTX)). The aim of the present study was to quantify and compare the extent of postoperative protein catabolism and associated metabolic perturbations in patients after LTX and HTX. Eighteen consecutive patients after LTX and 15 consecutive patients after HTX who required postoperative intensive care for more than 4 days, constituted the study population. The nitrogen balance (assessed on the basis of the urea nitrogen production rate and nitrogen intake) was assessed retrospectively and correlated with insulin requirements, immunosuppression and the clinical course. Within the first 5 days the nitrogen balance became progressively negative in both groups, reaching a maximum on the 5th day. Thereafter the nitrogen balance of patients following LTX remained negative, whereas the nitrogen balance of patients following HTX tended to improve. The evolution of nitrogen balance significantly differed between both groups (p < 0.01). The mean nitrogen loss was -0.29 +/- 0.17g/kg BW/day after LTX versus -0.22 +/- 0.12g/kg BW/day after HTX. Smaller amounts of glucocorticoids were used for immunosuppression in patients after HTX than in patients after LTX; nevertheless, heart transplant recipients required higher doses of insulin to maintain normoglycemia. A regression analysis revealed that the duration of stay at the intensive care unit (p < 0.001) and the amount of glucocorticoids (p < 0.01) negatively affected the nitrogen balance, whereas an increased protein intake (p < 0.001) exerted a positive effect. Compared to other major surgical procedures, protein catabolism is excessively elevated in patients after thoracic transplantation. Immunosuppressive therapy with glucocorticoids contributes to protein degradation; the nitrogen balance after LTX is more negative than that after HTX because of higher glucocorticoid requirements following LTX. More aggressive nutritional intervention and especially an increased nitrogen intake might help to reduce protein losses in these patients.

Adult↗
PubMed1998

[Risk and procedure education in anesthesiology. Overview of Austrian and German legal regulations].

Informed consent is currently an ethical, medical and legal requirement. An increase in public discussion of real or supposed malpractice has led to critical attitude in patients and increased demands on informed consent by the courts. Unfortunately, the legal requirements of informed consent have developed from atypical situations involving dissatisfied and injured patients rather than from the more usual occurrences of physicians helping patients with subsequent patient satisfaction. In addition, laws have not set forth clear guidelines for physicians to follow. We review the elements of informed consent based on current Austrian and German jurisdiction in the particular field of anesthesiology and summarize the legal and medical realities in order to point out specific criteria for decision making.

Anesthesiology↗
PubMed1998

Tissue heat content and distribution during and after cardiopulmonary bypass at 31 degrees C and 27 degrees C.

BACKGROUND: Afterdrop following cardiopulmonary bypass results from redistribution of body heat to inadequately warmed peripheral tissues. However, the distribution of heat between the thermal compartments and the extent to which core-to-peripheral redistribution contributes to post-bypass hypothermia remains unknown. METHODS: Patients were cooled during cardiopulmonary bypass to nasopharyngeal temperatures near 31 degrees C (n=8) or 27 degrees C (n=8) and subsequently rewarmed by the bypass heat exchanger to approximately 37.5 degrees C. A nasopharyngeal probe evaluated core (trunk and head) temperature and heat content. Peripheral compartment (arm and leg) temperature and heat content were estimated using fourth-order regressions and integration over volume from 19 intramuscular needle thermocouples, 10 skin temperatures, and "deep" foot temperature. RESULTS: In the 31 degrees C group, the average peripheral tissue temperature decreased to 31.9+/-1.4 degrees C (means+/-SD) and subsequently increased to 34+/-1.4 degrees C at the end of bypass. The core-to-peripheral tissue temperature gradient was 3.5+/-1.8 degrees C at the end of rewarming, and the afterdrop was 1.5+/-0.4 degrees C. Total body heat content decreased 231+/-93 kcal. During pump rewarming, the peripheral heat content increased to 7+/-27 kcal below precooling values, whereas the core heat content increased to 94+/-33 kcal above precooling values. Body heat content at the end of rewarming was thus 87+/-42 kcal more than at the onset of cooling. In the 27 degrees C group, the average peripheral tissue temperature decreased to a minimum of 29.8 +/-1.7 degrees C and subsequently increased to 32.8+/-2.1 degrees C at the end of bypass. The core-to-peripheral tissue temperature gradient was 4.6+/-1.9 degrees C at the end of rewarming, and the afterdrop was 2.3+/-0.9 degrees C. Total body heat content decreased 419+/-49 kcal. During pump rewarming, core heat content increased to 66+/-23 kcal above precooling values, whereas peripheral heat content remained 70+/-42 kcal below precooling values. Body heat content at the end of rewarming was thus 4+/-52 kcal less than at the onset of cooling. CONCLUSIONS: Peripheral tissues failed to fully rewarm by the end of bypass in the patients in the 27 degrees C group, and the afterdrop was 2.3+/-0.9 degrees C. Peripheral tissues rewarmed better in the patients in the 31 degrees C group, and the afterdrop was only 1.5+/-0.4 degrees C.

Adult↗
PubMed1997

[Definition and evaluation of a documentation standard for intensive care medicine: the ASDI(Working Group for Standardization of a documentation system for Intensive care medicine) pilot project].

OBJECTIVES: A comparison of data from different intensive care units (ICUs) needs standardized documentation. In this study the ASDI documentation standard for intensive care was tested in clinical practice. Goal of the study was to evaluate parameters and functionality required for a national, interdisciplinary documentation system for intensive care. DESIGN: 13 ICUs participated in a 4-week trial using the provided program for documentation of all admitted patients during the observation period. In addition, a questionnaire was distributed to the unit coordinators. RESULTS: 376 patients were documented in 1591 patient days. Valid SAPS II scores were found in only 29% of the discharged patients (39.1 +/- 15.5 points). Time needed for data entry exceeded preset limits (ten minutes per patient and day) in 38% of the cases. All participants affirmed the necessity of a documentation standard for intensive care, giving quality control and cost analysis as the most important reasons. CONCLUSION: The ASDI data set fitted existing needs very closely. Only 7 out of 122 parameters (5.7%) were found to be superfluous and thus removed. Measures to reduce documentation effort to the default limits were a) a new, date orientated concept for manual recording, b) rede-sign of the user interface with new, user friendly data entry possibilities, and c) the integration of statistical analysis and reports in the documentation system. The revised data set represents a broad-based consensus, which seems to be well-suited as foundation for the national quality assurance program.

Adolescent↗
PubMed1997

Supraclavicular approach to the subclavian/innominate vein for large-bore central venous catheters.

Infraclavicular and internal jugular catheterization are commonly used techniques for hemodialysis access, but may at times be impeded in patients whose anatomy makes cannulation difficult. In an effort to enlarge the spectrum of alternative access sites, we evaluated the supraclavicular approach for large-bore catheters. During an 18-month period we prospectively collected data on success rate and major and minor complications of the supraclavicular access for conventional dialysis catheters as well as Dacron-cuffed tunneled devices in 175 adult patients admitted for various extracorporeal therapies and bone marrow transplantation. Two hundred eight large-bore catheters (99 conventional dialysis catheters, 63 semirigid tunneled Dacron-cuffed catheters, and 46 Hickman catheters) were successfully placed in 164 patients (success rate, 93.8%), 58 (33.1%) of whom had been previously catheterized. Complications included pneumothorax (one patient), arterial puncture (seven patients), and puncture of the thoracic duct (two patients) without sequelae. Postinsertional chest radiographs demonstrated impressive coaxial lie of most catheters. Catheter malpositions occurred only sporadically (1%). Difficulty of introducing the catheter via a placed sheath was rarely observed. There was no clinically significant evidence of catheter-induced venous thrombosis or stenosis. We conclude that the supraclavicular route is an easy and safe first approach for large-bore catheters, as well as a useful alternative to traditional puncture sites for precatheterized and anatomically problematic patients.

Adolescent↗
PubMed1997

Myocardial revascularization without cardiopulmonary bypass in pigs: a comparison between beta-blockers and Ca2+-channel blockers.

The purpose of this study was to develop the surgical technique for internal mammary artery grafting on the beating heart. In 10 pigs, heart rate was reduced with esmolol (n = 5) or verapamil (n = 5). In addition, the anti-ischaemic and anti-arrhythmic potencies of these drugs were investigated. Haemodynamics, mechanical function and ischaemia-sensitive laboratory measurements were assessed perioperatively. There were no differences in pre-ischaemic data including ischaemic clamping time of the left anterior descending artery. At the end of ischaemia haemodynamic parameters were significantly lower in the esmolol-group (P < 0.05). In the verapamil-group, one pig died from ventricular fibrillation during ischaemia, and one showed fibrillation during reperfusion (P < 0.01). There were no differences in cardiac function or enzymes between the groups. Reduction of heart rate was provided by both drugs, but no conclusive evidence was provided with regard to additional anti-ischaemic and anti-arrhythmic protection.

Adrenergic beta-Antagonists↗
PubMed1997

Nitric oxide concentration in the gas phase of the gastrointestinal tract in man.

Nitric oxide (NO) has been implicated in various aspects of physiological regulation in the gastrointestinal tract. Hence, measurement of luminal NO concentrations is of interest for studying physiological and pathophysiological alterations in NO generation; however, at present, no reliable measurement techniques are available. Here we describe novel approaches for measurement of NO concentrations directly in the gas phase of the stomach and colon in healthy subjects and patients. Studies were conducted in young healthy volunteers (n = 13), intensive care patients (n = 8) and patients undergoing gastroscopy (n = 8) or colonoscopy (n = 8). NO concentrations were measured by chemolumininescence detection in air obtained through a nasogastric tube, after inflation into the stomach of a defined volume of air, or directly in the air suctioned from the endoscope. The mean NO concentration obtained from the stomach of healthy volunteers studied under baseline conditions was 18.0 +/- 2.8 (SEM) p.p.m. Day-to-day reproducibility of NO measurements was high. Tube feeding with a nitrite- and nitrate-free feeding solution left gastric NO concentrations unchanged, but standardized bicycle exercise caused an approximately 30% decrease in NO levels. NO concentrations in intensive care patients were approximately 2 log cycles lower than in healthy volunteers. NO levels in the colon were similar to those in the stomach. We have described two readily applicable techniques for direct, uncontaminated measurement of NO concentrations in the lumen of the gastrointestinal tract. Our finding of a striking reduction in gastric NO concentrations in intensive care patients requires further study.

Adult↗
PubMed1997

Measurement of right ventricular performance during apnea in patients with acute lung injury.

BACKGROUND: Mechanical ventilation resulted in increased, decreased or unchanged end-diastolic volumes together with either profoundly decreased or unchanged right ventricular ejection fraction (RVEF). The goal of our study was, therefore, to evaluate the effects of positive end-expiratory pressure on measurements of RVEF performed during apneic periods with different levels of positive end-expiratory pressure. METHODS: Fifteen consecutive patients suffering from acute lung injury after major surgery or trauma were included. Measurements were performed during 15 seconds of apnea at airway pressure levels of 0 (baseline), 10, 20, and 30 cm H2O. Cardiac output and RVEF were determined using the thermodilution technique. RESULTS: Lung inflation to an airway pressure of 30 cm H2O caused a 22 +/- 14% decrease of cardiac output resulting from a 20 +/- 14% decrease of stroke volume index. The decrease of stroke volume index was induced by a 17 +/- 11% decrease of right ventricular end-diastolic volume index, while RVEF remained virtually unchanged (0.49 +/- 0.10 vs. 0.47 +/- 0.12 at 0 and 30 cm H2O, respectively). Relative changes of cardiac output were closely correlated with changes of right ventricular end-diastolic volume index (p < 0.05, r2 = 0.78). CONCLUSIONS: Right ventricular systolic function was well maintained despite substantially decreased end-diastolic volumes. In our study, during apneic conditions, higher levels of positive end-expiratory pressure did not worsen RVEF in patients with acute lung injury. The proposed technique of apneic lung inflation may serve as an alternative approach to obtain comparable measurements of RV function in patients with acute lung injury.

Abdomen↗
PubMed1997

The contribution of extracranial blood oxygenation on near-infrared spectroscopy during carotid thrombendarterectomy.

To determine the contribution of extracranial oxygenation on regional cerebral oxygenation measured by an Invos 3100 near-infrared spectrometer, we measured oxygenation in blood drawn from both the facial vein (draining substantially blood from forehead areas) and the jugular venous bulb. There was no correlation between regional cerebral oxygenation and facial vein oxygenation (p = 0.35) but there was a significant correlation between regional cerebral oxygenation and jugular venous bulb oxygenation (p = 0.027). Linear regression analysis predicted a 3.6% change in regional oxygenation for every 10% change in jugular venous bulb oxygenation. We showed that extracranial tissue oxygenation had a negligible influence on the values recorded using near-infrared spectroscopy. Individual changes in jugular venous bulb oxygenation were poorly reflected. Data obtained by this near-infrared spectroscopy device are an unreliable guide to the adequacy of cerebral oxygenation.

Adult↗
PubMed1997

Prospective randomized comparison of cefodizime versus cefuroxime for perioperative prophylaxis in patients undergoing coronary artery bypass grafting.

The effects of cefodizime and cefuroxime on neutrophil phagocytosis and reactive oxygen production in 54 patients undergoing elective coronary artery bypass grafting were studied. Both drugs were administered twice at a dosage of 40 mg/kg of body weight (pre- and intraoperative). Phagocytic capacity was assessed by measuring the uptake of fluorescein isothiocyanate-labeled Escherichia coli and Staphylococcus aureus by flow cytometry. Reactive oxygen generation after phagocytosis was estimated by determining the amount of dihydrorhodamine 123 converted to rhodamine 123 intracellularly. In both groups the mean phagocytic ability for E. coli and S. aureus decreased during surgery (-21 and -8%, respectively, for the cefodizime group and -39 and -38%, respectively, for the cefuroxime group; P < 0.05 for all). In the cefodizime group a normalization of mean E. coli and S. aureus neutrophil phagocytosis was seen on day 5 (+9 and -4% compared to preoperative values; P > 0.35 for both), whereas in cefuroxime-treated patients phagocytic ability remained depressed (-37 and -31%; P < 0.04 for both). In both groups mean neutrophil reactive oxygen intermediate (ROI) production after E. coli and S. aureus phagocytosis increased during cardiopulmonary bypass (+44 and +83%, respectively, in the cefodizime group and +58 and +73%, respectively, in the cefuroxime group; P < 0.05 for all). One day after surgery E. coli- and S. aureus-driven neutrophil ROI production was not different from the preoperative values (-2 and +12%, respectively, for the cefodizime group and +7 and +15%, respectively, for the cefuroxime group; P > 0.15 for all). Postoperative serum levels of the C-reactive protein on days 2 and 7 were lower in cefodizime-treated patients (19 +/- 6 and 4 +/- 2 mg/liter versus 23 +/- 6 and 11 +/- 5 mg/liter; P < 0.05 for both). In addition to cefodizime's antimicrobial activity during perioperative prophylaxis, its use in coronary artery bypass grafting can prevent procedure-related prolonged postoperative neutrophil phagocytosis impairment.

Aged↗
PubMed1996

Early onset of pulmonary mucormycosis with pulmonary vein thrombosis in a heart transplant recipient.

Pulmonary infections are major complications in heart transplantation. Progress in antimicrobial chemotherapy has switched the clinical spectrum to an increased incidence of fungal pathogens, such as Candida and Aspergillus species. Mucormycosis is a rare opportunistic infection with high mortality in solid-organ transplant recipients usually ensuing several months after transplantation. We describe a 45-year-old patient with pulmonary mucormycosis manifestion 5 days after heart transplantation. The infection resulted in pulmonary vein thrombosis followed by hemorrhagic infarction. Despite antifungal treatment and surgical resection, the patient died on day 14 after transplantation. Antemortem diagnostic procedures were negative; autopsy confirmed the presence of Rhizopus oryzae invading blood vessels. We conclude that physicians must be aware of mucormycosis even within one week after heart transplantation--which has not been described so far. Invasive diagnostic workup is mandatory in case of suspicion; amphotericin B and, in selected cases, surgical resection are the mainstays of therapy.

Heart Transplantation↗
PubMed1996

Nutritional status, ICU duration and ICU mortality in lung transplant recipients.

OBJECTIVE: To determine the relation of malnutrition and underlying diagnosis to the length of stay in the Intensive Care Unit (ICU) and to mortality after lung transplantation (LTX). DESIGN: Retrospective ICU chart review. SETTING: Cardiothoracic ICU in a University hospital. PATIENTS: Fifty-one consecutive patients who suffered from end-stage lung disease from April 1992 to January 1994. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: The median time spent in the ICU was 5 days (range, 2-123 days). Patients with an underlying diagnosis of obstructive lung disease had significantly shorter ICU stays (median 4 days; range, 2-28 days) than those with restrictive lung disease (median 7 days; range, 2-123 days) (p = 0.005) or pulmonary hypertension (median 10 days' range, 2-38 days) (p = 0.041). Significant differences in ICU duration were observed between patients after double lung transplantation (median 10 days; range, 2-123 days) and those after single lung transplantation (median 4 days; range, 2-36 days) (p = 0.004). No statistically significant difference in ICU duration was found between patients with different nutritional statuses. In those patients who could not be discharged from the ICU before the 5th day, a body mass index (BMI) below the 25th percentile was a statistically significant risk factor for ICU mortality (p = 0.05). CONCLUSIONS: We conclude that the type of transplant procedure and the underlying diagnosis are important predictive indicators of ICU duration. A poor nutritional status (BMI below the 25th percentile) is a risk factor for ICU mortality in cases of patients who stay for 5 days or longer in the ICU.

Adolescent↗
PubMed1996

Effects of endotoxin infusion on mean systemic filling pressure and flow resistance to venous return.

Mean systemic filling pressure (Psf) is an indicator of the filling state of the systemic circulation. Cardiac output (Q') is related linearly to the difference between Psf and central venous pressure (Pcv), according to: Q' = (Psf - Pcv)/Rsf, where Rsf is the flow resistance downstream from the sites where blood pressure is equal to Psf. In 16 anaesthetized pigs we evaluated Psf, Rsf and Q' during baseline conditions, continuous endotoxin infusion and after subsequent fluid loading. Psf and Rsf were determined from simultaneous measurements of Q' and Pcv at seven levels of lung inflation. The following results were obtained. Psf was 8.1 +/- 1.8 mm Hg (mean +/- SD) during baseline conditions, increased after endotoxin infusion to 9.9 +/- 3.2 mm Hg (P = 0.04) and remained the same after infusion of 18 ml kg-1 of Ringer s lactate. Rsf increased from 0.34 +/- 0.07 to 0.80 +/- 0.34 mm Hg ml-1 s by endotoxin and decreased after fluid infusion to 0.58 +/- 0.14. Q' changed inversely proportional to Rsf (P = 0.001). Rsf changes were highly correlated with the changes in total systemic flow resistance (Rs) (P < 0.001). Endotoxin caused haemoconcentration and a decrease in plasma volume. The stability of Psf during endotoxin infusion and after volume loading indicate that the stressed volume was well maintained and changes in blood volume are compensated by changes in non-stressed volume. The increase in Rsf can be attributed to arteriolar vasoconstriction, venous vasoconstriction and haemoconcentration.

Animals↗
PubMed1996

Human growth hormone kinetics in critically ill patients.

Several studies have shown that exogenous human growth hormone (HGH) exerts an anabolic effect on protein metabolism in surgical patients with mild or moderate catabolism. However, contradictory results have been demonstrated in polytrauma patients where HGH did not improve protein metabolism. Aim of this study was to evaluate whether the pharmacokinetics of recombinant biosynthetic human GH (r-HGH) are altered in critically ill patients. After an overnight fast, r-HGH was infused at a rate of 460 micrograms/h/kg/bw during 120 min to five intensive care unit (ICU) patients. The patients were catabolic (nitrogen balance -11 +/- 0.5), showed normal liver function, and only one patient had a slightly impaired kidney function (creatinine > 1.5 mg/dl). Endogenous GH secretion was suppressed by continuous infusion of 50 micrograms/m2/h somatostatin. From plasma GH curves, elimination half life (t1/2kle), whole body clearance (Cltot) and steady state distribution space (DS) were calculated in an open two compartment model. Additionally, the effects of r-HGH infusion on plasma insulin, glucagon and amino acid concentrations were evaluated. T1/2kle was 19.6 +/- 2.3 min, Cltot 2.9 +/- 0.4 ml/kg/bw/min and DS 76.4 +/- 3.8 ml/kg/bw for 90 min. The plasma levels of total amino acids including the branched chain amino acids valine, leucine and isoleucine and of glutamine were significantly higher during r-HGH infusion than during the basal and somatostatin periods. In conclusion, the elimination of r-HGH in catabolic ICU patients is not different from that of healthy volunteers.

Adult↗
PubMed1996

Tailoring of the lung to overcome size disparities in lung transplantation.

BACKGROUND: Between October 1989 and December 1994 in 13 (four single and nine bilateral lung transplantations) of 124 lung transplantations, pulmonary allografts were considered to be too large to fit into the recipient thoracic cavity. METHODS: In all these patients (emphysema n = 6, fibrosis n = 4, pulmonary hypertension n = 3), the transplanted lungs were trimmed by extra anatomic wedge resections with the use of mechanical stapling devices to reach an acceptable size. RESULTS: No postoperative complication attributable to the tailoring procedure was observed. CONCLUSIONS: Tailoring of the lung is a safe and efficient method to overcome moderate size disparities between donor and recipient lungs.

Humans↗