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H Metzler

Publications and source records attributed to H Metzler.

At least 37 records · Page 2Linked to original sources
PubMed2000

Perioperative myocardial cell injury: the relationship between troponin T and cortisol.

STUDY OBJECTIVE: To investigate whether there is an association between Troponin T (TnT), reflecting myocardial cell injury, and cortisol, reflecting the degree of surgical trauma and associated stress, in light of our recent evaluation of TnT as a marker of perioperative myocardial cell injury. DESIGN: Prospective, cohort study. PATIENTS: 70 patients (67.4 +/- 8.7 yrs) with definite or at-risk coronary artery disease (CAD) undergoing elective noncardiac surgery (vascular n = 38, abdominal n = 21, orthopedic n = 8) with general (n = 63) or regional (n = 4) anesthesia with postoperative on-demand analgesia. MEASUREMENTS AND MAIN RESULTS: Morning blood samples for TnT (upper limit of normal: <0.2 ng/mL), CK-MB (reference range </=12 U/L), and cortisol (normal morning range 7-25 mcg/dL) were taken on the day before surgery, on the morning of surgery before induction of anesthesia, and on the first 5 postoperative days. Data were compared by analysis of variance. Three patients were excluded from the study because of incomplete blood samples of TnT or cortisol. Preoperative mean cortisol levels (mcg/dL +/- SD) were within the normal range and equal in TnT positive (n = 13) and negative (n = 54) patients (16.1 +/- 4.5 vs. 15.6 +/- 5.8). On the 1st postoperative day, there was a substantial increase of cortisol in the TnT positive group (35.7 +/- 26.9). Cortisol remained high until the 5th postoperative day (24.7 +/- 9. 4). There was a significant difference in the cortisol concentration in TnT-positive compared to TnT-negative patients (p < 0.001), a significant difference in the perioperative cortisol concentration over time (p < 0.05), and a significant interaction (p < 0.001). But there was no consistent temporal relationship between the increase of TnT and the increase of cortisol. CONCLUSIONS: The significant relationship between a highly sensitive and specific marker of myocardial cell injury and a marker of stress suggests that cardiac-risk patients undergoing stressful surgical procedures might benefit from close perioperative TnT monitoring with early recognition of myocardial cell injury.

Aged↗
PubMed2000

Low potential of dobutamine and dopexamine to block intestinal peristalsis as compared with other catecholamines.

OBJECTIVE: Catecholamines are frequently used in critically ill patients to restore stable hemodynamics and to improve organ perfusion. One effect of short-term or long-term administration of catecholamines may be inhibition of propulsive motility in the intestine. We therefore analyzed the effect of dopexamine, dobutamine, and dopamine on ileal peristalsis and compared their action with that of epinephrine and norepinephrine, which have long been known to suppress intestinal peristalsis. DESIGN: In vitro study on excised guinea pig ileum segments. SETTING: Laboratory for experimental studies at the University. SUBJECTS: Isolated guinea pig ileum. INTERVENTIONS: Segments of ileum excised from guinea pigs were mounted in a tissue bath in Krebs-Henseleit solution and bubbled with 95% oxygen/5% CO2. Luminal perfusion with the same solution was performed at a rate of 0.35 mL/min. The bath temperature was kept at 36.5 degrees C. Peristalsis was recorded via changes in the intraluminal pressure. The drugs under investigation (dopamine, epinephrine, norepinephrine, dobutamine, and dopexamine) were added to the tissue bath. MEASUREMENTS AND MAIN RESULTS: Low concentrations of each catecholamine, except epinephrine, caused a decrease in the pressure threshold, which reflects a stimulatory effect on peristalsis. Higher catecholamine concentrations caused a concentration-related increase in the threshold, cumulating in a complete block of peristalsis. The rank order of inhibitory potency was epinephrine > norepinephrine > dopamine > dobutamine approximately dopexamine. Dobutamine and dopexamine were about 500-fold less active than epinephrine in suppressing peristalsis. CONCLUSIONS: This study shows that dobutamine and dopexamine have the least potential to block propulsive motility in the intestine, whereas epinephrine demonstrates the most adverse inhibitory effect. Because at low concentrations dobutamine and dopexamine even stimulate peristalsis, these drugs appear to be superior compared with other catecholamines with regard to their direct effects on intestinal motility.

Adrenergic beta-Agonists↗
PubMed1999

Perioperative catecholamine changes in cardiac risk patients.

BACKGROUND: It has previously been found that in cardiac risk patients undergoing non-cardiac surgery post-operative cardiac complications are correlated with high post-operative serum levels of troponin T (TNT) and troponin I (TNI). We investigated whether perioperative changes in the release of free (fCAs) and conjugated catecholamines (cCAs) correlate with the increased serum level of TN (TN upward arrow). MATERIALS AND METHODS: Plasma levels of CAs were determined in 28 patients at risk for or with definite coronary artery disease. Blood sampling was performed in the morning on the day before surgery, on the day of surgery before induction of anaesthesia and until the fifth post-operative day for measurement of CAs by high-performance liquid chromatography. RESULTS: The plasma concentrations of free and conjugated noradrenaline (fNA and cNA) as well as of free and conjugated adrenaline (fA and cA) were increased significantly in TN upward arrow patients post-operatively. The plasma levels of free as well as of conjugated NA and A in TN upward arrow patients were significantly higher than in TN0 patients over the whole post-operative period. CONCLUSION: This study demonstrates that increased post-operative release of fNA and fA as well as of cNA and cA correlates with high post-operative serum levels of troponins in cardiac risk patients undergoing non-cardiac surgery.

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PubMed1999

[Anesthesia monitoring: degree of compliance with guidelines in Austria].

PURPOSE: For the first time an evaluation of standard anesthetic monitoring was performed according to the guidelines of the Austrian Society for Anesthesiology, Resuscitation und Intensive Care Medicine (OGARI). METHODS: A questionnaire was delivered to all medical institutions performing anesthesia in Austria. A descriptive statistical evaluation was performed on all returned and completed questionnaires. RESULTS: Generally, there is a high standard in compulsory monitoring and in PACU (actual compliance > 99%/85.8%). Supplemental equipment is required for disconnection alarm and measurement of inspired oxygen concentration (actual compliance: 98.3%/98.9%). Furthermore, measurement for inspired concentration of volatile anesthetics and relaxometry (actual compliance 68.7%/47.3%) has yet to be completed. University departments and regional hospitals have comparable standards (82.2% vs. 79.6%). CONCLUSIONS: For the first time an Austrian-wide evaluation of anesthetic monitoring investigated the compliance with the 1992 recommendations of the Austrian Society of Anesthesiology, Resuscitation and Intensive Care Medicine. The data demonstrate that these recommendations including the anesthetic monitoring equipment have already been implemented to a high degree.

Anesthesia↗
PubMed1999

The influence of different strategies on clinical outcome in patients undergoing total cavopulmonary connection.

BACKGROUND: We report on results of a prospective clinical trial designed to demonstrate the influence of various strategies in "Total Cavopulmonary Connection" (TCPC) for palliative therapy of patients with "single ventricle" physiology. METHODS: From 1989 to 1997, a total of 47 patients (mean age 4.8 +/- 3.6 years) underwent definitive TCPC at our unit. 31 patients (66%) underwent one-stage TCPC, in 16 patients (34%) we performed a two-stage modified Fontan operation; 21 patients had central fenestration (4 mm). Inhalative NO therapy in the immediate postoperative period was adopted in 1993. RESULTS: Overall 5-year survival was 76.4%, after two-stage TCPC 87.5%, and 81.3% in patients undergoing fenestrated procedures. Two of three patients survived perioperative Fontan take-down. We lost 11 patients (nine early and two late deaths): three patients died primarily because of neurologic dysfunction and eight patients because of cardiac failures. Under perioperative NO therapy there was no early death. After a mean follow-up of 35.9 +/- 23.3 months, 76% of all patients were in NYHA I and 21 % in NYHA I-II. 89.7% had sinus rhythm. 42% of our patients suffered from temporary pleuropericardial effusions. CONCLUSIONS: Definitive palliation with TCPC achieves acceptable clinical results. Two-stage repair, fenestration, and postoperative inhalative NO therapy - each have a positive influence on early and long-term survival.

Administration, Inhalation↗
PubMed1998

Perioperative ventricular dysrhythmias in patients with structural heart disease undergoing noncardiac surgery.

UNLABELLED: Noncardiac surgical patients with preoperative ventricular dysrhythmias and structural heart disease may be at increased risk of adverse cardiac outcome. We evaluated how anesthesia and surgery affect the course of ventricular dysrhythmias (premature ventricular beats [PVB] and repetitive forms of ventricular beats [RFVB]: couplets and nonsustained ventricular tachycardia) noted preoperatively in patients with structural heart disease and whether the frequency of ventricular dysrhythmias affects cardiac outcome. In a prospective study, 70 patients scheduled for noncardiac surgery with structural heart disease and RFVB on preoperative Holter electrocardiogram were continuously monitored intraoperatively and for 3 days postoperatively. Holter tracings were analyzed for rhythm, medians of total PVB and RFVB per hour. Preoperative RFVB recurred intraoperatively in 35% and postoperatively in 87% of patients. There was a significant intra- and postoperative decrease of total PVB per hour (P < 0.05) and RFVB per hour (P < 0.01). Frequency of ventricular dysrhythmias in the five patients suffering adverse outcome (unstable angina, n = 1; congestive heart failure, n = 4) did not significantly differ from those with good outcome. We conclude that in noncardiac surgical patients with structural heart disease and RFVB, the frequency of ventricular dysrhythmias is not associated with adverse cardiac outcome. IMPLICATIONS: Using continuous electrocardiogram monitoring, we investigated whether the frequency of perioperative ventricular dysrhythmias independently affects outcome in patients with structural heart disease undergoing noncardiac surgery. The incidence of perioperative dysrhythmia in patients with an adverse outcome (8%) did not differ from those with a good outcome.

Adult↗
PubMed1998

A new high-resolution esophageal electrocardiography recording technique: an experimental approach for the detection of myocardial ischemia.

UNLABELLED: Criteria for ischemic changes in the esophageal electrocardiograph (E-ECG) have not been standardized and validated. The main goal of this study was to evaluate the experimental esophageal recording of myocardial ischemia and to assess the association between ST segment alternans in the E-ECG and ischemia. Experiments were performed on 18 anesthetized sheep with occlusion of a branch of the left anterior descending artery. The bipolar signals were recorded via an esophageal lead containing three chloridized silver electrodes. Electrical signals were amplified in a self-designed, battery-supported preamplifier (gain 1000, frequency range 0.01-2000 Hz, common mode rejection 140 dB, signal noise 5-7 microV p-p), then sent to a digital oscilloscope for display and to a pulse code-modulated recorder. Surface electrocardiography (S-ECG) data were also recorded. Ischemia E-ECG revealed homogenous ST segments without any beat-to-beat alternans. Two minutes after occlusion, 14 of 15 sheep (93%) showed repetitive beat-to-beat fluctuations within the ST segment on the E-ECG. Of the 15 sheep, 7 (47%) showed ischemia in the S-ECG (P < 0.01). For calculation of the dynamic changes in the ST segment in the E-ECG, the difference in the amplitudes of the ST segment of five successive beats to the next beat, performed for 200 consecutive beats, was calculated. The central tendency of the sum of these values before versus during ischemia was 2000 mV/ms versus 5000 mV/ms (Hodges-Lehmann point estimator) (95% confidence intervals 1700/2500 versus 3350/9250 [lower limit/upper limit]). The authors have established a close temporal relationship between the magnitude of ST segment alternans recorded via E-ECG and myocardial ischemia. IMPLICATIONS: The study presents the use of an esophageal electrocardiograph for detection of progressive changes of myocardial ischemia and infarction. During acute myocardial ischemia and infarction in sheep, the esophageal electrocardiograph has visually apparent ST alternans of amplitude in the millivolt range, in part due to a special amplifier (0.01-2000 Hz). This is therefore one very promising technique for better evaluation of electrocardiographic changes of ischemia.

Animals↗
PubMed1998

DA1-receptor stimulation by fenoldopam in the treatment of postcardiac surgical hypertension.

BACKGROUND: Besides adequate analgesia, sedation and ventilation, postcardiac surgical hypertension has to be treated frequently with vasoactive drugs to avoid possible complications. In this study the hemodynamic effects of the DA1-receptor agonist fenoldopam (F) are compared to those of the Ca-channel antagonist nifedipine (N). METHODS: Postoperatively, 64 CABG-patients with a mean arterial pressure (MAP) of more than 105 mmHg over 10 min were investigated. Patients with compromised ventricular function, insufficient surgical repair, arrhythmia or an ECG unable to detect myocardial ischemia were excluded. The study drugs (initial dosage: F: 0.8; N: 0.3 micrograms.kg-1.min-1) were given continuously via a central venous catheter to reduce and to maintain the MAP between 80 and 95 mmHg. Hemodynamic parameters were determined using thermodilution technique. RESULTS: A significant reduction of the MAP (F: from 121 +/- 11 to 83 +/- 4, N: from 119 +/- 8 to 82 +/- 9 mmHg) and of the calculated systemic vascular resistance (SVR) (F: 2110 +/- 500 to 970 +/- 200, N:1980 +/- 660 to 1020 +/- 300 dyn.s.cm-5) were noted in both groups, whereby in the F group the therapeutic goal could be achieved more quickly with the dosage regimen chosen. As a result, a marked increase of heart rate, cardiac index and stroke volume index could be observed, which was more pronounced due to the initially stronger decrease of SVR with F. There was also a stronger decrease of pulmonary vascular resistance in the F group, but the indices of right ventricular function did not differ between the groups. CONCLUSION: Fenoldopam seems to be an efficient alternative to nifedipine, especially because of its more rapid onset of action.

Antihypertensive Agents↗
PubMed1998

Inhaled nitric oxide in infants and children after open heart surgery.

OBJECTIVE: To assess the effects of inhaled nitric oxide (NO) on oxygenation and pulmonary circulation in infants and children with critical pulmonary perfusion and/or hypoxemia after open heart surgery. STUDY: A prospective case series report. SETTING: A multidisciplinary pediatric intensive care unit in a University hospital PATIENTS: From June 1993 to March 1996 37 pediatric patients after open heart surgery were treated with inhaled NO. Their mean age was 2.9+/-0.6 years, their mean body weight 12.6+/-1.8 kg. METHODS: Inhaled NO was applied using a microprocessor controlled delivery system which continuously measured NO and NO2 by the chemilumniscence method. Monitoring included ECG, continuous pulse oximetry (SaO2), arterial (AP), central venous (CVP) and left atrial (LAP) pressures and in 8 patients a pulmonary artery (PAP) pressure. Inhaled NO was started at an SaO2 <90% with a fraction of inspired oxygen concentration (FiO2) >0.7, at a mean pulmonary artery pressure (MPAP) >50% of the mean arterial pressure (MAP), and in patients after Fontan-procedure at a CVP-LAP pressure gradient >10 mmHg. RESULTS: The mean dose of inhaled NO was 3.7+/-0.3 ppm and the mean duration was 112+/-14.7 hours. For the whole group SaO2 increased from 79.6+/-2.3 to 90.1+/-1.5% (p<0.01) within 20 minutes of NO-inhalation. Inhaled NO significantly decreased the MPAP from 47.8+/-4 to 27.5+/-2.3 mmHg (p<0.01) in 8 patients with postoperative pulmonary hypertension and significantly decreased the transpulmonary pressure (CVP-LAP) from 14.3+/-0.8 to 7.3+/-0.9 mmHg (p<0.01) in 16 patients after Glenn- or Fontan-procedure. CONCLUSIONS: Inhaled NO is very effective to decrease pulmonary artery pressure, to improve oxygenation, and to improve Fontan-circulation in infants and children after open heart surgery.

Administration, Inhalation↗
PubMed1998

[Amalgam--a question of belief? A review and assessment of the current literature].

Several hundred written sources have been researched regarding old and new findings. Forgotten and new facts are covered in four chapters. One of the authors is a retired industrial chemist, and the other a dental surgeon. In the first section the natural and synthetic sources of mercury are explained. In every scientific study the ubiquity of mercury for billions of years must be taken into consideration. The second chapter looks at the toxicology of mercury and its compounds. Well known catastrophies in Japan and Iraq are depicted. Individual intoxications are hardly mentioned in literature. The third chapter is devoted to the dental amalgam, a silver alloy with both physical-chemical properties, and corrosive and thermal behaviour. An attempt is made to define the mercury balance. The forth paragraph deals with the disposal and recycling of mercury. Many dental associations are currently discussing the possibility of recycling amalgam, which is rather a stable silver alloy than a volatile mercury compound. A controlled landfill disposal of dental amalgam will absorb a certain quantity of mercury during its life cycle, and is positive. Recycling is expensive, energy consuming and causes additional exposure. Unless silver and mercury become rare metals, recycling should not be considered. As yet no worldwide regulatory procedures exist.

Chemical Phenomena↗
PubMed1997

Inhaled nitric oxide in patients with critical pulmonary perfusion after Fontan-type procedures and bidirectional Glenn anastomosis.

OBJECTIVE: The aim of this study was to evaluate the effects of inhaled nitric oxide in patients with critical pulmonary perfusion after Fontan-type procedures and bidirectional Glenn anastomosis. METHODS: Inhaled nitric oxide (mean 4.1 +/- 0.7 ppm, 1.5 to 10 ppm) was administered in 13 patients (mean age 5.6 +/- 1.6 years, 1.5 to 17 years) with critical pulmonary perfusion (central venous pressure > 20 mm Hg or transpulmonary pressure gradient > 10 mm Hg) in the early postoperative period after total cavopulmonary connection (n = 9) or after bidirectional Glenn anastomosis (n = 4). RESULTS: In patients after total cavopulmonary connection inhaled nitric oxide therapy decreased central venous pressure by 15.3% +/- 1.4% (p = 0.0001) and transpulmonary pressure gradient by 42% +/- 8% (p = 0.0008) and increased mean systemic arterial and left atrial pressures by 12% +/- 3.6% (p = 0.011) and 28% +/- 8% (p = 0.007), respectively. Arterial and venous oxygen saturations improved by 8.2% +/- 1% (p = 0.005) and 14% +/- 4.3% (p = 0.03), respectively. In patients after bidirectional Glenn anastomosis inhaled nitric oxide therapy resulted in a decrease of central venous pressure by 22% +/- 1% and of the transpulmonary pressure gradient by 55% +/- 6% and improved arterial and venous oxygen saturations by 37% +/- 29% and 11% +/- 3%, respectively. Mean systemic arterial and left atrial pressures remained nearly unchanged. No toxic side effect was observed in any patient. CONCLUSION: Inhaled nitric oxide may play an important role in the management of transient critical pulmonary perfusion caused by reactive elevated pulmonary vascular resistance in the early postoperative period after Fontan-type operations and bidirectional Glenn anastomosis.

Administration, Inhalation↗
PubMed1997

Perioperative myocardial cell injury: the role of troponins.

Early recognition of minor myocardial cell injury and appropriate treatment may prevent development of myocardial infarction as one of the most severe postoperative cardiac complications. Troponins have been shown to be sensitive biochemical markers for the assessment of myocardial cell injury. We investigated prospectively 67 cardiac risk patients undergoing elective non-cardiac surgery. Troponin T (TNT) concentrations were measured during the perioperative period, and in those patients with increased TNT (cut-off 0.2 ng ml-1), troponin I (TNI) concentrations were measured additionally (cut-off 0.6 ng ml-1). Patients were allocated to one of three groups: group I, all patients with normal TNT concentrations had a good cardiac outcome (80.5%). In those patients with increased TNT concentrations (19.5%) TNI was also positive; group II, patients (8.8%) with only slightly increased TNT concentrations (0.32-0.99 ng ml-1) also had a good outcome, indicating minor myocardial cell injury, whereas patients with cardiac complications (11.9%) had higher TNT concentrations (0.47-9.8 ng ml-1) (P < 0.05) (group III). With a TNT cut-off at 0.2 ng ml-1, the positive predictive value for adverse outcome was 61.5%; the negative predictive value was 100%. With a TNT cut-off at 0.6 ng ml-1, the positive predictive value for adverse outcome increased to 87.5%, but the negative predictive value was still high (98%). Most of the patients showed an increase in TNT content from the day of surgery until the third postoperative day. We conclude that serial troponin measurements during the perioperative period identify pre-, intra- and postoperative myocardial cell injury. The concentration of troponin T may reflect the degree of injury and help categorize the subsequent risk.

Aged↗