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Biomedical subjects

H H Scheld

Publications and source records attributed to H H Scheld.

At least 289 records · Page 16Linked to original sources
PubMed1988

Revascularization of the right coronary artery: influence on thermodilution right ventricular ejection fraction.

This study was designed in order to evaluate the influence of right coronary artery (RCA) disease and its revascularization on right heart performance monitored by measuring thermodilution right ventricular ejection fraction (RVEF). Forty patients undergoing elective aortocoronary bypass surgery were divided into two groups: group 1, with RCA revascularization, n=20; and group 2, without RCA disease or revascularization, n=20. RVEF was measured using a pulmonary arterial catheter mounted with a fast-response thermistor and a bedside microprocessor ejection fraction computer. The major finding of the study was that myocardial revascularization with extracorporeal circulation was followed by a decrease in RVEF which was significantly more pronounced in group 1 (-13.1%) in comparison to group 2 (-5.0%). RVEF gradually increased after bypass, but did not reach baseline values. By the first postoperative day, RVEF had reached baseline values again in group 1 and had increased beyond baseline values in group 2. Traditionally measured hemodynamic parameters could not be correlated with the course of RVEF, except for cardiac index. The present study further suggests that right-sided events may have clinical effects on left-sided function. Inadequate protection of the right heart, especially in patients with RCA stenosis, may result in depression of right ventricular myocardial performance, which can be monitored serially by measuring RVEF.

Blood Pressure↗
PubMed1988

Resection of a heart tumor using autotransplantation.

A 38 year old male patient presented with a cardiac tumor. Echocardiography and visualization of the left atrium revealed a large myxoma. Surgical resection of the tumor was performed with the aid of cardiopulmonary bypass. The extensive size of the tumor base and its localisation at the posterior left atrial wall made a conventional approach impossible. Therefore radical resection of the tumor was undertaken using autotransplantation. After a routine postoperative course, the patient was discharged on the twenty seventh hospital day.

Adult↗
PubMed1988

Primary cardiac tumors--clinical experiences and late results in 48 patients.

Between 1971 and 1987 48 patients (35 female and 13 male) underwent operations at the Department of Cardiovascular Surgery, Justus-Liebig-University Giessen, for primary cardiac tumors. The age of the patients ranged from 21 to 71 years. Clinical symptoms were congestive heart failure, cardiac murmurs and findings similar to mitral stenosis, chest pain, arrhythmias, arterial embolism, myocardial infarction and pericarditis. 39 of the tumors were benign and 9 were malignant. Diagnosis was confirmed by echocardiography and/or cineangiocardiography. The left atrium was most commonly involved, followed by the right atrium. Surgery was performed in all cases using cardiopulmonary bypass. Benign tumors were totally removed, including attachment to the atrial septum or the free wall. In one case the tumor resection was carried out by autotransplantation of the heart. During the perioperative period we lost one of the 39 patients with benign tumors due to low cardiac output. Observing a mean follow up period of 48 months, no recurrence of tumors was noted and all patients are doing well now. The malignant neoplasms could not be removed completely, and in 4 cases only a reduction of the tumor mass was possible. Three of the 9 patients died during the postoperative period. Only one patient survived longer than 48 months. Whereas surgical therapy of malignant cardiac tumors is still a matter of discussion based upon these discouraging results, benign or semimalignant cardiac neoplasms have a very favourable prognosis when the surgical intervention can be performed prior to the occurrence of severe complications, such as congestive heart failure and arterial embolism.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Aortic arch replacement by posterolateral exposure.

Aortic arch replacement was carried out in a 54 year old male patient with an unexpected type A-dissection, using partial femoro-femoral bypass and hypothermic arrest, through a left side posterolateral thoracotomy. After the replacement of the aortic arch from the ascending to the descending aorta a warm-up perfusion was done through an 8 mm side arm Dacron prosthesis attached to the descending segment of the 30 mm Dacron graft. This technique was demonstrated to be safe and protective in our patient and can be used as an alternative surgical method in the treatment of aortic arch dissection or aneurysms of the transverse aortic arch.

Aortic Dissection↗
PubMed1988

Laser application in bronchology.

The use of laser in bronchology plays a major role in the therapy of benign and malignant tumours. By flexible delivery systems, lasers can be used in combination with flexible bronchoscopes. By this benign tumours, especially in young children, can be ablated successfully without major surgical intervention. In malignant tumours laser ablation can only be used as a palliative procedure in cases untreatable by conventional surgery or prior to radiation or chemotherapy, in which the symptoms of hemopthysis or significant obstruction are indications for an urgent treatment. Especially in elder patients a quick relief of symptoms can be reached avoiding the high risks of an operation. A new and experimental field of laser application in bronchology is the tracheal reconstruction with laser assistance. In 10 Beagle dogs laser assisted tracheal anastomoses revealed good functional results with an uneventful postoperative course. Histology showed a normal healing and a good reconstruction of the ciliated endothelium without metaplastic changes. So this new technique may in future become an additional tool in the reconstructive surgery of the trachea and main bronchi.

Animals↗
PubMed1988

[Enoximone, a new phosphodiesterase inhibitor: the spectrum of applications during heart surgery--a comparison with dobutamine].

During cardiac surgery treatment of deterioration of myocardial function is usually based on catecholamines. Development of selective phosphodiesterase-(PDE-)III-inhibitors seems to be a new aspect in treating myocardial dysfunction. Therefore the hemodynamic effects of the new PDE-inhibitor enoximone were investigated in 20 coronary surgery patients unable to be weaned from extracorporeal circulation (ECC) without pharmacological intervention (MAP less than 60 mmHg, CI less than 2.00 l/min.m2, PCP greater than 15 mmHg). After controlled reperfusion with 2.4 1/min.m2 two groups were separated in a random sequence receiving either 0.5 mg/kg enoximone as a bolus (n = 10), or dobutamine (n = 10, 5 micrograms/kg.min) as perfusion. In the dobutamine-group MAP and CI (-14%) were decreased, while HR was increased significantly (+30%). Application of enoximone was followed by a slight increase in CI (+5%), a significant decrease in TSR while HR remained almost unchanged. PCP, too, differed significantly between the groups (enoximone: -38%; dobutamine: -10%). Ten minutes after weaning from ECC additional pharmacologic therapy (calcium, vasodilators, epinephrine) was necessary in eight dobutamine treated patients in contrast to four patients in the enoximone group (calcium, epinephrine). In patients with impaired myocardial performance during weaning from ECC enoximone seems to be an alternative therapy and is judged to be of some advantage compared to dobutamine application in this situation. The mechanism for improvement appears to be enhanced contractility owing to its positive inotropic effects, as well as a decrease in left ventricular outflow resistance resulting from peripheral vasodilation.

Aged↗
PubMed1988

[Resuscitation and extravascular lung fluid in cardiac surgery].

Cardiovascular arrest may be followed by severe respiratory insufficiency due to an increase in the pressure in the pulmonary vascular system, an alteration in capillary permeability, or both. Extracorporeal circulation (ECC), on the other hand, can lead to a change in capillary integrity ('capillary leakage') caused by the unphysiologic perfusion patterns and/or activation of various mediator systems. Pulmonary hyperhydration (increased extravascular lung water [EVLW]) seems to be the most important factor limiting pulmonary function in this situation. This retrospective study was designed to investigate the influence of resuscitation in the period before ECC on pulmonary EVLW thereafter. Eight coronary surgery patients who had to be resuscitated in the period before the start of ECC due to cardiocirculatory arrest were compared to 8 patients without resuscitation selected randomly (control group). There were no differences between the two groups with regard to age, catheterization data, and ECC conditions. All patients underwent identical monitoring, including estimation of EVLW. Lung water measurement was performed by the thermal dye technique with indocyanine green (= non-diffusible indicator) dissolved in ice-cold dextrose (= diffusible indicator) and a bedside microprocessor before resusciation and after ECC (15 min, 45 min, 5h). Simultaneously, hemodynamics and parameters of pulmonary gas exchange were monitored. Baseline values of EVLW were comparable in both groups. After ECC a transient increase in EVLW could be demonstrated in the controls, indicating an altered fluid flux even in 'uncomplicated' courses; 5 h after ECC lung water content had again reached baseline values. In contrast, there was a significant increase in EVLW in the 'complicated group' immediately after ECC (+2.60 ml/kg) and 5 h after ECC (+1.38 ml/kg); in consequence, the paO2 was significantly decreased (-180 mmHg) while Qs/Qt was increased (+6.79%). It is concluded that the combination of two factors that potentially damage pulmonary tissue and increase lung water content (reanimation due to circulatory arrest and extracorporeal circulation) lead to a significant increase in extravascular lung water combined with a deterioration of pulmonary function, resulting in severe respiratory failure.

Capillary Permeability↗
PubMed1987

[Combination autotransfusion in heart surgery. Use of acute normovolemic hemodilution in coronary heart disease].

Normovolemic hemodilution (15 mg/kg body-weight: group I) was undertaken in 100 patients immediately before the start of coronary-artery surgery. In addition, a Cell-Saver (Haemonetics, Munich) was used for intra-operative autotransfusion. Another group of 100 patients (group II) was similarly operated on without autotransfusion (the study was conducted on 200 consecutive patients undergoing aorto-coronary bypass). Before blood (autologous or homologous) was administered a reduction of hemoglobin to 9 g/100 ml and hematocrit to 0.28 was well tolerated (during extracorporeal circulation: 6.5 g/100 ml and 0.16, respectively). Due to intra- and postoperative complications, such as infarct bleeding (including reoperation) or septicemia, the number of patients placed in group I fell to 94, that in group II to 90. Acute normovolemic hemodilution increased cardiac output and oxygen transport capacity, while other hemodynamic parameters remained unchanged, and there was no effect on extravascular lung water. Autotransfusion reduced the need for homologous blood derivatives by 71% (fresh blood, fresh plasma, RBC concentrates). No clinically significant disadvantages occurred.

Adult↗
PubMed1987

Influence of cardiac output on thermal-dye extravascular lung water (EVLW) in cardiac patients.

The influence of varying cardiac output (CO) on thermal-dye extravascular lung water (EVLW) was investigated in a total of 40 cardiac surgery patients before the onset of the operation. EVLW was measured by means of the double indicator dilution technique with indocyanine green as the non-diffusible indicator and a microprocessed lung water computer 15 min and 30 min after change of CO. CO was varied from -45% to +70% of the baseline value by nifedipine infusion (CO increases, n = 20) or halothane application (CO decreases, n = 20), respectively. CO was measured from the femoral artery instream thermistor tipped lung water catheter and, simultaneously, from the pulmonary artery. In spite of a highly significant decrease (-45%) and increase (+70%) in CO no change in EVLW could be observed. CO estimation was comparable for both methods used. Regression analysis revealed no relationship between CO and EVLW as well as between EVLW and various hemodynamic parameters. We conclude that thermal-dye technique for estimation of EVLW may be accurate in spite of changing cardiac output over a wide range.

Cardiac Output↗
PubMed1987

Extravascular lung water and hemofiltration during complicated cardiac surgery.

Hemofiltration (HF) is an established method for treating patients with impaired renal function and excessive fluid retention. In cardiac surgery fluid accumulation during extracorporeal circulation (ECC) may contribute to postoperative organ dysfunction, leading to severe pulmonary insufficiency. In this study our experiences with hemofiltration installed in the cardiopulmonary bypass are demonstrated in patients with preoperative pulmonary edema, impaired renal function, and long-term ECC, proving its efficacy by measurement of extravascular lung water (EVLW) in the early post-bypass period. EVLW-measurement was performed using the thermal-dye technique with indocyanine green and a microprocessed lung water computer. Our data demonstrate that hemofiltration during ECC is a valuable method for controlling fluid balance. It facilitates the intra- and postoperative management of patients with end-stage renal failure or with preoperative pulmonary edema. HF seems to be helpful by decreasing the risk of complications such as fluid overload, which is demonstrated by measurement of EVLW.

Blood↗
PubMed1987

Laser-assisted trachea anastomoses in dogs.

Tracheal anastomoses are known to be related to special surgical risks. We performed laser-assisted trachea anastomoses in 10 Beagle dogs, using an Argon-laser system and a handheld quarz fiber for energy transmission. All animals showed an uneventful postoperative course without signs of infection, air-leakage or respiratory impairment. Pathologic examination revealed no significant stenosis but a normal reconstruction of the tracheal endothelium and a normal woundhealing with only an increased connective tissue reaction. Because of the lower tensile strength of laser-assisted anastomoses in general, three adapting absorbable sutures should be left in situ to increase the resistance against mechanical stress. Under these circumstances laser-assisted anastomoses seem to be a promising additional method in the field of tracheal reconstruction and transplantation.

Anastomosis, Surgical↗
PubMed1987

[Modified substitution of intracellular cations].

In order to ascertain the effect of modified supplementation of electrolytes and trace metals on intracellular uptake, 75 patients undergoing mitral valve replacement were randomly divided into three groups: group A (n = 25) received potassium and sodium chloride while group B (n = 25) was treated with potassium aspartate; in group C (n = 25), a balanced solution of electrolytes and trace metals (Inzolen) with aspartate as the anion was given. The treatment in the three groups was administered on the basis of frequently measured plasma levels of potassium and sodium. Anesthesia was similar in all patients; cardiac arrest was performed by crossclamping of the aorta using "Bretschneider's cardioplegia" for sodium withdrawal. After removal of the mitral valve, a sample of papillary muscle was obtained and analyzed by atomic absorption for its content of sodium, potassium, magnesium, zinc, and copper (Na, K, Mg, Zn, Cu). Sodium levels in papillary tissue were below the normal range in all groups and without differences depending upon the kind of treatment. Potassium levels in group A, however, (KCl) were markedly below those in groups B and C (aspartates). A similar effect could be observed with respect to tissue levels of Mg, Zn, and Cu. Supplementation of trace metals (group C) had no additional effect on tissue concentrations: there were no significant differences between group B (K aspartate) and group C (K-, Mg-, Zn-, Cu-, Na aspartate). Our results stress the importance of effective treatment of electrolyte and trace metal deficiencies. The present data suggest that the utilization of intracellular cations can particularly be improved by using solutions with aspartate as the anion.

Adult↗