PubMed Health⌕ Search

Biomedical subjects

M Berner

Publications and source records attributed to M Berner.

47 records · Page 3Linked to original sources
PubMed1989

Effect of low dose dopamine on hemodynamic and renal function in children.

The purpose of the study was to investigate the effect of low doses of dopamine in children. Fourteen cases were studied after open heart surgery. Cardiac output and renal parameters were determined under baseline conditions and under continuous infusion of dopamine 2.5 and 5 micrograms/kg/min. During the control period cardiac index was 2.62 +/- 0.19 L/min/m2, renal plasma flow was decreased at 269 +/- 41 mL/min/1.73 m2, GFR was 86.6 +/- 9.2 mL/min/1.73 m2, and filtration fraction was elevated at 37.1 +/- 1.9%. Plasma concentration of aldosterone correlated with the filtration fraction. At 5 micrograms/kg/min dopamine increased significantly cardiac output, renal plasma flow, and to a lesser extent GFR, thus decreasing the filtration fraction. At 2.5 micrograms/kg/min dopamine, increased renal plasma flow only in patients older than 5 y and had no effect on the other parameters. The increase of cardiac output in response to dopamine was abolished by propranolol pretreatment. By contrast, the hemodynamic renal response to dopamine was not altered by beta-blockade. These results indicate that 5 micrograms/kg/min of dopamine could prevent renal failure after open heart surgery in children by increasing renal blood flow and attenuating renal compensatory mechanisms.

Adolescent↗
PubMed1989

[Iterative surgery in germ cell tumor].

Between 1979 and 1988, iterative surgery was performed on 13 patients for a germ-cell tumor. Apart from orchidectomy, surgery was not the first modality of treatment. On the other hand, 21 surgical procedures were performed for residual tumoral masses after chemotherapy or recurrences. In one third of the cases, only necrosis of fibrosis was resected. Out of 13 patients, 7 died of tumor; 6 are alive (3 with complete remission). Surgery is always indicated in stage IIA to IV nonseminomatous tumors in case of residual tumoral deposits after chemotherapy. For seminoma, surgery is carried out only for retroperitoneal residues larger than 3 cm in diameter. Surgery is also indicated for persistent pulmonary or mediastinal metastases following chemotherapy. Complete surgical excision of residual masses may be technically difficult but is of prime importance as combined chemotherapy and surgery doubles the complete remission rate in comparison to chemotherapy alone.

Combined Modality Therapy↗
PubMed1989

[Sleep obstructive apnea syndrome and temporomandibular ankylosis. Maxillofacial correction for adults and children].

Juvenile temporomandibular bony ankylosis may generate micro- and retroposition of the mandible. Collapse of the upper airway during sleep due to muscle atonia awakens the patient, leading to compensative diurnal hypersomnia. In severe cases, alveolar hypoventilation may result in anoxic seizure, sudden death or development of life threatening cor pulmonale. The corrective surgical procedure for adult is an anterior sagittal osteotomy and in the growing child, costochondral grafting is proposed. Pre- and post-operative polysomnograms with recording of oxygen saturation are objective measures of good surgical results.

Ankylosis↗
PubMed1989

Chronotropic and inotropic supports are both required to increase cardiac output early after corrective operations for tetralogy of Fallot.

To assess the respective roles of chonotropism, inotropism, and afterload reduction in increasing cardiac index early after corrective operations for tetralogy of Fallot, we measured vascular pressures and cardiac output and evaluated left ventricular dimension changes before and after a 35% rise in heart rate over baseline. This rise was induced by atrial pacing with intact atrioventricular conduction, isoproterenol, or atrial pacing together with dobutamine. With atrial pacing, left ventricular end-diastolic diameter decreased (38.7 +/- 4.3 to 34.2 +/- 5.6 mm, p less than 0.05), the shortening fraction (ratio of the difference between left ventricular end-diastolic and end-systolic diameters to left ventricular end-diastolic diameter) remained constant, and stroke volume index was reduced (28.8 +/- 4.5 to 19.7 +/- 4.6 ml/m2, p less than 0.05). As a result, cardiac index was left unchanged. When dobutamine was added as supplemental inotropic support, left ventricular end-diastolic diameter remained constant, shortening fraction increased (30% +/- 5.4% to 36% +/- 3.3%, p less than 0.05), and cardiac index rose significantly (3.04 +/- 0.61 to 4.18 +/- 0.85 L/min/m2, p less than 0.05). Heart rate acceleration with isoproterenol, combining chronotropism, positive inotropic support, and afterload reduction, slightly increased left ventricular end-diastolic diameter, significantly raised shortening fraction, and markedly enhanced cardiac index (3.03 +/- 0.55 to 4.9 +/- 1.09 L/min/m2). Atrial pacing with intact atrioventricular conduction, as an isolated chronotropic stimulus, is not suited to increase cardiac index early after operations for tetralogy of Fallot unless additional inotropic support is simultaneously provided.

Adolescent↗
PubMed1988

Propranolol treatment in children with tetralogy of Fallot alters the response to isoprenaline after surgical repair.

When propranolol is given to prevent hypoxaemic episodes in children with tetralogy of Fallot who are awaiting operation it is advisable to continue the treatment until shortly before the induction of anaesthesia. Because catecholamines are often required to maintain adequate cardiac output after surgical correction the effect of preoperative treatment with beta blockers on the response to isoprenaline after the operation was investigated in nine children given propranolol before operation and nine who were not. They were studied three and 24 hours after cardiopulmonary bypass. The haemodynamic response to increasing doses of infused isoprenaline was monitored. Immediately after cardiopulmonary bypass the response to isoprenaline was significantly blunted in the patients who had been given propranolol before operation. Their dose-response curve lay to the right of that for patients not given propranolol, and this indicates competitive inhibition. Propranolol concentrations in the blood and myocardium correlated significantly with the heart rate response to isoprenaline. Twenty four hours after operation the isoprenaline response was similar in both groups and concentrations of propranolol in the blood were minimal or undetectable. beta Blockers given up to the time of operation significantly altered the postoperative response to catecholamines.

Blood Pressure↗
PubMed1984

Hemodynamic effect of isoprenaline and dobutamine immediately after correction of tetralogy of Fallot. Relative importance of inotropic and chronotropic action in supporting cardiac output.

In order to compare the effect of isoprenaline and dobutamine immediately after correction of tetralogy of Fallot, 12 randomly selected patients were studied postoperatively. Left ventricular end-diastolic volume, measured preoperatively by means of left ventricular angiograms in eight patients, was decreased to a mean value of 58.6 +/- 5.5 ml/m2 (mean +/- standard error of the mean). Postoperatively, cardiac output was measured by thermodilution before, during, and after infusion of increasing doses of isoprenaline (0.05, 0.1, and 0.2 micrograms/kg/min) and dobutamine (2.5, 5, and 10 micrograms/kg/min) successively given in each patient. Simultaneously, central venous, left atrial, pulmonary arterial, and systemic arterial pressures were recorded. Cardiac index increased significantly in response to all three doses of isoprenaline. Dobutamine produced only a small increase which was not statistically significant. Stroke volume index did not vary significantly with either drug. Consequently, cardiac index was directly related to heart rate. Preload of the left ventricle as well as afterload was significantly reduced (p less than 0.01 and p less than 0.05, respectively) by isoprenaline but not by dobutamine. An increase in left ventricular work index per minute was found with both drugs; however, only with isoprenaline was the increased work accompanied by a significant increase in cardiac index. We conclude that patients with tetralogy of Fallot usually have a small left ventricle which, immediately after correction, reacts to catecholamines by only an insignificant increase in stroke volume index. Consequently, isoprenaline is more effective than dobutamine in raising cardiac index due to the increase in heart rate. Moreover, it decreases systemic vascular resistances and obviates the need for administration of a vasodilator.

Adolescent↗
PubMed1983

The hemodynamic effect of phentolamine and dobutamine after open-heart operations in children: influence of the underlying heart defect.

The hemodynamic effects of phentolamine alone and in combination with dobutamine were studied in the immediate postoperative period in two groups of children. Group 1 (N = 6; mean age, 152 months) had open-heart operation for acquired mitral valve disease. Group 2 (N = 6; mean age, 60 months) had intracardiac repair for tetralogy of Fallot. Before drug administration, cardiac index did not differ between groups, but patients with tetralogy of Fallot had a higher heart rate and smaller stroke volume index; systemic vascular resistance was high in both groups. With phentolamine (10 micrograms/kg/min), cardiac index and stroke volume index increased similarly in both groups (+ 13% for cardiac index in Group 1, +9% in Group 2), while systemic vascular resistance, pulmonary vascular resistance, and pulmonary wedge pressure decreased. When dobutamine (5 micrograms/kg/min) was added, there was a further increase in cardiac index in both groups, but it was greater in Group 1 (+17% vs +12%, p less than 0.01, compared with phentolamine alone; +33% vs +22%, p less than 0.01, compared with control). Systemic vascular resistance remained unchanged and heart rate increased in both groups, so that the left ventricular stroke work index increased. Although stroke volume index increased significantly with dobutamine in Group 1 (+11%, p less than 0.01), it remained unchanged in Group 2 (+3%, not significant). Thus in Group 2, dobutamine increased cardiac index only by increasing heart rate. This suggests that the relatively small, noncompliant left ventricle in patients with tetralogy of Fallot cannot further respond to inotropic drugs by increasing stroke volume index.

Adolescent↗
PubMed1976

Biofeedback training to overcome poststroke foot-drop.

The technique has exciting potential for elderly hemiplegic patients, even those who are confined to a nursing home. There are limiting factors, of course; the method is time-consuming and the initial outlay for equipment is high. But the rewards can be well worth the time, effort, and cost involved. The recovery potential of some geriatric patients after a cerebrovascular accident may seem bleak because of multiple disabilities, e.g., paralysis, delayed reflexes, aphasia. Fortunately, these disorders do not necessarily decree failure of biofeedback training. Neither does advanced age. The strongest component in success is motivation. A case in point is the 82 year old woman described here who had been hemiparetic for seven years. With biofeedback training, she gained--and maintained--muscle strength.

Aged↗