PubMed Health⌕ Search

Biomedical subjects

R K Klocke

Publications and source records attributed to R K Klocke.

15 recordsLinked to original sources
PubMed1994

Simultaneous measurement of cardiac output by thermodilution, thoracic electrical bioimpedance and Doppler ultrasound.

To evaluate the accuracy of two non-invasive techniques for cardiac output (CO) measurement, we have measured CO simultaneously by thoracic electrical bioimpedance (TEB), pulsed Doppler ultrasound (DU) and standard thermodilution methods (TD) under different clinical conditions. Measurements were made in 10 patients: (I) during steady state anaesthesia with controlled IPPV ventilation (n = 131), spread over the entire ventilatory cycle; (II) during apnoea (n = 56); (III) during spontaneous breathing (n = 152) in the intensive care unit. Mean (SD) cardiac output values were: (I) COTD 3.5 (1.0) litre min-1, COTEB 3.4 (0.7) litre min-1, CODU 2.8 (0.7) litre min-1; (II) COTD 3.6 (0.6) litre min-1, COTEB 3.5 (0.4) litre min-1, CODU 2.9 (0.7) litre min-1; (III) COTD 7.7 (1.5) litre min-1, COTEB 7.6 (1.9) litre min-1, CODU 5.2 (1.4) litre min-1. The mean percentage deviation of TEB from TD ranged from -2.2% to 1.4% and that of DU from TD was from -16% to -32%. There were no statistically significant differences between TD and TEB, but TD and DU differed significantly during IPPV, apnoea and spontaneous ventilation (P < 0.0001).

Adult↗
PubMed1992

[The place of thoracic plain film in the assessment of left heart insufficiency].

The chest radiographs of 24 patients with chronic left heart failure (mean duration of cardiac disease 4.3 years) were compared with the haemodynamic findings. Before the initiation of intensive medical treatment haemodynamic parameters were measured invasively and followed up for a period of up to 16 months. The heart size and roentgenographic patterns of pulmonary congestion showed a weak negative correlation with both the ejection fraction and the cardiac index. During therapy changes of cardiopulmonary haemodynamics did not correlate with alterations of the radiographic findings. Therefore chest radiographs are not useful in the assessment of the therapeutic success in long-existing left heart failure; nevertheless, they are indicated to identify secondary pulmonary disease.

Adult↗
PubMed1991

Effects of a twenty-four-hour milrinone infusion in patients with severe heart failure and cardiogenic shock as a function of the hemodynamic initial condition.

The systemic and pulmonary arterial hemodynamics of 40 patients with severe congestive heart failure were determined during a 24-hour infusion of milrinone (0.5 micrograms/kg/min) after a loading dose of 50 micrograms/kg. A subgroup (n = 18) with severe cardiac pump dysfunction and three patients in cardiogenic shock were analyzed separately; their hemodynamic response was compared with that of the total group (n = 40). After 15 minutes of intravenous therapy with milrinone, the total group (n = 40) showed an increase of 65% in cardiac index; in the subgroup (n = 18) cardiac index increased by 94% after 15 minutes and by 106% after 30 minutes. Likewise, pulmonary capillary wedge pressure decreased after 30 minutes in both the total group (n = 40) and the subgroup (n = 18). The heart rate showed an overall tendency to decrease. The systolic blood pressure tended upward and remained statistically unchanged in the total group, whereas in the subgroup in which pressure was initially low, there was an increase in the systolic pressure after 1 hour and a further increase after 24 hours. Mean arterial pressure also rose in this subgroup. The early improvement in all measured hemodynamic parameters was sustained throughout the 24-hour infusion period. Development of tolerance was not observed, nor were any clinically symptomatic side effects or symptomatic arrhythmias. Thus intravenous milrinone is a safe medication for the rapid and prolonged improvement in hemodynamics, specifically in patients with severely restricted cardiac pumping function.

Adult↗
PubMed1991

Phosphodiesterase III inhibition or adrenoreceptor stimulation: milrinone as an alternative to dobutamine in the treatment of severe heart failure.

High levels of endogenous plasma catecholamines in patients with severe congestive heart failure induce a down-regulation of the myocardial beta-adrenoreceptors and thus cause adrenoreceptor agonists, such as dobutamine, to be less effective in the treatment of these patients. Phosphodiesterase III inhibitors work independent of adrenoreceptor activity and plasma catecholamine levels; thus these agents are likely to be more effective in the treatment of severe heart failure. The present study compares both the initial and late hemodynamic effects of dobutamine and milrinone during sequentially administered 24-hour infusions. Twenty patients with severe heart failure (New York Heart Association class III, n = 4; New York Heart Association class IV, n = 16) were investigated. Dobutamine could be administered at the prescribed maximum dose of 15 micrograms/kg/min for 24 hours in only 15 of 20 patients. In three patients the dose was reduced or dobutamine infusion completely stopped because of a drug-related increase in heart rate greater than 140 beats/min. Another 2 of 20 patients showed no hemodynamic improvement over 3 hours at the maximum dose of 15 micrograms/kg/min. Dobutamine administration was also discontinued in these patients on account of the existing unfavorable hemodynamic condition, and therapy with intravenous milrinone was started. All 20 patients responded to milrinone without side effects, although comparison of the hemodynamic effects during a 24-hour infusion was possible in only 15 patients. The 15 patients studied over both observation periods experienced an increase in heart rate from 88.8 to 105.6 beats/min (+ 1 hour; p less than or equal to 0.001) when receiving dobutamine but had no increase with milrinone. Stroke volume increased during dobutamine infusion from 19.3 to 28.9 ml/m2 (+49.6%) after 1 hour and then fell continuously to 25.2 ml/m2 after 12 hours; during milrinone therapy, stroke volume increased from 18.8 to 31.2 ml/m2 (+66%; p less than or equal to 0.001) and remained at this level until the end of the infusion (30.2 ml/m2). Pulmonary capillary wedge pressure (PCWP) decreased (p less than or equal to 0.001) immediately during milrinone therapy from 26.5 to 16.2 mm Hg after 30 minutes and stabilized at 20.1 mm Hg after 24 hours. During dobutamine infusion PCWP showed a delayed decrease from 27.8 to 19.0 mm Hg after 6 hours and subsequently rose to 22.7 mm Hg after 24 hours.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Cardiopulmonary exercise testing (CPX) and transthoracic bioimpedance measurements: new tools for an "old disease" (congestive heart failure).

The purpose of the study was to examine the cardiovascular and cardiopulmonary exercise capacity in patients with symptomatic congestive heart failure more exactly than with conventional investigations, using the simultaneous non-invasive determination of the gas exchange parameters (ergospirometry, CPX) and of the hemodynamic (transthoracic bioimpedance). The reproducibility of the data were measured with each method with repeated tests under the same conditions in healthy subjects and patients with myocardial failure. Therefore we tested 15 patients with documented congestive heart failure repeatedly on a bicycle (semi-supine, +15 watts/min, symptom-limited). The ergospirometric (VO2, VCO2, RER = VCO2/VO2, max. VO2, VO2AT, VE, RR) and the bioimpedance-parameters (CI, SVI, HR) were measured simultaneously during rest and exercise. According to Wasserman et al. we used the VO2AT and the max. VO2 to assign the patients to the different Weber classes: Weber A: greater than 20 ml/min/kg max. VO2, greater than 14 ml/min/kg VO2AT; Weber B: 16 to 20 ml/min/kg max. VO2, 11 to 14 8 to 11 ml/min/kg VO2AT; Weber D: 6 to 10 ml/min/kg max. ml/min/kg VO2AT; Weber C: 10 to 16 ml/min/kg max. VO2, 8 to 11 ml/min/kg VO2AT; Weber D: 6 to 10 ml/min/kg max. VO2, 4 to 8 ml/min/kg VO2AT: Weber E: less than 6 ml/min/kg max. VO2, less than 4 ml/min/kg VO2AT. The V-slope-method according to Beaver et al. allowed for the determination of the anaerobic threshold in 13/15 patients. 2/15 patients didn't reach the anaerobic threshold. Oscillations of the gas exchange parameters due to Cheyne-Stokes-breathing were found in 9/15 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[The effect of hemodynamic changes in 24-hour milrinone infusion on sympathetic activity and the renin-angiotensin-aldosterone system in patients with severe heart failure].

The hemodynamics of 18 patients (subgroup A) with severe heart failure (baseline Cl less than or equal to 1.55 l.min-1.m-2), including three patients with cardiogenic shock, and another 22 patients (subgroup B) with moderate heart failure (baseline Cl from 1.55 to 2.5 l.min-1.m-2) were investigated during a 24 h milrinone infusion, combined with investigation of the response of the sympathetic tone (plasma catecholamine levels) and the renin-angiotensin-aldosterone system to the hemodynamic improvement in both subgroups. Cl increased (p less than or equal to 0.001) to 162.7% after 5 min and further to 206.4% of baseline after 30 min of milrinone therapy in subgroup A, and in B to 139.3% and further to 146.4% after 15 min. PCWP decreased (p less than or equal to 0.001) to 83.8% and further to 65.5% of baseline after 30 min in subgroup A, and to 58.4% in subgroup B. Heart rate decreased (p less than or equal to 0.05) from 99.4 to 94.7 bpm in A and showed a decreasing tendency in B. MAP rose in A from 75.5 to 79.4 after 1 h and further to 83.3 mm Hg (p less than or equal to 0.01) after 24 h; in subgroup B, MAP did not change. Plasma noradrenaline level decreased (p less than or equal to 0.001) in A from 1419.5 (B: 782.9) to 838.2 (B: 529.6) after 1 h and further to 655.1 (B: 467.9) pg/ml after 24 h. Plasma renin decreased (p less than or equal to 0.01) in A from 1047.6 (B: 460.2) to 597.4 (B: 222.5) and further to 392.6 (B: 191.7) microU/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Hemodynamics with dobutamine and milrinone in patients with severe heart failure in an intra-individual comparison].

Hemodynamics during 24-h dobutamine (dob) and subsequent 24-h milrinone (mil) infusion were studied in 20 patients (pts) with severe heart failure (NYHA III: 4 pts, NYHA IV: 16 pts). Three of 20 patients showed a heart-rate increase to 140 bpm and more during dob; five patients were non-responders to dob. Heart rate rose (p less than or equal to 0.001) during dob from 88.8 to 105.6 bpm (+1 hr) and then decreased to 93.0 bpm after 24 h; stroke volume index increased (p less than or equal to 0.001) from 19.3 to 28.9 ml.m-2 (+49.6%) after 1 h and then decreased to 25.2 ml.m-2 after 12 h as did heart rate. During mil heart rate did not change; stroke volume index increased from 18.8 to 31.2 (+66.0%, p less than or equal to 0.001) after 1 h and showed no development of tolerance during the rest of the infusion period. PCWP decreased (p less than or equal to 0.001) during mil from 26.5 to 16.2 mm Hg after 30 min, tending upward again to 20.1 mm Hg after 24 h; during dob the decrease (p less than or equal to 0.01) of PCWP from 27.8 to 19.0 mm Hg after 6 h was delayed, also tending upward during the rest of the infusion period to 22.7 mm Hg after 24 h. There was no sustained decrease of PVR during dob, but after the start of mil infusion PVR decreased (p less than or equal to 0.001) from 312.7 to 172.1 dynes/s/cm-5 (+15 min), remaining on this level during the rest of mil infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Hemodynamics and differentiated CO transfer following fulminant lung embolism and pulmonary artery embolectomy and following recurrent lung embolism].

Pulmonary embolectomy as an emergent surgical treatment after massive pulmonary embolism often is necessary in cardiogenic shock (CS) and even without previous diagnostic. If complete dissolution of the thromboembolus is possible or spreading of microemboli may occur is unknown. Therefore we studied 21 patients surgically treated by embolectomy, ten of these with consecutive cardiogenic shock (CS) and twelve patients after repetitive microembolism and cava-blocking. Besides lung-functional parameters for special CO-diffusion capacity (DLCO), differentiated in membrane (DM) and vascular (VC) component (Roughton and Forster), we measured mean pulmonary artery pressure (PAP) at rest and at exercise. Patients after repetitive embolism showed considerably more diminution of DLCO (-31%) than those after single massive embolic event (-15%) even concomitant by CS (-10%). Repetitive microembolism lowered VC by 21%. Slight decrease of DM was found after CS. Mean pulmonary artery pressure was elevated at rest (26 mm Hg) and exercise (33 mm Hg) after repetitive microembolism and normal after massive embolism or CS. Pulmonary embolectomy may prevent disturbances of DLCO or PAP even after CS. Damage of vascular integrity (VC) was found after microembolism. Pulmonary embolectomy seems to remove total embolic material and therefore seems to be optimal.

Adult↗
PubMed1989

[Mechanical recanalization of chronic coronary artery occlusion by balloon dilatation. Hemodynamic and ventricular kinetic long-term results].

Abundant collaterals may prevent infarction in a region of myocardium supplied by an acutely occluded coronary artery. However, these patients often present with severe angina on exertion which cannot be sufficiently treated with antianginal drugs but require revascularization. Beginning in 1984, recanalization of chronic coronary artery occlusion using balloon catheters was attempted in 48 patients at Medizinische Klinik III, University of Cologne. Interventional therapy was successful in 29/48 patients (60%). The mean diameter narrowing of residual stenoses was 35%. Invasive follow-up at 3 months was possible in 17 of these 29 patients. Restenosis was noted in 41% and reocclusion was found in 18%. In contrast to angiographic findings, clinical symptoms were clearly improved in the majority of cases (88%). This correlates with increased regional contractility of the myocardial region supplied by the previously occluded artery. Contractility was also improved in patients with significant restenosis. The clinical benefit and the improvement of regional myocardial function indicate that it is justified to attempt balloon recanalization in highly symptomatic patients with short distance coronary occlusions despite the relatively high incidence of restenosis and reocclusion.

Angioplasty, Balloon, Coronary↗