A correct estimation of volume status and so-called dry weight in dialysis patients remains a difficult clinical problem. Clinical status and chest X-ray are not sensitive enough, while invasively measured central venous pressures are not routinely available. Recently, the sonographic determination of the diameter and collapse of the inferior vena cava (IVC) has been proposed as a noninvasive method for estimating intravascular volume. We tried to evaluate the clinical relevance of this method in dialysis patients by comparing it with central venous pressures (CVP) and atrial natriuretic peptide (ANP). To establish a normal range and to control for confounding variables, we examined a large number of healthy controls. Furthermore, the influence of tricuspid insufficiency was examined echocardiographically. Measurements of the IVC diameters were well reproducible, with a coefficient of variation for interobserver error of 2.2%, and a coefficient of variation of 1.4% for intraobserver error. The collapse index was less well reproducible and therefore not used for further analysis. In 86 normal controls (age 18 to 76 years), IVC diameters showed a wide variation, and they were not correlated to age, height, weight, or body surface area. However, there was a significant correlation of IVCex to heart rate (r = 0.63, P < 0.001). Therefore, we calculated percentiles of the heart rate-IVCex relation in normals, and compared the results in patients to these. In 10 overhydrated haemodialysis patients, CVP was closely correlated to IVCex (r = 0.72, P < 0.001), but there was a wide interindividual variation of the slope of this relation. An IVCex above the 95th percentile of normal was a good predictor of an elevated CVP (i.e. > 12 cmH2O). In another 39 stable, chronic haemodialysis patients, there was a significant correlation of the intradialytic decrease of ANP and IVCex (r = 0.69, P < 0.001). However, this correlation existed only in patients without tricuspid insufficiency. In summary, sonography of the inferior vena cava is a valuable tool for estimating dry weight in dialysis patients, provided that some caveats are kept in mind: (i) there is a wide variation of IVC diameters in normals, and single measurements are not helpful in individual patients; (ii) there is a significant, inverse correlation between IVC diameters and heart rate, and the precision of intravascular volume assessment is enhanced by interpreting heart rate corrected diameters; (iii) the presence of tricuspid insufficiency leads to unreliable results, as it influences IVC diameters per se. Intravascular volume changes are reflected by IVC measurements, as shown by the correlation to other indices of intravascular volume, such as CVP and alpha-hANP. IVC sonography is noninvasive and easily available; serial measurements allow an estimation of changes of intravascular volume in patients without cardiac filling impairment. However, unlike with body impedance, interstitial volume is not reflected by IVC diameters.
Background: Prior reports of shoulder arthroplasty performed for dislocation-induced arthropathy have included only patients who had had a prior stabilizing procedure. The purpose of this study was to report the results of shoulder arthroplasty in all patients with a prior anterior shoulder dislocation, including both those previously treated operatively and those previously treated nonoperatively. Methods: Fifty-five shoulders undergoing arthroplasty for arthritis following a prior anterior shoulder dislocation were evaluated. Twenty-seven of the shoulders had undergone a prior anterior stabilization procedure. The measures used to evaluate the shoulders included the Constant score, adjusted Constant score, active mobility, subjective satisfaction, radiographic result, and complications. Results: The shoulders were evaluated at a mean of 45.0 months. The Constant score improved from a mean of 30.8 points preoperatively to a mean of 65.8 points at the time of follow-up. The adjusted Constant score improved from a mean of 38.2% to a mean of 79.8%. Active forward flexion improved from a mean of 82.1° to a mean of 138.9°. Active external rotation improved from a mean of 4.0° to a mean of 38.6°. Fifty patients rated the result as good or excellent. Negative prognosticators included an older age at the time of the initial dislocation and a rotator cuff tear. No significant differences in demographic factors, pre-arthroplasty function, post-arthroplasty function, pre-arthroplasty radiographic findings, post-arthroplasty radiographic findings, complication rate, or reoperation rate were noted between the patients treated with a prior operation for the anterior instability and those treated nonoperatively. Conclusions: This investigation documented the good results obtainable with shoulder arthroplasty for the treatment
In the past, cardiac changes in renal failure have commonly been ascribed to hypertension and poorly specified toxic effects ('uraemic cardiomyopathy'). Our recent experimental and clinical studies suggest (a) that cardiac hypertrophy can be dissociated from hypertension and that blood pressures may have only a permissive role, (b) that experimental uraemia is associated with specific activation of pericytes and intermyocardiocytic fibrosis. Cardiac hypertrophy not correlated with elevated blood pressure, and intermyocardiocytic fibrosis not observed in similarly hypertensive non-uraemic patients, have recently been documented in dialysis patients. The implications of these findings may be (a) electrical instability and predisposition to a sudden cardiac death and (b) diastolic cardiac malfunction with impaired LV filling and predisposition to dialysis hypotension. Some evidence for the latter possibility is provided.
We used Doppler echocardiographic techniques firstly to examine left ventricular (LV) filling patterns in dialysis patients, secondly to analyse whether Doppler echocardiographic left ventricular filling pattern is different in patients with recurrent intradialytic hypotension, and thirdly to study the relation between blood pressure decrease during volume subtraction and left ventricular filling pattern. Indices of left ventricular filling patterns of 47 dialysis patients were consistently different when compared to normotensive healthy controls. To further assess the relation of left ventricular filling pattern to blood pressure stability on dialysis, we first compared 24 patients with stable intradialytic blood pressure (BP) and 23 patients with one or more episodes or intradialytic hypotension per month. Patients with recurrent intradialytic hypotension had lower predialysis blood pressure (MAP 89 +/- 13 vs 96 +/- 14 mmHg), more severe concentric hypertrophy (left ventricular mass/volume ratio 2.7 +/- 1.4 vs 2.0 +/- 0.7), and impaired left ventricular filling (Doppler) as indicated by the ratio of early diastolic vs late (atrial) filling (0.66 +/- 0.2 vs 0.95 +/- 0.22). Subsequently we assessed by Doppler technique the effect of a predetermined rate of volume subtraction (during one dialysis session) in patients with or without recurrent intradialytic hypotension. Diastolic filling indices deteriorated consistently prior to the reduction in blood pressure (early diastolic filling 26.8 +/- 15.2 vs 45.4 +/- 10.9% of diastolic filling). It is suggested that impaired left ventricular filling, presumably reflecting disturbed left ventricular compliance, is common in dialysis patients. Findings by noninvasive Doppler techniques suggest a role of abnormal left ventricular distensibility in recurrent dialysis hypotension.
Shoulder arthroplasty in patients with a fixed anterior shoulder dislocation is fraught with difficulties and complications. Although arthroplasty reliably relieved shoulder pain in this population, limited functional results should be expected.
A bilateral, exercise-mediated renal functional abnormality was first described more than a decade ago. The disturbance is specific for hypertension, is seen in different forms of hypertension, and has been studied most extensively in hypertensives with renovascular disease. The bilateral-abnormal exercise renogram identifies the disturbance. Hypertensives with unilateral renovascular disease were studied in the continuing evaluation of the bilateral function disturbance. We examined 31 hypertensives with documented unilateral renovascular disease, all of whom had renography at rest and during 60 to 80 W ergometric exercise. An additional seven normotensives and 17 essential hypertensives served as controls, and had the same sequence of studies. All patients reported upon continued on to an infusion clearance with 131I-hippurate and 111In-diethylenetriamine pentaacetic acid to determine glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) at rest, and during 25 W ergometric exercise. Eighteen of 31 hypertensives with unilateral renovascular disease were found to have a bilateral-abnormal exercise renogram. Clearance examinations in these identified a prominent reduction of the GFR and a lesser decrease in the ERPF during exercise. Hypertensives with normal exercise renograms did not have the exercise mediated abnormal clearance pattern. Similar results were observed in the control population of essential hypertensives, 65% of whom developed the functional disturbance. The seven normotensives controls did not exhibit the exercise mediated function changes. We conclude that an exercise-mediated bilaterally occurring functional disturbance exists in certain hypertensives, who then have a bilateral-abnormal exercise renogram. Associated with this is a distinctly abnormal clearance during exercise which is characterized by a low filtration fraction.
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