Lack of a Fast-Acting Effect of Erythropoietin on Arterial Blood Pressure and Endothelin Level

Abstract: Recombinant erythropoietin (EPO) has been shown to induce vascular smooth muscle contraction in vitro suggesting a rapid acting pressor effect. In addition its chronic administration has been shown to raise plasma endothelin. This study was designed to explore the presence, if any, of fast-acting effects of EPO on the arterial blood pressure and endothelin level in vivo. Nine stable patients with end-stage renal disease (ESRD) were included in a double-blind, crossover, placebo-controlled study using IV bolus injections of either EPO or saline solution administered to patients while they were comfortably seated in reclining chairs and undisturbed in individual climate-controlled rooms. After a 15-min resting period, the bolus injection was given, and blood pressure (BP) and heart rate were measured and recorded automatically every 5 min for 60 min using an electronic device to avoid operator bias/error. In addition, blood samples were obtained for plasma endothelin determination at time 0 and at 5, 30, and 60 min after injection. Patients were studied approximately 2 h before their regularly scheduled dialysis session. The EPO dosage given (50–60 U/kg) was equal to the maintenance dose, routinely administered during dialysis. No significant change was observed in arterial BP, heart rate, or plasma endothelin concentration relative to the baseline values after either EPO or placebo administration. Thus, the results have excluded a rapid effect on BP, heart rate, and endothelin concentration of EPO at therapeutic doses which, when chronically administered, can clearly raise arterial blood pressure in ESRD patients.     

Osteochondral impaction of the femoral head associated with hip dislocation: CT study in 35 patients

Chondral and osteochondral impactions are insults to articular cartilage and subchondral bone of the femoral head during hip dislocation. To evaluate the frequency and sites of femoral head impaction, we reviewed CT scans of 35 patients with hip dislocation (32 posterior and three anterior). Osteochondral impaction fractures were present in 20 (63%) of the 32 patients with posterior hip dislocation and in all three patients with anterior dislocation. In patients with posterior dislocation, the impaction occurred anteriorly in an arc between the 11-o'clock and 1-o'clock positions in all seven cases (100%) of right-sided dislocation and in eight (61%) of 13 cases of left-sided dislocation. Twelve (60%) of the 20 patients with femoral head impaction fracture underwent surgery; osteochondral impaction was substantiated in all 12. In those with anterior dislocation, osteochondral impaction occurred at the posterolateral aspect of the femoral head in an arc between the 4-o'clock and 5-o'clock positions. A high rate of osteochondral impaction after hip dislocation was detected in this series. Observing the site of femoral head impaction allows determination of the type of original dislocation. Alternatively, when the type of original dislocation is known, the site of femoral head impaction can be predicted.     

Posterior capsular fibrosis in professional baseball pitchers: case series of MR arthrographic findings in six patients with glenohumeral internal rotational deficit

In the high-performance athlete, acquired thickening of the posterior joint capsule is a proposed etiology for glenohumeral internal rotational deficit (GIRD). The purpose of this study was to present our MR arthrographic imaging observations of posterior capsular thickening in professional baseball players who present with reduced throwing velocity related to pain and clinical findings of internal rotational deficit of the glenohumeral joint. Our observations of MR imaging features in patients with clinical and arthroscopic manifestations of GIRD lesions include articular surface partial thickness tears of the supraspinatus and infraspinatus tendons, superoposterior subluxation of the humeral head and SLAP tears of the labrum. Although no empiric standard currently exists for the axial dimension thickness of the shoulder capsule, we have observed a thickened appearance of the posterior band of the inferior glenohumeral ligament in these patients.     

Ewing's sarcoma and pregnancy. A case report and review of the literature

This is the fifth reported case of Ewing's sarcoma in pregnancy. Ewing's sarcoma seems to progress rapidly during pregnancy. Treatment should consist of therapeutic abortion followed by chemotherapy, radiation therapy, and surgery if discovered early in pregnancy. Controversy exists as to the treatment late in pregnancy. Chemotherapy during pregnancy has been suggested, but most authors think all consideration should be given to the fetus. Since maternal prognosis is so poor, the fetus should be taken by cesarean section as soon as pulmonary maturity can be documented by amniocentesis. The mother can then be treated appropriately.