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Intermittent substitutive treatments in severely ill patients with acute renal failure are difficult or not suitable because of technical problems and/or hemodynamic instability. Continuous venovenous hemodiafiltration allows an adequate, slow removal of fluid, electrolytes, and waste products by combining diffusive and convective solute transport. Eight patients with acute renal failure, after cardiovascular surgery and cardiogenic shock, were treated by continuous venovenous hemodiafiltration. An automatic system (Equaline System, Amicon Division, USA) was employed. Venous accesses (femoral or subclavian) were used with double lumen catheters. A polysulfone filter (0.4 m2) was used in the study. Blood flow was 30 ml/min and dialysate flow rate 16.6 ml/min. Sterile pyrogen-free hemofiltration substitution fluid was used as dialysate. Mean duration of treatment was 10.3 +/- 3.2 days. After 72 hours blood urea nitrogen levels dropped from 136 +/- 46.13 to 53.5 +/- 12.3 mg/dl and creatinine levels dropped from 6.9 +/- 1.7 to 2.6 +/- 0.9 mg/dl. A controlled steady-state was then maintained. Mean urea clearance was 21 +/- 5.3 ml/min; mean ultrafiltration rate was 20.3 +/- 4.1 L/day. Continuous venovenous hemodiafiltration, with the Equaline System, is effective for the clearance of waste products and is able to maintain perfect fluid balance in catabolic patients with acute renal failure and multiple organ failure.

It has been demonstrated that high dose (up to 0.84 mg/kg over 10 min) dipyridamole echocardiography stress testing is feasible even in the first few hours after coronary artery bypass graft surgery and can be used to assess the beneficial physiological effects of coronary revascularization as well as graft patency. The aim of this study was to assess the role of dipyridamole echocardiography testing performed shortly after myocardial revascularization in the stratification of prognosis during follow-up. We studied 49 consecutive patients (45 males and 4 females; mean age 56 +/- 8 years) referred to our institute for elective myocardial revascularization. Six patients had single, 14 double, and 29 triple vessel disease. Forty-two left internal mammary artery grafts, 16 sequential venous grafts, and 45 single venous grafts were performed. All patients were submitted to dipyridamole echocardiography testing before (range 1-3 days) and shortly after (range 5-7 days) myocardial revascularization, always with the patients off antianginal medication. An arbitrary wall-motion score grading from 0 to 3 (normal, hypokinesia, akinesia, and dyskinesia) was applied to the seven regions into which the left ventricle was divided. Before surgery 48 patients showed wall-motion abnormalities during the test (47 patients also presented ECG changes). Angina occurred in 48 patients. One patient had ischemic ECG changes and angina. The mean wall-motion score was 3.11 per patient before and 6.5 per patient after the test (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Recently, aprotinin has been demonstrated to be effective in reducing post-operative bleeding after open heart surgery. The aim of this study was to evaluate the effectiveness of high dose aprotinin in patients undergoing redo open heart surgery in whom perioperative bleeding is generally increased. Fifty-eight patients, mean age 55 years, underwent a second open heart surgery for single valve replacement in 37 patients (mitral or aortic), for double valve replacement in 16 patients and for coronary artery by-pass grafting in 4 patients. In 30 of the 58 patients (Group A) aprotinin was infused with the following scheme: 2 million KIU in 30 minutes during induction of anesthesia, 2 million KIU in the priming volume of extracorporeal circulation and 500,000 KIU every hour until the end of the surgical procedure. The remaining 28 patients served as control group (Group B). No adverse reactions to aprotinin were observed. There was no significant difference in cardiopulmonary by-pass time and minimum temperature achieved between the two groups of patients. During the operative day blood loss was significantly lower in group A than in group B (492 +/- 336 ml vs. 628 +/- 273 ml) (p < 0.01). This difference was not significant during the following days. However 3 days after the operation a still significant difference was reported in total blood loss between group A and group B (816 +/- 507 ml vs. 1018 +/- 373 ml) (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The object of this study was to assess the usefulness of the dipyridamole-echocardiography test in the early evaluation of coronary artery bypass grafting, when the use of an exercise stress test is precluded. We studied 39 consecutive patients (37 men and two women, mean age 57.3 years) referred to our institute for elective coronary artery bypass. Five patients had single, 12 patients double, 20 patients triple vessel disease, and two had left main stem disease. Nineteen left internal mammary artery grafts, 20 sequential grafts, and 39 single vein grafts were performed. All the patients were subjected to the test before (time range 1 to 3 days) and after (time range 6 to 10 days) the operation in the absence of therapy. Dipyridamole was administered intravenously 0.56 mg/kg over 4 minutes (low dose); if no effect was apparent, an additional 0.28 mg/kg over 2 minutes (high dose) was given. During the test, blood pressure and a twelve-lead electrocardiogram were monitored. An arbitrary wall motion score was derived by dividing the left ventricle into six regions and grading from 0 to 3-normokinetic, hypokinetic, akinetic, and dyskinetic zones. Preoperatively the test was positive in 38 patients as evidenced by wall motion abnormalities (36 patients had electrocardiographic changes) and in one patient by electrocardiographic changes and chest pain; 22 tests were positive after the low dose and 17 after the high dose. Angina was present in 33 patients. Mean wall motion score was 1.64 per patient in the basal condition and 4.03 per patient after the test (p less than 0.001). After coronary bypass in three patients the test was positive at the same dosage that was used preoperatively, as shown by wall motion abnormalities (in two patients by electrocardiographic changes, as well). Four patients had symptoms. Furthermore, at 6 months' follow-up, a treadmill stress test performed in these three patients was positive for ischemia and angina. The wall motion score was 1.25 per patient in the basal condition and 1.53 per patient after the test (no significant difference). When the preoperative wall motion score obtained after dipyridamole echocardiography was compared with the postoperative score, a statistically significant difference was seen: 4.03 per patient versus 1.53 per patient (p less than 001). In eight patients we observed an improvement of basal myocardial contractility after the operation, which indicates the reversibility of wall motion abnormalities observed before coronary bypass. In conclusion our data show that the dipyridamole-echocardiography test is a suitable method for the early assessment of bypass grafting when other methods, exercise dependent, are not indicated.(ABSTRACT TRUNCATED AT 400 WORDS)

The evaluation of coronary reserve within a few hours of aortocoronary bypass surgery could be of extreme utility for the follow-up or therapeutical management of these patients. In 11 men patients who underwent aortocoronary bypass surgery, a dipyridamole echocardiography stress test was carried out before (1 to 3 days), early after (68 to 130 minutes), and 1 week after surgery. The first and third tests were performed using a standard transthoracic approach, while the second was performed by a transesophageal approach. Dipyridamole was administered intravenously at a dose of 0.56 mg/kg body weight (low dose) and eventually adding 0.28 mg/kg body weight (high dose), always in the absence of antiischemic therapy. An arbitrary wall motion score (0 = eukinesia; 1 = hypokinesia; 2 = akinesia; 3 = dyskinesia) was assigned to the seven different myocardial regions in which the left ventricle was divided in order to have a semiquantitative score. Under basal conditions wall motion score per patient in the three series of tests did not change significantly (1.6, 1.4, and 1.5, respectively), while the mean score during dipyridamole administration showed significant differences (3.6, 1.9, and 1.9, respectively), indicative of the results obtained by surgical repair. The test, positive in all patients before surgery, showed wall motion abnormalities and ischemic ECG changes in two patients immediately after surgery by the transesophageal approach. One patient who had a normal basal contraction pattern and an abnormal response after the test developed in the following days a perioperative myocardial infarction, while a second patient in the follow-up period developed low-level effort angina.(ABSTRACT TRUNCATED AT 250 WORDS)

A case is presented of a chronic extrapleural hematoma of the right lung apex after attempted cannulation of the internal jugular vein. Although the percutaneous cannulation of internal jugular vein enjoys wide popularity, this procedure is not without potential for serious and late complications.