Previous studies have suggested that desmopressin may reduce the bleeding diathesis that often complicates open-heart surgery. To pursue this question further, we performed a double-blind, randomized, placebo-controlled trial to determine whether the previously reported beneficial effect of desmopressin on hemostasis during complex cardiac surgery was applicable to all elective cardiac surgical procedures involving cardiopulmonary bypass. In 150 consecutive patients, most of whom underwent primary coronary-artery bypass grafting, we compared the effects of intravenous desmopressin (0.3 microgram per kilogram of body weight) with those of saline placebo on postoperative blood loss and the need to replace blood products. The median amount of blood lost within the first 24 hours after operation was similar in the desmopressin and placebo groups (865 vs. 738 ml; P = 0.26). The postoperative use of blood replacement products did not differ significantly between the groups (1025 ml [95 percent confidence interval, 300 to 4140 ml] in the desmopressin group and 860 ml [247 to 5346 ml] in the placebo group). Desmopressin is believed to exert its hemostatic effect by releasing von Willebrand factor. The level of ristocetin cofactor, a functional index of the level of von Willebrand factor, was increased approximately twofold from base line in both treatment groups 90 minutes and 24 hours after the administration of medication. Similarly, the levels of von Willebrand factor multimers increased uniformly in both groups. These findings may be consistent with a normal stress response of von Willebrand factor to major surgery and could explain our failure to detect a therapeutic effect of desmopressin. We conclude that the majority of patients who undergo elective cardiac surgery receive no hemostatic benefit from the use of desmopressin.

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Three patients developed severe but self-limited hemolytic anemia within 2 weeks of renal transplantation. All three had received kidneys from cadaver donors who were blood group O. Two of the recipients were blood group B while the third was blood group A. There was no pretransplant preparation of the donors or the recipients. Preoperative crossmatch and antibody screen were negative; however, subsequent to the hemolytic episodes, group-specific blood was incompatible and the patients were transfused with group O crossmatch-compatible blood. Blood bank serological tests showed a positive direct antiglobulin test (DAT), and anti-A and anti-B were eluted from group A and B patients, respectively. There was no evidence of hemolysis despite the positive DAT at 37 days following transplantation in two of the three patients who were maintained on cyclosporine immunosuppression. Retrospective analysis of renal transplant records showed that these "autoantibodies" appeared in three of the four renal transplant recipients who were on an immunosuppressive regimen of cyclosporine , with or without prednisone, but not in the 21 recipients who received radiotherapy to the donor kidney in addition to cyclosporine or azathioprine (p = less than 0.001). The possible pathogenetic mechanism for "autoantibody" formation by donor kidney and the role of immunosuppressive agents are discussed.

Piperacillin as a single agent was compared in a prospective randomized trial with carboxypenicillin-aminoglycoside combinations in empirical therapy of serious bacterial infections. The difference in the clinical response rates with piperacillin (77% of 26 infection episodes) and combination therapy (75% of 24 infection episodes) were not statistically significant. Fewer adverse effects occurred in the piperacillin-treated group (42%) than in the combination-treated group (71%) (P = 0.0399 by Fisher's exact test), although neither nephrotoxicity nor hypokalemia alone was significantly less frequent in patients receiving piperacillin. However, the emergence of resistant organisms during therapy was more frequent among patients receiving piperacillin alone (42% of patients) than among patients receiving combination therapy (17% of patients) (P = 0.0465 by Fisher's exact test). Moreover, emergence of resistance accounted for 5 of 9 patients with treatment failure, superinfection, or both when piperacillin was used as a single agent, compared with 2 of 10 similar patients in the combination group (P = 0.1299 by Fisher's exact test). The use of piperacillin as a single agent in the treatment of serious bacterial infections is not advocated, and the addition of an aminoglycoside to prevent emergence of resistance during empirical therapy of such infections is strongly recommended.

Allogeneic bone marrow transplantation (BMT) is the only curative therapy available for patients with myelodysplastic syndrome (MDS). In an attempt to identify prognostic factors influencing outcome, we collected data retrospectively on 60 consecutive adult patients who had undergone BMT at our center for primary MDS or acute myelogenous leukemia evolving from preexisting primary MDS (sAML). Patients were divided into subgroups according to cytogenetic abnormalities based on a recently described International MDS Workshop categorization system. The 7-year actuarial event-free survival (EFS), relapse rate, and nonrelapse mortality (NRM) for all patients were 29% (95% confidence interval [CI], 16% to 43%), 42% (CI, 24% to 67%), and 50% (CI, 37% to 64%), respectively. The EFS for the good-, intermediate-, and poor-risk cytogenetic subgroups were 51% (CI, 30% to 69%), 40% (CI, 16% to 63%), and 6% (CI, 0% to 24%), respectively (P= .003). The corresponding actuarial relapse rates were 19% (CI, 6% to 49%), 12% (CI, 2% to 61%), and 82% (CI, 48% to 99%), respectively (P = .002) with no difference in NRM between the subgroups. Univariate analysis showed cytogenetic category, French-American-British (FAB) subtype, and graft-versus-host disease (GVHD) prophylaxis used to be predictive of relapse and EFS. In multivariate analysis, only the cytogenetic category was predictive of EFS, with the relative risk of treatment failure for the good-, intermediate-, and poor-risk cytogenetic subgroups being 1.0, 1.5, and 3.5, respectively (P = .004). For adults with primary MDS and sAML, even after BMT, poor-risk cytogenetics are predictive of an unfavorable outcome; novel treatment strategies will be required to improve results with allogeneic BMT in this patient population. © 1998 by The American Society of Hematology.