Infant cardiopulmonary bypass: a procoagulant state.

BACKGROUND: Procoagulant activity after cardiopulmonary bypass (CPB) in infants may predispose to thrombotic and bleeding complications. The induction of tissue factor and prothrombinase activity on endothelial cell membranes is a primary step in the activation of the extrinsic clotting cascade. The purpose of this study is to characterize the fibrinolytic and endothelial procoagulant state in infants undergoing congenital cardiac repairs with and without CPB. METHODS: Fourteen infants (aged 1 to 12 weeks) underwent repair of congenital cardiac defects. Two patients had closed procedures (controls) and 12 had open cardiac procedures. Serum samples were taken before and after CPB, 1, 4, and 24 hours after CPB. Tissue plasminogen activator, plasminogen activator inhibitor-1, interleukin-1beta, interleukin-6, plasma tissue factor, and factor V levels were measured. Human umbilical vein endothelial cell cultures were incubated with serum taken from the above time points and assayed for induction of tissue factor and prothrombinase activity. RESULTS: Control patients had no change from preoperative values in any of the parameters examined. In experimental patients, tissue plasminogen activator levels peaked at 1 hour after CPB and then decreased to normal by 24 hours. Plasminogen activator inhibitor-1 levels peaked at 4 hours after CPB and returned to baseline by 24 hours. The plasma of all patients had no intrinsic tissue factor activity. Induction of tissue factor activity on umbilical vein endothelial cells peaked immediately and again at 24 hours, whereas prothrombinase activity peaked early and stayed elevated. Serum factor V levels were significantly reduced after CPB, but returned to near baseline levels by 24 hours. CONCLUSIONS: Cardiopulmonary bypass is associated with derangement of the coagulation and fibrinolytic systems in infants. The serum of these patients promotes the induction of endothelial procoagulant activity, suggesting that there may be a hypercoagulable state in the postbypass period.

The nursing care plan problem.

If nursing care plans are related to positive patient outcomes, why don't nurses write them? The authors conducted a study to investigate the effect of variables such as reinforcement, knowledge, values and incentives, and certain demographic characteristics on the writing of nursing care plans. The findings have some important implications for nursing administrators and nursing educators, and emphasize the need for further study and investigation.

Effect of specific teaching techniques on cognitive learning, transfer of learning, and affective behavior of nurses in an in-service education setting.

To test the effects of different teaching techniques on learning, transfer of learning, and affective behavior of nurses, three hypotheses were developed based on Gagne's Theory of Knowledge Acquisition, Ellis' Theory of Transfer of Learning, and Bloom's Theory of Affective Consequences of Knowledge. The hypotheses tested were that an experimental (E) group will learn, transfer, and demonstrate affective behaviors significantly more than control groups. Subjects were 131 staff nurses. The E group (N=36) was taught by means of filmstrip with discussion (FD). Control groups II, III, and IV (N=33, 31, and 31 subjects, respectively) were taught by means of lecture alone (L), lecture with discussion (LD), and filmstrip alone (F), respectively. The content taught was Engel's Theory of Grief and Mourning Process. Pre- and posttests were done to obtain measures on learning and transfer. Results showed that the E group transferred significantly more than the L group; in general, all groups showed significant increases in learning and transfer; film groups transferred significantly more than the lecture groups; subjects preferred LD and FD significantly more than F or L. Implications were made for education of patients, students, and staff.

Use of fibrin sealant as a hemostatic agent after liver biopsy in swine.

PURPOSE: To determine whether fibrin sealant injected into the tract created by liver biopsy can be used to decrease postprocedural bleeding. An innovative delivery system was used to deploy the fibrin sealant. MATERIALS AND METHODS: Fibrin sealant is a hemostatic agent consisting of a suspension of fibrinogen and thrombin. A delivery system was devised whereby fibrin sealant could be injected into the tract created by liver biopsy. Thirty swine were randomized into three groups: control (n = 10), heparin (n = 10), and warfarin (n = 10). Each swine underwent laparotomy and was randomized to undergo three to five open liver biopsies with either a 14-gauge cutting needle in conjunction with the fibrin sealant device or a standard 14-gauge cutting needle alone. Forty-seven biopsy procedures were performed with the device; 64 biopsy procedures were performed without the device. Immediate blood loss per biopsy (mL) was estimated based on the size of the blood stain on a sponge. Specimens were assessed for sample size. RESULTS: Immediate blood loss with and without the device, respectively, was: control, 0.1 mL, 5.4 mL; heparin, 0 mL, 7 mL; warfarin, 0.1 mL, 9.3 mL. These differences were significant (P < .01) for each group of swine. In 43 of 47 biopsies (91%), the device functioned without difficulty. There was no difference in sample size when the device was used. CONCLUSIONS: The fibrin sealant device is effective in reducing bleeding after open liver biopsy in anticoagulated and nonanticoagulated swine. The promising results suggest that a trial of percutaneous liver biopsy in swine should be considered.