Enhanced fibrinolytic activity during cardiopulmonary bypass in open-heart surgery in man is caused by extrinsic (tissue-type) plasminogen activator

The nature of the enhanced blood fibrinolytic activity which is known to occur during cardiopulmonary bypass is not understood. We show here that the cause is an increase in extrinsic (tissue-type) plasminogen activator. In six patients, the nature of the enhanced blood fibrinolytic activity that evolved during cardiopulmonary bypass was characterized by differential inhibition using the fibrin plate method and was shown to be C1-inactivator-resistant (extrinsic-activator activity). The C1-inactivator-resistant-activator activity was completely quenched by an antibody against extrinsic (tissue-type) plasminogen activator but not by antiurokinase, proving that the activity was due to the presence of extrinsic (tissue-type) plasminogen activator. The concentration of extrinsic (tissue-type) plasminogen activator increased during cardiopulmonary bypass and disappeared rapidly thereafter. Fibrinogen, plasminogen and alpha 2-antiplasmin were not consumed during cardiopulmonary bypass, while no increase or occasionally a moderate one in fibrinogen degradation products occurred. This is in accord with the property of extrinsic (tissue-type) plasminogen activator which activates plasminogen predominantly at sites where fibrin is present and not in the free circulation.     

Predictors of cerebral palsy in very preterm infants: the EPIPAGE prospective population‐based cohort study

Aim The aim of this study was to assess the independent role of cerebral lesions on ultrasound scan, and several other neonatal and obstetric factors, as potential predictors of cerebral palsy (CP) in a large population‐based cohort of very preterm infants. Method As part of EPIPAGE, a population‐based prospective cohort study, perinatal data and outcome at 5 years of age were recorded for 1812 infants born before 33 weeks of gestation in nine regions of France in 1997. Results The study group comprised 942 males (52%) and 870 females with a mean gestational age of 30 weeks (SD 2wks; range 24–32wks) and a mean birthweight of 1367g (SD 393g; range 450–2645g). CP was diagnosed at 5 years of age in 159 infants (prevalence 9%; 95% confidence interval [CI] 7–10%), 97 males and 62 females, with a mean gestational age of 29 weeks (SD 2wks; range 24–32wks) and a mean birthweight of 1305g (SD 386g; range 500–2480g). Among this group, 67% walked without aid, 14% walked with aid, and 19% were unable to walk. Spastic, ataxic, and dyskinetic CP accounted for 89%, 7%, and 4% of cases respectively. The prevalence of CP was 61% among infants with cystic periventricular leukomalacia, 50% in infants with intraparenchymal haemorrhage, 8% in infants with grade I intraventricular haemorrhage, and 4% in infants without a detectable cerebral lesion. After controlling for cerebral lesions and obstetric and neonatal factors, only male sex (odds ratio [OR] 1.52; 95% CI 1.03–2.25) and preterm premature rupture of membranes or preterm labour (OR 1.72; 95% CI 0.95–3.14) were predictors of the development of CP in very preterm infants. Interpretation Cerebral lesions were the most important predictor of CP in very preterm infants. In addition, infant sex and preterm premature rupture of membranes or preterm labour were also independent predictors of CP.     

Utility and Safety of Axillo‐subclavian Venous Imaging with Carbon Dioxide (CO2) Prior to Chronic Lead System Revisions

Background: Prior to attempting placement of one or more electrodes to revise existing rhythm control devices, patency of the central veins should be documented, in view of a high incidence of significant chronic occlusions. Since iodinated contrast venography may be contraindicated in select situations, imaging of the axillo‐subclavian venous system with gaseous carbon dioxide (CO₂) was evaluated prospectively in 23 consecutive individuals who were considered for revision of previously implanted pacemaker or automatic cardioverter defibrillator lead systems. Methods: Approximately 20 mL of CO₂ were manually infused via CO₂ primed injection tubing into a vein at or above the level of the antecubital fossa ipsilateral to the side of prior lead placements. Digital subtraction imaging over the axillo‐subclavian region, lower neck, and mediastinum was performed. Formal interpretation was obtained from one of three interventional radiologists and at least one electrophysiologist. Results: Significant venous occlusions were identified in five (22%) patients. Vascular access utilized for the subsequent 18 revisions performed included the imaged patent ipsilateral vein in 14 patients and the contralateral, right‐sided subclavian venous system in three patients. One patient required epicardial left ventricular lead placement. There were no complications from venography. Conclusions: Axillo‐subclavian venography with gaseous CO₂ in patients undergoing pacemaker or implantable cardioverter defibrillator lead revisions is feasible and safe when use of iodinated dye is contraindicated. This technique should be employed in patients with azotemia, dye contrast allergies, or significant inflammation in the vicinity of the intravenous line insertion. (PACE 2010; 790–794)     

Prospective Randomized Comparison of Biphasic Waveform Tilt Using a Unipolar Defibrillation System

Background: A unipolar defihrillation system using a single right ventricular (RV) electrode and the active shell or container of an implantable cardioverter defibrillator situated in a left infraclavicular pocket has been shown to be as efficient in defibrillation as an epicardial lead system. Additional improvements in this system would have favorable practice implications and could derive from alterations in pulse waveform shape. The specific purpose of this study is to determine whether defibrillation efficacy can be improved further in humans by lowering biphasic waveform tilt. Methods: We prospectively and randomly compared the defibrillation efficacy of a 50% and a 65% tilt asymmetric biphasic waveform using the unipolar defibrillation system in 15 consecutive cardiac arrest survivors prior to implantation of a presently available standard transvenous defibrillation system. The RV defibrillation electrode has a 5-cm coil located on a 10.5 French lead and was used as the anode. The system cathode was the active 108 cm² surface area shell (or “CAN”) of a prototype titanium alloy pulse generator placed in the left infraclavicular pocket. The defibrillation pulse derived from a 120-μF capacitor and was delivered from RV ± CAN, with RV positive with respect to the CAN during the initial portion of the cycle. Defibrillation threshold (DFT) stored energy, delivered energy, leading edge voltage and current, pulse resistance, and pulse width were measured for both tilts examined. Results: The unipolar single lead system, RV ± CAN, using a 65% tilt biphasic pulse resulted in a stored energy DFT of 8.7 ± 5.7 J and a delivered energy DFT of 7.6 ± 5.0 J. In ail 15 patients, stored and delivered energy DFTs were < 20 J. The 50% tilt biphasic pulse resulted in a stored energy DFT of 8.2 ± 5.4 J and a delivered energy DFT of 6.1 ± 4.0 J;P = 0.69 and 0.17, respectively. As with the 65% tilt pulse, all 15 patients had stored and delivered energy DFTs < 20 J. Conclusion: The unipolar single lead transvenous defibrillation system provides defibrillation at energy levels comparable to that reported with epicardial lead systems. This system is not improved by use of a 50% tilt biphasic waveform instead of a standard 65% tilt biphasic pulse. (PACE 1995; 18:1369–1373)     

The relationship between emotional intelligence competencies and preferred conflict‐handling styles

Aims The purpose of this study was to determine if a relationship exists between emotional intelligence (EI) and preferred conflict‐handling styles of registered nurses. Background Conflict cannot be eliminated from the workplace therefore learning appropriate conflict‐handling skills is important. Methods Ninety‐four registered nurses working in three south Mississippi healthcare facilities participated in this quantitative study. Ninety‐two valid sets of data instruments were collected for this study. Results Higher levels of EI positively correlated with collaborating and negatively with accommodating. Conclusions The issue of occupational stress and conflict among nurses is a major concern. It is imperative nurses learn how to effectively handle conflict in the work environment. Developing the competencies of EI and understanding how to effectively handle conflict is necessary for nurses working in a highly stressful occupation. Implications for nursing management Effective leadership management includes conflict management and collaboration. The art of relationship management is necessary when handling other people’s emotions. When conflict is approached with high levels of EI, it creates an opportunity for learning effective interpersonal skills. Understanding how EI levels and conflict skills correlate can be used to improve interpersonal relationships in a healthcare facility.     

Initial Clinical Experience with a Rate Responsive Pacemaker

Prism-CLR is a new single chamber unipolar pace, bipolar or unipolar sense, rate responsive pacemaker that utilizes a closed-loop system based on the analysis of the evoked potential for rate adjustment. It also has an automatic output regulation feature for capture verification and threshold search. Five patients in whom this pacemaker was implanted exhibited an appropriate rate increase with exercise and psychological stress. Automatic output regulation functioned appropriately in three of five patients. Preliminary data suggest that Prism-ClR is an effective pacemaker for patients who may benefit from rate responsive pacing. The automatic output regulation recognition algorithm may need modification in some patients.     

Malignant Sustained Ventricular Tachyarrhythmias in Women:

Implantable Defibrillators in Women. Clinical rhythm, heart disease, ejection fraction, defibrillation threshold, recurrent arrhythmias, and mortality were compared in 268 consecutive recipients (213 men and 55 women) of their first implantable cardioverter defibrillator for life-threatening ventricular tachycardia or fibrillation. Women were younger than men, less likely to have structural heart disease, and more likely to have clinical ventricular fibrillation, a higher ejection fraction, and a lower defibrillation threshold. Complications of defibrillator placement were similar in both sexes. Unadjusted survival tended to be higher in women than in men (97% vs 90%, respectively, at 2 years, P = 0.08), largely due to fewer deaths from noncardiac causes or cardiac causes other than arrhythmia (P = 0.04). Women also tended to be at lower, albeit still substantial, risk for recurrent arrhythmias during follow-up (37% vs 52% in men at 2 years, P = 0.11). After adjustment for baseline differences, overall survival, arrhythmia death-free survival, nouarrhythmia death-free survival, and frequency of recurrent arrhythmias were not found to be gender related. Despite their apparent "lower risk" status on initial presentation, women remained at substantial risk for recurrent arrhythmias. This underscores the need to avoid being unduly biased by the "appearance" of health in managing women with malignant arrhythmias. That survival and other clinical endpoints were all ultimately independent of gender emphasizes the importance of other clinical variables in assessing risk from ventricular tachyarrhythmias.     

Current Controversies in Pregnancy and Epilepsy: A Unique Challenge to Nursing

Approximately 11,550 women with epilepsy give birth annually, yet maternity nurses receive little information on how to care for these patients. Children of epileptic mothers are born with an increased incidence of birth defects, and have a higher perinatal mortality rate. Complications such as bleeding during pregnancy, and interventions such as cesarean births and labor inductions are more common among epileptic women, and seizures tend to increase during pregnancy in more than one-third of epileptic women. Informed nursing care is essential to ensure the best possible outcome of these pregnancies.     

The validity of injecting drug users' self-reports about sexually transmitted diseases: a comparison of survey and serological data

Researchers studying the validity of injecting drug users' self-reports have often reported a high degree of correspondence between self-reports and several types of criterion variables. In this study, injecting drug users' responses to questions about prior infection with four sexually transmitted diseases were compared with serological test data. For three of the four diseases studied, discrepancies between survey and serological results were quite large, especially when respondents said they had no previous history of infection. Limitations of serological testing, the questions asked, respondent knowledge and the more traditional concern with respondent veracity are discussed as possible explanations for the observed differences. Study data suggest that use of drug injectors' self-reports to measure infection with sexually transmitted diseases or to validate other measures is a questionable practice. Problems encountered in interpreting study results provide support for more frequent use of experimental or quasi-experimental designs and of multivariate analytic techniques when conducting research on response validity.