Preliminary characterization of the procoagulant material in human ascites

Disseminated intravascular coagulation invariably accompanies placement of peritoneovenous (LeVeen) shunts, which suggests that ascitic fluid contains procoagulant material capable of activating blood coagulation. In this study, we identified thrombogenic activity in human ascites and the hemostatic pathway by which it acts. Peritoneal fluid was removed percutaneously from patients with ascites due to various causes. Four fractions were prepared by centrifugation: cells, a low-speed, cell-free fluid, a high-speed supernatant, and the precipitate from the high-speed centrifugation. Cellular fractions from all ascitic fluids shortened a one-stage clotting time of normal pooled plasma by 68% in comparison with saline solution and endotoxin controls. Similarly, the cell-free fluids also shortened the clotting time of normal pooled plasma by 41%. The cellular and cell-free fractions shortened the clotting time of factor VIII-deficient plasma but failed to demonstrate procoagulant activity in factor VII-deficient plasma. These fractions had no effect on platelet aggregation or the platelet release reaction. The high-speed precipitate was dissociated by ethylenediaminetetra-acetate (EDTA) into fluid phase and precipitate, both of which demonstrated procoagulant activity. Furthermore, high-speed precipitate contained protein, phospholipid, and sterol in proportions similar to those of plasma membranes and contained membrane-bound vesicles as identified by means of electron microscopy. This material could be rendered inactive by heating to 100 degrees C for 2 minutes or by incubation with phospholipase C for 15 minutes. Finally, the ability of the high-speed precipitate to shorten the clotting time was prevented by preincubation with a monoclonal antibody, which is known to inhibit the procoagulant activity of human tissue factor. We suggest that several entities contribute to the procoagulant properties of human ascites, with procoagulant material deriving at least in part from peritoneal cells. The sedimentable procoagulant factor appears to be associated with cellular membranes or membrane fragments and is thromboplastin-like in its chemical composition, immunoreactivity, and substrate specificity.     

Efficacy of anti-digoxin antibodies in a premature neonate

Through the case report of severe digitalis intoxication in a premature born after 27 weeks of gestation with a birthweight of 800 g, the authors show that anti-digoxin antibodies constitute a very efficacious therapeutic tool which, up to the present, has not been used in prematures.     

Early childhood teachers' preparation and the quality of program outcomes

The issue of the preparation of effective teachers becomes more critical for teachers of early childhood programs. It has been hypothesized that better program quality depends on better-educated teachers. The purpose of this investigation was to explore the importance of a high level of education for all early childhood education teachers. This issue has intrigued early childhood researchers and has prompted a large amount of research studies over the past decades. In order to assess the status of this line of inquiry and to provide guidance for future research, a critical analysis of 40 studies on the preparation of early childhood education teachers and the quality of their educational programs that were published within a 15-year (1989-2004) period is presented here. The analysis consisted of literal and allegorical critical analysis and interpretative critical analyses, which generated results in three main areas that focused on the professional development of the teachers, including teachers' professional development, the importance of a Bachelor's Degree and educational standards for early childhood education teachers.     

Vein patch versus primary closure for carotid endarterectomy. A randomized prospective study in a selected group of patients

During a 4-year period, 136 patients undergoing 152 carotid endarterectomies consented to be randomized to primary or saphenous vein patch closure of the arteriotomy. At operation, before randomization, careful assessment of arterial dimensions and anatomy was made. Patients who had an internal carotid artery (ICA) diameter less than 5 mm, arteriotomy extending more than 3 cm beyond the origin of the ICA, or tortuous or kinked ICAs were not randomized; they received obligatory vein patch closure (necessary in 20% cases). All patients were followed up every 3 months for 1 year and every 6 months thereafter with duplex scanning, ocular pneumoplethysmography, and neurologic assessment. The incidence of atherosclerotic risk factors was equal in the groups and all except one of the patients were male. Perioperative morbidity was not significantly different among those having primary closure (n = 60), saphenous vein patch closure (n = 62), and obligatory vein patch closure (n = 30). Operative time among patients having primary closure (122 +/- 4 minutes) was significantly less (p less than 0.001) than among those having saphenous vein patch closure (150 +/- 3 minutes). Three perioperative strokes were evenly distributed among the groups (2% for all procedures); no deaths and no acute postoperative occlusions occurred. Recurrent disease occurred in 12.9% of patients having saphenous vein patch closure compared with its occurrence in 1.7% of those having primary closure (p less than 0.05). However, most recurrences were moderate stenoses (25% to 50% diameter reduction), all were smooth-surfaced, and none required a second operation. All except one of the recurrences among those patients with saphenous vein patch closure were in the bulb and the origin of the ICA; two had evidence of regression. This finding suggested that thrombus layering in the dilated part of the saphenous vein patch reconstruction was the cause. This study demonstrates that in men with carotid arteries of predetermined minimal dimensions undergoing carotid endarterectomy routine saphenous vein patch closure does not produce superior results, is associated with a higher incidence of early recurrence, and increases operative time. In selected patients with anatomic risk factors for recurrent disease or acute postoperative occlusion, saphenous vein patch closure is appropriate.     

Visual hallucinations on eye closure associated with atropine toxicity. A neurological analysis and comparison with other visual hallucinations

Visual hallucinations of remarkable intensity began shortly after intravenous atropine and persisted for 11 days. They were present only when the eyes were closed and were associated with heightened dreaming and disturbed sleep. The patient remained lucid and described his experiences to his attendants. Our patient's hallucinations bore some resemblance to hypnagogic hallucinations and this became the basis for the hypothesis that the hallucinations originated in the sleep-dream system of the brain stem. It is speculated that a similar site--a metabolic locus minoris resistentiae may play a part in other types of visual hallucinations and in delirium.     

Physiologically based pharmacokinetic modeling of the pregnant rat: a multiroute exposure model for trichloroethylene and its metabolite, trichloroacetic acid

A physiologically based pharmacokinetic (PB-PK) model was developed to describe trichloroethylene (TCE) kinetics in the pregnant rat exposed to TCE by inhalation, by bolus gavage, or by oral ingestion in drinking water. The kinetics of trichloroacetic acid (TCA), an oxidative metabolite of TCE, were described by a classical one-compartment pharmacokinetic model. Among the required model parameters for TCE, partition coefficients (PCs) and kinetic constants for oxidation were determined by vial equilibration and gas uptake methods, respectively. The fat:blood PC was 33.9; the blood:air PC was 13.2; and the fetal tissue:fetal blood PC was 0.51. TCE was readily metabolized with high substrate affinity. In naive and pregnant female rats the maximum velocities of oxidative metabolism were 10.98 +/- 0.155 and 9.18 +/- 0.078 mg/kg/hr, while the estimated Michaelis constant for the two groups of rats was very low, 0.25 mg/liter. The first-order rate constant for oral absorption of TCE from water was 5.4 +/- 0.42/hr-1 in naive rats. With TCA, the volume of distribution (0.618 liter/kg) and the plasma elimination rate constant (0.045 +/- 0.0024/hour) were estimated both from intravenous dosing studies with TCA and from an inhalation study with TCE. By comparison of the two routes of administration, the stoichiometric yield of TCA from TCE was estimated to be 0.12 in pregnant rats. To develop a data base for testing the fidelity of the PB-PK model, inhalation and bolus gavage exposures were conducted from Day 3 to Day 21 of pregnancy and a drinking water exposure from Day 3 to Day 22 of pregnancy. Inhalation exposures with TCE vapor were 4 hr/day at 618 ppm. The TCE concentration in drinking water was 350 micrograms/ml and the gavaged rats received single daily doses of 2.3 mg TCE/kg. Time varying physiological parameters for compartment volumes and blood flows during pregnancy were obtained from the published literature. Using the kinetic parameters determined by experimentation, TCE concentrations in maternal and fetal blood and TCA concentrations in maternal and fetal plasma were predicted from the PB-PK model by computer simulation and compared favorably with limited data obtained at restricted time points during pregnancy for all three routes of exposure. On the basis of the PB-PK model, fetal exposure to TCE, as area-under-the-curve, ranged from 67 to 76% of maternal exposure. For TCA the fetal exposure was 63 to 64% of the maternal exposure. The fetus is clearly at risk both to parent TCE and its TCA metabolite.(ABSTRACT TRUNCATED AT 400 WORDS)     

Eliminating Intensive Postoperative Care in Same-day Surgery Patients Using Short-acting Anesthetics

Background: A multidisciplinary effort was undertaken to determine whether patients could safely bypass the postanesthesia care unit (PACU) after same-day surgery by moving to an earlier time point evaluation of recovery criteria.

Methods: A prospective, outcomes research study with a baseline month, an intervention month, and a follow-up month was designed. Five surgical centers (three community-based hospitals and two freestanding ambulatory surgical centers) were utilized. Two thousand five hundred eight patients were involved in the baseline period, and 2,354 were involved in the follow-up period. Outcome measures included PACU bypass rates and adverse events. Intervention consisted of a multidisciplinary educational program and routine feedback reports.

Results: The overall PACU bypass rate (58%) was significantly different from baseline (15.9%, P < 0.001), for patients to whom a general anesthetic was administered (0.4-31.8%, P < 0.001), and for those given other anesthetic techniques (monitored anesthesia care, regional or local anesthetics; 29.1-84.2%, P < 0.001). During the follow-up period, the average (SD) recovery duration for patients who bypassed the PACU was significantly shorter compared to that for patients who did not bypass, 84.6 (61.5) versus 175.1 (98.8) min, P < 0.001, with no change in patient outcome. Patients receiving only short-acting anesthetics were 78% more likely (P < 0.002) to bypass the PACU after adjusting for various surgical procedures.