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SUMMARY Background Patients with bone marrow failure secondary to chemotherapy often develop thrombocytopenia and require platelet transfusion. Fibrinogen plays an important role in platelet aggregation and the establishment of the primary haemostatic plug. Objectives To compare the effects of in vivo platelet transfusion on clot firmness in thrombocytopenic patients with in vitro-performed fibrinogen concentrate substitution. Materials and methods Thirty patients with haematological malignancy admitted for platelet transfusion were included. Haemostatic effects from platelet transfusion and ex vivo addition of fibrinogen concentrate at three different doses were evaluated by thromboelastometry, with clot firmness as the primary endpoint ( A30 ExTEM assay). Secondary endpoints were other thromboelastometry parameters, thrombin generation parameters, activated partial thromboplastin time ( APTT), prothrombin time PT, fibrinogen and factor XIII levels and a clinical bleeding score. Results Twenty patients (66%) had clinical bleeding signs by prior to transfusion. Platelets increased from 17 (range, 1-109) to 40 (range 2-139) × 109 L−1 following transfusion, with a median corrected count increment of 16·7 (range, 0·8-43·5). The A30 value increased significantly by platelet transfusion from 35 ± 11 to 47 ± 10 mm, with no changes in thrombin generation. Fibrinogen concentrate dose-dependently increased A 30 (to 43 ± 10, 49 ± 9 and 50 ± 9 mm, respectively) and reduced parameters of thrombin generation at high doses. Platelet transfusion, together with fibrinogen concentrate, further increased clot firmness. APTT and PT were within normal range, whereas fibrinogen levels were slightly elevated. Conclusion Fibrinogen concentrate increased clot firmness to the same degree as platelet transfusion in patients with low platelet count requiring platelet transfusion. [ABSTRACT FROM AUTHOR]

New oral anticoagulants like the direct thrombin inhibitor, dabigatran ( Pradaxa®), and factor Xa-inhibitors, rivaroxaban ( Xarelto®) and apixaban ( Eliquis®) are available for prophylaxis and treatment of thromboembolic disease. They are emerging alternatives to warfarin and provide equal or better clinical outcome together with reduced need for routine monitoring. Methods for measuring drug concentrations are available, although a correlation between plasma drug concentrations and the risk of bleeding has not been firmly established. Standard laboratory measures like prothrombin time and activated partial thromboplastin time are not sensitive enough to detect thrombin or factor Xa inhibition provided by new oral anticoagulants. Thus, these standard tests may only be used as a crude estimation of the actual anticoagulation status. Further challenges regarding patients receiving new oral anticoagulants who presents with major bleeding or need for emergency surgery pose a unique problem. No established agents are clinically available to reverse the anticoagulant effect, although preclinical data report prothrombin complex concentrate as more efficient than fresh frozen plasma or other prohaemostatic agents. This review summaries current knowledge on approved new oral anticoagulants and discusses clinical aspects of monitoring, with particular focus on the management of the bleeding patient. [ABSTRACT FROM AUTHOR]

This study introduces a new laboratory model of whole blood platelet aggregation stimulated by endogenously generated thrombin, and explores this aspect in haemophilia A in which impaired thrombin generation is a major hallmark. The method was established to measure platelet aggregation initiated by tissue factor evaluated by means of impedance aggregometry. Citrated whole blood from healthy volunteers and haemophilia A patients with the addition of inhibitors of the contact pathway and fibrin polymerization was evaluated. In healthy persons, a second wave of platelet aggregation was found to coincide with the thrombin burst and to be abolished by thrombin inhibitors. In this system, platelet aggregation in severe haemophilia A ( n = 10) was found to be significantly decreased as compared with healthy individuals (912 ± 294 vs. 1917 ± 793 AU × min, P = 0.003), most probably due to the weak level of thrombin generation. For the first time, analysis of platelet aggregation as induced by endogenously generated thrombin was demonstrated. The new method makes it possible to explore the influence of the coagulation system on platelet function. In contrast to the general understanding, the data suggest that the impaired thrombin generation in haemophilia may affect platelet activation. Future studies will address whether our results may contribute to understanding differences in bleeding phenotypes and response to haemostatic substitution observed among patients. [ABSTRACT FROM AUTHOR]

Background: Major blood loss requires fluid resuscitation for maintaining hemodynamic stability. Excessive volume infusions predispose to dilutional coagulopathy through loss, consumption and dilution of cells and proteins involved in haemostasis. Further treatment with fibrinogen concentrate and/or recombinant activated factor VII (rFVIIa) may be initiated, although the haemostatic effects in a situation with haemodilution are not fully detailed. The present study evaluates haemostatic effect of fibrinogen and rFVIIa and their combination in an in vitro model of haemodiluted whole blood with two commonly used crystalloids. Methods: Eight healthy, male volunteers were enrolled. Outcome variables were clot initiation, propagation and strength assessed by thrombelastographic parameters: clotting time, clot formation time, maximum velocity, time until maximum velocity, maximum clot firmness evaluated at dilution levels of 0% (control), 10%, 30% and 50% with isotonic saline and Ringer's lactate in a model of tissue factor-activated whole blood. Fibrinogen and rFVIIa were additional final reaction concentrations, reflecting commonly used clinically therapeutic dosages. Results: Dose-dependent coagulopathy developed following haemodilution with isotonic saline and Ringer's lactate, characterised by a prolonged clot initiation, reduced clot propagation and reduced clot strength. Fibrinogen improved clot strength and propagation phase while rFVIIa shortened clot initiation, both with a positive dose dependency. Conclusions: The combination of fibrinogen and rFVIIa displays an additive effect and improves overall in vitro whole blood clot formation in a model of in vitro crystalloid-induced haemodilution. [ABSTRACT FROM AUTHOR]

Hypotensive anaesthesia (HA) and acute normovolaemic haemodilution (ANH) are used separately to decrease per-operative blood loss. Reducing blood viscosity by adding ANH to HA may appear profitable in a situation with lowered perfusion pressure and concern about organ ischemia. The aim of this study was to clarify the influence of HA in combination with ANH using crystalloid or colloid as replacement fluid on renal function. Hypotensive anaesthesia was induced in 11 patients referred to major spine surgery using sevoflurane in combination with fentanyl/remifentanil. Acute normovolaemic haemodilution was carried out by drawing venous blood into standard blood bags and replacing it by isotonic saline 0.9% (Group S) or HES 130/0.4 (Group V). Renal function was evaluated before, during and up to 8 h after hypotension as the glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) by means of 51Cr-EDTA and 125I-Hippuran clearances. Lowering mean arterial blood pressure decreased GFR and ERPF in both groups. During hypotension ERPF was lower in Group S (n = 5) than Group V (n = 6). Renal function was normalized postoperatively. We found a positive but non-significant correlation between the relative GFR change and the duration of hypotension. In conclusion, our study demonstrated that renal function, assessed by GFR and ERPF, is transiently reduced during the combination of hypotensive anaesthesia and acute normovolaemic haemodilution. A colloid-based fluid regime (HES 130/0.4) used for haemodilution may preserve renal function to a greater extent than a crystalloid-based regime (0.9% saline). [ABSTRACT FROM AUTHOR]

Although the term rigidity has been used frequently as a personality dimension, the behavioral or operational meaning of the term has never been too clear. It has been used to describe such varied behavior as that of the feeble minded, the brain damage case, the schizophrenic, the neurotic and the ethnic prejudiced. One approach to the study of rigidity is exemplified by the factor analytic studies which have been primarily concerned with determining whether rigidity is a unitary mental trait. Such studies have generally been based upon motor tasks in which the ease with which a subject could perform a well-practiced task in a new way has been taken as a measure of rigidity. Whether rigidity in this sense is a unitary trait is still controversial. Evidence has been presented for separate factors of perspirations, persistence, and inertia.

There have been many recent experiments, which have studied the relationships between perceptual behaviors and need states. The study, which the author is reporting here, is basically personality-centered. This means that the author has used perceptual behavior as a means of studying personality dynamics. An extensive bibliography dealing with the correlations between needs and values and perceptual recognition thresholds for need-related stimuli has accumulated. A few examples of experiments in this area may be noted. Along with these experiments has come a great deal of controversial discussion concerning the nature of the relationships. Many of the articles in this area have been concerned with the nature of the perceptual process itself. In this paper the author is not concerned with the controversial issues concerning the definition of perception. Regardless of the types of mechanisms and processes, which may be involved, the author believes that the obtained correlations afford an excellent opportunity to study personality dynamics. In this report the author is concerned with the expression of sexual and aggressive needs on a sentence completion test and the auditory recognition of sexual and aggressive.

Recent experiments clearly show that a person's needs may affect his thresholds for perceptual recognition. One effect of this is perceptual sensitization, in which needs lower the thresholds for acceptable stimuli. The other effect is perceptual defense, in which needs raise recognition thresholds. Both types of effects have shown the relation of perceptual defense and sensitization to repressed and non-repressed needs. In accordance with perceptual sensitization the content of a subject's Rorschach responses are concepts related to his needs, and the themes of his Thematic Apperception Test (TAT) stories deals with behavior and actions that are expressive of these needs. Clinicians who use projective tests frequently recognize source of error. They often diagnose repressed needs by using various cues other than the content of interpretations. A subject, who fails, for example, to give any aggressive stories on the TAT or to see any aggressive concepts in the Rorschach, becomes suspect, because previous experience has shown that such interpretations are common.

The article discusses an area of human psychology concerning the effect of verbal awareness of one's behavior upon the behavior itself. Consciousness or awareness is said to be characterized by the secondary process, distinguished by its contact with reality, amenability to logic, more precise discrimination, and less overgeneralization. The primary process which governs unconscious behavior is, on the other hand, inaccessible to logic and prone to overgeneralization. The distinction between aware and unaware processes and behavior have relied primarily upon common sense for their support since techniques have not been readily available for studying behavior without awareness in the laboratory. In a study it was found that the acquired response biases would generalize to an ostensibly quite different task. While recently there has been considerable evidence advanced for learning without awareness, there has been but little indication that this learning can influence behavior outside of the very restricted conditions under which it was acquired.

Recent experiments demonstrating that human Ss can show marked learning in the absence of verbal awareness of the reinforcement offer some interesting avenues of research for the personality psychologist. Not only do these experiments suggest new techniques for the study of unconscious processes, but they also have implications for the role of insight in the control of behavior. Psychoanalysis, as well as most other personality theories makes certain distinctions between conscious and unconscious processes with regard to such functions as generalization, transfer, and modifiability of responses. Another reason for the personality psychologist's interest is the individual differences observed in the facility with which Ss learn without verbal awareness.

A letter to the editor is presented in response to an article on the improvement of colloid-induced coagulopathy following the addition of a fibrinogen concentrate.

Societies change over time. Chattel slavery and foot-binding have been abolished, democracy has become increasingly widespread, gay rights have become established in some countries, and the animal rights movement continues to gain momentum. Do these changes count as moral progress? Is there such a thing? If so, how should we understand it? These questions have been receiving increasing attention from philosophers, psychologists, biologists, and sociologists in recent decades. This survey provides a systematic account of recent developments in the understanding of moral progress. We outline the concept of moral progress and describe the different types of moral progress identified in the literature. We review the normative criteria that have been used in judging whether various developments count as morally progressive or not. We discuss the prospects of moral progress in the face of challenges that claim that moral progress is not psychologically possible for human beings, and we explore the metaethical implications of moral progress., (© 2021 The Authors. Philosophy Compass published by John Wiley & Sons Ltd.)

Background: Tranexamic acid (TXA) reduces blood loss and transfusion requirements during craniosynostosis surgery in small children. Possible interaction from TXA on the inflammatory system is unknown., Objective: To evaluate the effect of TXA on a wide range of inflammatory markers in children receiving TXA in a randomized, blinded, and placebo controlled study design., Methods: Thirty children undergoing craniosynostosis surgery with significant blood loss received TXA (bolus dose of 10 mg kg -1 followed by 8 hours continuous infusion of 3 mg kg -1  h -1 ) or placebo in a randomized, double-blinded study design. Using a new proximity extension assays employing a panel of inflammatory biomarkers samples was used for analysis of blood samples obtained pre-operatively, 4 and 24 hours after operation., Results: Ninety-two inflammatory parameters were measured. TXA did not affect any of the measured parameters as compared with placebo. Among 34 of the 92 pro- and antiinflammatory parameters investigated changes were observed between pre-operative, 4 or 24 hours, respectively, reflecting immune activation during surgical stress., Conclusion: TXA administration in a low-dose regimen including bolus followed by 8 hours infusion during craniosynostosis surgery did not change any of 92 inflammatory markers as compared with placebo., (© 2020 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)

Perivascular axillary block was performed on 80 patients by a catheter technique. All patients had a standard dose of 40 ml mepivacaine 1% with adrenaline. Thirty minutes after the injection, the motor and sensory blockade was determined. Eighty-six per cent of the patients had a distinct motor blockade, whereas the remaining 14% had only a slight motor blockade. The sensory blockade was complete in 63%, whereas 37% had lack of analgesia in one or several cutaneous areas. Lack of analgesia was most often found in the cutaneous area of the axillary, musculocutaneous and radial nerves. The frequency of analgesia in the three areas of innervation was analysed with reference to the influence of the age, height and weight of the patient, and of differences in technique: paraesthesias, position of catheter, and unintended puncture of blood vessels. None of these variables seems to be important for the low frequency of analgesia in the three areas of innervation.