[Improved quality of stored packed red blood cells by mechanical rinsing]. / Verbesserte Qualität gelagerter Erythrozytenkonzentrate durch maschinelle Autotransfusion.

BACKGROUND: The transfusion of packed red blood cells (PRBC) is associated with various side effects, including storage damage to PRBCs. The cells change their structure, releasing potassium as well as lactate. Mechanical rinsing, available in many hospitals, is able to remove toxic substances and possibly minimizes the negative side effects of transfusion. OBJECTIVE: The primary aim of our study was to improve the quality of PRBCs before transfusion. The effects of different washing solutions on PRBC quality were analyzed. MATERIAL AND METHODS: This in vitro study compares 30 mechanically washed PRBCs. They were either processed with standard normal saline 0.9% (n = 15, N group) or a hemofiltration solution containing 4 mmol/l potassium (n = 15, HF group) by a mechanical rinsing device (Xtra, LivaNova, Munich, Germany). A subgroup analysis was performed based on the storage duration of the processed PRBCs (7, 14, 37 days). Samples were taken before washing (EKprä), immediately after washing (EKpost) and 10 h later (EKpost10h), after storage in the "wash medium" at room temperature. Concentrations of ATP (probability of survival in transfused erythrocytes), lactate, citrate and electrolytes (potassium, sodium, chloride, calcium) were tested. RESULTS AND CONCLUSION: Mechanical rinsing improves pretransfusion quality of PRBC. Washing with a hemofiltration solution results in a more physiological electrolyte composition. Even 10 h after mechanical rinsing with a hemofiltration solution, the quality of 37-day-old PRBC is comparable to young PRBC that have been stored for 7 days and have not been washed. Washing stored PRBC increases the ATP content, which subsequently leads to an increased probability of survival of red cells after transfusion.

Joint inversion of satellite-detected tidal and magnetospheric signals constrains electrical conductivity and water content of the upper mantle and transition zone.

We present a new global electrical conductivity model of Earth's mantle. The model was derived by using a novel methodology, which is based on inverting satellite magnetic field measurements from different sources simultaneously. Specifically, we estimated responses of magnetospheric origin and ocean tidal magnetic signals from the most recent Swarm and CHAMP data. The challenging task of properly accounting for the ocean effect in the data was addressed through full three-dimensional solution of Maxwell's equations. We show that simultaneous inversion of magnetospheric and tidal magnetic signals results in a model with much improved resolution. Comparison with laboratory-based conductivity profiles shows that obtained models are compatible with a pyrolytic composition and a water content of 0.01 wt% and 0.1 wt% in the upper mantle and transition zone, respectively.

Aortic arch repair: let it beat!

Objective aortic arch repair (AAR) on the beating heart may reduce cross-clamping times and offer improved postoperative cardiac function.Methods A single-center review of all patients (n = 24) who underwent surgical AAR during biventricular repair between 01/2006 and 01/2008 was done. All patients were operated on under cardiopulmonary bypass (CPB) with antegrade cerebral perfusion (ACP). During AAR, 13 patients (group 1) received cardioplegic arrest, and were compared to 11 patients (group 2) who underwent a beating-heart modification with selective myocardial perfusion. Seventeen patients had additional intracardiac lesions and underwent simultaneous correction during the procedure.Results Durations of CPB, AAR and ACP did not differ statistically between groups. Cardioplegic arrest time was significantly lower in group 1 (34 ± 13 vs. 76 ± 11 min, p = 0.02) and resulted in a subsequent reduction of myocardial ischemic damage as borne out by lower postoperative levels of troponin T and CK-MB (2.5 ± 0.7 vs. 7.1 ± 1.4 ng/mL, p = 0.02; 68.7 ± 11.5 vs. 149.1 ± 27.2 U/l, p = 0.03). We observed an enhanced patient recovery with shorter inotropic and ventilatory support times (p < 0.05).Conclusion Pediatric aortic arch correction on a CPB beating heart with selective myocardial perfusion is technically feasible and safe. The reduction of the myocardial ischemic time is effective and results in less myocardial damage.

Does the additional use of heparin-coated extracorporeal circuits (ECC) optimize the effect of modified ultrafiltration (MUF) in pediatric perfusion?

BACKGROUND: Modified ultrafiltration (MUF) has been shown to exert beneficial effects on the coagulation system and the capillary leak after pediatric cardiac surgery using extracorporeal circulation (ECC). The aim of this study was to investigate whether the additional use of heparin-coated circuits is a useful option for improving biocompatibility. METHODS: We randomized 28 children, using heparin-coated ECC circuits in group A (n = 14) and an uncoated equivalent set in group B (n = 14). After congenital heart surgery, MUF was performed post ECC in a standardized fashion. Blood samples were analyzed preoperatively, 10 min, 30 min, 1 h, and 48 h after ECC by flow cytometric analysis (FACSort) using surface antigens CD62/CD41b (platelets) and CD45/CD14 (monocytes). RESULTS: No significant difference was found with respect to mean age (20.6 months vs. 21.6 months), mean body weight (9.2 kg vs. 8.4 kg), mean ultrafiltration rate (9.1 ml/kg vs. 11.4 ml/kg), chest tube drainage, blood products, ICU stay, and 30-d survival. The percentage of CD62/CD41-positive platelets in group A (vs. B) increased up to 118 % at 60 min vs. 130 % ( P < 0.05) and declined to 98 % at 48 h postop. vs. 99 % (n. s.). The percentage of CD45/CD14-positive monocytes in group A (vs. B) increased up to 158 % at 60 min vs. 155 % (n. s.) and declined to 122 % (A) at 48 h postop. vs. 61 % (B) ( P > 0.05). CONCLUSIONS: Heparin coating of ECC in addition to MUF leads to a lower platelet activation. Monocyte surface markers CD45 and CD14 indicated a marked activation during ECC in both groups but additional heparin coating showed a better postoperative regeneration of monocyte markers in the late course indicating a beneficial additive effect.

Influence of parenteral fat administration on the pulmonary vascular system in man.

In 16 patients with multiple injuries the effect of parenteral administration of a fat emulsion on the pulmonary vascular system has been studied. Using the Hewlett Packard 5600 A Intensive Care System, which allows vital parameters to be sampled at a rate of two values per min, pulmonary artery pressure (PAP) was monitored before, during, and after the administration of Lipofundin S 20% (0.24 g/kg/h). In addition right ventricular stroke work index (RVSWI), alveolar-arterial oxygen difference (A-aDO2) and pulmonary shunt (Qs/Qt) were calculated. The results indicate that there are no changes of the PAP, the RVSWI, and the A-aDO2 during the period of observation.

[Experience of labor and obstetrical analgesia]. / Vécu de l'accouchement et analgésie obstétricale.

A prospective study was undertaken at Strasbourg of the assessment of the patients of the techniques used by the obstetric team and of the general atmosphere in which labour and delivery took place. A questionnair of 115 items was analysed by computer using a Pastis-Pascal programme (see attached). The first results, concerning the analysis of 100 cases and taking into account approximately ten variables, gave the following findings: -the intolerable pain factor is related to the period of dilatation; -the analgesic or amnesic factor in the mother influences the satisfaction she experiences in relation to her child; -demand for epidural anaesthesia appeared the same, whether the woman had been prepared by a psychoprophylactic method or not; -psychoprophylactic preparation would not appear to influence the assessment of pain; -women having an epidural anaesthetic never considered their labour to have been intolerable. Discriminant analysis with study of correlations is not possible at present. Given the number of variables to be considered, the population analysed is inadequate. A multicentre study would improve the performance of this research. Our questionnaire is available to any teams who might wish to use it.