Venous blood

In 20 patients undergoing coronary artery bypass grafting, we studied prospectively systemic blood activation, blood loss, and the need for donor blood when using an extracorporeal circuit equipped at random with one of two different venous reservoirs. In 10 patients we used an open venous reservoir system (ORS) consisting of a hard shell venous reservoir with an integral cardiotomy filter, and in 10 patients we used a closed reservoir system consisting of a collapsible venous reservoir and separate cardiotomy reservoir. Concentrations of complement 3a, elastase, thromboxane B2, and fibrin degradation products showed a biphasic course, especially in ORS patients. During bypass, we observed a first peak of levels of complement 3a, thromboxane B2, fibrin degradation products, and elastase, which was higher in ORS patients than in patients with the closed system, because their blood continuously contacted the foreign materials of the filter and air in the open reservoir, which was avoided in the closed reservoir. Intensive blood-foreign material contact also caused the highest (p < 0.05) hemolysis in ORS patients. The larger amount of hemolytic products in ORS patients theoretically resulted in a temporary decrease in capacity of their Kupffer cells to clear endotoxin released after aortic declamping. This theory might explain the significantly (p < 0.01) higher second peak of activated products after declamping that was observed in ORS patients. Due to increased blood activation, the largest (p < 0.001) amount of shed blood loss, greatest (p < 0.05) need for colloid-crystalloid infusion, and largest (not significant) need for donor blood were found in ORS patients (0.8 +/- 0.4 versus 0.2 +/- 0.2 units of packed cells).(ABSTRACT TRUNCATED AT 250 WORDS)

The concentrations of blood components are influenced by a number of preanalytical factors, the importance of which varies [1]. Therefore it is necessary to standardize the specimen collection, as was done by the Committee on Reference Values of the Scandinavian Society for Clinical Chemistry and Clinical Physiology, which in 1975 published its recommendation on the production of reference values in clinical chemistry [2]. It was the very first recommendation of its kind. Since then, new information has accumulated, and it has become necessary to revise the part concerning the preparation of subjects for blood collection, the collection procedure itself, and the subsequent handling of the specimen. Also, The International Federation of Clinical Chemistry (Expert Panel on Theory of Reference Values) has produced its own recommendation [3]. The recommendation described below replaces pp. 39-44 of the former Scandinavian recommendation [2]. The procedure described below is designed for the collection of specimens for the measurement of the majority of components in blood and specimen collection from the cubital vein is described. It can be easily adapted for the collection of blood from other vessels [4]. Certain laboratory investigations require a special protocol. In that case, the preparation of the subject prior to and during specimen collection as well as the procedure itself should be described in sufficient detail to permit reproduction by adequately trained personnel. In any project designed to produce reference values the same protocol for the preparation of individuals and specimen collection should be used throughout the project. The protocol should be described in detail. Thus, it is not satisfactory to state only that the present recommendation was followed. Each section of the recommendation is followed by a check list for points which should be taken into account.

While arterial oxygen desaturation during apnea is a common occurrence in adults and infants, the factors determining the rate of desaturation are poorly understood. We describe a theoretical model which suggests that arterial desaturation during an apneic episode occurs in two stages. In the initial stage (stage 1) the oxygen store in the lung is depleted, while in the second phase of the desaturation process (stage 2) tissue oxygen needs are met predominantly by depletion of the blood store. Our model predicts that preapneic venous oxygenation (SvO2) will strongly influence the rate of the desaturation in stage 1 but not in stage 2. We therefore examined the effect of changing preapneic SvO2 on the rate of arterial oxygen desaturation (SaO2) during stage 1 and stage 2 apnea in anaesthetised 10-20 day-old lambs. Preapneic arterial oxygen saturation was maintained constant. In agreement with the model&#39;s prediction there were two stages to the desaturation process and during stag...

Human immunodeficiency virus (HIV) DNA polymerase chain reaction (PCR) test using venous blood sample has been used for many years in low resource settings for early infant diagnosis of HIV infection in children less than 18 months. The aim of this study was to evaluate and compare the performance characteristics of Amplicor HIV-1 DNA assay version 1.5 following processing of venous blood and dried blood spot (DBS) samples by Roche manual DNA extraction and automated Roche MagNA Pure LC instrument (MP) for HIV-1 DNA PCR testing in Dar es Salaam, Tanzania, in order to scale up early infant diagnosis of HIV infection in routine practice. Venous blood samples from children under 18 months born to HIV-infected mothers between January and April 2008 were collected. Venous blood was used to prepare cell pellet and DBS samples. DNA extractions by manual procedure and MP were performed each on cell pellet, venous blood and DBS samples and tested by Amplicor HIV-1 DNA assay. Of 325 samples i...

Objective of the study: to investigate the lactic acid value in the blood of women in labor and in the amniotic fluid and possibility of using these indicators to predict dystocia development or progression.

Material and methods. A prospective clinical and laboratory study of 136 women in labor with a single-term full-term pregnancy with cephalic presentation of fetus, without a scar on uterus was performed in the Kharkіv Сity Perinatal Center during 2018–2019. Dystocia was diagnosed in 50 women, of whom 33 gave birth by caesarean section, 17 – naturally. In 86 women dystocia was not detected, 17 of them gave birth by caesarean section for other indications, 69 – in a natural way. In addition to the standard examination, the lactate content in the amniotic fluid and in the venous blood was additionally studied by photometric method using a semi-automatic analyzer. Results are analyzed using descriptive statistics and data comparison with nonparametric methods.

Results. In women with dystocia the lactate value in the amniotic fluid is slightly higher compared to women in labor without dystocia (p >0.05), and in venous blood at the beginning of labor practically does not differ between groups. Upon repeated analysis in the blood, the concentration of lactate increased in both groups (p <0.05) with a more significant increase in women in labor with dystocia, especially in women undergoing a cesarean section.

Conclusions. Lactate value in the amniotic fluid is very variable with a tendency to increase in women with dystocia. The relative increase in lactate value in the venous blood during childbirth is most significant in women with labor by caesarean section with dystocia. A significant increase in the lactate value in the venous blood during childbirth in women with dystocia is a sign of depletion of the contractile function of the uterus and may be an additional argument in favor of cesarean section, the absence of a significant increase indicates the possibility of continued delivery in a natural way.

To estimate the influence of delayed umbilical cord clamping at birth on arterial and venous umbilical cord blood gases, bicarbonate (HCO3-), base excess (BE) and lactate in vigorous newborns. University hospital. Prospective observational. Vaginally delivered term newborns. Umbilical cord arterial and venous blood was sampled repeatedly every 45 seconds (T(0)= time zero; T(45)= 45 seconds, T(90)= 90 seconds) until the cord pulsations spontaneously ceased in 66 vigorous singletons with cephalic vaginal delivery at 36-42 weeks. Longitudinal comparisons were performed with the Wilcoxon signed-ranks matched pairs test. Mixed effect models were used to describe the shape of the regression curves. Longitudinal changes of umbilical cord blood gases and lactate. In arterial cord blood, there were significant decreases of pH (7.24-7.21), HCO3- (18.9-18.1 mmol/l) and BE (-4.85 to -6.14 mmol/l), and significant increases of PaCO(2) (7.64-8.07 kPa), PO(2) (2.30-2.74 kPa) and lactate (5.3-5.9 mmol/l) from T(0) to T(90), with the most pronounced changes at T(0)-T(45). Similar changes occurred in venous blood pH (7.32-7.31), HCO3- (19.54-19.33 mmol/l), BE (-4.93 to -5.19 mmol/l), PaCO(2) (5.69-5.81 kPa) and lactate (5.0-5.3 mmol/l), although the changes were smaller and most pronounced at T(45)-T(90). No significant changes were observed in venous PO(2). Persistent cord pulsations and delayed cord clamping at birth result in significantly different measured values of cord blood acid-base parameters.

Human immunodeficiency virus (HIV) DNA polymerase chain reaction (PCR) test using venous blood sample has been used for many years in low resource settings for early infant diagnosis of HIV infection in children less than 18 months. The aim of this study was to evaluate and compare the performance characteristics of Amplicor HIV-1 DNA assay version 1.5 following processing of venous blood and dried blood spot (DBS) samples by Roche manual DNA extraction and automated Roche MagNA Pure LC instrument (MP) for HIV-1 DNA PCR testing in Dar es Salaam, Tanzania, in order to scale up early infant diagnosis of HIV infection in routine practice. Venous blood samples from children under 18 months born to HIV-infected mothers between January and April 2008 were collected. Venous blood was used to prepare cell pellet and DBS samples. DNA extractions by manual procedure and MP were performed each on cell pellet, venous blood and DBS samples and tested by Amplicor HIV-1 DNA assay. Of 325 samples i...

Human immunodeficiency virus (HIV) DNA polymerase chain reaction (PCR) test using venous blood sample has been used for many years in low resource settings for early infant diagnosis of HIV infection in children less than 18 months. The aim of this study was to evaluate and compare the performance characteristics of Amplicor HIV-1 DNA assay version 1.5 following processing of venous blood and dried blood spot (DBS) samples by Roche manual DNA extraction and automated Roche MagNA Pure LC instrument (MP) for HIV-1 DNA PCR testing in Dar es Salaam, Tanzania, in order to scale up early infant diagnosis of HIV infection in routine practice. Venous blood samples from children under 18 months born to HIV-infected mothers between January and April 2008 were collected. Venous blood was used to prepare cell pellet and DBS samples. DNA extractions by manual procedure and MP were performed each on cell pellet, venous blood and DBS samples and tested by Amplicor HIV-1 DNA assay. Of 325 samples i...