Search

Ventricular suction is a common adverse event in ventricular assist device (VAD) patients and can be due to multiple underlying causes. The aim of this study is to analyze the potential of different therapeutic interventions to mitigate suction events induced by different pathophysiological conditions. To do so, a suction module was embedded in a cardiovascular hybrid (hydraulic-computational) simulator reproducing the entire cardiovascular system. An HVAD system (Medtronic) was connected between a compliant ventricular apex and a simulated aorta. Starting from a patient profile with severe dilated cardiomyopathy, four different pathophysiological conditions leading to suction were simulated: hypovolemia (blood volume: -900 ml), right ventricular failure (contractility -70%), hypotension (systemic vascular resistance: 8.3 Wood Units), and tachycardia (heart rate:185 bpm). Different therapeutic interventions such as volume infusion, ventricular contractility increase, vasoconstriction, heart rate increase, and pump speed reduction were simulated. Their effects were compared in terms of general hemodynamics and suction mitigation. Each intervention elicited a different effect on the hemodynamics for every pathophysiological condition. Pump speed reduction mitigated suction but did not ameliorate the hemodynamics. Administering volume and inducing a systemic vasoconstriction were the most efficient interventions in both improving the hemodynamics and mitigating suction. When simulating volume infusion, the cardiac powers increased, respectively, by 38%, 25%, 42%, and 43% in the case of hypovolemia, right ventricular failure, hypotension, and tachycardia. Finally, a management algorithm is proposed to identify a therapeutic intervention suited for the underlying physiologic condition causing suction.

The amount of blood loss determined in orthognathic surgery differs greatly among studies. This can be attributed to the inhomogeneity in study cohorts analysed, but may also be a result of the varying methodologies used for blood loss determination. However, this has yet to be explored. Thus, the aim of this study was to investigate the extent to which the formula and time point used to measure blood loss affect the blood loss volume, determined in a homogeneous cohort undergoing bimaxillary surgery. Blood loss was calculated at 24 and 48 hours postoperatively using the haemoglobin balance method and the formula of Hurle et al. The estimated total blood volume was established based on the formulae of Nadler et al. and Choi et al. Differences in blood loss volume with respect to time point and formula were analysed and compared. Fifty-four patients were included in the final analysis. Statistically significant differences in blood loss were observed: a significant increase in the blood loss volume from 24 hours to 48 hours postoperatively was detected. When comparing the formulae used, blood loss differed significantly at 24 hours after surgery; however no such difference resulted at 48 hours postoperatively. These findings imply that the time point of measuring blood loss is highly relevant, whereas the formulae applied seem to have less of an impact on the blood loss volumes calculated.

Acute normovolemic hemodilution (ANH) is associated with low oxygen carrying capacity of blood and purposed to cause renal injury in perioperative setting. It is best accomplished in a perioperative setting by a colloid such as hydroxyl ethyl starch (HES) due its capacity to fill the vascular compartment and maintain colloidal pressure. However, alterations of intra renal microvascular perfusion, flow and its effects on renal function and damage during ANH has not been sufficiently clarified. Based on the extensive use of HES in the perioperative setting we tested the hypothesis that the use of HES during ANH is able to perfuse the kidney microcirculation adequately without causing renal dysfunction and injury in pigs. Hemodilution (n = 8) was performed by stepwise replacing blood with HES to hematocrit (Hct) levels of 20% (T1), 15% (T2), and 10% (T3). Seven control animals were investigated. Systemic and renal hemodynamics were monitored. Renal microcirculatory perfusion was visualized and quantified using contrast-enhanced ultrasound (CEUS) and laser speckle imaging (LSI). In addition, sublingual microcirculation was measured by handheld vital microscopy (HVM). Intrarenal mean transit time of ultrasound contrast agent (IRMTT-CEUS) was reduced in the renal cortex at Hct 10% in comparison to control at T3 (1.4 ± 0.6 vs. 2.2 ± 0.7 seconds, respectively, P

IntroductionIn patients with mitral annular disjunction (MAD), it can be difficult to assess the severity of mitral regurgitation (MR), as they present with a prolapsing volume (i.e. volume resulting from mitral valve prolapse, blood volume shift) rather than a regurgitant jet. The influence of the mitral prolapsing volume (MPV) on cardiac dimensions is unknown. We hypothesised that the severity of MR is underestimated in these patients. Our aim was to measure MPV and to investigate its influence on cardiac dimensions in patients with MAD.MethodsWe retrospectively included 131 consecutive patients with MAD from our institution’s echocardiographic database. Transthoracic echocardiography was used to assess MPV. Additionally, we established a control group of 617 consecutive patients with degenerative mitral valve disease and performed propensity score matching.ResultsMedian MPV in the MAD group was 12 ml. MPV was an independent predictor for left ventricular end-diastolic (LVEDD) and end-systolic diameter (LVESD) and left atrial volume (allp 15 ml), LVEDD (56 ± 6 mm vs 51 ± 6 mm,p p p = 0.04] were significantly increased compared to matched patients with degenerative mitral valve disease and similarly assessed severity of MR.ConclusionDue to a volume shift based on the MPV rather than an actual regurgitant jet, MR severity cannot be assessed adequately in MAD patients. Increased MPV induces ventricular and atrial enlargement. These findings warrant future studies to focus on MPV as an additional parameter for assessment of the severity of MR in MAD patients.

BACKGROUND: Circulating tumour cells (CTCs) can be used to monitor cancer longitudinally, but their use in non-small cell lung cancer (NSCLC) is limited due to low numbers in the peripheral blood. Through diagnostic leukapheresis (DLA) CTCs can be obtained from larger blood volumes.METHODS: Patients with all stages of NSCLC were selected. One total body blood volume was screened by DLA before and after treatment. Peripheral blood was drawn pre- and post DLA for CTC enumeration by CellSearch. CTCs were detected in the DLA product (volume equalling 2 × 108 leucocytes) and after leucocyte depletion (RosetteSep, 9 mL DLA product). Single-cell, whole-genome sequencing was performed on isolated CTCs.RESULTS: Fifty-six patients were included. Before treatment, CTCs were more often detected in DLA (32/55, 58%) than in the peripheral blood (pre-DLA: 18/55, 33%; post DLA: 13/55, 23%, both at p CONCLUSIONS: DLA detected nine times more CTCs than in the peripheral blood. The sustained presence of CTCs in DLA after treatment was associated with therapy failure and shortened PFS.TRIAL REGISTRATION: The study was approved by the Medical Ethical Committee (NL55754.042.15) and was registered in the Dutch trial register (NL5423).

Of all physiological systems, the cardiovascular system takes on the most profound adaptation in pregnancy to support fetal growth and development. The adaptations that arise are systemic and involve structural and functional changes that can be observed at the cerebral, central, peripheral, and microvascular beds. This includes, although is not limited to increased heart rate, stroke volume and cardiac output with negligible change to blood pressure, reductions in vascular resistance and cerebral blood flow velocity, systemic artery enlargement, enhanced endothelial function. All of this takes place to accommodate blood volume expansion and ensure adequate fetal and maternal oxygen delivery. In some instances, the demand placed on the vasculature can manifest as cardiovascular maladaptation and thus, cardiovascular complications can arise. Exercise is recommended in pregnancy because of its powerful ability to reduce the incidence and severity of cardiovascular complications in pregnancy. However, the mechanism by which it acts is poorly understood. The first aim of this review is to describe the systemic adaptations that take place in pregnancy. Secondly, this review aims to describe the influence of exercise on these systemic adaptations. It is anticipated that this review can comprehensively capture the extent of knowledge in this area while identifying areas that warrant further investigation.

The aim of this systematic review was to summarize the evidence on the acute and long-term effects of exercise training on PV, in both trained and untrained individuals and to examine associations between changes in %PVV and change in physical/physiological performance. Despite the status of participants and the exercise duration or intensity, all the acute studies reported a significant decrease of PV (effect size: 0.85

Blood loss (BL) during posterior spinal fusion for adolescent idiopathic scoliosis (AIS) may be estimated using a variety of unproven techniques. Patient care and research on BL are likely impacted by a lack of standardization. A novel FDA-approved blood volume (BV) analysis system (BVA-100 Blood Volume Analyzer) allows rapid processing with > 97% accuracy. The purpose of this study was to investigate common methods for BL estimation. BV assessment was performed with the BVA-100. After obtaining a baseline sample of 5 mL of blood, 1 mL of I-131-labeled albumin was injected intravenously over 1 min. Five milliliter blood samples were then collected at 12, 18, 24, 30, and 36 min post-injection. Intravenous fluid was minimized to maintain euvolemia. Salvaged blood was not administered during surgery. BL was estimated using several common techniques and compared to the BV measurements provided by the BVA-100 (BVABL). Thirty AIS patients were prospectively enrolled with major curves of 54° and underwent fusions of 10 levels. BL based on the BVA-100 (BVABL) was 519.2 [IQR 322.9, 886.2] mL. Previously published formulas all failed to approximate BVABL. Multiplying the cell saver volume return by 3 (CS3) approximates BVABL well with a Spearman correlation coefficient and ICC of 0.80 and 0.72, respectively. An extrapolated cell salvage-based estimator also showed high intraclass correlation coefficient (ICC) and Spearman coefficients with less bias than CS3. Published formulaic approaches do not approximate true blood loss. Multiplying the cell saver volume by 3 or using the cell salvage-based estimator had the highest correlation coefficient and ICC. Prospective cohort Level 2.

To investigate the impact of intraoperative blood transfusion on outcomes in patients who had major thoracic and lumber posterior spine instrumentation surgery. Retrospective study included patients who underwent major spine surgery between 2013 and 2017. Patients’ demographics, surgical charts, anesthesia charts, discharge charts and follow-up outpatient charts were reviewed. Data collection included: age, gender, BMI, Charlson Co-morbidity Index (CCI) scores, American Society of Anesthesiologists (ASA) scores, amount of estimated blood loss [% estimated blood volume (%EBV)], amount of blood transfused during surgery and post-surgery before discharge, number of fusion levels, pre- and postoperative hemoglobin (Hb) levels, and length of hospital stay. Also collected in-hospital postoperative complications (cardiovascular, pulmonary, infections and deaths). Patients’ postoperative intubation status data documented. Reviewed follow-up charts to document any complications. Sample size = 289; No transfusion = 92; transfusion = 197. Transfused patients were significantly older, p

We investigated the efficiency of mitoxantrone (MIT) and high-dose cytarabine (Ara-C) chemotherapy followed by G-CSF and G-CSF/GM-CSF treatments for the mobilization of peripheral blood stem cells (PBSCs) in patients with leukemia and lymphoma. MIT was intravenously injected at 10 mg/(m2·d) for 2 to 3 days, followed by Ara-C injected intravenously at 2 g/m2 every 12 hours for 1 to 2 days. When white blood cell count recovered from the lowest value, 5 to 7.5 μg/ (kg·d) G-CSF was administered in 23 patients for 5 to 7 successive days. Another 27 patients received 3-5 μg/ (kg·d) G-CSF and 3-5μg/ (kg·d) GM-CSF. Autologous peripheral blood mononuclear cells were collected. Levels of CFU-GM and CD34+ cells were determined after unfreezing. The CD34+ cells and CFU-GM yields of 27 patients in G-CSF plus GM-CSF combination group [(8.79±3.11)×106/kg, (3.52±1.34)×105/kg, respectively] were significantly higher than those of patients receiving G-CSF alone (n=23) [(6.14±2.06)×106/kg, (2.03±1.06)×105/kg, respectively (P < 0.05)]. No obvious changes of T lymphocyte subsets in patients were observed when using G-CSF/GM-CSF, but levels of CD34+ cells increased gradually (P>0.05). The end-point separation blood volume was all above trebling TBV. No severe complications were observed during the mobilization and collection. Autologous PBSCT obtained quick hematopoietic reconstitution. In conclusion, MA chemotherapy combined with G-CSF alone and G-CSF/GM-CSF can safely and effectively mobilize autologous PBSCs, while G-CSF plus GM-CSF is superior to G-CSF alone. Large volume leukapheresis is an important method to enhance the production rate of stem cells and decrease harvesting time.

Sublingual nitroglycerin (SL NTG) is useful for treating acute decompensated heart failure, possibly by increasing splanchnic capacitance and reducing left ventricular (LV) preload. We evaluated a radionuclide method to study these effects, initially in subjects without heart failure.Red blood cells were labelled by an in vitro method. Abdominal and chest images were obtained at rest, showing relative regional blood volumes. The abdomen was then re-imaged during progressive escalation of intrathoracic pressure using continuous positive airway pressure to assess baseline splanchnic capacitance (pressure-volume relationship, PVR) and compliance (slope of PVR). The procedure was repeated after 0.6 mg SL NTG, followed by chest images. Relative splanchnic blood volume increased at rest after SL NTG (P.002), signifying an increase in splanchnic capacitance. The slope of the splanchnic PVR decreased in proportion to the baseline PVR (P = .0014), signifying increased compliance. The relative pulmonary blood volume decreased in proportion to the increase in splanchnic blood volume (P = .01).A semi-quantitative radionuclide method demonstrated the effect of SL NTG for increasing splanchnic capacitance and compliance, with a proportional decrease in pulmonary blood volume. These data may be applied to quantitatively evaluate the importance of splanchnic vasodilation as a mechanism of LV preload reduction in the treatment of heart failure.NCT02425566.

BACKGROUND Bioelectrical impedance analysis (BIA) devices have been advocated to guide volume management in hemodialysis (HD) patients. We hypothesized that understanding the dynamics of fluid shifts in different body segments may provide additional insight on preventive measures to reduce the risk of intradialytic hypotension. METHODS A prospective observational study was conducted among 42 HD patients at risk of hypotension who were admitted as emergencies inpatient. RESULTS A total of 191 BIA measurements were made during the 42 HD sessions, and hypotension occurred during 52 measurements (27%). The extracellular water (ECW) to intracellular water ratio (EIR) was measured in different body segments and declined significantly only in the non-access arm with increasing HD session duration (β = -0.04; 95% confidence interval (CI): -0.05 to -0.03, p

Aim Peri-/intaventricular hemorrhage (P/IVH) is a common condition in preterm neonates and is responsible for substantial adverse neurological outcome especially in extremely low birth weight infants. As hematocrit after birth is a surrogate marker for blood volume, this study aimed to evaluate the effect of initial hematocrit values after birth on P/IVH development in extreme low birth weight (ELBW) neonates. Patients and methods A prospective cohort analysis of 92 eligible ELBW neonates was performed. The relationship between initial hematocrit values in ELBW neonates after birth and subsequent development of P/IVH was examined. Results Twenty-nine of 92 infants developed P/IVH. There were significant differences in initial Hct and maximum carbon dioxide (max PCO2) in the first 3 days levels in the P/IVH group compared with no P/IVH group. Initial Hct level at birth in the P/IVH group were significantly lower than the no P/IVH group while max PCO2 in the first 3 days were found to be significantly high in the P/IVH group. There were no significant differences in other baseline demographic, perinatal, and neonatal characteristics while in univariate analysis, higher gestational age and initial Hct were associated with decreased likelihood of P/IVH. In multiple regression analysis after adjustment, only initial Hct remained significantly associated with P/IVH. There was no difference between the population by subgroups of IVH (IVH I-II and IVH III-IV) according to hematocrit and the severity of IVH. Conclusion Higher initial Hct at birth is associated with decreased P/IVH in ELBW infants. We hypothesized the argument that ELBW infants who have lower initial Hct at birth have less suboptimal volume status that predisposing lower cerebral blood flow and the resultant decrease in cerebral blood flow precede the development of P/IVH.

Hematocrit (Hct) values after the initiation of cardiopulmonary bypass (CPB) must be maintained appropriately to avoid perioperative complications. Therefore, an accurate prediction is required. However, the standard prediction equation often results in actual values that are lower than the predicted values. This study aimed to clarify the limits of agreement (LOA) and bias of the prediction equations and investigate better the prediction equations. A retrospective study was performed on adult patients between April 2015 and December 2020. Study 1 included 158 patients, and Study 2 included 55 patients. The primary outcomes were the LOA and bias between the predicted and measured Hct values after the initiation of CPB, and two studies were conducted. In Study 1, total blood volume (TBV) was estimated, and the new blood volume index (BVI) was calculated. BVI was also evaluated for the overall value and gender differences. Therefore, the patient's background was compared by gender differences. In, Study 2 the conventional predicted equation (Eq. 1), the predicted equation using the new BVI (Eq. 2), and the predicted equation using the new BVI including physiological factors in the TBV equation (Eq. 3) were compared. In Study 1, BVI was 53 (44-67) mL/kg. In Study 2, bias ± LOA was - 2.5 ± 6.8% for Eq. 1, 0.1 ± 6.6% for Eq. 2, and 0.4 ± 6.2% for Eq. 3. The new equation is expected to predict the Hct value after the initiation of CPB with better LOA and bias than the conventional equation.

The work deals with the current state of the problem of creation and clinical use of blood substitutes with gas transport function. Blood shortage is an important healthcare problem globally anticipated to become more problematic as people live longer and donor numbers reduces. So, there is a need for an alternative red cell product. The technological directions for the development of blood substitutes with gas transport function are described. The analysis of conducted researches of blood substitutes on the basis of modified hemoglobin, perfluorocarbons, as well as the use of molecular, cellular and nanotechnologies was carried out. The term “blood substitute” does not accurately describe the current candidate products because they typically have only two limited functions: carrying and delivering oxygen and augmenting blood volume. Although no single product can yet imitate all the properties of the blood, substantial progress has been made, especially in the development of hemoglobin based oxygen carriers. The perfluorocarbons are synthetic cyclic or linear hydrocarbons occasionally containing oxygen or nitrogen atoms, and the hydrogen atoms are replaced by fluorine atoms in them. They easily solubilize and release gases without interacting with them. The quantity of gas dissolved is linearly related to its partial pressure. The article presents the results of experimental study and clinical use (1984–2010) of perftorane in acute hemorrhage and hemorrhagic shock, traumatic brain injury, postresuscitation disease, acute myocardial infarction, septic shock, acute poisoning, fat embolism, as a component of cardioplegia under cardiosurgical interventions, vascular surgery and transplantology. Potential advantages of the use of blood substitutes with gas transport function as compared to allogeneic blood are demonstrated. The current state of the problem of creating and studying blood substitutes with gas transport function allows us to conclude that at present this group of drugs remains a potential that has not yet been realized, since they are not literally blood substitutes. Existing single drugs with gas transport function that have been used clinically cannot completely replace the blood function and do not allow to stop using donor red blood cells, but they allow you to gain precious time, making a decisive contribution to saving patients in critical conditions and to encourage further development of more modern blood substitutes. We are deeply convinced that these blood substitutes, which model the most important oxygen transfer function of the blood, will take a worthy place in the future among various methods that is an alternative to the use of donor blood.

The utility of tranexamic acid (TXA) in patients with Marfan syndrome (MFS) is uncertain given associated aberrations within the vasculature and clotting cascade. Therefore, this study aimed to assess the association of TXA use with intraoperative blood loss and allogeneic blood transfusions in patients with MFS who underwent spinal arthrodesis. We queried our institutional database for MFS patients who underwent spinal arthrodesis for scoliosis between 2000 and 2020 by one surgeon. We excluded procedures spanning

Background Currently, the accepted effective method for assessing blood volume status, such as measuring central venous pressure (CVP) and mean pulmonary artery pressure (mPAP), is invasive. The purpose of this study was to explore the feasibility and validity of the ratio of the femoral vein diameter (FVD) to the femoral artery diameter (FAD) for predicting CVP and mPAP and to calculate the cut-off value for the FVD/FAD ratio to help judge a patient’s fluid volume status. Methods In this study, 130 patients were divided into two groups: in group A, the FVD, FAD, and CVP were measured, and in group B, the FVD, FAD, and mPAP were measured. We measured the FVD and FAD by ultrasound. We monitored CVP by a central venous catheter and mPAP by a Swan-Ganz floating catheter. Pearson correlation coefficients were calculated. The best cut-off value for the FVD/FAD ratio for predicting CVP and mPAP was obtained according to the receiver operating characteristic (ROC) curve. Results The FVD/FAD ratio was strongly correlated with CVP (R = 0.87, P P 2O, and an FVD/FAD ratio ≤ 1.467 had the best test characteristics to predict a CVP ≤ 10 cmH2O. An FVD/FAD ratio ≥ 2.03 had the best test characteristics to predict an mPAP ≥ 25 mmHg. According to the simple linear regression curve of the FVD/FAD ratio and CVP, when the predicted CVP ≤ 5 cmH2O, the FVD/FAD ratio was ≤ 0.854. Conclusion In this study, the measurement of the FVD/FAD ratio obtained via ultrasound was strongly correlated with CVP and mPAP, providing a non-invasive method for quickly and reliably assessing blood volume status and providing good clinical support.

International audience; It is important to develop a better understanding of placental insufficiency given its role in common maternofetal complications such as preeclampsia and fetal growth restriction. Functional magnetic resonance imaging offers unprecedented techniques for exploring the placenta under both normal and pathological physiological conditions. Dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) is an established and very robust method to investigate the microcirculatory parameters of an organ and more specifically its perfusion. It is currently a gold standard in the physiological and circulatory evaluation of an organ. Its application to the human placenta could enable to access many microcirculatory parameters relevant to the placental function such as organ blood flow, fractional blood volume, and permeability surface area, by the acquisition of serial images, before, during, and after administration of an intravenous contrast agent. Widely used in animal models with gadolinium-based contrast agents, its application to the human placenta could be possible if the safety of contrast agents in pregnancy is established or they are confirmed to not cross the placenta.

Objective\ud To estimate iron losses and disease severity following 19th century bloodletting in patients with pneumonia.\ud \ud Study design and setting\ud Benefits of bloodletting in pneumonia patients were contested during the 19th century. Although large blood volumes during infection were removed there was no systematic data collection assessing efficacy and knowledge of iron composition of blood was rudimentary. This observational analysis of historical data quantifies iron losses in pneumonia cases in relation to disease severity.\ud \ud Results\ud Based on one detailed case series average blood volume removed for survivors was 830 ml (range 114 - 2272 ml), and mean recovery times were shorter in patients bled within 2 days of illness (p2 days of illness (p=0.012). Across several European hospitals average case fatality in pneumonia patients receiving phlebotomy was higher than in those treated without phlebotomy (19.9% vs 12.8%, OR 1.55, 95% CI 1.38-1.74, P

Purpose Sympathetic activation results in a functional distribution of venous blood from the unstressed reservoir to the hemodynamically active stressed compartment. Such redistribution has been hypothesized to contribute importantly to the elevated filling pressures observed in decompensated heart failure and cardiogenic shock (CS). We recently reported a novel computational method to estimate SBV by fitting measured hemodynamic data from patients to outputs from a cardiovascular model. We hypothesized that estimated stressed blood volume (eSBV) may correlate with severity and clinical outcomes in cardiogenic shock. Methods Hemodynamic parameters including eSBV were compared among a subset of patients from the Cardiogenic Shock Working Group (CSWG) registry who had a complete set of hemodynamic data. eSBV was compared across shock etiologies (AMI vs HF-CS), SCAI stage, and between survivors and non-survivors. Results Among 528 CSWG registry patients analyzed, 25.4% had AMI-CS and 61.9% had HF-CS. Mean eSBV was 2423 ± 531 mL/70 kg (normal value ∼1500 mL) and was similar between the AMI-CS and HF-CS subgroups (2421 ± 478 vs 2342 ± 599 mL/70kg, p=0.90). eSBV increased with increasing SCAI stage (B, 2029 ± 540; C, 2305 ± 505; D, 2496 ± 507; E, 2707 ± 420 mL/70 kg, p Conclusion eSBV is a novel integrated index of congestion which correlates with shock severity. eSBV was higher in patients with HF-CS who died while no difference was observed in AMI-CS, suggesting that congestion may play a more significant role in the deterioration of patients with HF-CS.

BACKGROUND: Aerobatic pilots must withstand high and sudden acceleration forces (Gz) up to 10 Gz. The physiological consequences of such a succession of high and abrupt positive and negative Gz on the human body over time remain mostly unknown. This case report emphasizes changes in physiological factors such as cerebral oxygenation and heart rate dynamics collected in real aerobatic flights.CASE REPORT: A 37-yr-old man, experienced in aerobatic flying, voluntarily took part in this study. During two flight runs (15-20 min), the pilot performed aerobatic maneuvers with multiple high (10 Gz) positive and negative accelerations. During the flights he wore a Polar heart rate sensor while cerebral oxygenation was measured continuously over his prefrontal cortex via near-infrared spectroscopy (NIRS). NIRS allows for measurement of the relative concentration changes of oxygenated hemoglobin (O2Hb) and deoxygenated hemoglobin (HHb), making it possible to determine cerebral oxygenation and hemodynamic status.DISCUSSION: The continuous in-flight monitoring of O2Hb and HHb revealed the large effects of successive positive and negative Gz exposures on cerebral hemodynamics alterations. The results showed a significant and positive correlation between changes in Gz exposures and O2Hb concentration. This case report highlights that NIRS provides some valuable and sensitive indicators for the monitoring of cerebral hemodynamics during aerobatic flights exposed to multiple and high acceleration forces. To our knowledge, this first study quantifying cerebral oxygenation changes in aerobatics opens the way for the assessment of individual physiological responses and tolerance in pilots to repeated high Gz during real flights.Fresnel E, Dray G, Pla S, Jean P, Belda G, Perrey S. Cerebral oxygenation responses to aerobatic flight. Aerosp Med Hum Perform. 2021; 92(10):838-842.

Работа посвящена изучению особенностей системной гемодинамики у рожениц при возникновении акушерского кровотечения и выявлению прогностической роли гемодинамических параметров, используемых для оценки реакции системного кровообращения на потерю объема циркулирующей крови. Исследования проведены у 32 рожениц (средний возраст 29,7 ± 3,4 года, площадь поверхности тела — 1,96 ± 0,30 м2), у которых роды были осложнены акушерским кровотечением. В результате исследований было подтверждено преимущество использования показателей пульсового давления в качестве раннего детектора гиповолемии и тяжести кровопотери, которая часто компенсируется симпатическими рефлексами и скрывается за нормальными значениями артериального давления и центральными гемодинамическими показателями. При этом статистически достоверные изменения пульсового давления наблюдались начиная с кровопотери, которая составляла около/свыше 12 % объема циркулирующей крови.

The objective of this study is to describe the compensatory reserve index (CRI) baseline values in a healthy cohort of healthy pediatric patients and evaluate the existing correlation with other physiological parameters that influence compensatory hemodynamic mechanisms. CRI is a computational algorithm that has been broadly applied to non-invasively estimate hemodynamic vascular adaptations during acute blood loss. So far, there is a lack of baseline values from healthy individuals, which complicates accurately estimating the severity of the hemodynamic compromise. Additionally, the application of this technology in pediatric populations is limited to a few reports, highlighting a marked variability by age, weight, and other physiological parameters. The CRI of 205 healthy subjects from 0 to 60 years of age were prospectively evaluated from January to February 2020 at several public outpatient clinics in El Salvador; vital signs and sociodemographic data were also collected during this period. After data collection, baseline values were classified for each age group. Multiple correlation models were tested between the CRI and the other physiological parameters. CRI value varies significantly for each age group, finding for patients under 18 years old a mean value lower than 0.6, which is currently considered the lower normal limit for adults. CRI presents strong correlations with other physiological variables such as age, weight, estimated blood volume, and heart rate (R > 0.8, R2 > 0.6, p

Background: Individuals with left ventricular (LV) hypertrophy and elevated cardiac biomarkers in middle age are at increased risk for the development of heart failure with preserved ejection fraction. Prolonged exercise training reverses the LV stiffening associated with healthy but sedentary aging; however, whether it can also normalize LV myocardial stiffness in patients at high risk for heart failure with preserved ejection fraction is unknown. In a prospective, randomized controlled trial, we hypothesized that 1-year prolonged exercise training would reduce LV myocardial stiffness in patients with LV hypertrophy. Methods: Forty-six patients with LV hypertrophy (LV septum >11 mm) and elevated cardiac biomarkers (N-terminal pro-B-type natriuretic peptide [>40 pg/mL] or high-sensitivity troponin T [>0.6 pg/mL]) were randomly assigned to either 1 year of high-intensity exercise training (n=30) or attention control (n=16). Right-heart catheterization and 3-dimensional echocardiography were performed while preload was manipulated using both lower body negative pressure and rapid saline infusion to define the LV end-diastolic pressure-volume relationship. A constant representing LV myocardial stiffness was calculated from the following: P=S×[Exp {a (V–V 0 )}–1], where “P” is transmural pressure (pulmonary capillary wedge pressure – right atrial pressure), “S” is the pressure asymptote of the curve, “V” is the LV end-diastolic volume index, “V 0 ” is equilibrium volume, and “a” is the constant that characterizes LV myocardial stiffness. Results: Thirty-one participants (exercise group [n=20]: 54±6 years, 65% male; and controls (n=11): 51±6 years, 55% male) completed the study. One year of exercise training increased max by 21% (baseline 26.0±5.3 to 1 year later 31.3±5.8 mL·min –1 ·kg –1 , P P =0.0004), whereas there was no significant change in max in controls (baseline 24.6±3.4 to 1 year later 24.2±4.1 mL·min –1 ·kg –1 , P =0.986). LV myocardial stiffness was reduced (right and downward shift in the end-diastolic pressure-volume relationship; LV myocardial stiffness: baseline 0.062±0.020 to 1 year later 0.031±0.009), whereas there was no significant change in controls (baseline 0.061±0.033 to 1 year later 0.066±0.031, interaction P =0.001). Conclusions: In patients with LV hypertrophy and elevated cardiac biomarkers (stage B heart failure with preserved ejection fraction), 1 year of exercise training reduced LV myocardial stiffness. Thus, exercise training may provide protection against the future risk of heart failure with preserved ejection fraction in such patients. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03476785.

BACKGROUND Owing to its simplicity, speed, small incision, and low cost, peripheral blood collection is widely used in routine blood testing. However, there are certain differences between the detection results of peripheral and venous blood specimens. This investigation and analysis aimed to investigate and analyze the status and opinions of laboratory physicians on the application of peripheral blood for routine blood testing. METHODS A questionnaire was used to investigate and analyze the current status of laboratory physicians with regards to routine peripheral blood testing. The content of the questionnaire included the following aspects: the proportion of peripheral blood specimens, the difficulty of detecting peripheral blood, factors affecting the results of peripheral blood specimens, the proportion of the simultaneous detection of blood test and C-reactive protein (CRP), as well as the proportion and ideals of hypersensitive CRP (hs-CRP), which included a total of 10 re-examination rules. RESULTS Laboratory physicians from 410 hospitals participated in the investigation. The proportion of routine blood tests using peripheral blood specimens in the laboratory departments of tertiary hospitals was low (P=0.006). Difficulties in routine blood tests with peripheral blood specimens were dominated by insufficient blood volume (67.8%). The factors affecting the results of routine blood tests with peripheral blood specimens were dominated by the mixing method (86.6%). When abnormal results were determined by routine blood tests using peripheral blood specimens, they were retested most commonly by making slide smears (82.4%) or re-examined using the remaining peripheral blood (66.1%). The same rules for re-examination of peripheral and venous blood were applied in most medical institutions (86.1%). When the platelet count decreased in routine blood tests using peripheral blood samples, the most common measures included sample agglutination checks (88.5%), instrument alarm message checks (82.4%), and making slide smears for re-examination (73.6%). More laboratory physicians expected blood analyzers to be integrated instruments that could provide both routine blood and hs-CRP testing (80.5%). CONCLUSIONS There are numerous difficulties in routine blood testing using peripheral blood, and thus, more convenient and accurate blood analysis instruments should be developed.

Hypovolemia remains the leading cause of preventable death in trauma cases. Recent research has demonstrated that using noninvasive continuous waveforms rather than traditional vital signs improves accuracy in early detection of hypovolemia to assist in triage and resuscitation. This work evaluates random forest models trained on different subsets of data from a pig model (n = 6) of absolute (bleeding) and relative (nitroglycerin-induced vasodilation) progressive hypovolemia (to 20% decrease in mean arterial pressure) and resuscitation. Features for the models were derived from a multi-modal set of wearable sensors, comprised of the electrocardiogram (ECG), seismocardiogram (SCG) and reflective photoplethysmogram (RPPG) and were normalized to each subject.s baseline. The median RMSE between predicted and actual percent progression towards cardiovascular decompensation for the best model was 30.5% during the relative period, 16.8% during absolute and 22.1% during resuscitation. The least squares best fit line over the mean aggregated predictions had a slope of 0.65 and intercept of 12.3, with an $R^2$ value of 0.93. When transitioned to a binary classification problem to identify decompensation, this model achieved an AUROC of 0.80. This study: a) developed a global model incorporating ECG, SCG and RPPG features for estimating individual-specific decompensation from progressive relative and absolute hypovolemia and resuscitation; b) demonstrated SCG as the most important modality to predict decompensation; c) demonstrated efficacy of random forest models trained on different data subsets; and d) demonstrated adding training data from two discrete forms of hypovolemia increases prediction accuracy for the other form of hypovolemia and resuscitation.

Background Hidden blood loss (HBL) represents an important complication of unilateral biportal endoscopic (UBE) spine surgery. This study aimed to evaluate HBL and its possible risk factors among patients undergoing UBE surgery for lumbar degenerative diseases. Methods This multicentric retrospective study was conducted in 3 different medical centers between July 2020 and April 2021. Data of patients who underwent UBE surgery were extracted by electronic medical record system. The patient’s demographic characteristics and blood loss-related parameters were recorded. We calculated the amount of HBL and explored the association between patient’s characteristics and HBL using Pearson or Spearman correlation analysis. Multivariate linear regression analysis was conducted to identify independent risk factors of HBL. Results A total of 136 patients (55 females and 81 males, age range 43 to 74 years) were included in this study. A substantial amount of HBL (469.5 ± 195.3 ml, 57.6% of TBL, total blood loss) occurred following UBE surgery. Multiple linear regression analysis indicated that the risk factors of HBL were as follows: age (P = 0.000), number of fusion levels (P = 0.015), American Society of Anesthesiologists (ASA) classification (P = 0.046), surgery time (P = 0.017), patient’s blood volume (PBV, P = 0.026), total blood loss (TBL, P = 0.001), postoperative (i.e., day 2 or 3) hematocrit (Hct, P = 0.034), Hct loss (P = 0.005), and fibrinogen (P = 0.028). Conclusions A certain amount of HBL occurs in UBE surgery and cannot be ignored in daily clinical practice. The age, number of fusion levels, ASA classification, surgery time, PBV, TBL, postoperative Hct, Hct loss, and fibrinogen are independent risk factors for HBL.

The high-altitude maladaptation syndrome known as chronic mountain sickness (CMS) is characterized by polycythemia and is associated with proteinuria despite unaltered glomerular filtration rate. However, it remains unclear if indigenous highlanders with CMS have altered volume regulatory hormones. We assessed NH2-terminal pro-B-type natriuretic peptide (NT pro-BNP), plasma aldosterone concentration, plasma renin activity, kidney function (urinary microalbumin, glomerular filtration rate), blood volume, and estimated pulmonary artery systolic pressure (ePASP) in Andean males without ( n = 14; age = 39 ± 11 yr) and with ( n = 10; age = 40 ± 12 yr) CMS at 4,330 m (Cerro de Pasco, Peru). Plasma renin activity (non-CMS: 15.8 ± 7.9 ng/mL vs. CMS: 8.7 ± 5.4 ng/mL; P = 0.025) and plasma aldosterone concentration (non-CMS: 77.5 ± 35.5 pg/mL vs. CMS: 54.2 ± 28.9 pg/mL; P = 0.018) were lower in highlanders with CMS compared with non-CMS, whereas NT pro-BNP was not different between groups (non-CMS: 1394.9 ± 214.3 pg/mL vs. CMS: 1451.1 ± 327.8 pg/mL; P = 0.15). Highlanders had similar total blood volume (non-CMS: 90 ± 15 mL·kg−1vs. CMS: 103 ± 18 mL·kg−1; P = 0.071), but Andeans with CMS had greater total red blood cell volume (non-CMS: 46 ± 10 mL·kg−1vs. CMS: 66 ± 14 mL·kg−1; P < 0.01) and smaller plasma volume (non-CMS: 43 ± 7 mL·kg−1vs. CMS: 35 ± 5 mL·kg−1; P = 0.03) compared with non-CMS. There were no differences in ePASP between groups (non-CMS: 32 ± 9 mmHg vs. CMS: 31 ± 8 mmHg; P = 0.6). A negative correlation was found between plasma renin activity and glomerular filtration rate in both groups (group: r = −0.66; P < 0.01; non-CMS: r = −0.60; P = 0.022; CMS: r = −0.63; P = 0.049). A smaller plasma volume in Andeans with CMS may indicate an additional CMS maladaptation to high altitude, causing potentially greater polycythemia and clinical symptoms.

Background: We previously explained why acardiac twinning occurs in the first trimester. We raised the question why a sudden demised monochorionic twin beyond the first trimester does not lead to acardiac twinning. We argued that exsanguinated blood from the live twin would strongly increase the demised twins' vascular resistance, preventing its perfusion and acardiac onset. However, our current hypothesis is that perfusion of the demised twin does occur but that it is insufficient for onset of acardiac twinning. Methods: We analyzed blood pressures and flows in a vascular resistance model of a monochorionic twin pregnancy where one of the fetuses demised. The resistance model consists of a demised twin with a (former) placenta, a live twin and its placenta, and arterioarterial (AA) and venovenous placental anastomoses. We assumed that only twins with a weight of at least 33% of normal survived the first trimester and that exsanguination of more than 50% of its blood volume is fatal for the live twin. Results: At 20 weeks, only AA anastomoses with radii ≲1 mm keep the exsanguinated blood volume below 50%. Then, perfusion of the deceased body with arterial blood from the live fetus is about 5–40 times smaller than when that body was alive. Beyond 20 weeks, this factor is even smaller. At 14 weeks, this factor is at most 2. Conclusion: We hypothesize that this small perfusion flow of arterial blood prevents further growth of the deceased body and hence precludes onset of acardiac twinning.

Introduction: Hypertension is a degenerative disease. Those aged ?55 years are at risk for suffering from hypertension, previously blood pressure prehypertension before being diagnosed with hypertension occurred between the third and fifth decades. The World Health Organization reports as many as 839 million cases of hypertension, by 2025 this figure is expected to increase to 1.15 billion or around 29% of the world's total population, where female sufferers are more than 30% compared to male hypertension sufferers, namely 29%. One of the non-pharmacological treatments to treat hypertension is consuming cucumber. Methods: International and national literature searched through electronic media with keyword hints. Eight articles were selected, each of which represents an effectiveness of giving cucumber to reduce blood pressure and provides various information. Results: There was an effect of giving cucumber on reducing blood pressure in respondents. Discussion: One alternative that can be used to lower blood pressure is by consuming cucumber. The diuretic effect on cucumber causes the salt content in the blood to decrease. Reduced levels of salt that absorbs or retains water will reduce blood volume so that it can lighten the work of the heart in pumping blood, and eventually blood pressure will decrease. Conclusion: The conclusion based on the analysis that has been done is that cucumber is effective for lowering blood pressure.

Balloon pulmonary angioplasty (BPA) is used to treat patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH); the goal is to improve pulmonary perfusion. We aimed to evaluate lung perfusion blood volume (PBV) with haemodynamic and exercise-capacity parameters to assess the efficacy of BPA in the treatment of CTEPH. We retrospectively studied 33 patients over a 6-year period. DECT pulmonary angiography was performed before and after BPA. DECT provided iodine distribution maps; whole-lung and regional PBV images and quantification were generated using post-processing software. A mosaic pattern suggesting perfusion inhomogeneity is typical in CTEPH. Hypothetically, BPA treatment would promote homogenization that would be reflected in the calculated standard deviation. Lung perfusion images showed decreased heterogeneity after BPA. There was a significant difference before and after BPA in the whole-lung PBV and in the regional standard deviation for pulmonary arterial pressure (R = 0.37, p = 0.032 and R = 0.57, p = 0.006), pulmonary vascular resistance (R = 0.51, p = 0.023 and R = 0.60, p = 0.002), transtricuspid pressure gradient (R = 0.50, p = 0.0028 and R = 0.61, p = 0.0001), brain natriuretic peptide (R = 0.54, p = 0.0012 and R = 0.46, p = 0.0078), and 6-min walking distance (R = 0.59, p = 0.003 and R = 0.26, p = 0.14). The effects were especially pronounced after the first BPA procedure. Decreased lung heterogeneity may suggest BPA efficacy in treating CTEPH. After BPA treatment, improved lung PBV and improved regional standard deviation showed a strong positive correlation with haemodynamic parameters and exercise capacity, which also suggests that BPA is effective in treating CTEPH.

The clinical manifestation of shock is characterized by systemic circulatory disturbances andblood flow, hypoxic and metabolic disorders. The leading role in the pathogenesis of traumatic shock (the subtype of a hypovolemic shock), is assigned to the severity of the damaging effect, the time interval sufficient for the development of a pathophysiological response, mismatch between body tissue perfusion and the metabolic requirements, and impaired aerobic oxidation in tissues. The use of a comprehensive multicomponent intensive care strategy matching the pathophysiological changes is a difficult challenge for a critical care physician.The aim of the reviewis to demonstrate the specific features and sequence of events occurring in the body during the development of traumatic shock, the pattern of manifestations of clinical signs, and potential use of intensive therapy methods tailored to the pathophysiological responses in traumatic shock.Material. The information search was carried out in the PubMed and RSCI databases, among which 80 sources were finally selected, representing current therapeutic approaches, the results of scientific research and clinical guidelines related to the scope of this review.Results. The main stages of traumatic shock pathogenesis were reviewed. The basic patterns of cardiovascular and respiratory failure development were analyzed, the criteria of their severity were evaluated, and the complexity of the selection of intensive therapy was shown.Conclusion. Respiratory support, stabilization of cardiac and circulatory parameters and optimization of oxygen status are the most important components of treatment of patients with traumatic shock. Current methods of respiratory failure control allow to estimate promptly the severity of respiratory dysfunction, reveal the cause and correct existing disorders in an individualized way taking into account the better availability of mechanical ventilation. Replacement of circulating blood volume is aimed both at achieving hemodynamic effect and restoring the concentration of sources of oxygen carriers and plasma pro- and anticoagulant factors. The earliest and most comprehensive intensive therapy can improve the prognosis and outcome in patients with traumatic shock.

OBJECTIVE To quantify the volume of hidden blood loss (HBL) between conventional laparoscopic surgery (CLS) and laparoendoscopic single-site surgery (LESS) for ovarian cyst and to explore its risk factors. METHODS A total of 310 patients who underwent CLS or LESS were enrolled in this study. The Nadler formula and Gross formula were used to calculate each patient's estimated blood volume and total blood loss, multiple linear regression analysis was applied to identify the risk factors. RESULTS The HBL in LESS was more than in CLS (P = 0.000). Operative time (p = 0.015), pre-hematocrit (P = 0.002), pre-hemoglobin (P = 0.015), and pelvic adhesions (P = 0.037) were positively correlated with HBL in CLS. Intraoperative bleeding (P = 0.026), operative time (P = 0.000), pre-hematocrit (P = 0.042), CA125 (P = 0.047), and cyst volume (P = 0.012) were independent risk factors for HBL in LESS. CONCLUSION A large amount of HBL occurs in ovarian cystectomy surgery and cannot be ignored in clinical work; fully and correctly understanding HBL and exploring its causes can ensure the safety and improve the prognosis of patients.

BACKGROUND Source plasma (SP) is the primary starting material for 87% of plasma-derived medicinal products globally. Plasmavigilance is a program designed to collect, analyze, and monitor donor adverse events (AEs) across the SP collection industry. Donor retention depends on donors having a safe and satisfactory experience. This study analyzes AE rates and SP donor characteristics that may be predictors of an AE. STUDY DESIGN AND METHODS Donation data for 1.1 million donors making 12,183,182 SP donations over a 4-month period were analyzed. This represented approximately 72% of the donations collected by the U.S. plasma industry. The Standard for Recording Donor Adverse Events was used for AE definitions and classifications. RESULTS The overall AE rate was 15.85/104 donations. The two AEs with the highest rates were Hypotensive and Phlebotomy events (8.32 and 5.91/104 donations, respectively). Females had higher overall AE rates than males (25.76 vs. 9.85/104 donations), and first-time donors had higher overall AE rates than repeat donors (136.66 vs. 12.37/104 donations). Weight, body mass index, age, and pre-donation estimated blood volume also were predictors of AE. DISCUSSION SP donors have low AE rates with 90% being events classified as Hypotensive or Phlebotomy. Special attention and mitigation strategies should be directed to donors who are young, lightweight (between 100 and 124 pounds), female, or first-time donors to further reduce the incidence of AE, continue to ensure the donor has a safe experience, and facilitate donor retention.

Background The amount of intracranial blood is a strong predictor of poor outcome after subarachnoid hemorrhage (SAH). Here, we aimed to measure iron concentrations in the cerebral white matter, using the cerebral microdialysis (CMD) technique, and to associate iron levels with the local metabolic profile, complications, and functional outcome. Methods For the observational cohort study, 36 patients with consecutive poor grade SAH (Hunt & Hess grade of 4 or 5, Glasgow Coma Scale Score ≤ 8) undergoing multimodal neuromonitoring were analyzed for brain metabolic changes, including CMD iron levels quantified by graphite furnace atomic absorption spectrometry. The study time encompassed 14 days after admission. Statistical analysis was performed using generalized estimating equations. Results Patients were admitted in a poor clinical grade (n = 26, 72%) or deteriorated within 24 h (n = 10, 28%). The median blood volume in the subarachnoid space was high (SAH sum score = 26, interquartile range 20–28). Initial CMD iron was 44 µg/L (25–65 µg/L), which significantly decreased to a level of 25 µg/L (14–30 µg/L) at day 4 and then constantly increased over the remaining neuromonitoring days (p p = 0.04) but not with the hemorrhage load in the subarachnoid space (p = 0.8). In patients developing vasospasm, the CMD iron load was higher, compared with patients without vasospasm (Wald-statistic = 4.1, degree of freedom = 1, p = 0.04), which was not true for delayed cerebral infarction (p = 0.4). Higher iron concentrations in the brain extracellular fluid (34 µg/L, 36–56 µg/L vs. 23 µg/L, 15–37 µg/L) were associated with mitochondrial dysfunction (CMD lactate to pyruvate ratio > 30 and CMD-pyruvate > 70 µM/L, p p > 0.5). Conclusions This study suggests that iron accumulates in the cerebral white matter in patients with poor grade SAH. These findings may support trials aiming to scavenger brain extracellular iron based on the hypothesis that iron-mediated neurotoxicity may contribute to acute and secondary brain injury following SAH.

Key points Humans suffering from polycythaemia undergo multiple circulatory adaptations including changes in blood rheology and structural and functional vascular adaptations to maintain normal blood pressure and vascular shear stresses, despite high blood viscosity. During exercise, several circulatory adaptations are observed, especially involving adrenergic and non-adrenergic mechanisms within non-active and active skeletal muscle to maintain exercise capacity, which is not observed in animal models. Despite profound circulatory stress, i.e., polycythaemia, several adaptations can occur to maintain exercise capacity, therefore making early identification of the disease difficult without overt symptomology. Pharmacological treatment of the background heightened sympathetic activity may impair the adaptive sympathetic response needed to match local oxygen delivery to active skeletal muscle oxygen demand and therefore inadvertently impair exercise capacity. Abstract Excessive haematocrit and blood viscosity can increase blood pressure, cardiac work and reduce aerobic capacity. However, past clinical investigations have demonstrated that certain human high-altitude populations suffering from excessive erythrocytosis, Andeans with chronic mountain sickness, appear to have phenotypically adapted to life with polycythaemia, as their exercise capacity is comparable to healthy Andeans and even with sea level inhabitants residing at high altitude. By studying this unique population, which has adapted thru natural selection, this study aimed to describe how humans can adapt to life with polycythaemia. Experimental studies included Andeans with (n = 19) and without (n = 17) chronic mountain sickness, documenting exercise capacity, and characterizing the transport of oxygen thru blood rheology, including haemoglobin mass, blood and plasma volume & blood viscosity, cardiac output, blood pressure and changes in total and local vascular resistances thru pharmacological dissected of α-adrenergic signalling pathways within non-active and active skeletal muscle. At rest, Andeans with chronic mountain sickness had a substantial plasma volume contraction, which alongside a higher red blood cell volume, caused an increase in blood viscosity yet similar total blood volume. Moreover, both morphological and functional alterations in the periphery normalized vascular shear stress and blood pressure despite high sympathetic nerve activity. During exercise, blood pressure, cardiac work and global oxygen delivery increased similar to healthy Andeans but were sustained by modifications in both non-active and active skeletal muscle vascular function. These findings highlight widespread physiological adaptations that can occur in response to polycythaemia, which allow the maintenance of exercise capacity. This article is protected by copyright. All rights reserved.

Background Through venous contraction, norepinephrine (NE) increases stressed blood volume and mean systemic pressure (Pms) and exerts a “fluid-like” effect. When both fluid and NE are administered, Pms may not only result from the sum of the effects of both drugs. Indeed, norepinephrine may enhance the effects of volume expansion: because fluid dilutes into a more constricted, smaller, venous network, fluid may increase Pms to a larger extent at a higher than at a lower dose of NE. We tested this hypothesis, by mimicking the effects of fluid by passive leg raising (PLR). Methods In 30 septic shock patients, norepinephrine was decreased to reach a predefined target of mean arterial pressure (65–70 mmHg by default, 80–85 mmHg in previously hypertensive patients). We measured the PLR-induced increase in Pms (heart–lung interactions method) under high and low doses of norepinephrine. Preload responsiveness was defined by a PLR-induced increase in cardiac index ≥ 10%. Results Norepinephrine was decreased from 0.32 [0.18–0.62] to 0.26 [0.13–0.50] µg/kg/min (p p p Conclusions Norepinephrine enhances the Pms increase induced by PLR. These results suggest that a bolus of fluid of the same volume has a greater haemodynamic effect at a high dose than at a low dose of norepinephrine during septic shock.

BACKGROUND & AIMS: The aim was to measure fractional hepatic blood volume (HBV) and hepatic blood flow (HBF) before and after a meal in patients with cirrhosis (n = 7) and healthy persons (n = 6).METHODS: Catheters were placed in a radial artery and a hepatic vein for blood sampling and a peripheral vein for indocyanine green (ICG) infusion. A 6-min positron emission tomography (PET) liver scan was performed after inhalation of 1000 MBq 15O-CO and repeated after ingestion of a standard meal. HBV was calculated as the 15O-CO concentration in liver tissue (PET) divided by that in arterial blood. HBF was calculated from ICG infusion rate and arterial and hepatic venous blood concentrations according to Fick's principle.RESULTS: Mean fasting HBV was 14 mL blood/100 mL liver tissue in patients with cirrhosis and 21 mL blood/100 mL liver tissue in healthy subjects (p CONCLUSIONS: Fasting HBV was lower in patients with cirrhosis and did not decrease postprandially as it did in the healthy controls although the HBF increased equally. Patients with cirrhosis thus have a disturbed hemodynamic response to normo-physiological changes such as a meal.

Purpose: assessment of functional indices of external respiration, the level of physical health and the general state of the autonomic nervous system of university students. Material: There were examined 192 students aged 18-21 years. All examined were divided into groups depending on gender, age and future profession. Anthropometric indices and parameters of the circulatory system were studied. Spirometer was used to measure the respiratory system functional indices. An express assessment of physical health level was made. Index of functional changes, the Kerdo vegetation index, the orthostatic index, and the Skibinskaya index were calculated. Stange test, Hench test and Martin-Kushelevsky’s test were conducted. Results: The results are showed that the minute blood volume was higher in all examined young girls, whereas in young boys designers and pharmacists aged 17-18 years and 19-21 years, respectively it was lower than due values. Similar data were obtained after the Ruffier test (dynamic load tolerance). The index of vital lung capacity (VC) was significantly lower than due values in all students. The parameters of maximal pulmonary ventilation indicated good functional ability of the external respiration apparatus in young boys. This index was higher than that of young girls and exceeded due values. The adaptation capacities of the student body (index of functional changes (IFI)) were at a satisfactory level. The indices of physical health level of all students had average values. Conclusions: Studies have revealed the most characteristic shifts of cardiorespiratory system indices, which are most expressed in students. Cardiorespiratory system shifts are caused by the influence of a complex of factors: increased academic load; requirements for the professionalization process continuity; performance of various structured activity types, manipulations, a high degree of responsibility. Increased pulse rate and minute blood volume; prevalence of the hyperkinetic type of blood circulation self-regulation at rest; irrational cardiovascular system response to dosed physical load; positive value of the Kerdo vegetation index; decreased ventilatory lung capacity and reserve capacity of cardiorespiratory system; tension of adaptation mechanisms; average level of physical health were recorded in students.

To offer a practical guide for the presurgical and anesthetic management of pheochromocytomas and sympathetic paragangliomas (PGLs). This protocol was based on a comprehensive review of the literature and on our own multidisciplinary team’s experience from managing pheochromocytoma and sympathetic PGLs at a referral center. Patients with pheochromocytomas and sympathetic paragangliomas (PGLs) may develop potentially life-threatening complications, especially during surgical procedures. A complete biochemical, radiological, genetic, and cardiological assessment is recommended in the preoperative stage as it provides an evaluation of the risk of surgical complications and malignancy, allowing individualization of the presurgical treatment. Treatment with α-blockade and proper volume expansion in the preoperative stage significantly reduces the perioperative morbidity. During surgery, the anesthesiologist should look for a deep anesthetic level that inhibits the cardiovascular effects of catecholamines to minimize the risk of intraoperative complications. An optimal presurgical evaluation of pheochromocytomas/ sympathetic PGL requires a multidisciplinary approach, including a complete hormonal, radiological, cardiac, genetic, and functioning evaluation in most cases. A proper preoperative evaluation in combination with strict blood pressure and heart rate control, and blood volume status optimization, will significantly reduce the risk of intraoperative and perioperative complications. In those patients who unfortunately develop intraoperative complications, the role of the anesthesiologist is essential since the selection of the appropriate management has a direct impact on morbimortality reduction.

Premature infants are at high risk of haemorrhage and thrombosis. Our understanding of the differences between the neonatal and adult haemostatic system is evolving. There are several limitations to the standard coagulation tests used in clinical practice, and there is currently a lack of evidence to support many of the transfusion practices in neonatal medicine. The evaluation of haemostasis is particularly challenging in neonates due to their limited blood volume. The calibrated automated thrombogram (CAT) is a global coagulation assay, first described in 2002, which evaluates both pro- and anti-coagulant pathways in platelet-rich or platelet-poor plasma. In this review, the current applications and limitations of CAT in the neonatal population are discussed.Conclusion: CAT has successfully elucidated several differences between haemostatic mechanisms in premature and term neonates compared with adults. Moreover, it has been used to evaluate the effect of a number of haemostatic drugs in a pre-clinical model. However, the lack of evidence of CAT as an accurate predictor of neonatal bleeding, blood volume required and the absence of an evidence-based treatment algorithm for abnormal CAT results limit its current application as a bedside clinical tool for the evaluation of sick neonates. What is Known:• The Calibrated automated thrombogram (CAT) is a global coagulation assay which evaluates pro- and anti-coagulant pathways.• CAT provides greater information than standard clotting tests and has been used in adults to evaluate bleeding risk. What is New:• This review summarises the physiological differences in haemostasis between neonates and adults described using CAT.• The haemostatic effect of several drugs has been evaluated in neonatal plasma using CAT.

Inroduction. Systemic inflammatory response (SIR) is an obligatory manifestation of operational stress affecting the functional status of patients, which is important to consider in persons with comorbid pathology.Aim. Evaluation of the relationship between pulmonary volemia and SIR indicators in patients with comorbidity of chronic obstructive pulmonary disease (COPD) and ischemic heart disease (IHD) after coronary artery bypass grafting (CABG).Materials and methods. The study included 76 IHD patients aged 53 to 77 years who underwent CABG. Among the surveyed, 2 groups were identified: 39 patients with IHD and 37 – with a combination of IHD and COPD. The following indices were measured by transpulmonary thermodilution: pulmonary blood volume (PBV), extravascular lung water index (EVLWI), pulmonary vascular permeability index (PVPI), pulmonary shunt fraction (Qs/Qt). Determined the concentration in the blood of interleukin 6 and 10 (IL-6, IL-10), tumor necrosis factor-alpha (TNF-α); transforming growth factor-beta1 (TGFβ1), NLR - the ratio of neutrophils to lymphocytes; PLR – the ratio of platelets to lymphocytes.Results. The most pronounced disturbances in the water balance of the lungs, manifested by an increase in EVLWI, PVPI and Qs/Qt were recorded in patients with comorbidity of COPD and IHD immediately after withdrawal from cardiopulmonary bypass. The PBV level at all measurement points in patients with COPD was lower, which indicated the prevalence of right ventricular failure. SIR on operational stress in this category of patients was manifested by the discoordination of the cytokine profile: a sharp increase in the concentration of IL-6 and IL-10 against the background of a relatively stable level of TNFα and TGF-β1, as well as an increase in NLR and PLR.Conclusion. The unidirectional response of pulmonary volemia and SIR indicators to operational stress indicates the pathophysiological relationship of the studied phenomena.

We demonstrated pulmonary arteriolar blood flow-mediated CO2 gas excretion in rabbit lungs. The shear stress stimulation produced CO2 gas in cultured human endothelial cells of pulmonary arterioles via the activation of F1/Fo ATP synthase. To confirm the findings in human subjects undergoing the operation with heart–lung machines, we aimed to evaluate the effects of a stepwise switch, from a partial to a complete cardiopulmonary bypass, of the circulatory blood volume (BV, 100% = 2.4 × cardiac index), on the end-expiratory CO2 pressure (PetCO2), maximal flow velocity in the pulmonary artery (Max Vp), the inner diameter (ID) of pulmonary artery, pulmonary arterial CO2 pressure (P mix v CO2), pulmonary arterial O2 pressure (P mix v O2), hematocrit (Hct), pH, the concentration of HCO3−, and base excess (BE) in mixed venous blood in 9 patients with a mean age of 72.3 ± 3.4 years. In addition, the effects of the decrease in Hct infused with physiological saline solution (PSS) on PetCO2 were investigated in the human subjects. An approximately linear relationship between the PetCO2 and Max Vp was observed. The pumping out of 100% BV produced little or no change in the Hct, pH, P mix v CO2, and P mix v O2, respectively. The hemodilution produced by intravenous infusion of PSS caused a significant decrease in the Hct, but not in the PetCO2. In conclusion, another route of CO2 gas excretion, independent of red blood cells, may be involved in human lungs.

Cerebrovascular autoregulation (CA) is a protective mechanism that enables the cerebral vasculature to automodulate tone in response to changes in cerebral perfusion pressure to ensure constant levels of cerebral blood flow (CBF) and oxygen delivery. CA can be impaired after neurological injury and contributes to secondary brain injury. In this study, we report novel impedance indices using trans-ocular brain impedance (TOBI) during controlled systemic hemorrhage and hypotension to assess CA in comparison with pressure reactivity index (PRx). Yorkshire swine were instrumented to record intracranial pressure (ICP), mean arterial pressure (MAP), and CBF. TOBI was recorded using electrocardiographic electrodes placed on the closed eyelids. Impedance changes (dz) were recorded in response to introducing an alternating current (0.4 mA) through the electrodes. MAP, ICP, and CBF were also measured. Animals were subjected to a controlled hemorrhage to remove 30–40% of each animal’s total blood volume over 25–35 min. Hemorrhage was titrated to reach an MAP of approximately 35 mm Hg and end-tidal carbon dioxide above 28 mm Hg. PRx was calculated as a moving Pearson correlation between MAP and ICP. TOBI indices were calculated as the amplitude of the respiratory-induced changes in dz. DZx was calculated as a moving Pearson correlation between dz and MAP. TOBI indices (dz and DZx) were compared with hemodynamic indicators and PRx. dz was shown to be highly correlated with MAP, ICP, cerebral perfusion pressure, and CBF (r = − 0.823, − 0.723, − 0.813, and − 0.726), respectively (p

Retrospective, multicenter comparative. Our purpose was to compare early onset scoliosis (EOS) patients treated with ultra-low, low, and high implant density constructs when undergoing conversion to definitive fusion. Larson et al. demonstrated that implant density (ID) at fusion does not correlate with outcomes in the treatment of adolescent idiopathic scoliosis, but did not address growth-friendly graduates. EOS patients treated with growth-friendly constructs converted to fusion between 2000 and 2017 were reviewed from a multicenter database. ID was defined as number of pedicle screws, hooks, and sublaminar/bands per level fused. Patients were divided into ultra-low ID (

BACKGROUND Apheresis procedures require adequate vascular access to achieve optimal inlet flow rates. While central lines provide such access, their placement and use are associated with risks; some of these risks are minimized if peripheral intravenous access can be established. However, peripheral intravenous access is associated with challenges in the pediatric setting. Research indicates that midline catheters reduce the use of CVADs and their associated risks. The use of midline catheters for apheresis has been reported recently in adults, but no studies have been published on their use in children. Thus, the purpose of this study was to evaluate the use of midline catheters for apheresis in the pediatric setting. METHODS A retrospective observational study was conducted to evaluate the safety and efficacy of midline catheters in subjects who underwent apheresis at a pediatric hospital from April 2018 to August 2020. Demographic data, clinical data (diagnosis, procedure, catheter size, body mass), and outcome data (inlet flow rate, total blood volume [TBV] processed, procedure time, and cell counts) were collected. RESULTS Eighteen subjects received a total of 100 midline catheters for 73 apheresis procedures. Inlet flow rates ranged from 45 to 80 mL/min, TBV ranged from 2872 to 20 000 mL, and procedure time ranged from 1.25 to 7 hours. Inlet flow rates met or exceeded the recommended inlet flow rates for apheresis in children and adults (P

Total nucleated cell (TNC) and CD34+ cell doses are considered among the most important parameters when assessing the suitability of a human leukocyte antigen-matched cord blood unit (CBU) for allogeneic hematopoietic stem cell transplantation (HSCT). Cord blood banks therefore frequently select CBUs for cryopreservation based on pre-process TNC content. However, cell loss during processing can lead to a significant quantity of CBUs that do not meet desired post-process quality criteria, and such grafts are less likely to be selected by transplant centers for HSCT. Here the authors present a multi-parameter linear regression (MLR) model capable of identifying CBUs that would process poorly, despite meeting established pre-process TNC and CD34+ quality thresholds.Historically processed CBUs were graded from A+ to D depending on post-process cell content, and the utilization rate of each grade category was examined. Eight pre-process predictors of post-process cell content were used to train the MLR model, including red blood cell (RBC) content; CBU volume; age of CBU when received; and TNC constituent cell subsets. The selection efficacy of this model was then compared to that of methods conventionally used to select CBUs for processing, with receiver operating characteristic (ROC) and mean inventory quality analysis forming the basis of assessment.Within the Anthony Nolan Cell Therapy Centre, CBUs graded 'D' accounted for 37% of processing expenditures despite providing only 11% of grafts shipped for HSCT. The MLR model significantly improved pre-process identification of 'D' grade CBUs relative to thresholds based primarily on CD34+ cell content (P0.0001) and TNC content (P0.0001). At a comparable financial investment, this translated to a banked graft inventory of significantly higher quality than that produced by CD34+ (+8.8% mean increase, P = 0.007) and TNC (+9.9% mean increase, P = 0.010) selection methods.A predictive modelling approach to pre-process CBU selection is a simple and effective means to increase graft inventory quality and potentially future graft utilization, at no additional financial investment.

Background Angiogenesis is prominent in metastatic renal cell carcinoma (mRCC). We compared two angiogenesis assessment methods: dynamic contrast-enhanced computed tomography (DCE-CT)-derived blood volume (BV) and blood flow (BF) and core biopsy microvessel density (MVD). Methods As planned in DaRenCa Study-1 study, DCE-CT and core biopsy were performed from the same tumour/metastasis at baseline. MVD was assessed by CD34 immunostaining in tumour (CD34-indexT) or tumour including necrosis (CD34-indexTN). BV and BF were assessed using the DCE-CT software. Overall survival (OS) and progression-free survival (PFS) were assessed by Kaplan-Meier analysis. Spearman coefficient (rho) tested the correlation between MVD and BV, BF, or CT density (HU). Results At baseline, 25 patients had analysable scans and tissue. BVdeconv, BVPatlak, and BFdeconv > median were associated with favourable OS (43.2 versus 14.6 months, p = 0.002; 31.6 versus 20.2 months, p = 0.015; and 31.6 versus 24.5 months, p = 0.019). CD34-indexT and CD34-indexTN did not correlate with age (p = 0.543), sex (p = 0.225), treatment (p = 0.848), International mRCC Database Consortium category (p = 0.152), synchronous versus metachronous metastatic disease (p = 0.378), or tumour volume (p = 0.848). CD34-indexT or CD34-indexTN > median was not associated with PFS (p = 0.441 and p = 0.854, respectively) or OS (p = 0.987 and p =0.528, respectively). CD34-indexT or CD34-indexTN was not correlated with BV, BF, or HU (rho 0.20–0.26). Conclusions Differently from MVD, DCE-CT-derived BV and BF had prognostic impact and may better reflect angiogenesis in mRCC. Trial registration NCT01274273

Background Although relationship between dialysate sodium concentration and hemodynamic stability has been well studied over the years, outcomes of absolute blood volume (ABV) maintenance and vascular refilling volume (Vref ) modifications were not included, as its analysis has not been easily accessible to direct investigation. However, recent studies report a simple and feasible methodology to assess ABV and Vref during hemodialysis (HD) treatments. It is the aim of this study to analyze whether sodium concentration in dialysate modifies ABV drop and Vref . Methods The study was performed in 19 patients under HD. During three different sessions, sodium concentration in dialysate was randomized to three different profiles: low sodium concentration (LNa, 138 mEq/L), neutral sodium concentration (NNa, 140 mEq/L), and high sodium concentration (HNa, 143 mEq/L). ABV and Vref were calculated using Kron et al methodology. Results Predialysis values of the measured parameters showed similar results for the three profiles. Sodium concentration showed an effect on ABV drop, Vref, and vascular refilling fraction (Fref ). Pair-wise comparison revealed mean ABV decreased 0.21 L less when using HNa profile versus LNa profile (p = 0.027), a mean Vref increase of 0.39 L (p = 0.038), and a mean Fref increase of 9.94% (p = 0.048). Conclusions This study shows that the use of HNa profiles increases Vref and Fref and reduces ABV drop during dialysis treatments when compared to LNa profiles.