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Journal of Cardiac Failure Sep 2022The role of blood volume (BV) expansion vs a change in vascular compliance in worsening heart failure (HF) remains under debate. We aimed to assess the relationship...
BACKGROUND
The role of blood volume (BV) expansion vs a change in vascular compliance in worsening heart failure (HF) remains under debate. We aimed to assess the relationship between BV and resting and stress hemodynamics in worsening HF and to further elucidate the significance of BV in cardiac decompensation.
METHODS AND RESULTS
Patients with worsening HF underwent radiolabeled indicator-dilution BV analysis and cardiac catheterization. Intravascular volumes and resting/stress hemodynamics were recorded. Provocative stress maneuvers included change in systolic blood pressure (ΔSBP) from lying to standing and Valsalva and intracardiac pressure changes with leg raise. Correlation between BV and invasive hemodynamics were assessed by linear regression. Of 27 patients with worsening HF, patients' characteristics included mean age 61 ± 12 years, 70% male, 19% Black, and mean ejection fraction 29% ± 15%. Of the patients, 13 (48%) had hypervolemia as measured by total BV, which weakly correlated with ΔSBP by position (R = 0.009) and Valsalva (R = 0.003) and with right atrial (R = 0.049) and pulmonary capillary wedge (R = 0.047) pressure changes during leg raise.
CONCLUSIONS
In patients with worsening HF, BV mildly correlated with intracardiac pressures at rest. Provocative maneuvers intended to test vascular compliance did not correlate with BV, indicating that compliance may serve as a stand-alone metric in HF.
Topics: Aged; Blood Volume; Female; Heart Failure; Hemodynamics; Humans; Male; Middle Aged; Pulmonary Wedge Pressure; Stroke Volume
PubMed: 35483537
DOI: 10.1016/j.cardfail.2022.04.004 -
Acta Anaesthesiologica Scandinavica Feb 2021Haemodynamic studies in children are rare and most studies have included few subjects in the youngest age group. Haemodynamic variables need to be indexed to establish a... (Observational Study)
Observational Study
BACKGROUND
Haemodynamic studies in children are rare and most studies have included few subjects in the youngest age group. Haemodynamic variables need to be indexed to establish a reference of normality that is valid in all populations. The traditional way to index haemodynamic variables with body surface area (BSA) is complicated in young children due to its non-linear relationship with body weight (BW). We examined several haemodynamic variables in children by indexing them with BSA and BW.
METHODS
A single-centre, observational cohort study comparing non-indexed and indexed haemodynamic variables in children undergoing heart surgery (divided into three weight groups: 1-5 kg, >5-10 kg and >10-15 kg).
RESULTS
A total of 68 children were included in this study, mean age 11.1 months ± 11.1 month (range 0 to 43 months). All haemodynamic variables, cardiac output (CO), stroke volume (SV), total end-diastolic volume (TEDV), central blood volume (CBV) and active circulation volume (ACV), increased with weight without indexing (P < .05). Indexing variables with BW produced a more linear relationship for all haemodynamic variables between weight groups than BSA. The mean BSA-indexed haemodynamic values were CI 3.5 ± 1.1 L/min/m and SVI 27.3 ± 8.9 ml/min/m . The mean BW-indexed haemodynamic values were CI 180 ± 50 ml/min/kg and SVI 1.34 ± 0.38 ml/kg. Blood volume variables indexed with BW were TEDV 12.0 ± 2.8 ml/kg, CBV 21.3 ± 6.6 ml/kg and ACV 70.3 ± 15.2 ml/kg.
CONCLUSIONS
Indexing haemodynamic variables with BW produces a more appropriate body size-independent scale in young children than BSA.
SUMMARY STATEMENT
In this study, we studied indexing of haemodynamic variables and estimation of blood volumes in young children undergoing corrective heart surgery using an indicator dilution technology.
Topics: Body Surface Area; Cardiac Output; Child; Child, Preschool; Cohort Studies; Humans; Infant; Infant, Newborn; Stroke Volume
PubMed: 33015826
DOI: 10.1111/aas.13720 -
The American Journal of Nursing Nov 2023Infection in an immunocompromised person can be a life-threatening emergency. Collection of blood culture specimens is an important method for detecting organisms when...
Infection in an immunocompromised person can be a life-threatening emergency. Collection of blood culture specimens is an important method for detecting organisms when infection is suspected. One aspect of proper blood culture collection is obtaining an accurate blood volume in the sample in accordance with the blood culture bottle manufacturer's recommendation. Underfilling the culture bottle can lead to false-negative results, while overfilling it can lead to false-positive results. At our institution, the Department of Laboratory Medicine (DLM) routinely monitors blood culture bottle volumes and notifies the nursing department of underfill/overfill events, which the department then reviews. Over several years, the DLM and the nursing department noted an increase in these events. A clinical nurse specialist and three staff nurses in the oncology/critical care services area partnered with the DLM to determine why. Upon investigation, two key issues-imprecise weighing of bottles and staff misunderstanding of the proper blood culture collection technique-were discovered. In response, the nursing standard of practice and guidance on the DLM webpage were updated and nursing education was performed. As a result, underfill/overfill events decreased by 71% in a little over a year.
Topics: Humans; Blood Culture; Critical Care; Health Facilities; Blood Volume
PubMed: 37882404
DOI: 10.1097/01.NAJ.0000995368.45516.ec -
Investigative Radiology Sep 2022We propose a method of quantitatively measuring drug-induced microvascular volume changes, as well as drug-induced changes in blood oxygenation using calibrated blood... (Observational Study)
Observational Study
OBJECTIVES
We propose a method of quantitatively measuring drug-induced microvascular volume changes, as well as drug-induced changes in blood oxygenation using calibrated blood oxygen level-dependent magnetic resonance imaging (MRI). We postulate that for MRI signals there is a contribution to R2* relaxation rates from static susceptibility effects of the intravascular blood that scales with the blood volume/magnetic field and depends on the oxygenation state of the blood. These may be compared with the effects of an intravascular contrast agent. With 4 R2* measurements, microvascular blood volume (MBV) and tissue oxygenation changes can be quantified with the administration of a vasoactive drug.
MATERIALS AND METHODS
The protocol examined 12 healthy rats in a prospective observational study. R2* maps were acquired with and without infusion of adenosine, which increases microvascular blood flow, or dobutamine, which increases myocardial oxygen consumption. In addition, R2* maps were acquired after the intravenous administration of a monocrystalline iron oxide nanoparticle, with and without adenosine or dobutamine.
RESULTS
Total microvascular volume was shown to increase by 10.8% with adenosine and by 25.6% with dobutamine ( P < 0.05). When comparing endocardium versus epicardium, both adenosine and dobutamine demonstrated significant differences between endocardial and epicardial MBV changes ( P < 0.05). Total myocardial oxygenation saturation increased by 6.59% with adenosine and by 1.64% with dobutamine ( P = 0.27). The difference between epicardial and endocardial oxygenation changes were significant with each drug (adenosine P < 0.05, dobutamine P < 0.05).
CONCLUSIONS
Our results demonstrate the ability to quantify microvascular volume and oxygenation changes using calibrated blood oxygen level-dependent MRI, and we demonstrate different responses of adenosine and dobutamine. This method has clinical potential in examining microvascular disease in various disease states without the administration of radiopharmaceuticals or gadolinium-based contrast agents.
Topics: Adenosine; Animals; Blood Volume; Coronary Circulation; Dobutamine; Rats; Vasodilator Agents
PubMed: 35438656
DOI: 10.1097/RLI.0000000000000871 -
International Journal of Nephrology and... 2021Volume management in hemodialysis (HD) requires the ability to assess volume status objectively and determine treatment strategies that achieve euvolemia without...
PURPOSE
Volume management in hemodialysis (HD) requires the ability to assess volume status objectively and determine treatment strategies that achieve euvolemia without compromising hemodynamic stability. The aim of this study was to compare dialysis with and without blood volume-controlled ultrafiltration (UF) in combination with body composition monitoring, and to evaluate indicators for adequate dialysis (Kt/V), ultrafiltration volume, fluid status, and the occurrence of intradialytic morbid events (IME).
PATIENTS AND METHODS
Patients undergoing hemodialysis or on-line hemodiafiltration with support of a blood volume monitor (BVM) - a feedback control device integrated into the 5008 and 6008 HD systems - were enrolled. Patients received treatment for four weeks using the 6008 CAREsystem and the BVM (6008+). Data on dialysis dose (Kt/V), UF volume and predialysis fluid status were documented. This data was also documented retrospectively for four weeks with (5008+) and without (5008-) the use of the BVM with the 5008 system. Comparisons were analyzed using linear mixed models.
RESULTS
Twenty-four patients were enrolled. Kt/V was unaffected by blood volume-controlled UF (5008- vs 5008+: =0.230) and was equally achieved with both HD systems (5008+ vs 6008+: =0.922). The UF volume and fluid status achieved were comparable, independent of the use of UF control with BVM (5008- vs 5008+; UF volume: =0.166; fluid overload: =0.390) or the HD system (5008+ vs 6008+: UF volume: =0.003; fluid overload: =0.838), except for UF volume being higher in the 6008+ phase. IMEs occurred in less than 3% of treatments, with no difference between study phases.
CONCLUSION
This study demonstrates that a clinical approach to kidney replacement therapy that tracks volume status and manages intradialytic fluid removal by blood volume-controlled UF delivers adequate dialysis without compromising fluid removal. It maintains volume status and ensures low incidence of IMEs.
PubMed: 34511978
DOI: 10.2147/IJNRD.S319911 -
PloS One 2020In this study, the physiological values of volumes of plasma, cells, total blood and the F blood factors were identified in 24 adult tree shrews (Tupaia belangeri; 12...
In this study, the physiological values of volumes of plasma, cells, total blood and the F blood factors were identified in 24 adult tree shrews (Tupaia belangeri; 12 male and 12 female; average BW of 123.9±19.19 g). The two-compartment model method of Evans Blue dye was used to obtain the plasma volume and the venous hematocrit was measured by microhematocrit method. To establish the relationship between body weight (BW) and blood volume of tree shrews, We performed linear fitting for these two datasets. Results were analyzed according to gender and weight (<120g vs.>120g). Statistical significance was assessed using the unpaired student t test and one-way ANOVA. The average volumes per 100g body weight of plasma, red blood cell (RBC) and total blood were 5.42±0.543, 3.24±0.445, and 8.66±0.680ml respectively. The mean body hematocrit, cardiac hematocrit, jugular vein hematocrit, femoral vein hematocrit, and tail vein hematocrit was 37.43±4.096, 39.72±3.219, 43.04±4.717, 40.84±3.041, and 38.71±3.442% respectively. The F cardiac was 0.94±0.072, F jugular vein 0.88±0.118, F femoral vein 0.92±0.111, and the F tail vein 0.97±0.117. Blood volume (ml) was 85.89103×BW (kg). This is the first study to provide the parameters of plasma volume, cell volume, total blood volume and F factor and a baseline for future research on blood physiology of tree shrews.
Topics: Animals; Blood Volume; Body Weight; Cell Size; Female; Hematocrit; Male; Plasma Volume; Tupaiidae
PubMed: 32881864
DOI: 10.1371/journal.pone.0234835 -
PloS One 2022Current methods for identification of oxygenator clotting during prolonged extracorporeal life support include visual inspection, evaluation of oxygenator resistance and...
Current methods for identification of oxygenator clotting during prolonged extracorporeal life support include visual inspection, evaluation of oxygenator resistance and oxygen exchange performance, and assessment of clotting-related laboratory parameters. However, these observations do not provide a quantitative assessment of oxygenator clot formation. By measuring changes in the dynamic oxygenator blood volume this study aimed to evaluate the relation to oxygenator resistance and oxygen transfer performance. Sixty-seven oxygenators were studied during adult extracorporeal life support. Oxygenator blood volume, oxygenator resistance, and oxygen transfer efficiency were monitored. Oxygenator blood volume decreased with increasing runtime (r = -0.462; p <0.001). There was a statistically significant, fair negative correlation between oxygenator blood volume and oxygenator resistance (r = -0.476; p<0.001) in all oxygenators, which became stronger analyzing only exchanged oxygenators (r = -0.680; p<0.001) and oxygenators with an oxygenator blood volume <187 mL (r = 0.831; p<0.001). No relevant correlation between oxygenator blood volume and O2 transfer was found. Oxygenator blood volume declined over time and was clearly associated with an increasing oxygenator resistance during prolonged extracorporeal life support, though O2 transfer was less affected.
Topics: Adult; Blood Volume; Carbon Dioxide; Extracorporeal Membrane Oxygenation; Female; Humans; Male; Middle Aged; Monitoring, Physiologic; Oxygen; Oxygenators; Regional Blood Flow
PubMed: 35108345
DOI: 10.1371/journal.pone.0263360 -
Saudi Journal of Biological Sciences Jun 2022In this study, the blood volume and oxygen saturation of tumors were measured after photoacoustic imaging (PAI) under conditions of pre-photodynamic therapy (PDT),...
In this study, the blood volume and oxygen saturation of tumors were measured after photoacoustic imaging (PAI) under conditions of pre-photodynamic therapy (PDT), post-PDT, and 4 hrs, and 24 hrs post-PDT. PDTs with aminolevulinic acid (ALA) and low and high doses of benzoporphyrin derivative (BPD) were conducted to observe oxygen saturation changes, and the rapid oxygen consumption in the blood detected due to the action of BPD at the vascular level resulted in the recovery of PDT completion. Likewise, blood volume changes followed by ALA-PDT and BPD-PDT at low and high doses depicted a fast expansion of the blood volume after treatment. The tumor subjected to a high dose of ALA-PDT showed a partial alteration of Hb-pO in the first 24 hrs, as did the tumors treated with two ALA- and BPD-mediated PDTs. The Hb-pO started reducing immediately post-PDT and was less than 30% after 4 hrs until 24 hrs post-PDT. Reduced vascular demand was possibly due to tumor necrosis, as shown by the permanent damage in the cancer cells' bioluminescence signal. The ALA-mediated PDT-subjected tumor showed a 50% drop in BV at 24 hrs post-PDT, which is suggestive of vascular pruning. The studied data of blood volume against BLI showed the blood volume and oxygenation variations validating the cells' metabolic activity, including cell death.
PubMed: 35574285
DOI: 10.1016/j.sjbs.2022.103304 -
BMC Anesthesiology Aug 2020Perioperative fluid management - including the type, dose, and timing of administration -directly affects patient outcome after major surgery. The objective of fluid... (Review)
Review
BACKGROUND
Perioperative fluid management - including the type, dose, and timing of administration -directly affects patient outcome after major surgery. The objective of fluid administration is to optimize intravascular fluid status to maintain adequate tissue perfusion. There is continuing controversy around the perioperative use of crystalloid versus colloid fluids. Unfortunately, the importance of fluid volume, which significantly influences the benefit-to-risk ratio of each chosen solution, has often been overlooked in this debate.
MAIN TEXT
The volume of fluid administered during the perioperative period can influence the incidence and severity of postoperative complications. Regrettably, there is still huge variability in fluid administration practices, both intra-and inter-individual, among clinicians. Goal-directed fluid therapy (GDFT), aimed at optimizing flow-related variables, has been demonstrated to have some clinical benefit and has been recommended by multiple professional societies. However, this approach has failed to achieve widespread adoption. A closed-loop fluid administration system designed to assist anesthesia providers in consistently applying GDFT strategies has recently been developed and tested. Such an approach may change the crystalloid versus colloid debate. Because colloid solutions have a more profound effect on intravascular volume and longer plasma persistence, their use in this more "controlled" context could be associated with a lower fluid balance, and potentially improved patient outcome. Additionally, most studies that have assessed the impact of a GDFT strategy on the outcome of high-risk surgical patients have used hydroxyethyl starch (HES) solutions in their protocols. Some of these studies have demonstrated beneficial effects, while none of them has reported severe complications.
CONCLUSIONS
The type and volume of fluid used for perioperative management need to be individualized according to the patient's hemodynamic status and clinical condition. The amount of fluid given should be guided by well-defined physiologic targets. Compliance with a predefined hemodynamic protocol may be optimized by using a computerized system. The type of fluid should also be individualized, as should any drug therapy, with careful consideration of timing and dose. It is our perspective that HES solutions remain a valid option for fluid therapy in the perioperative context because of their effects on blood volume and their reasonable benefit/risk profile.
Topics: Blood Volume; Fluid Therapy; Hemodynamics; Humans; Hydroxyethyl Starch Derivatives; Patient Care Planning; Perioperative Care; Plasma Substitutes
PubMed: 32819296
DOI: 10.1186/s12871-020-01128-1 -
Korean Journal of Anesthesiology Apr 2020Over 300 million surgical procedures are performed every year worldwide. Anesthesiologists play an important role in the perioperative process by assessing the overall... (Review)
Review
Over 300 million surgical procedures are performed every year worldwide. Anesthesiologists play an important role in the perioperative process by assessing the overall risk of surgery and aim to reduce the risk of complications. Perioperative hemodynamic and volume management can help to improve outcomes in perioperative patients. There has been ongoing discussion about goal-directed therapy. However, there is a consensus that fluid overload and severe fluid depletion in the perioperative period are harmful and can lead to adverse outcomes. This article provides an overview of how to evaluate the fluid responsiveness of patients, details which parameters could be used, and what limitations should be noted.
Topics: Blood Volume; Cardiac Output; Crystalloid Solutions; Fluid Therapy; Hemodynamics; Humans; Monitoring, Intraoperative; Perioperative Care
PubMed: 32106641
DOI: 10.4097/kja.20022