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JACC. Heart Failure Jun 2014
Topics: Blood Volume; Female; Heart Failure; Humans; Male
PubMed: 24952699
DOI: 10.1016/j.jchf.2014.02.006 -
Journal of Applied Physiology... Sep 2017In this Cores of Reproducibility in Physiology (CORP) article, we present the theory and practical aspects of the carbon monoxide (CO) rebreathing method for the... (Review)
Review
In this Cores of Reproducibility in Physiology (CORP) article, we present the theory and practical aspects of the carbon monoxide (CO) rebreathing method for the determination of total hemoglobin mass in humans. With CO rebreathing, a small quantity of CO is diluted in O and rebreathed for a specified time period, during which most of the CO is absorbed and bound to circulating hemoglobin. The dilution principle then allows calculation of the total number of circulating hemoglobin molecules based on the number of absorbed CO molecules and the resulting changes in the fraction of carboxyhemoglobin in blood. Total hemoglobin mass is derived by multiplication with the molar weight of hemoglobin. CO rebreathing has been used for >100 yr and has undergone steady improvement so that today excellent values in terms of accuracy and precision can be achieved if the methodological precautions are carefully followed.
Topics: Blood Volume; Blood Volume Determination; Carbon Monoxide; Carboxyhemoglobin; Hemoglobins; Humans; Reproducibility of Results
PubMed: 28663373
DOI: 10.1152/japplphysiol.00185.2017 -
Cytometry. Part a : the Journal of the... Dec 2019
Topics: Blood Vessels; Blood Volume; Flow Cytometry; Humans; Theranostic Nanomedicine
PubMed: 31670875
DOI: 10.1002/cyto.a.23916 -
American Journal of Physiology. Heart... Sep 2016According to Guyton's model of circulation, mean systemic filling pressure (MSFP), right atrial pressure (RAP), and resistance to venous return (RVR) determine venous...
According to Guyton's model of circulation, mean systemic filling pressure (MSFP), right atrial pressure (RAP), and resistance to venous return (RVR) determine venous return. MSFP has been estimated from inspiratory hold-induced changes in RAP and blood flow. We studied the effect of positive end-expiratory pressure (PEEP) and blood volume on venous return and MSFP in pigs. MSFP was measured by balloon occlusion of the right atrium (MSFPRAO), and the MSFP obtained via extrapolation of pressure-flow relationships with airway occlusion (MSFPinsp_hold) was extrapolated from RAP/pulmonary artery flow (QPA) relationships during inspiratory holds at PEEP 5 and 10 cmH2O, after bleeding, and in hypervolemia. MSFPRAO increased with PEEP [PEEP 5, 12.9 (SD 2.5) mmHg; PEEP 10, 14.0 (SD 2.6) mmHg, P = 0.002] without change in QPA [2.75 (SD 0.43) vs. 2.56 (SD 0.45) l/min, P = 0.094]. MSFPRAO decreased after bleeding and increased in hypervolemia [10.8 (SD 2.2) and 16.4 (SD 3.0) mmHg, respectively, P < 0.001], with parallel changes in QPA Neither PEEP nor volume state altered RVR (P = 0.489). MSFPinsp_hold overestimated MSFPRAO [16.5 (SD 5.8) vs. 13.6 (SD 3.2) mmHg, P = 0.001; mean difference 3.0 (SD 5.1) mmHg]. Inspiratory holds shifted the RAP/QPA relationship rightward in euvolemia because inferior vena cava flow (QIVC) recovered early after an inspiratory hold nadir. The QIVC nadir was lowest after bleeding [36% (SD 24%) of preinspiratory hold at 15 cmH2O inspiratory pressure], and the QIVC recovery was most complete at the lowest inspiratory pressures independent of volume state [range from 80% (SD 7%) after bleeding to 103% (SD 8%) at PEEP 10 cmH2O of QIVC before inspiratory hold]. The QIVC recovery thus defends venous return, possibly via hepatosplanchnic vascular waterfall.
Topics: Animals; Atrial Function, Right; Blood Pressure; Blood Volume; Breath Holding; Cardiac Output; Heart Atria; Hypovolemia; Male; Positive-Pressure Respiration; Pressure; Sus scrofa; Swine; Vena Cava, Inferior
PubMed: 27422991
DOI: 10.1152/ajpheart.00931.2015 -
ESC Heart Failure Apr 2021In patients with chronic heart failure (CHF), volume overload is usually described as an expansion of plasma volume (PV). Additional red cell volume (RCV) expansion also...
BACKGROUND
In patients with chronic heart failure (CHF), volume overload is usually described as an expansion of plasma volume (PV). Additional red cell volume (RCV) expansion also occurs in a relevant fraction of compensated CHF patients. So far, little is known about the stability of these vascular volumes and possible volume excess in compensated CHF patients over time.
METHODS AND RESULTS
This study aims at quantification of blood volume and its components, RCV and PV (raw values and adjusted for sex and anthropometric characteristics, expressed as per cent of the expected normal value), using an abbreviated carbon monoxide (CO) rebreathing method (aCORM) in 14 patients (two women) with systolic CHF at baseline and at a follow-up visit after approximately 6 months. While a vast heterogeneity was observed concerning RCV (82% to 134% of normalized alues) and PV (72% to 131% of normalized values), the vascular volumes showed a mean change of 1.2% and -1.3% after a mean follow-up of 183 days.
CONCLUSIONS
The vascular volumes including individual volume excess appear to be stable in compensated CHF patients. The reason for this individual volume response concerning both RCV and PV in CHF remains unclear and deserves further clarification.
Topics: Blood Volume; Cell Size; Chronic Disease; Female; Heart Failure; Humans; Plasma Volume
PubMed: 33403801
DOI: 10.1002/ehf2.13179 -
Bulletin of the World Health... Jan 2011To determine paediatric blood sample volume limits that are consistent with physiological "minimal risk." (Review)
Review
OBJECTIVE
To determine paediatric blood sample volume limits that are consistent with physiological "minimal risk."
METHODS
A literature review was performed to search for evidence concerning the adverse effects of blood sampling in children and for guidelines on sampling volume in paediatric research. The search included Medline, EMBASE, other web-based and non-web-based sources and the bibliographies of the sources identified. Experts were also consulted.
FINDINGS
Five studies and nine guidelines were identified. Existing guidelines specify paediatric blood sample volume limits ranging from 1% to 5% of total blood volume (TBV) over 24 hours and up to 10% of TBV over 8 weeks. The evidence available is limited and includes findings from non-randomized studies showing a minimal risk with one-off sampling of up to 5% of TBV.
CONCLUSION
The evidence available is consistent with the conclusion that all identified guidelines are within the limits of "minimal risk." However, more and better evidence is required to draw firmer conclusions. Researchers and institutional review boards need to take into account the total sampling volume needed for both clinical care and research rather than for each alone. The child's general state of health should be considered and extra caution should be observed particularly with children whose illness can deplete blood volume or haemoglobin or hinder their replenishment. Local policies must also address the appropriateness and local acceptability of collection procedures and of the blood volumes drawn.
Topics: Biomedical Research; Blood Specimen Collection; Blood Transfusion; Blood Volume; Child; Hemoglobins; Humans; Practice Guidelines as Topic
PubMed: 21346890
DOI: 10.2471/BLT.10.080010 -
Journal of Clinical Laboratory Analysis May 2023Determination of blood volume (BV) using the dual-isotope (e.g., Tc-labeled red blood cells [ Tc-RBC] and I-labeled human serum albumin [ I-HSA]) injection method is...
INTRODUCTION
Determination of blood volume (BV) using the dual-isotope (e.g., Tc-labeled red blood cells [ Tc-RBC] and I-labeled human serum albumin [ I-HSA]) injection method is limited in medicine due to the long isotope half-life. However, BV has been determined in laboratory settings for 100 years using the carbon monoxide (CO)-rebreathing-based procedure, which allows frequent BV measurements.
METHODS
We investigated the reliability and accuracy of a semi-automated CO-rebreathing device by comparing it against the dual-isotope methodology and its ability to detect a known blood removal. In study A, BV was determined three times in ~2 h; twice using the device with rebreathing protocols lasting 2 (CO ) and 10 min (CO ) and once with the dual-isotope technique. In study B, the accuracy of the device was assessed by its ability to detect a 2% removal of BV.
RESULTS
A good correlation was observed between both the CO-rebreathing protocols (r = 0.89-0.98; p < 0.001) and the dual-isotope approach (r = 0.89-0.95; p < 0.001). In absolute terms BV was 425 ± 263 mL and 491 ± 388 mL lower (p < 0.001) when quantified with the dual-isotope compared to the CO-rebreathing protocols. When reducing BV by 132 ± 25 mL (2%), the device quantified a lower (p < 0.001) BV of 150 ± 45 mL.
CONCLUSION
This study emphasizes that the semi-automated device accurately determines small changes (i.e., 2%) in BV and that a high correlation with the dual-isotope methodology exists. The findings are clinically relevant owing to the method's simple and fast nature (the absence of radioactive tracers and reduced time requirements, i.e., ~15 min vs. ~180 min) and the possibility for repeated measurements within a single day.
Topics: Humans; Reproducibility of Results; Blood Volume
PubMed: 37332175
DOI: 10.1002/jcla.24928 -
British Journal of Anaesthesia Feb 2000Clinical studies to assess the benefits of blood transfusion or haemodilution in critical illness should take account of measured CBV before, during and after... (Review)
Review
Clinical studies to assess the benefits of blood transfusion or haemodilution in critical illness should take account of measured CBV before, during and after intervention. As mentioned above, surrogate measures of CBV are inadequate and studies based on these must be considered incomplete, because they cannot distinguish between effects of changes in haemoglobin concentration and changes in blood volume. The choice of a suitable technique for measuring CBV depends on the facilities available locally. In general, methods based on labelled red cells are more reliable but are technically demanding and time consuming. Those based on albumin are likely to yield false high values and this is particularly true in all patients with impaired capillary integrity. The most promising plasma marker is hydroxyethyl starch which may be particularly useful when the polysaccharide is labelled with a fluorescent dye. Attaching fluorescein to hydroxyethyl starch is not difficult and, should demand be sufficient, it may well become available from manufacturers who are already capable of providing other fluorescent polysaccharides. The clinical benefits of such a development would include more rational schedules of i.v. fluid and blood transfusion management in surgical and intensive care patients.
Topics: Blood Volume; Blood Volume Determination; Critical Care; Hematocrit; Humans; Plasma Volume
PubMed: 10743457
DOI: 10.1093/oxfordjournals.bja.a013407 -
The American Journal of Clinical... Mar 2013Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance. Unfortunately, dehydration can be difficult... (Review)
Review
Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance. Unfortunately, dehydration can be difficult to assess, and there is no single, universal gold standard for decision making. In this article, we review the physiologic basis for understanding quantitative dehydration assessment. We highlight how phenomenologic interpretations of dehydration depend critically on the type (dehydration compared with volume depletion) and magnitude (moderate compared with severe) of dehydration, which in turn influence the osmotic (plasma osmolality) and blood volume-dependent compensatory thresholds for antidiuretic and thirst responses. In particular, we review new findings regarding the biological variation in osmotic responses to dehydration and discuss how this variation can help provide a quantitative and clinically relevant link between the physiology and phenomenology of dehydration. Practical measures with empirical thresholds are provided as a starting point for improving the practice of dehydration assessment.
Topics: Blood Volume; Body Water; Dehydration; Humans; Neurophysins; Osmolar Concentration; Protein Precursors; Thirst; Vasopressins; Water-Electrolyte Balance
PubMed: 23343973
DOI: 10.3945/ajcn.112.044172 -
Minerva Anestesiologica Jun 2005The transpulmonary thermodilution indicator (TPID) technique has been recently introduced and diffuse in clinical practice. This "less-invasive" device measures... (Review)
Review
The transpulmonary thermodilution indicator (TPID) technique has been recently introduced and diffuse in clinical practice. This "less-invasive" device measures intermittent cardiac output and, based on pulse contour method, continuous cardiac output, that agree with cardiac output obtained with pulmonary artery catheter in different clinical setting. Moreover it allowed stroke volume variation and pulse pressure variation experimental and clinically validate fluid responsiveness index in controlled mechanically ventilated patients. The TPID technique allowed an estimations of preload index such as intrathoracic blood volume and "lung edema" index as extra vascular lung water. We reviewed the principle of clinical application based on the current literature now available from this device. Cardiac output monitoring based on TPID technique is safe and accurate, as well as fluid responsiveness indicator (SVV and PPV). Intrathoracic blood volume seems to be a good preload index but the results reported in literature are not homogeneous in all its applications. Extra vascular lung water index is a very interesting parameter particularly in critically ill setting but its clinical application is not yet widely documented.
Topics: Blood Volume; Cardiac Output; Extravascular Lung Water; Humans; Monitoring, Physiologic; Thermodilution
PubMed: 15886592
DOI: No ID Found