Hematocrit Measurements Research Articles

Effect of the ethanolic extract of red roselle calyx (Hibiscus sabdariffa L.) on hematocrit, platelets, and erythrocytes in healthy volunteers

Roselle calyx (Hibiscus sabdariffa L) is widely used as an antioxidant, antihepatotoxic, diuretic, anti-cholesterol, and immunostimulant. Roselle contains anthocyanin and quercetin that have antioxidant activity. This study aimed to determine the effects of the ethanolic extract of roselle calyx on hematocrit, platelets, and erythrocytes in healthy volunteers during the 30-day administration and 15 days after it ceased. This study employed pre- and post-treatment design on 21 healthy volunteers, comprising 11 males and 10 females who fulfilled the inclusion criteria and filled out the informed consent form willingly. Volunteers were provided with roselle capsules for 30 days with a dosage of 500 mg a day taken 10-15 minutes after dinner. The hematologic examination was performed on Day 0, 31, and 45, including the measurement of hematocrit, platelet, and erythrocyte levels using a hematology analyzer. The obtained data were analyzed in SPSS with paired t-test and Wilcoxon test. The results showed that the hematocrit, platelets, and erythrocytes of all male and female volunteers on Day 0, 31, and 45 were within the normal range. The comparison analysis affirmed that there was no significant difference between these three parameters from Day 0 to 31, Day 31 to 45, and Day 0 to 45 (p>0.05). As a conclusion, the administration of the ethanolic extract of roselle calyx with a dosage of one 500mg capsule per day for 30 days did not affect the hematocrit, platelets, and erythrocytes in healthy volunteers. There was also no delayed effect on these three hematological parameters 15 days after the administration stopped.

Heart Failure Outcomes With Volume-Guided Management

ObjectivesThis study performed a retrospective outcome analyses of a large cohort of mixed ejection fraction patients admitted for acute heart failure (HF), whose inpatient care was guided by individual quantitative blood volume analysis (BVA) results. BackgroundDecongestion strategies in patients hospitalized for HF are based on clinical assessment of volume and have not integrated a quantitative intravascular volume metric. MethodsPropensity score control matching analysis was performed in 245 consecutive HF admissions to a community hospital (September 2007 to April 2014; 78 ± 10 years of age; 50% with HF with reduced ejection fraction [HFrEF]; and 30% with Stage 4 chronic kidney disease). Total blood volume (TBV), red blood cell volume (RBCV), and plasma volume (PV) were measured at admission by using iodine-131-labeled albumin indicator-dilution technique. Decongestion strategy targeted a TBV threshold of 6% to 8% above patient-specific normative values. Anemia was treated based on cause. Hematocrit (Hct) measurements were monitored to assess effectiveness of interventions. Control subjects derived from Centers for Medicare and Medicaid Services data were matched 10:1 for demographics, comorbidity, and year of treatment. ResultsAlthough 66% of subjects had PV expansion, only 37% were hypervolemic (TBV >10% excess). True anemia (RBCV ≥10% deficit) was present in 62% of subjects. Treatment of true anemia without hypervolemia resulted in a rise in peripheral Hct of 2.7 ± 2.9% (p < 0.001), and diuretic treatment of hypervolemia in cases without anemia caused a 4.5 ± 3.9% (p < 0.001) increase in peripheral Hct at 11.3 ± 7.5 days after admission. Subjects had lower 30-day rates of readmission (12.2% vs. 27.7%, respectively; p < 0.001), of 30-day mortality (2.0% vs. 11.1%, respectively; p < 0.001), and of 365-day mortality (4.9% vs. 35.5%, respectively; p < 0.001) but longer lengths of stay (7.3 vs. 5.6 days, respectively; p < 0.001) than control subjects. ConclusionsRetrospective outcomes using volume-guided HF therapy versus propensity-matched controls support the benefit of BVA in guiding volume management and reducing death and rehospitalization due to HF.

Biochemical Determinants of Changes in Plasma Volume After Decongestion Therapy for Worsening Heart Failure

Optimal vascular volume is required to avoid organ dysfunction during decongestive therapy for worsening heart failure (HF). This study investigated the relation between changes in serum substance(s) and the vascular volume after diuresis in HF patients. Data from 47 patients with HF undergoing conventional diuretic therapy were analyzed. Blood tests included measurements of hemoglobin, hematocrit, and serum albumin/solutes. The relative changes in the plasma volume (%PV) from worsening HF to recovery were determined with the use of the Strauss formula. When divided into 2 groups based on the median %PV, the group with preserved volume (%PV ≥ -10%, range -10% to 21%; n = 23) exhibited a smaller decrease in body weight (-2.50 ± 1.98 vs -4.29 ± 2.60 kg; P = .012) and serum sodium (Na) (-1.57 ± 3.29 vs -4.13 ± 4.96 mEq/L; P = .04) and chloride (Cl) (-2.0 ± 4.06 vs -6.79 ± 5.21 mEq/L; P = .001) concentrations and a smaller increase in albumin (0.20 ± 0.28 vs 0.41 ± 0.24g/dL; P = .009) compared with the group with nonpreserved volume (%PV < -11%, range -33% to -11%; n = 24) after decongestive therapy. Changes in %PV were positively correlated with changes in body weight (r = 0.406; P = .0047) and serum Na (r = 0.433; P = .0024) and Cl (r = 0.408; P = .0044) concentrations and negatively correlated with changes in albumin (r = -0.492; P = .0004), blood urea nitrogen (r = -0.306; P = .037), and creatinine (r = -0.306; P = .036). Multivariate logistic regression analysis demonstrated an independent association between preserved %PV and an increased or preserved serum Cl concentration after decongestive therapy (odds ratio 8.71, 95% confidence interval 1.20-63.0; P = .032). Positive and independent association exists between change in the vascular volume and the serum Cl concentration under decongestive HF therapy.

Fluctuant Mass on an Infant’s Scalp

A term infant has the following scalp examination [click on the video]. Of the options shown in Fig 1A (A, B, C, or D) of the top of an infant’s head, what is the most likely location of the involved area in this infant? Video. Click here to view the video. Figure 1A. Locations for potential collections that are exterior and interior to an infant’s skull. The video of this newborn shows a moderate-to-large fluctuant mass gathered in the dependent portion of the neonate’s scalp. Upon gentle tapping of the boggy collection, there is a clearly visible fluid wave. This finding is most consistent with a subgaleal hemorrhage. Subgaleal hemorrhage is a serious, potentially fatal event in a newborn. It is caused by the rupture of large, bridging, emissary veins that connect the scalp veins to the intracranial dural sinuses. When these veins rupture, blood accumulates between the periosteum and the galeal aponeurotica, a large potential space composed of loose connective tissue. This space extends without restriction across the cranium and can hold as much as 260 mL of blood. (1) (Note: The average total blood volume in a term infant is 80–90 mL/kg.) A hemorrhage of …

Hematocrit Measurement with R2* and Quantitative Susceptibility Mapping in Postmortem Brain.

Noninvasive venous oxygenation quantification with MR imaging will improve the neurophysiologic investigation and the understanding of the pathophysiology in neurologic diseases. Available MR imaging methods are limited by sensitivity to flow and often require assumptions of the hematocrit level. In situ postmortem imaging enables evaluation of methods in a fully deoxygenated environment without flow artifacts, allowing direct calculation of hematocrit. This study compares 2 venous oxygenation quantification methods in in situ postmortem subjects. Transverse relaxation (R2*) mapping and quantitative susceptibility mapping were performed on a whole-body 4.7T MR imaging system. Intravenous measurements in major draining intracranial veins were compared between the 2 methods in 3 postmortem subjects. The quantitative susceptibility mapping technique was also applied in 10 healthy control subjects and compared with reference venous oxygenation values. In 2 early postmortem subjects, R2* mapping and quantitative susceptibility mapping measurements within intracranial veins had a significant and strong correlation (R2 = 0.805, P = .004 and R2 = 0.836, P = .02). Higher R2* and susceptibility values were consistently demonstrated within gravitationally dependent venous segments during the early postmortem period. Hematocrit ranged from 0.102 to 0.580 in postmortem subjects, with R2* and susceptibility as large as 291 seconds-1 and 1.75 ppm, respectively. Measurements of R2* and quantitative susceptibility mapping within large intracranial draining veins have a high correlation in early postmortem subjects. This study supports the use of quantitative susceptibility mapping for evaluation of in vivo venous oxygenation and postmortem hematocrit concentrations.

Cattle tick infestation in Brangus cattle raised with Nellore in central Brazil

The present study evaluated the behavior of Rhipicephalus microplus naturally infesting Brangus cattle raised with Nellore animals in the municipality of Água Clara, state of Mato Grosso do Sul, Central Brazil. For the field experiment composed of a group with 15 Brangus animals and 15 Nellore animals and a control group with 30 Brangus cattle, all at the post-weaning stage. The 2 groups were kept for 6 months in 2 adjacent paddocks, naturally infested with ticks, at a stocking rate of approximately 0.6 of an animal unit per hectare (AU/ha). Every 18 days, the animals were weighed, and ticks on both sides of each bovine were counted. Every 36 days, blood was collected for hematocrit measurement and molecular diagnosis of the 3 pathogens that cause tick fever. The Brangus animals had 6.8 times more ticks than the Nellore cattle. No significant difference was observed in the weight gain of the Brangus and Nellore animals, and no correlation between the number of ticks and weight was observed in either group. During the 6 months of the study, all animals presented normal hematocrit, were positive for Babesia bigemina and Anaplasma marginale, and were negative for Babesia bovis. Animals in Group 1 produced 27% fewer ticks than the animals in Group 2. The production rate of engorged female ticks in Nellore and Brangus cattle was 0.83% and 2.01%, respectively. Considering the infestation pattern required to produce 10 engorged females/day/animal, the Nellore and Brangus animals required 1,204 and 497 larvae/day, respectively. Our estimates showed that Brangus cattle need only 11.3% of the larvae in the pastures with Nellore cattle to maintain the infestation level observed in the present study. Brangus animals raised with Nellore cattle do not have a lower parasitic load and continue to suffer from tick infestation. Finally, Nellore cattle raised with Brangus cattle do not act as a cleaner because this grouping does not contribute to a reduced infestation in the Brangus animals.

Measurement of Blood Loss in Cardiac Surgery: Still Too Much

Cardiac surgery is associated with a significant decrease in hematocrit. It is unclear whether that occurs from hemodilution, loss of red cells, or both. Hematocrit is a major determinant of transfusion decisions although transfusion is associated with increased morbidity and mortality. Physicians must determine whether this anemia is the result of hemodilution or redblood cell loss as the former would be treated withpacked red blood cell transfusions and the latter bydiuresis. We hypothesize that the decrease in hematocrit observed in cardiac surgery is due to hemodilution. Blood volume (BV), plasma volume (PV), and red blood cell volume (RBCV) were measured in 54 patients undergoing coronary artery bypass graft surgery, valve surgery, or coronary artery bypass graft/valve surgery. Measurements were made preoperatively, immediately postoperatively, and 2 hours after surgery utilizing a dilution tracer method and hematocrit measurements. Preoperative average BV was 6,094 mL (SD 1,904 mL), RBCV was 2,024 mL (SD 720 mL), and PV was 4,070 mL (SD 1,339 mL). Postoperative average BV was 4,834 mL (SD 1,432 mL), RBCV 1,226 mL (SD 527 mL), and PV 3,607 mL (SD 993 mL). Blood volume decreased 18% (p < 0.0001), RBCV decreased 38% (p < 0.001), and PV decreased 8% (p < 0.012). There were no significant changes between postoperative values and those 2 hours later in the cardiac surgery intensive care unit. Decreases in hematocrit observed in cardiac surgery patients are due to significant red blood cell losses and not to hemodilution. Red blood cell losses averaged 38%. Plasma volume also decreased.

A multivariate approach to the diagnosis of gastrointestinal infection in ewes

Diagnosing the effects of helminth infections is an efficient way to manage the problem in ruminant production systems. Selection of animals in a flock that are infected with Haemonchus has traditionally involved differential packed cell volume measurements (PCV), and in recent years, the FAMACHA© system has been used. However, few small analytical changes have been made. The objective of this study was to examine the influence of different diagnoses linked to packed cell volume (PCV) and FAMACHA© system scores in native ewes, using a multivariate approach. Ewes were classified into three categories according to their score in the FAMACHA© system (FS) and their packed cell volumes (PCV) as follows: Group AG (FS between 1 and 2 and PCV ≥ 30%); Group BG (FS score of 3 and PCV between 21 and 29%); Group CG (FS between 4 and 5 and PCV ≤ 20%). The animals were evaluated using performance characteristics, parasitological examinations, blood values and serum biochemistry. The data show that the use of a multivariate approach for different diagnoses using the FAMACHA© system and PCV measurements gives similar results, although they have particular pathophysiological indicator patterns.

Extracellular volume fraction measurements derived from the longitudinal relaxation of blood-based synthetic hematocrit may lead to clinical errors in 3\xa0T cardiovascular magnetic resonance

BackgroundThe extracellular volume (ECV), derived from cardiovascular magnetic resonance (CMR) T1 mapping, is a biomarker of the extracellular space in the myocardium. The hematocrit (HCT), measured from venipuncture, is required for ECV measurement. We test the clinic values of synthetic ECV, which is derived from the longitudinal relaxation of blood–based (T1blood) synthetic hematocrit in 3 T CMR.MethodsA total of 226 subjects with CMR T1 mapping and HCT measurement taken on the same day as the CMR were retrospectively enrolled and randomly split into derivation (n = 121) and validation (n = 105) groups, comprising healthy subjects (n = 45), type 2 diabetes mellitus (T2DM) patients (n = 60), hypertrophic cardiomyopathy (HCM) patients (n = 93), and 28 other patients. Correlation of T1blood with the measured HCT (HCTm) was established in the derivation group and used in both the derivation and the validation groups. The relationships between the ECV values derived from both the synthetic HCT (HCTsyn) and HCTm were explored. In addition, the differences in the ECV values among the HC, T2DMs, and HCMs were compared.ResultsRegression between the HCTm and 1/T1blood was linear (R2 = 0.19, p < 0.001), and the regression equation was: HCTsyn = [561.6*(1/T1blood)] + 0.098 in the derivation group. The measured ECV (ECVm) was strongly correlated with the synthetic ECV (ECVsyn) (R2 = 0.87, p < 0.001) and mildly correlated with the difference between the ECVsyn and ECVm (R2 = 0.10, p < 0.001) in the derivation group. Also in this group, the ECVm was larger in T2DMs than that in healthy cohort (29.1 ± 3.1% vs. 26.4 ± 2.4%, p = 0.002), whereas, the ECVsyn did not differ between T2DMs and healthy cohort (28.3 ± 2.9% vs. 26.9 ± 2.2%, p = 0.064). Compared with the healthy cohort, the HCMs were associated with higher ECVsyn and ECVm of the mid-ventricle in both the derivation and the validation groups. Using our center’s normal cut-off of 31.8%, the use of ECVsyn would lead to a 6–25% incorrect categorization of patients in the derivation and validation groups.ConclusionsECVsyn derived from HCTsyn may lead to clinical errors in 3 T CMR, especially for patients who have only a subtle elevation in ECV.

High-intensity interval training improves acute plasma volume responses to exercise that is age dependent.

Plasma volume (PV) is affected by several factors including age, physical training and, acutely, by exercise intensity. The purpose of this study was to investigate the effects of 6 weeks of high‐intensity interval training (HIT) on PV and blood pressure (BP) changes among sedentary individuals. Thirty subjects aged between 18 and 71 years [body mass index=30.1(1.2) kg/m2] completed a 6‐weeks HIT program. Anthropometric and fitness variables were obtained at pre‐ and post‐ HIT. PV variations during warm‐up and after supramaximal cycling test (SCT) were calculated using two methods based on Hematocrit (Ht) and Hemoglobin (Hb) measures. After both the warm‐up and SCT, PV decreased significantly among participants at pre‐ and at post‐HIT (P < 0.01). However, PV decreases were significantly greater at pre‐HIT compared with post‐HIT during warm‐up and after SCT (P < 0.01, respectively). In addition, at pre‐HIT, a positive relationship was found between age and both PV variations at warm‐up and after SCT (r 2 = 0.55 and r 2 = 0.46; P < 0.01 respectively). However, no relationship was found during the post‐HIT period. After SCT and after both visits, only body weight predicted 22% of PV variations. In the current study, a significant relationship was found between systolic and diastolic BP improvements and PV variations in post‐HIT (r 2 = 0.54 and r 2=0.56, P < 0.05, respectively). Our results suggest that HIT may improve PV values and reduce the effects of age on the decrease in PV. These interventions led to improvements in systolic and diastolic BP values among participants.

Noninvasive hematocrit assessment for cardiovascular magnetic resonance extracellular volume quantification using a point-of-care device and synthetic derivation

BackgroundCalculation of cardiovascular magnetic resonance (CMR) extracellular volume (ECV) requires input of hematocrit, which may not be readily available. The purpose of this study was to evaluate the diagnostic accuracy of ECV calculated using various noninvasive measures of hematocrit compared to ECV calculated with input of laboratory hematocrit as the reference standard.MethodsOne hundred twenty three subjects (47.7 ± 14.1 years; 42% male) were prospectively recruited for CMR T1 mapping between August 2016 and April 2017. Laboratory hematocrit was assessed by venipuncture. Noninvasive hematocrit was assessed with a point-of-care (POC) device (Pronto-7® Pulse CO-Oximeter®, Masimo Personal Health, Irvine, California, USA) and by synthetic derivation based on the relationship with blood pool T1 values. Left ventricular ECV was calculated with input of laboratory hematocrit (Lab-ECV), POC hematocrit (POC-ECV), and synthetic hematocrit (synthetic-ECV), respectively. Statistical analysis included Wilcoxon signed-rank test, Bland-Altman analysis, receiver-operating curve analysis and intra-class correlation (ICC).ResultsThere was no significant difference between Lab-ECV and POC-ECV (27.1 ± 4.7% vs. 27.3 ± 4.8%, p = 0.106), with minimal bias and modest precision (bias − 0.18%, 95%CI [− 2.85, 2.49]). There was no significant difference between Lab-ECV and synthetic-ECV (26.7 ± 4.4% vs. 26.5 ± 4.3%, p = 0.084) in subjects imaged at 1.5 T, although bias was slightly higher and limits of agreement were wider (bias 0.23%, 95%CI [− 2.82, 3.27]). For discrimination of abnormal Lab-ECV ≥30%, POC-ECV had good diagnostic performance (sensitivity 85%, specificity 96%, accuracy 94%, and AUC 0.902) and synthetic-ECV had moderate diagnostic performance (sensitivity 71%, specificity 98%, accuracy 93%, and AUC 0.849). POC-ECV had excellent test-retest (ICC 0.994, 95%CI[0.987, 0.997]) and inter-observer agreement (ICC 0.974, 95%CI[0.929, 0.991]).ConclusionsMyocardial ECV can be accurately and reproducibly calculated with input of hematocrit measured using a noninvasive POC device, potentially overcoming an important barrier to implementation of ECV. Further evaluation of synthetic ECV is required prior to clinical implementation.

Importance of standardizing timing of hematocrit measurement when using cardiovascular magnetic resonance to calculate myocardial extracellular volume (ECV) based on pre- and post-contrast T1 mapping

BackgroundCardiovascular magnetic resonance (CMR) can be used to calculate myocardial extracellular volume fraction (ECV) by relating the longitudinal relaxation rate in blood and myocardium before and after contrast-injection to hematocrit (Hct) in blood. Hematocrit is known to vary with body posture, which could affect the calculations of ECV.The aim of this study was to test the hypothesis that there is a significant increase in calculated ECV values if the Hct is sampled after the CMR examination in supine position compared to when the patient arrives at the MR department.MethodsForty-three consecutive patients including various pathologies as well as normal findings were included in the study. Venous blood samples were drawn upon arrival to the MR department and directly after the examination with the patient remaining in supine position. A Modified Look-Locker Inversion recovery (MOLLI) protocol was used to acquire mid-ventricular short-axis images before and after contrast injection from which motion-corrected T1 maps were derived and ECV was calculated.ResultsHematocrit decreased from 44.0 ± 3.7% before to 40.6 ± 4.0% after the CMR examination (p < 0.001). This resulted in a change in calculated ECV from 24.7 ± 3.8% before to 26.2 ± 4.2% after the CMR examination (p < 0.001). All patients decreased in Hct after the CMR examination compared to before except for two patients whose Hct remained the same.ConclusionVariability in CMR-derived myocardial ECV can be reduced by standardizing the timing of Hct measurement relative to the CMR examination. Thus, a standardized acquisition of blood sample for Hct after the CMR examination, when the patient is still in supine position, would increase the precision of ECV measurements.

76 Preparation for Intrauterine Transfusion: Comparison of Hemoglobin and Hematocrit Measurements Using Spun Hematocrit, Point-of-Care Hemoglobin Analyzer, and Automated Cell Counter

76 Preparation for Intrauterine Transfusion: Comparison of Hemoglobin and Hematocrit Measurements Using Spun Hematocrit, Point-of-Care Hemoglobin Analyzer, and Automated Cell Counter

Comparison of two different coagulation algorithms on the use of allogenic blood products and coagulation factors in severely injured trauma patients: a retrospective, multicentre, observational study

BackgroundAt the University Hospital Zurich (USZ) and the Cantonal Hospital of Lucerne (LUKS) an individualized goal-directed coagulation and transfusion algorithm was introduced and implemented before 2012 (Coagulation algorithm of the USZ: USZ-Alg; of the LUKS: LUKS-Alg). Main differences between both algorithms are: 1) A target haematocrit-range of 0.21–0.24 (USZ-Alg) vs. a lower haematocrit limit only (LUKS-Alg). 2) Blind coagulation-package in selected cases (LUKS-Alg only). 3) Factor XIII substitution is considered earlier according to the USZ-Alg.The Aim of this study was to analyse the impact of two different coagulation algorithms on the administration of allogeneic blood products, coagulation factors, the frequency of point of care measurements and haemoglobin level during resuscitation in trauma patients.MethodsThis retrospective, multicentre, observational study included all adult trauma patients with an injury severity score (ISS) ≥ 16 primarily admitted to the USZ or the LUKS in the period of 2012 to 2014. Referred patients and patients with missing/incomplete records of the initial treatment at the emergency department (ED) were excluded. Two propensity score matched groups were created using a non-parsimonious logistic regression to account for potential differences in patient and trauma epidemiology.ResultsA total of 632 patients meeting the inclusion criteria were admitted to the two hospitals: 428 to the USZ and 204 to the LUKS. Two Propensity score matched groups (n = 172 per group) were created. Treatment with USZ-Alg compared with LUKS-Alg resulted in a lower number of patients receiving RBC transfusion (11.6% vs. 29.7%, OR 3.2, 95% CI 1.8–5.7, p < 0.001) and lower amount of RBC transfusion (0.5 SD 1.9 vs. 1.5 SD 3.9, p < 0.001). The different treatment algorithms resulted in lower mean haemoglobin levels in the USZ during resuscitation (8.0 SD 1.7 vs. 9.4 SD 1.8 g/dl, p < 0.001) and at admission to the ICU (8.3 SD 1.2 vs. 10.6 SD 1.9 g/dl, p < 0.001. Blood gas analyses to monitor treatment and haematocrit were made more frequently in the USZ (1.4 SD 0.8 vs. 1.0 SD 0.7 measurements per hour, p = 0.004).ConclusionA goal-directed coagulation algorithm including a target haematocrit-range including frequent and repeated haematocrit measurement may lead to less transfusion of RBC compared to only a lower haematocrit limit, when treating severely traumatized patients.

Post marketing study of hemodynamic and hematological noninvasive readings in a blood bank.

Objectives:This validation test was conducted in the Fujisan Blood Bank, Fortaleza, Brazil and evaluated the noninvasive TensorTip MTX (MTX, Cnoga Medical Ltd.) readings of hemoglobin, hematocrit, red blood cells, blood pressure, and heart rate compared to reference lab device readings. Generally, these parameters are measured from venous or capillary blood samples run on a laboratory analyzer or handheld invasive testing devices. Needle sticks are inconvenient to blood donors with relatively high exposure risks. To our vision, noninvasive determination would be of benefit to blood contributors and medical professional teams; it would be fast and painless.Methods:A total of 334 subjects were included in the Fujisan blood bank validation (65% male, 35% female). Hemoglobin, hematocrit, and red blood cells, as well as blood pressure and heart rate, were measured noninvasively using the MTX device and were compared to venous blood samples run on two laboratory hematology analyzers (Horiba ABX Micros60 and Siemens blood count analyzer), to digital sphygmomanometer (OMRON BP786) and to manual auscultation. The noninvasive measurement with the appropriate virtual arm cuff setting was performed simultaneously with the blood sample extraction of the reference devices measurement.Results:There was no statistically significant difference (p > 0.05, paired, two-tailed t-test) between the average daily hemoglobin, hematocrit, and red blood cells measurements provided by the MTX device and the laboratory hematology analyzer. In addition, there was no significant difference between the daily blood pressure and heart rate results provided by the MTX device and the digital and manual sphygmomanometers. The error calculated between the MTX and the reference device was found to be sufficiently accurate according to the relevant standards.Conclusion:The MTX accuracy of noninvasive hemoglobin, hematocrit, red blood cells, blood pressure, and heart rate measurements satisfies the industrial standards; therefore, the device enables more accurate, efficient, and effective patient care.

Safety of delayed umbilical cord clamping in preterm neonates of less than 34 weeks of gestation: a randomized controlled trial.

ObjectiveThere is concern regarding the safety of delayed cord clamping (DCC) in babies born at less than 34 weeks' gestation. Therefore, the primary objective of this study was to compare the rates of hyperbilirubinemia and polycythemia during initial 7 days in infants born at less than 34 weeks' gestation and randomized to receive DCC by 120 seconds or early cord clamping (ECC) within less than 30 seconds.MethodsOne hundred pregnant women were randomly subjected to DCC or ECC at the time of birth in a tertiary referral hospital setting. Blood samples were obtained from each newborn at 48 hours and 7 days for hematocrit measurement. Serum bilirubin levels were estimated once the infant had clinically significant jaundice or at 72 hours. For the statistical analysis, the χ2 test, student's t-test, or Wilcoxon rank sum test was used.ResultsThe hematocrit was significantly higher in the DCC group than in the ECC group (P<0.001). None of the babies had polycythemia. Mean total serum bilirubin level was 6.6 mg/dL in the DCC group and 8.7 mg/dL in the ECC group (P<0.001). There was no increased risk of hyperbilirubinemia in the DCC group.ConclusionDCC benefits preterm neonates with no significant adverse effects.

A portable optical reader and wall projector towards enumeration of bio-conjugated beads or cells.

Measurement of the height of a packed column of cells or beads, which can be direclty related to the number of cells or beads present in a chamber, is an important step in a number of diagnostic assays. For example, haematocrit measurements may rapidly identify anemia or polycthemia. Recently, user-friendly and cost-efficient Lab-on-a-Chip devices have been developed towards isolating and counting cell sub-populations for diagnostic purposes. In this work, we present a low-cost optical module for estimating the filling level of packed magnetic beads within a Lab-on-a-Chip device. The module is compatible with a previously introduced, disposable microfluidic chip for rapid determination of CD4+ cell counts. The device is a simple optical microscope module is manufactured by 3D printing. An objective lens directly interrogates the height of packed beads which are efficiently isolated on the finger-actuated chip. Optionally, an inexpensive, battery-powered Light Emitting Diode may project a shadow of the microfluidic chip at approximately 50-fold magnification onto a nearby surface. The reader is calibrated with the filling levels of known concentrations of paramagnetic beads within the finger actuated chip. Results in direct and projector mode are compared to measurements from a conventional, inverted white-light microscope. All three read-out methods indicate a maximum variation of 6.5% between methods.

Hemolysis in In-Date RBC Concentrates.

Hemolysis is one of the most prominent changes that occur during the liquid storage of RBCs in additive solution (AS), but most studies have measured hemolysis only on day 42. Prestorage leukoreduced RBCs in AS-1 and AS-3 were studied, one group on day 42 and a second group between day 0 and day 40. Each product was sampled for direct measurement of supernatant hemoglobin and hematocrit. Ninety day 42 and 218 day 7 to day 39 RBCs showed a mean ± SD supernatant hemoglobin of 75 ± 100 vs 25.5 ± 16 mg/dL respectively (P < .01). Supernatant hemoglobin correlated weakly with storage age (r = 0.2, P < .01) but more strongly with hematocrit (r = 0.4, P < .01). There are minimal differences in supernatant hemoglobin until the final days of liquid storage when some high hematocrit RBCs show excessive hemolysis.

Reliability of Point-of-Care Hematocrit Measurement During Liver Transplantation.

Although point-of-care (POC) analyzers are commonly used during liver transplantation (LT), the accuracy of hematocrit measurement using a POC analyzer has not been evaluated. In this retrospective observational study, we aimed to evaluate the accuracy of hematocrit measurement using a POC analyzer and identify potential contributors to the measurement error and their influence on mistransfusion during LT. We retrospectively collected 6461 pairs of simultaneous intraoperative hematocrit measurements using POC analyzers and laboratory devices during LTs in 901 patients. The agreement of hematocrit measurements was assessed using Bland-Altman analysis for repeated measurements, while the incidence and magnitude of hematocrit measurement error were compared among 16 different laboratory abnormality categories. A generalized estimating equation analysis was performed to identify potential contributors to falsely low-measured POC hematocrit. Additionally, we defined potential "overtransfusion" in the case when POC hematocrit was <20% and laboratory hematocrit was ≥20% and investigated its association with intraoperative transfusion. The POC hematocrit measurements were falsely lower than the laboratory hematocrit measurements in 70.3% (4541/6461) of pairs. The median (interquartile range) of hematocrit measurement error was -1.20 (-2.60 to 0.20). Bland-Altman analysis showed that 24.5% (1583/6461) of the errors were outside our a priori defined clinically acceptable limits of ±3%. The incidence of falsely low-measured hematocrit was significantly higher with the presence of concomitant hypoalbuminemia and hypoproteinemia. Hypoalbuminemia combined with hyperglycemia showed significantly larger hematocrit measurement error. Hypoalbuminemia, hypoproteinemia, and hyperglycemia were predictors of falsely low-measured hematocrit. Furthermore, the overtransfusion group showed larger amount of transfusion than the adequately transfused group, with a median difference of 2 units (95% confidence interval [0-4], P = .039), despite similar amount of blood loss. Hematocrit measured using the POC device tends to be lower than the laboratory hematocrit measured during LT. Commonly encountered laboratory abnormalities during LT include hypoalbuminemia, hypoproteinemia, and hyperglycemia, which may contribute to falsely low-measured POC hematocrit. Careful consideration of these confounders may help reduce overtransfusion that occurs due to falsely low-measured POC hematocrit.

Acoustofluidic hematocrit determination

Hematocrit (HCT) measurements of blood from patients, blood donors and athletes are routinely performed on a daily basis. These measurements are often performed in centralized hospital labs by whole blood analyzers, which leads to long time-to-result. On site measurements, based on centrifugation can be done, but these assays require manual handling, are slow and can just measure HCT in contrast to the central lab whole blood analyzers. In this work, we present a microfluidic based method to measure HCT in blood samples by acoustic separation of whole blood into discrete regions of plasma and red blood cells. Comparison of the areas of the red blood cell and plasma regions gives an accurate HCT value, with a linear correlation to the centrifugation-based reference method. A readout can be performed within 2 s of acoustic actuation providing a readout accuracy of approximately 3% points (pp) HCT. Additional accuracy can be achieved by extending the acoustic actuation to 20 s, yielding an error of less than 1 pp HCT. This acoustic tool is optimal for integration into a lab-on-a-chip device with in-line measurements of different clinical parameters.