Sheep lactate entry-rate measurements: error due to sampling jugular blood.

1977 ◽  
Vol 233 (3) ◽  
pp. E138
Author(s):  
P E Reilly ◽  
L G Chandrasena
Keyword(s):  
Venous Blood ◽  
Lactate Concentration ◽  
Specific Radioactivity ◽  
Isotope Dilution Method ◽  
Dilution Method ◽  
Entry Rate ◽  
Blood Samples ◽  
The Mean ◽  
Carotid Arterial ◽  
Arteriovenous Difference

Carotid arterial and jugular venous blood samples were taken simultaneously during primed continuous infusions of L-[U-14C]lactate in four sheep. The mean rate (n = 4) of total net formation of lactate (0.394 +/- 0.047 mg C/min per kg) calculated from the results obtained by analyzing the jugular blood samples for lactate concentration and specific radioactivity was significantly higher (0.01 greater than P greater than 0.005) than the mean rate (n = 4) calculated from the results of analysis of the arterial samples (0.302 +/- 0.036 mg C/min per kg). The error in the estimation of the rate of total net formation of lactate due to jugular sampling resulted from the negative arteriovenous difference found for lactate across the tissues of the head. These results illustrate the general need for examination of the suitability of venous sampling in experiments that make use of the continuous infusion isotope-dilution method.

Agreement between i-STAT and YSI 2300 devices to determine lactate concentrations in dogs undergoing exercise

2016 ◽  
Vol 12 (2) ◽  
pp. 75-82 ◽  
Author(s):  
C. Berkman ◽  
M.C. Pereira ◽  
K.B. Nardi ◽  
G.T. Pereira ◽  
O.A.B. Soares ◽  
...  
Keyword(s):  
Venous Blood ◽  
Lactate Concentration ◽  
Intense Exercise ◽  
Blood Samples ◽  
Handheld Device ◽  
Clinical Evaluations ◽  
Small Constant ◽  
Constant Bias ◽  
Highly Correlated ◽  
The Relationship

Little information is available comparing the i-STAT and the YSI 2300 Stat Plus devices to determine the lactate concentration [Lac] in dogs undergoing intense exercise. The reproducibility of the YSI 2300 for quantifying the [Lac] in canine blood [Lac]b and plasma [Lac]p samples has been observed. In addition, the i-STAT handheld device was used to quantify [Lac] in dogs subjected to exercise, and the results were compared with that of YSI 2300. Venous blood samples of Beagle and American Pit Bull Terrier dogs were obtained during an intense exercise training on a treadmill. [Lac]p and [Lac]b were quantified using the YSI 2300 instrument to determine the reproducibility of the results. A total of 52 specimens were compared for both plasma and whole blood. For comparing the devices (YSI 2300 vs i-STAT), 96 samples were used. Ordinary least products regression, the correlation coefficient, and Bland-Altman plots were used to assess the agreement of using the i-STAT device. The relationship between duplicate measurements of both [Lac]b and [Lac]p by YSI 2300 was strong (r=0.99). A correlation between the data obtained using the i-STAT and YSI 2300 instruments was observed for both the [Lac]p (r=0.97) and [Lac]b (r=0.88). The i-STAT exhibited a small constant bias (-0.25 mmol/l) compared to YSI 2300 ([Lac]b). There were proportional biases of 0.89 mmol/l for [Lac]p and 1.22 mmol/l for [Lac]b when using YSI 2300 vs i-STAT. We confirmed the reproducibility of the YSI 2300 for canine lactate blood/plasma samples. The results obtained by the i-STAT and YSI 2300 analyser were highly correlated, but a small constant bias was observed between them. The i-STAT device can be used in clinical evaluations, and it is also adequate for designing and monitoring fitness programmes.

Myoelectric effects of vasoactive intestinal peptide on rabbit small intestine

1983 ◽  
Vol 244 (1) ◽  
pp. G46-G51
Author(s):  
C. A. Sninsky ◽  
M. M. Wolfe ◽  
J. L. Martin ◽  
B. A. Howe ◽  
T. M. O'Dorisio ◽  
...  
Keyword(s):  
Vasoactive Intestinal Peptide ◽  
Venous Blood ◽  
Intestinal Secretion ◽  
Similar Rate ◽  
Myoelectric Activity ◽  
Rabbit Ileum ◽  
Blood Samples ◽  
Rabbit Small Intestine ◽  
The Mean ◽  
Potential Complex

Myoelectric recording techniques were used to study the motility of rabbit ileum during infusions of vasoactive intestinal peptide (VIP). VIP was infused intravenously at a rate of 300 pmol X kg-1 X h-1, and peripheral venous blood samples were obtained hourly for VIP assay. VIP was also infused intraluminally at a similar rate, and hourly portal vein blood samples were obtained for VIP assay. Alterations in motility were observed after both intravenous and intraluminal infusions of VIP. These alterations in motility consisted of the migrating action potential complex and repetitive bursts of action potentials. The VIP infusion rate used and the mean peripheral plasma VIP level of 267 +/- 29 pg/ml attained during intravenous VIP infusion were similar to those that induced intestinal secretion in other animal species. Portal venous VIP levels (93 +/- 21 pg/ml) were unchanged during the intraluminal infusion of VIP. These studies show that intravenous infusion of VIP causes alterations in motility of rabbit ileum. These alterations in motility with concomitant secretion of water and electrolytes may contribute to the diarrhea induced by VIP infusion. In addition, intraluminal infusion of VIP also induced alterations in myoelectric activity, which suggested that this peptide has a luminal effect as well as a hormonal effect.

The Influence of Orthophosphate on the Renal Handling of Inorganic Pyrophosphate in Man and Dog

1976 ◽  
Vol 51 (5) ◽  
pp. 435-443 ◽  
Author(s):  
R. G. G. Russell ◽  
Sylvia Bisaz ◽  
H. Fleisch
Keyword(s):  
Urinary Excretion ◽  
Renal Clearance ◽  
Exchange Chromatography ◽  
Urinary Stones ◽  
Isotope Dilution Method ◽  
Dilution Method ◽  
Renal Handling ◽  
Inorganic Pyrophosphate ◽  
The Mean ◽  
Hydrolysis Of

1. The urinary excretion of inorganic pyrophosphate (PP1), a known inhibitor of the growth and aggregation of crystals of calcium phosphate and calcium oxalate, increases after ingestion of orthophosphate (P1). This effect may contribute to the apparent ability of oral phosphate to reduce the formation of urinary stones in man. This paper is a study of the mechanism by which P1 increases PP1 excretion, investigated by renal clearance techniques in man and renal arterial infusion in dogs. PP1 in plasma was measured by an isotope-dilution method after ion-exchange chromatography. 2. The mean renal clearance of endogenous PP1 in ten men was 7·9 ± 1·7 (se) ml/min, and the mean ratio of PP1 clearance to creatinine clearance was 008 ±002 (se). The oral ingestion of P1 increased the urinary excretion and renal clearance of PP1 about threefold, without significantly changing its concentration in plasma. 3. In dogs, the infusion of P1 into one renal artery caused a greater increase in urinary PP1 from the infused than from the non-infused kidney, an effect that could be accentuated by simultaneous intravenous infusion of PP1. In dogs, only 1–3% of an injected or infused dose of PP1 appeared intact in the urine, regardless of whether it was infused into the systemic or renal circulation. 4. These results suggest that P1 has a direct effect on the kidney to increase the excretion of PP1. It is possible that P1 either interferes with tubular reabsorption of PP1, perhaps by competing for a common tubular transport mechanism, or that P1 diminishes the intrarenal hydrolysis of PP1.

Glucose lactate interrelations in sheep.

1978 ◽  
Vol 235 (5) ◽  
pp. E487
Author(s):  
P E Reilly ◽  
L G Chandrasena
Keyword(s):  
Plasma Glucose ◽  
Glucose Concentration ◽  
Lactate Concentration ◽  
Lactate Production ◽  
Plasma Glucose Concentration ◽  
Constant Infusion ◽  
Dilution Method ◽  
Entry Rate ◽  
Net Production ◽  
Arterial Plasma

The constant-infusion, isotope-dilution method was used to investigate the interrelationships between the glucose and lactate pools of six trained sheep deprived of food overnight. Arterial plasma lactate concentration was a linear function of the net lactate entry rate as was the net production of glucose from lactate, which suggests that the net rate of formation of glucose from lactate is dependent on the availability of lactate. Similarly the arterial plasma glucose concentration was correlated with the net entry rate of glucose as was the net production rate of lactate from glucose, suggesting that the net rate of lactate production from glucose is a function of arterial plasma glucose concentration. The demonstration of these two interrelations between glucose and lactate in normal sheep suggests that, in the absence of external factors producing hormonal or other changes that could cause perturbations of carbohydrate homeostasis, the net rates of conversion of glucose to lactate and of lactate to glucose may be largely determined by the arterial concentrations of glucose and lactate, respectively.

Validation of Oxygen Saturation Monitoring in Neonates

2007 ◽  
Vol 16 (2) ◽  
pp. 168-178 ◽  
Author(s):  
Shyang-Yun Pamela K. Shiao ◽  
Ching-Nan Ou
Keyword(s):  
Oxygen Saturation ◽  
Pulse Oximetry ◽  
Venous Blood ◽  
Arterial Oxygen ◽  
Dissociation Curve ◽  
Oxyhemoglobin Dissociation Curve ◽  
Blood Samples ◽  
Arterial Blood ◽  
The Mean ◽  
Oxyhemoglobin Dissociation

•Background Pulse oximetry is commonly used to monitor oxygenation in neonates, but cannot detect variations in hemoglobin. Venous and arterial oxygen saturations are rarely monitored. Few data are available to validate measurements of oxygen saturation in neonates (venous, arterial, or pulse oximetric). •Purpose To validate oxygen saturation displayed on clinical monitors against analyses (with correction for fetal hemoglobin) of blood samples from neonates and to present the oxyhemoglobin dissociation curve for neonates. •Method Seventy-eight neonates, 25 to 38 weeks’ gestational age, had 660 arterial and 111 venous blood samples collected for analysis. •Results The mean difference between oxygen saturation and oxyhemoglobin level was 3% (SD 1.0) in arterial blood and 3% (SD 1.1) in venous blood. The mean difference between arterial oxygen saturation displayed on the monitor and oxyhemoglobin in arterial blood samples was 2% (SD 2.0); between venous oxygen saturation displayed on the monitor and oxyhemoglobin in venous blood samples it was 3% (SD 2.1) and between oxygen saturation as determined by pulse oximetry and oxyhemoglobin in arterial blood samples it was 2.5% (SD 3.1). At a Pao2 of 50 to 75 mm Hg on the oxyhemoglobin dissociation curve, oxyhemoglobin in arterial blood samples was from 92% to 95%; oxygen saturation was from 95% to 98% in arterial blood samples, from 94% to 97% on the monitor, and from 95% to 97% according to pulse oximetry. •Conclusions The safety limits for pulse oximeters are higher and narrower in neonates (95%–97%) than in adults, and clinical guidelines for neonates may require modification.

Effect of Blood Lactate Sample Site and Test Protocol on Training Zone Prescription in Rowing

2008 ◽  
Vol 3 (3) ◽  
pp. 347-358 ◽  
Author(s):  
Stephen W. Garland ◽  
Greg Atkinson
Keyword(s):  
Power Output ◽  
Random Error ◽  
Lactate Concentration ◽  
Incremental Exercise ◽  
Systematic Bias ◽  
Test Protocol ◽  
Blood Samples ◽  
Sample Site ◽  
The Mean ◽  
Power Outputs

Purpose:To assess the effect of sample site (earlobe vs toe) and incremental exercise protocol (continuous vs discontinuous) on training zone prescription in rowing.Methods:Twenty-six rowers performed two incremental exercise tests on an ergometer: (1) a five-step discontinuous test with 4-min stages and 30-W increment, with blood samples taken from the earlobe and toe at the start of the 1-min break between steps; (2) a continuous test, with 2-min stages and 30-W increment, with blood samples taken from the right first toe at the end of each stage. Blood was analyzed for lactate concentration.Results:At a lactate concentration of 2 mmol·L−1, the mean (95% CI) power output was 8.1 (± 15.4) W greater for the continuous protocol, the random error between the methods (1.96 × SD of differences) was ± 58.8 W, and there was no evidence of any relationship between power output and error between methods. At a lactate concentration of 4 mmol·L−1, the mean (95% CI) power output was 24.2 (± 17.0) W greater for the continuous protocol, and the random error was ± 64.8 W. At 4 mmol·L−1, systematic bias between methods increased with high power outputs.Conclusions:The continuous protocol with toe sampling led to higher power outputs for a given lactate concentration compared with the discontinuous protocol with earlobe sampling. This was partly due to the choice of sample site and largely due to the choice of protocol. This bias, and also random variability, makes direct comparison of these tests inappropriate.

scholarly journals Accuracy and Precision of a Point-of-Care HbA1c Test

2019 ◽  
Vol 14 (5) ◽  
pp. 883-889
Author(s):  
William D. Arnold ◽  
Kenneth Kupfer ◽  
Randie R. Little ◽  
Meera Amar ◽  
Barry Horowitz ◽  
...  
Keyword(s):  
Whole Blood ◽  
Point Of Care ◽  
Venous Blood ◽  
Reference Laboratory ◽  
Test Results ◽  
Blood Samples ◽  
Accuracy And Precision ◽  
The Mean ◽  
Whole Blood Samples ◽  
Highly Correlated

Background: Point-of-care (POC) hemoglobin A1c (HbA1c) testing has advantages over laboratory testing, but some questions have remained regarding the accuracy and precision of these methods. The accuracy and the precision of the POC Afinion™ HbA1c Dx test were investigated. Methods: Samples spanning the assay range were collected from prospectively enrolled subjects at three clinical sites. The accuracy of the POC test using fingerstick and venous whole blood samples was estimated via correlation and bias with respect to values obtained by an NGSP secondary reference laboratory (SRL). The precision of the POC test using fingerstick samples was estimated from duplicate results by calculating the coefficient of variation (CV) and standard deviation (SD), and separated into its components using analysis of variance (ANOVA). The precision of the POC test using venous blood was evaluated from samples run in four replicates on each of three test cartridge lots, twice per day for 10 consecutive days. The SD and CV by study site and overall were calculated. Results: Across the assay range, POC test results from fingerstick and venous whole blood samples were highly correlated with results from the NGSP SRL ( r = .99). The mean bias was −0.021% HbA1c (−0.346% relative) using fingerstick samples and −0.005% HbA1c (−0.093% relative) using venous samples. Imprecision ranged from 0.62% to 1.93% CV for fingerstick samples and 1.11% to 1.69% CV for venous samples. Conclusions: The results indicate that the POC test evaluated here is accurate and precise using both fingerstick and venous whole blood.

Effects upon glucose metabolism of feeding a low-or high-roughage diet at two levels of intake to sheep

1975 ◽  
Vol 33 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Essi Evans ◽  
J. G. Buchanan-Smith
Keyword(s):  
Glucose Metabolism ◽  
Half Life ◽  
Venous Blood ◽  
Specific Radioactivity ◽  
Dietary Treatment ◽  
Pool Size ◽  
Entry Rate ◽  
Soya Bean Meal ◽  
Subsequent Withdrawal ◽  
Dietary Treatments

1. To determine the effect of diet and level of energy intake on glucose metabolism in sheep, four dietary treatments consisting of feeding a low-roughage (LR) and a high-roughage (HR) diet at each of two intake levels estimated to provide 586 and 1172 kJ (140 and 280 kcal) digestible energy (DE)/kg body-weight0·75 per d were given to each of eight yearling rams in four different time periods each of 4 weeks duration. Both diets contained 140 g crude protein/ kg using ground maize, mixed hay and soya-bean meal and were given in two meals/d. Estimated DE values of food were verified during the study and actual intakes of DE were within 9·5% of the estimated values.2. To study glucose metabolism, a single intravenous injection of [2-3H]glucose and subsequent withdrawal of nine venous blood samples within 3 h were made in each experiment. Two experiments were conducted on consecutive days for each sheep on each dietary treatment.3. Coefficients of determination (r2) for linear regressions to measure the effect of time after a single injection of [2-3H]glucose on log specific radioactivity of plasma glucose were calculated for fifty-eight experiments. In fifty-six of the experiments, r2 values exceeding 0·95 were obtained.4. Compared to the HR diet, the LR diet increased (P < 0·05) the pool size and decreased (P < 0·05) the half-life of glucose. At both intake levels, the LR diet increased (P < 0·05) the plasma concentration and the entry rate of glucose compared to the HR diet but interaction (P < 0·05) between diet and intake level was attributed to a greater difference obtained between diets at the higher compared to the lower level of food intake. Increasing the level of intake caused a greater (P < 0·05) pool size and space, and a shorter (P < 0·05) half-life of glucose.5. It was concluded that substitution of roughage by concentrate in a ruminant's diet may increase the rate of glucose entry during a short time period after eating.

scholarly journals Metabolism of Cystine by Merino Sheep Genetically Different in Wool Production IV. Rates of Entry of Cystine Into Plasma, Measured With a Single Intravenous Injection of L- [35S] Cystine, and the Subsequent Incorporation of 35S Into Wool Fibres

1976 ◽  
Vol 29 (6) ◽  
pp. 513 ◽  
Author(s):  
AJ Williams
Keyword(s):  
Intravenous Injection ◽  
Venous Blood ◽  
Specific Radioactivity ◽  
Dietary Treatment ◽  
Pool Size ◽  
Entry Rate ◽  
Merino Sheep ◽  
Fleece Weight ◽  
Dietary Treatments ◽  
Subsequent Incorporation

Ten, 2-year-old Merino ewes from a flock selectively bred for high clean fleece weight (Fleece Plus) and ten from a flock bred for low clean fleece weight (Fleece Minus) were randomly divided between two dietary treatments: 600 or 1100 g/day of pelleted lucerne hay. After 14 weeks, each ewe received an intravenous injection of L-[35Sjcystine (66�4.uCi). Venous blood samples were collected at 15 specified times until 8 h after the injections, and wool fibres were plucked until 65-75 days after the injections. Protein-free filtrates prepared from blood plasma were bulked within sample times for ewes from the same flock and dietary treatment. Equations relating the specific radioactivity of free cystine isolated from the bulked filtrates to time after injection contained three exponential terms. The entry rate and pool size of cystine estimated from these equations were greater in Fleece Minus than in Fleece Plus ewes (by 25 and 44 % respectively for entry rate and pool size). Both traits were also higher in ewes offered 1100 g lucerne/day than in those offered 600 g/day (58�7 v. 33�9 mg/h for entry rate and 19�2 v. 11� 8 mg for pool size). The concentration offree cystine in plasma was greater in ewes offered 1100 g lucerne/day (3�0 v. 2�1 mg/I; P < O� 05), and greater in Fleece Minus ewes (3�0 v. 2�1 mg/I; P < 0�05).

Accuracy of Point of Care Testing in Patients on Dual Anticoagulation During Initiation of Anticoagulation or Bridging,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3360-3360
Author(s):  
Anja B Drebes ◽  
Paul Priest ◽  
Shaila Bates ◽  
Lida Moghaddam ◽  
Edward GD Tuddenham ◽  
...  
Keyword(s):  
Point Of Care ◽  
Venous Blood ◽  
Plasma Concentrations ◽  
Internal Quality ◽  
Point Of Care Testing ◽  
Blood Samples ◽  
The Mean ◽  
Group 2 ◽  
Therapeutic Doses ◽  
Group 1

Abstract Abstract 3360 Background: Point-of-care testing (POCT) is widely used for monitoring of the international normalized ratio (INR) in patients on oral anticoagulation with a vitamin-K antagonist (VKA) and numerous clinical studies have assessed the accuracy of this method in comparison with INR results from venous blood samples analysed in the laboratory. There is however a paucity of clinical data to support the use of POCT in patients on dual anticoagulation with low molecular weight heparin (LMWH) and a VKA during initiation of anticoagulation or bridging after a surgical procedure. Aim: To test the hypothesis whether therapeutic doses of LMWH interfere with INR measurements when using a POCT system during times of dual anticoagulation with LMWH and a VKA. To further investigate whether the effect is most pronounced once LMWH has reached peak plasma levels and less evident 10 hours and more after administration of LMWH. Methods: We prospectively collected 160 consecutive venous blood samples from patients on therapeutic doses of LMWH - Tinzaparin (175 IU/kg once daily) and a VKA commonly warfarin for INR testing in our laboratory. At the same time all patients had their INR determined on capillary blood collected by finger prick using a CoaguChek XS Pro and INR test strips with the same lot number (Roche Diagnostics Ltd, UK). 60 blood samples were collected within 3–6 hours after administration of LMWH (group 1) and 100 samples were collected 10 hours or more after the last injection of LMWH (group 2). For each sample the dose and time of the last injection of LMWH was recorded along with the time of the venepuncture and the result of the capillary INR. To ensure that we had a wide variation in the plasma concentrations of LMWH we carried out anti-Xa testing on a cross-section of venous samples The dosing advice for Warfarin was based on the INR result of the venous blood sample processed in the laboratory. Results: The correlation coefficient between the POCT INR and the laboratory INR was 0.98 in group 1 and 0.97 in group 2. In the Bland Altman analysis for group 1 the mean 95% confidence interval (CI) was 0.03 (range+/− 1.96 SD: −0.26 to +0.32) and for group 2 the mean 95% CI was 0.00 (range −0.28 to +0.29). These results are comparable to results of our internal quality control between POCT INR and laboratory INR in patients on VKA alone with a mean 95% CI of −0.02 (range −0.26 to +0.29). The mean INR was 1.8 by both methods in group 1 and 1.7 by both methods in group 2 and anti-Xa levels ranged from 0 to1.19 U/mL. A variation in the result of the POCT INR and laboratory INR of 0.5 or greater is thought to affect dosing decisions for Warfarin. Such a variation was observed in 3% (2/60) in group 1 and 2% (2/100) in group 2. Conclusion: There was good accuracy of the INR obtained with the POCT system used and this was not affected by the timing of the administration of LMWH in relation to testing. Disclosures: No relevant conflicts of interest to declare.

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