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Prevention strategies for vasovagal reaction in whole blood donors: A quadri-armed randomised control trial
Meher, R., Patidar, G. K., Chaurasia, R., Pandey, H. C., Hazarika, A.
Transfusion medicine (Oxford, England). 2024
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Editor's Choice
Abstract
INTRODUCTION Vasovagal reaction (VVR) is a frequently encountered generalised donor adverse reaction, associated with donor deterrence towards future donation. Several mitigation strategies for prevention of VVR were tried but still not standardised. This quadri-armed randomised study evaluated the utility of water ingestion, applied muscle tension (AMT) and combination of both in preventing the VVR among blood donors. METHODS A quadri-armed randomised controlled trial was performed on 4320 whole blood donors. Blood donors of 18-65 years of age were randomised into four groups based on the interventions performed i.e., control with no intervention (Group 1, n = 1081), water ingestion (Group 2, n = 1082), AMT (Group 3, n = 1070) and combined intervention (Group 4, n = 1087). VVR during and immediately after blood donation were observed along with assessment of risk factors in blood donors and the effectiveness of interventions were analysed. RESULTS The incidence of VVR observed 1.6% in our study, with the highest occurrence in the control group (2.5%) and the lowest in the combined intervention group (0.9%). Multivariable logistic regression revealed that the control group donors faced a 1.38-fold greater risk of VVR compared to those receiving interventions (OR: 1.38, 95% CI: 1.10-1.75). Other risk factors included younger age (OR: 1.5, 95% CI: 1.05-2.17), first-time donation (OR: 5.7, 95% CI: 1.66-5.74), prior history of VVR (OR: 2.5, 95% CI: 10.4-101.52). DISCUSSION/CONCLUSION The combined approach of water ingestion and AMT proved significantly more effective in VVR prevention compared to individual interventions.
PICO Summary
Population
Whole blood donors (n= 4,320).
Intervention
Water ingestion (n= 1,082). Applied muscle tension (AMT), (n= 1,070). Combination of water ingestion and AMT (combined intervention group, n= 1,087).
Comparison
No intervention (control group, n= 1,081).
Outcome
The incidence of vasovagal reaction (VVR) was 1.6%, with the highest occurrence in the control group (2.5%) and the lowest in the combined intervention group (0.9%). Multivariable logistic regression revealed that the control group donors faced a 1.38-fold greater risk of VVR compared to those receiving interventions (OR 1.38; 95% CI [1.10, 1.75]). Other risk factors included younger age (OR 1.5; 95% CI [1.05, 2.17]), first-time donation (OR 5.7; 95% CI [1.66, 5.74]), and prior history of VVR (OR 2.5; 95% CI [10.4, 101.52]).
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Effects of plasmapheresis frequency on health status and exercise performance in men: A randomized controlled trial
Mortier, A., Khoudary, J., van Dooslaer de Ten Ryen, S., Lannoy, C., Benoit, N., Antoine, N., Copine, S., Van Remoortel, H., Vandekerckhove, P., Compernolle, V., et al
Vox sanguinis. 2023
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Editor's Choice
Abstract
BACKGROUND AND OBJECTIVES Most research studies on the effects of repeated plasma donation are observational with different study limitations, resulting in high uncertainty on the link between repeated plasma donation and health consequences. Here, we prospectively investigated the safety of intensive or less intensive plasma donation protocols. MATERIALS AND METHODS Sixty-three male subjects participated in this randomized controlled trial and were divided into low-frequency (LF, once/month, n = 16), high-frequency (HF, three times/month, n = 16), very high-frequency (VHF, two times/week, n = 16) and a placebo (P, once/month, n = 15) groups. Biochemical, haematological, clinical, physiological and exercise-related data were collected before (D0), after 1½ months (D42) and after 3 months (D84) of donation. RESULTS In VHF, red blood cells, haemoglobin and haematocrit levels decreased while reticulocyte levels increased from D0 to D84. In both HF and VHF, plasma ferritin levels were lower at D42 and D84 compared to D0. In VHF, plasma levels of albumin, immunoglobulin G (IgG), immunoglobulin A (IgA) and immunoglobulin M (IgM) dropped from D0 to D42 and remained lower at D84 than at D0. In HF, plasma IgG, IgA and IgM were lower at D42, and IgG and IgM were lower at D84, compared to D0. Few adverse events were reported in HF and VHF. Repeated plasma donation had no effect on blood pressure, body composition or exercise performance. CONCLUSION VHF plasmapheresis may result in a large reduction in ferritin and IgG levels. HF and VHF plasmapheresis may result in little to no difference in other biochemical, haematological, clinical, physiological and exercise-related parameters.
PICO Summary
Population
Plasmapheresis donors (n= 63).
Intervention
One plasma donation per month (low-frequency (LF) n= 16).
Comparison
Three plasma donations per month (high-frequency (HF) n= 16). Two plasma donations per week (very high-frequency (VHF) n= 16). Placebo (n= 15).
Outcome
Biochemical, haematological, clinical, physiological and exercise-related data were collected before (D0), after one and a half months (D42) and after 3 months (D84) of donation. In VHF, red blood cells, haemoglobin and haematocrit levels decreased while reticulocyte levels increased from D0 to D84. In both HF and VHF, plasma ferritin levels were lower at D42 and D84 compared to D0. In VHF, plasma levels of albumin, immunoglobulin G (IgG), immunoglobulin A (IgA) and immunoglobulin M (IgM) dropped from D0 to D42 and remained lower at D84 than at D0. In HF, plasma IgG, IgA and IgM were lower at D42, and IgG and IgM were lower at D84, compared to D0. Few adverse events were reported in HF and VHF. Repeated plasma donation had no effect on blood pressure, body composition or exercise performance.
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Evaluation of interventions to prevent vasovagal reactions among whole blood donors: rationale and design of a large cluster randomised trial
McMahon, A., Kaptoge, S., Walker, M., Mehenny, S., Gilchrist, P. T., Sambrook, J., Akhtar, N., Sweeting, M., Wood, A. M., Stirrups, K., et al
Trials. 2023;24(1):512
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Editor's Choice
Abstract
BACKGROUND Vasovagal reactions (VVRs) are the most common acute complications of blood donation. Responsible for substantial morbidity, they also reduce the likelihood of repeated donations and are disruptive and costly for blood services. Although blood establishments worldwide have adopted different strategies to prevent VVRs (including water loading and applied muscle tension [AMT]), robust evidence is limited. The Strategies to Improve Donor Experiences (STRIDES) trial aims to reliably assess the impact of four different interventions to prevent VVRs among blood donors. METHODS STRIDES is a cluster-randomised cross-over/stepped-wedge factorial trial of four interventions to reduce VVRs involving about 1.4 million whole blood donors enrolled from all 73 blood donation sites (mobile teams and donor centres) of National Health Service Blood and Transplant (NHSBT) in England. Each site ("cluster") has been randomly allocated to receive one or more interventions during a 36-month period, using principles of cross-over, stepped-wedge and factorial trial design to assign the sequence of interventions. Each of the four interventions is compared to NHSBT's current practices: (i) 500-ml isotonic drink before donation (vs current 500-ml plain water); (ii) 3-min rest on donation chair after donation (vs current 2 min); (iii) new modified AMT (vs current practice of AMT); and (iv) psychosocial intervention using preparatory materials (vs current practice of nothing). The primary outcome is the number of in-session VVRs with loss of consciousness (i.e. episodes involving loss of consciousness of any duration, with or without additional complications). Secondary outcomes include all in-session VVRs (i.e. with and without loss of consciousness), all delayed VVRs (i.e. those occurring after leaving the venue) and any in-session non-VVR adverse events or reactions. DISCUSSION The STRIDES trial should yield novel information about interventions, singly and in combination, for the prevention of VVRs, with the aim of generating policy-shaping evidence to help inform blood services to improve donor health, donor experience, and service efficiency. TRIAL REGISTRATION ISRCTN 10412338. Registration date: October 24, 2019.
PICO Summary
Population
Whole blood donors enrolled in the Strategies to Improve Donor Experiences (STRIDES) trial from all 73 blood donation sites of National Health Service Blood and Transplant (NHSBT) in England (n= 1.4 million).
Intervention
(i) 500ml isotonic drink before donation; (ii) 3-min rest on donation chair after donation; (iii) New modified applied muscle tension (AMT); (iv) Psychosocial intervention using preparatory materials upon arrival and registration.
Comparison
NHSBT’s current practices: (i) 500ml plain water before donation. (ii) 2-min rest on donation chair after donation; (iii) Current practice of AMT; (iv) No psychosocial intervention.
Outcome
The primary outcome is the number of in-session vasovagal reactions (VVRs) with loss of consciousness. Secondary outcomes include all in-session VVRs, all delayed VVRs and any in-session non-VVR adverse events or reactions. Each site ("cluster") has been randomly allocated to receive one or more interventions during a 36-month period, using principles of cross-over, stepped-wedge and factorial trial design to assign the sequence of interventions. Researchers will test the hypothesis that that the implementation of one or more interventions, singly or in combination, will reduce VVRs when compared to current practice in NHSBT.
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Effect of Plasma and Blood Donations on Levels of Perfluoroalkyl and Polyfluoroalkyl Substances in Firefighters in Australia: A Randomized Clinical Trial
Gasiorowski R, Forbes MK, Silver G, Krastev Y, Hamdorf B, Lewis B, Tisbury M, Cole-Sinclair M, Lanphear BP, Klein RA, et al
JAMA network open. 2022;5(4):e226257
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Editor's Choice
Abstract
IMPORTANCE Elevated levels of blood perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been associated with a range of adverse health outcomes. Firefighters have been exposed to PFASs in firefighting foams and have previously been shown to have higher PFAS levels in blood samples than the general population. No interventions have been shown to reduce PFAS levels. OBJECTIVE To examine the effect of blood or plasma donations on PFAS levels in firefighters in Australia. DESIGN, SETTING, AND PARTICIPANTS This 52-week, open-label, randomized clinical trial enrolled participants from May 23 to August 23, 2019. Participants were 285 Fire Rescue Victoria staff or contractors with serum levels of perfluorooctane sulfonate (PFOS) of 5 ng/mL or more who were eligible to donate blood, had not donated blood in the 3 months prior to randomization, and were able to provide written informed consent. Analysis was performed on an intention-to-treat basis from May to July 2021. INTERVENTIONS Firefighters with baseline PFOS levels of 5 ng/mL or more were randomly assigned to donate plasma every 6 weeks for 12 months, donate blood every 12 weeks for 12 months, or be observed only. MAIN OUTCOMES AND MEASURES The primary end points were changes in the serum PFOS and perfluorohexane sulfonic acid (PFHxS) levels after 12 months of plasma or blood donations or after observation only. Secondary end points included changes in serum PFAS levels from week 52 to week 64, changes in other PFASs, and changes in complete blood count, biochemistry, thyroid function, and lipid profile from screening to week 52. RESULTS A total of 285 firefighters (279 men [97.9%]; mean [SD] age, 53.0 [8.4] years) were enrolled; 95 were randomly assigned to donate plasma, 95 were randomly assigned to donate blood, and 95 were randomly assigned to be observed. The mean level of PFOS at 12 months was significantly reduced by plasma donation (-2.9 ng/mL; 95% CI, -3.6 to -2.3 ng/mL; P < .001) and blood donation (-1.1 ng/mL; 95% CI, -1.5 to -0.7 ng/mL; P < .001) but was unchanged in the observation group. The mean level of PFHxS was significantly reduced by plasma donation (-1.1 ng/mL; 95% CI, -1.6 to -0.7 ng/mL; P < .001), but no significant change was observed in the blood donation or observation groups. Analysis between groups indicated that plasma donation had a larger treatment effect than blood donation, but both were significantly more efficacious than observation in reducing PFAS levels. CONCLUSIONS AND RELEVANCE Plasma and blood donations caused greater reductions in serum PFAS levels than observation alone over a 12-month period. Further research is needed to evaluate the clinical implications of these findings. TRIAL REGISTRATION anzctr.org.au Identifier: ACTRN12619000204145.
PICO Summary
Population
Firefighters with baseline serum levels of perfluorooctane sulfonate (PFOS) of 5 ng/mL or more (n= 285).
Intervention
Assigned to donate plasma every 6 weeks for 12 months (n= 95).
Comparison
Assigned to donate blood every 12 weeks for 12 months (n= 95). Assigned to be observed (n= 95).
Outcome
The primary end points were changes in the serum PFOS and perfluorohexane sulfonic acid (PFHxS) levels after 12 months. The mean level of PFOS at 12 months was significantly reduced by plasma donation (-2.9 ng/mL, 95% CI [-3.6, -2.3 ng/mL]), and blood donation (-1.1 ng/mL, 95% CI [-1.5, -0.7 ng/mL]) but was unchanged in the observation group. The mean level of PFHxS was significantly reduced by plasma donation (-1.1 ng/mL, 95% CI [-1.6, -0.7 ng/mL]), but no significant change was observed in the blood donation or observation groups. Analysis between groups indicated that plasma donation had a larger treatment effect than blood donation, but both were significantly more efficacious than observation in reducing PFAS levels.
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A randomized trial of blood donor iron repletion on red cell quality for transfusion and donor cognition and wellbeing
Hod EA, Brittenham GM, Bitan ZC, Feit Y, Gaelen JI, La Carpia F, Sandoval LA, Zhou AT, Soffing M, Mintz A, et al
Blood. 2022
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Editor's Choice
Abstract
Although altruistic regular blood donors are vital for the blood supply, many become iron deficient from donation-induced iron loss. The effects of blood donation-induced iron deficiency on red cell transfusion quality or donor cognition are unknown. In this double-blind, randomized trial, adult iron-deficient blood donors (n=79; ferritin <15 mg/L, and zinc protoporphyrin >60 mMol/mol heme) who met donation qualifications were enrolled. A first standard blood donation was followed by the gold-standard measure for red cell storage quality: a 51-chromium post-transfusion red cell recovery study. Donors were then randomized to intravenous iron repletion (one-gram low molecular weight iron dextran) or placebo. A second donation approximately five months later was followed by another recovery study. Primary outcome was the within-subject change in post-transfusion recovery. The primary outcome measure of an ancillary study reported here was the National Institutes of Health (NIH) Toolbox-derived uncorrected standard Cognition Fluid Composite Score. Overall, 983 donors were screened; 110 were iron-deficient and, of these, 39 were randomized to iron repletion and 40 to placebo. Red cell storage quality was unchanged by iron repletion: mean change in post-transfusion recovery was 1.6% (95% CI -0.5 - 3.8) and -0.4% (-2.0 - 1.2) with and without iron, respectively. Iron repletion did not affect any cognition or wellbeing measures. These data provide evidence that current criteria for blood donation preserve red cell transfusion quality for the recipient and protect adult donors from measurable effects of blood donation-induced iron deficiency on cognition. This trial was registered at www.clinicaltrials.gov as NCT02889133 and NCT02990559.
PICO Summary
Population
Adult iron-deficient blood donors enrolled in the Donor Iron Deficiency Study (DIDS), (n= 79).
Intervention
Intravenous iron repletion (n= 39).
Comparison
Placebo (n= 40).
Outcome
A first standard blood donation was followed by the gold-standard measure for red cell storage quality: a 51-chromium post-transfusion red cell recovery study. Donors were then randomized. A second donation approximately five months later was followed by another recovery study. Primary outcome was the within-subject change in post-transfusion recovery. The primary outcome measure was the National Institutes of Health (NIH) Toolbox-derived uncorrected standard Cognition Fluid Composite Score. Overall, 983 donors were screened; 110 were iron-deficient and, of these, 39 were randomized to iron repletion and 40 to placebo. Red cell storage quality was unchanged by iron repletion: mean change in post-transfusion recovery was 1.6% (95% CI -0.5 - 3.8) and -0.4% (-2.0 - 1.2) with and without iron, respectively. Iron repletion did not affect any cognition or wellbeing measures.
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Effectiveness of Vapocoolant Spray on Venipuncture Pain in Young Male Donors: A Randomized Controlled Trial
Basak, T., Aciksoz, S., Savasci, U., Yilmaz, S.
Journal of Infusion Nursing : The Official Publication of the Infusion Nurses Society. 2021;44(6):339-345
Abstract
The aim of this single-blinded, randomized controlled study was to determine the effectiveness of vapocoolant spray in reducing pain related to venipuncture in young, healthy male blood donors. The participants were separated into 2 groups by randomization. The donors in the control group (n = 44) were not given any intervention during the blood collection process. Vapocoolant spray was applied to the donors in the vapocoolant spray group (n = 44). The pain score was 1.90 ± 1.47 for the vapocoolant spray group and 3.23 ± 2.21 for the control group, and the difference between the groups was found to be statistically significant (P = .02). The study result showed that the use of vapocoolant spray for pain management is an effective method of reducing pain related to venipuncture during the process of blood donation in young male donors.
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Repeat donation and deferral rates in US source plasma donors: Exploratory analysis from the IMPACT trial
Hartmann J, Ragusa MJ, Burchardt ER, Manukyan Z, Popovsky MA, Leitman SF
Transfusion. 2021
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Editor's Choice
Abstract
BACKGROUND The IMPACT trial demonstrated the safety of a new personalized nomogram for plasma donation and provided an opportunity to explore short- to mid-term impact on repeat donation and deferral rates, and factors affecting these. STUDY DESIGN AND METHODS In the IMPACT trial, participants were randomized to donate plasma using an established weight-based nomogram (control) versus a new personalized nomogram incorporating height, weight, and hematocrit (experimental). In this exploratory analysis, repeat donations (per donor, by study arm) were analyzed using negative binomial generalized linear regression models and descriptive statistics. The mean number of donor deferral events was compared between the two arms using logistic regression and count data modeling approaches and were analyzed by lead cause. RESULTS The predicted mean number of repeat donations was similar between the control and experimental arms (6.82 vs. 6.62, respectively; p = .22). Overall, the predicted mean number of repeat donations was significantly higher in males compared with females (p < .0001). Naïve donors had on average 2.8/2.7 (control/experimental) fewer repeat donations compared with experienced donors. In 23, 137 donations from 3443 donors, 798 donors (376 control, 422 experimental, p = .80) had at least one deferral (for any cause). The predicted mean number of deferrals in all categories of interest was not statistically different between the study arms. CONCLUSION Similar repeat donation and deferral rates between arms suggest that the new nomogram did not result in disruptions to subsequent donation. Further longitudinal research on mid- to long-term effects is warranted.
PICO Summary
Population
Plasma donors enrolled in the IMPACT trial (n= 3,443).
Intervention
Personalised nomogram incorporating height, weight, and haematocrit (experimental, n= 1,717).
Comparison
Established weight-based nomogram (control, n= 1,726).
Outcome
The predicted mean number of repeat donations was similar between the control and experimental arms (6.82 vs. 6.62). Overall, the predicted mean number of repeat donations was significantly higher in males compared with females. Naïve donors had on average 2.8/2.7 (control/experimental) fewer repeat donations compared with experienced donors. In 23,137 donations from 3,443 donors, 798 donors (376 control, 422 experimental) had at least one deferral. The predicted mean number of deferrals in all categories of interest was not statistically different between the study arms.
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Social Contagion of Vasovagal Symptoms in Blood Donors: Interactions With Empathy
Mennitto S, Vachon DD, Ritz T, Robillard P, France CR, Ditto B
Annals of behavioral medicine : a publication of the Society of Behavioral Medicine. 2021
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Editor's Choice
Abstract
BACKGROUND Vasovagal reactions (VVRs) are commonly experienced in medical situations such as blood donation. Many believe that psychosocial contagion can contribute to the development of VVRs, but this is largely clinical lore. PURPOSE The goal of the present investigation was to examine the physiological effects of observing another experience a reaction, focusing on the potential moderating effects of empathy. METHODS This study was part of a randomized controlled trial of behavioral techniques on the prevention of VVRs in blood donors. The sample was composed of 530 healthy university students. Measures of symptoms were obtained with the Blood Donation Reactions Inventory (BDRI) and through observation. Physiological variables were measured using respiratory capnometry and a digital blood pressure monitor. The Affective and Cognitive Measure of Empathy was administered to 230 participants. RESULTS Donors who witnessed another experiencing a reaction were more likely to spontaneously report symptoms during the blood draw, to be treated for a reaction, to score higher on the BDRI, and to exhibit smaller compensatory heart rate increases. Donors with higher affective empathy reported more symptoms, exhibited hyperventilation, and were more likely to be treated. Donors with higher cognitive empathy were less likely to require treatment if they witnessed a reaction. CONCLUSION These results suggest that psychosocial contagion of physical symptoms can occur. The moderating effects of empathy differed depending on the subtype of empathy. Perhaps a better cognitive understanding of how other people are feeling functions as a coping response, whereas feeling sympathetic about others' distress increases one's own.
PICO Summary
Population
Blood donors (n= 530).
Intervention
Various comparators of behavioural techniques on the prevention of vasovagal reactions.
Comparison
Outcome
Donors who witnessed another experiencing a reaction were more likely to spontaneously report symptoms during the blood draw, to be treated for a reaction, to score higher on the Blood Donation Reactions Inventory, and to exhibit smaller compensatory heart rate increases. Donors with higher affective empathy reported more symptoms, exhibited hyperventilation, and were more likely to be treated. Donors with higher cognitive empathy were less likely to require treatment if they witnessed a reaction.
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Evaluation of efficacy of Valsalva for attenuating needle puncture pain in first time nonremunerated voluntary plateletpheresis donors: A prospective, randomized controlled trial
Srivastava A, Kumar S, Agarwal A, Khetan D, Katharia R, Mishra P, Khati S, Gautam S, Sandeep K
Asian journal of transfusion science. 2021;15(1):68-74
Abstract
BACKGROUND Plateletpheresis is generally safe but may have adverse reactions. Adverse reactions can negatively influence donor recruitment and retention. Valsalva is a proven method of attenuating pain caused by venipuncture. AIMS The aim was to evaluate the efficacy of the Valsalva maneuver on the attenuation of needle pain and donor anxiety. SETTINGS AND DESIGN This prospective randomized controlled trial was conducted between November 2015 and April 2016 at the Department of Transfusion Medicine. SUBJECTS AND METHODS One-hundred and sixty consecutive donors were grouped into control group (C) and Valsalva group (V) each of sample size 80. The Valsalva group performed a Valsalva maneuver and control did nothing before the venipuncture. Anxiety and pain were scored using a 10 cm visual analog scale (VAS). Severity was graded as VAS = 0 defines no pain and anxiety, VAS = 1-3 as mild pain and anxiety, VAS = 4-6 as moderate pain and anxiety, VAS = 7-9 as severe pain and anxiety, whereas VAS = 10 denotes extreme pain and anxiety. STATISTICAL ANALYSIS Statistical Package for Social Sciences, version 23 was used for analysis. Independent samples t-test/Mann-Whitney U-test was used to compare between treatment and control group, whereas the Wilcoxon signed-rank test was used to test the difference between pre- and postobservations. RESULTS In the Valsalva group, post-Valsalva anxiety levels were significantly reduced to (1 [0-2]) from their pre-Valsalva values of (2 [0-3]); (P < 0.001). Pain was significantly lower (2[1-2]) in Valsalva group compared to control (4[2-5]); (P < 0.001). CONCLUSIONS Valsalva reduced both severity of venipuncture pain and anxiety. Valsalva can be performed by donors as it is an easy, painless, and nonpharmacological method of pain and anxiety attenuation.
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Effect of tourniquet time on whole blood point-of-care lactate concentration: A healthy human volunteer study
Chiew AL, Tran CT, Mackenzie J
Emergency medicine Australasia : EMA. 2021
Abstract
OBJECTIVE Lactate is frequently utilised in clinical practice. Some have concerns that tourniquet application for venous blood collection may falsely elevate venous lactate. The objective of the present study was to determine the effect of tourniquet time on varying venous lactate concentrations. METHODS This is a healthy volunteer study, in which subjects were their own controls. A cannula was inserted into each arm, with a tourniquet remaining on one. Subjects were allocated to one of three groups; rest (no activity), exercise (maximal exertion to elevate lactate concentrations) with immediate tourniquet application or exercise with delayed (5-min post-exercise) tourniquet application. In all blood was drawn simultaneously from both cannulas at 0, 2.5, 5, 10 and 15-min post-tourniquet application and analysed for lactate on a point-of-care device. The primary outcome was a clinically significant difference (>1 mmol/L) in tourniquet versus non-tourniquet arm lactate concentration. RESULTS There were 10 subjects per group; the exercise groups achieved a mean maximum lactate concentration of 10.4 mmol/L (standard deviation [SD] 3.6) (exercise with immediate tourniquet application group) and 8.9 mmol/L (SD 2.5) (exercise with delayed tourniquet application group). There was no clinically significant increase in lactate concentration in the tourniquet compared to non-tourniquet arm in all groups, across all tourniquet application times, and over a range of lactate concentrations. In the rest group after 15-min of tourniquet application the mean lactate concentration of the tourniquet versus non-tourniquet arm was 0.91 mmol/L (SD 0.55) versus 0.89 mmol/L (SD 0.46) (P = 0.99), respectively. CONCLUSION In the present study tourniquet application for blood collection did not significantly increase lactate concentration. Hence, clinically a raised venous lactate concentration should not be attributed to prolonged tourniquet application.