Plasma Lactate Research Articles

Screening and Identification of the Biomarkers Applied for the Evaluation of Acute and Chronic Thermal Tolerance Ability in Largemouth Bass (Micropterus salmoides).

Affected by the continuously rising temperature, thermal stress leads to a delinked growth rate and resistance to stress in cultured largemouth bass (Micropterus salmoides, LMB) in China. Identification of LMB with better thermal resistance will benefit the breeding of new varieties. However, there has been limited reporting on the evaluation to identify LMB with better thermal resistance. LMB consists of the northern LMB (Micropterus salmoides salmoides, NLMB) and the Florida LMB (Micropterus salmoides floridanus, FLMB). Due to their different geographical distributions, it has been suggested that FLMB exhibit better thermal resistance compared to NLMB. In this study, NLMB and FLMB were subjected to thermal stress for 3 h (acute) and 60 d (chronic) at 33 °C, respectively. Subsequently, the variations of 12 candidate biomarkers between NLMB and FLMB were analyzed. Exposure to acute thermal stress significantly increased plasma cortisol, blood glucose, and lactate levels; activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), glucose kinase (GK), pyruvate kinase (PK), lactate dehydrogenase (LDH), and glucose 6 phosphatase (G6Pase); and the expressions of hsp70 and hsp90 in both NLMB and FLMB (p < 0.05). Compared to NLMB, FLMB exhibited a lower plasma cortisol level and a higher expression of hsp90 under acute thermal stress (p < 0.05). Exposure to chronic thermal stress significantly increased plasma cortisol and blood glucose levels, as well as activities of GK, PK, LDH, and G6Pase, as well as expressions of hsp70 and hsp90 in both NLMB and FLMB (p < 0.05). Additionally, FLMB showed a lower expression of hsp70 compared to NLMB (p < 0.05). In conclusion, our results showed that LMB with lower plasma cortisol level and higher expression of hsp90 under acute thermal stress, as well as lower expression of hsp70 under chronic thermal stress were suggested to have better thermal resistance. Our study provides valuable information for identifying and breeding LMB varieties with better thermal resistance in the future.

Point-of-Care Serum Proenkephalin as an Early Predictor of Mortality in Patients Presenting to the Emergency Department with Septic Shock.

The aim of the present study is to investigate the prognostic utility of point-of-care (POC)-measured proenkephalin (PENK), a novel biomarker, in terms of predicting in-hospital mortality in patients presenting to the emergency department (ED) with septic shock. Bedside PENK was measured in consecutive patients presenting to the ED with septic shock according to the Sepsis-3 clinical criteria. The association of PENK with inflammatory and routine biomarkers, and its role as a predictor of in-hospital mortality, was examined. Sixty-one patients with septic shock [53% females, median age 83 years (IQR 71-88)] were evaluated. Median (IQR) values of creatinine, plasma lactate, soluble urokinase plasminogen activator receptor (SuPAR), procalcitonin and PENK were 1.7 (1.0-2.9) mg/dL, 3.6 (2.1-6.8) mmol/L, 13.1 (10.0-21.4) ng/mL, 2.06 (0.84-3.49) ng/mL, and 205 (129-425) pmol/L, respectively. LogPENK significantly correlated with LogLactate (rho = 0.369, p = 0.004), LogCreatinine (rho = 0.537, p < 0.001), LogProcalcitonin (rho = 0.557, p < 0.001), and LogSuPAR (rho = 0.327, p = 0.011). During hospitalization, 39/61 (64%) patients died. In a multivariable logistic regression model, logPENK was an independent predictor of in-hospital mortality (OR 11.9, 95% CI: 1.7-84.6, p = 0.013). POC PENK levels measured upon presentation to the ED strongly correlated with metabolic, renal and inflammatory biomarkers, and may serve as a predictor of in-hospital mortality in patients with septic shock.

Hyperlactataemia is a marker of reduced exercise capacity in heart failure with preserved ejection fraction.

Heart failure with preserved ejection fraction (HFpEF) is associated with an array of central and peripheral haemodynamic and metabolic changes. The exact pathogenesis of exercise limitation in HFpEF remains uncertain. Our aim was to compare lactate accumulation and central haemodynamic responses to exercise in patients with HFpEF, non-cardiac dyspnoea (NCD), and healthy volunteers. Right heart catheterization with mixed venous blood gas and lactate measurements was performed at rest and during symptom-limited supine exercise. Multivariable analyses were conducted to determine the relationship between haemodynamic and biochemical parameters and their association with exercise capacity. Of 362 subjects, 198 (55%) had HFpEF, 103 (28%) had NCD, and 61 (17%) were healthy volunteers. This included 139 (70%) females with HFpEF, 77 (75%) in NCD (P=0.41 HFpEF vs. NCD), and 31 (51%) in healthy volunteers (P<0.001 HFpEF vs. volunteers). The median age was 71 (65, 75) years in HFpEF, 66 (57, 72) years in NCD, and 49 (38, 65) years in healthy volunteers (HFpEF vs. NCD or volunteer, both P<0.001). Peak workload was lower in HFpEF compared with healthy volunteers [52W (interquartile range 31-73), 150W (125-175), P<0.001], but not NCD [53W (33, 75), P=0.85]. Exercise lactate indexed to workload was higher in HFpEF at 0.08mmol/L/W (0.05-0.11), 0.06mmol/L/W (0.05-0.08; P=0.016) in NCD, and 0.04mmol/L/W (0.03-0.05; P<0.001) in volunteers. Exercise cardiac index was 4.5L/min/m2 (3.7-5.5) in HFpEF, 5.2L/min/m2 (4.3-6.2; P<0.001) in NCD, and 9.1L/min/m2 (8.0-9.9; P<0.001) in volunteers. Oxygen delivery in HFpEF was lower at 1553mL/min (1175-1986) vs. 1758mL/min (1361-2282; P=0.024) in NCD and 3117mL/min (2667-3502; P<0.001) in the volunteer group during exercise. Predictors of higher exercise lactate levels in HFpEF following adjustment included female sex and chronic kidney disease (both P<0.001). HFpEF is associated with reduced exercise capacity secondary to both central and peripheral factors that alter oxygen utilization. This results in hyperlactataemia. In HFpEF, plasma lactate responses to exercise may be a marker of haemodynamic and cardiometabolic derangements and represent an important target for future potential therapies.

Dynamic Shift Towards Increased O2 Consumption and Reduced Lactate Uptake During Acute Volume Expansion in Sprague Dawley (SD) Rats

Rationale: In a recent study (PMID: 37575482), we established a method to assess alterations in O2 and substance metabolism in the kidneys in conscious free moving rat. This involved the repeated collection of renal arteriovenous blood and urine, alongside continuous measurements (24/7) of renal blood flow (RBF) and blood pressure (BP). Our previous studies demonstrated that in SD rats, there is an augmentation in RBF and GFR following chronic salt loading. Additionally, total renal O2 consumption (VO2) increases while there is a decrease in the net consumption of lactate with a tendency for its increased production. We hypothesize that these changes are not exclusive to the chronic phase of salt-loading but can also manifest during rapid increases of RBF and GFR. The primary aim of this study was to establish an experimental model reflecting these dynamics. Methods: SD rat (male, 10 wk age fed 0.4 NaCl (LS) diet, n=8) were studied. The jugular vein and femoral vein and artery were catheterized together with the renal vein. FITC-inulin (2 mg/mL) dissolved in 2%BSA saline was infused at 1.0 mL/100 g body wt/h from jugular vein. RBF was measured with an ultrasonic flow probe (Transonic, Inc) on the left renal artery and BP was measured through an arterial catheter. Whole blood, collected from donor rats, was diluted by 20% with saline, and a 6 mL volume expansion was performed with this solution over 1 hour. Blood was collected from both the renal venous and arterial catheters and urine from a ureteral catheter before and after volume expansion. O2 content was measured by radiometer and plasma lactate measured with a high sensitivity L-lactate fluorescent assay kit (ab169557, abcam). The same experiment was performed without volume expansion (i.e., sham study). O2 and lactate delivery and consumption were calculated as follows: Delivery = arterial content (A) x RBF; Consumption = (A − renal venous content (RV)) x RBF; Extraction = (A-RV) / A. Results: BP increased from 101 ± 3 to 111 ± 4 mmHg (p&lt;0.05), RBF increased from 5.4 ± 0.5 to 7.9 to 0.6 mL/min/g kidney weight (gkw) (p&lt;0.05) by volume expansion. GFR increased from 0.94 ± 0.06 to 1.19 ± 0.08 mL/min/gkw (p&lt;0.05). O2 delivery increased from 1.06 ± 0.09 to 1.61 ± 0.12 mL/min/gkw (p&lt;0.05). O2 consumption (VO2) increased from 0.06 ± 0.01 to 0.08 ± 0.01 mL/min/gkw (p&lt;0.05). The O2 extraction ratio remained unchanged. Both lactate consumption (0.94 ± 0.11 to 0.47 ± 0.11 mM/gkw, p&lt;0.05) and extraction ratio (0.18 ± 0.01 to 0.11 ± 0.02, p&lt;0.05) were reduced by volume expansion. Conclusion: The increase of O2 consumption and reduction of lactate consumption with acute volume expansion model appear to be similar to those that we observed when SD rats were subjected to a chronic step increase of salt intake (from 0.4 to 4.0% NaCl). In contrast, however, an increase in O2 extraction was not observed with acute volume expansion as was the case with a high salt diet in which our studies have indicated that a prolonged tubular reabsorptive workload leads to enhanced oxidative stress with an uncoupling of oxidative phosphorylation. R01 HL151587, AHA 23POST1008714. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Evidence-based study of Hridayarnava Rasa: An Ayurvedic formulation in experimentally induced atherosclerotic cardiovascular disease

Abstract BACKGROUND: Ayurvedic medicine provides fundamental knowledge of the concepts and components involved in traditional medicine. Hridayarnava Rasa (H. Rasa) is an Ayurvedic formulation, composed of herbal constituents and metallo-mineral ingredients. Individual components of H. Rasa were reported to treat various ailments; however, very few evidence-based studies on the formulation were available in other aspects of H. Rasa. The present study was focused on the evidence-based assessment of the test of H. Rasa in experimentally induced atherosclerotic cardiovascular disease (ASCVD). METHODS: A total of 24 male New Zealand rabbits were randomly distributed into six groups of four rabbits each. Group I rabbits were fed with a standard pellet diet; group II was induced with ASCVD; groups III, IV, and V were induced with ASCVD plus different doses of H. Rasa, and group VI was induced with ASCVD plus atorvastatin supplementation. RESULTS: Plasma lactate dehydrogenase, creatine kinase, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase, γ-glutamyltransferase, total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDLc), very LDLc, AST:ALT ratio, hydroxy-3-methyl glutaryl coenzyme reductase activity, collagen, and elastin were significantly increased, whereas high-density lipoprotein cholesterol levels were significantly decreased in ASCVD induced group. This was supported by CD68 levels of the aorta by immunohistochemistry. Changes were reversed in H. Rasa-treated groups of different doses of the drug. CONCLUSION: These results suggest that a high-fat diet accelerates the development of ASCVD in a time-dependent manner, and H. Rasa protects the aorta by maintaining the lipids, lipoproteins, and marker enzymes in a dose-dependent manner similar to atorvastatin.

Effect of Acute Sodium Bicarbonate and Caffeine Coingestion on Repeated-Sprint Performance in Recreationally Trained Individuals: A Randomized Controlled Trial.

The acute and isolated ingestion of sodium bicarbonate (NaHCO3) and caffeine (CAF) improves performance and delays fatigue in high-intensity tasks. However, it remains to be elucidated if the coingestion of both dietary supplements stimulates a summative ergogenic effect. This study aimed to examine the effect of the acute coingestion of NaHCO3 and CAF on repeated-sprint performance. Twenty-five trained participants (age: 23.3 [4.0]y; sex [female/male]: 12/13; body mass: 69.6 [12.5]kg) participated in a randomized, double-blind, placebo (PLA) -controlled, crossover study. Participants were assigned to 4 conditions: (1)NaHCO3 + CAF, (2)NaHCO3, (3)CAF, or(4)PLA. Thus, they ingested 0.3g/kg of NaHCO3, 3mg/kg of CAF, or PLA. Then, participants performed 4 Wingate tests (Wt), consisting of a 30-second all-out sprint against an individualized resisted load, interspersed by a 1.5-minute rest period between sprints. Peak (Wpeak) and mean (Wmean) power output revealed a supplement and sprint interaction effect (P = .009 and P = .049, respectively). Compared with PLA, NaHCO3 + CAF and NaHCO3 increased Wpeak performance in Wt 3 (3%, P = .021) and Wt 4 (4.5%, P = .047), while NaHCO3 supplementation increased mean power performance in Wt 3 (4.2%, P = .001). In Wt 1, CAF increased Wpeak (3.2%, P = .054) and reduced time to Wpeak (-8.5%; P = .008). Plasma lactate showed a supplement plus sprint interaction (P < .001) when NaHCO3 was compared with CAF (13%, P = .031) and PLA (23%, P = .021). To summarize, although the isolated ingestion of CAF and NaHCO3 improved repeated-sprint performance, the coingestion of both supplements did not stimulate a synergic ergogenic effect.

Enteral plasma supports brain repair in newborn pigs after birth asphyxia

Newborns exposed to birth asphyxia transiently experience deficient blood flow and a lack of oxygen, potentially inducing hypoxic-ischaemic encephalopathy and subsequent neurological damage. Immunomodulatory components in plasma may dampen these responses. Using caesarean-delivered pigs as a model, we hypothesized that dietary plasma supplementation improves brain outcomes in pigs exposed to birth asphyxia. Mild birth asphyxia was induced by temporary occlusion of the umbilical cord prior to caesarean delivery. Motor development was assessed in asphyxiated (ASP) and control (CON) piglets using neonatal arousal, physical activity and gait test parameters before euthanasia on Day 4. The ASP pigs exhibited increased plasma lactate at birth, deficient motor skills and increased glial fibrillary acidic protein levels in CSF and astrogliosis in the putamen. The expression of genes related to oxidative stress, inflammation and synaptic functions was transiently altered in the motor cortex and caudate nucleus. The number of apoptotic cells among CTIP2-positive neurons in the motor cortex and striatal medium spiny neurons was increased, and maturation of preoligodendrocytes in the internal capsule was delayed. Plasma supplementation improved gait performance in the beam test, attenuated neuronal apoptosis and affected gene expression related to neuroinflammation, neurotransmission and antioxidants (motor cortex, caudate). We present a new clinically relevant animal model of moderate birth asphyxia inducing structural and functional brain damage. The components in plasma that support brain repair remain to be identified but may represent a therapeutic potential for infants and animals after birth asphyxia.

Endocrine data provide further evidence of physiologic derangement in sea turtles affected by the Deepwater Horizon oil spill

This study was conducted to characterize the adrenocortical and thyroid status of Kemp’s ridley sea turtles Lepidochelys kempii that were affected by the Deepwater Horizon oil spill. A plasma aldosterone assay was validated for L. kempii, and it was used along with previously validated assays for corticosterone and free thyroxine to assess hormone concentrations of 30 L. kempii that were hospitalized due to oil exposure, representing 2 severities of oiling (lightly or heavily oiled). Hormone concentrations were also assessed in relation to 8 clinical biochemical analytes. Analysis of paired samples indicated that oiled turtles had significantly higher initial aldosterone and corticosterone concentrations, which declined during convalescence (average 96 and 90% decrease, respectively). Thyroxine concentrations significantly increased between admission and convalescence (average 65% increase). Initial biochemical data indicated significantly higher plasma potassium, ionized magnesium, and lactate concentrations compared to convalescent values. Aldosterone concentrations were positively correlated with corticosterone, negatively correlated with free thyroxine, and variably correlated with several clinical biochemical analytes. Results of this study indicate that L. kempii had robust adrenocortical activity after oiling, capture, and transport to the hospital, regardless of the degree of oiling, resulting in very high plasma concentrations of aldosterone and corticosterone. This study also confirms that aldosterone can be reliably measured in sea turtle plasma samples, providing another diagnostic tool for the physiologic assessment of this Critically Endangered species.

EARLY FLUID PLUS NOREPINEPHRINE RESUSCITATION DIMINISHES KIDNEY HYPOPERFUSION AND INFLAMMATION IN SEPTIC NEWBORN PIGS.

Sepsis is the most frequent risk factor for acute kidney injury (AKI) in critically ill infants. Sepsis-induced dysregulation of kidney microcirculation in newborns is unresolved. The objective of this study was to use the translational swine model to evaluate changes in kidney function during the early phase of sepsis in newborns and the impact of fluid plus norepinephrine resuscitation. Newborn pigs (3-7-day-old) were allocated randomly to three groups: 1) sham, 2) sepsis (cecal ligation and puncture) without subsequent resuscitation, and 3) sepsis with lactated Ringer plus norepinephrine resuscitation. All animals underwent standard anesthesia and mechanical ventilation. Cardiac output and glomerular filtration rate were measured noninvasively. Mean arterial pressure, total renal blood flow, cortical perfusion, medullary perfusion, and medullary tissue oxygen tension (mtPO 2 ) were determined for 12 h. Cecal ligation and puncture decreased mean arterial pressure and cardiac output by more than 50%, with a proportional increase in renal vascular resistance and a 60-80% reduction in renal blood flow, cortical perfusion, medullary perfusion, and mtPO 2 compared to sham. Cecal ligation and puncture also decreased glomerular filtration rate by ~79% and increased AKI biomarkers. Isolated foci of tubular necrosis were observed in the septic piglets. Except for mtPO 2 , changes in all these parameters were ameliorated in resuscitated piglets. Resuscitation also attenuated sepsis-induced increases in the levels of plasma C-reactive protein, proinflammatory cytokines, lactate dehydrogenase, alanine transaminase, aspartate aminotransferase, and renal NLRP3 inflammasome. These data suggest that newborn pigs subjected to cecal ligation and puncture develop hypodynamic septic AKI. Early implementation of resuscitation lessens the degree of inflammation, AKI, and liver injury.

Relationship between Neonatal Cerebral Fuels and Neurosensory Outcomes at 3 Years in Well Babies: Follow-Up of the Glucose in Well Babies (GLOW) Study

Plain Language SummaryIn the Glucose in Well babies and their later Neurodevelopment (GLOWiNg) study, we investigated whether the availability of brain fuels in healthy term babies during the first 5 days after birth was associated with their neurodevelopmental progress at 3 years of age. We had measured plasma glucose, lactate, and beta-hydroxybutyrate concentrations when the children were babies, as these are the most common brain fuels. We used the Ages and Stages questionnaire, which is completed by parents, to assess the child’s development in areas including communication, motor skills (fine and gross), and problem solving.We studied 64 families whose babies were part of the Glucose in Well Babies (GLOW) study in New Zealand. Using both structural equation modelling and linear regression, we found that even though many babies experienced episodes of low plasma glucose concentrations, there was no detectable relationship between these episodes and developmental progress at 3 years of age. We explored other factors, including glucose concentrations, total fuels available, and the duration of low glucose episodes, and found no significant associations. Our results suggest that in healthy term babies, episodes of low glucose concentrations in the first days after birth may be part of the normal metabolic transition after birth and may not have long-term implications for neurodevelopment. However, larger studies using different assessment tools are needed to confirm these findings.

Hydration status and biochemical profile of Quarter Horses in vaquejada training

The hydration status and biochemical profile were assessed and compared in two Quarter Horses groups (pull and helper), at three times (T) of a vaquejada training: at rest, before exercise (T0); after three sprints or races (T1); after an hour of rest from sprints (T2). There was no significant difference between the evaluation times in each group nor between the groups in the times evaluated for the parameters: capillary refill time, skin turgor, color and humidity of the mucosa, total plasma proteins, creatinine, urea and osmolarity, creatine kinase, aspartate aminotransferase, total calcium, phosphorus, and total magnesium. There was increase in the hematocrit and plasma glucose in both groups at T1, but without differences among the groups. The plasm lactate increased in T1. Only for plasma lactate there were changes between the groups, being higher in the pull at T1. It was concluded that, in response to the imposed exercise, the pull and helper groups showed similar hydration status with only slight dehydration, and maintained their biochemical rates preserved, except lactatemia which increased in both, but higher in the pull, suggesting that this group performs more intense anerobic metabolism in the vaquejada.

Effects of restrictive fluid therapy on the time to resolution of hyperlactatemia in ICU patients with septic shock. A secondary post hoc analysis of the CLASSIC randomized trial

PurposeThe aim of this study was to examine the effects of intravenous (IV) fluid restriction on time to resolution of hyperlactatemia in septic shock. Hyperlactatemia in sepsis is associated with worse outcome. Sepsis guidelines suggest targeting lactate clearance to guide fluid therapy despite the complexity of hyperlactatemia and the potential harm of fluid overload.MethodsWe conducted a post hoc analysis of serial plasma lactate concentrations in a sub-cohort of 777 patients from the international multicenter clinical CLASSIC trial (restriction of intravenous fluids in intensive care unit (ICU) patients with septic shock). Adult ICU patients with septic shock had been randomized to restrictive (n = 385) or standard (n = 392) intravenous fluid therapy. The primary outcome, time to resolution of hyperlactatemia, was analyzed with a competing-risks regression model. Death and discharge were competing outcomes, and administrative censoring was imposed 72 h after randomization if hyperlactatemia persisted. The regression analysis was adjusted for the same stratification variables and covariates as in the original CLASSIC trial analysis.ResultsThe hazard ratios (HRs) for the cumulative probability of resolution of hyperlactatemia, in the restrictive vs the standard group, in the unadjusted analysis, with time split, were 0.94 (confidence interval (CI) 0.78–1.14) at day 1 and 1.21 (0.89–1.65) at day 2–3. The adjusted analyses were consistent with the unadjusted results.ConclusionIn this post hoc retrospective analysis of a multicenter randomized controlled trial (RCT), a restrictive intravenous fluid strategy did not seem to affect the time to resolution of hyperlactatemia in adult ICU patients with septic shock.

Clinical Relevance of Plasma Lactic Acid in the Onset and Prognosis of Sudden Deafness.

Sudden deafness poses a significant threat to patients' quality of life, yet effective indicators for evaluating its onset and prognosis remain elusive. The inner ear is primarily supplied by the labyrinthine artery, which lacks collateral circulation. Changes in coagulation function and hemorheology can cause spasm or thrombosis of the labyrinthine artery, leading to ischemia, hypoxia, and microcirculation disorders in the inner ear, ultimately resulting in sudden deafness. This retrospective study examined 196 patients with sudden deafness, utilizing the 2015 Chinese guideline for diagnosis and treatment classification. Coagulation system analysis used the STA-R Evolution automatic coagulation analyzer, measuring activated partial thromboplastin time (APTT), prothrombin time (PT), and fibrinogen (FIB). Plasma lactate concentration was determined using a Johnson and Johnson Fusion 5.1 model plasma lactate detector. Results of the study revealed a correlation between the degree of hearing loss and disease prognosis. Patients with higher grade hearing loss exhibited elevated plasma lactate levels upon admission compared with those with lower grade hearing loss. Importantly, elevated plasma lactate levels at admission served as predictive indicators for treatment outcomes. In addition, patients with ineffective treatment demonstrated a more coagulable blood state, as evidenced by the lower APTT (ineffective treatment: 31.47 ± 4.55 seconds, effective treatment: 35.17 ± 5.38 seconds) and PT on admission, but higher plasma FIB. In conclusion, plasma lactate levels upon admission hold promise as prognostic markers for sudden deafness treatment outcomes, providing valuable insights for clinical management.

Comparative Analysis of Therapeutic Strategies in Post-Cardiotomy Cardiogenic Shock: Insight into a High-Volume Cardiac Surgery Center.

Background: Post-cardiotomy cardiogenic shock (PCCS), which is defined as severe low cardiac output syndrome after cardiac surgery, has a mortality rate of up to 90%. No study has yet been performed to compare patients with PCCS treated by conservative means to patients receiving additional mechanical circulatory support with veno-arterial extracorporeal membrane oxygenation (ECMO). Methods: A single-center retrospective analysis from January 2018 to June 2022 was performed. Results: Out of 7028 patients who underwent cardiac surgery during this time period, 220 patients (3%) developed PCCS. The patients were stratified according to their severity of shock based on the Stage Classification Expert Consensus (SCAI) group. Known risk factors for shock-related mortality, including the vasoactive-inotropic score (VIS) and plasma lactate levels, were assessed at structured intervals. In patients treated additionally with ECMO (n = 73), the in-hospital mortality rate was 60%, compared to an in-hospital mortality rate of 85% in patients treated by conservative means (non-ECMO; n = 52). In 18/73 (25%) ECMO patients, the plasma lactate level normalized within 48 h, compared to 2/52 (4%) in non-ECMO patients. The morbidity of non-ECMO patients compared to ECMO patients included a need for dialysis (42% vs. 60%), myocardial infarction (19% vs. 27%), and cerebrovascular accident (17% vs. 12%). Conclusions: In conclusion, the additional use of ECMO in PCCS holds promise for enhancing outcomes in these critically ill patients, more rapid improvement of end-organ perfusion, and the normalization of plasma lactate levels.

Anaerobic Lactate Production Is Associated With Decreased Microcirculatory Blood Flow and Decreased Mitochondrial Respiration Following Cardiovascular Surgery With Cardiopulmonary Bypass.

Quantify the relationship between perioperative anaerobic lactate production, microcirculatory blood flow, and mitochondrial respiration in patients after cardiovascular surgery with cardiopulmonary bypass. Serial measurements of lactate-pyruvate ratio (LPR), microcirculatory blood flow, plasma tricarboxylic acid cycle cycle intermediates, and mitochondrial respiration were compared between patients with a normal peak lactate (≤ 2 mmol/L) and a high peak lactate (≥ 4 mmol/L) in the first 6 hours after surgery. Regression analysis was performed to quantify the relationship between clinically relevant hemodynamic variables, lactate, LPR, and microcirculatory blood flow. This was a single-center, prospective observational study conducted in an academic cardiovascular ICU. One hundred thirty-two patients undergoing elective cardiovascular surgery with cardiopulmonary bypass. None. Patients with a high postoperative lactate were found to have a higher LPR compared with patients with a normal postoperative lactate (14.4 ± 2.5 vs. 11.7 ± 3.4; p = 0.005). Linear regression analysis found a significant, negative relationship between LPR and microcirculatory flow index ( r = -0.225; β = -0.037; p = 0.001 and proportion of perfused vessels: r = -0.17; β = -0.468; p = 0.009). There was not a significant relationship between absolute plasma lactate and microcirculation variables. Last, mitochondrial complex I and complex II oxidative phosphorylation were reduced in patients with high postoperative lactate levels compared with patients with normal lactate (22.6 ± 6.2 vs. 14.5 ± 7.4 pmol O 2 /s/10 6 cells; p = 0.002). Increased anaerobic lactate production, estimated by LPR, has a negative relationship with microcirculatory blood flow after cardiovascular surgery. This relationship does not persist when measuring lactate alone. In addition, decreased mitochondrial respiration is associated with increased lactate after cardiovascular surgery. These findings suggest that high lactate levels after cardiovascular surgery, even in the setting of normal hemodynamics, are not simply a type B phenomenon as previously suggested.

Venous blood gas and lactate values in adult giraffe trained for voluntary jugular phlebotomy.

Blood gas analyses have previously been performed for giraffe under anesthesia and with physical restraint in a chute; however, reference values for giraffe that are trained to participate in venipuncture without chemical or physical restraint have not previously been described. Using a point-of-care blood gas and lactate analyzer and 20 giraffe trained for voluntary phlebotomy, values were determined for venous blood gasses and plasma lactate concentration. Ninety-five percent confidence in the mean values for venous pH (7.34-7.46), partial pressure of carbon dioxide (PCO2; 28.5-37.8 mmHg), partial pressure of oxygen (PO2; 56-102 mmHg), bicarbonate (HCO3 -; 18.9-21.0 mmol/L), base excess (BE; -6.0 to -3.6 mmol/L), total carbon dioxide (TCO2; 19.9-22.0 mmol/L), and lactate (0.32-0.56 mmol/L) were calculated. This is the first report on venous blood gas analysis values for giraffe without chemical or physical restraint. These data will provide a reference for clinical interpretation of venous blood gas and lactate values in giraffe and demonstrate some of the potential diagnostic benefits to training giraffe and other zoo species for voluntary medical procedures.

Investigative algorithms for disorders affecting plasma lactate dehydrogenase: a narrative review

Investigative algorithms for disorders affecting plasma lactate dehydrogenase: a narrative review

Effectiveness and safety of Shenfu injection in septic patients with hypoperfusion: A multi-center, open-label, randomized, controlled trial

BackgroundTo evaluate the effectiveness and safety of the Shenfu injection (SFI) combined with standard bundle treatment in septic patients with hypoperfusion. MethodThis study was a multi-center, randomized, open-label, controlled trial conducted in four teaching hospitals in China. The septic patients with hypoperfusion and traditional Chinese medicine (TCM) syndrome with Yang-Qi deficiency were enrolled from January 2019, through September 2020. Eligible patients were randomly allocated in a 1:1 ratio to either receive 60 mL of SFI infusion per day plus standard treatment (SFI group) or standard bundle treatment alone (control group). The primary outcome was 28-day all-cause mortality. Secondary outcomes were 90-day all-cause mortality time to weaning from mechanical ventilation, time to weaning from vasopressors, time to discharge from the ICU and hospital, and laboratory results after randomization. ResultsA total of 188 patients completed the trail. This study revealed that the results of the SFI group and the control groups were not statistically significant in 28-day all-cause mortality (10.6% vs. 20.2%, respectively; P=0.106). The infusion of SFI was associated with a significant reduction in the duration of vasopressor use (median=4.0 days, interquartile range [IQR]: 2.0 days–6.0 days vs. median=5.0 days, IQR: 3.0 days–8.0 days, respectively; P=0.043). Patients in the SFI group had statistically greater reductions in plasma lactate levels compared with those in the control group at the first 12 h (median=1.1 mmol/L, IQR: 0.3–2.0 mmol/L vs. median=0.0 mmol/L, IQR: −0.2 to 0.8 mmol/L, respectively; P <0.001) and 24 h (median=1.4 mmol/L, IQR: 0.3–2.2 mmol/L vs. median=0.4 mmol/L, IQR: −0.4 to 1.6 mmol/L, respectively; P=0.001). ConclusionSFI plus standard therapy did not significantly decrease 28-day all-cause mortality for septic patients with hypoperfusion and TCM syndrome with Yang-Qi deficiency.Trial registration Chinese Clinical Trial Registry Identifier: ChiCTR1800020435

Beyond Rest: Exploring the Sleep-Exercise Connection

Introduction The bidirectional relationship between the effects of sleep and exercise is often underappreciated. We aim to explore the bidirectional relationship of sleep and exercise. We further discuss the prominence of poor sleep in both the athletic and general population and understand the underlying mechanisms of interdependencies between the two. The goal is to illuminate practical implications to improve both areas and optimize physical and mental health.Objectives-To explore the bidirectional relationship between sleep and exercise-To understand how exercise can counterbalance the adverse metabolic consequences of sleep deprivation. MethodsWe conducted a systemic literature review from Pubmed, Scopus, and PsychINFO using the search terms: “(exercise) and (sleep),” “(exercise performance) and (sleep),” “(sleep quality) and (exercise).” We included original studies in English conducted on age groups 18 years and older.Results Data from 31 studies shows that a significant number of athletes experience poor sleep quality and daytime sleepiness. 68.5% of Qatar Stars League soccer players and 61% of collegiate athletes in NCAA institutions report daytime fatigue several times a week. Most common causes include overtraining, hectic travel schedules, and sleeping in unfamiliar settings. Studies confirm athletes often sleep less before intense training or competitions. Sleep deficiency may lead to reduced muscular strength and endurance, mood changes, increased perceived effort, impaired cognitive processing, and diminished motor skills. Athletes averaging less than 8 hours of sleep nightly were 1.7 times more prone to injuries. Physiologically, sleep loss alters ventilation, plasma lactate concentration, hormone secretion, and inflammatory responses, hinders muscle glycogen restoration. Extended sleep restriction decreases testosterone levels, which influence muscle mass, energy, bone strength, and more. On the contrary, exercise may counter adverse metabolic impacts of sleep deprivation. High-intensity interval exercise (HIIE) has shown to nullify negative metabolic effects of sleep deprivation, suggesting exercise’s protective potential.Conclusions Sleep and exercise are fundamental to maintaining physical, mental, emotional, and spiritual health. The bidirectional, interdependent relationship can be best utilized by the providers to optimize overall well being. The critical impact of adequate sleep, particularly among athletes, is frequently underestimated. Poor sleep can detrimentally affect performance, amplify injury risks, and disrupt physiological functions, yet contemporary lifestyles often downplay its significance. It is important for healthcare professionals to emphasize a balanced approach to optimize these vital aspects. Continued research can offer strategies that benefit athletes and the broader populace, aiming to uplift daily life functionality.Disclosure of InterestNone Declared

Biological significance and clinical utility of lactate in sepsis.

Sepsis is a global health problem; progression to septic shock is associated with a marked increase in morbidity and mortality. In this setting, increased plasma lactate levels demonstrated to be an indicator of severity and a predictor of mortality, and are usually interpreted almost exclusively as a marker of low tissue perfusion. However, a recent paradigm shift has occurred in the exegesis of lactate metabolism and its biological properties. Indeed, metabolic adaptation to stress, even with an adequate oxygen supply, may account for high circulating lactate levels. Likewise, other pathophysiological consequences of sepsis, such as mitochondrial dysfunction, are associated with the development of hyperlactatemia, which is not necessarily accompanied by low tissue perfusion. Interpreting the origin and function of lactate may be of great clinical utility in sepsis, especially when circulating lactate levels are the basis for resuscitative measures.