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1.
J Zoo Wildl Med ; 50(4): 1026-1030, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926542

RESUMO

The Galápagos shearwater, Puffinus subalaris, is a seabird endemic to the Galápagos archipelago. Hematology, blood chemistry, and general health parameters have not been published for this species. Analyses were run on blood samples drawn from 20 clinically healthy Galápagos shearwaters captured by hand at their nests at Islote Pitt on San Cristóbal Island in July 2016. A portable blood analyzer (iSTAT) was used to obtain near immediate field results for pH, pO2, pCO2, TCO2, HCO3 -, hematocrit, hemoglobin, sodium, potassium, chloride, ionized calcium, creatinine, urea nitrogen, anion gap, and glucose. Blood lactate was measured using a portable Lactate Plus analyzer. The reported results provide baseline data that can be used for comparisons among populations and in detecting changes in health status among Galápagos shearwaters.


Assuntos
Bicarbonatos/sangue , Aves/sangue , Dióxido de Carbono/sangue , Hematócrito/veterinária , Oxigênio/sangue , Equilíbrio Ácido-Base , Animais , Glicemia , Cálcio/sangue , Cloretos/sangue , Creatinina/sangue , Hemoglobinas , Concentração de Íons de Hidrogênio , Lactatos/sangue , Potássio/sangue , Sódio/sangue
4.
J Int Soc Sports Nutr ; 16(1): 41, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533750

RESUMO

BACKGROUND: Previous studies have shown that sodium bicarbonate ingestion may enhance intense exercise performance, but may also cause severe gastrointestinal distress. The purpose of this study was to determine whether a modified sodium bicarbonate (SB) ingestion protocol would elevate serum bicarbonate concentration more than previous methods without causing gastrointestinal distress. METHODS: In randomized order, seven (5 men, 2 women) elite middle-distance runners ingested either placebo, Modified SB (600 mg·kg- 1 over 19.5 h), or Acute SB (300 mg·kg- 1) in opaque gelatin capsules. Baseline and post-ingestion blood samples were analyzed for bicarbonate, pH, sodium, hematocrit, and lactate. Repeated measures ANOVA (2 time points × 3 conditions) were analyzed to determine differences in serum bicarbonate, lactate, sodium, blood pH, and hematocrit. Gastrointestinal distress was assessed via self-report on a Likert scale of 1-10. Simple (condition) and repeated (time) within-participant contrasts were used to determine the location of any statistically significant main and interaction effects (p ≤ 0.05). RESULTS: Both Modified SB (7.6 mmol·L- 1, p < 0.01) and Acute SB (5.8 mmol·L- 1, p < 0.01) increased serum bicarbonate concentration compared to the placebo (p ≤ 0.05). Post-ingestion serum bicarbonate concentration was significantly higher for the Modified SB (34.7 ± 2.2 mmol·L- 1, 28.0% increase) trials than the Acute SB (33.5 ± 2.0 mmol·L- 1, 20.9% increase) trials (p = 0.05). There was no reported severe GI distress in the Modified SB trials, but two cases in the Acute SB trials. CONCLUSIONS: Modified SB elevated serum bicarbonate concentration more than Acute SB, without any severe gastrointestinal side effects. Consequently, it is recommended that future experimentation involving SB by researchers and athletes use the novel ingestion protocol described in this study due to its potential for improved effectiveness and reduced gastrointestinal impact. TRIAL REGISTRATION: ClinicalTrials.gov , NCT03813329 . Registered 23 January 2019 - Retrospectively registered.


Assuntos
Bicarbonatos/sangue , Corrida , Bicarbonato de Sódio/administração & dosagem , Adulto , Atletas , Feminino , Gastroenteropatias , Hematócrito , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Masculino , Sódio/sangue , Adulto Jovem
5.
J Int Soc Sports Nutr ; 16(1): 32, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370896

RESUMO

BACKGROUND: The efficacy of sodium citrate supplementation (SC) in exercise performance is unclear. Therefore, the aim of this study was to investigate the effect of SC on skilled tennis performance. METHODS: Ten Brazilian nationally-ranked young male tennis players (age: 17 ± 1 yrs.; stature: 176.7 ± 5.2 cm; body mass: 68.4 ± 7.9 kg) participated in this crossover, placebo-controlled, double-blind study. Upon arrival, at baseline, in both experimental sessions blood was collected, then subjects ingested either sodium citrate (SC - 0.5 g.kg-1BM in capsules of 500 mg) or a placebo (PLA). Two hours later, pre-match blood was collected then skills tests (skill tennis performance test - STPT, repeated-sprint ability shuttle test - RSA) were performed followed by a 1-h simulated match. Immediately following the match, blood was again collected, and STPT, and RSA were administered. RESULTS: All metabolic parameters (i.e. base excess, pH, bicarbonate, and blood lactate) increased (p < 0.001) from baseline to pre-match and post-match in SC condition. Each metabolic parameter was greater (p < 0.001) in SC compared to PLA condition at both pre- and post-match. The SC condition elicited a greater (p < 0.01) shot consistency at post-match in the STPT vs. PLA condition (SC: 58.5 ± 14.8% vs. PLA: 40.4 ± 10.4%). A greater (p < 0.001) amount of games won was observed in the simulated match for SC condition vs. PLA condition (SC: 8.0 ± 1.6 vs. PLA: 6.0 ± 1.7). Additionally, the games won during the simulated match in SC condition was positively correlated with percentage shot consistency (r = 0.67, p < 0.001). CONCLUSIONS: The current findings suggest that SC supplementation is an effective ergogenic aid to enhance skilled tennis performance.


Assuntos
Desempenho Atlético , Substâncias para Melhoria do Desempenho/administração & dosagem , Citrato de Sódio/administração & dosagem , Tênis , Adolescente , Bicarbonatos/sangue , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Humanos , Ácido Láctico/sangue , Masculino , Fenômenos Fisiológicos da Nutrição Esportiva
6.
Clin Lab ; 65(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31414738

RESUMO

BACKGROUND: Accurate chloride measurement is important in critically ill patients. METHODS: Chloride concentration measured simultaneously between the central laboratory (indirect ion-selective electrode) and blood gas analysis (direct ion-selective electrode) were compared. RESULTS: We report a discrepancy with chloride measurement between the central laboratory and blood gas analysis at low bicarbonate levels. CONCLUSIONS: Caution should be applied while interpreting the chloride concentration when indirect ion-selective electrode methodology is used, especially in the setting of low serum bicarbonate levels.


Assuntos
Bicarbonatos/análise , Gasometria/métodos , Cloretos/análise , Estado Terminal , Bicarbonatos/sangue , Gasometria/instrumentação , Cloretos/sangue , Eletrodos , Humanos , Concentração de Íons de Hidrogênio , Potássio/análise , Potássio/sangue , Sódio/análise , Sódio/sangue
7.
J Int Soc Sports Nutr ; 16(1): 18, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987663

RESUMO

BACKGROUND: Past studies have found that sodium bicarbonate ingestion prior to exercise has a performance-enhancing effect on high-intensity exercise. The aim of this study was to investigate the effects of continuous sodium bicarbonate (NaHCO3) supplementation on anaerobic performance during six weeks of high-intensity interval training (HIIT). METHODS: Twenty healthy college-age male participants were randomly assigned to either the HCO3- group (SB) or the placebo group (PL), with 10 subjects in each group. Both groups completed 6 weeks (3 days/week) of HIIT with the SB ingesting an orange-flavored solution containing 15 g xylitol and 0.2 g HCO3-/kg body mass during each training day, and PL ingesting a similar beverage that was HCO3--free. This study separated 6 weeks of training into two stages with different training intensities, with the first 3 weeks at a lower intensity than the second 3 weeks. Blood samples to measure serum HCO3- were obtained 5 min before and 30 min after the following HIIT training sessions: Week 1, training session 1; week 3, training session 3; week 6, training session 3. Three 30s Wingate tests (WAnT) were conducted before, in the middle, and after the training and the supplementation interventions, with peak power, mean power, and fatigue index obtained during WAnT, and blood lactate and heart rate obtained after WAnT. RESULTS: Our findings indicate the following: 1) Serum HCO3- level of SB was significantly higher than PL (p < 0.05) both before and after each HIIT; 2) Relative peak power in WAnT was significantly higher in the SB group after 6 weeks (p < 0.01); 3) Lactate clearance rate and the lactate clearance velocity after 10 min of WAnT were both significantly higher in SB in the post-test (p < 0.01); 4) Heart rate recovery rate at 10 min after WAnT in both SB and PL after 6 weeks were significantly improved (p < 0.01 and p < 0.05, respectively), resulting in no difference between groups on these measures. CONCLUSIONS: These data suggest that supplementation of HCO3- at the level of 0.2 g/kg body mass before HIIT training enhances the effect of HIIT on anaerobic performance, and improves the blood lactate clearance rate and the blood lactate clearance velocity following anaerobic exercise.


Assuntos
Desempenho Atlético , Treinamento Intervalado de Alta Intensidade , Substâncias para Melhoria do Desempenho/administração & dosagem , Bicarbonato de Sódio/administração & dosagem , Limiar Anaeróbio , Bicarbonatos/sangue , Teste de Esforço , Humanos , Ácido Láctico/sangue , Masculino , Adulto Jovem
8.
Nutrients ; 11(4)2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30987297

RESUMO

Despite increasing interest among athletes and scientists on the influence of different dietary interventions on sport performance, the association between a low-carbohydrate, high-fat diet and anaerobic capacity has not been studied extensively. The aim of this study was to evaluate the effects of a low-carbohydrate diet (LCD) followed by seven days of carbohydrate loading (Carbo-L) on anaerobic performance in male basketball players. Fifteen competitive basketball players took part in the experiment. They performed the Wingate test on three occasions: after the conventional diet (CD), following 4 weeks of the LCD, and after the weekly Carbo-L, to evaluate changes in peak power (PP), total work (TW), time to peak power (TTP), blood lactate concentration (LA), blood pH, and bicarbonate (HCO3-). Additionally, the concentrations of testosterone, growth hormone, cortisol, and insulin were measured after each dietary intervention. The low-carbohydrate diet procedure significantly decreased total work, resting values of pH, and blood lactate concentration. After the low-carbohydrate diet, testosterone and growth hormone concentrations increased, while the level of insulin decreased. After the Carbo-L, total work, resting values of pH, bicarbonate, and lactate increased significantly compared with the results obtained after the low-carbohydrate diet. Significant differences after the low-carbohydrate diet and Carbo-L procedures, in values of blood lactate concentration, pH, and bicarbonate, between baseline and post exercise values were also observed. Four weeks of the low-carbohydrate diet decreased total work capacity, which returned to baseline values after the carbohydrate loading procedure. Moreover, neither the low-carbohydrate feeding nor carbohydrate loading affected peak power.


Assuntos
Atletas , Desempenho Atlético , Basquetebol , Dieta com Restrição de Carboidratos , Carboidratos da Dieta/administração & dosagem , Músculo Esquelético/fisiologia , Estado Nutricional , Condicionamento Físico Humano/métodos , Adulto , Bicarbonatos/sangue , Biomarcadores/sangue , Carboidratos da Dieta/metabolismo , Ingestão de Energia , Hormônios/sangue , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Masculino , Contração Muscular , Força Muscular , Músculo Esquelético/metabolismo , Valor Nutritivo , Fatores de Tempo , Adulto Jovem
9.
Med Sci Sports Exerc ; 51(8): 1642-1652, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30817710

RESUMO

PURPOSE: To examine the degree of neuromuscular fatigue development along with changes in muscle metabolism during two work-matched high-intensity intermittent exercise protocols in trained individuals. METHODS: In a randomized, counter-balanced, crossover design, 11 endurance-trained men performed high-intensity intermittent cycle exercise protocols matched for total work and including either multiple short-duration (18 × 5 s; SS) or long-duration (6 × 20 s; LS) sprints. Neuromuscular fatigue was determined by preexercise to postexercise changes in maximal voluntary contraction force, voluntary activation level and contractile properties of the quadriceps muscle. Metabolites and pH were measured in vastus lateralis muscle biopsies taken before and after the first and last sprint of each exercise protocol. RESULTS: Peak power output (11% ± 2% vs 16% ± 8%, P < 0.01), maximal voluntary contraction (10% ± 5% vs 25% ± 6%, P < 0.05), and peak twitch force (34% ± 5% vs 67% ± 5%, P < 0.01) declined to a lesser extent in SS than LS, whereas voluntary activation level decreased similarly in SS and LS (10% ± 2% vs 11% ± 4%). Muscle [phosphocreatine] before the last sprint was 1.5-fold lower in SS than LS (P < 0.001). Preexercise to postexercise intramuscular accumulation of lactate and H was twofold and threefold lower, respectively, in SS than LS (P < 0.001), whereas muscle glycogen depletion was similar in SS and LS. Rate of muscle glycolysis was similar in SS and LS during the first sprint, but twofold higher in SS than LS during the last sprint (P < 0.05). CONCLUSIONS: These findings indicate that, in endurance-trained individuals, multiple long-sprints induce larger impairments in performance along with greater degrees of peripheral fatigue compared to work-matched multiple short-sprints, with these differences being possibly attributed to more extensive intramuscular accumulation of lactate/H and to lower rates of glycolysis during multiple long-sprint exercise.


Assuntos
Treinamento Intervalado de Alta Intensidade , Fadiga Muscular/fisiologia , Músculo Quadríceps/metabolismo , Adulto , Bicarbonatos/sangue , Glicemia/metabolismo , Estudos Cross-Over , Glicogênio/metabolismo , Glicólise , Frequência Cardíaca/fisiologia , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Masculino , Contração Muscular/fisiologia , Fosfocreatina/metabolismo , Resistência Física/fisiologia , Troca Gasosa Pulmonar/fisiologia
10.
J Wildl Dis ; 55(4): 857-861, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30896363

RESUMO

Biochemical and trace element analyses of blood from wild Whooping Cranes (Grus americana) were performed to assess the health of the only self-sustaining, migratory population in North America. Juvenile cranes (n=31) approximately 49-70 d-old were sampled at Wood Buffalo National Park, Northwest Territories, Canada, in midsummer from 2010 to 2012. Archived serum (n=24) and whole blood (n=31) samples from captive juvenile cranes were selected as age-matched controls. Reference values were calculated for serum biochemical analytes and trace elements in whole blood from the captive juvenile Whooping Cranes reared under controlled conditions and with known health histories. Several statistical differences among blood biochemical and trace element values of the wild and captive juveniles were identified and were likely attributable to dietary differences between the populations.


Assuntos
Envelhecimento , Aves/sangue , Oligoelementos/sangue , Equilíbrio Ácido-Base , Fosfatase Alcalina/sangue , Animais , Animais Selvagens , Aspartato Aminotransferases/sangue , Bicarbonatos/sangue , Glicemia , Proteínas Sanguíneas , Cálcio/sangue , Cloretos/sangue , Colesterol/sangue , Creatina Quinase/sangue , L-Lactato Desidrogenase/sangue , Fósforo/sangue , Sódio/sangue , Ácido Úrico/sangue
11.
Lancet ; 393(10179): 1417-1427, 2019 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30857647

RESUMO

BACKGROUND: Patients with advanced chronic kidney disease lose the capacity to fully excrete endogenous acid, resulting in chronic metabolic acidosis that increases the risk of disease progression and causes muscle catabolism and bone resorption. Veverimer, a non-absorbed, counterion-free, polymeric drug, selectively binds and removes hydrochloric acid from the gastrointestinal lumen, unlike current oral sodium bicarbonate therapy for metabolic acidosis that only neutralises accumulated acid. We assessed the efficacy and safety of veverimer as a treatment for metabolic acidosis in patients with chronic kidney disease. METHODS: We did a multicentre, parallel, randomised, double-blind, placebo-controlled study at 37 sites (hospitals and specialty clinics) in Bulgaria, Croatia, Georgia, Hungary, Serbia, Slovenia, Ukraine, and the USA. Eligible participants were patients aged 18-85 years with non-dialysis-dependent chronic kidney disease (estimated glomerular filtration rate of 20-40 mL/min per 1·73 m2) and metabolic acidosis (serum bicarbonate concentration of 12-20 mmol/L). Patients were randomly assigned (4:3) to veverimer 6 g/day or placebo for 12 weeks while they consumed their typical diet. Both drugs were taken as oral suspensions in water with lunch. Randomisation was done by study site personnel with a computer-generated randomisation code with balanced permuted blocks (block size of seven) and stratified by baseline bicarbonate (≤18 mmol/L vs >18 mmol/L). Patients and investigators were masked to treatment allocation; however, because the appearance of placebo differed from veverimer, a non-masked site staff member who had no other role in the study dispensed, prepared, and supervised dosing of the study drugs. The composite primary efficacy endpoint was the difference (veverimer-placebo) in the proportion of patients achieving at week 12 either an increase of 4 mmol/L or more from baseline in serum bicarbonate concentration or serum bicarbonate in the normal range of 22-29 mmol/L, assessed in the modified intention-to-treat population (all patients with a baseline and at least one post-baseline serum bicarbonate value). Patients fasted for at least 4 h (consuming only water) before measurements of bicarbonate. Safety was assessed in all patients who received any amount of study drug. This trial is registered with ClinicalTrials.gov, number NCT03317444. FINDINGS: Between Sept 26, 2017, and Feb 9, 2018, we randomly assigned 124 participants to veverimer and 93 to placebo. The composite primary endpoint was met by 71 (59%) of 120 patients in the veverimer group versus 20 (22%) of 89 patients in the placebo group (a difference of 37%, 95% CI 23-49; p<0·0001). The most common body system in which adverse events in the veverimer group occurred was gastrointestinal; of these, non-treatment limiting diarrhoea was the most common event (11 [9%] vs three [3%] in the veverimer and placebo groups, respectively). The most common treatment-related adverse events were gastrointestinal (diarrhoea, flatulence, nausea, and constipation) occurring in 16 (13%) patients with veverimer and five (5%) patients with placebo. Two deaths occurred during the study, both in the placebo group (unstable angina and pneumonia). INTERPRETATION: Veverimer effectively and safely corrected metabolic acidosis. Longer-term studies are warranted to assess the effects of veverimer on physical functioning and to assess other deleterious consequences of metabolic acidosis including progression of chronic kidney disease and bone health. FUNDING: Tricida.


Assuntos
Acidose/tratamento farmacológico , Ácido Gástrico , Polímeros/uso terapêutico , Insuficiência Renal Crônica/complicações , Acidose/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bicarbonatos/sangue , Reagentes para Ligações Cruzadas/química , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polímeros/química , Resultado do Tratamento
12.
Am J Physiol Renal Physiol ; 316(6): F1244-F1253, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30908932

RESUMO

Acid retention associated with reduced glomerular filtration rate (GFR) exacerbates nephropathy progression in partial nephrectomy models of chronic kidney disease (CKD) and might be reflected in patients with CKD with reduced estimated GFR (eGFR) by increased anion gap (AG). We explored the presence of AG and its association with CKD in 14,924 adults aged ≥20 yr with eGFR ≥ 15 ml·min-1·1.73 m-2 enrolled in the National Health and Nutrition Examination Survey III, 1988-1994, using multivariable regression analysis. The model was adjusted for sociodemographic characteristics, diabetes, and hypertension. We further examined the association between AG and incident end-stage renal disease (ESRD) using frailty models, adjusting for demographics, clinical factors, body mass index, serum albumin, bicarbonate, eGFR, and urinary albumin-to-creatinine ratio by following 558 adults with moderate CKD for 12 yr via the United States Renal Data System. Laboratory measures determined AG using the traditional, albumin-corrected, and full AG definitions. Individuals with moderate CKD (eGFR: 30-59 ml·min-1·1.73 m-2) had a greater AG than those with eGFR ≥ 60 ml·min-1·1.73 m-2 in multivariable regression analysis with adjustment for covariates. We found a graded relationship between the adjusted mean for all three definitions of AG and eGFR categories (P trend < 0.0001). During followup, 9.2% of adults with moderate CKD developed ESRD. Those with AG in the highest tertile had a higher risk of ESRD after adjusting for covariates in a frailty model [relative hazard (95% confidence interval) for traditional AG: 1.76 (1.16-2.32)] compared with those in the middle tertile. The data suggest that high AG, even after adjusting for serum bicarbonate, is a contributing acid-base mechanism to CKD progression in adults with moderate chronic kidney disease.


Assuntos
Equilíbrio Ácido-Base , Taxa de Filtração Glomerular , Falência Renal Crônica/etiologia , Rim/fisiopatologia , Insuficiência Renal Crônica/complicações , Adulto , Idoso , Bicarbonatos/sangue , Biomarcadores/sangue , Estudos Transversais , Progressão da Doença , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Medição de Risco , Fatores de Risco , Estados Unidos , Regulação para Cima , Adulto Jovem
13.
PLoS One ; 14(2): e0211104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30768603

RESUMO

Portable blood gas analyzers are used to facilitate diagnosis and treatment of disorders related to disturbances of acid-base and electrolyte balance in the ambulatory care of equine patients. The aim of this study was to determine whether 2 portable analyzers produce results in agreement with a stationary analyzer. Blood samples from 23 horses hospitalized for various medical reasons were included in this prospective study. Blood gas analysis and electrolyte concentrations measured by the portable analyzers VetStat and epoc were compared to those produced by the cobas b 123 analyzer via concordance analysis, Passing-Bablok regression and Bland-Altman analysis. Limits of agreement indicated relevant bias between the VetStat and cobas b 123 for partial pressure of oxygen (pO2; 27.5-33.8 mmHg), sodium ([Na+]; 4.3-21.6 mmol/L) and chloride concentration ([Cl-]; 0.3-7.9 mmol/L) and between the epoc and cobas b 123 for pH (0.070-0.022), partial pressure of carbon dioxide (pCO2; 3.6-7.3 mmHg), pO2 (36.2-32.7 mmHg) and [Na+] (0.38.1 mmol/L). The VetStat analyzer yielded results that were in agreement with the cobas b 123 analyzer for determination of pH, pCO2, bicarbonate ([HCO3-]) and potassium concentration [K+], while the epoc analyzer achieved acceptable agreement for [HCO3-] and [K+]. The VetStat analyzer may be useful in performing blood gas analysis in equine samples but analysis of [Na+], [Cl-] and pO2 should be interpreted with caution. The epoc delivered reliable results for [HCO3-] and [K+], while results for pH, pCO2, pO2 and [Na+] should be interpreted with caution.


Assuntos
Gasometria/instrumentação , Eletrólitos/sangue , Cavalos/sangue , Animais , Bicarbonatos/sangue , Gasometria/estatística & dados numéricos , Dióxido de Carbono/sangue , Cloretos/sangue , Feminino , Concentração de Íons de Hidrogênio , Masculino , Oxigênio/sangue , Pressão Parcial , Sistemas Automatizados de Assistência Junto ao Leito , Potássio/sangue , Estudos Prospectivos , Reprodutibilidade dos Testes , Sódio/sangue
14.
J Sports Sci ; 37(13): 1499-1505, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30724711

RESUMO

The aim of this study was to investigate the effect of pre-induced inspiratory muscle fatigue (IMF) on race-paced swimming and acid-base status. Twenty-one collegiate swimmers performed two discontinuous 400-m race-paced swims on separate days, with (IMF trial) and without (control trial) pre-induced IMF. Swimming characteristics, inspiratory and expiratory mouth pressures, and blood parameters were recorded. IMF and expiratory muscle fatigue (P < 0.05) were evident after both trials and swimming time was slower (P < 0.05) from 150-m following IMF inducement. Pre-induced IMF increased pH before the swim (P < 0.01) and reduced bicarbonate (P < 0.05) and the pressure of carbon dioxide (PCO2) (P < 0.05). pH (P < 0.05), bicarbonate (P < 0.01) and PCO2 (P < 0.05) were lower during swimming in the IMF trial. Blood lactate was similar before both trials (P > 0.05) but was higher (P < 0.01) in the IMF trial after swimming. Pre-induced IMF induced respiratory alkalosis, reduced bicarbonate buffering capacity and slowed swimming speed. Pre-induced and propulsion-induced IMF reflected metabolic acidosis arising from dual role breathing and propulsion muscle fatigue.


Assuntos
Equilíbrio Ácido-Base , Desempenho Atlético/fisiologia , Fadiga Muscular/fisiologia , Músculos Respiratórios/fisiologia , Natação/fisiologia , Alcalose Respiratória/fisiopatologia , Bicarbonatos/sangue , Dióxido de Carbono/sangue , Feminino , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Masculino , Pressão Parcial , Taxa Respiratória , Adulto Jovem
15.
Biochem Med (Zagreb) ; 29(1): 010709, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30799978

RESUMO

Introduction: A growing number of dialysis patients is treated with home haemodialysis. Our current pre-analytical protocols require patients to centrifuge the blood sample and transfer the plasma into a new tube at home. This procedure is prone to errors and precludes accurate bicarbonate measurement, required for determining dialysate bicarbonate concentration and maintaining acid-base status. We therefore evaluated whether cooled overnight storage of gel separated plasma is an acceptable alternative. Materials and methods: Venous blood of 34 haemodialysis patients was collected in 2 lithium heparin blood collection tubes with gel separator (LH PSTTM II, REF 367374; Becton Dickinson, New Jersey, USA). One tube was analysed directly for measurement of bicarbonate, potassium, calcium, phosphate, glucose, urea, lactate, aspartate aminotransferase (AST), and lactate dehydrogenase (LD); whereas the other was centrifuged and stored unopened at 4 °C and analysed 24 h later. To measure analyte stability after 24 h of storage, the mean difference was calculated and compared to the total allowable error (TEa) which was used as acceptance limit. Results: Potassium (Z = - 4.28, P < 0.001), phosphate (Z = - 3.26, P = 0.001), lactate (Z = - 5.11, P < 0.001) and AST (Z = - 2.71, P = 0.007) concentrations were higher, whereas glucose (Z = 4.00, P < 0.001) and LD (Z = 3.13, P = 0.002) showed a reduction. All mean differences were smaller than the TEa and thus not clinically relevant. Bicarbonate (Z = 0.69, P = 0.491), calcium (Z = - 0.23, P = 0.815) and urea (Z = 0.81, P =0.415) concentrations were stable. Conclusions: Our less complex, user-friendly pre-analytical procedure resulted in at least 24 h stability of analytes relevant for monitoring haemodialysis, including bicarbonate. This allows shipment and analysis the next day.


Assuntos
Coleta de Amostras Sanguíneas , Testes de Química Clínica/normas , Hemodiálise no Domicílio/normas , Bicarbonatos/sangue , Glicemia/análise , Preservação de Sangue , Cálcio/sangue , Testes de Química Clínica/métodos , Hemodiálise no Domicílio/métodos , Humanos , Ácido Láctico/sangue , Potássio/sangue
16.
Am J Kidney Dis ; 73(1): 131-133, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29960797

RESUMO

Four patients were recently seen at our institution presenting with severe hypobicarbonatemia and elevated anion gap on serum specimens processed by an autoanalyzer using enzymatic reactions. Arterial blood gas values in each case revealed no significant acid-base disturbance and a marked discordance between arterial blood gas calculated bicarbonate levels and those reported on the basic metabolic panel. All patients had profound hyperlipidemia (triglycerides > 3,500mg/L), and ultracentrifugation of one patient's serum corrected the discordance. Lipid interference with the photometric measurement of light absorbance after enzymatic reaction in the autoanalyzer is thought to be responsible for the low reported bicarbonate values. Use of an indirect ion-specific electrode method for total carbon dioxide analysis would avoid this pitfall. Caution is advised when enzymatic autoanalyzer-calculated laboratory values are used to diagnose acid-base disturbances in patients with severe hyperlipidemia. Physicians involved in the diagnosis of acid-base disorders in hospitalized patients should always be aware of the method used by their chemistry laboratories to determine total carbon dioxide values.


Assuntos
Desequilíbrio Ácido-Base/sangue , Desequilíbrio Ácido-Base/complicações , Bicarbonatos/sangue , Hiperlipidemias/sangue , Hiperlipidemias/complicações , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Clin Exp Nephrol ; 23(2): 215-222, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30168046

RESUMO

BACKGROUND: Metabolic acidosis, which reduces serum bicarbonate levels, contributes to the progression of chronic kidney disease (CKD). The difference between sodium and chloride (Na-Cl) may theoretically predict serum bicarbonate levels. This study aimed to evaluate serum Na-Cl level as a risk factor for renal function decline among patients who participated in the chronic kidney disease Japan cohort (CKD-JAC) study. METHODS: The association between low Na-Cl concentration (< 34 mmol/L) and composite renal function decline events (any initiation of renal replacement therapy or 50% decline in estimated glomerular filtration rate) was evaluated among 2143 patients with CKD stage G3a-4. Using Cox regression analysis, hazard ratios (HRs) were estimated after adjusting for the following covariates: age, sex, diabetes mellitus, diabetic nephropathy, cardiovascular disease, anemia, angiotensin-converting enzyme inhibitors and angiotensin II receptor antagonists, loop diuretics, cigarette smoking, body mass index, serum albumin, systolic blood pressure, urine albumin-to-creatinine ratio, and CKD stage. RESULTS: Composite renal function decline events were observed in 405 patients (18.9%) over the 4-year follow-up period. Low serum Na-Cl level (< 34 mmol/L) was independently associated with a greater risk for composite renal function decline events (HR 1.384; 95% confidence interval [CI], 1.116-1.717). Subgroup analyses identified that the association between low Na-Cl level and composite renal function decline events was stronger among patients with CKD stage G4 and those with anemia. CONCLUSIONS: Our investigation suggests that Na-Cl is an independent predictor of CKD progression, especially among patients with CKD stage G4 and those with anemia.


Assuntos
Taxa de Filtração Glomerular , Rim/fisiopatologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia , Cloreto de Sódio/sangue , Acidose/sangue , Acidose/fisiopatologia , Idoso , Anemia/sangue , Anemia/fisiopatologia , Bicarbonatos/sangue , Biomarcadores/sangue , Progressão da Doença , Regulação para Baixo , Feminino , Hemoglobinas/metabolismo , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/terapia , Terapia de Substituição Renal , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
19.
Nephrology (Carlton) ; 24(1): 81-87, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29064128

RESUMO

AIM: Correction of metabolic acidosis in patients with chronic kidney disease has been associated with improvement in thyroid function. We examined whether changes in bicarbonate were associated with changes in thyroid function in patients with end-stage renal disease receiving conventional or more frequent haemodialysis. METHODS: In the Frequent Hemodialysis Network Trials, the relationship between changes in serum bicarbonate, free triiodothyronine (FT3) and free thyroxine (FT4) was examined among 147 and 48 patients with endogenous thyroid function who received conventional (3×/week) or more frequent (6×/week) haemodialysis (Daily Trial) or who received conventional or more frequent nocturnal haemodialysis (Nocturnal Trial). Equilibrated normalized protein catabolic rate (enPCR) was examined to account for nutritional factors affecting both acid load and thyroid function. RESULTS: Increasing dialysis frequency was associated with increased bicarbonate level. Baseline bicarbonate level was not associated with baseline FT3 and FT4. Change in bicarbonate level was not associated with changes in FT3 and FT4 in the Daily Trial nor for FT4 in the Nocturnal Trial (r ≤ 0.14, P > 0.21). While, a significant correlation between change in serum bicarbonate and change in FT3 (r = 0.44, P = 0.02) was observed in the Nocturnal Trial; findings were no longer significant after adjusting for change in enPCR (r = 0.37, P = 0.08). For participants with baseline bicarbonate <23 mmol/L, no association between change in bicarbonate and change in thyroid indices were seen in the Daily Trial; for the Nocturnal Trial, findings were also not significant for change in FT3 and the association between change in bicarbonate and change in FT4 (r = 0.54, P = 0.03) was no longer significant after adjusting for enPCR (r = 0.45, P = 0.11). CONCLUSION: Changes in bicarbonate were not associated with changes in thyroid hormone levels after adjusting for enPCR, as a marker of nutritional status. Future studies should examine whether improvement in acid base status improves thyroid function in haemodialysis patients with evidence of thyroid hypofunction.


Assuntos
Equilíbrio Ácido-Base , Bicarbonatos/sangue , Hemodiálise no Domicílio/métodos , Falência Renal Crônica/terapia , Diálise Renal/métodos , Glândula Tireoide/metabolismo , Tiroxina/sangue , Tri-Iodotironina/sangue , Acidose/sangue , Acidose/fisiopatologia , Adulto , Idoso , Biomarcadores/sangue , Feminino , Hemodiálise no Domicílio/efeitos adversos , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Estudos Prospectivos , Desnutrição Proteico-Calórica/sangue , Desnutrição Proteico-Calórica/fisiopatologia , Diálise Renal/efeitos adversos , Glândula Tireoide/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
20.
Korean J Intern Med ; 34(1): 108-115, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30428648

RESUMO

BACKGROUND/AIMS: Many systems including the cardiovascular system (ischemic heart diseases, heart failure, and hypertension) may act as comorbidities that can be seen during the course of chronic obstructive pulmonary disease (COPD). Comorbidities affect the severity and prognosis of COPD negatively. Nearly 25% of patients with COPD die due to cardiovascular diseases. In this study, we aimed to evaluate the relationship between the blood pressure, inflammation, hypoxia, hypercapnia, and the severity of airway obstruction. METHODS: We included 75 COPD patients in the study with 45 control cases. We evaluated age, sex, body mass index, smoking history, C-reactive protein levels, 24-hour ambulatory blood pressure Holter monitoring, arterial blood gas, and respiratory function tests of the patient and the control groups. RESULTS: In COPD patients, the night time systolic, diastolic blood pressures and pulse per minute and the mean blood pressures readings were significantly elevated compared to the control group (p < 0.05). In the correlation analysis, night time systolic pressure was associated with all the parameters except forced expiratory volume in 1 second (FEV1%). Diastolic blood pressure was associated with pH and HCO3 levels. The mean night time, day time pulse pressures and 24- hour pulse per minute values were also associated with all the parameters except FEV1%. CONCLUSION: In this study we found that parameters of systolic and diastolic blood pressures and pulse pressures were significantly elevated in COPD patients compared to the control groups. Blood pressure was associated blood gas parameters and inflammation parameters in COPD patients. This, in turn, may cause understanding of the pathophysiology of COPD and its complications.


Assuntos
Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Bicarbonatos/sangue , Pressão Sanguínea , Proteína C-Reativa/metabolismo , Dióxido de Carbono/sangue , Estudos de Casos e Controles , Feminino , Volume Expiratório Forçado , Frequência Cardíaca , Humanos , Concentração de Íons de Hidrogênio , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Espirometria
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