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Physiological Reports Oct 2019To compare the effect of 500 mg·kg body mass (BM) sodium citrate ingested in solution or capsules on induced alkalosis, gastrointestinal symptoms and palatability.... (Randomized Controlled Trial)
Randomized Controlled Trial
To compare the effect of 500 mg·kg body mass (BM) sodium citrate ingested in solution or capsules on induced alkalosis, gastrointestinal symptoms and palatability. Twenty-four healthy and active participants completed two testing sessions, ingesting 500 mg·kg BM sodium citrate within solution or capsules. Capillary blood samples were collected pre-ingestion, and every 30-min for 240-min post-ingestion; samples were analyzed for blood pH and [HCO ]. A validated questionnaire was used to quantify gastrointestinal symptoms at the same 30-min intervals. Palatability was quantified immediately after ingestion using a validated scale. There was a greater peak and change from baseline for capsules versus solution for blood pH (P < 0.001) and [HCO ] (P = 0.013). Blood pH and [HCO ] time to peak was 199 and 204 min, respectively, after capsule ingestion, both significantly later than after solution (P = 0.034, P = 0.001). Gastrointestinal symptoms were significantly elevated above baseline for both ingestion modes at each time point between 30 and 120 min after ingestion (P = 0.003), with no differences between modes at any time point (P = 0.644). Capsules were significantly more palatable than solution (P < 0.001). We recommend 500 mg·kg BM sodium citrate ingestion in capsules, at least 200 min before exercise, to achieve greater alkalosis, minimize gastrointestinal symptoms, and maximize.
Topics: Alkalosis; Capsules; Cross-Over Studies; Dietary Supplements; Female; Gastrointestinal Tract; Humans; Male; Sodium Citrate; Taste; Young Adult
PubMed: 31602822
DOI: 10.14814/phy2.14216 -
European Journal of Applied Physiology May 2017This study investigated the effect of induced alkalosis on the curvature constant (W') of the power-duration relationship under normoxic and hypoxic conditions. (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
This study investigated the effect of induced alkalosis on the curvature constant (W') of the power-duration relationship under normoxic and hypoxic conditions.
METHODS
Eleven trained cyclists (mean ± SD) Age: 32 ± 7.2 years; body mass (bm): 77.0 ± 9.2 kg; VO: 59.2 ± 6.8 ml·kg·min completed seven laboratory visits which involved the determination of individual time to peak alkalosis following sodium bicarbonate (NaHCO) ingestion, an environment specific ramp test (e.g. normoxia and hypoxia) and four x 3 min critical power (CP) tests under different experimental conditions. Participants completed four trials: alkalosis normoxia (ALN); placebo normoxia (PLN); alkalosis hypoxia (ALH); and placebo hypoxia (PLH). Pre-exercise administration of 0.3 g.kg BM of NaHCO was used to induce alkalosis. Environmental conditions were set at either normobaric hypoxia (FiO: 14.5%) or normoxia (FiO: 20.93%).
RESULTS
An increase in W' was observed with pre-exercise alkalosis under both normoxic (PLN: 15.1 ± 6.2 kJ vs. ALN: 17.4 ± 5.1 kJ; P = 0.006) and hypoxic conditions (ALN: 15.2 ± 4.9 kJ vs. ALN: 17.9 ± 5.2 kJ; P < 0.001). Pre-exercise alkalosis resulted in a larger reduction in bicarbonate ion (HCO) concentrations during exercise in both environmental conditions (p < 0.001) and a greater blood lactate accumulation under hypoxia (P = 0.012).
CONCLUSION
Pre-exercise alkalosis substantially increased W' and, therefore, may determine tolerance to exercise above CP under normoxic and hypoxic conditions. This may be due to NaHCO increasing HCO buffering capacity to delay exercise-induced acidosis, which may, therefore, enhance anaerobic energy contribution.
Topics: Adult; Alkalosis; Anaerobic Threshold; Exercise; Exercise Tolerance; Humans; Hypoxia; Male; Oxygen Consumption; Sodium Bicarbonate
PubMed: 28280973
DOI: 10.1007/s00421-017-3574-4 -
British Journal of Anaesthesia Aug 2015The influence of common disturbances seen in preeclampsia, such as changes in strong ions and weak acids (particularly albumin) on acid-base status, has not been fully... (Clinical Trial)
Clinical Trial
BACKGROUND
The influence of common disturbances seen in preeclampsia, such as changes in strong ions and weak acids (particularly albumin) on acid-base status, has not been fully elucidated. The aims of this study were to provide a comprehensive acid-base analysis in severe preeclampsia and to identify potential new biological predictors of disease severity.
METHODS
Fifty women with severe preeclampsia, 25 healthy non-pregnant- and 46 healthy pregnant controls (26-40 weeks' gestation), were enrolled in this prospective case-control study. Acid-base analysis was performed by applying the physicochemical approach of Stewart and Gilfix.
RESULTS
Mean [sd] base excess was similar in preeclamptic- and healthy pregnant women (-3.3 [2.3], and -2.8 [1.5] mEq/L respectively). In preeclampsia, there were greater offsetting contributions to the base excess, in the form of hyperchloraemia (BE(Cl) -2 [2.3] vs -0.4 [2.3] mEq/L, P<0.001) and hypoalbuminaemia (BE(Alb) 3.6 [1] vs 2.1 [0.8] mEq/L, P<0.001). In preeclampsia, hypoalbuminaemic metabolic alkalosis was associated with a non-reassuring/abnormal fetal heart tracing (P<0.001). Quantitative analysis in healthy pregnancy revealed respiratory and hypoalbuminaemic alkalosis that was metabolically offset by acidosis, secondary to unmeasured anions and dilution.
CONCLUSIONS
While the overall base excess in severe preeclampsia is similar to that in healthy pregnancy, preeclampsia is associated with a greater imbalance offsetting hypoalbuminaemic alkalosis and hyperchloraemic acidosis. Rather than the absolute value of base excess, the magnitude of these opposing contributors may be a better indicator of the severity of this disease. Hypoalbuminaemic alkalosis may also be a predictor of fetal compromise.
CLINICAL TRIAL REGISTRATION
clinicaltrials.gov: NCT 02164370.
Topics: Acid-Base Imbalance; Alkalosis; Bicarbonates; Case-Control Studies; Female; Humans; Hydrogen-Ion Concentration; Hypoalbuminemia; Pre-Eclampsia; Pregnancy; Prospective Studies
PubMed: 26170350
DOI: 10.1093/bja/aev221 -
Journal of Critical Care Dec 2021Although both the Henderson-Hasselbalch method and the Stewart approach can be used to analyze acid-base disturbances and metabolic and respiratory compensation...
PURPOSE
Although both the Henderson-Hasselbalch method and the Stewart approach can be used to analyze acid-base disturbances and metabolic and respiratory compensation mechanisms, the latter may be superior in detecting subtle metabolic changes.
MATERIALS AND METHODS
We analyzed acid-base disturbances using both approaches in six healthy male volunteers practicing extreme voluntary hyperventilation. Arterial blood gas parameters were obtained during a breathing exercise consisting of approximately 30 cycles of powerful hyperventilation followed by breath retention for approximately 2 min.
RESULTS
Hyperventilation increased pH from 7.39 ± 0.01 at baseline to 7.74 ± 0.06, PaCO decreased from 34.1 ± 1.1 to 12.6 ± 0.7 mmHg, PaO increased from 116 ± 4.6 to 156 ± 4.3 mmHg. Baseline apparent strong ion difference was 42.3 ± 0.5 mEq/L, which decreased to 37.1 ± 0.7 mEq/L following hyperventilation. The strong ion gap significantly decreased following hyperventilation, with baseline levels of 10.0 ± 0.9 dropping to 6.4 ± 1.1 mEq/L.
CONCLUSIONS
Henderson-Hasselbalch analysis indicated a profound and purely respiratory alkalosis with no metabolic compensation following extreme hyperventilation. The Stewart approach revealed metabolic compensation occurring within minutes. These results challenge the long-held axiom that metabolic compensation of acute respiratory acid-base changes is a slow process.
Topics: Acid-Base Equilibrium; Acid-Base Imbalance; Alkalosis, Respiratory; Blood Gas Analysis; Humans; Hydrogen-Ion Concentration; Male
PubMed: 34352585
DOI: 10.1016/j.jcrc.2021.07.019 -
Pediatric Nephrology (Berlin, Germany) Aug 2022
Topics: Acute Kidney Injury; Alkalosis; Child; Humans; Hypercalcemia; Syndrome
PubMed: 35166912
DOI: 10.1007/s00467-022-05465-w -
PloS One 2023Little is known about the long-distance telecoupling effects of urban food demands on land use changes (LUCs) in remote oases of the Southern Sahara. Using the example...
Little is known about the long-distance telecoupling effects of urban food demands on land use changes (LUCs) in remote oases of the Southern Sahara. Using the example of two typical oasis settlements on Mont Bagzam in the southern Aϊr Mountains of Niger which are linked to regional and global markets by an unpaved road since 2015, this study aimed at analyzing time trajectories of LUCs and related changing agricultural production patterns. LUCs were quantified for 1955 to 2022 using GIS-based mapping of agriculture and natural vegetation based on historical aerial photographs, CORONA and multi-spectral satellite images, and high resolution drone-based surveys. The results show a major increment in actively used agricultural land in the 850 ha watershed of the two oases from 11 ha in 1955 to 13 ha in 2003 and 68 ha in 2022 as well as the addition of 92 irrigation wells to 16 existing ones between 2003 and 2022. LUCs and evapotranspiration calculated from climatic data of a local weather station allowed to estimate changes of irrigation water needs in the selected watershed. While annual precipitation averages only 214 mm, local reference evapotranspiration may reach 1,476 mm year-1. Therefore, the additional annual irrigation water needs for the newly established fields between 2003 and 2022 cultivated to cash crops rose by 696 million l. To detect LUC effects on soil quality, soil samples of onion and garlic fields of different ages were collected employing a false-time-series approach. Results reveal increasing soil pH and salt concentrations and falling ground water tables, which reflects a negative water balance and ground water extraction above recharge levels. Our study provides evidence that the newly established telecoupled production systems on Mont Bagzam threaten the sustainability of existing local agricultural production and related livelihoods of agro-pastoralists.
Topics: Cities; Causality; Africa, Northern; Alkalosis; Crops, Agricultural; Garlic
PubMed: 37682955
DOI: 10.1371/journal.pone.0289694 -
BMJ Case Reports Aug 2021A 68-year-old woman presented with right arm cellulitis, not responsive to oral antibiotics. Intravenous antibiotics were commenced, and an ultrasound scan confirmed a...
A 68-year-old woman presented with right arm cellulitis, not responsive to oral antibiotics. Intravenous antibiotics were commenced, and an ultrasound scan confirmed a collection that was surgically drained. She developed refractory hypokalaemia with normal magnesium, no gastrointestinal losses and no iatrogenic cause. She was hypertensive, hyperglycaemic, alkalotic, clinically obese with proximal myopathy and skin bruising. These clinical findings and refractory hypokalaemic hypertension with metabolic alkalosis raised a suspicion of Cushing's syndrome (CS). 24-hour urinary free cortisol (24 hours) was grossly raised on two occasions. The adrenocorticotropic hormone (ACTH) was significantly raised at 154 ng/L, confirming ACTH-dependant CS. A CT scan of the thorax, abdomen and pelvis excluded an ectopic source of hypercortisolaemia. MRI pituitary revealed an invasive macroadenoma. Treatment with endoscopic debulking resulted in the resolution of hypokalaemia and metabolic alkalosis with significant improvement in hyperglycaemia and hypertension.
Topics: Aged; Alkalosis; Cushing Syndrome; Female; Humans; Hydrocortisone; Hypertension; Hypokalemia; Pituitary ACTH Hypersecretion
PubMed: 34446523
DOI: 10.1136/bcr-2021-244850 -
Anesthesiology Apr 1975d-Tubocurarine (dTc) was infused intravenously into 35 cats anesthetized with chloralose and urethane at a constant continuous rate to produce and maintain 90 per cent...
d-Tubocurarine (dTc) was infused intravenously into 35 cats anesthetized with chloralose and urethane at a constant continuous rate to produce and maintain 90 per cent depression of twitch height of the anterior tibial muscle following supramaximal stimulation of the peroneal nerve. The mean infusion rates that produced 90 per cent depression were not significantly altered by respiratory acid-base changes. Metabolic alkalosis decreased (32.5 per cent) and metabolic acidosis increased (27.7 per cent) the required infusion rate of dTc. When pH and Paco2 were maintained at 7.37 and 38 torr, respectively, the addition of a bolus of neostigmine, 10.5 mug/kg, intravenously, to the continuing infusion of dTc produced 50 per cent antagonism of the dTc-depressed twitch. Respiratory alkalosis and metabolic acidosis did not alter the dose of neostigmine needed to produce 50 per cent antagonism. However, during respiratory acidosis (pH 7.13, Paco2 66 torr) and metabolic alkalosis (pH 7.59, Paco2 36 torr) 20.0 and 18.0 mug/kg neostigmine, respectively, were needed to produce 50 per cent antagonism. Still larger doses of neostigmine (75 mug/kg) could not completely antagonize the block unless pH and Paco2 were returned to 7.30-7.50 and 35-45 torr, respectively. It is concluded that respiratory acidosis and metabolic alkalosis limit and oppose antagonism of dTc by neostigmine.
Topics: Acid-Base Equilibrium; Acidosis; Acidosis, Respiratory; Alkalosis; Alkalosis, Respiratory; Anesthesia, Intravenous; Animals; Blood; Carbon Dioxide; Cats; Dose-Response Relationship, Drug; Hydrogen-Ion Concentration; Muscle Contraction; Neostigmine; Partial Pressure; Tubocurarine
PubMed: 235227
DOI: 10.1097/00000542-197504000-00001 -
American Journal of Veterinary Research Oct 2008To determine whether Labrador Retrievers participating in field trials develop respiratory alkalosis and hypocapnia primarily in conditions of high ambient temperatures.
OBJECTIVE
To determine whether Labrador Retrievers participating in field trials develop respiratory alkalosis and hypocapnia primarily in conditions of high ambient temperatures.
ANIMALS
16 Labrador Retrievers.
PROCEDURES
At each of 5 field trials, 5 to 10 dogs were monitored during a test (retrieval of birds over a variable distance on land [1,076 to 2,200 m]; 36 assessments); ambient temperatures ranged from 2.2 degrees to 29.4 degrees C. For each dog, rectal temperature was measured and a venous blood sample was collected in a heparinized syringe within 5 minutes of test completion. Blood samples were analyzed on site for Hct; pH; sodium, potassium, ionized calcium, glucose, lactate, bicarbonate, and total CO2 concentrations; and values of PvO2 and PvCO2. Scatterplots of each variable versus ambient temperature were reviewed. Regression analysis was used to evaluate the effect of ambient temperature (< or = 21 degrees C and > 21 degrees C) on each variable.
RESULTS
Compared with findings at ambient temperatures < or = 21 degrees C, venous blood pH was increased (mean, 7.521 vs 7.349) and PvCO2 was decreased (mean, 17.8 vs 29.3 mm Hg) at temperatures > 21 degrees C; rectal temperature did not differ. Two dogs developed signs of heat stress in 1 test at an ambient temperature of 29 degrees C; their rectal temperatures were higher and PvCO2 values were lower than findings in other dogs.
CONCLUSIONS AND CLINICAL RELEVANCE
When running distances frequently encountered at field trials, healthy Labrador Retrievers developed hyperthermia regardless of ambient temperature. Dogs developed respiratory alkalosis and hypocapnia at ambient temperatures > 21 degrees C.
Topics: Alkalosis, Respiratory; Animals; Blood Chemical Analysis; Blood Glucose; Body Temperature; Dog Diseases; Dogs; Heat Stress Disorders; Hematocrit; Hot Temperature; Hypocapnia; Physical Exertion
PubMed: 18828680
DOI: 10.2460/ajvr.69.10.1262 -
BMC Nephrology Aug 2020Gitelman syndrome is a rare salt-losing renal tubular disorder associated with mutation of SLC12A3 gene, which encodes the Na-Cl co-transporter (NCCT). Gitelman syndrome...
BACKGROUND
Gitelman syndrome is a rare salt-losing renal tubular disorder associated with mutation of SLC12A3 gene, which encodes the Na-Cl co-transporter (NCCT). Gitelman syndrome is characterized by hypokalemia, metabolic alkalosis, hypomagnesemia, hypocalciuria, and renin-angiotensin-aldosterone system (RAAS) activation. Different SLC12A3 variants may lead to phenotypic variability and severity.
METHODS
In this study, we reported the clinical features and genetic analysis of a Chinese pedigree diagnosed with Gitelman syndrome.
RESULTS
The proband exhibited hypokalaemia, hypomagnesemia, metabolic alkalosis, but hypercalciuria and kidney stone formation. The increased urinary calcium excretion made it confused to Bartter syndrome. The persistent renal potassium wasting resulted in renal tubular lesions, and might affect urinary calcium reabsorption and excretion. Genetic analysis revealed mutations of SLC12A3 gene with c.433C > T (p.Arg145Cys), c.1077C > G (p.Asn359Lys), and c.1666C > T (p.Pro556Ser). Potential alterations of structure and function of NCCT protein due to those genetic variations of SLC12A3 are predicted. Interestingly, one sibling of the proband carried the same mutant sites and exhibited similar clinical features with milder phenotypes of hypokalemia and hypomagnesemia, but hypocalciuria rather than hypercalciuria. Family members with at least one wild type copy of SLC12A3 had normal biochemistry. With administration of spironolactone, potassium chloride and magnesium supplement, the serum potassium and magnesium were maintained within normal ranges.
CONCLUSIONS
In this study, we identified compound mutations of SLC12A3 associated with varieties of clinical features. Further efforts are needed to investigate the diversity in clinical manifestations of Gitelman syndrome and its correlation with specific SLC12A3 mutations.
Topics: Adult; Aged; Alkalosis; Bartter Syndrome; China; Female; Genotype; Gitelman Syndrome; Humans; Hypercalciuria; Hypokalemia; Magnesium; Male; Middle Aged; Mutation; Pedigree; Phenotype; Renal Elimination; Solute Carrier Family 12, Member 3; Water-Electrolyte Imbalance
PubMed: 32758178
DOI: 10.1186/s12882-020-01996-2