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Substituting bicarbonate by acetate in dialysis fluids has been proposed for avoiding precipitation of calcium and magnesium carbonates. However, acetate hemodialysis has been abandoned because of deleterious effects of acetate. Conventional bicarbonate hemodialysis is not totally acetate-free, because 3 to 7 mEq/l of acetic acid are added to the dialysate. Acetate-free hemodialysis is possible with another acid (chlorhydric acid or citric acid) or without acid by using some techniques of low-efficiency hemodiafiltration, as acetate-free biofiltration, which avoids the deleterious effect of blood acidification into the dialyzer. In this paper, advantages and disadvantages of different techniques of acetate-free hemodialysis are discussed., (Copyright © 2010 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.)

Purpose of the Study: Local anesthesia with lidocaine is widely used in surgery of the extremities, particularly for fingers. Injection causes pain. In order to minimize this discomfort, addition of bicarbonate has been used by many authors. Results were however contradictory in relation with the difference of approaches. Our study is based on a randomized comparative series with and without lidocaine alcalinization., Material and Methods: Sixty patients presenting multidigital trauma concerning at least two fingers. For each patient, one finger was anesthetized by lidocaine 2 per cent alone and one by lidocaine 2 per cent plus bicarbonate 8.4 per cent respectively in proportion of 4/5 and 1/5. We compared the intensity of pain during injection by a scale ranging from 0 to 10., Results: Significant difference was found between both groups (p < 0.001), alcalinization appearing to decrease discomfort during injection., Discussion: Mechanism of pain decrease by alcalinization is unclear. It appears that intracellular passage of non ionic form of lidocaine is facilitated by alcalinization. This allows the decrease of latence of lidocaine and relieve pain more rapidly by pain receptors blockade., Conclusion: Diminution of pain during anesthetic injection has major advantage in out-patient surgery of extremities, in ligamentar testing of digital articulations and in steroid injection.

Antacid activity supported by citrate-bicarbonate complex of four effervescent ranitidine forms has been assessed in vitro using an 'artificial stomach-duodenum' model controlled by microcomputer. This model allows (i) maintenance of constant the rates of the fluxes throughout the experiments or (ii) simulation of gastroduodenal flux regulation, in the normal subject (NS) or in the duodenal ulcer patient (DU) situation. The four forms developed a theoretical maximal antacid capacity between 61 and 81 mmol with a maximum intragastric pH between 3.2 and 4.8. In the gastroduodenal flux regulation simulation, antacid activity duration was rapid and included between 85 and 118 min in NS situation (50 to 56 mmol H+ consumed) and between 75 and 93 min in DU situation (43 to 47 mmol H+ consumed). The reduction of acid load penetrating into the duodenum was contained between 36 and 50 per cent. Effervescent compounds exerted a neutralising activity and a buffering capacity close to pH 6.0 (5 per cent of total antacid capacity), related to antacid potency.

Bicarbonate administration during lactic acidosis seems logical in view of the myocardial depression associated with the decrease in intracellular pH. This treatment has been recently challenged on the basis of observations showing an increase in the veno-arterial gradient for CO2 during acute circulatory failure. The partial transformation of bicarbonate in CO2 carries the risk of aggravating the phenomenon and thereby decreasing intracellular pH. Alternatives to sodium bicarbonate--carbicarb, THAM and dichloroacetate--are discussed.

An open multicenter study was performed to assess the efficacy and safety of alginic acid in two different dosages in 76 pediatric patients with gastroesophageal reflux confirmed by pH monitoring. Among the 69 patients in whom endoscopy was carried out before treatment, 18 had erythematous esophagitis and 5 had erosive esophagitis. Irrespective of the dosage used, the frequency of regurgitation and vomiting decreased significantly (p < 0.00001 and p = 0.01, respectively). Clinical and biochemical tolerance were outstanding and no adverse effects were recorded. On the basis of these data, the recommended dosage is 1 to 2 ml/kg/day in divided doses after meals.

The authors report a series of nine reno-ureteral obstructive uric acid calculi initially treated by percutaneous nephrostomy. After attempting stone dissolution by in situ alkalinization, they discuss the place of such a method among the various treatments for uric acid stones.

The popularity of polishing air devices (AP) is rising with the increased distribution of commercial units in both United States and European dental offices and clinics. The instrument's efficiency and effectiveness in stain removal has been demonstrated with minimal impact on soft tissue trauma and abrasion. This article reviews the literature on AP. Future research is indicated to explore surgical clinical applications of airpowder polishing as well as more detailed information regarding the biological basis for its use.

The metabolic alkalosis, induced by the administration bicarbonate, reduces adrenaline hyperglycemia in fasted dog.

Specific problems during fabrication of concentrated hemodialysis solutions containing bicarbonate arise because of the low solubility of sodium bicarbonate in water and the risk or precipitation of calcium, magnesium carbonates. These problems have been solved by the Pharmacie centrale by making 2 different concentrated solutions, the first one brinding the major essential elements, at the exclusion of bicarbonate, the second less concentrated, with bicarbonate and potassium gluconate, the latter complexing iron and so preventing precipitates of ferric carbonate. The various pharmaceutical steps are described in this paper: formulation, choice of raw materials and manufacturing processes, quality control.

In two groups of children with diabetic ketoacidosis, the effects of intramuscular insulin injections associated with intensive rehydration and alkalisation were compared with low-dose continuous intravenous infusion associated with well-controlled fluid and electrolyte therapy. Although correction of ketoacidosis was as effective with both methods, the second appeared to offer several advantages: 1. More progressive normalization of metabolic parameters; 2. Reduced risks of hypoglycemia and hypokaliemia; 3. Easier control of the decrease in plasma glucose levels; 4. Better correction of hyponatremia; 5. More gradual increase in pH values. These results confirmed that low-dose continuous insulin infusion with proper monitoring of fluid and electrolyte replacement was a safe, simple and effective treatment of diabetic ketoacidosis in children.

Dissolution of uric acid calculi could be obtained by oral or parenteral urinary alcalinization, but this method cannot apply to the case of obstructive calculi. Nineteen obstructive calculi in 18 patients were treated by in situ alcalinization through a percutaneous nephrostomy catheter (PCN). Eight patients were initially anuric, 7 of whom from an obstructed solitary kidney and 1 from a bilateral obstructive lithiasis. Fifteen calculi were located in the ureter, 3 in the uretero-pelvic junction and 1 in the pelvis. After 48 h of urinary diversion through PCN, an isotonic sodium bicarbonate solution (14 g %) was continuously infused at an average flow rate of 2.8 l/24 h, through either an unique PCN, or a 2 PCN-irrigation circuit in the 7 cases with permanently obstructive calculus. Fifteen calculi (80%) were completely dissolved after 3 to 13 days of alcalinization (average 5.8 days). One large calculus was reduced by 3/4 and further removed by percutaneous lithotripsy. Three patients underwent ureterotomy after 9 to 11 days of uneffective treatment. Local alcalinization is an effective and non invasive treatment for obstructive uric acid calculi, and is logically associated with the necessary urinary diversion.

Following the introduction of one or two percutaneous nephrostomy drains, 16 obstructive uric acid calculi were treated by perfusion of excretory cavities with 14% sodium bicarbonate solution. Twelve calculi had dissolved within an average of 5 days, 1 required percutaneous lithotripsy because of incomplete dissolution and 3 were unaltered. Success of this treatment appears to be dependent on the total radiotransparency of calculi, a feature difficult to demonstrate. There were no reports of major complications. The only weakly invasive nature of alkalinization in situ makes it a method of choice to be reserved for obstructive calculi, and a therapeutic strategy is proposed.

Renewed interest in bicarbonate as the dialysate base replacement during hemodialysis has introduced new settings on acetate-dialysate delivery systems commercially available. Numerous technical problems are associated with unstable bicarbonate solutions. Therefore, several precautions must be observed: 1) Bicarbonate dialysis requires two concentrates: one containing the base replacement bicarbonate and the other containing basically calcium and magnesium chlorides, 2) A two-stream proportioning system afforded by an appropriate dialysate delivery machine should be used to mix the bicarbonate and acid concentrates, in order to ensure on-line production of the final dialysate, 3) Additional monitors, such as pH monitor, are required to prevent misuse of concentrates. These new ancillary equipments and the relatively high cost of bicarbonate concentrates could slow down the extension of bicarbonate dialysis which is potentially beneficial for all dialysis patients.

Three cases of necrotizing and calcifying lesions of low urinary tract, buttock and adjacent perineum are reported. These lesions have been induced by direct syringe injection into an umbilical artery of 42% sodium bicarbonate solution at the dose of 5 to 6 ml/kg of body weight. Radiographic examinations are very important to study the urinary tract lesions. These have been surgically controlled in two cases. The follow up ranges from 10 to 21 1/2 months. On the bladder initial necrotizing lesions are followed by calcification and parietal retraction. These bladder lesions induce a more or less important ureterohydronephrosis. To these constant lesions are variably associated urethral calcifications and stenosis, distal ureter calcifications. These lesions seem to be related to the sodium bicarbonate hyperosmolality, to the injection conditions, and to the local hemodynamic features.