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PubMed1991

Hemodynamic and electrophysiological actions of cocaine. Effects of sodium bicarbonate as an antidote in dogs.

BACKGROUND: Cocaine abuse has been implicated as a cause of death due to sudden cardiac arrest. METHODS AND RESULTS: We examined the hemodynamic and electrophysiological effects of cocaine administered as a series of 5-mg/kg i.v. boluses coupled with a continuous infusion in anesthetized dogs. Sodium bicarbonate (50 meq i.v.) was administered as a potential antidote in 11 of 15 dogs, and intravenous 5% dextrose was given in the remaining four. In a dose-dependent fashion, cocaine significantly decreased blood pressure, coronary blood flow, and cardiac output; increased PR, QRS, QT, and QTc intervals and sinus cycle length; and increased ventricular effective refractory period and dispersion of ventricular refractoriness. No afterdepolarizations were noted in the monophasic action potential recording. Nonsustained monomorphic ventricular tachycardia occurred spontaneously in two dogs, and sustained ventricular tachycardia could be induced by programmed stimulation at the end of the dosing protocol in five of 11 animals. Sodium bicarbonate promptly decreased cocaine-induced QRS prolongation to nearly that measured at baseline but had no effect on the other electrocardiographic or hemodynamic variables. In one dog, sodium bicarbonate administration was associated with reversion of ventricular tachycardia to sinus rhythm. CONCLUSIONS: We conclude that high-dose cocaine possesses negative inotropic and potent type I electrophysiological effects. Sodium bicarbonate selectively reversed cocaine-induced QRS prolongation and may be a useful treatment of ventricular arrhythmias associated with slowed ventricular conduction in the setting of cocaine overdose.

Animals↗
PubMed1982

Cytosine arabinoside stability in intravenous admixtures with sodium bicarbonate and in plastic syringes.

The increased use of high-dose cytarabine in the treatment of neoplasms prompted this study on the reconstituted stability of cytarabine in intravenous admixtures with sodium bicarbonate and in plastic syringes. The study of the effect of sodium bicarbonate was prompted by the frequent use of this agent in patients being treated with cytarabine as a means of achieving systemic alkalinization in order to manage hyperuricemia. The stability of reconstituted cytarabine in plastic syringes was measured to determine whether cytosine arabinoside could be reconstituted and stored prior to use. The results of this study indicate that sodium bicarbonate 50 mEq/L in the intravenous solution containing cytarabine has no effect on the chemical stability of cytarabine for at least one week at room temperature or in the refrigerator. Consequently sodium bicarbonate and cytarabine can be coadministered in one intravenous solution. The reconstituted stability of cytarabine at 20 mg/ml and 50 mg/ml is not affected by storage in plastic syringes.

Bicarbonates↗
PubMed1990

Inhibition by intravenously administered sodium bicarbonate of neuronal activity in medial vestibular nucleus neurons.

The effects of 7% sodium bicarbonate on medial vestibular nucleus (MVN) neurons were examined to elucidate the mechanism underlying its anti-vertigo action, using alpha-chloralose-anesthetized cats. Intravenous injection of the drug at 1, 2 and 4 ml/kg every 10 min dose-dependently inhibited rotation- and glutamate-induced firing of type 1 neurons, although a low dose of the drug enhanced firing in a few neurons. However, microiontophoretic application of bicarbonate ions did not inhibit rotation- or glutamate-induced firing. After injection of the drug, the Po2 level in arterial blood did not differ from previous levels, but the bicarbonate ion levels dose-dependently increased concomitantly with an increase in pH, as compared with previous levels. These results suggest that the intravenous injection of 7% sodium bicarbonate directly inhibits the neuronal activity of the MVN, although the lower dose may enhance neuronal activity by acting on the peripheral vestibule.

Animals↗
PubMed1993

Carbicarb, sodium bicarbonate, and sodium chloride in hypoxic lactic acidosis. Effect on arterial blood gases, lactate concentrations, hemodynamic variables, and myocardial intracellular pH.

The effects of Carbicarb, sodium bicarbonate, and sodium chloride on arterial blood gases, lactate concentrations, hemodynamics, and myocardial intracellular pH were compared in hypoxic lactic acidosis with controlled carbon dioxide elimination. Twenty-one young mongrel dogs were anesthetized, mechanically ventilated, and randomly allocated into one of three treatment groups. After hypoxic lactic acidosis was induced and maintained, 2.5 mEq/kg of one of the agents was infused over 30 min. Arterial blood gases, pH, lactate concentrations, and hemodynamic variables were measured immediately prior to the infusion of the agent and 30 min after the infusion was completed. With sodium bicarbonate administration, there was a significant increase in arterial PCO2 as compared to both Carbicarb or sodium chloride administration. With Carbicarb administration, there was a significant increase in arterial pH, base excess, and cardiac index, without a significant increase in arterial lactate concentration as compared to sodium bicarbonate or sodium chloride administration. Stroke volume index was also increased significantly with decreased heart rate. The data suggest that Carbicarb administration in hypoxic lactic acidosis improved hemodynamics compared with sodium bicarbonate or sodium chloride administration. The increased stroke volume and cardiac contractility appear to be due to improved myocardial intracellular pH.

Acidosis, Lactic↗
PubMed1987

The use of sodium bicarbonate and hydrogen peroxide in periodontal therapy: a review.

The comparative benefits from the use of sodium bicarbonate and hydrogen peroxide over the use of a commercial dentifrice in periodontal therapy is controversial. The consensus of the clinical research indicates that application by patients of sodium bicarbonate and hydrogen peroxide offers no advantage over the preestablished, properly performed home oral hygiene procedures. Any improvements in clinical and microbial parameters generally were attributed to scaling and root planing. The studies that have reported beneficial results with sodium bicarbonate and hydrogen peroxide have used additional antimicrobial agents, concomitant professional application of these substances, and scaling and root planing. In one of these reports, inorganic salts and chloramine-T were delivered subgingivally throughout root-planing procedures, in addition to home application of inorganic salts. Most of these patients also received at least one course of systemic tetracycline therapy. Because this study had no control group, it is impossible to determine whether this program is more effective than are other periodontal therapy programs. A more controlled clinical study involving professional application of sodium bicarbonate, sodium chloride, hydrogen peroxide, and povidone-iodine has shown greater gains in clinical attachment and bone mass than has brushing with toothpaste and water. Again, subgingival scaling and root planing were necessary to attain these results. Because multiple topical agents were applied in both of these reports and systemic antimicrobial agents were used by the Keyes group, it is impossible to determine which agent was responsible for the improvements. Further, professional application may be the crucial factor.(ABSTRACT TRUNCATED AT 250 WORDS)

Bicarbonates↗
PubMed1991

Effects of urea and sodium bicarbonate supplementation of a high-fiber diet on nutrient digestion and ruminal characteristics of defaunated sheep.

Five sheep (average BW 48 kg) with ruminal, duodenal, and ileal cannulas were fed 63% roughage: 37% concentrate diets (CP = 14.5%) in a 5 x 5 Latin square design to study effects of urea and sodium bicarbonate supplementation on nutrient digestion and ruminal characteristics of defaunated sheep. Diets were fed twice daily (DMI = 1,076 g/d). Defaunation was accomplished with 25-ml doses of alkanate 3SL3/sheep daily for 3 d. Control sheep were faunated (Treatment 1) and fed soybean meal as the major N supplement. Remaining sheep were maintained defaunated and fed either the same diet as Treatment 1 (Treatment 2), Treatment 1 with urea replacing 30% of the soybean meal N (Treatment 3), or Treatment 1 with 2% sodium bicarbonate in the diet (Treatment 4). Treatment 5 was a combination of Treatments 3 and 4. Compared with the faunated control, defaunation decreased (P less than .05) total tract DM, OM, NDF, ADF, and CP digestibilities (71.5 vs 69.4, 73.8 vs 71.7, 64.6 vs 61.4, 58.7 vs 55.8, and 74.2 vs 70.6%, respectively) and average (2 to 12 h postfeeding) ruminal fluid ammonia (23.5 vs 13.7 mg/dl) and isobutyrate (.9 vs .7 mM) concentrations. However, defaunation increased (P less than .05) linoleic and linolenic acid flows (.58 vs .45 g C18:2/d; .17 vs .14 g C18:3/d) to and disappearance (.50 vs .39 g C18:2/d; .14 vs .11 g C18:3/d) from the small intestine. Urea supplementation increased (P less than .05) total tract DM (70.2 vs 68.6%) and OM (72.3 vs 71.0%) digestibilities of defaunated sheep but lowered (P less than .05) ruminal fluid isobutyrate concentration (.6 vs .8 mM). Sodium bicarbonate supplementation increased (P less than .05) ruminal fluid pH (6.4 vs 6.2), isobutyrate concentration (.75 vs .60 mM), total tract ADF digestibility (57.6 vs 54.2%), and ruminal NDF (41.6 vs 28.5%), ADF (36.6 vs 22.8%), and CP (-5.5 vs -26.8%) digestibilities in defaunated sheep. Dietary supplementation of urea or sodium bicarbonate increased nutrient digestion by defaunated sheep.

Absorption↗
PubMed1985

Effects of sodium bicarbonate on nitrogen balance, bacterial protein synthesis and sites of nutrient digestion in sheep.

Two experiments were conducted to determine effects of sodium bicarbonate (NaHCO3) on nitrogen (N) balance, ruminal N metabolism and site and extent of nutrient digestion in sheep fed 75% concentrate diets. A 2 X 2 factorial arrangement of treatments was employed in both trials with experimental diets balanced for 10.5 or 12.0% crude protein and containing 0 or 3.5% NaHCO3. In experiment 1, 12 lambs were allotted to four diets for two periods in a randomized complete-block design. Dry matter (DM) digestibility was increased (P less than .10) by NaHCO3 supplementation, but organic matter (OM) digestibility was unaffected by treatment. Apparent N digestibility was not affected by NaHCO3 addition but was increased (P less than .0001) at the higher level of protein. Ruminal pH (4 h postfeeding) was increased (P less than .01) by NaHCO3 supplementation. Sodium bicarbonate had no effect on molar proportions of acetate or propionate, but increased molar proportion of butyrate (P less than .10) in ruminal fluid. Mean N retention (g/d) was increased (P less than .05) at the higher protein level, but was not affected by NaHCO3. In experiment 2, four ruminal- and duodenal-cannulated wethers were utilized in a 4 X 4 Latin square design. Sodium bicarbonate addition increased ruminal pH (P less than .05) 2 h postfeeding but did not affect ruminal ammonia (NH3) levels, total VFA concentration or ruminal fluid dilution rates. Molar proportion of acetate was increased (P less than .01) by NaHCO3 at the lower protein level. Ruminal particulate dilution rates were increased (P less than .05) by NaHCO3 addition. Ruminal, postruminal and apparent total tract digestibilities of OM and neutral detergent fiber (NDF) were unaffected by NaHCO3 supplementation. Sodium bicarbonate decreased (P less than .05) ruminal starch digestion at the lower protein level but increased (P less than .05) it at the higher protein level. Bacterial N flow (g/d) at the duodenum and efficiency of bacterial protein synthesis were increased (P less than .10) by NaHCO3 additions.

Animal Nutritional Physiological Phenomena↗
PubMed1982

Lactating dairy cow responses to dietary sodium, chloride, and bicarbonate during hot weather.

Twelve Holstein and eight Jersey cows in the first half of lactation were assigned to one of four concentrate formulations to provide supplemental sodium salts in the total diet dry matter of 1) .5% sodium chloride, 2) .5% sodium chloride plus .72% sodium bicarbonate, 3) .5% sodium chloride plus .72% sodium bicarbonate, and 4) 1.44% sodium bicarbonate to measure effects on body temperature and respiration rate, milk yield and composition, and blood components that reflect acid-base balance. After data were adjusted for body weight, age, and a covariate based on differences within individuals in the standardization period, they were analyzed with a model that included breed, treatment, week, temperature-humidity index, and interactions. Cow fed sodium bicarbonate and no supplemental sodium chloride had lower body temperatures than the other groups. High sodium and chloride in basal diet and drinking water prevented the large change in dietary amount and ratio of these two electrolytes that treatments were designed to impose. More stringent control of dietary amounts and greater heat stress will be necessary to show effects of these elements on acid-base balance.

Animals↗
PubMed1984

Influence of colostrum preservation and sodium bicarbonate on performance of dairy calves.

Forty-eight Holstein calves were fed one of four liquid diets from 3 to 30 days of age to compare sodium benzoate, propionic acid, and formaldehyde as preservatives for colostrum. Colostrum batches were fermented at temperatures of 20 degrees C or higher. Diets were 2.73 kg of 1) naturally fermented colostrum, or colostrum treated with 2) sodium benzoate (.5% by weight), 3) propionic acid (1.0% by weight), or 4) formaldehyde (.05% by weight). Colostrum diets were diluted with .91 kg water. Prior to feeding, 25 g. sodium bicarbonate was added to liquid diets of one-half the calves on each treatment. Liquid diets were fed once daily. Water and a 15% crude protein complete starter were offered for ad libitum consumption. Calves were weaned abruptly at 30 days of age and received only water and starter from 31 to 44 days of age. Daily gain from 0 to 4 wk and 0 to 6 wk favored calves fed colostrum treated with sodium benzoate or propionic acid. Gains from 0 to 6 wk were .33, .44, .45, and .32 kg/day for the four diets, and feed efficiencies (kg dry matter intake/kg gain) were 3.23, 2.36, 2.76, and 2.89 during the same period. Addition of sodium bicarbonate to colostrum diets improved intake during the 1st wk of feeding. Gain and feed efficiency were similar during wk 0 to 4 but favored slightly calves not receiving sodium bicarbonate during the overall study, wk 0 to 6. Daily gain and efficiencies during wk 0 to 6 were .41 and 2.53 for calves without .36 and 3.01 with sodium bicarbonate added to colostrum diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Effects of sodium bicarbonate, magnesium oxide, and a commercial buffer mixture in early lactation cows fed hay crop silage.

Sixteen early lactation Holstein cows fed 70% concentrate: 30% hay crop silage were used to determine effects of .7% sodium bicarbonate, .7% sodium bicarbonate plus .28% magnesium oxide, or 1.8% commercial buffer mixture (total ration dry basis). This mixture contained a variety of buffers, alkalis, and other compounds known to affect milk production or composition in some circumstances. Buffers did not affect dry matter intake, milk yield, or milk composition but decreased efficiency of milk production. Ruminal fluid pH was not affected, but fecal pH and digestibilities of dry matter, organic matter, energy, acid detergent fiber, and cellulose were increased by the mixed buffers compared with sodium bicarbonate alone. Total ruminal volatile fatty acid concentration was reduced by buffers. Compared with sodium bicarbonate alone, mixed buffers increased ruminal ammonia concentration, acetate proportion, and acetate:propionate ratio and decreased proportions of propionate and butyrate. Valerate was reduced by all three buffers. Ruminal volume and liquid dilution rate were unaffected, but buffers increased total fluid outflow from the rumen. Higher amounts of buffers or alkalis may be necessary to offset low rumen pH and affect production with hay crop silage-based diets.

Animal Feed↗
PubMed1983

Dietary interaction of phosphorus with sodium from either chloride or bicarbonate affects laying hen performance.

Experimental diets consisting of two levels of total phosphorus (.30 and .75%) and three different treatments of supplemental sodium (.35% NaCl, 1.40% NaCl, and .35% NaCl plus 1.50% NaHCO3) were fed in a 2 X 3 factorial arrangement to laying hens for 16 weeks. The latter two treatments of sodium were designed to supply the same level of sodium (.55%) from different chemical forms. Hens fed .30% phosphorus laid significantly (P less than .01) less eggs than those fed .75% phosphorus. A highly significant (P less than .01) interaction was found between phosphorus and sodium treatments. The high level of sodium from either chloride or bicarbonate decreased egg production at the lower level of phosphorus and increased it when the higher level of phosphorus was fed. Sodium bicarbonate affected egg production more strongly than sodium chloride did. There were no significant treatment effects on egg weight and egg shell weight. Addition of sodium bicarbonate to the low phosphorus diet significantly (P less than .05) decreased feed consumption of the hen. Supplemental sodium bicarbonate with either level of dietary phosphorus significantly (P less than .05) increased percent nitrogen retention of the hen, but excessive sodium chloride did not.

Animals↗
PubMed1984

Interrelationship between sodium chloride, sodium bicarbonate, calcium, and phosphorus in laying hen diets.

Three experiments were conducted with Hy-Line W-36 laying hens housed in individual wire cages in open type houses. The first and second experiments were designed to investigate the effects of sodium chloride and sodium bicarbonate fed at two levels of dietary total phosphorus (.30 and .60%). The third experiment was designed to study the interrelationships between age and sodium source. Supplementing sodium chloride at two levels (.37 and 1.11%) did not effect hen performance, except that egg production was better at the lower NaCl. Egg production was greater when .60 rather than .30% dietary phosphorus was fed. Egg specific gravity and egg weight were decreased at the lower dietary phosphorus. The addition of 1.6% sodium bicarbonate in the sodium chloride-free diets was deleterious to hen performance in all experiments. High mortality was observed in both experiments in which hens were fed diets containing high sodium and low chloride. Plasma calcium and phosphorus levels were significantly depressed in hens fed diets containing the lower phosphorus. Blood pH, base excess, bicarbonate, and total carbon dioxide were significantly increased by sodium bicarbonate supplementation, and these values were found to be inversely related to dietary phosphorus levels.

Animals↗
PubMed1992

[Effects of sodium bicarbonate on the end-tidal CO2,PaCO2, HCO3-, PH and cerebral blood flow].

To estimate the quantitative reactivity of cerebral blood flow (CBF), the effects of sodium bicarbonate on the end-tidal CO2, arterial PaCO2, HCO3-, PH and CBF were examined. The CBF was measured by 133Xe inhalation method with ring type SPECT (HEADTOME). Activation study with sodium bicarbonate administration was performed after 30 minute of resting study, and the reactivity of each parameters was investigated. The arterial HCO3- and PH increased with similar reactivity, but PaCO2, end-tidal CO2 and CBF in the non-injured hemisphere changed with irregular reactivity. The excellent correlation between PaCO2 and end-tidal CO2 was vanished by the administration of sodium bicarbonate. The reactivity of CBF did not correlate with reactivity of PaCO2 and end-tidal CO2, but correlated with arterial HCO3- and PH. Thus the measurement of arterial HCO3- and PH may be indispensable to estimate the CBF reactivity with the administration of sodium bicarbonate.

Aged↗
PubMedDate not supplied

[Gastric emptying and metabolic acidosis. II. Study, in an experimental model in rats, of gastric retention of a sodium bicarbonate solution].

The gastric emptying of a 0.25 M sodium bicarbonate solution was studied in rats with metabolic acidosis induced by a previous (6 hours) orogastric infusion of a 0.5 M ammonium chloride solution. Two control groups were used: one previously infused with 0.5 M sodium chloride and the other with water, in the same volume that further solutions. Every animal was fed with 2 ml/100 g of its weight of these solutions. The test meal (bicarbonate solution) was utilized containing 6 mg% red fenol as a marker. The gastric retentions were determined 6 hours after those first meals at 5, 10, 20 and 30 minutes. The results demonstrated that the gastric retentions of the bicarbonate solution were significantly lower in the acidotic group than that one of water group (at 20 minutes) and that one of the sodium chloride (at 10, 20 and 30 minutes). The data here presented suggest that metabolic acidosis accelerates the gastric emptying of a sodium bicarbonate solution.

Acidosis↗
PubMed1991

Stability of amrinone and digoxin, procainamide hydrochloride, propranolol hydrochloride, sodium bicarbonate, potassium chloride, or verapamil hydrochloride in intravenous admixtures.

The stability of amrinone and digoxin, procainamide hydrochloride, propranolol hydrochloride, sodium bicarbonate, potassium chloride, or verapamil hydrochloride in intravenous admixtures was studied. Admixtures of amrinone and digoxin were studied at one concentration. Amrinone admixtures with propranolol hydrochloride, sodium bicarbonate, potassium chloride, and verapamil hydrochloride were studied at two concentrations. In general, 0.45% sodium chloride injection was used as the diluent; 5% dextrose injection was also used for the procainamide hydrochloride experiments. Duplicate solutions of each test admixture and single-drug control admixture were prepared and stored for four hours at 22-23 degrees C under fluorescent light. Samples were analyzed by visual inspection, tested for pH, and assayed by high-performance liquid chromatography. Admixtures containing amrinone 1.25 or 2.5 mg/mL (as the lactate salt) and sodium bicarbonate 37.5 mg/mL precipitated immediately or within 10 minutes. No changes in pH or visual appearance were noted for amrinone admixtures with procainamide hydrochloride, digoxin, propranolol hydrochloride, potassium chloride, and verapamil hydrochloride. Appreciable degradation of both amrinone and procainamide was observed after four hours when the two were mixed in 5% dextrose. No degradation of amrinone or procainamide was seen when the 5% dextrose was replaced by 0.45% sodium chloride. Amrinone and sodium bicarbonate were incompatible in intravenous admixtures. Amrinone was compatible with digoxin, propranolol hydrochloride, potassium chloride, and verapamil hydrochloride. Amrinone and procainamide were compatible in 0.45% sodium chloride injection but not in 5% dextrose injection.

Amrinone↗
PubMedDate not supplied

pH adjustment of local anesthetic solutions with sodium bicarbonate: laboratory evaluation of alkalinization and precipitation.

pH adjustment of several commonly administered local anesthetic solutions was evaluated in the laboratory. The pH achieved after the addition of sodium bicarbonate and the onset of precipitation for alkalinized solutions were recorded. Solutions of 2-chloroprocaine and lidocaine readily alkalinized to near physiological pH without precipitation. Mepivacaine solutions exhibited a tendency for delayed precipitation (18-20-minute latency for 1.5% mepivacaine) above neutral pH. Bupivacaine and etidocaine solutions precipitated after the addition of small amounts of sodium bicarbonate and could not be alkalinized to physiologic pH. Two commercially available sodium bicarbonate preparations, 4% (wt/vol) and 8.4% (wt/vol), were compared and produced similar pH changes and precipitation behavior. The data obtained for pH and time to precipitation for local anesthetic solutions alkalinized with sodium bicarbonate may be useful for practical application in the clinical setting.

Anesthetics, Local↗
PubMed1987

Sodium bicarbonate in the perinatal setting--revisited.

After more than 25 years of experience with sodium bicarbonate, the following conclusions may be in order: 1. It is not certain that the net effect of administration of this agent to patients with metabolic acidosis is positive, other than when given as replacement for renal or gastrointestinal bicarbonate losses. 2. Adequate oxygenation and ventilation must be ensured before it is given. 3. Profound fluctuations in blood pressure and cerebral blood flow, intracranial bleeds, and compromise of oxygen delivery to tissues all have been found to be possible adverse effects of sodium bicarbonate infusion. Because hyperosmolarity and sodium content are important factors, the commercially prepared solutions (0.9 or 1M) should be diluted 1:2 to 1:4 with water and given over not less than several minutes--if it is to be given at all. 4. Current recommendations for dose, dilution, and rate of administration, including those mentioned above, are largely arbitrary. If sodium bicarbonate were a newly proposed treatment for hypoxic metabolic acidosis, one would recommend that carefully conducted prospective laboratory and clinical trials be done before giving it to sick patients. As it is in widespread use, one can only reiterate that if it is to be given, it should be used with extreme caution.

Acidosis↗
PubMed1988

Effect of gentamicin sulfate and sodium bicarbonate on the synovium of clinically normal equine antebrachiocarpal joints.

The effect of gentamicin sulfate, unbuffered and buffered with sodium bicarbonate, on synovial fluid and membrane of clinically normal equine joints was evaluated. Thirty-six adult horses with clinically normal antebrachiocarpal joints were allotted to 6 treatment groups of 6 horses each. One antebrachiocarpal joint in each horse was chosen for treatment. Group-1 horses were given gentamicin (3 ml; 50 mg/ml); group-2 horses were given sodium bicarbonate (3 ml; 1 mEq/ml); group-3 horses were given gentamicin (3 ml; 50 mg/ml) and sodium bicarbonate (3 ml; 1 mEq/ml); group-4 horses were not treated; and horses of groups 5 and 6 were given polyionic physiologic solution (3 and 6 ml, respectively). Synovial fluid specimens were obtained from 5 horses of each group for cytologic analysis at postinjection hours (PIH) 0, 24, 72, and 192 and for pH determination at PIH 0, 0.25, 0.5, 1, 4, 8, 24, 72, and 192. The sixth horse of each group was euthanatized at PIH 24, and the synovial membrane of the treated and contralateral (nontreated) antebrachiocarpal joints was examined macroscopically and microscopically. After intra-articular gentamicin administration, the mean synovial fluid pH was lowest (5.98) at PIH 0.25, but by PIH 8, it was not significantly different from the control value (group-5 horses). When sodium bicarbonate was combined with gentamicin before intra-articular administration, the mean synovial fluid pH was lowest (7.07) at PIH 0.25, but by PIH 1, it was not significantly different from the control value (group-6 horses).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗