Balanced Multielectrolyte Solution versus Saline in Critically Ill Adults.

BACKGROUND: Whether the use of balanced multielectrolyte solution (BMES) in preference to 0.9% sodium chloride solution (saline) in critically ill patients reduces the risk of acute kidney injury or death is uncertain. METHODS: In a double-blind, randomized, controlled trial, we assigned critically ill patients to receive BMES (Plasma-Lyte 148) or saline as fluid therapy in the intensive care unit (ICU) for 90 days. The primary outcome was death from any cause within 90 days after randomization. Secondary outcomes were receipt of new renal-replacement therapy and the maximum increase in the creatinine level during ICU stay. RESULTS: A total of 5037 patients were recruited from 53 ICUs in Australia and New Zealand - 2515 patients were assigned to the BMES group and 2522 to the saline group. Death within 90 days after randomization occurred in 530 of 2433 patients (21.8%) in the BMES group and in 530 of 2413 patients (22.0%) in the saline group, for a difference of -0.15 percentage points (95% confidence interval [CI], -3.60 to 3.30; P = 0.90). New renal-replacement therapy was initiated in 306 of 2403 patients (12.7%) in the BMES group and in 310 of 2394 patients (12.9%) in the saline group, for a difference of -0.20 percentage points (95% CI, -2.96 to 2.56). The mean (±SD) maximum increase in serum creatinine level was 0.41±1.06 mg per deciliter (36.6±94.0 µmol per liter) in the BMES group and 0.41±1.02 mg per deciliter (36.1±90.0 µmol per liter) in the saline group, for a difference of 0.01 mg per deciliter (95% CI, -0.05 to 0.06) (0.5 µmol per liter [95% CI, -4.7 to 5.7]). The number of adverse and serious adverse events did not differ meaningfully between the groups. CONCLUSIONS: We found no evidence that the risk of death or acute kidney injury among critically ill adults in the ICU was lower with the use of BMES than with saline. (Funded by the National Health and Medical Research Council of Australia and the Health Research Council of New Zealand; PLUS ClinicalTrials.gov number, NCT02721654.).

The effects of 0.9% saline versus Plasma-Lyte 148 on renal function as assessed by creatinine concentration in patients undergoing major surgery: A single-centre double-blinded cluster crossover trial.

OBJECTIVES: Saline and Plasma-Lyte have different physiochemical contents; consequently, they may differently affect patients' renal function. We compared the effects of fluid therapy with 0.9% saline and with Plasma-Lyte 148 on renal function as assessed by creatinine concentration among patients undergoing major surgery. METHODS: We conducted a prospective, double-blinded cluster crossover trial comparing the effects of the two fluids on major surgery patients. The primary aim was to establish the pilot feasibility, safety and preliminary efficacy evidence base for a large interventional trial to establish whether saline or Plasma-Lyte is the preferred crystalloid fluid for managing major surgery patients. The primary efficacy outcome was the proportion of patients with changes in renal function as assessed by creatinine concentration during their index hospital admission. We used changes in creatinine to define acute kidney injury (AKI) according to the RIFLE criteria. RESULTS: The study was feasible with 100% patient and clinician acceptance. There were no deviations from the trial protocol. After screening, we allocated 602 patients to saline and 458 to Plasma-Lyte. The median (IQR) volume of intraoperative fluid received was 2000 mL (1000:2000) in both groups. Forty-nine saline patients (8.1%) and 49 Plasma-Lyte patients (10.7%) developed a postoperative AKI (adjusted incidence rate ratio [aIRR]: 1.34; 95% CI: 0.93-1.95; p = 0.120). No differences were observed in the development of postoperative complications (aIRR: 0.98; 95% CI: 0.89-1.08) or the severity of the worst complication (aIRR: 1.00; 95% CI: 0.78-1.30). The median (IQR) length of hospital stay was six days (3:11) for the saline group and five days (3:10) for the Plasma-Lyte group (aIRR: 0.85; 95% CI: 0.73-0.98). There were no serious adverse events relating to the trial fluids, nor were there fluid crossover or contamination events. CONCLUSIONS: The study design was feasible to support a future follow-up larger clinical trial. Patients treated with saline did not demonstrate an increased incidence of postoperative AKI (defined as changes in creatinine) compared to those treated with Plasma-Lyte. Our findings imply that clinicians can reasonably use either solution intraoperatively for adult patients undergoing major surgery. TRIAL REGISTRATION: Registry: Australian New Zealand Clinical Trials Registry; ACTRN12613001042730; URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364988.

Low-chloride versus high-chloride hypertonic solution for the treatment of subarachnoid hemorrhage-related complications (The ACETatE trial): study protocol for a pilot randomized controlled trial.

BACKGROUND: Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening condition that results from a ruptured cerebral vessel. Cerebral edema and vasospasm are common complications and frequently require treatment with hypertonic solutions, in particular hypertonic sodium chloride (NaCl). We have previously shown that hyperchloremia in patients with aSAH given hypertonic NaCl is associated with the development of acute kidney injury (AKI), which leads to higher morbidity and mortality. Our current trial aims to study the effect of two hypertonic solutions with different chloride content on serum chloride concentrations in patients with aSAH who are at risk for AKI. METHODS: A low ChloridE hyperTonic solution for brain Edema (ACETatE) is a single center, double-blinded, double-dummy pilot trial comparing bolus doses of 23.4% NaCl and 16.4% NaCl/Na-Acetate for the treatment of cerebral edema in patients with aSAH. All patients will be enrolled within 36 h following admission. Randomization will occur once patients who receive hypertonic treatment for cerebral edema develop hyperchloremia (serum Cl- concentration ≥ 109 mmol/L). Subsequent treatment will consist of either NaCl 23.4% or NaCl/Na-Acetate 16.4%. The primary outcome of this study will be the change in serum Cl- concentrations during treatment. Secondary outcomes will include incidence of AKI, mortality, changes in intracranial pressure, and extent of hypernatremia. DISCUSSION: In patients with aSAH, hyperchloremia is a known risk factor for subsequent development of AKI. The primary goal of this pilot study is to determine the effect of two hypertonic solutions with different Cl- content on serum Cl- concentrations in patients with aSAH who have already developed hyperchloremia. Data will be collected prospectively to determine the extent to which the choice of hypertonic saline solution affects subsequent serum Cl- concentrations and the occurrence of AKI. This approach will allow us to obtain preliminary data to design a large randomized trial assessing the effects of chloride-sparing hypertonic solutions on development of AKI in patients with SAH. This pilot study is the first to prospectively evaluate the relationship between hypertonic solution chloride content and its effect on serum electrolytes and renal function in aSAH patients at risk of AKI due to hyperchloremia. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03204955 . Registered on 28 June 2017.

The effects of Plasma-Lyte 148 solution on blood coagulation: an in-vitro, volunteer study using rotational thromboelastometry.

: The current study aimed to measure the effects of Plasma-Lyte 148 solution on the blood coagulation profile according to the hemodilution level using rotational thromboelastometry (ROTEM) tests. Venous blood was collected from 12 healthy volunteers and divided into four specimen bottles, which were diluted at different levels with Plasma-Lyte 148 (0, 20, 40, and 60%). Following this, ROTEM tests were performed on the study samples. We found that as the hemodilution level increased, the ROTEM values showed a hypocoagulable pattern. The change rate of the maximum clot firmness (MCF) of INTEM was greater in the 40 (P = 0.015) and 60% (P < 0.001) dilutions than it was in the 20% dilution. Greater lengthening of the clot formation time of EXTEM was observed in the 60% dilution than it was in the 20% dilution (P < 0.001). The alpha-angle of EXTEM showed a greater decrease in the 60% dilution than it did in the 20% dilution (P < 0.001). A larger change rate of the MCF of EXTEM was observed in the 40 (P = 0.003) and 60% (P < 0.001) dilutions than it was in the 20% dilution. A greater decrease in the MCF of FIBTEM was identified in the 40 (P = 0.009) and 60% (P < 0.001) dilutions than in the 20% dilution. All coagulation pathways exhibited hypocoagulable patterns as the hemodilution level increased. However, most of the mean values of ROTEM parameters were within the normal reference range, except for those of the 60% dilution.

Comparison of enteral and parenteral methods of urine alkalinization in patients receiving high-dose methotrexate.

Purpose Hyperhydration and urinary alkalinization is implemented with all high-dose (HD)-methotrexate infusions to promote excretion and prevent precipitation of methotrexate in the renal tubules. Our institution utilized enteral alkalinizing agents (sodium bicarbonate tablets and sodium citrate/citric acid solution) to alkalinize the urine of patients receiving HD-methotrexate during a parenteral sodium bicarbonate and sodium acetate shortage. The purpose of this study is to establish the safety and efficacy of the enteral route for urine alkalinization. Methods A single-center, retrospective, cohort study was conducted comparing cycles of HD-methotrexate using enteral alkalinizing agents to parenteral sodium bicarbonate. The primary objective was to compare the time, in hours, from administration of first inpatient administered dose of alkalinizing agent to time of achieving goal urine pH. Secondary objectives evaluated total dose of sodium bicarbonate required to achieve goal urine pH, time from start of urine alkalinizing agent until time of achieving methotrexate level safe for discharge, and toxicities associated with methotrexate and the alkalinizing agents. Results A total of 118 patients were included in this study, equally divided into two cohorts based on parenteral versus enteral routes of administration. No statistical difference was determined between the two cohorts regarding time to goal urine pH (6.5 h versus 7.9 h, P = 0.051) or regarding time to methotrexate level deemed safe for discharge (63.5 h versus 62.5 h, p = 0.835). There were no significant differences in methotrexate-induced toxicities. Conclusion Our study found enteral routes of urine alkalinization to be a viable alternative to the traditional parenteral sodium bicarbonate, especially during parenteral sodium bicarbonate and acetate shortages.

Sodium acetate as a replacement for sodium bicarbonate in medical toxicology: a review.

Sodium bicarbonate is central to the treatment of many poisonings. When it was placed on the FDA drug shortage list in 2012, alternative treatment strategies to specific poisonings were considered. Many hospital pharmacies, poison centers, and medical toxicologists proposed sodium acetate as an adequate alternative, despite a paucity of data to support its use in medical toxicology. The intention of this review is to educate the clinician on the use of sodium acetate and to advise them on the potential adverse events when given in excess. We conducted a literature search focused on the pharmacology of sodium acetate, its use as a buffer in pathologic acidemia and dialysis baths, and potential adverse events associated with excess sodium acetate infusion. It appears safe to replace sodium bicarbonate infusion with sodium acetate on an equimolar basis. The metabolism of acetate, however, is more complex than bicarbonate. Future prospective studies will be needed to confirm the efficacy of sodium acetate in the treatment of the poisoned patient.

Cognitive changes after saline or plasmalyte infusion in healthy volunteers: a multiple blinded, randomized, cross-over trial.

BACKGROUND: In an incidental finding, during a study of plasma chemistry after crystalloid infusion, participants reported subjective cognitive changes, particularly slower thinking, after saline but not Hartmann's (Ringer's lactate) solution. The authors tested the hypothesis that saline infusion would produce greater adverse cognitive changes than Plasmalyte infusion. METHODS: The authors conducted a randomized, cross-over, multiple blinded study of healthy adult volunteers. On separate days, participants received 30 ml/kg over 1 h of either 0.9% saline or Plasmalyte with the order randomly allocated. Plasma chemistry was tested on venous samples. As part of a battery of cognitive tests our primary endpoint was the reaction time index after infusion. RESULTS: The authors studied 25 participants. Plasma chloride was greater after saline than after Plasmalyte: mean difference 5.4 mM (95% CI, 4.1-6.6 mM; P < 0.001). Saline was also associated with greater metabolic acidosis: base-excess 2.5 mM more negative (95% CI, 1.9-3.0 mM more negative; P < 0.001). There was no evidence of a difference in the reaction time index between the two interventions: mean reaction time index 394 ms (SD, 72) after saline versus 385 ms (SD, 55) after Plasmalyte. Difference: saline 9 ms slower (95% CI, 30 ms slower to 12 ms faster; P = 0.39). There were minimal differences in the other cognitive and mood tests. CONCLUSIONS: Despite expected differences in plasma chemistry, the authors found that measures of cognition did not differ after infusions of Plasmalyte or saline.

Major complications, mortality, and resource utilization after open abdominal surgery: 0.9% saline compared to Plasma-Lyte.

OBJECTIVE: To assess the association of 0.9% saline use versus a calcium-free physiologically balanced crystalloid solution with major morbidity and clinical resource use after abdominal surgery. BACKGROUND: 0.9% saline, which results in a hyperchloremic acidosis after infusion, is frequently used to replace volume losses after major surgery. METHODS: An observational study using the Premier Perspective Comparative Database was performed to evaluate adult patients undergoing major open abdominal surgery who received either 0.9% saline (30,994 patients) or a balanced crystalloid solution (926 patients) on the day of surgery. The primary outcome was major morbidity and secondary outcomes included minor complications and acidosis-related interventions. Outcomes were evaluated using multivariable logistic regression and propensity scoring models. RESULTS: For the entire cohort, the in-hospital mortality was 5.6% in the saline group and 2.9% in the balanced group (P < 0.001). One or more major complications occurred in 33.7% of the saline group and 23% of the balanced group (P < 0.001). In the 3:1 propensity-matched sample, treatment with balanced fluid was associated with fewer complications (odds ratio 0.79; 95% confidence interval 0.66-0.97). Postoperative infection (P = 0.006), renal failure requiring dialysis (P < 0.001), blood transfusion (P < 0.001), electrolyte disturbance (P = 0.046), acidosis investigation (P < 0.001), and intervention (P = 0.02) were all more frequent in patients receiving 0.9% saline. CONCLUSIONS: Among hospitals in the Premier Perspective Database, the use of a calcium-free balanced crystalloid for replacement of fluid losses on the day of major surgery was associated with less postoperative morbidity than 0.9% saline.

Plasma-Lyte 148 vs 0.9% saline for fluid resuscitation in diabetic ketoacidosis.

PURPOSE: The purpose of the study was to determine the effects of Plasma-Lyte 148 (PL) vs 0.9% saline (NS) fluid resuscitation in diabetic ketoacidosis (DKA). METHODS: A multicenter retrospective analysis of adults admitted for DKA to the intensive care unit, who received almost exclusively PL or NS infusion up until 12 hours, was performed. RESULTS: Nine patients with PL and 14 patients with NS were studied. Median serum bicarbonate correction was higher in the PL vs NS groups at 4 to 6 hours (8.4 vs 1.7 mEq/L) and 6 to 12 hours (12.8 vs 6.2 mEq/L) from baseline (P < .05). Median standard base excess improved by 10.5 vs 4.2 mEq/L at 4 to 6 hours and by 16.0 vs 9.1 mEq/L at 6 to 12 hours in the PL and NS groups, respectively (P < .05). Chloride levels increased significantly in the NS vs PL groups over 24 hours. Potassium levels were lower at 6 to 12 hours in the PL group. Mean arterial blood pressure was higher at 2 to 4 hours in the PL group, whereas cumulative urine output was lower at 4 to 6 hours in the NS group. There were no differences in glycemic control or duration of intensive care unit stay. CONCLUSION: Patients with DKA resuscitated with PL instead of NS had faster initial resolution of metabolic acidosis and less hyperchloremia, with a transiently improved blood pressure profile and urine output.

Anxiogenic and stress-inducing effects of peripherally administered acetaldehyde in mice: similarities with the disulfiram-ethanol reaction.

UNLABELLED: Peripheral accumulation of acetaldehyde, the first metabolite of ethanol, produces autonomic responses in humans called "flushing". The aversive characteristics of flushing observed in some populations with an isoform of aldehyde dehydrogenase (ALDH2) less active, are the basis for treating alcoholics with disulfiram, an ALDH inhibitor. Although ethanol and centrally formed acetaldehyde have anxiolytic effects, peripheral accumulation of acetaldehyde may be aversive in part because it is anxiogenic. OBJECTIVES: We investigated the effect of direct administration of acetaldehyde on behavioral measures of anxiety and on hormonal markers of stress in mice. The impact of disulfiram on the anxiolytic actions of ethanol was evaluated. Acetate (a metabolite of acetaldehyde) was also studied. METHODS: CD1 male mice received acetaldehyde (0, 25, 50, 75 or 100 mg/kg) at different time intervals and were assessed in the elevated plus maze and in the dark-light box. Corticosterone release after acetaldehyde administration was also assessed. Additional experiments evaluated the impact of disulfiram on the anxiolytic effect of ethanol (0 or 1 mg/kg), and the effect of acetate on the plus maze. RESULTS: Direct administration of acetaldehyde (100 mg/kg) had an anxiogenic effect at 1, 11 or 26 min after IP administration. Acetaldehyde was ten times more potent than ethanol at inducing corticosterone release. Disulfiram did not affect behavior on its own, but blocked the anxiolytic effect of ethanol at doses of 30 and 60 mg/kg, and had an anxiogenic effect at the highest dose (90 mg/kg) when co-administered with ethanol. Acetate did not affect any of the anxiety parameters. CONCLUSIONS: Peripheral administration or accumulation of acetaldehyde produces anxiogenic effects and induces endocrine stress responses. This effect is not mediated by its metabolite acetate.

Lactic acidosis after resuscitation with sodium acetate.

BACKGROUND: At our institution, we began using sodium acetate for resuscitation of trauma patients in 2005. Sodium acetate is used as an alternative to normal saline to help prevent hyperchloremic metabolic acidosis as well as to help buffer metabolic acidosis. DISCUSSION: Here we present a case of a 29-year-old trauma patient who began to have severe lactic acidosis after the infusion of sodium acetate. This is the first reported case of lactic acidosis caused by sodium acetate infusion. Up to this point, we have not experienced any adverse events and patients have tolerated sodium acetate well. CONCLUSION: This unique case report presents the first case of lactic acidosis from sodium acetate infusion. The lactic acidosis seen in this patient reminds us of the complex regulation of pyruvate dehydrogenase and the potential for down regulation of the enzyme shunting substrates to formation of lactate.

Impact of Plasma-Lyte pH 7.4 on acid-base status and hemodynamics in a model of controlled hemorrhagic shock.

OBJECTIVE: Intravenous infusion of crystalloid solutions is a cornerstone of the treatment of hemorrhagic shock. However, crystalloid solutions can have variable metabolic acid-base effects, perpetuating or even aggravating shock-induced metabolic acidosis. The aim of this study was to compare, in a controlled volume-driven porcine model of hemorrhagic shock, the effects of three different crystalloid solutions on the hemodynamics and acid-base balance. METHODS: Controlled hemorrhagic shock (40% of the total blood volume was removed) was induced in 18 animals, which were then treated with normal saline (0.9% NaCl), Lactated Ringer's Solution or Plasma-Lyte pH 7.4, in a blinded fashion (n = 6 for each group). Using a predefined protocol, the animals received three times the volume of blood removed. RESULTS: The three different crystalloid infusions were equally capable of reversing the hemorrhage-induced low cardiac output and anuria. The Lactated Ringer's Solution and Plasma-Lyte pH 7.4 infusions resulted in an increased standard base excess and a decreased serum chloride level, whereas treatment with normal saline resulted in a decreased standard base excess and an increased serum chloride level. The Plasma-Lyte pH 7.4 infusions did not change the level of the unmeasured anions. CONCLUSION: Although the three tested crystalloid solutions were equally able to attenuate the hemodynamic and tissue perfusion disturbances, only the normal saline induced hyperchloremia and metabolic acidosis.

Impact of Plasma-Lyte pH 7.4 on acid-base status and hemodynamics in a model of controlled hemorrhagic shock

OBJECTIVE: Intravenous infusion of crystalloid solutions is a cornerstone of the treatment of hemorrhagic shock. However, crystalloid solutions can have variable metabolic acid-base effects, perpetuating or even aggravating shock-induced metabolic acidosis. The aim of this study was to compare, in a controlled volume-driven porcine model of hemorrhagic shock, the effects of three different crystalloid solutions on the hemodynamics and acid-base balance. METHODS: Controlled hemorrhagic shock (40 percent of the total blood volume was removed) was induced in 18 animals, which were then treated with normal saline (0.9 percent NaCl), Lactated Ringer's Solution or Plasma-Lyte pH 7.4, in a blinded fashion (n = 6 for each group). Using a predefined protocol, the animals received three times the volume of blood removed. RESULTS: The three different crystalloid infusions were equally capable of reversing the hemorrhage-induced low cardiac output and anuria. The Lactated Ringer's Solution and Plasma-Lyte pH 7.4 infusions resulted in an increased standard base excess and a decreased serum chloride level, whereas treatment with normal saline resulted in a decreased standard base excess and an increased serum chloride level. The Plasma-Lyte pH 7.4 infusions did not change the level of the unmeasured anions. CONCLUSION: Although the three tested crystalloid solutions were equally able to attenuate the hemodynamic and tissue perfusion disturbances, only the normal saline induced hyperchloremia and metabolic acidosis.

[Can modern infusion solutions cause serious disruption of inner environment of an organism?]. / Mohou moderní infuzní roztoky zpusobit závazný rozvrat vnitrního prostredí organizmu?

The article brings a description of a patient case when an application of mineral balanced infusion solutions led to a disruption of inner environment, beginning of a combined failure of the acid-base balance with a serious metabolic acidosis. Patient J. was artificially respirated after a CPR. During the therapy the patient was given basically without any changes a combination of mineral solution Plasma-Lyte 148, amino-acid and 20% glucose. During 8 days a serious metabolic alkalosis had developed (caused by a lack of chlorides, phosphates and other reasons), combined with respirational acidosis. Hydrogencarbonate level was increased to 47.2 mmo/l (at norm of 24 mmol/l), base excess level to 21.4 mmol/l (at norm of 0 mmol/l). Metabolic acidosis led to reduction of sensibility of the respiratory centers and therefore it was not possible to restore spontaneous respiration. After the therapy change and reduction of metabolic acidosis the state of the patient got better. Application of acidifying solutions, supplementation of phosphate and potassium levels and replenishment of actual losses of phosphates led to regulation of the inner environment. Together with the application of sufficient amount of basic nutrients was the improvement of acid-base balance the key factor which enabled the restoration of spontaneous respiration and disconnection of the patient from the ventilator. In short summary you can see reasons which cause different effect of identical infusions to acid-base balance of the inmates in different situations. The article points to a necessity of controlling groovy medical procedures according to actual patient's needs.

Sodium acetate induces a metabolic alkalosis but not the increase in fatty acid oxidation observed following bicarbonate ingestion in humans.

We conducted this study to quantify the oxidation of exogenous acetate and to determine the effect of increased acetate availability upon fat and carbohydrate utilization in humans at rest. Eight healthy volunteers (6 males and 2 females) completed 2 separate trials, 7 d apart in a single-blind, randomized, crossover design. On each occasion, respiratory gas and arterialized venous blood samples were taken before and during 180 min following consumption of a drink containing either sodium acetate (NaAc) or NaHCO3 at a dose of 2 mmol/kg body mass. Labeled [1,2 -13C] NaAc was added to the NaAc drink to quantify acetate oxidation. Both sodium salts induced a mild metabolic alkalosis and increased energy expenditure (P < 0.05) to a similar magnitude. NaHCO3 ingestion increased fat utilization from 587 +/- 83 kJ/180 min to 693 +/- 101 kJ/180 min (P = 0.01) with no change in carbohydrate utilization. Following ingestion of NaAc, the amount of fat and carbohydrate utilized did not differ from the preingestion values. However, oxidation of the exogenous acetate almost entirely (90%) replaced the additional fat that had been oxidized during the bicarbonate trial. We determined that 80.1 +/- 2.3% of an exogenous source of acetate is oxidized in humans at rest. Whereas NaHCO3 ingestion increased fat oxidation, a similar response did not occur following NaAc ingestion despite the fact both sodium salts induced a similar increase in energy expenditure and shift in acid-base balance.

Effects of various arterial infusion solutions on red blood cells in the newborn.

AIM: To examine in vitro the effects of brief contact with various infusion solutions on red blood cells from newborn infants, as occurs in the "waste" syringe during routine blood sampling from umbilical artery catheters. The mixture of blood and solution in the "waste" syringe is usually reinfused into the baby. Reinfused red blood cells may be damaged by the infusion solution. It is hypothesised that an isotonic amino acid solution would cause no red blood cell agglutination and no more haemolysis than many commonly used solutions. METHODS: Blood was obtained from the placentas of 15 normal term babies. Haemolysis was estimated by measuring plasma (free) haemoglobin after mock blood sampling. Agglutination was measured semiquantitatively by direct observation. RESULTS: A 0.25% normal saline solution caused 5.4% haemolysis, significantly more than all the other fluids tested. There was less haemolysis with 0. 25% normal saline when there was complete mixing of blood and solution within the "waste" syringe. Normal saline and isotonic sodium acetate solutions caused < 0.1% haemolysis, significantly less than all the other fluids tested. The isotonic amino acid solution caused 0.8% haemolysis, which is similar to that caused by the remaining solutions tested. Agglutination was seen with isotonic dextrose and with the two isotonic amino acid solutions containing cysteine. CONCLUSIONS: Isotonic amino acid solution (without added cysteine) caused no agglutination and the same or less haemolysis than many commonly used solutions and may offer advantages in nutrition and fluid balance.

Effects of sodium acetate on rat bone-nodule formation and mineralization in vitro.

Sodium acetate reportedly promotes bone atrophy by inducing resorption and inhibiting osteoprogenitor-cell proliferation, but little is known about its effects on bone-matrix deposition and mineralization by a population containing osteoprogenitor cells. The objective here was to assess the effects of 1-20 mM sodium acetate on the proliferation and differentiation of these cells and their resultant bone-nodule formation and mineralization in an in vitro assay. Exposure to 10 mM sodium acetate had no effect on cellular proliferation but significantly increased the production and mineralization of bone nodules (p < 0.01), suggesting that it affected osteoprogenitor differentiation and subsequent metabolism. However, 10 mM acetate did not increase net bone mass. Dilutions of 1-5 and 20 mM inhibited cellular proliferation and resultant bone-nodule formation and mineralization, significantly reducing the percentage bone area as compared to controls (p < 0.001). These data suggest that 1-5 and 20 mM sodium acetate significantly inhibit bone deposition, whereas 10 mM has no effects, which could contribute to iatrogenic metabolic bone disease in patients receiving either renal dialysis or total parenteral nutrition.

Anaphylactoid reaction to maltose 5% solution during spinal anaesthesia.

PURPOSE: A rare case of an anaphylactoid reaction to maltose solution is presented. CLINICAL FEATURES: A 28-yr-old man underwent repair of bilateral inguinal hernia under spinal anaesthesia with dibucaine. At the end of operation, he developed generalized flush and circulatory collapse immediately after receiving Na acetate solution containing maltose, 5%, i.v. The reactions were treated with 32 mg ephedrine and 250 mg methylprednisolone i.v., and rapid infusion of 1,000 ml acetated Ringer's solution. The skin tests provoked positive responses to maltose solutions. CONCLUSION: The clinical features and skin tests suggested that the episode was an anaphylactoid reaction to maltose. Maltose is one of the dissacharides (MW: 342) produced from starch and glycogen. Maltose solutions are used frequently in Japan as a carbohydrate source. Further study is required to confirm whether maltose has an immunological antigen-eliciting activity.