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.).

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.

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.

[Can modern infusion solutions cause serious disruption of inner environment of an organism?]

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.

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.

Cardiopulmonary bypass tubes and prime solutions stimulate neutrophil adhesion molecules

OBJECTIVE

To evaluate effects of the material of the cardiopulmonary bypass (CPB) tubes (polyvinyl chloride, PVC) and prime solutions on expression of neutrophil adhesion molecule CD11b and L-selectin.

METHODS

We carried out a series of experiments using donor blood from 30 healthy adult human volunteers. In all experiments, neutrophil cell surface expressions of CD11b and L-selectin were assayed immediately and serially up to 2 hours, using immune-fluorescence techniques and flow cytometry. Study 1: Effects of PVC were compared with glass and polystyrene (n = 5). Study 2: Blood was mixed with Plasma-lyte (Pl) (prime solution), Hartman solutions, albumin or not altered (control), n = 5. Study 3: The effects of changing pH of the Pl (control, neutralised and acidic solution, n = 5) were examined. Study 4: Haemodilution (undiluted, 1:1, 1:2, and 1:3, vol/vol, prime to blood, n = 5) was carried out using Pl and the subsequent changes in expressions of the adhesion molecules were analysed. Study 5: The combined effect of PVC and Pl was assessed (n = 5). Study 6: We evaluated the effect of increasing plasma water by adding sterile water to whole blood and compared it with control (n = 5).

RESULTS

Study 1: PVC, similar to glass, caused more up-regulation of CD11b and down-regulation of L-selectin than polystyrene (238 and 162% vs. 68 increase of CD11b, P < 0.001; 89 and 95% vs. 16% decrease of L-selectin, P < 0.001). Study 2: Pl and Hartman solutions caused more up-regulation of CD11b and down-regulation of L-selectin compared to albumin and control (166 and 188% vs. 26 and 44% increase of CD11b, P < 0.01; 19 and 26% vs. 10 and 6% decrease of L-selectin, P < 0.01, respectively). Study 3: Haemodilution had no effect on these molecules. Study 4: The mean of the difference between the acidic and neutral solution was 208% increase of CD11b and 30% decrease of L-selectin, P < 0.05. Study 5: The combined effect of mixing blood with Pl and exposure to PVC caused marked up-regulation of CD11b (336% increase, P < 0.01) and down-regulation of L-selectin (78% decrease, P < 0.05). Study 6: Water for injection caused marked up-regulation of CD1 1b and down-regulation of L-selectin.

CONCLUSIONS

Mixing blood with acidic prime solution and/or exposing it to PVC tubes causes up-regulation of neutrophil adhesion molecule CD11b and down-regulation of L-selectin. Neutralisation of the prime solution reduces the extent of neutrophil activation, whereas haemodilution has no effect. Increasing plasma water is stimulating to the neutrophil. Modulation of prime solutions and the material of CPB tubes may reduce neutrophil activation which may reduce patient morbidity.