Saline versus Lactated Ringer’s Solution

Effect of Lactated Ringer Administration on Survival Outcomes in Critically Ill Patients With Acute Kidney Injury: A Retrospective Cohort Study

Background: Although lactated Ringer's (LR) solution is widely used in managing patients with acute kidney injury (AKI), its specific impact on mortality remains unclear. This retrospective cohort study aimed to evaluate the effects of LR administration on survival outcomes in severely ill patients with AKI. Methods: Critically ill patients with AKI were identified using data from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. Propensity score matching (PSM) was employed to address baseline discrepancies between patients who received LR and those who did not. The association of LR administration with survival, duration of hospitalization and intensive care unit (ICU) stay, requirement for renal replacement therapy (RRT), renal function recovery, and hyperkalemia was analyzed using restricted mean survival time (RMST), logistic regression, and linear regression models. Results: A total of 5620 patients with AKI were included. Following PSM, LR administration was associated with prolonged survival at 28 and 90 days compared to non-LR use (28-day survival increase: 1.12 days, 95% confidence interval [CI] 0.62-1.63, p < 0.001; 90-day survival increase: 3.73 days, 95% CI 1.70-5.76, p < 0.001). The survival benefit became more pronounced, with higher LR use linked to more remarkable 90-day survival. However, LR administration did not significantly affect renal function recovery or hyperkalemia incidence. Conclusion: Administering LR to critically ill patients with AKI was associated with improved survival at both 28 and 90 days.

Crystalloids versus Colloids: Same Controversy, New Information

Intravenous fluid therapy is a regular component of care for cats and dogs with goals of restoring tissue perfusion, preventing organ dysfunction, and maintaining homeostasis. Veterinarians have a plethora of fluid choices, including hypertonic, hypotonic, and isotonic crystalloids, as well as synthetic and natural colloids. Studies published in both the human and veterinary medical literature have documented adverse events associated with synthetic and natural colloids. Reports of increased incidences of acute kidney injury, need for renal replacement therapy, and mortality in a variety of patient populations have called into question the use of synthetic colloids in humans and companion animals.

Volume of intraoperative normal saline versus lactated Ringer's solution on acute kidney injury: A secondary analysis of the SOLAR trial

Postoperative acute kidney injury (AKI) is common after non-cardiac surgery. Normal saline and lactated Ringer's solution are both used for volume replacement during surgery. Normal saline decreases renal blood flow and causes hyperchloremic acidosis whereas lactated Ringer's does not. The incidence of AKI is similar with modest volumes of each fluid. But it remains unclear whether larger volumes of normal saline provoke AKI.

OBJECTIVE

Evaluate whether intraoperative crystalloid volume modifies the relationship between the AKI risk and treatment group.

DESIGN

Secondary analysis of a single-center multiple cross-over cluster trial.

SETTING

Intraoperative care.

PATIENTS

We enrolled 8616 adults who had colorectal or orthopedic surgery at a large academic institution.

INTERVENTIONS

Clusters of patients were alternately assigned to intraoperative normal saline or lactated Ringer's solution.

MEASUREMENTS

The primary outcome was the incidence of acute kidney injury (AKI) as a function of intraoperative crystalloid volume (0-1, 1-2, 3-4, or 4+ liters) and the type of crystalloid. Our secondary outcome was the change in postoperative serum chloride concentration during the first 24 h.

MAIN RESULTS

The risk of AKI did not differ significantly in patients given 0-1, 1-2, or 3-4 L saline or lactated Ringers solutions. In contrast, patients given 2-3 or > 4 L of lactated Ringer's solution had a higher risk of AKI than those given saline. Patients assigned to normal saline had progressively greater plasma chloride concentrations than those given lactated Ringer's across all volume categories.

CONCLUSIONS

While saline administration clearly causes volume-dependent hyperchloremia, we found no evidence to support the theory that large volumes of saline provoke AKI. Therefore, either fluid seems reasonable for intraoperative use.

Selection of intraoperative fluid for kidney transplantation

The kidney, the most frequently transplanted organ, represents the optimal treatment for end-stage renal disease. Transplanted kidneys are highly vulnerable to perioperative injuries such as hypotension and hypovolemia, which can be influenced by perioperative fluid management. Postoperatively, delayed graft function increases the risk of graft failure. Although adequate volume administration can reduce delayed graft function, the type of intraoperative fluid most likely to benefit and support graft function remains unclear. Traditionally, crystalloids have been the primary choice for fluid management during kidney transplantation. Among these, 0.9% sodium chloride is the most commonly used, as its potassium-free composition minimizes the risk of hyperkalemia in patients with end-stage renal disease. Albumin is not routinely used, whereas synthetic colloids are discouraged owing to their nephrotoxicity. To date, 0.9% sodium chloride has demonstrated fewer advantages compared with balanced crystalloids, particularly regarding acid-base homeostasis, electrolyte balance, and delayed graft function. This review aims to examine the existing evidence on the effect of crystalloids and colloids on postoperative graft function and to recommend an appropriate fluid regimen, including balanced crystalloids, for kidney transplantation.

Perioperative Acute Kidney Injury: Diagnosis, Prediction, Prevention, and Treatment

In this review, the authors define acute kidney injury in the perioperative setting, describe the epidemiologic burden, discuss procedure-specific risk factors, detail principles of management, and highlight areas of ongoing controversy and research.

Perioperative fluid management: evidence-based consensus recommendations from the international multidisciplinary PeriOperative Quality Initiative

Fluid therapy is an integral component of perioperative management. In light of emerging evidence in this area, the Perioperative Quality Initiative (POQI) convened an international multiprofessional expert meeting to generate evidence-based consensus recommendations for fluid management in patients undergoing surgery. This article provides a summary of the recommendations for perioperative fluid management of surgical patients from the preoperative period until hospital discharge and for all types of elective and emergency surgery, apart from burn injuries and head and neck surgery. Where evidence was lacking, recommendations for future research were generated. Specific recommendations are made for fluid management in elective major noncardiac surgery, cardiopulmonary bypass, thoracic surgery, neurosurgery, minor noncardiac surgery under general anaesthesia, and critical illness. There are ongoing gaps in knowledge resulting in variation in practice and some disagreement with our consensus recommendations. Perioperative fluid management should be individualised, taking into account the type of surgery and important patient factors, including intravascular volume status and acute and chronic comorbidities. Recommendations are made for further research in perioperative fluid management to address important gaps.

Use of fluid therapy in perioperative adult patients: A narrative review

The administration of intravenous fluids is the most common intervention in hospitalised patients in the perioperative setting and critical care units. The aim of this narrative review is to provide an overview of balanced solutions for fluid therapy in the perioperative period in adult patients, and to review new trends and solutions in fluid therapy. The evidence was grouped into 3 areas: intraoperative fluid administration, fluid administration in critically ill patients, and the importance / benefit of balanced crystalloid solutions. Although a number of high-quality studies have been published in recent years, the scientific evidence regarding the type of fluid, the dose, and rate of administration is still limited. The choice of fluid therapy during the perioperative period must be tailored to patient-specific factors, the nature of the surgery, expected fluid loss, and other relevant factors. Finally, more robust clinical evidence and physician training is of the utmost importance.

Quantification of Metabolic Acidosis at Bedside by S.A.L.T Approach

Introduction

Traditionally, metabolic acidosis is analyzed using an anion gap (AG). The aim of the study was to compare the utility of quantitative David Story's simplified Stewart approach against traditional approach to analyze metabolic acidosis. ICU setting. Analytical, cross-sectional observational study.

Methods

Blood gas reports of 50 adult critically ill patients with primary metabolic acidosis at admission were analyzed using both approaches. With traditional approach, acidosis was classified simply as high or normal AG acidosis. With S.A.L.T approach, the components of base deficit were further quantified into sodium chloride, albumin, lactate, and other ions effects. A contribution of sodium chloride or albumin effect of > 30% to the base deficit was considered significant. The proportion of patients with such abnormalities was determined. Descriptive statistics was used.

Results

The mean ± standard deviation (SD) age of patients was 54.52 ± 19.71 years, 52% were males, and 72% were medical admissions. The median (interquartile range [IQR]) Sequential Organ Failure Assessment score was 10 (5-13). The mean ± SD pH, bicarbonate, base excess, and albumin were 7.198 ± 0.13, 11.73 ± 4.2 mmol/L, -15.13 ± 5.6 mmol/L, and 2.9 ± 0.77 g%, respectively. The median (IQR) of serum lactate was 6.77 (1.53, 16.32) mmol/L. Hyponatremia and hypochloremia were seen in 68% and 46% of patients, respectively. Eighty-eight percent of patients had acidosis due to other ions, 52% due to lactates. Twenty-eight percent had a significant sodium chloride effect and 32% had significant hypoalbuminemia.

Conclusion

Quantification of base deficit of metabolic acidosis using S.A.L.T approach showed changes in sodium chloride levels and hypoalbuminemia affecting base deficit in nearly 30% of the patients. Quantification of metabolic acidosis using S.A.L.T approach is likely to help treat metabolic acidosis more appropriately, with clinical implications.

Effects of Balanced Versus Saline-based Solutions on Acute Kidney Injury in Off-pump Coronary Artery Bypass Surgery: A Randomized Controlled Trial

OBJECTIVES

To determine whether balanced solutions can reduce the incidence of acute kidney injury after off-pump coronary artery bypass surgery compared with saline.

DESIGN

Randomized controlled trial.

SETTING

Single tertiary care center.

PARTICIPANTS

Patients who underwent off-pump coronary artery bypass surgery between June 2014 and July 2020.

INTERVENTIONS

Balanced solution-based chloride-restrictive intravenous fluid strategy.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was acute kidney injury within 7 postoperative days, as defined by the 2012 Kidney Disease: Improving Global Outcomes Clinical Practice Guideline. The incidence of acute kidney injury was 4.4% (8/180) in the balanced group and 7.3% (13/178) in the saline group. The difference was not statistically significant (risk difference, -2.86%; 95% confidence interval [CI], -7.72% to 2.01%; risk ratio, 0.61, 95% CI, 0.26 to 1.43; p = 0.35). Compared with the balanced group, the saline group had higher levels of intraoperative serum chloride and lower base excess, which resulted in a lower pH.

CONCLUSIONS

In patients undergoing off-pump bypass surgery with a normal estimated glomerular filtration rate, the intraoperative balanced solution-based chloride-restrictive intravenous fluid administration strategy did not decrease the rate of postoperative acute kidney injury compared with the saline-based chloride-liberal intravenous fluid administration strategy.

Intraoperative Normal Saline Administration and Acute Kidney Injury in Patients Undergoing Liver Transplantation

BACKGROUND

Normal saline is still used in patients undergoing living donor liver transplantation (LDLT) with normonatremia. We investigated whether the normal saline administered during LDLT is associated with the increased risk of acute kidney injury (AKI) compared with the balanced crystalloids.

METHODS

We reviewed 1011 cases undergoing LDLT. The primary exposure variable was normal saline administered intraoperatively compared with the balanced crystalloid. To compare the risk of AKI after adjusting for potential confounders of baseline characteristics and surgical parameters, a propensity score matching analysis was performed. As a sensitivity analysis, ordinal logistic regression analysis was performed for AKI using inverse probability of treatment weighting (IPTW).

RESULTS

The incidence of AKI was significantly higher in the saline group (n = 88/174, 50.6%) than in the balanced group (n = 67/174, 38.5%) after matching (P = .010). The incidence of stage 2 or 3 AKI was also significantly higher in the saline group (n = 26/174, 14.9%) than in the balanced group (n = 43/174, 24.7%) after matching (P = .022). The length of hospital stay was significantly longer in the saline group than in the balanced group after matching. Ordinal logistic regression analysis using IPTW showed that the saline group showed a significant association of saline administration with the risk of AKI (odds ratio 1.23, 95% CI 1.05-1.28, P = .013).

CONCLUSION

Our propensity score analysis using propensity score matching and IPTW showed that normal saline administration during LDLT is associated with a high risk of postoperative AKI and longer hospital stays. However, our results should be interpreted carefully due to the relatively long period of data collection.

Comparison of Fluid Replacement with Sterofundin ISO® vs. Deltajonin® in Infants Undergoing Craniofacial Surgery-A Retrospective Study

In recent decades, infusion solutions such as NaCl 0.9% and lactate Ringer's solution have been replaced in clinical practice. Since 2017, the national guidelines for perioperative infusion therapy in children recommend balanced isotonic solutions to maintain fluid balance. The composition of balanced infusion solutions varies with respect to their electrolyte content. Hyperchloremia may be mistaken for hypovolemia and may interfere with volume therapy in pediatric patients. Sterofundin ISO® balanced solution contains 127 mmol/L chloride and may cause hyperchloremic acidosis if administered in large volumes.

OBJECTIVES

The purpose of this study was to compare the effects of Sterofundin ISO® (SF) therapy with the balanced isochloremic solution Deltajonin® (DJ) (106 mmol/L chloride) on the acid-base status in infants undergoing craniofacial surgery.

METHODS

This retrospective, non-blinded study included 100 infants undergoing craniectomy due to isolated nonsyndromic sagittal craniosynostosis. The first 50 infants received Sterofundin ISO®. Due to changes in national guidelines, the infusion was changed to the isoionic Deltajonin® in an additional 50 infants in 2017. Pre- and postoperative values of chloride, pH, base excess, bicarbonate, and albumin and phosphate were determined, and the strong-ion difference, strong-ion gap, anion gap, and weak acids were calculated.

RESULTS

Both groups were comparable in terms of their age, sex, underlying disease, preoperative electrolytes (except K at 3.9 ± 0.3 mmol/L (SF) vs. 4.1 ± 0.3 mmol/L (DJ) and lactate 8.7 ± 2.1 (SF) vs. 9.6 ± 2.6 mmol/L (DJ)). In the Sterofundin ISO® group, hyperchloremic metabolic acidosis was observed in 19 patients, whereas only 2 infants in the Deltajonin® group had hyperchloremic metabolic acidosis. The postoperative chloride level was 111 ± 2.7 mmol/L (SF) vs. 108 ± 2.4 mmol/L (DJ). The difference in anion gap was 12.5 ± 3.0 mmol/L (SF) vs. 14.6 ± 2.8 mmol/L (DJ), and the difference in SIDa (apparent strong-ion difference) was 30.9 mmol/L (SF) vs. 33.8 mmol/L (DJ).

CONCLUSIONS

Hyperchloremic acidosis can be induced by the volume replacement with high-chloride-concentration crystalloids such as Sterofundin ISO®. This can be detected using the Stewart model.

A critical review of the perioperative fluid therapy and hemodynamic monitoring recommendations of the Enhanced Recovery of the Adult Pathway (RICA): A position statement of the fluid therapy and hemodynamic monitoring Subcommittee of the Hemostasis, Transfusion Medicine and Fluid Therapy Section (SHTF) of the Spanish Society of Anesthesiology and Critical Care (SEDAR)

In an effort to standardize perioperative management and improve postoperative outcomes of adult patients undergoing surgery, the Ministry of Health, through the Spanish Multimodal Rehabilitation Group (GERM), and the Aragonese Institute of Health Sciences, in collaboration with multiple Spanish scientific societies and based on the available evidence, published in 2021 the Spanish Intensified Adult Recovery (RICA) guideline. This document includes 12 perioperative measures related to fluid therapy and hemodynamic monitoring. Fluid administration and hemodynamic monitoring are not straightforward but are directly related to postoperative patient outcomes. The Fluid Therapy and Hemodynamic Monitoring Subcommittee of the Hemostasis, Transfusion Medicine and Fluid Therapy Section (SHTF) of the Spanish Society of Anesthesiology and Critical Care (SEDAR) has reviewed these recommendations and concluded that they should be revised as they do not follow an adequate methodology.

Role of Crystalloids in the Perioperative Setting: From Basics to Clinical Applications and Enhanced Recovery Protocols

Perioperative fluid management, a critical aspect of major surgeries, is characterized by pronounced stress responses, altered capillary permeability, and significant fluid shifts. Recognized as a cornerstone of enhanced recovery protocols, effective perioperative fluid management is crucial for optimizing patient recovery and preventing postoperative complications, especially in high-risk patients. The scientific literature has extensively investigated various fluid infusion regimens, but recent publications indicate that not only the volume but also the type of fluid infused significantly influences surgical outcomes. Adequate fluid therapy prescription requires a thorough understanding of the physiological and biochemical principles that govern the body's internal environment and the potential perioperative alterations that may arise. Recently published clinical trials have questioned the safety of synthetic colloids, widely used in the surgical field. A new clinical scenario has arisen in which crystalloids could play a pivotal role in perioperative fluid therapy. This review aims to offer evidence-based clinical principles for prescribing fluid therapy tailored to the patient's physiology during the perioperative period. The approach combines these principles with current recommendations for enhanced recovery programs for surgical patients, grounded in physiological and biochemical principles.

Intraoperative use of balanced crystalloids versus 0.9% saline: a systematic review and meta-analysis of randomised controlled studies

BACKGROUND

The evidence regarding optimal crystalloid use in the perioperative period remains unclear. As the primary aim of this study, we sought to summarise the data from RCTs examining whether use of balanced crystalloids compared with 0.9% saline (saline) leads to differences in patient-important outcomes.

METHODS

We searched Ovid MEDLINE, Embase, the Cochrane library, and Clinicaltrials.gov, from inception until December 15, 2022, and included RCTs that intraoperatively randomised adult participants to receive either balanced fluids or saline. We pooled data using a random-effects model and present risk ratios (RRs) or mean differences (MDs), along with 95% confidence intervals (CIs). We assessed individual study risk of bias using the modified Cochrane tool, and certainty of evidence using GRADE.

RESULTS

Of 5959 citations, we included 38 RCTs (n=3776 patients). Pooled analysis showed that intraoperative use of balanced fluids compared with saline had an uncertain effect on postoperative mortality analysed at the longest point of follow-up (RR 1.51, 95% CI: 0.42-5.36) and postoperative need for renal replacement therapy (RR 0.95, 95% CI: 0.56-1.59), both very low certainty. Furthermore, use of balanced crystalloids probably leads to a higher postoperative serum pH (MD 0.05, 95% CI: 0.04-0.06), moderate certainty.

CONCLUSIONS

Use of balanced crystalloids, compared with saline, in the perioperative setting has an uncertain effect on mortality and need for renal replacement therapy but probably improves postoperative acid-base status. Further research is needed to determine whether balanced crystalloid use affects patient-important outcomes.

CLINICAL TRIAL REGISTRATION

CRD42022367593.

Crystalloid Solutions in Hospital: A Review of Existing Literature

Intravenous fluids (IVF) like normal saline (NS) and Ringer's lactate (RL) are often crucial in the management of hospitalized patients. Mishandling these fluids can lead to complications in about 20% of patients receiving them. In this review, we present the current evidence through the identification of observational studies and randomized trials that observed the optimal use of IVF. We found that NS may cause hyperchloremic metabolic acidosis in surgical patients, but there is no clear difference in mortality and long-term outcomes between NS and balanced crystalloids. Critically ill patients, particularly those in sepsis, benefit from balanced crystalloids, as high chloride content fluids like NS increase the risk of complications and mortality. In pancreatitis, NS has been shown to increase the risk of ICU admission when compared to RL; however, there is no significant difference in long-term outcomes and mortality between the fluids. RL is preferred for burns due to its isotonicity and lack of protein, preventing edema formation in an already dehydrated state. Plasma-lyte may resolve diabetic ketoacidosis faster, while prolonged NS use can lead to metabolic acidosis, acute kidney injury, and cerebral edema. In conclusion, NS, RL, and plasma-lyte are the most commonly used isotonic IVF in the hospital population. Incorrect choice of fluids in a different clinical scenario can lead to worse outcomes.

Postoperative Risk of Transfusion After Reversal of Residual Neuromuscular Block With Sugammadex Versus Neostigmine: A Retrospective Cohort Study

BACKGROUND

Sugammadex and neostigmine are routinely used to reverse residual neuromuscular blocks at the end of surgery. Sugammadex has been linked with prolongation of laboratory coagulation markers, but clinical relevance on postoperative blood loss and transfusions remains unclear.

METHODS

In this retrospective, single-center, cohort study, we analyzed medical records of adult patients having noncardiac surgery who were given sugammadex or neostigmine from May 2016 to December 2020. Our primary outcome was the incidence of any postoperative transfusion of red blood cells, and/or fresh-frozen plasma, and/or platelets. Secondary outcomes were duration of hospitalization, need for resurgery, and postoperative intensive care unit (ICU) admission. After propensity score weighting, the odds ratio (OR) for postoperative transfusion was assessed in both groups (sugammadex versus neostigmine) using a generalized estimation equation to count within-subject correlation weighted by the inverse propensity score.

RESULTS

Out of 39,325 eligible surgeries, 33,903 surgeries in 29,062 patients were included in the analysis; with 4581 patients receiving sugammadex and 29,322 patients receiving neostigmine. The raw incidence of postoperative transfusion was 7.40% in sugammadex and 7.45% in the neostigmine group. After weighting by propensity score, the incidence of postoperative transfusion was 8.01% in the sugammadex and 7.38% in the neostigmine group (OR, 1.11 [95% confidence interval [CI], 0.97-1.26; P = .118]). There was no difference in duration of hospitalization and need for resurgery, but odds of postoperative ICU admission were significantly higher for patients receiving sugammadex than those receiving neostigmine (OR, 1.33 [98.33% CI, 1.17-1.52; P < .0001]). Our a priori planned analysis of coagulation laboratory parameters could not be completed because of a high amount of missing laboratory data.

CONCLUSIONS

There is no statistically significant nor clinically important difference in the risk of postoperative transfusion in patients receiving sugammadex or neostigmine.

Normal saline versus balanced crystalloids in patients with prerenal acute kidney injury and pre-existing chronic kidney disease

Introduction Normal saline (N/S) and Ringer's-Lactate (L/R), are administered in everyday clinical practice. Despite that, N/S increases the risk of sodium overload and hyperchloremic metabolic acidosis. In contrast, L/R has lower sodium content, significantly less chloride and contains lactates. In this study we compare the efficacy of L/R versus N/S administration in patients with prerenal acute kidney injury (AKI) and pre-established chronic kidney disease (CKD). Methods In this prospective open-label study we included patients with prerenal AKI and previously known CKD stage III-V without need for dialysis. Patients with other forms of AKI, hypervolemia or hyperkalemia were excluded. Patients received either N/S or L/R intravenously at a dose of 20 ml/kg body-weight/day. We studied kidney function at discharge and at 30 days, duration of hospitalization, acid-base balance and the need for dialysis. Results We studied 38 patients and 20 were treated with N/S. Kidney function improvement during hospitalization and at 30 days after discharge, was similar between the two groups. Duration of hospitalization was also similar. Anion-gap improvement as expressed with Δanion-gap between discharge and admission day was higher in those patients that received L/R in comparison to those that received N/S and pH increase (ΔpH) was slightly higher in the L/R group. No patient required dialysis. Conclusions Administration of L/R or N/S to patients with prerenal AKI and pre-established CKD had no significant difference in short or long term kidney function but L/R showed a better profile in acid-base balance improvement and Cl- overload in comparison to N/S.

Haemodynamic monitoring and management in patients having noncardiac surgery: A survey among members of the European Society of Anaesthesiology and Intensive Care

BACKGROUND

Haemodynamic monitoring and management is a mainstay of peri-operative anaesthetic care.

OBJECTIVE

To determine how anaesthesiologists measure and manage blood pressure and cardiac output, and how they guide fluid administration and assess fluid responsiveness in patients having noncardiac surgery.

DESIGN

Web-based survey.

SETTING

Survey among members of the European Society of Anaesthesiology and Intensive Care (ESAIC) in October and November 2021.

PARTICIPANTS

ESAIC members responding to the survey.

MAIN OUTCOME MEASURES

Respondents' answers to 30 questions on haemodynamic monitoring and management, and fluid therapy.

RESULTS

A total of 615 fully completed surveys were analysed. Arterial catheters are usually not placed before induction of general anaesthesia (378/615; 61%) even when invasive blood pressure monitoring is planned. Mean arterial pressure (532/615; 87%) with lower intervention thresholds of 65 mmHg (183/531; 34%) or 20% below pre-operative baseline (166/531; 31%) is primarily used to guide blood pressure management. Cardiac output is most frequently measured using pulse wave analysis (548/597; 92%). However, only one-third of respondents (almost) always use cardiac output to guide haemodynamic management in high-risk patients (225/582; 39%). Dynamic cardiac preload variables are more frequently used to guide haemodynamic management than cardiac output [pulse pressure variation (almost) always: 318/589; 54%]. Standardised treatment protocols are rarely used for haemodynamic management (139/614; 23%). For fluid therapy, crystalloids are primarily used as maintenance fluids, to treat hypovolaemia, and for fluid challenges. The use of 0.9% saline and hydroxyethyl starch has declined over the last decade. The preferred methods to assess fluid responsiveness are dynamic preload variables and fluid challenges, most commonly with 250 ml of fluid (319/613; 52%).

CONCLUSION

This survey provides important information how anaesthesiologists currently measure and manage blood pressure and cardiac output, and how they guide fluid administration in patients having noncardiac surgery.

The Effects of sodium bicarbonate Ringer’s solution on acute kidney injury and the clinical outcomes after liver transplantation: A randomized controlled trial

Background: Acute kidney injury is the most common complication after liver transplantation. Sodium bicarbonate Ringer’s solution is a new type of crystalloid solution that has been recently used in the clinical setting. Whether sodium bicarbonate Ringer’s solution reduces the occurrence of postoperative AKI and improves the clinical outcomes of liver transplantation patients is not clear.

Objective: To compare the effects of sodium bicarbonate Ringer’s solution versus normal saline on acute kidney injury and clinical outcomes following classic orthotopic liver transplantation.

Methods: Sixty-four participants were randomly assigned to the sodium bicarbonate Ringers (BRS) group or the normal saline (NS) group. The primary outcomes were the incidence and severity of acute kidney injury after liver transplantation. The secondary outcomes included the rate of renal replacement therapy, length of mechanical ventilation, stay in the ICU, stay in the hospital after surgery and 30-day mortality. Other outcomes included the concentration of sodium, chloride, bicarbonate, anion gap, lactate concentration and changes in chloride preoperatively and postoperatively.

Result: Sixty-two patients completed the trial and were analyzed, with 31 patients in each group. There was a significantly lower rate of postoperative acute kidney injury in the BRS group (14/31, 45.2%) than in the NS group (24/31, 77.4%), with a relative risk of 0.58 (95% CI, 0.38–0.90; p = 0.009). The severity of AKI in the BRS group was lower than that in the NS group (Z = -2.932, p = 0.003). There was no significant difference observed in the secondary outcomes. For other outcomes, the concentration of preoperative sodium was lower than postoperative sodium in the NS group (137.2 vs. 140.4, p = 0.009). The concentration of preoperative chloride was lower than that of postoperative chloride in the NS group (102.9 vs. 106.2, p < 0.001). The change in the concentration of chloride in the BRS group was lower than that in the NS group (1.6 vs. 4.7, p = 0.006).

Conclusion: Sodium bicarbonate Ringer’s solution reduced the incidence and severity of acute kidney injury after classic orthotopic liver transplantation.

Perioperative Fluid Management in Surgical Patients: A Review

Intravenous (IV) fluids are one of the most widely prescribed medications. Despite their frequent usage, IV fluids are often not used appropriately. High-quality evidence to guide the surgeon in the perioperative period is sparse. A plethora of choices for IV fluids exists with limited evidence to help guide the surgeon in specific patient populations and situations. To address this, the authors have set out to provide a critical review of commonly used IV fluids to treat surgical patients. Gaps in the existing literature for the surgical population will also be discussed as potential target areas for future research.

Fluid management in hospitalized pediatric patients

The proper use of intravenous fluids has likely been responsible for saving more lives than any other group of substances. Proper use includes prescribing an appropriate electrolyte and carbohydrate solution, at a calculated rate or volume, for the right child, at the right time. Forming intravenous fluid plans for hospitalized children requires an understanding of water and electrolyte physiology in healthy children and how different pathology deviates from the norm. This review highlights fluid management in several disease types, including liver disease, diabetic ketoacidosis, syndrome of inappropriate antidiuretic hormone, diabetes insipidus, kidney disease, and intestinal failure as well as in those with nonphysiologic fluid losses. For each disease, the review discusses specific considerations, evaluations, and management strategies to consider when customizing intravenous fluid plans. Ultimately, all hospitalized children should receive an individualized fluid plan with recurrent evaluations and fluid modifications to provide optimal care.

Guidelines for the choice of intravenous fluids for vascular filling in critically ill patients, 2021

PURPOSE

To provide recommendations for the appropriate choice of fluid therapy for resuscitation of critically ill patients.

DESIGN

A consensus committee of 24 experts from the French Society of Anaesthesia and Intensive Care Medicine (Société française d'anesthésie et de réanimation, SFAR) and the French Society of Emergency Medicine (Société française de médecine d'urgence, SFMU) was convened. A formal conflict-of-interest policy was developed at the onset of the process and enforced throughout. The entire guideline elaboration process was conducted independently of any industry funding. The authors were advised to follow the principles of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system to guide their assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasised. Some recommendations were left ungraded.

METHODS

Four fields were defined: patients with sepsis or septic shock, patients with haemorrhagic shock, patients with acute brain failure, and patients during the peripartum period. For each field, the panel focused on two questions: (1) Does the use of colloids, as compared to crystalloids, reduce morbidity and mortality, and (2) Does the use of some specific crystalloids effectively reduce morbidity and mortality. Population, intervention, comparison, and outcomes (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. The analysis of the literature and the recommendations were then conducted according to the GRADE methodology.

RESULTS

The SFAR/SFMU guideline panel provided nine statements on the appropriate choice of fluid therapy for resuscitation of critically ill patients. After two rounds of rating and various amendments, strong agreement was reached for 100% of the recommendations. Out of these recommendations, two have a high level of evidence (Grade 1 +/-), six have a moderate level of evidence (Grade 2 +/-), and one is based on expert opinion. Finally, no recommendation was formulated for two questions.

CONCLUSIONS

Substantial agreement among experts has been obtained to provide a sizable number of recommendations aimed at optimising the choice of fluid therapy for resuscitation of critically ill patients.

Order Substitutions and Education for Balanced Crystalloid Solution Use in an Integrated Health Care System and Association With Major Adverse Kidney Events

Importance

Trials comparing balanced crystalloids with normal saline have yielded mixed results regarding reductions in kidney complications and mortality for hospitalized patients receiving intravenous fluids.

Objective

To evaluate the association of a multifaceted implementation program encouraging the preferential use of lactated Ringer solution with patient outcomes and intravenous fluid-prescribing practices in a large, multilevel health care system.

Design, Setting, and Participants

This type 2 hybrid implementation and comparative effectiveness study enrolled all patients 18 years or older who received 1 L or more of intravenous fluids while admitted to an emergency department and/or inpatient unit at 1 of 22 hospitals in Idaho and Utah between November 1, 2018, and February 29, 2020. An interrupted time series analysis was used to assess study outcomes before and after interventions to encourage use of lactated Ringer solution.

Exposures

Implementation program combining order set modification, electronic order entry alerts, and sequential clinician-targeted education to encourage prescribing of lactated Ringer solution instead of normal saline.

Main Outcomes and Measures

The primary implementation outcome was the patient-level proportion of intravenous fluids that was balanced crystalloids. The primary effectiveness outcome was the incidence of major adverse kidney events (MAKE30)-a composite of new persistent kidney dysfunction, new initiation of dialysis, and death-at 30 days.

Results

Among 148 423 patients (median [IQR] age, 47 [30-67] years; 91 302 women [61%]), the proportion of total fluids received that was lactated Ringer solution increased from 28% to 75% in the first week vs the last week of the study (immediate implementation effect odds ratio [OR], 3.44; 95% CI, 2.79-4.24). The estimated MAKE30 absolute risk reduction was 2.2% (95% CI, 1.3%-3.3%) based on interrupted time series analysis showing a decrease in the week-on-week trend for MAKE30 (OR difference, 0.03; 95% CI, 0.03-0.03, P < .001). The immediate postimplementation OR for MAKE30 was 0.88 (95% CI, 0.76-1.01), with a decrease in persistent kidney dysfunction (OR, 0.80; 95% CI, 0.69-0.93) and mortality (OR, 0.78; 95% CI, 0.65-0.93) but not dialysis (OR, 1.00; 95% CI, 0.76-1.32).

Conclusions and Relevance

In this comparative effectiveness study, an implementation program was associated with an increase in the proportion of fluids administered as lactated Ringer solution compared with normal saline and was associated with a reduction in MAKE30 events among patients treated in a large integrated health care system.

In Vivo Metabolic Analysis of the Anticancer Effects of Plasma-Activated Saline in Three Tumor Animal Models

In recent years, the emerging technology of cold atmospheric pressure plasma (CAP) has grown rapidly along with the many medical applications of cold plasma (e.g., cancer, skin disease, tissue repair, etc.). Plasma-activated liquids (e.g., culture media, water, or normal saline, previously exposed to plasma) are being studied as cancer treatments, and due to their advantages, many researchers prefer plasma-activated liquids as an alternative to CAP in the treatment of cancer. In this study, we showed that plasma-activated-saline (PAS) treatment significantly inhibited tumor growth, as compared with saline, in melanoma, and a low-pH environment had little effect on tumor growth in vivo. In addition, based on an ultra-high-performance liquid tandem chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) analysis of tumor cell metabolism, the glycerophospholipid metabolic pathway was the most susceptible metabolic pathway to PAS treatment in melanoma in vitro and in vivo. Furthermore, PAS also inhibited cell proliferation in vivo in oral tongue squamous-cell cancer and non-small-cell lung cancer. There were few toxic side effects in the three animal models, and the treatment was deemed safe to use. In the future, plasma-activated liquids may serve as a potential therapeutic approach in the treatment of cancer.

Observational study on fluid therapy management in surgical adult patients

Background

Perioperative fluid therapy management is changing due to the incorporation of different fluids, surgical techniques, and minimally invasive monitoring systems. The objective of this study was to explore fluid therapy management during the perioperative period in our country.

Methods

We designed the Fluid Day study as a cross-sectional, multicentre, observational study. The study was performed in 131 Spanish hospitals in February 2019. We included adult patients undergoing general anaesthesia for either elective or non-elective surgery. Demographic variables were recorded, as well as the type and total volume of fluid administered during the perioperative period and the monitorization used. To perform the analysis, patients were categorized by risk group.

Results

We recruited 7291 patients, 6314 of which were included in the analysis; 1541 (24.4%) patients underwent high-risk surgery, 1497 (23. 7%) were high risk patients, and 554 (8.7%) were high-risk patients and underwent high-risk surgery; 98% patients received crystalloids (80% balanced solutions); intraoperative colloids were used in 466 patients (7.51%). The hourly intraoperative volume in mL/kg/h and the median [Q1; Q3] administered volume (mL/kg) were, respectively, 6.67 [3.83; 8.17] ml/Kg/h and 13.9 [9.52;5.20] ml/Kg in low-risk patients undergoing low- or intermediate-risk surgery, 6 [4.04; 9.08] ml/Kg/h and 15.7 [10.4;24.5] ml/Kg in high- risk patients undergoing low or intermediate-risk surgery, 6.41 [4.36; 9.33] ml/Kg/h and 20.2 [13.3;32.4] ml/Kg in low-risk patients undergoing high-risk surgery, and 5.46 [3.83; 8.17] ml/Kg/h and 22.7[14.1;40.9] ml/Kg in high-risk patients undergoing high- risk surgery . We used advanced fluid monitoring strategies in 5% of patients in the intraoperative period and in 10% in the postoperative period.

Conclusions

The most widely used fluid was balanced crystalloids. Colloids were used in a small number of patients. Hourly surgery volume tended to be more restrictive in high-risk patients but confirms a high degree of variation in the perioperatively administered volume. Scarce monitorization was observed in fluid therapy management.

Trial registration

Clinical Trials: NCT03630744.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01518-z.

Battle of the Crystalloids in the Operating Room: A Literature Review

PURPOSE

The purpose of this article is to synthesize the evidence regarding the commonalities and differences between the three most common crystalloid solutions used in the operating room (normal saline [NS], lactated Ringer's [LR], and Plasmalyte [PL]) in order to determine best practice.

DESIGN

This study is an integrative review of literature.

METHODS

A review of the literature was conducted using the PubMed, CINAHL Plus, and Cochrane Library databases. The inclusion criteria included adult patients undergoing surgery who received either NS, LR, and/or PL (or similar solutions) for fluid maintenance therapy.

FINDINGS

A total of 15 articles from 2008 to 2020 conducted in a surgical setting were selected for the review; eleven randomized controlled studies, three observational studies, and one cohort-controlled trial.

CONCLUSIONS

The findings suggest balanced crystalloid solutions are superior to NS in the operating room in terms of maintaining a stable acid-base balance. PL is preferable to LR because it most closely resembles plasma concentration. Future research is needed to determine the cost-effectiveness of the solutions.

[Intravenous fluid therapy and acute kidney injury - What's new?]

Optimization of intravascular volume is crucial for patients who are at risk or undergo Acute Kidney Injury. In sepsis or after acute fluid loss extensive fluid expansion is mostly needed. However, in cardiorenal syndroms fluid overload can even lead to AKI itself and reduction of intravascular volume is needed. Thus, an individualized fluid guidance in terms of a "fluid management stewartship" for the right patient, the right drug, the right route and the right dose 1 has to be applied.

Association between the use of balanced fluids and outcomes in critically ill children: a before and after study

Background

Hyperchloremia and chloride load have been associated with worse clinical outcomes in critically ill patients. We sought to evaluate the electrolyte profile and clinical outcomes associated with a unit-wide transition from saline to balanced fluids for resuscitation and maintenance fluids in a pediatric intensive care unit (PICU).

Methods

A before and after analysis of all patients admitted to the PICU in a large, urban, academic hospital between August 2018 and March 2020. The transition from the use of saline to the use of balanced fluids for both resuscitation and maintenance fluid as standard care occurred in June 2019. The primary outcome was day 3 acute kidney injury (AKI). The secondary outcomes included mortality, ventilator-free days (VFDs), need for renal replacement therapy (RRT), hospital length of stay (LOS), and electrolyte abnormalities.

Results

Overall, 2863 patients (47% female) with a day 3 AKI rate of 12.9% (n = 130) and a mortality rate of 2.8% (n = 79) were included. After adjusting for confounders (age, PRISM III, mechanical ventilation, and immunocompromised state, septic shock), there were no significant differences in the odds of day 3 AKI (pre 13%, post 12.5%; adjusted odds ratio [aOR] 0.96, 95%CI 0.65–1.42). There were no differences in the secondary outcomes. The post-intervention period had fewer patients with hyperchloremia (pre 15.5% vs. post 10.4%, p =  < 0.0001) and hyperkalemia (pre 3.2% vs. post 1.4%, p = 0.02) and more patients with hypochloremia (pre 9.5% vs. post 14.4%, p =  < 0.0001) and hypokalemia (pre 38.2% vs. post 47.2%, p =  < 0.0001). In reference to the normochloremic cohort, the hypochloremic cohort had an increase in day 3 AKI, need for RRT, hyperchloremia, and hyperkalemia, and a decrease in hypokalemia; and the hyperchloremic cohort had an increase in VFD and a decrease in hospital LOS.

Conclusions

Following a unit-wide implementation of balanced fluids as standard care, there were no differences in rates of day 3 AKI or other clinical outcomes. However, there were lower rates of hyperkalemia and hyperchloremia and higher rates of hypokalemia and hypochloremia. Further evaluation of the effect of balanced fluids and the clinical significance of electrolyte abnormalities in critically ill children is needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03705-3.

Perioperative Normal Saline Administration and Delayed Graft Function in Patients Undergoing Kidney Transplantation: A Retrospective Cohort Study

BACKGROUND

Perioperative normal saline administration remains common practice during kidney transplantation. The authors hypothesized that the proportion of balanced crystalloids versus normal saline administered during the perioperative period would be associated with the likelihood of delayed graft function.

METHODS

The authors linked outcome data from a national transplant registry with institutional anesthesia records from 2005 to 2015. The cohort included adult living and deceased donor transplants, and recipients with or without need for dialysis before transplant. The primary exposure was the percent normal saline of the total amount of crystalloids administered perioperatively, categorized into a low (less than or equal to 30%), intermediate (greater than 30% but less than 80%), and high normal saline group (greater than or equal to 80%). The primary outcome was the incidence of delayed graft function, defined as the need for dialysis within 1 week of transplant. The authors adjusted for the following potential confounders and covariates: transplant year, total crystalloid volume, surgical duration, vasopressor infusions, and erythrocyte transfusions; recipient sex, age, body mass index, race, number of human leukocyte antigen mismatches, and dialysis vintage; and donor type, age, and sex.

RESULTS

The authors analyzed 2,515 records. The incidence of delayed graft function in the low, intermediate, and high normal saline group was 15.8% (61/385), 17.5% (113/646), and 21% (311/1,484), respectively. The adjusted odds ratio (95% CI) for delayed graft function was 1.24 (0.85 to 1.81) for the intermediate and 1.55 (1.09 to 2.19) for the high normal saline group compared with the low normal saline group. For deceased donor transplants, delayed graft function in the low, intermediate, and high normal saline group was 24% (54/225 [reference]), 28.6% (99/346; adjusted odds ratio, 1.28 [0.85 to 1.93]), and 30.8% (277/901; adjusted odds ratio, 1.52 [1.05 to 2.21]); and for living donor transplants, 4.4% (7/160 [reference]), 4.7% (14/300; adjusted odds ratio, 1.15 [0.42 to 3.10]), and 5.8% (34/583; adjusted odds ratio, 1.66 [0.65 to 4.25]), respectively.

CONCLUSIONS

High percent normal saline administration is associated with delayed graft function in kidney transplant recipients.

EDITOR’S PERSPECTIVE

Balanced crystalloids versus saline in critically ill adults with low plasma bicarbonate: A secondary analysis of a clinical trial

PURPOSE

We aimed to determine if balanced crystalloids compared with saline improve outcomes in critically ill adults admitted with low plasma bicarbonate.

MATERIALS AND METHODS

We performed a secondary analysis of the Isotonic Solutions and Major Adverse Renal Events Trial (SMART). We included patients who presented to the Emergency Department with a first measured plasma bicarbonate less than 20 mmol/L. Among these patients, we compared the effect of balanced crystalloid versus saline on the primary outcome of major adverse kidney events within 30 days (MAKE30), defined as a composite of death, new renal-replacement therapy, or persistent renal dysfunction (final inpatient creatinine ≥200% baseline). Secondary outcomes included 30 day in-hospital mortality, receipt of new RRT, persistent renal dysfunction, incident AKI, and vasopressor-free days.

RESULTS

Among the 2029 patients with an initial plasma bicarbonate concentration < 20 mmol/L, there was no difference in the incidence of MAKE30 between those assigned to balanced crystalloid versus saline (21.8% vs 21.3%; P = 0.93). Secondary outcomes were similar between the balanced crystalloid and saline groups.

CONCLUSIONS

Among critically ill adults presenting to the Emergency Department, initial plasma bicarbonate concentration does not appear to be a useful marker to guide the selection of balanced crystalloid versus saline.

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.

[Solutions for Fluid Treatment and Outcome - an Update]

Fluid therapy is one of the most frequently used medical interventions with the aim of normalizing the fluid balance. A decisive criterion for the efficiency of fluid or volume replacement is the functionality of the glycocalyx, a thin endothelial glycoprotein layer. Its solidity is an essential factor for fluid exchange and transport from the vascular system to the tissue. The recently described revised Starling principle extends the understanding considerably. From a clinical point of view, fluid treatment should aim for timely euvolemia without inducing relevant side effects. Both crystalloid and natural or synthetic colloidal solutions are available. In the case of crystalloid solutions, the so-called balanced solutions seem to be associated with fewer side effects. If the vascular barrier is intact, colloid solutions have a higher volume effect, but may have significant side effects limiting their use. At least in Europe, some synthetic colloids shall therefore no longer be used in critically ill patients. In contrast, treatment with albumin 20% in hypalbuminemic patients with cardiovascular disease leads to a reduced incidence of acute kidney injury and has also been associated with other clinical benefits. To what extent future, individualized therapeutic approaches employing colloids will influence the outcome is currently speculative.

Effect of 0.9% NaCl compared to plasma-lyte on biomarkers of kidney injury, sodium excretion and tubular transport proteins in patients undergoing primary uncemented hip replacement - a randomized trial

Background

Isotonic saline (IS) is widely used to secure perioperative cardiovascular stability. However, the high amount of chloride in IS can induce hyperchloremic acidosis. Therefore, IS is suspected to increase the risk of acute kidney injury (AKI). Biomarkers may have potential as indicators.

Methods

In a double-blinded, placebo-controlled study, 38 patients undergoing primary uncemented hip replacement were randomized to IS or PlasmaLyte (PL). Infusion was given during surgery as 15 ml/kg the first hour and 5 ml/kg the following two hours. Urinary samples were collected upon admission and the day after surgery. As surgery was initiated, urine was collected over the course of 4 h. Hereafter, another urine collection proceeded until the morning. Urine was analyzed for markers of AKI neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1). Arterious and venous blood samples for measurements of pH and plasma electrolytes including chloride (p-Cl) were collected as surgery was initiated, at the end of surgery and the following morning.

Results

IS induced an increase in p-Cl (111 ± 2 mmol/L after IS and 108 ± 3 after PL, p = 0.004) and a decrease in pH (7.39 ± 0.02 after IS and 7.43 ± 0.03 after PL, p = 0.001). Urinary NGAL excretion increased in both groups (ΔNGAL: 5.5 [4.1; 11.7] μg/mmol creatinine p = 0.004 after IS vs. 5.5 [2.1;9.4] μg/mmol creatinine after PL, p < 0.001). No difference was found between the groups (p = 0.839). Similarly, urinary KIM-1 excretion increased in both groups (ΔKIM-1: IS 115.8 [74.1; 156.2] ng/mmol creatinine, p < 0.001 vs. PL 152.4 [120.1; 307.9] ng/mmol creatinine, p < 0.001). No difference between the groups (p = 0.064).

FE_Na increased (1.08 ± 0.52% after IS and 1.66 ± 1.15% after PL, p = 0.032). ENaC excretion was different within groups (p = 0.019).

Conclusion

A significantly higher plasma chloride and a lower pH was present in the group receiving isotonic saline. However, u-NGAL and u-KIM-1 increased significantly in both groups after surgery despite absence of changes in creatinine. These results indicate that surgery induced subclinical kidney injury. Also, the IS group had a delayed sodium excretion as compared to the PL group which may indicate that IS affects renal sodium excretion differently from PL.

Trial registration

ClinicalTrials.gov Identifier: NCT02528448, 19/08/2015

[Perioperative fluid management in major abdominal surgery]

Intravascular fluid administration belongs to the cornerstones of perioperative treatment with a substantial impact on surgical outcome especially with respect to major abdominal surgery. By avoidance of hypovolemia and hypervolemia, adequate perioperative fluid management significantly contributes to the reduction of insufficient tissue perfusion as a determinant of postoperative morbidity and mortality. The effective use of intravascular fluids requires detailed knowledge of the substances as well as measures to guide fluid therapy. Fluid management already starts preoperatively and should be continued in the postoperative setting (recovery room, peripheral ward) considering a patient-adjusted and surgery-adjusted hemodynamic monitoring. Communication between all team members participating in perioperative care is essential to optimize fluid management.

Acute kidney injury after aneurysmal subarachnoid hemorrhage: is chloride really responsible?

Sadan et al. find an association between acute kidney injury and high chloride containing a hypertonic solution. Recent large prospective non-randomized studies bring conflicting results on the relationship between chloride and acute kidney injury. We discuss Sadan et al.'s results according to the recent literature.

Peak Serum Chloride and Hyperchloremia in Patients Undergoing Cardiac Surgery Is Not Explained by Chloride-Rich Intravenous Fluid Alone: A Post-Hoc Analysis of the LICRA Trial

OBJECTIVES

With the exception of 0.9% saline, little is known about factors that may contribute to increased serum chloride concentration (S_Cl^-) in patients undergoing cardiac surgery. For the present study, the authors sought to characterize the association between administered chloride load from intravenous fluid and other perioperative variables, with peak perioperative S_Cl^-.

DESIGN

Secondary analysis of data from a previously published controlled clinical trial in which patients were assigned to a chloride-rich or chloride-limited perioperative fluid strategy (NCT02020538).

SETTING

Academic medical center.

PARTICIPANTS

The study comprised 1,056 adult patients with normal preoperative S_Cl^- undergoing cardiac surgery.

INTERVENTIONS

None MEASUREMENTS AND MAIN RESULTS: Peak perioperative S_Cl^- and hyperchloremia, defined as peak S_Cl^- >110 mmol/L, were selected as co-primary endpoints. Regression modeling identified factors independently associated with these endpoints. Mean (standard deviation) peak perioperative S_Cl^- was 114 (5) mmol/L, and hyperchloremia occurred in 824 (78.0%) of the cohort. In addition to administered volume of 0.9% saline, multivariate linear and logistic regression modeling consistently associated preoperative S_Cl^- (regression coefficient 0.5; 95% confidence interval [CI] 0.4-0.6 mmol/L; odds ratio 1.60; 95% CI 1.41-1.82 per 1 mmol/L increase) and cardiopulmonary bypass duration (regression coefficient 0.1; 95% CI 0.1-0.2 mmol/L; odds ratio 1.12; 95% CI 1.06-1.19 per 10 minutes) with both co-primary outcomes. Multivariate modeling only explained approximately 50% of variability in peak S_Cl^-.

CONCLUSIONS

The present study's data identified an association for both 0.9% saline administration and other nonfluid variables with peak perioperative S_Cl^- and hyperchloremia. Stand-alone strategies to limit administration of chloride-rich intravenous fluid may have limited ability to prevent hyperchloremia in this setting.

Study Protocol for Better Evidence for Selecting Transplant Fluids (BEST-Fluids): a pragmatic, registry-based, multi-center, double-blind, randomized controlled trial evaluating the effect of intravenous fluid therapy with Plasma-Lyte 148 versus 0.9% saline on delayed graft function in deceased donor kidney transplantation

Background

Delayed graft function, the requirement for dialysis due to poor kidney function post-transplant, is a frequent complication of deceased donor kidney transplantation and is associated with inferior outcomes and higher costs. Intravenous fluids given during and after transplantation may affect the risk of poor kidney function after transplant. The most commonly used fluid, isotonic sodium chloride (0.9% saline), contains a high chloride concentration, which may be associated with acute kidney injury, and could increase the risk of delayed graft function. Whether using a balanced, low-chloride fluid instead of 0.9% saline is safe and improves kidney function after deceased donor kidney transplantation is unknown.

Methods

BEST-Fluids is an investigator-initiated, pragmatic, registry-based, multi-center, double-blind, randomized controlled trial. The primary objective is to compare the effect of intravenous Plasma-Lyte 148 (Plasmalyte), a balanced, low-chloride solution, with the effect of 0.9% saline on the incidence of delayed graft function in deceased donor kidney transplant recipients. From January 2018 onwards, 800 participants admitted for deceased donor kidney transplantation will be recruited over 3 years in Australia and New Zealand. Participants are randomized 1:1 to either intravenous Plasmalyte or 0.9% saline peri-operatively and until 48 h post-transplant, or until fluid is no longer required; whichever comes first. Follow up is for 1 year. The primary outcome is the incidence of delayed graft function, defined as dialysis in the first 7 days post-transplant. Secondary outcomes include early kidney transplant function (composite of dialysis duration and rate of improvement in graft function when dialysis is not required), hyperkalemia, mortality, graft survival, graft function, quality of life, healthcare resource use, and cost-effectiveness. Participants are enrolled, randomized, and followed up using the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry.

Discussion

If using Plasmalyte instead of 0.9% saline is effective at reducing delayed graft function and improves other clinical outcomes in deceased donor kidney transplantation, this simple, inexpensive change to using a balanced low-chloride intravenous fluid at the time of transplantation could be easily implemented in the vast majority of transplant settings worldwide.

Trial registration

Australian New Zealand Clinical Trials Registry: ACTRN12617000358347. Registered on 8 March 2017. ClinicalTrials.gov: NCT03829488. Registered on 4 February 2019.