Balanced Crystalloids versus Saline in the Intensive Care Unit. The SALT Randomized Trial

Association between normal saline infusion volume in the emergency department and acute kidney injury in heat stroke patients: a multicenter retrospective study

BACKGROUND

Previous studies have shown that intravenous normal saline (NS) may be associated with the incidence of acute kidney injury (AKI). This study aimed to evaluate the association between the volume of NS infusion and AKI in heat stroke (HS) patients.

METHODS

This multicenter retrospective cohort study included 138 patients with HS. The primary outcome was the incidence of AKI. Secondary outcomes included the need for continuous renal replacement therapy (CRRT), admission to the intensive care unit (ICU), length of stay in the ICU and hospital, and in-hospital mortality. Multivariate regression models, random forest imputation, and genetic and propensity score matching were used to explore the relationship between NS infusion and outcomes.

RESULTS

The mean volume of NS infusion in the emergency department (ED) was 3.02 ± 1.45 L. During hospitalization, 33 patients (23.91%) suffered from AKI. In the multivariate model, as a continuous variable (per 1 L), the volume of NS infusion was associated with the incidence of AKI (OR, 2.51; 95% CI, 1.43-4.40; p = .001), admission to the ICU (OR, 3.46; 95% CI 1.58-7.54; p = .002), and length of stay in the ICU (β, 1.00 days; 95% CI, 0.44-1.56; p < .001) and hospital (β, 1.41 days; 95% CI, 0.37-2.45; p = .008). These relationships also existed in the forest imputation cohort and matching cohort. There were no differences in the use of CRRT or in-hospital mortality.

CONCLUSIONS

The volume of NS infusion was associated with a significant increase in the incidence of AKI, admission to the ICU, and length of stay in the ICU and hospital among patients with HS.

European Society of Intensive Care Medicine clinical practice guideline on fluid therapy in adult critically ill patients. Part 1: the choice of resuscitation fluids

PURPOSE

This is the first of three parts of the clinical practice guideline from the European Society of Intensive Care Medicine (ESICM) on resuscitation fluids in adult critically ill patients. This part addresses fluid choice and the other two will separately address fluid amount and fluid removal.

METHODS

This guideline was formulated by an international panel of clinical experts and methodologists. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was applied to evaluate the certainty of evidence and to move from evidence to decision.

RESULTS

For volume expansion, the guideline provides conditional recommendations for using crystalloids rather than albumin in critically ill patients in general (moderate certainty of evidence), in patients with sepsis (moderate certainty of evidence), in patients with acute respiratory failure (very low certainty of evidence) and in patients in the perioperative period and patients at risk for bleeding (very low certainty of evidence). There is a conditional recommendation for using isotonic saline rather than albumin in patients with traumatic brain injury (very low certainty of evidence). There is a conditional recommendation for using albumin rather than crystalloids in patients with cirrhosis (very low certainty of evidence). The guideline provides conditional recommendations for using balanced crystalloids rather than isotonic saline in critically ill patients in general (low certainty of evidence), in patients with sepsis (low certainty of evidence) and in patients with kidney injury (very low certainty of evidence). There is a conditional recommendation for using isotonic saline rather than balanced crystalloids in patients with traumatic brain injury (very low certainty of evidence). There is a conditional recommendation for using isotonic crystalloids rather than small-volume hypertonic crystalloids in critically ill patients in general (very low certainty of evidence).

CONCLUSIONS

This guideline provides eleven recommendations to inform clinicians on resuscitation fluid choice in critically ill patients.

Comparison of the efficacy of 0.9% normal saline with balanced crystalloid (Plasmalyte) in maintaining the metabolic profile in head injury patients undergoing evacuation of acute subdural haematoma - A randomised controlled trial

Background and Aims

The choice of intravenous fluids is important in patients with traumatic brain injury (TBI), where large volumes may be required for resuscitation. Our study aimed to compare 0.9% normal saline (NS) with balanced crystalloid (Plasmalyte) in TBI patients in terms of metabolic and coagulation profile, brain relaxation score (BRS) and renal functions using serum urea, creatinine and urinary tissue inhibitor of metalloproteinases-2* insulin-like growth factor binding protein-7, [TIMP-2]*[IGFBP7], value to assess the risk of acute kidney injury.

Methods

This randomised controlled trial on 90 TBI patients undergoing emergency craniotomy and subdural haematoma evacuation was conducted in a tertiary care institute. The patients were randomised to receive either NS (Group NS) or Plasmalyte (Group P) as the intraoperative maintenance fluid. The primary outcome measures included the potential of hydrogen (pH), base excess (BE) and chloride values from an arterial blood gas. The secondary outcomes were the coagulation profile, BRS and urinary [TIMP-2]*[IGFBP7]. The two groups' metabolic profile differences were analysed using two-way repeated analysis of variance. BRS was analysed using the Mann-Whitney U test. A P value < 0.05 was considered to be statistically significant.

Results

The pH and chloride values were significantly higher, and the BE values were significantly lower in Group P compared to Group NS (P < 0.001). Brain relaxation and coagulation profiles were comparable between the two groups. Serum creatinine (P = 0.002) and urinary [TIMP-2]*[IGFBP7] (P = 0.042) were significantly higher in the NS group.

Conclusion

Plasmalyte maintains a more favourable metabolic profile than NS in TBI patients without affecting brain relaxation adversely.

Heterogeneity in the definition of major adverse kidney events: a scoping review

Acute kidney injury (AKI) is associated with persistent renal dysfunction, the receipt of dialysis, dialysis dependence, and mortality. Accordingly, the concept of major adverse kidney events (MAKE) has been adopted as an endpoint for assessing the impact of AKI. However, applied criteria or observation periods for operationalizing MAKE appear to vary across studies. To evaluate this heterogeneity for MAKE evaluation, we performed a systematic scoping review of studies that employed MAKE as an AKI endpoint. Four major academic databases were searched, and we identified 122 studies with increasing numbers over time. We found marked heterogeneity in applied criteria and observation periods for MAKE across these studies, with some even lacking a description of criteria. Moreover, 13 different observation periods were employed, with 30 days and 90 days as the most common. Persistent renal dysfunction was evaluated by estimated glomerular filtration rate (34%) or serum creatinine concentration (48%); however, 37 different definitions for this component were employed in terms of parameters, cut-off criteria, and assessment periods. The definition for the dialysis component also showed significant heterogeneity regarding assessment periods and duration of dialysis requirement (chronic vs temporary). Finally, MAKE rates could vary by 7% [interquartile range: 1.7-16.7%] with different observation periods or by 36.4% with different dialysis component definitions. Our findings revealed marked heterogeneity in MAKE definitions, particularly regarding component assessment and observation periods. Dedicated discussion is needed to establish uniform and acceptable standards to operationalize MAKE in terms of selection and applied criteria of components, observation period, and reporting criteria for future trials on AKI and related conditions.

Comparison of balanced crystalloids versus normal saline in patients with diabetic ketoacidosis: a meta-analysis of randomized controlled trials

Purpose

The optimal resuscitative fluid for patients with diabetic ketoacidosis (DKA) remains controversial. Therefore, our objective was to assess the effect of balanced crystalloids in contrast to normal saline on clinical outcomes among patients with DKA.

Methods

We searched electronic databases for randomized controlled trials comparing balanced crystalloids versus normal saline in patients with DKA, the search period was from inception through October 20th, 2023. The outcomes were the time to resolution of DKA, major adverse kidney events, post-resuscitation chloride, and incidence of hypokalemia.

Results

Our meta-analysis encompassed 11 trials, incorporating a total of 753 patients with DKA. There was no significant difference between balanced crystalloids and normal saline group for the time to resolution of DKA (MD -1.49, 95%CI -4.29 to 1.31, P=0.30, I2 = 65%), major adverse kidney events (RR 0.88, 95%CI 0.58 to 1.34, P=0.56, I2 = 0%), and incidence of hypokalemia (RR 0.80, 95%CI 0.43 to 1.46, P=0.46, I2 = 56%). However, there was a significant reduction in the post-resuscitation chloride (MD -3.16, 95%CI -5.82 to -0.49, P=0.02, I2 = 73%) among patients received balanced crystalloids.

Conclusion

Among patients with DKA, the use of balanced crystalloids as compared to normal saline has no effect on the time to resolution of DKA, major adverse kidney events, and incidence of hypokalemia. However, the use of balanced crystalloids could reduce the post-resuscitation chloride.

Systematic review registration

https://osf.io, identifier c8f3d.

Trimatch comparison of the prognosis of hypochloremia, normolchloremia and hyperchloremia in patients with septic shock

BACKGROUND

Septic shock is a lethal disease, and identifying high-risk patients through noninvasive and widely available biomarkers can help improve global outcomes. While the clinical impact of chloride levels on critically ill patients remains unclear, this study aims to investigate the association between hypochloremia and mortality following ICU admission among septic shock patients.

METHODS

This is an analysis of data stored in the databases of Medical Information Mart for Intensive Care IV (MIMIC-IV). The initial chloride levels were classified ashypochloremia, normal chloraemia, and hyperchloraemia. A multivariate logistic regression model was applied, adjusting for age, lactate, pH, PO2, urine volume, RDW, creatinine, and liver disease, to assess the association between the three categories of chloride levels and mortality.

RESULTS

Of 3726 patients included in the study, 470 patients (12.6%) had hypochloremia on ICU admission. During the follow-up period, 1120 (33.5%) patients died. Hypochloremia was significantly associated with increased mortality and the incidence of AKI after adjusting for several variables.

CONCLUSIONS

Hypochloremia is independently associated with higher hospital mortality, AKI incidence among septic shock patients. However, further high-quality research is necessary to establish the precise relationship between hypochloremia and septic shock prognosis.

Influence of fluid accumulation on major adverse kidney events in critically ill patients - an observational cohort study

BACKGROUND

Fluid accumulation (FA) is known to be associated with acute kidney injury (AKI) during intensive care unit (ICU) stay but data on mid-term renal outcome is scarce. The aim of this study was to investigate the association between FA at ICU day 3 and major adverse kidney events in the first 30 days after ICU admission (MAKE30).

METHODS

Retrospective, single-center cohort study including adult ICU patients with sufficient data to compute FA and MAKE30. We defined FA as a positive cumulative fluid balance greater than 5% of bodyweight. The association between FA and MAKE30, including its sub-components, as well as the serum creatinine trajectories during ICU stay were examined. In addition, we performed a sensitivity analysis for the stage of AKI and the presence of chronic kidney disease (CKD).

RESULTS

Out of 13,326 included patients, 1,100 (8.3%) met the FA definition. FA at ICU day 3 was significantly associated with MAKE30 (adjusted odds ratio [aOR] 1.96; 95% confidence interval [CI] 1.67-2.30; p < 0.001) and all sub-components: need for renal replacement therapy (aOR 3.83; 95%CI 3.02-4.84), persistent renal dysfunction (aOR 1.72; 95%CI 1.40-2.12), and 30-day mortality (aOR 1.70; 95%CI 1.38-2.09), p all < 0.001. The sensitivity analysis showed an association of FA with MAKE30 independent from a pre-existing CKD, but exclusively in patients with AKI stage 3. Furthermore, FA was independently associated with the creatinine trajectory over the whole observation period.

CONCLUSIONS

Fluid accumulation is significantly associated with MAKE30 in critically ill patients. This association is independent from pre-existing CKD and strongest in patients with AKI stage 3.

ACETATE RINGER'S SOLUTION VERSUS NORMAL SALINE SOLUTION IN SEPSIS: A RANDOMIZED, CONTROLLED TRIAL

ABSTRACT

Background: Normal saline solution (NSS) and Ringer's acetate solution (RAS) are commonly given to critically ill patients as a fundamental fluid therapy. However, the effect of RAS and NSS on sepsis patient outcomes remains unknown. Methods: We conducted a single-center prospective open-label parallel controlled trial to enroll adult patients (>18 years old) diagnosed with sepsis. Participants received either RAS or NSS for intravenous infusion for 5 days. The primary outcome was the incidence of major adverse kidney events within 28 days (MAKE28). Secondary outcomes included 30-/90-day mortality, acute kidney injury, and hyperchloremia. The patients were then reclassified as NSS-only, RAS-only, and RAS + NSS groups according to the type of fluid they had received before enrollment. Thereafter, a secondary post hoc analysis was performed. Results: Two hundred fifty-five septic patients were screened, and 143 patients (51.0% in RAS group and 49.0% in NSS group) were enrolled in the study. Each group received a median of 2 L of fluid administration during five interventional days. Of the patients, 39.3% had received 500 mL (500-1,000 mL) of balanced salt solutions (BSSs) before intensive care unit (ICU) admission. There was no statistical difference among the RAS and NSS group on the primary outcome MAKE28 in the initial analysis (23.3% vs. 20.0%; OR, 1.2 [0.6 to 2.2]; P = 0.69). MAKE28 was observed in 23.3% of RAS-only versus 27.3% of NSS-only group patients (0.82 [0.35-1.94], P = 0.65) in the secondary post hoc analysis. The patients in the NSS-only group had a longer invasive mechanical ventilation days and a trend toward the accumulation of serum chloride. Conclusion: This study observed no statistically significant difference on MAKE28 and secondary outcomes among sepsis patients receiving RAS and NSS. However, it is unclear whether the large amount of fluid resuscitation before ICU admission and carrier NSS narrowed the difference between BSSs and NSSs.

Balanced crystalloids versus saline for critically ill patients (BEST-Living): a systematic review and individual patient data meta-analysis

BACKGROUND

The effect of balanced crystalloids compared with that of saline in critically ill patients overall and in specific subgroups is unclear. We aimed to assess whether use of balanced solutions, compared with 0·9% sodium chloride (saline), decreased in-hospital mortality in adult patients in intensive care units (ICUs).

METHODS

For this systematic review and individual patient data meta-analysis, we searched PubMed, Embase, and CENTRAL databases from inception until March 1, 2022 (updated Sept 1, 2023) for individually randomised and cluster-randomised trials comparing balanced solutions with saline for adult patients in the ICU. Eligible trials were those that allocated patients to receive balanced solutions or saline for fluid resuscitation and maintenance fluids, or for maintenance fluids only; and administered the allocated fluid throughout ICU admission or, for trials using landmark mortality as their primary outcome, until the timepoint at which mortality was assessed (if ≥28 days). Authors of eligible trials were contacted to request individual patient data. Data obtained from eligible trials were merged, checked for accuracy, and centrally analysed by use of Bayesian regression models. The primary outcome was in-hospital mortality. Prespecified subgroups included patients with traumatic brain injury. This study was registered with PROSPERO (CRD42022299282).

FINDINGS

Our search identified 5219 records, yielding six eligible randomised controlled trials. Data obtained for 34 685 participants from the six trials, 17 407 assigned to receive balanced crystalloids and 17 278 to receive saline, were included in the analysis. The mean age of participants was 58·8 years (SD 17·5). Of 34 653 participants with available data, 14 579 (42·1%) were female and 20 074 (57·9%) were male. Among patients who provided consent to report in-hospital mortality, 2907 (16·8%) of 17 313 assigned balanced solutions and 2975 (17·3%) of 17 166 assigned saline died in hospital (odds ratio [OR] 0·962 [95% CrI 0·909 to 1·019], absolute difference -0·4 percentage points [-1·5 to 0·2]). The posterior probability that balanced solutions reduced mortality was 0·895. In patients with traumatic brain injury, 191 (19·1%) of 999 assigned balanced and 141 (14·7%) of 962 assigned saline died (OR 1·424 [1·100 to 1·818], absolute difference 3·2 percentage points [0·7 to 8·7]). The probability that balanced solutions increased mortality in patients with traumatic brain injury was 0·975. In an independent risk of bias assessment, two trials were deemed to be at low risk of bias and four at high risk of bias.

INTERPRETATION

The probability that using balanced solutions in the ICU reduces in-hospital mortality is high, although the certainty of the evidence was moderate and the absolute risk reduction was small. In patients with traumatic brain injury, using balanced solutions was associated with increased in-hospital mortality.

FUNDING

HCor (Brazil) and The George Institute for Global Health (Australia).

Isotonic balanced fluid versus 0.9% saline in patients with moderate to severe traumatic brain injury: A double-blinded randomised controlled trial

BACKGROUND AND IMPORTANCE

Traumatic brain injury (TBI) is a global health concern with significant economic impact. Optimal fluid therapy aims to restore intravascular volume, maintain cerebral perfusion pressure and blood flow, thus preventing secondary brain injury. While 0.9% saline (NS) is commonly used, concerns about acid-base and electrolyte imbalance and development of acute kidney injury (AKI) lead to consideration of balanced fluids as an alternative.

OBJECTIVES

This study aimed to compare the outcomes of patients with moderate to severe TBI treated with Sterofundin (SF) versus NS.

DESIGN, SETTINGS AND PARTICIPANTS

A double-blinded randomised controlled trial of patients aged 18 to 65 years with TBI was conducted at the University Malaya Medical Centre from February 2017 to November 2019.

INTERVENTION OR EXPOSURE

Patients were randomly assigned to receive either NS or SF. The study fluids were administered for 72 h as continuous infusions or boluses. Participants, investigators, and staff were blinded to the fluid type.

OUTCOMES MEASURE AND ANALYSIS

The primary outcome was in-hospital mortality. Relative risk (RR) with 95% confidence interval (CI) was calculated.

MAIN RESULTS

A total of 70 patients were included in the analysis, with 38 in the NS group and 32 in the SF group. The in-hospital mortality rate were 3 (7.9%) in the NS group vs. 4 (12.5%) in the SF group, RR = 1.29 (95% CI, 0.64 to 2.59; p = 0.695). No patients developed AKI and required renal replacement therapy. ICP on day 3 was significantly higher in the SF group (18.60 ± 9.26) compared to 12.77 ± 3.63 in the NS group, (95% CI, -11.46 to 0.20; p = 0.037). There were no significant differences in 3-day biochemical parameters and cerebral perfusion pressure, ventilator-free days, length of ICU stay, or Glasgow Outcome Scale-Extended (GOS-E) score at 6 months.

CONCLUSIONS

In patients with moderate to severe TBI, the use of SF was not associated with reduced in-hospital mortality, development of AKI, or improved 6-month GOS-E when compared to NS.

Sepsis-associated acute kidney injury-treatment standard

Sepsis is a host's deleterious response to infection, which could lead to life-threatening organ dysfunction. Sepsis-associated acute kidney injury (SA-AKI) is the most frequent organ dysfunction and is associated with increased morbidity and mortality. Sepsis contributes to ≈50% of all AKI in critically ill adult patients. A growing body of evidence has unveiled key aspects of the clinical risk factors, pathobiology, response to treatment and elements of renal recovery that have advanced our ability to detect, prevent and treat SA-AKI. Despite these advancements, SA-AKI remains a critical clinical condition and a major health burden, and further studies are needed to diminish the short and long-term consequences of SA-AKI. We review the current treatment standards and discuss novel developments in the pathophysiology, diagnosis, outcome prediction and management of SA-AKI.

A Systematic Bibliometric Analysis of High-Impact Articles in Critical Care Nephrology

INTRODUCTION

Critical care nephrology is a subspecialty that merges critical care and nephrology in response to shared pathobiology, clinical care, and technological innovations. To date, there has been no description of the highest impact articles. Accordingly, we systematically identified high impact articles in critical care nephrology.

METHODS

This was a bibliometric analysis. The search was developed by a research librarian. Web of Science was searched for articles published between January 1, 2000 and December 31, 2020. Articles required a minimum of 30 citations, publication in English language, and reporting of primary (or secondary) original data. Articles were screened by two reviewers for eligibility and further adjudicated by three experts. The "Top 100" articles were hierarchically ranked by adjudication, citations in the 2 years following publication and journal impact factor (IF). For each article, we extracted detailed bibliometric data. Risk of bias was assessed for randomized trials by the Cochrane Risk of Bias tool. Analyses were descriptive.

RESULTS

The search yielded 2,805 articles. Following initial screening, 307 articles were selected for full review and adjudication. The Top 100 articles were published across 20 journals (median [IQR] IF 10.6 [8.9-56.3]), 38% were published in the 5 years ending in 2020 and 62% were open access. The agreement between adjudicators was excellent (intraclass correlation, 0.96; 95% CI, 0.84-0.99). Of the Top 100, 44% were randomized trials, 35% were observational, 14% were systematic reviews, 6% were nonrandomized interventional studies and one article was a consensus document. The risk of bias among randomized trials was low. Common subgroup themes were RRT (42%), AKI (30%), fluids/resuscitation (14%), pediatrics (10%), interventions (8%), and perioperative care (6%). The citations for the Top 100 articles were 175 (95-393) and 9 were cited >1,000 times.

CONCLUSION

Critical care nephrology has matured as an important subspecialty of critical care and nephrology. These high impact papers have focused largely on original studies, mostly clinical trials, within a few core themes. This list can be leveraged for curricula development, to stimulate research, and for quality assurance.

Resuscitation and Preparation of the Emergency General Surgery Patient

Traditionally, the workflow surrounding a general surgery patient allows for a period of evaluation and optimization of underlying medical issues to allow for risk modification; however, in the emergency, this optimization period is largely condensed because of its time-dependent nature. Because the lack of optimization can lead to complications, the ability to rapidly resuscitate the patient, proceed to procedural intervention to control the situation, and manage common medical comorbidities is paramount. This article provides an overview on these subjects.

Precision fluid and vasoactive drug therapy for critically ill patients

There are several clinical practice guidelines concerning the use of fluid and vasoactive drug therapies in critically ill adult patients, but the recommendations in these guidelines are often based on low-quality evidence. Further, some were compiled prior to the publication of landmark clinical trials, particularly in the comparison of balanced crystalloid and normal saline. An important consideration in the treatment of critically ill patients is the application of precision medicine to provide the most effective care to groups of patients most likely to benefit from the therapy. Although not currently widely integrated into these practice guidelines, the utility of precision medicine in critical illness is a recognized research priority for fluid and vasoactive therapy management. The purpose of this narrative review was to illustrate the evaluation and challenges of providing precision fluid and vasoactive therapies to adult critically ill patients. The review includes a discussion of important investigations published after the release of currently available clinical practice guidelines to provide insight into how recommendations and research priorities may change future guidelines and bedside care for critically ill patients.

Balanced crystalloid solutions versus normal saline in intensive care units: a systematic review and meta-analysis

BACKGROUND

Intravenous fluid therapy is important for pediatric and adult patients in intensive care units (ICUs). However, medical professionals continue to struggle to determine the most appropriate fluids to obtain the best possible outcomes for each patient.

OBJECTIVE

We conducted a meta-analysis involving cohort studies and randomized controlled trials (RCTs) to compare the influence of balanced crystalloid solutions and normal saline among patients in ICUs.

PATIENTS AND METHODS

Studies that compared balanced crystalloid solutions and saline in ICU patients from databases including PubMed, Embase, Web of Science, and Cochrane Library were systematically searched up to July 25, 2022. The primary outcomes were mortality and renal-related outcomes, which included major adverse kidney events within 30 days (MAKE30), acute kidney injury (AKI), new receipt of renal replacement therapy (RRT), maximum creatinine increasing, maximum creatinine level, and final creatinine level ≥ 200% of baseline. Service utilization including length of hospital stay, ICU stay, ICU-free days and ventilator-free days were also reported.

RESULTS

A total of 13 studies (10 RCTs and 3 cohort studies) involving 38,798 patients in ICUs met the selection criteria. Our analysis revealed that each subgroup had no significant difference in mortality outcomes among ICU patients between balanced crystalloid solutions and normal saline. A significant difference was detected between the adult groups (odds ratio [OR], 0.92; 95% confidence interval [CI], [0.86, 1.00]; p = 0.04) indicating that the AKI in the balanced crystalloid solutions group was lower than that in the normal saline group. Other renal-related outcomes, such as MAKE30, RRT, maximum creatinine increasing, maximum creatinine level, and final creatinine level ≥ 200% of baseline showed no significant difference between the two groups. Regarding secondary outcomes, the balanced crystalloid solution group had a longer ICU stay time (WMD, 0.02; 95% CI, [0.01, 0.03]; p = 0.0004 and I2 = 0%; p = 0.96) than the normal saline group among adult patients. Furthermore, children treated with balanced crystalloid solution had a shorter hospital stay time (WMD, - 1.10; 95% CI, [- 2.10, - 0.10]; p = 0.03 and I2 = 17%; p = 0.30) than those treated with saline.

CONCLUSIONS

Compared with saline, balanced crystalloid solutions could not reduce the risk of mortality and renal-related outcomes, including MAKE30, RRT, maximum creatinine increasing, maximum creatinine level, and final creatinine level ≥ 200% of baseline, but the solutions may reduce total AKI incidence among adult patients in ICUs. For service utilization outcomes, balanced crystalloid solutions were associated with a longer length of ICU stay in the adult group and shorter length of hospital stay in the pediatric group.

Comparison of Balanced Crystalloids versus Normal Saline in Critically Ill Patients: A Systematic Review with Meta-Analysis and Trial Sequential Analysis of Randomized Controlled Trials

Background

Fluid resuscitation is routinely needed for critically ill patients. However, the optimal choice between crystalloids and normal saline is in heat debate.

Objective

To conduct a meta-analysis comparing normal saline and balanced crystalloids in the treatment of critically ill patients with composite mortality as the primary outcome.

Methods

PubMed, Embase, Medline, Web of Science, and Cochrane Library were searched from inception up to March 2022. Studies of critically ill adult patients assigned to receive normal saline or balanced crystalloids were included. We conducted a meta-analysis using an inverse variance, random-effects model in addition to trial sequential analysis (TSA). The primary outcome was composite mortality. Subgroup analyses were also conducted.

Results

Eighteen full-text studies (n=36,224) were included. Balanced crystalloids were associated with lower mortality compared with normal saline (risk ratio [RR]=0.96; 95% confidential interval [CI] 0.93, 1; p=0.03; I2=0) and lower incidence of acute kidney injury/acute renal failure (RR =0.93; 95% CI = 0.87, 0.99; p=0.03). No significant difference was observed in other outcomes. In the sepsis patients, the balanced crystalloid showed a lower composite mortality rate compared with normal saline (RR =0.91; 95% CI = 0.85, 0.99; p=0.02). TSA analysis demonstrated that, with 80% power, the effect of balanced crystalloid is not larger than a 10% relative decrease in composite mortality compared with normal saline.

Conclusion and Relevance

This study demonstrated that balanced crystalloids could be an optimal choice over normal saline in critically ill patients to a reduced composite mortality rate. In patients with sepsis, the difference is especially significant. Nonetheless, the optimal resuscitation fluid option between saline and balanced crystalloid solutions should be investigated further with more evidence.

A Hospital-Wide Open-Label Cluster Crossover Pragmatic Comparative Effectiveness Randomized Trial Comparing Normal Saline to Ringer's Lactate: Protocol and Statistical Analysis Plan of The FLUID Trial

BACKGROUND

Normal saline (NS) and Ringer's lactate (RL) are the most common crystalloids given to hospitalized patients. Despite concern about possible harm associated with NS (eg, hyperchloremic metabolic acidosis, impaired kidney function, and death), few large multicenter randomized trials focused on critically ill patients have compared these fluids. Uncertainty exists about the effects of these fluids on clinically important outcomes across all hospitalized patients.

OBJECTIVE

The FLUID trial is a pragmatic, multicenter, 2×2 cluster crossover comparative effectiveness randomized trial that aims to evaluate the effectiveness of a hospital-wide policy that stocks either NS or RL as the main crystalloid fluid in 16 hospitals across Ontario, Canada.

METHODS

All hospitalized adult and pediatric patients (anticipated sample size 144,000 patients) with an incident admission to the hospital over the course of each study period will be included. Either NS or RL will be preferentially stocked throughout the hospital for 12 weeks before crossing to the alternate fluid for the subsequent 12 weeks. The primary outcome is a composite of death and hospital readmission within 90 days of hospitalization. Secondary outcomes include death, hospital readmission, dialysis, reoperation, postoperative reintubation, length of hospital stay, emergency department visits, and discharge to a facility other than home. All outcomes will be obtained from health administrative data, eliminating the need for individual case reports. The primary analysis will use cluster-level summaries to estimate cluster-average treatment effects.

RESULTS

The statistical analysis plan has been prepared "a priori" in advance of receipt of the trial data set from ICES and any analyses.

CONCLUSIONS

We describe the protocol and statistical analysis plan for the evaluation of primary and secondary outcomes for the FLUID trial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04512950; https://classic.clinicaltrials.gov/ct2/show/NCT04512950.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51783.

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.

Management of Sepsis and Septic Shock: What Have We Learned in the Last Two Decades?

Sepsis is a clinical syndrome encompassing physiologic and biological abnormalities caused by a dysregulated host response to infection. Sepsis progression into septic shock is associated with a dramatic increase in mortality, hence the importance of early identification and treatment. Over the last two decades, the definition of sepsis has evolved to improve early sepsis recognition and screening, standardize the terms used to describe sepsis and highlight its association with organ dysfunction and higher mortality. The early 2000s witnessed the birth of early goal-directed therapy (EGDT), which showed a dramatic reduction in mortality leading to its wide adoption, and the surviving sepsis campaign (SSC), which has been instrumental in developing and updating sepsis guidelines over the last 20 years. Outside of early fluid resuscitation and antibiotic therapy, sepsis management has transitioned to a less aggressive approach over the last few years, shying away from routine mixed venous oxygen saturation and central venous pressure monitoring and excessive fluids resuscitation, inotropes use, and red blood cell transfusions. Peripheral vasopressor use was deemed safe and is rising, and resuscitation with balanced crystalloids and a restrictive fluid strategy was explored. This review will address some of sepsis management's most important yet controversial components and summarize the available evidence from the last two decades.

Consensus Guidelines for Perioperative Care for Emergency Laparotomy Enhanced Recovery After Surgery (ERAS®) Society Recommendations Part 2-Emergency Laparotomy: Intra- and Postoperative Care

BACKGROUND

This is Part 2 of the first consensus guidelines for optimal care of patients undergoing emergency laparotomy (EL) using an Enhanced Recovery After Surgery (ERAS) approach. This paper addresses intra- and postoperative aspects of care.

METHODS

Experts in aspects of management of high-risk and emergency general surgical patients were invited to contribute by the International ERAS® Society. PubMed, Cochrane, Embase, and Medline database searches were performed for ERAS elements and relevant specific topics. Studies on each item were selected with particular attention to randomized clinical trials, systematic reviews, meta-analyses, and large cohort studies and reviewed and graded using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. Recommendations were made on the best level of evidence, or extrapolation from studies on elective patients when appropriate. A modified Delphi method was used to validate final recommendations. Some ERAS® components covered in other guideline papers are outlined only briefly, with the bulk of the text focusing on key areas pertaining specifically to EL.

RESULTS

Twenty-three components of intraoperative and postoperative care were defined. Consensus was reached after three rounds of a modified Delphi Process.

CONCLUSIONS

These guidelines are based on best available evidence for an ERAS® approach to patients undergoing EL. These guidelines are not exhaustive but pull together evidence on important components of care for this high-risk patient population. As much of the evidence is extrapolated from elective surgery or emergency general surgery (not specifically laparotomy), many of the components need further evaluation in future studies.

New Insights into the Fluid Management in Patients with Septic Shock

The importance of fluid resuscitation therapy during the early stages of sepsis management is a well-established principle. Current Surviving Sepsis Campaign (SSC) guidelines recommend the early administration of intravenous crystalloid fluids for sepsis-related hypotension or hyperlactatemia due to tissue hypoperfusion, within the first 3 h of resuscitation and suggest using balanced solutions (BSs) instead of normal saline (NS) for the management of patients with sepsis or septic shock. Studies comparing BS versus NS administration in septic patients have demonstrated that BSs are associated with better outcomes including decreased mortality. After initial resuscitation, fluid administration has to be judicious in order to avoid fluid overload, which has been associated with increased mortality, prolonged mechanical ventilation, and worsening of acute kidney injury. The "one size fits all" approach may be "convenient" but it should be avoided. Personalized fluid management, based on patient-specific hemodynamic indices, provides the foundations for better patient outcomes in the future. Although there is a consensus on the need for adequate fluid therapy in sepsis, the type, the amount of administered fluids, and the ideal fluid resuscitation strategy remain elusive. Well-designed large randomized controlled trials are certainly needed to compare fluid choices specifically in the septic patient, as there is currently limited evidence of low quality. This review aims to summarize the physiologic principles and current scientific evidence regarding fluid management in patients with sepsis, as well as to provide a comprehensive overview of the latest data on the optimal fluid administration strategy in sepsis.

INCREASE IN CHLORIDE IS ASSOCIATED WITH MAJOR ADVERSE KIDNEY EVENTS IN CRITICALLY ILL PATIENTS

ABSTRACT

Purpose: This study aimed to identify the association between hyperchloremia at intensive care unit (ICU) admission and/or the increase of blood chloride levels and the incidence of major adverse kidney events within 30 days (MAKE30) in critically ill adults. Methods: We conducted a retrospective study to analyze the data of all adult patients admitted to the ICU of a tertiary academic hospital in China between April 2020 and April 2022. Patients were categorized based on their admission chloride levels (hyperchloremia ≥110 mmol/L and nonhyperchloremia <110 mmol/L) and stratified on the increased chloride levels 48 h after ICU admission (∆Cl ≥5 mmol/L and ∆Cl <5 mmol/L). The primary outcome was the MAKE30 incidence, including in-hospital death, new receipt of renal replacement therapy (RRT), and persistent renal dysfunction (PRD). Association between hyperchloremia at ICU admission and/or the increase of chloride and the incidence of MAKE30 were assessed using logistic regression. Result: A total of 2,024 patients with a median age of 67 years (interquartile range [IQR], 55-76 years) and a median Acute Physiology and Chronic Health Evaluation II score of 22 (IQR, 17-28) were included. Hyperchloremia occurred in 30.9% (n = 625), and ΔCl ≥5 mmol/L occurred in 18.5% (n = 375) of all ICU patients. The overall MAKE30 incidence was 33.6% (n = 680), including a 10.9% of 30-day hospital mortality (n = 220; as well as overall in-hospital mortality, 11.8% [n = 238]), a 20.2% (n = 408) of PRD, and a 18.0% (n = 365) of new RRT. After adjusted for confounders, it was found that ΔCl ≥5 mmol/L (odds ratio [OR], 1.46; 95% confidence interval [CI], 1.096-1.93; P = 0.010), but not hyperchloremia (OR, 0.99; 95% CI, 0.77-1.28; P = 0.947), was associated with increased incidence of MAKE30. Conclusion: An increased chloride level in the first 48 h of ICU admission was an independent risk factor for MAKE30, whereas hyperchloremia at ICU admission was not associated with an increased incidence of MAKE30. Large-scale prospective studies are needed to verify our findings.

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.

FLUID trial: a hospital-wide open-label cluster cross-over pragmatic comparative effectiveness randomised pilot trial comparing normal saline to Ringer's lactate

OBJECTIVES

Normal saline (NS) and Ringer's lactate (RL) are the most common crystalloids used for fluid therapy. Despite evidence of possible harm associated with NS (eg, hyperchloremic metabolic acidosis, impaired kidney function and death), few large multi-centre randomised trials have evaluated the effect of these fluids on clinically important outcomes. We conducted a pilot trial to explore the feasibility of a large trial powered for clinically important outcomes.

DESIGN

FLUID was a pragmatic pilot cluster randomised cross-over trial.

SETTING

Four hospitals in the province of Ontario, Canada PARTICIPANTS: All hospitalised adult and paediatric patients with an incident admission to the hospital over the course of each study period.

INTERVENTIONS

A hospital wide policy/strategy which stocked either NS or RL throughout the hospital for 12 weeks before crossing over to the alternate fluid for the subsequent 12 weeks.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary feasibility outcome was study fluid protocol adherence. Secondary feasibility outcomes included time to Research Ethics Board (REB) approval and trial initiation. Primary (composite of death or re-admission to hospital in first 90 days of index hospitalisation) and secondary clinical outcomes were analysed descriptively.

RESULTS

Among 24 905 included patients, mean age 59.1 (SD 20.5); 13 977 (56.1%) were female and 21 150 (85.0%) had medical or surgical admitting diagnoses. Overall, 96 821 L were administered in the NS arm, and 78 348 L in the RL arm. Study fluid adherence to NS and RL was 93.7% (site range: 91.6%-98.0%) and 79.8% (site range: 72.5%-83.9%), respectively. Time to REB approval ranged from 2 to 48 days and readiness for trial initiation from 51 to 331 days. 5544 (22.3%) patients died or required hospital re-admission in the first 90 days.

CONCLUSIONS

The future large trial is feasible. Anticipating and addressing logistical challenges during the planning stages will be imperative.

TRIAL REGISTRATION NUMBER

NCT02721485.

Chloride, Sodium and Calcium Intake Are Associated with Mortality and Follow-Up Kidney Function in Critically Ill Patients Receiving Continuous Veno-Venous Hemodialysis-A Retrospective Study

BACKGROUND

Studies on the association between solute, nutrition and fluid intakes and mortality and later kidney function in critically ill acute kidney injury (AKI) patients receiving continuous veno-venous hemodialysis (CVVHD) are scarce.

METHODS

Altogether, 471 consecutive critically ill AKI patients receiving CVVHD in the research intensive care unit (ICU) were recruited in this single-center, retrospective study.

RESULTS

The median age was 66 (58-74) years, and 138 (29.3%) were female. The 90-day and one-year mortalities were 221 (46.9%) and 251 (53.3%), respectively. After adjusting for age, sex, Acute Physiology and Chronic Health Evaluation II (APACHE) score, coronary artery disease, immunosuppression, ICU care duration, mechanical ventilation requirement, vasopressor requirement and study time period, the cumulative daily intake of potassium, chloride, sodium, phosphate, calcium, glucose, lipids and water was associated with one-year mortality in separate multivariable cox proportional hazards models. In a sensitivity analysis excluding patients who died within the first three days of ICU care, the daily intake of chloride (hazard ratio (HR) 1.001, confidence interval (CI) 95% 1.000-1.003, p = 0.032), sodium (HR 1.001, CI 95% 1.000-1.002, p = 0.031) and calcium (HR 1.129, CI 95% 1.025-1.243, p = 0.014) remained independently associated with mortality within one-year in the respective, similarly adjusted multivariable cox analyses. The cumulative daily intake of chloride, sodium, calcium and water was independently associated with the estimated glomerular filtration rate (eGFR) at 90 days follow-up in separate substantially adjusted multivariable cox proportional hazards models.

CONCLUSION

The cumulative daily intake of chloride, sodium and calcium is associated with mortality and daily chloride, sodium, calcium and water intake is associated with follow-up eGFR in critically ill patients with CVVHD-treated AKI.

A retrospective analysis of normal saline and lactated ringers as resuscitation fluid in sepsis

Background

The Surviving Sepsis Campaign suggested preferential resuscitation with balanced crystalloids, such as Lactated Ringer's (LR), although the level of recommendation was weak, and the quality of evidence was low. Past studies reported an association of unbalanced solutions, such as normal saline (NS), with increased AKI risks, metabolic acidosis, and prolonged ICU stay, although some of the findings are conflicting. We have compared the outcomes with the preferential use of normal saline vs. ringer's lactate in a cohort of sepsis patients.

Method

We performed a retrospective cohort analysis of patients visiting the ED of 19 different Mayo Clinic sites between August 2018 to November 2020 with sepsis and receiving at least 30 mL/kg fluid in the first 6 h. Patients were divided into two cohorts based on the type of resuscitation fluid (LR vs. NS) and propensity-matching was done based on clinical characteristics as well as fluid amount (with 5 ml/kg). Single variable logistic regression (categorical outcomes) and Cox proportional hazards regression models were used to compare the primary and secondary outcomes between the 2 groups.

Results

Out of 2022 patients meeting our inclusion criteria; 1,428 (70.6%) received NS, and 594 (29.4%) received LR as the predominant fluid (>30 mL/kg). Patients receiving predominantly NS were more likely to be male and older in age. The LR cohort had a higher BMI, lactate level and incidence of septic shock. Propensity-matched analysis did not show a difference in 30-day and in-hospital mortality rate, mechanical ventilation, oxygen therapy, or CRRT requirement. We did observe longer hospital LOS in the LR group (median 5 vs. 4 days, p = 0.047 and higher requirement for ICU post-admission (OR: 0.70; 95% CI: 0.51-0.96; p = 0.026) in the NS group. However, these did not remain statistically significant after adjustment for multiple testing.

Conclusion

In our matched cohort, we did not show any statistically significant difference in mortality rates, hospital LOS, ICU admission after diagnosis, mechanical ventilation, oxygen therapy and RRT between sepsis patients receiving lactated ringers and normal saline as predominant resuscitation fluid. Further large-scale prospective studies are needed to solidify the current guidelines on the use of balanced crystalloids.

Machine-learning-derived sepsis bundle of care

PURPOSE

Compliance to the Surviving Sepsis Campaign (SSC) guidelines is limited. This is known to be associated with increased mortality. The aim of this retrospective cohort study was to identify among the SCC guidelines the optimal bundle of recommendations that minimize 28-day mortality.

METHODS

We used a training cohort to identify, using a least absolute shrinkage and selection operator penalized machine learning model, this bundle. Patients with sepsis/septic shock admitted to the intensive care unit (ICU) were extracted from two US databases, the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database (training and internal validation cohorts) and the eICU Collaborative Research Database (eICU-CRD) (external validation cohort). In the validation cohorts, we defined a bundle group that includes patients who were treated with at least all the recommendations selected in our bundle and a no-bundle group that includes patients in whom at least one recommendation from our bundle was omitted.

RESULTS

All-cause 28-day mortality was the primary outcome measure. A total of 42,735 patients were included. Six recommendations (antimicrobials, balanced crystalloid, insulin therapy, corticosteroids, vasopressin, and bicarbonate therapy) were identified from the training cohort to be included in our bundle. In the propensity score-(PS)-matched internal validation cohort, the bundle group was associated with a lower mortality (OR 0.41 [0.33-0.53]; p < 0.001) compared to the no-bundle group. This was confirmed in the PS-matched external validation cohort (OR 0.75 [0.60-0.94]; p 0.02).

CONCLUSION

Our bundle of six recommendations is associated with a dramatic reduction in mortality in sepsis and septic shock. This bundle needs to be evaluated prospectively.

Circulatory shock in adults in emergency department

Circulatory shock is a common condition that carries high morbidity and mortality. This review aims to update the critical steps in managing common types of shock in adult patients admitted to medical emergency and intensive care units. A literature review was performed by searching PubMed, EMBASE Ovid, and Cochrane Library, using the following search items: ("shock" OR "circulatory shock" OR "septic shock" OR "cardiogenic shock") AND ("management" OR "treatment" OR "resuscitation"). The review emphasizes prompt shock identification with tissue hypoperfusion, knowledge of the underlying pathophysiological mechanism, initial fluid resuscitation with balanced crystalloids, norepinephrine as the preferred vasopressor in septic and profound cardiogenic shock, and tailored intervention addressing specific etiologies. Point-of-care ultrasound may help evaluate an undifferentiated shock and determine fluid responsiveness. The approach to septic shock is improving; however, confirmatory studies are required for many existing (e.g., amount of initial fluids and steroids) and emerging (e.g., angiotensin II) therapies. Knowledge gaps and wide variations persist in managing cardiogenic shock that needs urgent addressing to improve outcomes.

Early Hyperchloremia and Outcomes After Severe Traumatic Brain Injury: Analysis of Resuscitation Outcomes Consortium Hypertonic Saline Trial

To investigate the effect of the occurrence of early hyperchloremia on death or severe disability at 180 days in patients with severe traumatic brain injury (TBI).

DESIGN

Post hoc analysis of Resuscitation Outcomes Consortium Hypertonic Saline (ROC HS)-TBI trial.

SETTING

A total of 114 North American emergency medical services agencies in the ROC.

PATIENTS

A total of 991 patients with severe TBI and Glasgow Coma Scale score of less than or equal to 8.

INTERVENTIONS

Prehospital resuscitation with single IV dose (250 cc) of 7.5% saline in 6% dextran-70, 7.5% saline (no dextran), or crystalloid.

MEASUREMENTS AND MAIN RESULTS

Patients with increased serum chloride concentrations (110 mmol/L or greater) 24 hours after randomization were identified. Hyperchloremia was graded into one or greater than or equal to 2 occurrences in the first 24 hours. Logistic regression analyses were performed to determine the effects of hyperchloremia on: 1) death or severe disability at 180 days and 2) death within 180 days after adjusting for confounders. Compared with patients without hyperchloremia, patients with greater than or equal to 2 occurrences of hyperchloremia had significantly higher odds of death or severe disability at 180 days (odds ratio [OR], 1.81; 95% CI, 1.19-2.75) and death within 180 days (OR, 1.89; 95% CI, 1.14-3.08) after adjustment for confounders. However, the total volume of fluids administered during the first 24 hours was an independent predictor of death within 180 days; therefore, after adding an interaction term between the total volume of fluids administered during the first 24 hours and greater than or equal to 2 occurrences of hyperchloremia, patients with greater than or equal to 2 occurrences of hyperchloremia had significantly higher odds of death within 180 days (OR, 2.35; 95% CI, 1.21-4.61 d) but not of composite outcome of death or severe disability at 180 days.

CONCLUSIONS

After modifying for the effect of the total volume of fluids administered during the first 24 hours, multiple occurrences of hyperchloremia in the first 24 hours were associated with higher odds of death within 180 days in patients with severe TBI.

Balanced Salt Solutions for Critically Ill Patients: Nonplused and Back to Basics

OBJECTIVES

The purpose of this article is to summarize the results of major randomized controlled trials (RCTs) comparing clinical outcomes of critically ill patients treated with normal saline (NS) or balanced salt solutions (BSSs), address discordant results of these studies, and provide direction for future investigations.

DATA SOURCES

PubMed (2011 to January 2022) with bibliographies of retrieved articles searched for additional articles.

STUDY SELECTION AND DATA EXTRACTION

RCTs comparing NS and BSSs in critically ill adult patients.

DATA SYNTHESIS

Recently published large RCTs comparing NS with BSSs in heterogeneous populations of intensive care unit patients did not find significant differences in mortality, despite positive findings in some end points in prior RCTs. However, there were a number of methodologic issues common to the RCTs including: varying study designs and end points, clinician discretion for the majority or all treatments other than the primary intervention fluid, heterogeneous patients with varying levels of acuity, and lack of power to investigate potential subgroup differences. In addition, there were problematic issues related to blinding and use of nonstudy fluids.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Intravenous fluids are a mainstay of supportive care for critically ill patients. Similar to the so-called crystalloid-colloid debate, there has been a long-standing debate among critical care clinicians and researchers concerning the preferred crystalloid solution, NS versus one of the available BSSs.

CONCLUSIONS

Despite the recent publication of large multicenter RCTs, the preferred resuscitation fluid, NS or a BSS, for critically ill patients is still open for debate, although the available investigations do provide some direction for clinicians and for future investigations.

Intravenous fluid therapy in sepsis

Sepsis is the dysregulated immune response to severe infection that is common and lethal among critically ill patients. Fluid administration is a common treatment for hypotension and shock in early sepsis. Fluid therapy can also cause edema and organ dysfunction. Research on the best treatment strategies for sepsis has provided insights on the optimal timing, dose, and type of fluid to treat patients with sepsis. Initial research on early goal-directed therapy for sepsis included an initial bolus of 30 ml/kg of fluid, but more recent research has supported use of smaller volumes. After initial fluid resuscitation, minimizing additional fluid administration may be beneficial, but no single measure has been established as the best method to guide ongoing fluid management in sepsis. Dynamic measures of "fluid responsiveness" can predict which patients will experience an increase in cardiac output from a fluid bolus. Use of such a measure in clinical care remains limited by applicability to patient populations and uncertainty regarding the effect on clinical outcomes. Recent research informs the effect of fluid composition on outcomes for patients with sepsis. Current data support the use of balanced crystalloids, rather than saline, and the use of crystalloids, rather than semisynthetic colloids. The role for albumin administration in sepsis remains uncertain. Future research should focus on determining the optimal volume of fluid during sepsis resuscitation, the effectiveness of measures of "fluid responsiveness" in improving outcomes, the optimal composition of crystalloid solutions, the role of albumin, and the effects of "deresuscitation" after septic shock.

Advances in Sepsis Care

This review article summarizes current scientific evidence regarding the treatment of sepsis. We highlight recent advances in sepsis management with a focus on antibiotics, fluids, vasopressors, and adjunctive therapies such as corticosteroids and renal replacement therapy.

Balanced Crystalloid versus Saline in Adults with Traumatic Brain Injury: Secondary Analysis of a Clinical Trial

Balanced crystalloids may improve outcomes compared with saline for some critically ill adults. Lower tonicity of balanced crystalloids could worsen cerebral edema in patients with intracranial pathology. The effect of balanced crystalloids versus saline on clinical outcomes in patients with traumatic brain injury (TBI) requires further study. We planned an a priori subgroup analysis of TBI patients enrolled in the pragmatic, cluster-randomized, multiple-crossover Isotonic Solutions and Major Adverse Renal Events Trial (SMART) (ClinicalTrials.gov: NCT02444988, NCT02547779). Primary outcome was 30-day in-hospital mortality. Secondary outcomes included hospital discharge disposition (home, facility, death). Regression models adjusted for pre-specified baseline covariates compared outcomes. TBI patients assigned to balanced crystalloids (n = 588) and saline (n = 569) had similar baseline characteristics including Injury Severity Score 19 (10); mean maximum head/neck Abbreviated Injury Score, 3.4 (1.0). Isotonic crystalloid volume administered between intensive care unit admission and first of hospital discharge or 30 days was 2037 (3470) mL and 1723 (2923) mL in the balanced crystalloids and saline groups, respectively (p = 0.18). During the study period, 94 (16%) and 82 (14%) patients (16%) died in the balanced crystalloid and saline groups, respectively (adjusted odds ratio [aOR], 1.03; 95% confidence interval [CI], 0.60 to 1.75; p = 0.913). Patients in the balanced crystalloid group were more likely to die or be discharged to another medical facility (aOR 1.38 [1.02-1.86]; p = 0.04). Overall, balanced crystalloids were associated with worse discharge disposition in critically injured patients with TBI compared with saline. The confidence intervals cannot exclude a clinically relevant increase in mortality when balanced crystalloids are used for patients with TBI.

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.

Intravenous maintenance fluid therapy practice in the pediatric acute and critical care settings: a European and Middle Eastern survey

The ideal fluid for intravenous maintenance fluid therapy (IV-MFT) in acutely and critically ill children is controversial, and evidence-based clinical practice guidelines are lacking and current prescribing practices remain unknown. We aimed to describe the current practices in prescribing IV-MFT in the context of acute and critically ill children with regard to the amount, tonicity, composition, use of balanced fluids, and prescribing strategies in various clinical contexts. A cross-sectional electronic 27-item survey was emailed in April-May 2021 to pediatric critical care physicians across European and Middle East countries. The survey instrument was developed by an expert multi-professional panel within the European Society of Pediatric and Neonatal Intensive Care (ESPNIC). A total of 154 respondents from 35 European and Middle East countries participated (response rate 64%). Respondents were physicians in charge of acute or critically ill children. All respondents indicated they routinely use a predefined formula to prescribe the amount of IV-MFT and considered fluid balance monitoring very important in the management of acute and critically ill children. The use of balanced solution was preferred if there were altered serum sodium and chloride levels or metabolic acidosis. Just under half (42%, 65/153) of respondents believed balanced solutions should always be used. Respondents considered the use of isotonic IV solutions as important for acute and critically ill children. In terms of the indication and the composition of IV-MFT prescribed, responses were heterogeneous among centers. Almost 70% (107/154) respondents believed there was a gap between current practice and what they considered ideal IV-MFT due to a lack of guidelines and inadequate training of healthcare professionals.   Conclusions: Our study showed considerable variability in clinical prescribing practice of IV-MFT in acute pediatric settings across Europe and the Middle East. There is an urgent need to develop evidence-based guidelines for IV-MFT prescription in acute and critically ill children. What is Known: • The administration of maintenance intravenous fluid therapy is a standard of care for a lot of hospitalized children • Maintenance intravenous fluid therapy prescriptions are often based on Holliday and Segar's historical guidelines even if this practice has been associated with several complications. What is New: • This study provided information on the prescribing practice regarding fluid restriction, fluid tonicity, and balance. • This study showed considerable variability in clinical prescribing practice of intravenous maintenance fluid therapy across Europe and the Middle East.

Use of pragmatic and explanatory trial designs in acute care research: lessons from COVID-19

Unique challenges arise when conducting trials to evaluate therapies already in common clinical use, including difficulty enrolling patients owing to widespread open-label use of trial therapies and the need for large sample sizes to detect small but clinically meaningful treatment effects. Despite numerous successes in trials evaluating novel interventions such as vaccines, traditional explanatory trials have struggled to provide definitive answers to time-sensitive questions for acutely ill patients with COVID-19. Pragmatic trials, which can increase efficiency by allowing some or all trial procedures to be embedded into clinical care, are increasingly proposed as a means to evaluate therapies that are in common clinical use. In this Personal View, we use two concurrently conducted COVID-19 trials of hydroxychloroquine (the US ORCHID trial and the UK RECOVERY trial) to contrast the effects of explanatory and pragmatic trial designs on trial conduct, trial results, and the care of patients managed outside of clinical trials. In view of the potential advantages and disadvantages of explanatory and pragmatic trial designs, we make recommendations for their optimal use in the evaluation of therapies in the acute care setting.

Protocol for balanced versus saline trialists: living systematic review and individual patient data meta-analysis of randomised controlled trials (BEST-Living study)

Objective: It remains unclear whether balanced solutions improve patient-centred outcomes in critically ill patients overall and whether the treatment effect is heterogeneous, with evidence that some populations of patients may be helped and others harmed. To provide the most up-to-date and comprehensive assessment of the totality of the evidence, we will perform an ongoing living systematic review with aggregated and individual patient data meta-analysis (IPDMA) comparing the use of balanced solutions with saline in critically ill adults. Design: Living systematic review using aggregated and individual patient data from randomised controlled trials. Data sources: We will conduct annual searches of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials. gov, the Australian New Zealand Clinical Trials Registry (ANZCTR), Japan's University Hospital Medical Information Network (UMIN) Center, and the Brazilian Registry of Clinical Trials (ReBEC). The first search was completed on 1 March 2022 and will be repeated annually. Authors of eligible trials will be invited to provide individual data for the IPDMA. The initial analysis will use all data received up to 30 June 2022. Review methods: We will include randomised controlled trials in adults treated in an intensive care unit that allocated individuals or clusters of patients to a balanced crystalloid solution or 0.9% saline for intravenous fluid therapy. Studies that used colloids as part of the intervention or that recruited only elective surgical patients will be excluded. The primary endpoint will be in-hospital mortality. The key secondary endpoint will be survival at longest follow-up for each trial. Data will be synthesised using both a random effect Bayesian meta-analysis and using hierarchical Bayesian models for individual patient data. Discussion: The use of balanced crystalloid solutions may reduce mortality and improve other outcomes in some critically ill patients. We will assess the totality of current and future evidence by performing an ongoing living systematic review with aggregated data and IPDMA. Protocol registration: CRD42022299282.

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.

The Efficacy and Safety of Sodium Bicarbonate Ringer's Solution in Critically Ill Patients: A Retrospective Cohort Study

Background: Sodium bicarbonate Ringer’s solution has been widely used in clinical practice in recent years. There are few clinical studies on the efficacy and safety of this fluid among critically ill patients until now.

Method: This retrospective cohort study included critically ill adult patients in the intensive care unit (ICU) of Tongji Hospital from 1 January 2019 to 31 December 2020. By reviewing exclusively the use of either sodium bicarbonate Ringer’s solution or saline for resuscitation or maintenance, the patients were included into two groups, respectively. The primary outcome was the major adverse kidney event within 30 days (MAKE30), including death, new receipt of renal replacement therapy, or persistent renal dysfunction. Safety outcomes were focused on arterial blood gas and plasma biochemical alterations, which might potentially be induced by the administration of bicarbonate Ringer’s solution.

Result: A total of 662 patients were included in the cohort. Compared to the saline group, the bicarbonate Ringer’s group had a significantly lower rate of the new receipt of renal replacement therapy [adjusted odds ratio (OR) = 0.591, 95% confidence interval (CI), 0.406 to 0.861; p = 0.006]. There was no significant difference between the two groups in 30-day mortality, final creatinine level ≥200% of baseline, and major adverse kidney event within 30 days. In subgroup analysis, the incidence of MAKE30 was higher in the bicarbonate Ringer’s group than that of the saline group among patients with cardiovascular disease. The patients in the bicarbonate Ringer’s group had a longer length of intensive care unit stay than patients in the saline group, but their new renal replacement therapy days were shorter. No major alterations were found in arterial blood gas and plasma biochemical during the follow-up period.

Conclusion: Compared to saline, sodium bicarbonate Ringer’s solution exhibited a potential renal function protective effect while causing no major alterations in arterial blood gas and plasma biochemistry. However, the application in patients with cardiovascular disease diagnosis at ICU admission should be cautious.

Fluid resuscitation with balanced crystalloids versus normal saline in critically ill patients: a systematic review and meta-analysis

Background

Intravenous fluids are used commonly for almost all intensive care unit (ICU) patients, especially for patients in need of resuscitation. The selection and use of resuscitation fluids may affect the outcomes of patients; however, the optimal resuscitative fluid remains controversial.

Methods

We systematically searched PubMed, Embase, and CENTRAL. Studies comparing balanced crystalloids and normal saline in ICU patients were selected. We used the Cochrane Collaboration tool to assess the risk of bias in studies. The primary outcome was mortality at the longest follow-up. Secondary outcomes included the incidence of acute kidney injury (AKI) and new renal replacement therapy (RRT).

Results

A total of 35,456 patients from eight studies were included. There was no significant difference between balanced crystalloid solutions and saline in mortality (risk ratio [RR]: 0.96; 95% confidence interval [CI]:0.92–1.01). The subgroup analysis with traumatic brain injury (TBI) showed lower mortality in patients receiving normal saline (RR:1.25; 95% CI 1.02–1.54). However, in patients with non-TBI, balanced crystalloid solutions achieved lower mortality than normal saline (RR: 0.94; 95% CI 0.90–0.99). There was no significant difference in moderate to severe AKI (RR: 0.96; 95% CI 0.90–1.01) or new RRT (RR: 0.94; 95% CI 0.84–1.04).

Conclusions

Compared with normal saline, balanced crystalloids may not improve the outcomes of mortality, the incidence of AKI, and the use of RRT for critically ill patients. However, balanced crystalloids reduce the risk of death in patients with non-TBI but increase the risk of death in those with TBI. Large-scale rigorous randomized trials with better designs are needed, especially for specific patient populations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13049-022-01015-3.

Balanced Crystalloids versus Normal Saline in Adults with Sepsis: A Comprehensive Systematic Review and Meta-Analysis

The crystalloid fluid of choice in sepsis remains debatable. We aimed to perform a comprehensive meta-analysis to compare the effect of balanced crystalloids (BC) vs. normal saline (NS) in adults with sepsis. A systematic search of PubMed, EMBASE, and Web of Sciences databases through 22 January 2022, was performed for studies that compared BC vs. NS in adults with sepsis. Our outcomes included mortality and acute kidney injury (AKI), need for renal replacement therapy (RRT), and ICU length of stay (LOS). Pooled risk ratio (RR) and mean difference (MD) with the corresponding 95% confidence intervals (CIs) were obtained using a random-effect model. Fifteen studies involving 20,329 patients were included. Overall, BC showed a significant reduction in the overall mortality (RR 0.88, 95% CI 0.81-0.96), 28/30-day mortality (RR 0.87, 95% CI 0.79-0.95), and AKI (RR 0.85, 95% CI 0.77-0.93) but similar 90-day mortality (RR 0.96, 95% CI 0.90-1.03), need for RRT (RR 0.91, 95% CI 0.76-1.08), and ICU LOS (MD -0.25 days, 95% CI -3.44, 2.95), were observed between the two groups. However, subgroup analysis of randomized controlled trials (RCTs) showed no statistically significant differences in overall mortality (RR 0.92, 95% CI 0.82-1.02), AKI (RR 0.71, 95% CI 0.47-1.06), and need for RRT (RR 0.71, 95% CI 0.36-1.41). Our meta-analysis demonstrates that overall BC was associated with reduced mortality and AKI in sepsis compared to NS among patients with sepsis. However, subgroup analysis of RCTs showed no significant differences in both overall mortality and AKI between the groups. There was no significant difference in the need for RRT or ICU LOS between BC and NS. Pending further data, our study supports using BC over NS for fluid resuscitation in adults with sepsis. Further large-scale RCTs are necessary to validate our findings.

Balanced Crystalloids versus Saline in Critically Ill Adults - A Systematic Review with Meta-Analysis

BACKGROUND: The comparative efficacy and safety of balanced crystalloid solutions and saline for fluid therapy in critically ill adults remain uncertain. METHODS: We systematically reviewed randomized clinical trials (RCTs) comparing the use of balanced crystalloids with saline in critically ill adults. The primary outcome was 90-day mortality after pooling data from low-risk-of-bias trials using a random-effects model. We also performed a Bayesian meta-analysis to describe the primary treatment effect in probability terms. Secondary outcomes included the incidence of acute kidney injury (AKI), new treatment with renal replacement therapy (RRT), and ventilator-free and vasopressor-free days to day 28. RESULTS: We identified 13 RCTs, comprising 35,884 participants. From six trials (34,450 participants) with a low risk of bias, the risk ratio (RR) for 90-day mortality with balanced crystalloids versus saline was 0.96 (95% confidence interval [CI], 0.91 to 1.01; I2 = 12.1%); using vague priors, the posterior probability that balanced crystalloids reduce mortality was 89.5%. The RRs of developing AKI and of being treated with RRT with balanced crystalloids versus saline were 0.96 (95% CI, 0.89 to 1.02) and 0.95 (95% CI, 0.81 to 1.11), respectively. Ventilator-free days (mean difference, 0.18 days; 95% CI, −0.45 to 0.81) and vasopressor-free days (mean difference, 0.19 days; 95% CI, −0.14 to 0.51) were similar between groups. CONCLUSIONS: The estimated effect of using balanced crystalloids versus saline in critically ill adults ranges from a 9% relative reduction to a 1% relative increase in the risk of death, with a high probability that the average effect of using balanced crystalloids is to reduce mortality. (PROSPERO number, CRD42021243399.)

Major adverse kidney events within 30 days in patients with acute pancreatitis: a tertiary-center cohort study

BACKGROUND

To evaluate the event rate of major adverse kidney events within 30 days (MAKE30) in acute pancreatitis (AP) and its potential risk factors.

METHODS

A retrospective analysis of a tertiary center data on all AP patients admitted within 72 h after onset of abdominal pain between June 2015 and June 2019 was conducted. MAKE30 - a composite of death, new renal replacement therapy (RRT), or persistent renal dysfunction (PRD) - and its individual components were retrieved at discharge or 30 days. Logistic regression analysis was used to assess the risk factors for MAKE30.

RESULTS

295 patients were enrolled and 16% experienced MAKE30. For individual components, the incidence was 3% for death, 15% for new RRT, and 5% for PRD. In multivariate logistic regression analysis, hyperchloremia at admission [OR = 8.38 (1.07-65.64); P = 0.043] and SOFA score [OR 1.63 (1.18-2.26); P = 0.003] were independent risk factors in predicting MAKE30. Further analysis showed that patients with hyperchloremia had more requirements of RRT (57% vs. 10%, P < 0.001), more PRD (14% vs. 4%, P = 0.034).

CONCLUSION

MAKE30 is a common event in AP patients. Hyperchloremia and SOFA score at admission were two independent risk factors for MAKE30.