Restricted fluid resuscitation in suspected sepsis associated hypotension (REFRESH): a pilot randomised controlled trial

Mean arterial pressure at the initiation of continuous renal replacement therapy as a prognostic indicator in patients with acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is a common complication in critically ill patients, with approximately 5% requiring continuous renal replacement therapy (CRRT). This study investigated the relationship between mean arterial pressure (MAP) and 28- and 90-day mortality in critically ill AKI patients treated with CRRT.

METHODS

This secondary analysis of a bicenter, retrospective, observational study included patients with AKI who were treated with CRRT from January 2009 to September 2016. Mortality at 28 and 90 days post-CRRT initiation was analyzed using multivariate regression, generalized additive models, smooth curve fitting, and sensitivity analyses.

RESULTS

A total of 1,142 patients were included, with 28-day and 90-day mortality rates of 62.1% and 71.8%, respectively. In multivariable-adjusted Cox models, MAP was inversely correlated with the risk of 28-day and 90-day mortality after adjusting for covariates. Hazard ratios (HRs) were calculated per 1 mmHg increment of MAP: adjusted HR for 28-day mortality 0.985 (p < 0.00001) and for 90-day mortality 0.987 (p = 0.00002). The adjusted HRs for 28-day and 90-day mortality in patients in the highest tertile of MAP compared with those in the lowest tertile were 0.682 (95% CI 0.543-0.857) and 0.730 (95% CI 0.592-0.899), respectively. Patients were grouped using MAP thresholds of <65 mmHg, 65-71.85 mmHg, and ≥71.85 mmHg, with similar results observed. Sensitivity analyses confirmed the inverse relationship between higher MAP before CRRT and lower mortality.

CONCLUSION

The higher the MAP before CRRT is, the lower the 28- and 90-day mortality of critically ill patients with AKI who are treated with CRRT.

Early norepinephrine for patients with septic shock: an updated systematic review and meta-analysis with trial sequential analysis

BACKGROUND

The optimal timing for initiating norepinephrine in septic shock is debated. This updated systematic review and meta-analysis aimed to evaluate the impact of early versus delayed norepinephrine initiation on mortality and clinical outcomes in adults with septic shock.

METHODS

A systematic search in Pubmed, EMbase and the Cochrane Library to identify eligible randomized controlled trials, propensity score matching (PSM) and observational studies that compare early norepinephrine initiation with non-early norepinephrine initiation in patients with acute circulatory failure. The primary outcome was mortality in intensive care unit. Secondary outcomes included intensive care unit length of stay, fluid volume received at 6 h, norepinephrine dose, mechanical ventilation-free days, renal replacement therapy free days, and time to achieve a targeted mean arterial pressure (MAP). Meta-analysis and subgroup analysis were conducted to calculate odds ratio (OR) or mean difference with 95% confidence interval (95%CI) using random-effect model. Trial sequential analysis was conducted to evaluate the conclusiveness of evidence.

RESULTS

Ten studies (two RCT, three PSM and five observational studies) involving 4767 patients were included. Early norepinephrine significantly reduced mortality in RCT (OR 0.49, 95%CI 0.25-0.96; I2 = 45%, p = 0.04), pooled RCT and PSM (OR 0.65, 95%CI 0.42-0.99; I2 = 74%, p = 0.05), and observational studies (OR 0.71, 95%CI 0.54-0.94; I2 = 66%). The trial sequential analysis indicated more data are needed. Subgroup analyses showed reduced mortality with early norepinephrine when lactate was ≤ 3mmol/L and administered within 1 h. Secondary outcomes showed a reduced fluid volume at 6h (RCT + PSM: mean difference -502 mL, 95%CI -899 to -106; I2 = 91%, p = 0.01), faster MAP target achievement (RCT + PSM: mean difference -1.30h, 95%CI -1.75 to -0.85; I2 = 0%, p < 0.01), more mechanical ventilation-free days (RCT + PSM: mean difference 3.99 days, 95%CI 2.42-5.57; I2 = 32%, p < 0.01) and smaller cumulative norepinephrine dose (Observational: mean difference -3.44 mcg/kg, 95%CI -6.13 to -0.76; I2 = 0%, p = 0.01) in the early initiation group compare to the non-early initiation group.

CONCLUSION

Early norepinephrine introduction in septic shock is associated with reduced mortality, decreased fluid volume administered at 6 h, faster time to achieve MAP target and more mechanical ventilation-free days. However, the trial sequential analysis indicates that further RCT are still needed to confirm these findings.

Emergency medicine updates: Management of sepsis and septic shock

INTRODUCTION

Sepsis is a common condition associated with significant morbidity and mortality. Emergency physicians play a key role in the diagnosis and management of this condition.

OBJECTIVE

This paper evaluates key evidence-based updates concerning the management of sepsis and septic shock for the emergency clinician.

DISCUSSION

Sepsis is a life-threatening syndrome, and rapid diagnosis and management are essential. Antimicrobials should be administered as soon as possible, as delays are associated with increased mortality. Resuscitation targets include mean arterial pressure ≥ 65 mmHg, mental status, capillary refill time, lactate, and urine output. Intravenous fluid resuscitation plays an integral role in those who are fluid responsive. Balanced crystalloids and normal saline are both reasonable options for resuscitation. Early vasopressors should be initiated in those who are not fluid-responsive. Norepinephrine is the recommended first-line vasopressor, and if hypotension persists, vasopressin should be considered, followed by epinephrine. Administration of vasopressors through a peripheral 20-gauge or larger intravenous line is safe and effective. Steroids such as hydrocortisone and fludrocortisone should be considered in those with refractory septic shock.

CONCLUSION

An understanding of the recent updates in the literature concerning sepsis and septic shock can assist emergency clinicians and improve the care of these patients.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2024

The 2024 revised edition of the Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock (J-SSCG 2024) is published by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine. This is the fourth revision since the first edition was published in 2012. The purpose of the guidelines is to assist healthcare providers in making appropriate decisions in the treatment of sepsis and septic shock, leading to improved patient outcomes. We aimed to create guidelines that are easy to understand and use for physicians who recognize sepsis and provide initial management, specialized physicians who take over the treatment, and multidisciplinary healthcare providers, including nurses, physical therapists, clinical engineers, and pharmacists. The J-SSCG 2024 covers the following nine areas: diagnosis of sepsis and source control, antimicrobial therapy, initial resuscitation, blood purification, disseminated intravascular coagulation, adjunctive therapy, post-intensive care syndrome, patient and family care, and pediatrics. In these areas, we extracted 78 important clinical issues. The GRADE (Grading of Recommendations Assessment, Development and Evaluation) method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 42 GRADE-based recommendations, 7 good practice statements, and 22 information-to-background questions were created as responses to clinical questions. We also described 12 future research questions.

European Society of Intensive Care Medicine (ESICM) 2025 clinical practice guideline on fluid therapy in adult critically ill patients: part 2-the volume of resuscitation fluids

OBJECTIVE

This European Society of Intensive Care Medicine (ESICM) guideline provides evidence-based recommendations on the volume of early resuscitation fluid for adult critically ill patients.

METHODS

An international panel of experts developed the guideline, focusing on fluid resuscitation volume in adult critically ill patients with circulatory failure. Using the PICO format, questions were formulated, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was applied to assess evidence and formulate recommendations.

RESULTS

In adults with sepsis or septic shock, the guideline suggests administering up to 30 ml/kg of intravenous crystalloids in the initial phase, with adjustments based on clinical context and frequent reassessments (very low certainty of evidence). We suggest using an individualized approach in the optimization phase (very low certainty of evidence). No recommendation could be made for or against restrictive or liberal fluid strategies in the optimization phase (moderate certainty of no effect). For hemorrhagic shock, a restrictive fluid strategy is suggested after blunt trauma (moderate certainty) and penetrating trauma (low certainty), with fluid administration for non-traumatic hemorrhagic shock guided by hemodynamic and biochemical parameters (ungraded best practice). For circulatory failure due to left-sided cardiogenic shock, fluid resuscitation as the primary treatment is not recommended. Fluids should be administered cautiously for cardiac tamponade until definitive treatment and guided by surrogate markers of right heart congestion in acute pulmonary embolism (ungraded best practice). No recommendation could be made for circulatory failure associated with acute respiratory distress syndrome.

CONCLUSIONS

The panel made four conditional recommendations and four ungraded best practice statements. No recommendations were made for two questions. Knowledge gaps were identified, and suggestions for future research were provided.

PREDICTING SEPSIS-INDUCED HYPOTENSION PATIENT ATTRIBUTES FOR RESTRICTIVE VERSUS LIBERAL FLUID STRATEGY

ABSTRACT

Background : Patients with sepsis-induced hypotension are generally treated with a combination of intravenous fluids and vasopressors. The attributes of patients receiving a liberal compared to a restrictive fluid strategy have not been fully characterized. We use machine learning (ML) techniques to identify key predictors of restrictive versus liberal fluids strategy, and the likelihood of receiving each strategy in distinct patient phenotypes. Methods: We performed a retrospective observational study of patients at Emory University Hospital from 2014 to 2021 that were hypotensive, met Sepsis-3 criteria, and received at least 1 L of intravenous crystalloid fluids. We excluded patients with nonseptic etiologies of hypotension. Supervised ML techniques were used to identify key predictors for the two strategies. Additionally, subset analyses were performed on patients with pneumonia, congestive heart failure (CHF), or chronic kidney disease (CKD). Using unsupervised ML techniques, we also identified three distinct sepsis-induced hypotension phenotypes and evaluated their likelihood of receiving either strategy. Results: We identified N = 15,292 patients and randomly split them into training (n = 12,233) and validation (n = 3,059) datasets. XGBoost was the most accurate model (AUC: 0.84) for predicting the strategies. While worse oxygenation was the strongest predictor of utilizing a restrictive fluid strategy, top predictors of a liberal fluid strategy included higher pulse and blood urea nitrogen. In subset analyses, CHF, CKD, and pneumonia were predictive of restrictive fluid strategy. We identified three distinct sepsis-induced hypotension phenotypes: 1) mild organ injury, 2) severe hypoxemia, and 3) renal dysfunction. Conclusions: We identified key predictors of restrictive versus liberal fluids strategy and distinct patient phenotypes for sepsis-induced hypotension.

Effect of restrictive fluid resuscitation on severe acute kidney injury in septic shock: a systematic review and meta-analysis

OBJECTIVES

Sepsis-associated hypotension or shock is a critical stage of sepsis, and a current clinical emergency that has high mortality and multiple complications. A new restrictive fluid resuscitation therapy has been applied, and its influence on patients' renal function remains unclear. The purpose of this study is to evaluate the influence of restrictive fluid resuscitation on incidence of severe acute kidney injury (AKI) in adult patients with sepsis hypotension and shock compared with usual care.

DESIGN

Systematic review and meta-analysis using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach.

DATA SOURCES

PubMed, Embase, Web of Science and Cochrane Library were searched through 1 November 2024.

ELIGIBILITY CRITERIA

We included randomised controlled trials that compared restrictive fluid resuscitation with liberal fluid therapy on patients with sepsis-associated hypotension and shock, to find out their effect on the incidence of severe AKI. Severe AKI was defined as the AKI network score 2-3 or Kidney Disease Improving Global Outcomes stages 2 and 3.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers used standardised methods to search, screen and code included trials. Risk of bias was assessed using the Cochrane Systematic Review Handbook for randomised clinical trials. Meta-analysis was conducted using random effects models. Sensitivity and subgroup analyses, trial sequential analysis (TSA), Egger's test and the trim-and-fill method were performed. Findings were summarised in GRADE evidence profiles and synthesised qualitatively.

RESULTS

Nine trials (3718 participants) were included in this research and the analysis was conducted in random effects model. There was a significant difference in the incidence of severe AKI (risk ratio 0.87, 95% CI 0.79 to 0.96, p=0.006; I2=0%) and the duration of mechanical ventilation (mean difference -41.14, 95% CI -68.80 to -13.48; p=0.004; I2=74%) between patients receiving restrictive fluid resuscitation and patients receiving liberal fluid resuscitation. TSA showed that the cumulative amount of participants met the required information size, the positive conclusion had been confirmed. The GRADE assessment results demonstrated moderate confidence in the incidence of severe AKI, as well as the results of all second outcomes except the Intensive Care Unit length of stay (ICU LOS), which received limited confidence. The result of incidence of worse AKI was rated as of high certainty.

CONCLUSIONS

It is conclusive that fluid restriction strategy is superior to usual care when it comes to reducing the incidence of severe AKI in sepsis-associated hypotension and shock. Shorter duration of ventilation is concerned with fluid restriction as well, but the heterogeneity is substantial. GRADE assessments confirmed moderate and above certainty. Traditional fluid resuscitation therapy has the potential to be further explored for improvements to be more precise and appropriate for a better prognosis.

PROSPERO REGISTRATION NUMBER

CRD42023449239.

Comparison of Early and Late Norepinephrine Administration in Patients With Septic Shock: A Systematic Review and Meta-Analysis

BACKGROUND

Vasopressor administration at an appropriate time is crucial, but the optimal timing remains controversial.

RESEARCH QUESTION

Does early vs late norepinephrine administration impact the prognosis of septic shock?

STUDY DESIGN AND METHODS

Searches were conducted in PubMed, EMBASE, the Cochrane Library, and KMbase databases. We included studies of adults with sepsis and categorized patients into an early and late norepinephrine group according to specific time points or differences in norepinephrine use protocols. The primary outcome was overall mortality. The secondary outcomes included length of stay in the ICU, days free from ventilator use, days free from renal replacement therapy, days free from vasopressor use, adverse events, and total fluid volume.

RESULTS

Twelve studies (four randomized controlled trials [RCTs] and eight observational studies) comprising 7,281 patients were analyzed. For overall mortality, no significant difference was found between the early norepinephrine group and late norepinephrine group in RCTs (OR, 0.70; 95% CI, 0.41-1.19) or observational studies (OR, 0.83; 95% CI, 0.54-1.29). In the two RCTs without a restrictive fluid strategy that prioritized vasopressors and lower IV fluid volumes, the early norepinephrine group showed significantly lower mortality than the late norepinephrine group (OR, 0.49; 95%, CI, 0.25-0.96). The early norepinephrine group demonstrated more mechanical ventilator-free days in observational studies (mean difference, 4.06; 95% CI, 2.82-5.30). The incidence of pulmonary edema was lower in the early norepinephrine group in the three RCTs that reported this outcome (OR, 0.43; 95% CI, 0.25-0.74). No differences were found in the other secondary outcomes.

INTERPRETATION

Overall mortality did not differ significantly between early and late norepinephrine administration for septic shock. However, early norepinephrine administration seemed to reduce pulmonary edema incidence, and mortality improvement was observed in studies without fluid restriction interventions, favoring early norepinephrine use.

Early management of adult sepsis and septic shock: Korean clinical practice guidelines

BACKGROUND

Despite recent advances and global improvements in sepsis recognition and supportive care, mortality rates remain high, and adherence to sepsis bundle components in Korea is low. To address this, the Korean Sepsis Alliance, affiliated with the Korean Society of Critical Care Medicine, developed the first sepsis treatment guidelines for Korea based on a comprehensive systematic review and meta-analysis.

METHODS

A de novo method was used to develop the guidelines. Methodologies included determining key questions, conducting a literature search and selection, assessing the risk of bias, synthesizing evidence, and developing recommendations. The certainty of evidence and the strength of recommendations were determined using the Grading of Recommendations, Assessment, Development, and Evaluations approach. Draft recommendations underwent internal and external review processes and public hearings. The development of these guidelines was supported by a research grant from the Korean Disease Control and Prevention Agency.

RESULTS

In these guidelines, we focused on early treatments for adult patients with sepsis and septic shock. Through the guideline development process, 12 key questions and their respective recommendations were formulated. These include lactate measurement, fluid therapies, target blood pressure, antibiotic administration, use of vasopressors and dobutamine, extracorporeal membrane oxygenation, and echocardiography.

CONCLUSIONS

These guidelines aim to support medical professionals in making appropriate decisions about treating adult sepsis and septic shock. We hope these guidelines will increase awareness of sepsis and reduce its mortality rate.

Identifying septic shock subgroups to tailor fluid strategies through multi-omics integration

Fluid management remains a critical challenge in the treatment of septic shock, with individualized approaches lacking. This study aims to develop a statistical model based on transcriptomics to identify subgroups of septic shock patients with varied responses to fluid strategy. The study encompasses 494 septic shock patients. A benefit score is derived from the transcriptome space, with higher values indicating greater benefits from restrictive fluid strategy. Adherence to the recommended strategy is associated with a hazard ratio of 0.82 (95% confidence interval: 0.64-0.92). When applied to the baseline hospital mortality rate of 16%, adherence to the recommended fluid strategy could potentially lower this rate to 13%. A proteomic signature comprising six proteins is developed to predict the benefit score, yielding an area under the curve of 0.802 (95% confidence interval: 0.752-0.846) in classifying patients who may benefit from a restrictive strategy. In this work, we develop a proteomic signature with potential utility in guiding fluid strategy for septic shock patients.

Association Between Arterial Pulse Waveform Analysis and Mortality in Patients With Septic Shock: A Retrospective Cohort Study Using Japanese Diagnosis Procedure Combination Data

Purpose: Specialized pressure transducers for arterial pulse waveform analysis (S-APWA) devices are dedicated kits connected to an arterial pressure catheter that monitors hemodynamic parameters, such as cardiac output, pulse pressure variation, and stroke volume variation, less invasively. While the association between the use of S-APWA devices and clinical outcomes in perioperative patients has been previously evaluated, its assessment in patients with septic shock remains inadequate. Materials and Methods: This retrospective cohort study utilized a nationwide Diagnosis Procedure Combination database in Japan. Adult patients with septic shock admitted to the intensive care unit (ICU) with arterial pressure catheter placement on the admission day from August 2012 to February 2021 were included. Hospitalizations meeting the eligibility criteria were categorized into groups based on S-APWA device usage. The primary outcome, evaluated using Cox regression analysis, was 30-day all-cause mortality in the propensity score overlap-weighted population. Secondary outcomes included in-hospital mortality, ICU duration, and overall hospital stay. Results: Among 5130 eligible hospitalizations, 643 were in the S-APWA group and 4487 were in the conventional pressure transducer group. Cox regression analysis within the propensity score overlap-weighted population showed no significant difference in 30-day mortality (adjusted hazard ratio: 0.94; 95% confidence interval: 0.9-1.38; P = .58). Logistic regression analysis indicated no significant differences in the in-hospital mortality. While the S-APWA group had prolonged ICU stays, no significant difference in the overall hospital stay was observed according to linear regression analyses. Conclusions: Our study found no significant association between S-APWA use and 30-day mortality in patients with septic shock. These findings offer insights into optimizing monitoring systems in ICUs.

Acute kidney injury in the acute care surgery patient: What you need to know

ABSTRACT

Acute kidney injury is associated with poor outcomes in the trauma and emergency general surgery population, and recent consensus definitions have allowed for significant advances in defining the burden of disease. The current definitions rely on overall functional measures (i.e., serum creatinine and urine output), which can be confounded by a variety of clinical factors. Biomarkers are increasingly being investigated as more direct diagnostic assays for the diagnosis of acute kidney injury and may allow earlier detection and more timely therapeutic intervention. Etiologies fall into two general categories: disorders of renal perfusion and exposure to nephrotoxic agents. Therapy is largely supportive, and prevention offers the best chance to decrease clinical impact.

Relationship Between Fluid Administration During the First Three Hours of Sepsis Resuscitation and Mortality: A Multicenter Observational Study

Background Timely and effective fluid resuscitation is vital for stabilizing sepsis while avoiding volume overload. We aimed to assess how the administration of a 30 mL/kg bolus fluid affects patients with sepsis within three hours of clinical outcomes. Methods This multicenter observational study included adult patients diagnosed with sepsis in 17 intensive care units at tertiary hospitals in Japan between July 2019 and August 2020. The clinical outcomes of patients with sepsis who received ≥30 mL/kg bolus fluid within three hours (30 × 3 group) were compared with those who received <30 mL/kg fluid (non-30 × 3 group). Results Of 172 eligible patients, 74 (43.0%) belonged to the 30 × 3 group, and 98 (57.0%) belonged to the non-30 × 3 group. The median Sequential Organ Failure Assessment score was 9 (interquartile range (Q1-Q3): 7-11) in the 30 × 3 group and 7 (Q1-Q3: 4-9) in the non-30 × 3 group (P < 0.01). The 28-day mortality rate was 29.7% in the 30 × 3 group and 12.2% in the non-30 × 3 group (P < 0.01). However, the adjusted odds ratio by the inverse probability of treatment weighting analysis with propensity score for the 28-day mortality rate of the 30 × 3 group compared with that in the non-30 × 3 group was 2.17 (95% confidence interval: 0.85-5.54). Among the propensity score-matched patients, the 28-day mortality rate was 30% in the 30 × 3 (n = 70) and non-30 × 3 (n = 95) groups, respectively (P = 0.72). Conclusions Patients with sepsis who received the 30 mL/kg bolus fluid within three hours experienced more severe clinical outcomes. However, it was not associated with the increased odds of the 28-day mortality.

Geo-economic Influence on the Effect of Fluid Volume for Sepsis Resuscitation: A Meta-Analysis

Rationale: Sepsis management relies on fluid resuscitation avoiding fluid overload and its related organ congestion. Objectives: To explore the influence of country income group on risk-benefit balance of fluid management strategies in sepsis. Methods: We searched e-databases for all randomized controlled trials on fluid resuscitation in patients with sepsis or septic shock up to January 2023, excluding studies on hypertonic fluids, colloids, and depletion-based interventions. The effect of fluid strategies (higher versus lower volumes) on mortality was analyzed per income group (i.e., low- and middle-income countries [LMICs] or high-income countries [HICs]). Measurements and Main Results: Twenty-nine studies (11,798 patients) were included in the meta-analysis. There was a numerically higher mortality in studies of LMICs as compared with those of HICs: median, 37% (interquartile range [IQR]: 26-41) versus 29% (IQR: 17-38; P = 0.06). Income group significantly interacted with the effect of fluid volume on mortality: Higher fluid volume was associated with higher mortality in LMICs but not in HICs: odds ratio (OR), 1.47; 95% confidence interval (95% CI): 1.14-1.90 versus 1.00 (95% CI: 0.87-1.16), P = 0.01 for subgroup differences. Higher fluid volume was associated with increased need for mechanical ventilation in LMICs (OR, 1.24 [95% CI: 1.08-1.43]) but not in HICs (OR, 1.02 [95% CI: 0.80-1.29]). Self-reported access to mechanical ventilation also significantly influenced the effect of fluid volume on mortality, which increased with higher volumes only in settings with limited access to mechanical ventilation (OR: 1.45 [95% CI: 1.09-1.93] vs. 1.09 [95% CI: 0.93-1.28], P = 0.02 for subgroup differences). Conclusions: In sepsis trials, the effect of fluid resuscitation approach differed by setting, with higher volume of fluid resuscitation associated with increased mortality in LMICs and in settings with restricted access to mechanical ventilation. The precise reason for these differences is unclear and may be attributable in part to resource constraints, participant variation between trials, or other unmeasured factors.

Assessment of the components of fluid balance in patients with septic shock: a prospective observational study

BACKGROUND

The optimal amount for initial fluid resuscitation is still controversial in sepsis and the contribution of non-resuscitation fluids in fluid balance is unclear. We aimed to investigate the main components of fluid intake and fluid balance in both survivors and non-survivor patients with septic shock within the first 72 hours.

METHODS

In this prospective observational study in two intensive care units, we recorded all fluids administered intravenously, orally, or enterally, and losses during specific time intervals from vasopressor initiation: T1 (up to 24 hours), T2 (24 to 48 hours) and T3 (48 to 72 hours). Logistic regression and a mathematical model assessed the association with mortality and the influence of severity of illness.

RESULTS

We included 139 patients. The main components of fluid intake varied across different time intervals, with resuscitation and non-resuscitation fluids such as antimicrobials and maintenance fluids being significant contributors in T1 and nutritional therapy in T2/T3. A positive fluid balance both in T1 and T2 was associated with mortality (p = 0.049; p = 0.003), while nutritional support in T2 was associated with lower mortality (p = 0.040). The association with mortality was not explained by severity of illness scores.

CONCLUSIONS

Non-resuscitation fluids are major contributors to a positive fluid balance within the first 48 hours of resuscitation. A positive fluid balance in the first 24 and 48 hours seems to independently increase the risk of death, while higher amount of nutrition seems protective. This data might inform fluid stewardship strategies aiming to improve outcomes and minimize complications in sepsis.

Association between intravenous fluid administration and endothelial glycocalyx shedding in humans: a systematic review

INTRODUCTION

Several studies have demonstrated associations between greater rate/volume of intravenous (IV) fluid administration and poorer clinical outcomes. One postulated mechanism for harm from exogenous fluids is shedding of the endothelial glycocalyx (EG).

METHODS

A systematic review using relevant search terms was performed using Medline, EMBASE and Cochrane databases from inception to October 2023. Included studies involved humans where the exposure was rate or volume of IV fluid administration and the outcome was EG shedding. The protocol was prospectively registered on PROSPERO: CRD42021275133.

RESULTS

The search yielded 450 articles, with 20 articles encompassing 1960 participants included in the review. Eight studies were randomized controlled clinical trials. Half of studies examined patients with sepsis and critical illness; the remainder examined perioperative patients or healthy subjects. Almost all reported blood measurements of soluble EG components; one study used in vivo video-microscopy to estimate EG thickness. Four of 10 sepsis studies, and 9 of 11 non-sepsis studies, found a positive relationship between IV fluid rate/volume and measures of EG shedding.

CONCLUSIONS

A trend toward an association between IV fluid rate/volume and EG shedding was found in studies of stable patients, but was not consistently observed among studies of septic and critically ill patients.

An Echocardiographic Approach for the Management of Shock: The Subcostal to Apical, Respiratory to Parasternal-Cardiac to Respiratory, Aortic to Stomach Protocol

Point of care ultrasound has become an integral part of critical care medicine, particularly for recognizing shock etiologies and guiding management. Most of the current ultrasonography guided shock protocols have been tailored towards a qualitative assessment of patients on presentation with shock. Unfortunately, the evolving nature of shock, particularly in the face of resuscitation and physiologic changes, demands a more sophisticated approach. This manuscript serves to present a comprehensive algorithm called the transthoracic Subcostal To Apical, Respiratory to paraSternal and transesophageal Cardiac to Respiratory, Aortic to StomacH ultrasonographic evaluations for the assessment of shock. This protocol is better suited for the critically ill patient in its ability to move beyond pattern recognition and focus on monitoring shock states from their presentation through their evolution. Not only is importance placed on the sequence of the exam, but also the identification of signs of chronic disease, the early incorporation of pulmonary evaluation, and the role for transesophageal imaging in critically ill patients with difficult surface imaging. Given the broad capabilities of bedside ultrasound, the Subcostal To Apical, Respiratory to paraSternal-Cardiac to Respiratory, Aortic to StomacH protocol serves as a multifaceted algorithm allowing for a nuanced and dynamic approach for the resuscitation of critically ill patients in shock.

Improving the precision of shock resuscitation by predicting fluid responsiveness with machine learning and arterial blood pressure waveform data

Fluid bolus therapy (FBT) is fundamental to the management of circulatory shock in critical care but balancing the benefits and toxicities of FBT has proven challenging in individual patients. Improved predictors of the hemodynamic response to a fluid bolus, commonly referred to as a fluid challenge, are needed to limit non-beneficial fluid administration and to enable automated clinical decision support and patient-specific precision critical care management. In this study we retrospectively analyzed data from 394 fluid boluses from 58 pigs subjected to either hemorrhagic or distributive shock. All animals had continuous blood pressure and cardiac output monitored throughout the study. Using this data, we developed a machine learning (ML) model to predict the hemodynamic response to a fluid challenge using only arterial blood pressure waveform data as the input. A Random Forest binary classifier referred to as the ML fluid responsiveness algorithm (MLFRA) was trained to detect fluid responsiveness (FR), defined as a ≥ 15% change in cardiac stroke volume after a fluid challenge. We then compared its performance to pulse pressure variation, a commonly used metric of FR. Model performance was assessed using the area under the receiver operating characteristic curve (AUROC), confusion matrix metrics, and calibration curves plotting predicted probabilities against observed outcomes. Across multiple train/test splits and feature selection methods designed to assess performance in the setting of small sample size conditions typical of large animal experiments, the MLFRA achieved an average AUROC, recall (sensitivity), specificity, and precision of 0.82, 0.86, 0.62. and 0.76, respectively. In the same datasets, pulse pressure variation had an AUROC, recall, specificity, and precision of 0.73, 0.91, 0.49, and 0.71, respectively. The MLFRA was generally well-calibrated across its range of predicted probabilities and appeared to perform equally well across physiologic conditions. These results suggest that ML, using only inputs from arterial blood pressure monitoring, may substantially improve the accuracy of predicting FR compared to the use of pulse pressure variation. If generalizable, these methods may enable more effective, automated precision management of critically ill patients with circulatory shock.

The association between increasing fluid balance, acute kidney injury and mortality in patients with sepsis and septic shock: A retrospective single center audit

PURPOSE

To determine whether a positive fluid balance is associated with AKI and mortality in sepsis and septic shock patients.

METHODS

A retrospective chart review of 482 patients treated for sepsis or septic shock. Patients were stratified according to quartiles of cumulative fluid balance on days 1 and 3. Logistic models were built to explore the association between fluid balance, AKI, and ICU mortality.

RESULTS

During the first days of ICU admission, fluid input did not differ between survivors and non-survivors, yet a significant difference in output resulted in a more positive fluid balance in non-survivors on day 1 (37.24 ± 31.98 ml/kg vs. 24.97 ± 23.76 ml/kg, p < 0.001) and day 3 (83.33 ± 70.86 ml/kg vs. 62.20 ± 45.90 ml/kg, P = 0.005). Using a logistic regression model, a positive fluid balance on day three was independently associated with higher ICU mortality (odds ratio 1.007 for every one ml/kg, P = 0038) and AKIN stage III (odds ratio 1.006 for every one ml/kg, p = 0.031).

CONCLUSION

In patients with sepsis and septic shock, a more positive fluid balance is associated with an increased incidence of acute kidney injury and death after correction for possible confounders.

Early sepsis in Australia and New Zealand: A point-prevalence study of haemodynamic resuscitation practices

OBJECTIVE

Optimal resuscitation of sepsis-induced hypotension is uncertain, particularly the role of restrictive fluid strategies, leading to variability in usual practice. The objective of this study is to understand resuscitation practices in patients presenting to ED with early sepsis.

METHODS

Design, participants and setting: Prospective, observational, multicentre, single-day, point-prevalence study enrolling adult patients present in 51 Australian and New Zealand ICUs at 10.00 hours, 8 June 2021.

MAIN OUTCOME MEASURES

Site-level data on sepsis policies and patient-level demographic data, presence of sepsis and fluid and vasopressor administration in the first 24 h post-ED presentation.

RESULTS

A total of 722 patients were enrolled. ED was the ICU admission source for 222 of 722 patients (31.2%) and 78 of 222 patients (35%) met the criteria for sepsis within 24 h of ED presentation. Median age of the sepsis cohort was 61 (48-72) years, 58% were male and respiratory infection was the commonest cause (53.8%). The sepsis cohort had a higher severity of illness than the non-sepsis cohort (144/222 patients) and chronic immunocompromise was more common. Of 78 sepsis patients, 55 (71%) received ≥1 fluid boluses with 500 and 1000 mL boluses equally common (both 49%). In the first 24 h, 2335 (1409-3125) mL (25.3 [13.2-42.9] mL/kg) was administered. Vasopressors were administered in 53 of 78 patients (68%) and for 25 patients (47%) administration was peripheral.

CONCLUSIONS

ICU patients presenting to the ED with sepsis receive less fluids than current international recommendations and peripheral vasopressor administration is common. This finding supports the conduct of clinical trials evaluating optimal fluid dose and vasopressor timing for early sepsis-induced hypotension.

RESTRICTIVE FLUID RESUSCITATION IN SEPTIC SHOCK PATIENTS HAS LOWER MORTALITY AND ORGAN DYSFUNCTION RATES THAN STANDARD THERAPY

ABSTRACT

Background : The influence of restrictive fluid resuscitation and the early administration of vasopressors on the clinical outcomes in patients with septic shock are not fully understood. The purpose of this study was to evaluate the effects of restrictive fluid management on mortality and organ dysfunction in patients with septic shock. Methods : This study included consecutive patients with septic shock in need of fluid resuscitation. Based on the fluid management provided in the initial resuscitation phase, a comparison was made between a restrictive group and a standard fluid management group. The primary outcome was in-hospital death, whereas secondary outcomes included organ dysfunction and other adverse events. Results : A total of 238 patients were included in this study. Restrictive fluid management was administered to 59.2% of patients, whereas 40.8% received standard fluid management. Restrictive resuscitation was associated with a lower in-hospital mortality rate (24.8% vs. 52.6%), as well as a shorter median intensive care unit stay (8.0 vs. 11.0 days). The restrictive strategy was associated with a significantly lower prevalence of new-onset acute kidney injury (25.5% vs. 51.5%) and a decrease in the incidence of renal replacement therapy (20.6% vs. 40.2%). The standard group had a higher risk of the need for mechanical ventilation and a significantly lower median number of days without a ventilator than the restrictive group. The median duration of vasopressor-free days in the restrictive group was significantly longer than that in the standard group (25.0 vs. 18.0). The administration rate of inotropes in the restrictive group was significantly lower than that in the standard group. A multivariate logistic regression model showed that restrictive fluid management (odds ratio [OR], 0.312; 95% confidence interval [CI], 0.098-0.994) and vasopressor-free days (OR, 0.807; 95% CI, 0.765-0.851) protect against in-hospital death, whereas Acute Physiology and Chronic Health Evaluation II scores (OR, 1.121; 95% CI, 1.018-1.234) were independent risk factors for in-hospital death. Conclusions : Restrictive fluid resuscitation and early vasopressor protocol in patients with septic shock are associated with better outcomes, indicating that this regimen is feasible and safe.

Dose-related effects of norepinephrine on early-stage endotoxemic shock in a swine model

Background

The benefits of early use of norepinephrine in endotoxemic shock remain unknown. We aimed to elucidate the effects of different doses of norepinephrine in early-stage endotoxemic shock using a clinically relevant large animal model.

Methods

Vasodilatory shock was induced by endotoxin bolus in 30 Bama suckling pigs. Treatment included fluid resuscitation and administration of different doses of norepinephrine, to induce return to baseline mean arterial pressure (MAP). Fluid management, hemodynamic, microcirculation, inflammation, and organ function variables were monitored. All animals were supported for 6 h after endotoxemic shock.

Results

Infused fluid volume decreased with increasing norepinephrine dose. Return to baseline MAP was achieved more frequently with doses of 0.8 µg/kg/min and 1.6 µg/kg/min (P <0.01). At the end of the shock resuscitation period, cardiac index was higher in pigs treated with 0.8 µg/kg/min norepinephrine (P <0.01), while systemic vascular resistance was higher in those receiving 0.4 µg/kg/min (P <0.01). Extravascular lung water level and degree of organ edema were higher in animals administered no or 0.2 µg/kg/min norepinephrine (P <0.01), while the percentage of perfused small vessel density (PSVD) was higher in those receiving 0.8 µg/kg/min (P <0.05) and serum lactate was higher in the groups administered no and 1.6 µg/kg/min norepinephrine (P <0.01).

Conclusions

The impact of norepinephrine on the macro- and micro-circulation in early-stage endotoxemic shock is dose-dependent, with very low and very high doses resulting in detrimental effects. Only an appropriate norepinephrine dose was associated with improved tissue perfusion and organ function.

The intensity of organ support: Restrictive or aggressive therapy for critically ill patients

The intensity of organ support has received attention in recent years. To make better clinical decisions, we should understand the mechanisms and benefits, and disadvantages of the different intensities of organ support in critically ill patients. Therapeutic strategies such as supplemental oxygen therapy, mechanical ventilation, respiratory stimulant, vasoactive agents, transfusion, albumin infusion, fluid management, renal placement, and nutrition support, if they are implemented in accordance with an aggressive strategy, could result in side effects and/or complications, resulting in iatrogenic harm in critically ill patients. It is found that the intensity of organ support is not a determining factor in prognosis. A normal rather than supernormal physiological target is recommended for support therapy.

Restrictive Versus Liberal Fluid Regimen in Refractory Sepsis and Septic Shock: A Systematic Review and Meta-Analysis

The optimal fluid management strategy for patients with sepsis remains a topic of debate. This meta-analysis aims to evaluate the impact of restrictive versus liberal fluid regimens on mortality, adverse events, and other clinical outcomes in patients with sepsis. We systematically reviewed 11 randomized controlled trials published between 2008 and 2023, comprising a total of 4,121 participants. The studies assessed 90-day mortality, 30-day mortality, adverse events, hospital length of stay, ICU admission rate, mechanical ventilation, ventilator-free days, ICU-free days, and vasopressor-free days. Quality assessments indicated minimal bias across the studies. The meta-analysis showed no statistically significant difference in 90-day mortality between restrictive and liberal fluid regimens (OR, 0.93; 95% CI, 0.80 to 1.70; P=0.30). Similar results were observed for 30-day mortality (OR, 0.73; 95% CI, 0.30 to 1.80; P=0.50). Adverse events were comparable between the two groups (OR, 0.81; 95% CI, 0.55 to 1.19; P=0.28). Furthermore, there were no significant differences in hospital length of stay (OR, 0.47; 95% CI, -0.85 to 1.80; P=0.48) or ICU admission rate (OR, 1.09; 95% CI, 0.66 to 1.77; P=0.75) between the restrictive and liberal fluid regimens. Regarding mechanical ventilation and ventilator-free days, no significant distinctions were observed (OR, 0.87; 95% CI, 0.65 to 1.17; P=0.48; OR, 0.99; 95% CI, -0.17 to 2.15; P=0.09, respectively). ICU-free days and vasopressor-free days also showed no significant differences between the two groups (OR, 0.97; 95% CI, -0.28 to 2.21; P=0.13; OR, -0.38; 95% CI, -1.14 to 0.37; P=0.32, respectively). This comprehensive meta-analysis of clinical trials suggests that restrictive and liberal fluid management strategies have comparable outcomes in patients with sepsis, including mortality, adverse events, and various clinical parameters. However, most studies favored restrictive fluid regimen over liberal approach regarding the number of vasopressor-free days, need for mechanical ventilation, adverse events, 30-day mortality, and 90-day mortality in sepsis patients.

Lower vs Higher Fluid Volumes in Adult Patients With Sepsis: An Updated Systematic Review With Meta-Analysis and Trial Sequential Analysis

BACKGROUND

IV fluids are recommended for adults with sepsis. However, the optimal strategy for IV fluid management in sepsis is unknown, and clinical equipoise exists.

RESEARCH QUESTION

Do lower vs higher fluid volumes improve patient-important outcomes in adult patients with sepsis?

STUDY DESIGN AND METHODS

We updated a systematic review with meta-analysis and trial sequential analysis of randomized clinical trials assessing lower vs higher IV fluid volumes in adult patients with sepsis. The coprimary outcomes were all-cause mortality, serious adverse events, and health-related quality of life. We followed the recommendations from the Cochrane Handbook and used the Grading of Recommendations Assessment, Development and Evaluation approach. Primary conclusions were based on trials with low risk of bias if available.

RESULTS

We included 13 trials (N = 4,006) with four trials (n = 3,385) added to this update. The meta-analysis of all-cause mortality in eight trials with low risk of bias showed a relative risk of 0.99 (97% CI, 0.89-1.10; moderate certainty evidence). Six trials with predefined definitions of serious adverse events showed a relative risk of 0.95 (97% CI, 0.83-1.07; low certainty evidence). Health-related quality of life was not reported.

INTERPRETATION

Among adult patients with sepsis, lower IV fluid volumes probably result in little to no difference in all-cause mortality compared with higher IV fluid volumes, but the interpretation is limited by imprecision in the estimate, which does not exclude potential benefit or harm. Similarly, the evidence suggests lower IV fluid volumes result in little to no difference in serious adverse events. No trials reported on health-related quality of life.

TRIAL REGISTRATION

PROSPERO; No.: CRD42022312572; URL: https://www.crd.york.ac.uk/prospero/.

The Effects of Restrictive Fluid Resuscitation on the Clinical Outcomes in Patients with Sepsis or Septic Shock: A Meta-Analysis of Randomized-Controlled Trials

This study aims to assess the impact of a restrictive resuscitation strategy on the outcomes of patients with sepsis and septic shock. This meta-analysis was conducted in accordance with the recommendations from the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) guidelines. A systematic search was performed in databases, including PubMed, Web of Science, EMBASE, and the Cochrane Library, covering the period from the inception of the database to August 2023, with no limitations on the language of publication. Outcomes assessed in the meta-analysis included mortality, duration of intensive care unit (ICU) stay in days, duration of mechanical ventilation in days, acute kidney injury (AKI) or the need for renal replacement therapy (RRT), and length of hospital stay in days. Overall, 12 studies met the inclusion criteria and were included in the present meta-analysis. The findings of this study indicate that although the risk of mortality was lower in fluid restriction compared to the control group, the difference was statistically insignificant (risk ratio (RR): 0.98; 95% confidence interval (CI): 0.9-1.05; P value: 0.61). Additionally, the duration of mechanical ventilation was significantly shorter in the restrictive fluid group compared to its counterparts (mean difference (MD): -1.02; 95% CI: -1.65 to -0.38; P value: 0.003). There were no significant differences found in relation to the duration of ICU stays, the incidence of AKI, the requirement for RRT, or the length of hospital stays measured in days.

Practice and effect evaluation of early restrictive fluid resuscitation strategy in the nursing care of patients with sepsis in the emergency department: a retrospective cohort study

OBJECTIVE

To explore the practice and effect evaluation of the early restrictive fluid resuscitation strategy in the nursing care of patients with sepsis in the emergency department.

METHODS

A total of 239 sepsis patients, who were treated in the emergency department of our hospital from January to September 2020, were selected as the participants of this study, and a retrospective analysis was performed. According to different methods of fluid resuscitation, they were divided into an improved group and a control group. One hundred and twelve patients who received restrictive fluid resuscitation were in the improved group; another 127 patients who received adequate fluid resuscitation were in the control group. The ICU stay time, ventilator use time, and 28-day mortality rate of the two groups were observed. The hemodynamic indices, acute physiology and chronic health evaluation (APACHE) II score, sequential organ failure assessment (SOFA) score, and complications of the two groups before and after treatment were compared.

RESULTS

After treatment, in the improved group, the APACHE II and SOFA scores were lower than in the control group, fluid replacement decreased, lactate clearance increased, ICU admission time shortened and the proportion of ventilator time to ICU admission time decreased. The incidence of acute respiratory distress syndrome (ARDS), cTn I and brain natriuretic peptic in the improved group were significantly lower than those in the control group. From the dimension within the group, the APACHE II score, SOFA score, heart rate and shock index were lower after treatment than before treatment in both the improved and control groups.

CONCLUSION

Restricted fluid resuscitation can effectively alleviate the condition of emergency sepsis patients, improve hemodynamics, reduce the incidence of ARDS, and prevent patient deaths. It is worthy of clinical application.

The Effect of Fluid Pre-loading on Vital Signs and Hemodynamic Parameters in a Porcine Model of Lipopolysaccharide-Induced Endotoxemia

Background Animal models of distributive hypotension and resuscitation allow the assessment of hemodynamic monitoring modalities and resuscitation strategies. The fluid-first paradigm for resuscitation is currently being challenged with clinical trials. In this investigation, venous return and perfusion are assessed, and full hemodynamics are characterized, in a porcine model of endotoxemic hypotension with and without fluid pre-loading. Methods Two groups of six pigs had the induction of standardized endotoxemic hypotension ("critical hypotension"). Group 1 underwent four 10 cc/kg crystalloid boluses, and Group 2 was not fluid pre-resuscitated. Both groups underwent progressive norepinephrine (NE) up-titration to 0.25 mcg/kg/minute over 30 minutes. Vital signs, central parameters, and laboratory values were obtained at baseline, "critical hypotension," after each bolus and during NE administration. Results Endotoxemia decreased the systemic vascular resistance (SVR) in Group 1 (1031±106 dyn/s/cm-5 versus 738±258 dyn/s/cm-5; P=0.03) and Group 2 (1121±196 dyn/s/cm-5 versus 759±342 dyn/s/cm-5; P=0.003). In Group 1, the four fluid boluses decreased heart rate (HR), pulmonary capillary wedge pressure (PCWP), and central venous pressure (CVP) (P<0.05). No changes were observed in blood pressure, cardiac output (CO), or lactate. NE up-titration increased HR in Group 1 and decreased CVP in both groups. Higher final CVP (11 {3} versus 4 {4} mmHg; P=0.01) and PCWP (5 {1} versus 2 {2} mmHg; P=0.005) values were observed in Group 1 relative to Group 2, reflecting increased venous return. Conclusions Porcine endotoxemic hypotension and resuscitation were robustly characterized. In this model, fluid loading improved venous return with NE, though perfusion (CO) was preserved by increased NE-induced chronotropy.

Fluids and Early Vasopressors in the Management of Septic Shock: Do We Have the Right Answers Yet?

Septic shock is a common condition associated with hypotension and organ dysfunction. It is associated with high mortality rates of up to 60% despite the best recommended resuscitation strategies in international guidelines. Patients with septic shock generally have a Mean Arterial Pressure below 65 mmHg and hypotension is the most important determinant of mortality among this group of patients. The extent and duration of hypotension are important. The two initial options that we have are 1) administration of intravenous (IV) fluids and 2) vasopressors, The current recommendation of the Surviving Sepsis Campaign guidelines to administer 30 ml/kg fluid cannot be applied to all patients. Complications of fluid over-resuscitation further delay organ recovery, prolong ICU and hospital length of stay, and increase mortality. The only reason for administering intravenous fluids in a patient with circulatory shock is to increase the mean systemic filling pressure in a patient who is volume-responsive, such that cardiac output also increases. The use of vasopressors seems to be a more appropriate strategy, the very early administration of vasopressors, preferably during the first hour after diagnosis of septic shock, may have a multimodal action and potential advantages, leading to lower morbidity and mortality in the management of septic patients. Vasopressor therapy should be initiated as soon as possible in patients with septic shock.

Evolving Management Practices for Early Sepsis-induced Hypoperfusion: A Narrative Review

Sepsis causes significant morbidity and mortality worldwide. Resuscitation is a cornerstone of management. This review covers five areas of evolving practice in the management of early sepsis-induced hypoperfusion: fluid resuscitation volume, timing of vasopressor initiation, resuscitation targets, route of vasopressor administration, and use of invasive blood pressure monitoring. For each topic, we review the seminal evidence, discuss the evolution of practice over time, and highlight questions for additional research. Intravenous fluids are a core component of early sepsis resuscitation. However, with growing concerns about the harms of fluid, practice is evolving toward smaller-volume resuscitation, which is often paired with earlier vasopressor initiation. Large trials of fluid-restrictive, vasopressor-early strategies are providing more information about the safety and potential benefit of these approaches. Lowering blood pressure targets is a means to prevent fluid overload and reduce exposure to vasopressors; mean arterial pressure targets of 60-65 mm Hg appear to be safe, at least in older patients. With the trend toward earlier vasopressor initiation, the need for central administration of vasopressors has been questioned, and peripheral vasopressor use is increasing, although it is not universally accepted. Similarly, although guidelines suggest the use of invasive blood pressure monitoring with arterial catheters in patients receiving vasopressors, blood pressure cuffs are less invasive and often sufficient. Overall, the management of early sepsis-induced hypoperfusion is evolving toward fluid-sparing and less-invasive strategies. However, many questions remain, and additional data are needed to further optimize our approach to resuscitation.

Effect of intravenous fluid volume on biomarkers of endothelial glycocalyx shedding and inflammation during initial resuscitation of sepsis

PURPOSE

To investigate the effect of IV fluid resuscitation on endothelial glycocalyx (EG) shedding and activation of the vascular endothelium and inflammation.

MATERIALS AND METHODS

A planned biomarker sub-study of the REFRESH trial in which emergency department (ED) patients) with suspected sepsis and hypotension were randomised to a restricted fluid/early vasopressor regimen or IV fluid resuscitation with later vasopressors if required (usual care). Blood samples were collected at randomisation (T0) and at 3 h (T3), 6 h (T6)- and 24 h (T24) for measurement of a range of biomarkers if EG shedding, endothelial cell activation and inflammation.

RESULTS

Blood samples were obtained in 95 of 99 enrolled patients (46 usual care, 49 restricted fluid). Differences in the change in biomarker over time between the groups were observed for Hyaluronan (2.2-fold from T3 to T24, p = 0.03), SYN-4 (1.5-fold from T3 to T24, P = 0.01) and IL-6 (2.5-fold from T0 to T3, p = 0.03). No difference over time was observed between groups for the other biomarkers.

CONCLUSIONS

A consistent signal across a range of biomarkers of EG shedding or of endothelial activation or inflammation was not demonstrated. This could be explained by pre-existing EG shedding or overlap between the fluid volumes administered in the two groups in this clinical trial. Trial registration Australia New Zealand Clinical Trials Registry ACTRN126160000006448 Registered 12 January 2016.

How I personalize fluid therapy in septic shock?

During septic shock, fluid therapy is aimed at increasing cardiac output and improving tissue oxygenation, but it poses two problems: it has inconsistent and transient efficacy, and it has many well-documented deleterious effects. We suggest that there is a place for its personalization according to the patient characteristics and the clinical situation, at all stages of circulatory failure. Regarding the choice of fluid for volume expansion, isotonic saline induces hyperchloremic acidosis, but only for very large volumes administered. We suggest that balanced solutions should be reserved for patients who have already received large volumes and in whom the chloremia is rising. The initial volume expansion, intended to compensate for the constant hypovolaemia in the initial phase of septic shock, cannot be adapted to the patient's weight only, as suggested by the Surviving Sepsis Campaign, but should also consider potential absolute hypovolemia induced by fluid losses. After the initial fluid infusion, preload responsiveness may rapidly disappear, and it should be assessed. The choice between tests used for this purpose depends on the presence or absence of mechanical ventilation, the monitoring in place and the risk of fluid accumulation. In non-intubated patients, the passive leg raising test and the mini-fluid challenge are suitable. In patients without cardiac output monitoring, tests like the tidal volume challenge, the passive leg raising test and the mini-fluid challenge can be used as they can be performed by measuring changes in pulse pressure variation, assessed through an arterial line. The mini-fluid challenge should not be repeated in patients who already received large volumes of fluids. The variables to assess fluid accumulation depend on the clinical condition. In acute respiratory distress syndrome, pulmonary arterial occlusion pressure, extravascular lung water and pulmonary vascular permeability index assess the risk of worsening alveolar oedema better than arterial oxygenation. In case of abdominal problems, the intra-abdominal pressure should be taken into account. Finally, fluid depletion in the de-escalation phase is considered in patients with significant fluid accumulation. Fluid removal can be guided by preload responsiveness testing, since haemodynamic deterioration is likely to occur in patients with a preload dependent state.

Active fluid de-resuscitation in critically ill patients with septic shock: A systematic review and meta-analysis

PURPOSE

To evaluate the impact of active fluid de-resuscitation on mortality in critically ill patients with septic shock.

METHODS

A systematic search was performed on PubMed, EmBase, and the Cochrane Library databases. Trials investigating active fluid de-resuscitation and reporting data on mortality in patients with septic shock were eligible. The primary objective was the impact of active de-resuscitation in patients with septic shock on short-term mortality. Secondary outcomes were whether de-resuscitation lead to a fluid separation, and the impact of de-resuscitation on patient-centred outcomes.

RESULTS

Thirteen trials (8,030 patients) were included in the systematic review, whereof 5 randomised-controlled trials (RCTs) were included in the meta-analysis. None of the RCTs showed a reduction in mortality with active de-resuscitation measures (relative risk (RR) 1.12 [95%-CI 0.84 - 1.48]). Fluid separation was achieved by two RCTs. Evidence from non-randomised trials suggests a mortality benefit with de-resuscitation strategies and indicates a trend towards a more negative fluid balance. Patient-centred outcomes were not influenced in the RCTs, and only one non-randomised trial revealed an impact on the duration of mechanical ventilation and renal replacement requirement (RRT).

CONCLUSION

We found no evidence for superiority of active fluid de-resuscitation compared to usual care regarding mortality, fluid balance or patient-centred outcomes in patients with septic shock. Current evidence is limited by the lack of high-quality RCTs in patients with septic shock, the small sample sizes and the heterogeneity of the applied de-resuscitation techniques. In addition, validity of the majority of RCTs is compromised by their inability to achieve fluid separation.

Restrictive resuscitation in patients with sepsis and mortality: A systematic review and meta-analysis with trial sequential analysis

STUDY OBJECTIVE

Although fluid resuscitation is recommended by the Society of Critical Care Medicine Surviving Sepsis Campaign Guidelines, risks of volume overload persist.The objective of this systematic review is to assess the effects of a restrictive fluid resuscitation approach in the septic patient both during and after the initial resuscitation period (30  ml/kg).

DESIGN

A systematic review and meta-analysis with trial sequential analysis (TSA) of randomized controlled trials was conducted. Two blinded reviewers independently assessed and included studies that evaluated adult patients with sepsis involving a comparator group with an effective restrictive fluid resuscitation approach. The primary outcome was mortality. Secondary outcomes included rates of acute kidney injury (AKI), renal replacement therapy (RRT), ventilator days, intensive care unit (ICU) and hospital length of stay (LOS), duration of vasopressor therapy, and limb (or digital) ischemia.

SETTING

PubMed and Medline databases were queried for the search.

PATIENTS

A total of eight trials in 2375 patients were included.

INTERVENTION

Effective restrictive fluid resuscitation compared with standard of care.

MEASUREMENTS AND MAIN RESULTS

The risk of bias was high in six studies and low in two studies, and all studies implemented fluid restriction after a 30-ml/kg infusion of fluids. Fluid restriction did not significantly reduce mortality in all studies compared to usual care (37% vs. 40% with usual care; risk ratio [RR] 0.90, 95% confidence interval [CI] 0.76-1.06, p = 0.23, I2  = 24%) or by TSA findings. There were no significant differences in rates of AKI or RRT (5 studies), LOS in ICU (4 studies) or hospital (3 studies), duration of vasopressor therapy (6 studies), or incidence of limb or digital ischemia (3 studies). However, fluid restriction significantly reduced ventilator days as evaluated in seven studies (mean difference - 1.25 days, 95% CI -1.92 to -0.58  days, p = 0.0003, I2  = 90%).

CONCLUSION

This study demonstrated that a restrictive resuscitation strategy in sepsis resulted in no difference in mortality but may reduce ventilator days. Larger randomized trials are required to determine the optimal management of fluids in patients with sepsis.

Renal medicine in the intensive care unit: a narrative review

Kidney disease, both acute and chronic, is commonly encountered on the intensive care unit. Due to the role the kidneys play in whole body homeostasis, it follows that their dysfunction has wide-ranging implications and can affect prescribing and therapeutic management. This narrative review discusses the pathophysiology of acute kidney injury and chronic kidney disease, and how this relates to critically unwell patients. We cover several aspects of the management of renal dysfunction on the critical care unit, exploring some of the recurrent themes within the literature, including type and timing of kidney replacement therapy, management of acute kidney injury, as well as discussing how novel biomarkers for acute kidney injury may help to identify patients suffering from acute kidney injury as well as risk stratifying these patients. We discuss how early involvement of specialist nephrology services can improve outcomes in patients with kidney disease as well as offer valuable diagnostic and specialist management advice, particularly for patients with established end stage kidney disease and patients who are already known to nephrology services. We also explore some of the ongoing research questions that need to be answered within this arena.

Fluid management of emergency department patients with sepsis-A survey of fluid resuscitation practices

BACKGROUND

Fluid administration and resuscitation of patients with sepsis admitted through emergency departments (ED) remains a challenge, and evidence is sparse especially in sepsis patients without shock. We aimed to investigate emergency medicine physicians' and nurses' perceptions, self-reported decision-making and daily behavior, and challenges in fluid administration of ED sepsis patients.

METHODS

We developed and conducted a multicenter, web-based, cross-sectional survey focusing on fluid administration to ED patients with sepsis sent to all nurses and physicians from the five EDs in the Central Denmark Region. The survey consisted of three sections: (1) baseline information; (2) perceptions of fluid administration and daily practice; and (3) clinical scenarios about fluid administration. The survey was performed from February to June, 2021.

RESULTS

In total, 138 of 246 physicians (56%) and 382 of 595 nurses (64%) responded to the survey. Of total, 94% of physicians and 97% of nurses regarded fluid as an important part of sepsis treatment. Of total, 80% of physicians and 61% of nurses faced challenges regarding fluid administration in the ED, and decisions were usually based on clinical judgment. The most common challenge was the lack of guidelines for fluid administration. Of total, 96% agreed that they would like to learn more about fluid administration, and 53% requested research in fluid administration of patients with sepsis. For a normotensive patient with sepsis, 46% of physicians and 44% of nurses administered 1000 ml fluid in the first hour. Of total, 95% of physicians and 89% of nurses preferred to administer ≥1000 ml within an hour if the patients' blood pressure was 95/60 at admission. There was marked variability in responses. Blood pressure was the most commonly used trigger for fluid administration. Respondents preferred to administer less fluid if the patient in the scenario had known renal impairment or heart failure. Normal saline was the preferred fluid.

CONCLUSION

Fluid administration is regarded as an important but challenging aspect of sepsis management. Responses to scenarios revealed variability in fluid volumes. Blood pressure was the most used trigger. ED nurses and physicians request evidence-based guidelines to improve fluid administration.

A burden of fluid, sodium, and chloride due to intravenous fluid therapy in patients with respiratory support: a post-hoc analysis of a multicenter cohort study

Background

Fluid creep, including fluids administered as drug diluents and for the maintenance of catheter patency, is the major source of fluid intake in critically ill patients. Although hypoxemia may lead to fluid restriction, the epidemiology of fluid creep in patients with hypoxemia is unclear. This study aimed to address the burden due to fluid creep among patients with respiratory support according to oxygenation status.

Methods

We conducted a post-hoc analysis of a prospective multicenter cohort study conducted in 23 intensive care units (ICUs) in Japan from January to March 2018. Consecutive adult patients who underwent invasive or noninvasive ventilation upon ICU admission and stayed in the ICU for more than 24 h were included. We excluded the following patients when no fluids were administered within 24 h of ICU admission and no records of the ratio of arterial oxygen partial pressure to fractional inspired oxygen. We investigated fluid therapy until 7 days after ICU admission according to oxygenation status. Fluid creep was defined as the fluids administered as drug diluents and for the maintenance of catheter patency when administered at ≤ 20 mL/h.

Results

Among the 588 included patients, the median fluid creep within 24 h of ICU admission was 661 mL (25.2% of the total intravenous-fluid volume), and the proportion of fluid creep gradually increased throughout the ICU stay. Fluid creep tended to decrease throughout ICU days in patients without hypoxemia and in those with mild hypoxemia (p < 0.001 in both patients), but no significant trend was observed in those with severe hypoxemia (p = 0.159). Similar trends have been observed in the proportions of sodium and chloride caused by fluid creep.

Conclusions

Fluid creep was the major source of fluid intake among patients with respiratory support, and the burden due to fluid creep was prolonged in those with severe hypoxemia. However, these findings may not be conclusive as this was an observational study. Interventional studies are, therefore, warranted to assess the feasibility of fluid creep restriction.

Trial registration UMIN-CTR, the Japanese clinical trial registry (registration number: UMIN 000028019, July 1, 2017).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01073-x.

Fluid resuscitation of at least 30 mL/kg was not associated with decreased mortality in patients with infection, signs of hypoperfusion, and a do-not-intubate order

Aim

Administration of at least 30 mL/kg of fluid as fluid resuscitation is recommended for patients with sepsis and signs of hypoperfusion. However, it is not clear whether this is appropriate for patients with a do‐not‐intubate (DNI) order. This study evaluated the association between volume of fluid resuscitation and outcomes in patients with infection, signs of hypoperfusion, and a DNI order in an emergency department.

Methods

This was a single‐center retrospective cohort study. We classified the infected patients with signs of hypoperfusion and a DNI order seen in our emergency department between April 1, 2015 and November 31, 2020 into the standard fluid resuscitation group (≥30 mL/kg) and the restricted fluid resuscitation group (<30 mL/kg). We compared with in‐hospital mortality and the rate of discharge to home in two groups.

Results

Of 367 patients, 149 received standard fluid resuscitation and 218 received restricted fluid resuscitation. In‐hospital mortality was similar in each group (40/149 and 62/218, respectively). Standard fluid resuscitation was not associated with in‐hospital mortality (adjusted odds ratio [aOR], 1.05; 95% confidence interval [CI], 0.62–1.77, P = 0.86), but was associated with a significantly lower rate of discharge to home (aOR, 0.55; 95% CI, 0.30–0.98, P = 0.043). There was no significant difference in respiratory rate or need for oxygen therapy post‐resuscitation between the two groups.

Conclusion

This study suggests that fluid resuscitation may be not beneficial for infected patients with signs of hypoperfusion and a DNI order. Further studies should be conducted on the options for resuscitation management for these patients.

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.

Pathophysiology, mechanisms, and managements of tissue hypoxia

Oxygen is needed to generate aerobic adenosine triphosphate and energy that is required to support vital cellular functions. Oxygen delivery (DO2) to the tissues is determined by convective and diffusive processes. The ability of the body to adjust oxygen extraction (ERO2) in response to changes in DO2 is crucial to maintain constant tissue oxygen consumption (VO2). The capability to increase ERO2 is the result of the regulation of the circulation and the effects of the simultaneous activation of both central and local factors. The endothelium plays a crucial role in matching tissue oxygen supply to demand in situations of acute drop in tissue oxygenation. Tissue oxygenation is adequate when tissue oxygen demand is met. When DO2 is severely compromised, a critical DO2 value is reached below which VO2 falls and becomes dependent on DO2, resulting in tissue hypoxia. The different mechanisms of tissue hypoxia are circulatory, anaemic, and hypoxic, characterised by a diminished DO2 but preserved capacity of increasing ERO2. Cytopathic hypoxia is another mechanism of tissue hypoxia that is due to impairment in mitochondrial respiration that can be observed in septic conditions with normal overall DO2. Sepsis induces microcirculatory alterations with decreased functional capillary density, increased number of stopped-flow capillaries, and marked heterogeneity between the areas with large intercapillary distance, resulting in impairment of the tissue to extract oxygen and to satisfy the increased tissue oxygen demand, leading to the development of tissue hypoxia. Different therapeutic approaches exist to increase DO2 and improve microcirculation, such as fluid therapy, transfusion, vasopressors, inotropes, and vasodilators. However, the effects of these agents on microcirculation are quite variable.

No association between intravenous fluid volume and endothelial glycocalyx shedding in patients undergoing resuscitation for sepsis in the emergency department

Endothelial glycocalyx (EG) shedding is associated with septic shock and described following intravenous (IV) fluid administration. To investigate the possible impact of IV fluids on the pathobiology of septic shock we investigated associations between biomarkers of EG shedding and endothelial cell activation, and relationships with IV fluid volume. Serum samples were obtained on admission (T0) and at 24 h (T24) in patients undergoing haemodynamic resuscitation for suspected septic shock in the emergency department. Biomarkers of EG shedding—Syndecan-1 (Syn-1), Syndecan-4 (Syn-4), Hyaluronan, endothelial activation—Endothelin-1 (ET-1), Angiopoeitin-2 (Ang-2), Vascular Endothelial Growth Factor Receptor-1(VEGF-1) and leucocyte activation/inflammation—Resistin, Neutrophil Gelatinase Associated Lipocalin (NGAL) and a marker of cardiac stretch—Pro-Atrial Natriuretic Peptide (Pro-ANP) were compared to the total IV fluid volume administered using Tobit regression. Data on 86 patients (52 male) with a mean age of 60 (SD 18) years were included. The mean fluid volume administered to T24 was 4038 ml (SD 2507 ml). No significant association between fluid volume and Pro-ANP or any of the biomarkers were observed. Syn-1 and Syn-4 were significantly correlated with each other (Spearman Rho 0.43, p < 0.001) but not with Hyaluronan. Syn-1 and Syn-4 both correlated with VEGFR-1 (Rho 0.56 and 0.57 respectively, p < 0.001) whereas Hyaluronan correlated with ET-1 (Rho 0.43, p < 0.001) and Ang-2 (Rho 0.43, p < 0.001). There was no correlation between Pro-ANP and any of the EG biomarkers. Distinct patterns of association between biomarkers of EG shedding and endothelial cell activation were observed among patients undergoing resuscitation for sepsis. No relationship between IV fluid volume and Pro-ANP or any of the other biomarkers was observed.

[Pathophysiology of septic shock]

Sepsis and septic shock result from an inadequate host response to an infection, which causes organ dysfunction. The progression of this condition is manifested by the occurrence of successive clinical stages, resulting from the systemic inflammatory response secondary to the activation of different inflammatory mediators, leading to organ dysfunction. There is a high burden of evidence on the role of endotoxin in the pathogenesis of sepsis and its crucial role in triggering the inflammatory response in sepsis caused by gram-negative bacteria. The coagulation cascade activation in sepsis patients is part of the host's adaptive immune response to infection. The endothelium is the main target in sepsis, which is metabolically active and can.

Restrictive Fluid Administration vs. Standard of Care in Emergency Department Sepsis Patients (REFACED Sepsis)-protocol for a multicenter, randomized, clinical, proof-of-concept trial

BACKGROUND

Intravenous fluids are often used in the treatment of sepsis. The better strategy regarding fluid volume is debated, but preliminary data in patients with septic shock or sepsis-related hypotension favor restrictive fluid administration. We describe the protocol and statistical analysis plan for the Restrictive Fluid Administration vs. Standard of Care in Emergency Department Sepsis Patients (REFACED Sepsis)-a multicenter, randomized clinical proof-of-concept trial. The aim of the REFACED Sepsis trial is to test if a restrictive intravenous fluid protocol in emergency department patients with sepsis without shock is feasible and decreases the intravenous fluid volume administered in comparison to standard care.

METHODS

This is an investigator-initiated, multicenter, randomized, parallel-group, open-labeled, feasibility trial investigating volumes of crystalloid fluid within 24 h in 124 patients with sepsis without shock enrolled at three emergency departments in the Central Denmark Region. Patients are allocated to two different intravenous fluid regimens: a restrictive approach using four trigger criteria for fluid administration vs. standard care. The primary, feasibility outcome is total intravenous, crystalloid fluid volume within 24 h, and key secondary outcomes include protocol violations, total fluids (intravenous and oral) within 24 h, and serious adverse reactions and suspected unexpected serious adverse reactions. Status: The trial started in November 2021, and the last patient is anticipated to be included in January 2022.

DISCUSSION

Sepsis is very common in emergency department patients and fluid administration is very frequently administered in these patients. However, the evidence to guide fluid administration is very sparse. This feasibility trial will be the foundation for a potential future large-scale trial investigating restrictive vs. standard fluid administration in patients with sepsis.

TRIAL REGISTRATION

EudraCT number: 2021-000224-35 (date: 2021 May 03), ClinicalTrials.gov number: NCT05076435 (date: 2021 October 13), Committee on Health Research Ethics - Central Denmark Region: 1-10-72-163-21 (date: 2021 June 28).

A Standardized Step-by-Step Approach for the Diagnosis and Treatment of Sepsis

Sepsis is the major culprit of death among critically ill patients who are hospitalized in intensive care units (ICUs). Although sepsis-related mortality is steadily declining year-by-year due to the continuous understanding of the pathophysiological mechanism on sepsis and improvement of the bundle treatment, sepsis-associated hospitalization is rising worldwide. Surviving Sepsis Campaign (SSC) guidelines are continuously updating, while their content is extremely complex and comprehensive for a precisely implementation in clinical practice. As a consequence, a standardized step-by-step approach for the diagnosis and treatment of sepsis is particularly important. In the present study, we proposed a standardized step-by-step approach for the diagnosis and treatment of sepsis using our daily clinical experience and the latest researches, which is close to clinical practice and is easy to implement. The proposed approach may assist clinicians to more effectively diagnose and treat septic patients and avoid the emergence of adverse clinical outcomes.

Feasibility of conservative fluid administration and deresuscitation compared with usual care in critical illness: the Role of Active Deresuscitation After Resuscitation-2 (RADAR-2) randomised clinical trial

PURPOSE

Fluid overload is common in critical illness and is associated with mortality. This study investigated the feasibility of a randomised trial comparing conservative fluid administration and deresuscitation (active removal of accumulated fluid using diuretics or ultrafiltration) with usual care in critical illness.

METHODS

Open-label, parallel-group, allocation-concealed randomised clinical feasibility trial. Mechanically ventilated adult patients expected to require critical care beyond the next calendar day were enrolled between 24 and 48 h following admission to the intensive care unit (ICU). Patients were randomised to either a 2-stage fluid strategy comprising conservative fluid administration and, if fluid overload was present, active deresuscitation, or usual care. The primary endpoint was fluid balance in the 24 h up to the start of study day 3. Secondary endpoints included cumulative fluid balance, mortality, and duration of mechanical ventilation.

RESULTS

One hundred and eighty patients were randomised. After withdrawal of 1 patient, 89 patients assigned to the intervention were compared with 90 patients assigned to the usual care group. The mean plus standard deviation (SD) 24-h fluid balance up to study day 3 was lower in the intervention group (- 840 ± 1746 mL) than the usual care group (+ 130 ± 1401 mL; P < 0.01). Cumulative fluid balance was lower in the intervention group at days 3 and 5. Overall, clinical outcomes did not differ significantly between the two groups, although the point estimate for 30-day mortality favoured the usual care group [intervention arm: 19 of 90 (21.6%) versus usual care: 14 of 89 (15.6%), P = 0.32]. Baseline imbalances between groups and lack of statistical power limit interpretation of clinical outcomes.

CONCLUSIONS

A strategy of conservative fluid administration and active deresuscitation is feasible, reduces fluid balance compared with usual care, and may cause benefit or harm. In view of wide variations in contemporary clinical practice, large, adequately powered trials investigating the clinical effectiveness of conservative fluid strategies in critically ill patients are warranted.

Combining fluids and vasopressors: A magic potion?

Early detection and prompt reversal of sepsis-induced tissue hypoperfusion are key elements while treating patients with septic shock. Fluid administration is widely accepted as the first-line therapy followed by vasopressor use in persistently hypotensive patients or in those with insufficient arterial pressure to ensure adequate tissue perfusion. Recent evidence suggests a beneficial effect of combining fluids with vasopressors in the early phase of sepsis. Compared with fluids alone, combining fluids and vasopressors increases mean systemic pressure and venous return and corrects hypotension better. This approach also limits fluid overload, which is an independent factor of poor outcomes in sepsis. It produces less hemodilution than fluids alone. As a consequence of these effects, combined treatment may improve outcomes in septic shock patients.