Liberal Versus Restrictive Intravenous Fluid Therapy for Early Septic Shock: Rationale for a Randomized Trial

Year in Review 2023: Noteworthy Literature in Cardiothoracic Critical Care

This article reviews noteworthy investigations and society recommendations published in 2023 relevant to the care of critically ill cardiothoracic surgical patients. We reviewed 3,214 articles to identify 18 publications that add to the existing literature across a variety of topics including resuscitation, nutrition, antibiotic management, extracorporeal membrane oxygenation (ECMO), neurologic care following cardiac arrest, coagulopathy and transfusion, steroids in pulmonary infections, and updated guidelines in the management of acute respiratory distress syndrome (ARDS).

Does Point-of-Care Ultrasound Affect Fluid Resuscitation Volume in Patients with Septic Shock: A Retrospective Review

Background

Fixed, large volume resuscitation with intravenous fluids (IVFs) in septic shock can cause inadvertent hypervolemia, increased medical interventions, and death when unguided by point-of-care ultrasound (POCUS). The primary study objective was to evaluate whether total IVF volume differs for emergency department (ED) septic shock patients receiving POCUS versus no POCUS.

Methods

We conducted a retrospective observational cohort study from 7/1/2018 to 8/31/2021 of atraumatic adult ED patients with septic shock. We agreed upon a priori variables and defined septic shock as lactate ≥4 and hypotension (SBP <90 or MAP <65). A sample size of 300 patients would provide 85% power to detect an IVF difference of 500 milliliters between POCUS and non-POCUS cohorts. Data are reported as frequencies, median (IQR), and associations from bivariate logistic models.

Results

304 patients met criteria and 26% (78/304) underwent POCUS. Cardiac POCUS demonstrated reduced ejection fraction in 15.4% of patients. Lung ultrasound showed normal findings in 53% of patients. The POCUS vs. non-POCUS cohorts had statistically significant differences for the following variables: higher median lactate (6.7 [IQR 5.2-8.7] vs. 5.6], p = 0.003), lower systolic blood pressure (77.5 [IQR 61-86] vs. 85.0, p < 0.001), more vasopressor use (51% vs. 34%, p = 0.006), and more positive pressure ventilation (38% vs. 24%, p = 0.017). However, there were no statistically significant differences between POCUS and non-POCUS cohorts in total IVF volume ml/kg (33.02 vs. 32.1, p = 0.47), new oxygen requirement (68% vs. 59%, p = 0.16), ED death (3% vs. 4%, p = 0.15), or hospital death (31% vs. 27%, p = 0.48). There were similar distributions of lactate, total fluids, and vasopressors in patients with CHF and severe renal failure.

Conclusions

Among ED patients with septic shock, POCUS was more likely to be used in sicker patients. Patients who had POCUS were given similar volume of crystalloids although these patients were more critically ill. There were no differences in new oxygen requirement or mortality in the POCUS group compared to the non-POCUS group.

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.

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.

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.

Hemodynamic management of septic shock: beyond the Surviving Sepsis Campaign guidelines

Although the Surviving Sepsis Campaign guidelines provide standardized and generalized guidance, they are less individualized. This review focuses on recent updates in the hemodynamic management of septic shock. Monitoring and intervention for septic shock should be personalized according to the phase of shock. In the salvage phase, fluid resuscitation and vasopressors should be given to provide life-saving tissue perfusion. During the optimization phase, tissue perfusion should be optimized. In the stabilization and de-escalation phases, minimal fluid infusion and safe fluid removal should be performed, respectively, while preserving organ perfusion. There is controversy surrounding the use of restrictive versus liberal fluid strategies after initial resuscitation. Fluid administration after initial resuscitation should depend upon the patient's fluid responsiveness and requires individualized management. A number of dynamic tests have been proposed to monitor fluid responsiveness, which can help clinicians decide whether to give fluid or not. The optimal timing for the initiation of vasopressor agents is unknown. Recent data suggest that early vasopressor initiation should be considered. Inotropes can be considered in patients with decreased cardiac contractility associated with impaired tissue perfusion despite adequate volume status and arterial blood pressure. Venoarterial extracorporeal membrane oxygenation should be considered for refractory septic shock with severe cardiac systolic dysfunction.

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.

Fluid Resuscitation in Septic Patients

Sepsis is a life-threatening organ failure caused by a dysregulated response to infection. Fluid resuscitation and vasopressors are used to maintain systolic blood pressure and organ perfusion. Fluid resuscitation can be done with liberal or restricted fluids as well as colloids or crystalloid fluids. This review analyses the evidence for the use of liberal or restrictive fluids and colloids or crystalloids for the management of sepsis. A methodical search was conducted across PubMed, Cochrane Library, and ScienceDirect, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines were followed for this study. Randomized controlled trials and retrospective observational studies were included in this study. Liberal and restrictive fluid strategies were found to be comparable in efficacy, but restrictive fluid regimens had the added benefit of a lower incidence of fluid overload. Balanced crystalloids were safer and more effective when compared to normal saline. Albumin replacement was found to be safe and showed efficacy in reducing mortality in patients with sepsis and septic shock.

Restrictive versus Liberal Rate of Extracorporeal Volume Removal Evaluation in Acute Kidney Injury (RELIEVE-AKI): a pilot clinical trial protocol

INTRODUCTION

Observational studies have linked slower and faster net ultrafiltration (UFNET) rates during kidney replacement therapy (KRT) with mortality in critically ill patients with acute kidney injury (AKI) and fluid overload. To inform the design of a larger randomised trial of patient-centered outcomes, we conduct a feasibility study to examine restrictive and liberal approaches to UFNET during continuous KRT (CKRT).

METHODS AND ANALYSIS

This study is an investigator-initiated, unblinded, 2-arm, comparative-effectiveness, stepped-wedged, cluster randomised trial among 112 critically ill patients with AKI treated with CKRT in 10 intensive care units (ICUs) across 2 hospital systems. In the first 6 months, all ICUs started with a liberal UFNET rate strategy. Thereafter, one ICU is randomised to the restrictive UFNET rate strategy every 2 months. In the liberal group, the UFNET rate is maintained between 2.0 and 5.0 mL/kg/hour; in the restrictive group, the UFNET rate is maintained between 0.5 and 1.5 mL/kg/hour. The three coprimary feasibility outcomes are (1) between-group separation in mean delivered UFNET rates; (2) protocol adherence; and (3) patient recruitment rate. Secondary outcomes include daily and cumulative fluid balance, KRT and mechanical ventilation duration, organ failure-free days, ICU and hospital length of stay, hospital mortality and KRT dependence at hospital discharge. Safety endpoints include haemodynamics, electrolyte imbalance, CKRT circuit issues, organ dysfunction related to fluid overload, secondary infections and thrombotic and haematological complications.

ETHICS AND DISSEMINATION

The University of Pittsburgh Human Research Protection Office approved the study, and an independent Data and Safety Monitoring Board monitors the study. A grant from the United States National Institute of Diabetes and Digestive and Kidney Diseases sponsors the study. The trial results will be submitted for publication in peer-reviewed journals and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

This trial has been prospectively registered with clinicaltrials.gov (NCT05306964). Protocol version identifier and date: 1.5; 13 June 2023.

Emerging concepts in the care of patients with cirrhosis and septic shock

Septic shock impacts approximately 6% of hospitalized patients with cirrhosis and is associated with high rates of morbidity and mortality. Although a number of landmark clinical trials have paved the way for incremental improvements in the diagnosis and management of septic shock in the general population, patients with cirrhosis have largely been excluded from these studies and critical knowledge gaps continue to impact the care of these individuals. In this review, we discuss nuances in the care of patients with cirrhosis and septic shock using a pathophysiology-based approach. We illustrate that septic shock may be challenging to diagnose in this population in the context of factors such as chronic hypotension, impaired lactate metabolism, and concomitant hepatic encephalopathy. Furthermore, we demonstrate that the application of routine interventions such as intravenous fluids, vasopressors, antibiotics, and steroids should be carefully considered among those with decompensated cirrhosis in light of hemodynamic, metabolic, hormonal, and immunologic disturbances. We propose that future research should include and characterize patients with cirrhosis in a systematic manner, and clinical practice guidelines may need to be refined accordingly.

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.

The effect of gravity-induced preload change on the venous excess ultrasound (VExUS) score and internal jugular vein Doppler in healthy volunteers

BACKGROUND

The venous excess ultrasound (VExUS) score is a multi-organ Doppler approach to assess venous congestion. Despite growing use of VExUS in research and clinical practice, other veins can be visualized to assess for venous hypertension, which may overcome acquisition barriers of the VExUS exam. In this pilot, observational study, we used a wearable Doppler ultrasound to assess the relationship between jugular venous Doppler and the VExUS score under different preload conditions. We hypothesized that jugular Doppler morphology would accurately distinguish preload conditions, that it would most closely relate to the hepatic venous Doppler morphology in the fully supine position and that the VExUS score would be influenced by preload condition.

RESULTS

We recruited 15 healthy volunteers with no cardiovascular history. Preload change was achieved using a tilt-table with three positions: supine, fully upright, and 30-degree head-down tilt. In each position, a VExUS score was performed; furthermore, inferior vena collapsibility and sphericity index were calculated. At the same time, jugular venous Doppler was captured by a novel, wireless, wearable ultrasound system. A continuous jugular venous Doppler morphology was 96% accurate for detecting the low preload condition. The jugular venous Doppler morphology was highly correlated with the hepatic vein, but only in the supine position. Gravitational position did not significantly affect the sphericity index or the VExUS score.

CONCLUSIONS

The jugular vein Doppler morphology was able to accurately distinguish low from high preload conditions in healthy volunteers. Comparisons between VExUS Doppler morphologies and other veins should occur in the supine position when gravitational pressure gradients are minimized; finally, different preload conditions in healthy subjects did not affect the VExUS score.

Fluid management in septic patients with pulmonary hypertension, review of the literature

The management of sepsis in patients with pulmonary hypertension (PH) is challenging due to significant conflicting goals of management and complex hemodynamics. As PH progresses, the ability of right heart to perfuse lungs at a normal central venous pressure (CVP) is impaired. Elevated pulmonary vascular pressure, due to pulmonary vasoconstriction and vascular remodeling, opposes blood flow through lungs thus limiting the ability of right ventricle (RV) to increase cardiac output (CO) and maintain adequate oxygen delivery to tissue. In sepsis without PH, avoidance of volume depletion with intravascular volume replacement, followed by vasopressor therapy if hypoperfusion persists, remains the cornerstone of therapy. Intravenous fluid (IVF) resuscitation based on individualized hemodynamic assessment can help improve the prognosis of critically ill patients. This is accomplished by optimizing CO by maintaining adequate preload, afterload and contractility. Particular challenges in patients with PH include RV failure as a result of pressure and volume overload, gas exchange abnormalities, and managing IVF and diuretic use. Suggested approaches to remedy these difficulties include early recognition of symptoms associated with pressure and volume overload, intravascular volume management strategies and serial lab monitoring to assess electrolytes and renal function.

Sepsis-associated acute kidney injury: consensus report of the 28th Acute Disease Quality Initiative workgroup

Sepsis-associated acute kidney injury (SA-AKI) is common in critically ill patients and is strongly associated with adverse outcomes, including an increased risk of chronic kidney disease, cardiovascular events and death. The pathophysiology of SA-AKI remains elusive, although microcirculatory dysfunction, cellular metabolic reprogramming and dysregulated inflammatory responses have been implicated in preclinical studies. SA-AKI is best defined as the occurrence of AKI within 7 days of sepsis onset (diagnosed according to Kidney Disease Improving Global Outcome criteria and Sepsis 3 criteria, respectively). Improving outcomes in SA-AKI is challenging, as patients can present with either clinical or subclinical AKI. Early identification of patients at risk of AKI, or at risk of progressing to severe and/or persistent AKI, is crucial to the timely initiation of adequate supportive measures, including limiting further insults to the kidney. Accordingly, the discovery of biomarkers associated with AKI that can aid in early diagnosis is an area of intensive investigation. Additionally, high-quality evidence on best-practice care of patients with AKI, sepsis and SA-AKI has continued to accrue. Although specific therapeutic options are limited, several clinical trials have evaluated the use of care bundles and extracorporeal techniques as potential therapeutic approaches. Here we provide graded recommendations for managing SA-AKI and highlight priorities for future research.

Early Restrictive or Liberal Fluid Management for Sepsis-Induced Hypotension

BACKGROUND

Intravenous fluids and vasopressor agents are commonly used in early resuscitation of patients with sepsis, but comparative data for prioritizing their delivery are limited.

METHODS

In an unblinded superiority trial conducted at 60 U.S. centers, we randomly assigned patients to either a restrictive fluid strategy (prioritizing vasopressors and lower intravenous fluid volumes) or a liberal fluid strategy (prioritizing higher volumes of intravenous fluids before vasopressor use) for a 24-hour period. Randomization occurred within 4 hours after a patient met the criteria for sepsis-induced hypotension refractory to initial treatment with 1 to 3 liters of intravenous fluid. We hypothesized that all-cause mortality before discharge home by day 90 (primary outcome) would be lower with a restrictive fluid strategy than with a liberal fluid strategy. Safety was also assessed.

RESULTS

A total of 1563 patients were enrolled, with 782 assigned to the restrictive fluid group and 781 to the liberal fluid group. Resuscitation therapies that were administered during the 24-hour protocol period differed between the two groups; less intravenous fluid was administered in the restrictive fluid group than in the liberal fluid group (difference of medians, -2134 ml; 95% confidence interval [CI], -2318 to -1949), whereas the restrictive fluid group had earlier, more prevalent, and longer duration of vasopressor use. Death from any cause before discharge home by day 90 occurred in 109 patients (14.0%) in the restrictive fluid group and in 116 patients (14.9%) in the liberal fluid group (estimated difference, -0.9 percentage points; 95% CI, -4.4 to 2.6; P = 0.61); 5 patients in the restrictive fluid group and 4 patients in the liberal fluid group had their data censored (lost to follow-up). The number of reported serious adverse events was similar in the two groups.

CONCLUSIONS

Among patients with sepsis-induced hypotension, the restrictive fluid strategy that was used in this trial did not result in significantly lower (or higher) mortality before discharge home by day 90 than the liberal fluid strategy. (Funded by the National Heart, Lung, and Blood Institute; CLOVERS ClinicalTrials.gov number, NCT03434028.).

Resuscitation in the First 3 Hours of Sepsis-Induced Hypotension Varies by Patient and Hospital Factors

Patient and hospital factors affects how we resuscitate patients in the first 3 hours of sepsis-induced hypotension.

OBJECTIVES

To evaluate variability in compliance to the 3-hour surviving sepsis campaign (SSC) bundle and explore the association of early compliance with subsequent shock and in-hospital mortality.

DESIGN

Retrospective cohort study between September 2017 and February 2018.

SETTING

Thirty-four academic medical centers.

PARTICIPANTS

A subgroup sepsis-induced hypotensive patients from a larger shock cohort study.

MAIN OUTCOMES AND MEASURES

Compliance to SSC bundle that was defined as receiving appropriate antibiotics, 30 mL/kg of crystalloid or initiation of vasopressors, and lactate, obtained in the first 3 hours following sepsis-induced hypotension.

RESULTS

We included 977 patients with septic-induced hypotension. Bundle compliance was 43.8%, with the lowest compliance to fluid or vasopressor components (56%). Patients with high Sequential Organ Failure Assessment scores and physiologic assessments were more likely to receive compliant care, as were patients with sepsis-induced hypotension onset in the emergency department (ED) or admitted to mixed medical-surgical ICUs. SSC compliance was not associated with in-hospital mortality (adjusted odds ratio, 0.72; 95% CI, 0.47-1.10). The site-to-site variability contributed to SSC compliance (intraclass correlation coefficient [ICC], 0.15; 95% CI, 0.07-0.3) but not in-hospital mortality (ICC, 0.02; 95% CI, 0.001-0.24). Most patients remained in shock after 3 hours of resuscitation (SSC compliant 81.1% and noncompliant 53.7%). Mortality was higher among patients who were persistently hypotensive after 3 hours of resuscitation for both the SSC compliant (persistent hypotension 37% vs not hypotensive 27.2%; p = 0.094) and noncompliant (30.1% vs 18.2%; p = 0.001, respectively).

CONCLUSIONS AND RELEVANCE

Patients with a higher severity of illness and sepsis-induced hypotension identified in the ED were more likely to receive SSC-compliant care. SSC compliance was not associated with in-hospital mortality after adjusting for patient- and hospital-level differences. Higher mortality is seen among those who remain in shock after initial resuscitation, regardless of SSC compliance.

How Would You Resuscitate This Patient With Septic Shock? : Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Sepsis is a potentially life-threatening systemic dysregulatory response to infection, and septic shock occurs when sepsis leads to systemic vasodilation and subsequent tissue hypoperfusion. The Surviving Sepsis Campaign published updated guidelines in 2021 on the management of sepsis and septic shock. Here, in the context of a patient with septic shock, 2 critical care specialists discuss and debate conditional guideline recommendations on using lactate to guide resuscitation, the use of balanced crystalloids versus normal saline, and the use of corticosteroids.

Effect of prehospital transportation on 24-h fluid volume, a post hoc analysis of a multicenter, prospective, observational study on fluid volumes in patients with suspected infection

Introduction

Infections, including sepsis, are leading causes of death and fluid administration is part of the treatment. The optimal fluid therapy remains controversial. If the patient is transported by Emergency Medical Services (EMS), fluids can be initiated during transportation, which may result in increased overall fluid administration and fluid overload, which may be harmful. The aim of the study was to investigate the effect of EMS transportation on 24-h fluid administration in patients with suspected infection.

Methods

This is a post hoc study of a prospective, multicenter, observational study, conducted in three Danish Emergency Departments (EDs), 20 January-2 March 2020, aiming at describing fluid administration in patients with suspected infection. Patients were stratified into the groups: simple infection or sepsis, in accordance with SEPSIS-3-guidelines. The primary outcome of the current study was 24-h total fluid volume (oral and intravenous) stratified by transportation mode to the EDs.

Main results

Total 24-h fluids were registered for 734 patients. Patients with simple infection or sepsis arriving by EMS (n = 388, 54%) received mean 3,774 ml (standard deviation [SD]: 1900) and non-EMS received 3,627 ml (SD: 1568); mean difference (MD) was 303 ml [95% CI: 32; 573] adjusted for age, site, and total SOFA-score. Patients brought in by EMS received more intravenous fluids (MD: 621 ml [95% CI: 378; 864]) and less oral fluids (MD: -474 ml [95% CI: -616; -333]) than non-EMS patients.

Conclusion

Patients transported by EMS received more intravenous fluids and less oral fluids but overall, more fluid in total in the first 24-h than non-EMS after adjusting for age, site and SOFA-score.

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.

Prediction of septic and hypovolemic shock in intensive care unit patients using machine learning

OBJECTIVE

To create and validate a model for predicting septic or hypovolemic shock from easily obtainable variables collected from patients at admission to an intensive care unit.

METHODS

A predictive modeling study with concurrent cohort data was conducted in a hospital in the interior of northeastern Brazil. Patients aged 18 years or older who were not using vasoactive drugs on the day of admission and were hospitalized from November 2020 to July 2021 were included. The Decision Tree, Random Forest, AdaBoost, Gradient Boosting and XGBoost classification algorithms were tested for use in building the model. The validation method used was k-fold cross validation. The evaluation metrics used were recall, precision and area under the Receiver Operating Characteristic curve.

RESULTS

A total of 720 patients were used to create and validate the model. The models showed high predictive capacity with areas under the Receiver Operating Characteristic curve of 0.979; 0.999; 0.980; 0.998 and 1.00 for the Decision Tree, Random Forest, AdaBoost, Gradient Boosting and XGBoost algorithms, respectively.

CONCLUSION

The predictive model created and validated showed a high ability to predict septic and hypovolemic shock from the time of admission of patients to the intensive care unit.

Restrictive fluids versus standard care in adults with sepsis in the emergency department (REFACED): A multicenter, randomized feasibility trial

BACKGROUND

Fluid treatment in sepsis is a challenge and clinical equipoise exists regarding intravenous (IV) volumes. We aimed to determine whether a 24-h protocol restricting IV fluid was feasible in adult patients with sepsis without shock presenting to the emergency department (ED).

METHODS

The REFACED Sepsis trial is an investigator-initiated, multicenter, randomized, open-label, feasibility trial, assigning sepsis patients without shock to 24 h of restrictive, crystal IV fluid administration or standard care. In the IV fluid restriction group fluid boluses were only permitted if predefined criteria for hypoperfusion occurred. Standard care was at the discretion of the treating team. The primary outcome was total IV crystalloid fluid volumes at 24 h after randomization. Secondary outcomes included total fluid volumes, feasibility measures, and patient-centered outcomes.

RESULTS

We included 123 patients (restrictive 61 patients and standard care 62 patients) in the primary analysis. A total of 32% (95% confidence interval [CI] 28%-37%) of eligible patients meeting all inclusion criteria and no exclusion criteria were included. At 24 h, the mean (±SD) IV crystalloid fluid volumes were 562 (±1076) ml versus 1370 (±1438) ml in the restrictive versus standard care group (mean difference -801 ml, 95% CI -1257 to -345 ml, p = 0.001). Protocol violations occurred in 21 (34%) patients in the fluid-restrictive group. There were no differences between groups in adverse events, use of mechanical ventilation or vasopressors, acute kidney failure, length of stay, or mortality.

CONCLUSIONS

A protocol restricting IV crystalloid fluids in ED patients with sepsis reduced 24-h fluid volumes compared to standard care. A future trial powered toward patient-centered outcomes appears feasible.

Effective hemodynamic monitoring

Hemodynamic monitoring is the centerpiece of patient monitoring in acute care settings. Its effectiveness in terms of improved patient outcomes is difficult to quantify. This review focused on effectiveness of monitoring-linked resuscitation strategies from: (1) process-specific monitoring that allows for non-specific prevention of new onset cardiovascular insufficiency (CVI) in perioperative care. Such goal-directed therapy is associated with decreased perioperative complications and length of stay in high-risk surgery patients. (2) Patient-specific personalized resuscitation approaches for CVI. These approaches including dynamic measures to define volume responsiveness and vasomotor tone, limiting less fluid administration and vasopressor duration, reduced length of care. (3) Hemodynamic monitoring to predict future CVI using machine learning approaches. These approaches presently focus on predicting hypotension. Future clinical trials assessing hemodynamic monitoring need to focus on process-specific monitoring based on modifying therapeutic interventions known to improve patient-centered outcomes.

Challenges With Using a Weight-Based Approach to Bolus Fluid Dosing in Obese Critically Ill Patients

At least 30 mL/kg of crystalloid fluid administration within the first 3 hours of resuscitation is suggested by the current Surviving Sepsis Campaign guidelines for management of sepsis and septic shock. This commentary discusses the challenges with using a weight-based approach to bolus fluid dosing during the early phase of resuscitation of adult, obese patients. Based on the available literature, arguments can be made for the use of either ideal or adjusted body weight for weight-based fluid dosing, but there are concerns with fluid overload if using actual body weight to dose patients with more severe forms of obesity.

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.

The Effect of Fluid Initiation Timing on Sepsis Mortality: A Meta-Analysis

OBJECTIVE

Current guidelines suggest the immediate initiation of crystalloid for sepsis-induced hypoperfusion but note that supporting evidence is low quality. The aim of this study is to examine the effect of timing of fluid initiation on mortality for adults with sepsis.

DATA SOURCES

Two authors independently reviewed relevant articles and extracted study details from PubMed, Scopus, Cochrane, Google Scholar, and previous relevant systematic reviews from 1-1-2000 to 1-6-2022. Registered with PROSPERO (CRD42021245431) and bias assessed using CLARITY.

STUDY SELECTION

A minimum of severe sepsis (Sepsis-2) or sepsis (Sepsis-3) for patients ≥18 years old. Fluid initiation timing ranging from prehospital to 120 min within sepsis onset defined as "early" initiation.

DATA EXTRACTION

Included studies providing mortality-based odds ratios (or comparable) adjusting for confounders or prospective trials.

DATA SYNTHESIS

From 1643 citations, five retrospective cohort studies were included (n = 20,209) with in-hospital mortality of 21.8%. A pooled analysis (odds ratio = OR [95% CI]) did not observe an impact on mortality for the early initiation of fluids among all patients, OR = 0.79 [0.62-1.02]; heterogeneity: I² = 86% [70-94%], but when studies analyzed cases of hypotension where available, a survival benefit was observed, OR = 0.74 [0.61-0.90]. Initiation of fluids in two prehospital studies did not impact mortality, OR = 0.82 [0.27-2.43]. However, both prehospital cohorts observed benefit among hypotensive patients individually, although heterogenous results precluded significance when pooled, OR = 0.50 [0.21-1.18]. Three hospital-based studies with initiation stratified at 30, 100, and 120 min, observed survival benefit both individually and when pooled, OR = 0.78 [0.63-0.97]. No differences were observed between prehospital versus hospital subgroups.

CONCLUSION

This meta-analysis supports the guideline recommendations for early fluid initiation once sepsis is recognized, especially in cases of hypotension. Findings are limited by the small number, heterogeneity, and retrospective nature of available studies. Further retrospective investigations may be worthwhile as randomized studies on fluid initiation are unlikely.

Nursing Implications of the Updated 2021 Surviving Sepsis Campaign Guidelines

Sepsis is a life-threatening illness that affects millions of people worldwide. Early recognition and timely treatment are essential for decreasing mortality from sepsis. The Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021, the fifth iteration of the guidelines, was released in October 2021 and includes 93 recommendations for the management of sepsis. The evidence-based guidelines include recommendations and rationales for screening and early treatment, initial resuscitation, mean arterial pressure targets, admission to intensive care, management of infection, hemodynamic monitoring, ventilation, and additional therapies. A new section addresses long-term outcomes and goals of care. This article presents several recommendations, changes, and updates in the 2021 guidelines and highlights the important contributions nurses have in delivering timely and evidence-based care to patients with sepsis. Recommendations may be for or against an intervention, according to the evidence. Although many recommendations are unchanged, several new recommendations directly affect nursing care and may require specialized training (eg, venovenous extracorporeal membrane oxygenation). The newest section, long-term outcomes and goals of care, is aimed at using available resources to provide care that is aligned with the patient and the patient's family through goals-of-care discussions and shared decision-making. Interventions aimed at improving recovery across the continuum of care should include attention to long-term outcomes. Nurses are essential in identifying patients with sepsis, administering and assessing response to treatment, supporting the patient and family, and limiting sequelae from sepsis. This article highlights the 2021 recommendations that influence nursing care for patients with sepsis.

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.

Sepsis Management for the Nephrologist

The definition of sepsis has evolved significantly over the past three decades. Today, sepsis is defined as a dysregulated host immune response to microbial invasion leading to end organ dysfunction. Septic shock is characterized by hypotension requiring vasopressors after adequate fluid resuscitation with elevated lactate. Early recognition and intervention remain hallmarks for sepsis management. We addressed the current literature and assimilated thought regarding optimum initial resuscitation of the patient with sepsis. A nuanced understanding of the physiology of lactate is provided in our review. Physiologic and practical knowledge of steroid and vasopressor therapy for sepsis is crucial and addressed. As blood purification may interest the nephrologist treating sepsis, we have also added a brief discussion of its status.

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.

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).

Modeling of Usual Care: Vasopressor Initiation for Sepsis With Hypotension

Usual care regarding vasopressor initiation is ill-defined. We aimed to develop a quantitative “dynamic practice” model for usual care in the emergency department (ED) regarding the timing of vasopressor initiation in sepsis. In a retrospective study of 589 septic patients with hypotension in an urban tertiary care center ED, we developed a multi-variable model that distinguishes between patients who did and did not subsequently receive sustained (>24 h) vasopressor therapy. Candidate predictors were vital signs, intravenous fluid (IVF) volumes, laboratory measurements, and elapsed time from triage computed at timepoints leading up to the final decision timepoint of either vasopressor initiation or ED hypotension resolution without vasopressors. A model with six independently significant covariates (respiratory rate, Glasgow Coma Scale score, SBP, SpO₂, administered IVF, and elapsed time) achieved a C-statistic of 0.78 in a held-out test set at the final decision timepoint, demonstrating the ability to reliably model usual care for vasopressor initiation for hypotensive septic patients. The included variables measured depth of hypotension, extent of disease severity and organ dysfunction. At an operating point of 90% specificity, the model identified a minority of patients (39%) more than an hour before actual vasopressor initiation, during which time a median of 2,250 (IQR 1,200–3,300) mL of IVF was administered. This single-center analysis shows the feasibility of a quantitative, objective tool for describing usual care. Dynamic practice models may help assess when management was atypical; such tools may also be useful for designing and interpreting clinical trials.

Association of ICU Admission and Outcomes in Sepsis and Acute Respiratory Failure

Rationale: Many decisions to admit patients to the ICU are not grounded in evidence regarding who benefits from such triage, straining ICU capacity and limiting its cost-effectiveness. Objectives: To measure the benefits of ICU admission for patients with sepsis or acute respiratory failure. Methods: At 27 United States hospitals across two health systems from 2013 to 2018, we performed a retrospective cohort study using two-stage instrumental variable quantile regression with a strong instrument (hospital capacity strain) governing ICU versus ward admission among high-acuity patients (i.e., laboratory-based acute physiology score v2 ⩾ 100) with sepsis and/or acute respiratory failure who did not require mechanical ventilation or vasopressors in the emergency department. Measurements and Main Results: Among patients with sepsis (n = 90,150), admission to the ICU was associated with a 1.32-day longer hospital length of stay (95% confidence interval [CI], 1.01-1.63; P < 0.001) (when treating deaths as equivalent to long lengths of stay) and higher in-hospital mortality (odds ratio, 1.48; 95% CI, 1.13-1.88; P = 0.004). Among patients with respiratory failure (n = 45,339), admission to the ICU was associated with a 0.82-day shorter hospital length of stay (95% CI, -1.17 to -0.46; P < 0.001) and reduced in-hospital mortality (odds ratio, 0.75; 95% CI, 0.57-0.96; P = 0.04). In sensitivity analyses of length of stay, excluding, ignoring, or censoring death, results were similar in sepsis but not in respiratory failure. In subgroup analyses, harms of ICU admission for patients with sepsis were concentrated among older patients and those with fewer comorbidities, and the benefits of ICU admission for patients with respiratory failure were concentrated among older patients, highest-acuity patients, and those with more comorbidities. Conclusions: Among high-acuity patients with sepsis who did not require life support in the emergency department, initial admission to the ward, compared with the ICU, was associated with shorter length of stay and improved survival, whereas among patients with acute respiratory failure, triage to the ICU compared with the ward was associated with improved survival.

Patterns of Vasoactive Agent Initiation Among Children With Septic Shock in the Pediatric Emergency Department

OBJECTIVE

The aim of the study was to describe patterns of initiation (and factors associated with delayed initiation) of vasoactive agents among pediatric emergency patients with septic shock.

METHODS

Patients with septic shock from November 2013 to September 2016 who had a vasoactive agent initiated for documented hypotension were classified as "guideline adherent" (hypotensive following the final fluid bolus and had vasoactive agents initiated within 60 minutes) or "delayed initiation" (hypotensive after the final bolus and were initiated on vasoactive agents after >60 minutes). Patient-level factors (demographics, presence of underlying condition including central venous catheter, and markers of disease severity) and outcomes (mortality, length of stay) were compared between groups.

RESULTS

Of the 37 eligible patients, 17 received vasoactive agents within "guideline adherent" timelines and 10 were "delayed initiation." An additional group was identified as "transient responders"; these patients were normotensive after a final fluid bolus but developed hypotension and were initiated on a vasoactive agent within 2 hours after admission (n = 10). We found no significant difference between the "guideline adherent" and "delayed initiation" groups according to patient-level factors or outcomes; "transient responders" were more likely than other groups to have a central venous catheter and had longer lengths of stay.

CONCLUSIONS

Although there are perceived barriers to vasoactive agent initiation, we found no significant difference in patient-level factors between the timely and delayed groups. This study also identified a group of patients labeled as transient responders, who initially appeared volume responsive but who required vasoactive support within several hours. This cohort requires further study.

Shock Management Without Formal Fluid Responsiveness Assessment: A Retrospective Analysis of Fluid Responsiveness and Its Outcomes

BACKGROUND

In order to quantify fluid administration and evaluate the clinical consequences of conservative fluid management without hemodynamic monitoring in undifferentiated shock, we analyzed previously collected data from a study of carotid Doppler monitoring as a predictor of fluid responsiveness (FR).

METHODS

This study was a retrospective analysis of data collected from a single tertiary academic center from a previous study. Seventy-four patients were included for post-hoc analysis, and 52 of them were identified as fluid responsive (cardiac output increase > 10% with passive leg raise) according to NICOMTM bioreactance monitoring (Cheetah Medical, Newton Center, MA, USA). Treating teams provided standard of care conservative fluid resuscitation but were blinded to independently performed FR testing results. Outcomes were compared between fluid responsive and fluid non-responsive patients. Primary outcome measures were volume fluids administered and net fluid balance 24- and 72-hour post-FR assessment. Secondary outcome measures included change in vasopressor requirements, mean peak lactate levels, length of hospital/intensive care unit stay, acute respiratory failure, hemodialysis requirement, and durations of vasopressors and mechanical ventilation.

RESULTS

Mean fluids administered within 72 hours were similar between fluid non-responsive and fluid responsive patients (139 mL/kg [95% confidence interval [CI]: 102.00-175.00] vs. 136 mL/kg [95% CI: 113.00-158.00], p = 0.92, respectively). We observed an insignificant trend toward higher 28-day mortality among fluid non-responsive patients (36% vs. 19%, p = 0.14). Volume of fluids administered significantly correlated with adverse outcomes such as increased hemodialysis requirements (32 patients, 43%), (odds ratio [OR] = 1.7200, p = 0.0018). Subgroup analysis suggested administering ≥ 30 mL/kg fluids to fluid responsive patients had a trend toward increased mortality (25% vs. 0%, p = 0.09) and a significant increase in hemodialysis (55% vs. 17%, p = 0.024).

CONCLUSIONS

Without formal FR assessment, similar amounts of total fluids were administered in both fluid responsive and non-responsive patients. As greater volumes of intravenous fluids administered were associated with adverse outcomes, we suggest that dedicated FR assessment may be a beneficial utility in early shock resuscitation.

Optimizing Fluid Resuscitation and Preventing Fluid Overload in Patients with Septic Shock

Intravenous fluid administration remains an important component in the care of patients with septic shock. A common error in the treatment of septic shock is the use of excessive fluid in an effort to overcome both hypovolemia and vasoplegia. While fluids are necessary to help correct the intravascular depletion, vasopressors should be concomitantly administered to address vasoplegia. Excessive fluid administration is associated with worse outcomes in septic shock, so great care should be taken when deciding how much fluid to give these vulnerable patients. Simple or strict "recipes" which mandate an exact amount of fluid to administer, even when weight based, are not associated with better outcomes and therefore should be avoided. Determining the correct amount of fluid requires the clinician to repeatedly assess and consider multiple variables, including the fluid deficit, organ dysfunction, tolerance of additional fluid, and overall trajectory of the shock state. Dynamic indices, often involving the interaction between the cardiovascular and respiratory systems, appear to be superior to traditional static indices such as central venous pressure for assessing fluid responsiveness. Point-of-care ultrasound offers the bedside clinician a multitude of applications which are useful in determining fluid administration in septic shock. In summary, prevention of fluid overload in septic shock patients is extremely important, and requires the careful attention of the entire critical care team.

Evidence for the Application of Sepsis Bundles in 2021

Sepsis represents a severe condition that predisposes patients to a high risk of death if its progression is not ended. As with other time-dependent conditions, the performance of determinant interventions has led to significant survival benefits and quality-of-care improvements in acute emergency care. Thus, the initial interventions in sepsis are a cornerstone for prognosis in most patients. Even though the evidence supporting the hour-1 bundle is perfectible, real-life application of thoughtful and organized sepsis care has improved survival and quality of care in settings promoting compliance to evidence-based treatments. Current evidence for implementing the Surviving Sepsis Campaign bundles for early sepsis management is moving forward to better approaches as more substantial evidence evolves.

Should Vasopressors Be Started Early in Septic Shock?

Sepsis can influence blood volume, its distribution, vascular tone, and cardiac function. Persistent hypotension or the need for vasopressors after volume resuscitation is part of the definition of septic shock. Since increased positive fluid balance has been associated with increased morbidity and mortality in sepsis, timing of vasopressors in the treatment of septic shock seems crucial. However, conclusive evidence on timing and sequence of interventions with the goal to restore tissue perfusion is lacking. The aim of this narrative review is to depict the pathophysiology of hypotension in sepsis, evaluate how common interventions to treat hypotension interfere with physiology, and to give a resume of the results from clinical studies focusing on targets and timing of vasopressor in sepsis. The majority of studies comparing early versus late administration of vasopressors in septic shock are rather small, single-center, and retrospective. The range of "early" is between 1 and 12 hours. The available studies suggest a mean arterial pressure of 60 to 65 mm Hg as a threshold for increased risk of morbidity and mortality, whereas higher blood pressure targets do not seem to add further benefits. The data, albeit mostly from observational studies, speak for combining vasopressors with fluids rather "early" in the treatment of septic shock (within a 0-3-hour window). Nevertheless, the optimal resuscitation strategy should take into account the source of infection, the pathophysiology, the time and clinical course preceding the diagnosis of sepsis, and also comorbidities and sepsis-induced organ dysfunction.

Twenty-four-hour fluid administration in emergency department patients with suspected infection: A multicenter, prospective, observational study

BACKGROUND

To describe 24-hour fluid administration in emergency department (ED) patients with suspected infection.

METHODS

A prospective, multicenter, observational study conducted in three Danish hospitals, January 20 to March 2, 2020. We included consecutive adult ED patients with suspected infection (drawing of blood culture and/or intravenous antibiotic administration within 6 hours of admission). Oral and intravenous fluids were registered for 24 hours.

PRIMARY OUTCOME

24-hour total fluid volume. We used linear regression to investigate patient and disease characteristics' effect on 24-hour fluids and to estimate the proportion of the variance in fluid administration explained by potential predictors.

RESULTS

734 patients had 24-hour fluids available: 387 patients had simple infection, 339 sepsis, eight septic shock. Mean total 24-hour fluid volumes were 3656 mL (standard deviation [SD]:1675), 3762 mL (SD: 1839), and 6080 mL (SD: 3978) for the groups, respectively. Fluid volumes varied markedly. Increasing age (mean difference [MD]: 60-79 years: -470 mL [95% CI: -789, -150], +80 years; -974 mL [95% CI: -1307, -640]), do-not-resuscitate orders (MD: -466 mL [95% CI: -797, -135]), and preexisting atrial fibrillation (MD: -367 mL [95% CI: -661, -72) were associated with less fluid. Systolic blood pressure < 100 mmHg (MD: 1182 mL [95% CI: 820, 1543]), mean arterial pressure < 65 mmHg (MD: 1317 mL [95% CI: 770, 1864]), lactate ≥ 2 mmol/L (MD: 655 mL [95% CI: 306, 1005]), heart rate > 120 min (MD: 566 [95% CI: 169, 962]), low (MD: 1963 mL [95% CI: 813, 3112]) and high temperature (MD: 489 mL [95% CI: 234, 742]), SOFA score > 5 (MD: 1005 mL [95% CI: 501, 510]), and new-onset atrial fibrillation (MD: 498 mL [95% CI: 30, 965]) were associated with more fluid. Clinical variables explained 37% of fluid variation among patients.

CONCLUSIONS

Patients with simple infection and sepsis received equal fluid volumes. Fluid volumes varied markedly, a variation that was partly explained by clinical characteristics.

Initial fluid resuscitation (30 mL/kg) in patients with septic shock: More or less?

OBJECTIVES

The 2018 Surviving Sepsis Campaign (SSC) recommends rapid administration of 30 mL/kg crystalloid fluids for hypotension or lactate ≥4 mmol/L in patients with septic shock; however, there is limited evidence to support this recommendation. The purpose of this study was to examine the relationship between initial fluid resuscitation doses and prognosis in patients with septic shock.

METHODS

This was a multicenter prospective observational study of adult patients with septic shock who were admitted to four intensive care units (ICUs) in a total of three Jiangsu Province teaching hospitals over a 3-year span from May 8, 2018, to June 15, 2021. Each enrolled patients with septic shock was categorized into the low-volume (below 20 mL/kg fluid), medium-volume (20-30 mL/kg fluid) or high-volume (above 30 mL/kg fluid) fluid group according to the initial infusion dose given for fluid resuscitation. Various demographic attributes and other variables were collected from medical records. Logistic regression and Kaplan-Meier curve analysis were used to determine the relationship between initial fluid resuscitation doses and patient outcomes.

MEASUREMENTS AND MAIN RESULTS

A total of 302 patients who presented to the ICU were diagnosed with septic shock. The 28-day mortality was highest in the high-volume group (48.3%) and lowest in the medium-volume group (26.3%, P < 0.05). Patients who completed 30 mL/kg initial fluid resuscitation in the first 1-2 h had the lowest 28-day mortality rate (22.8%, P < 0.05). Logistic regression showed that a medium initial fluid volume dose was an independent protective factor, with the odds ratio (OR) indicating significantly decreased mortality (OR, 0.507; 95% confidence interval, 0.310-0.828; P = 0.007; P < 0.05). A Kaplan-Meier curve stratified by initial fluid resuscitation dose was constructed for the probability of 28-day mortality. The medium-volume fluid group showed a significantly lower 28-day mortality rate than the high-volume group or the low-volume group (log-rank test, P = 0.0016).

CONCLUSION

In septic shock patients, an initial fluid resuscitation rate of 20-30 mL/kg within the first hour may be associated with reduced 28-day mortality; however, this result needs to be confirmed by further high-quality randomized controlled clinical trials.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR-OOC-17013223. Registered 2 November 2017, http://www.chictr.org.cn/showproj.aspx?proj=22674.

Effect of rapid fluid administration on the prognosis of septic shock patients with isolated hyperlactatemia: A prospective multicenter observational study

BACKGROUND

We aimed to investigate the association between initial fluid resuscitation in septic shock patients with isolated hyperlactatemia and outcomes.

METHODS

This multicenter prospective study was conducted using the data from the Korean Shock Society registry. Patients diagnosed with isolated hyperlactatemia between October 2015 and December 2018 were included and divided into those who received 30 mL/kg of fluid within 3 or 6 h and those who did not receive. The primary outcome was in-hospital mortality; the secondary outcomes were intensive care unit (ICU) admission, length of ICU stay, mechanical ventilation, and renal replacement therapy (RRT).

RESULTS

A total of 608 patients were included in our analysis. The administration of 30 mL/kg crystalloid within 3 or 6 h was not significantly associated with in-hospital mortality in multivariable logistic regression analysis ([OR, 0.8; 95% CI, 0.52-1.23, p = 0.31], [OR, 0.96; 95% CI, 0.59-1.57, p = 0.88], respectively). The administration of 30 mL/kg crystalloid within 3-h was not significantly associated with mechanical ventilation and RRT ([OR, 1.19; 95% CI, 0.77-1.84, p = 0.44], [OR, 1.2; 95% CI, 0.7-2.04, p = 0.5], respectively). However, the administration of 30 mL/kg crystalloid within 6 h was associated with higher ICU admission and RRT ([OR, 1.57; 95% CI, 1.07-2.28, p = 0.02], [OR, 2.08; 95% CI, 1.19-3.66, p = 0.01], respectively).

CONCLUSIONS

Initial fluid resuscitation of 30 mL/kg within 3 or 6 h was neither associated with an increased or decreased in-hospital mortality in septic shock patients with isolated hyperlactatemia.

Impact of Clinician Recognition of Acute Respiratory Distress Syndrome on Evidenced-Based Interventions in the Medical ICU

Acute respiratory distress syndrome is underrecognized in the ICU, but it remains uncertain if acute respiratory distress syndrome recognition affects evidence-based acute respiratory distress syndrome care in the modern era. We sought to determine the rate of clinician-recognized acute respiratory distress syndrome in an academic medical ICU and understand how clinician-recognized-acute respiratory distress syndrome affects clinical care and patient-centered outcomes.

DESIGN

Observational cohort study.

SETTING

Single medical ICU at an academic tertiary-care hospital.

PATIENTS

Nine hundred seventy-seven critically ill adults (381 with expert-adjudicated acute respiratory distress syndrome) enrolled from 2006 to 2015.

INTERVENTIONS

Clinician-recognized-acute respiratory distress syndrome was identified using an electronic keyword search of clinical notes in the electronic health record. We assessed the classification performance of clinician-recognized acute respiratory distress syndrome for identifying expert-adjudicated acute respiratory distress syndrome. We also compared differences in ventilator settings, diuretic prescriptions, and cumulative fluid balance between clinician-recognized acute respiratory distress syndrome and unrecognized acute respiratory distress syndrome.

MEASUREMENTS AND MAIN RESULTS

Overall, clinician-recognized-acute respiratory distress syndrome had a sensitivity of 47.5%, specificity 91.1%, positive predictive value 77.4%, and negative predictive value 73.1% for expert-adjudicated acute respiratory distress syndrome. Among the 381 expert-adjudicated acute respiratory distress syndrome cases, we did not observe any differences in ventilator tidal volumes between clinician-recognized-acute respiratory distress syndrome and unrecognized acute respiratory distress syndrome, but clinician-recognized-acute respiratory distress syndrome patients had a more negative cumulative fluid balance (mean difference, -781 mL; 95% CI, [-1,846 to +283]) and were more likely to receive diuretics (49.3% vs 35.7%, p = 0.02). There were no differences in mortality, ICU length of stay, or ventilator-free days.

CONCLUSIONS

Acute respiratory distress syndrome recognition was low in this single-center study. Although acute respiratory distress syndrome recognition was not associated with lower ventilator volumes, it was associated with differences in behaviors related to fluid management. These findings have implications for the design of future studies promoting evidence-based acute respiratory distress syndrome interventions in the ICU.

Analysis of Noninvasive Ventilation in Subjects With Sepsis and Acute Respiratory Failure

BACKGROUND

Acute respiratory failure is among the sequelae of complications that can develop in response to severe sepsis. Research into sepsis-related respiratory failure has focused on ARDS and invasive mechanical ventilation. We studied the factors associated with success and failure of noninvasive ventilation (NIV) in the treatment of sepsis-related acute respiratory failure.

METHODS

This retrospective study included 136 subjects with a diagnosis of acute respiratory failure and intrapulmonary or extrapulmonary sepsis who were placed on NIV. Subjects were divided into 2 groups based on the need for intubation from NIV: NIV failure (n = 70) and NIV success (n = 66). Demographic, clinical, and outcome data were collected and compared between groups, with the development of multivariate models to predict NIV failure and mortality.

RESULTS

The overall NIV failure rate in subjects with a diagnosis of sepsis was 51%. There were no between-group differences in demographic or baseline characteristics. However, there were significant differences in clinical variables, with higher SOFA scores (NIV failure: 6.4 [± 3.0] vs NIV success: 4.9 [± 2.1]; P = .002), 2nd lactate levels (NIV failure: 2.6 [1.7 - 4.3] vs NIV success: 1.9 [1.4 - 2.6] mmol/L; P = .007), and initial NIV [Formula: see text] settings (NIV failure: 0.50 [0.40 - 0.70] vs NIV failure: 0.40 [0.35 - 0.50]; P = .003) in subjects who failed NIV. There were also more subjects in the NIV failure group who had a lactate ≥ 4 mmol/L prior to NIV start compared to those who succeeded on NIV (33% vs 15%, P = .02). At NIV start, subjects in the NIV failure group had lower mean arterial pressure (85 mm Hg [IQR 74-96] vs 91.7 mm Hg [IQR 78-108], P = .042) and Glasgow coma scale scores (14 [IQR 13-15] vs 15 [IQR 14-15], P < .002), while fewer subjects in the NIV failure group received a fluid bolus in the 24 h prior to NIV start (33% vs 53%, P = .02) or had signs of volume overload (36% vs 64%, P < .001). Multivariate analysis indicated that age (odds ratio 1.05 [95% CI 1.01-1.09], P = .02), SOFA score (odds ratio 1.49 [95% CI 1.15-1.94], P = .002), first systolic blood pressure (odds ratio 0.97 [95% CI 0.95-0.99], P = .02), signs of volume overload (odds ratio 0.23 [95% CI 0.07-0.68], P = .008], fluids prior to NIV (odds ratio 0.08 [95% CI 0.02-0.31], P < .001), and initial [Formula: see text] on NIV (odds ratio 1.04 [95% CI 1.01-1.08, P = .002) independently predicted NIV failure with an area under the curve of 0.88. Only NIV failure independently predicted death in multivariate analysis (area under the curve = 0.70).

CONCLUSIONS

NIV failure in sepsis-related acute respiratory failure was independently predicted by patient acuity, first systolic blood pressure after sepsis alert, initial [Formula: see text] settings on NIV, fluid resuscitation, and signs of volume overload. However, only NIV failure independently predicted death in this cohort of subjects.

Most emergency department patients meeting sepsis criteria are not diagnosed with sepsis at discharge

OBJECTIVES

Effective sepsis resuscitation depends on useful criteria for prompt identification of eligible patients. These criteria should reliably predict a discharge diagnosis of sepsis, ensuring that interventions are triggered for those who need it while avoiding potentially harmful interventions in those who do not. We sought to determine the proportion of patients meeting sepsis criteria in the emergency department (ED) that was ultimately diagnosed with sepsis and to quantify the subset of nonseptic patients with risk factors for harm from fluid resuscitation.

METHODS

This retrospective cohort study of adult ED patients at a tertiary academic medical center included vital signs and laboratory results from the first 6 hours, plus administration of intravenous antibiotics, to determine if patients met 2016 Sepsis-3 consensus criteria. If these patients also had hypotension and lactic acidosis, we categorized them as Sepsis-3 plus shock. We used discharge ICD-9 codes to determine if patients were ultimately diagnosed with sepsis.

RESULTS

Over 8 years, 3,121 ED patients met 2016 Sepsis-3 criteria in the first 6 hours. Of these, only 25% and 48% met explicit and implicit criteria for a discharge diagnosis of sepsis. Of 1,032 patients with Sepsis-3 plus shock, 48% and 62% met explicit and implicit criteria. Overall, 60% to 75% of ED patients meeting Sepsis-3 criteria with or without shock did not receive a sepsis discharge diagnosis. At least one plausible risk factor for harm from large-volume fluid resuscitation was identified among 19% to 36% of patients meeting sepsis criteria in the ED but not ultimately diagnosed with sepsis at discharge.

CONCLUSIONS

Most patients meeting sepsis criteria in the ED were not diagnosed with sepsis at discharge. Urgent treatment bundles triggered by consensus criteria in the early phase of ED care may be administered to several patients without sepsis, potentially exposing some to interventions of uncertain benefit and possible harm.