Fluid Overload

Risk factors and predictive models for postoperative surgical site infection in patients with massive hemorrhage

Background

This study aimed to identify risk factors associated with postoperative surgical site infection (SSI) in patients experiencing massive hemorrhage and develop a predictive model.

Methods

A retrospective analysis of 121 orthopedic surgery patients and experienced massive hemorrhage was conducted. According to postoperative SSI occurrence, the patients were divided into two groups: the infection group (n = 12) and the non-infection group (n = 109). Clinical data were collected, and a predictive model was developed using logistic regression analysis in patients with massive hemorrhage.

Results

Independent risk factors for postoperative SSI included ASA grade, urine volume, and type 2 diabetes. An area under the curve for the prediction of postoperative SSI based on the Receiver Operating Characteristic (ROC) curve for the risk score was 0.916.

Conclusions

Patients with a urine volume of ≥3.49 ml/kg/h, higher ASA grade, and type 2 diabetes are at an increased risk of developing postoperative SSI after experiencing massive hemorrhage.

Level of evidence

Level III.

Relationship Between Cumulative Fluid Balance and the Degree of Venous Congestion According to VExUS Score in Critically Ill Patients in a General Intensive Care Unit

OBJECTIVES

The Venous Excess Ultrasound Score (VExUS) assesses venous congestion using point-of-care ultrasound. While validated to predict acute kidney injury, its relationship with cumulative fluid balance and clinical edema remains unclear. This study aimed to evaluate these associations 72 hours after intensive care unit (ICU) admission.

METHODS

This analytical observational cohort study included adult ICU patients with Foley catheters inserted at admission for fluid balance quantification. Patients on dialysis or with cirrhosis or abdominal hypertension were excluded. The correlation between cumulative fluid balance, edema clinical grade, and VExUS grade was analyzed. Multivariate analysis identified factors associated with significant venous congestion (VExUS grade ≥2), with statistical significance set at P < .05.

RESULTS

A total of 123 patients were included, with a mean age of 60 years (SD ±19.2); 59.3% were male. Venous congestion (VExUS grade ≥1) was observed in 36.5% of patients, despite an average cumulative fluid balance of +0.88 L. Each liter of positive cumulative fluid balance increased the risk of significant congestion (VExUS grade ≥2) by 31% (OR = 1.31; 95% CI: 1.07-1.60). The correlation between clinical edema (Godet scale) and VExUS grade was weak (Spearman rho = 0.27), and clinical edema was not associated with significant congestion (OR = 3.22; 95% CI: 0.77-13.56).

CONCLUSIONS

In ICU patients, fluid overload is an early contributor to significant venous congestion (VExUS grade ≥2) but does not correlate with clinical edema grades, highlighting the limitations of clinical edema in assessing venous congestion.

Predictive accuracy of changes in the inferior vena cava diameter for predicting fluid responsiveness in patients with sepsis: A systematic review and meta-analysis

BACKGROUND

Existing guidelines emphasize the importance of initial fluid resuscitation therapy in sepsis management. However, in previous meta-analyses, there have been inconsistencies in differentiating between spontaneously breathing and mechanically ventilated septic patients.

OBJECTIVE

To consolidate the literature on the predictive accuracy of changes in the inferior vena cava diameter (∆IVC) for fluid responsiveness in septic patients.

METHODS

The Embase, Web of Science, Cochrane Library, MEDLINE, PubMed, Wanfang, China National Knowledge Infrastructure (CNKI), Chinese Biomedical (CBM) and VIP (Weipu) databases were comprehensively searched. Statistical analyses were performed with Stata 15.0 software and Meta-DiSc 1.4.

RESULTS

Twenty-one research studies were deemed suitable for inclusion. The sensitivity and specificity of ∆ IVC were 0.84 (95% CI 0.76, 0.90) and 0.87 (95% CI 0.80, 0.91), respectively. With respect to the distensibility of the inferior vena cava (dIVC), the sensitivity was 0.79 (95% CI 0.68, 0.86), and the specificity was 0.82 (95% CI 0.73, 0.89). For collapsibility of the inferior vena cava (cIVC), the sensitivity and specificity values were 0.92 (95% CI 0.83, 0.96) and 0.93 (95% CI 0.86, 0.97), respectively.

CONCLUSION

The results indicated that ∆IVC is as a dependable marker for fluid responsiveness in sepsis patients. dIVC and cIVC also exhibited high levels of accuracy in predicting fluid responsiveness in septic patients.

Association of net ultrafiltration intensity and clinical outcomes among critically ill patients receiving continuous renal replacement therapy: A systematic review, meta-analysis, and trial sequential analysis

BACKGROUND

Net ultrafiltration (UFnet) has been used in the fluid management of critically ill patients undergoing continuous renal replacement therapy for an extended duration. Despite its widespread application, the correlation between UFnet intensity and clinical outcomes remains controversial.

METHODS

Electronic databases (PubMed, Embase, Web of Science, and the Cochrane database) were searched from inception to November 30, 2023. All possible studies that examined the following outcomes were included: all-cause mortality, recovery of kidney function, and length of hospital stay.

RESULTS

A total of 6209 patients from six cohort studies were included. There was no significant association observed between UFnet intensity and either mortality (odds ratio [OR] = 0.90, 95% confidence interval [CI] = 0.68-1.21, p = 0.49, I2 = 84%) or renal recovery (OR = 0.96, 95% CI = 0.57-1.61, p = 0.87, I2 = 75%) among critically ill patients. However, a high intensity of UFnet was associated with lower mortality in patients with acute kidney injury (AKI) (OR = 0.73, 95% CI = 0.59-0.90, p = 0.004, I2 = 67%). Furthermore, the study revealed a noteworthy correlation between a high UFnet intensity and a longer length of hospital stay (weighted mean difference = 3.34 d, 95% CI = 2.64-4.03, p2 = 0%).

CONCLUSIONS

The association between UFnet intensity and mortality or renal recovery in critically ill patients is insufficient. However, a high UFnet intensity is associated with an increasing length of hospital stay among critically ill patients.

Net albumin leakage in patients in the ICU with suspected sepsis. A prospective analysis using mass balance calculations

INTRODUCTION

Albumin kinetics in septic shock have been extensively studied, but clinical recommendations remain weak. An increased transcapillary escape rate (TER) of albumin has been demonstrated, though TER does not account for lymphatic return. Mass balance calculations, considering lymphatic return, have been used to assess net albumin leakage (NAL) in major surgery but not in sepsis.

OBJECTIVES

This study aimed to evaluate NAL in ten ICU patients with suspected sepsis, hypothesizing a net positive leakage. Secondary aims included investigating associations between NAL and fluid overload, glycocalyx shedding products, and cytokines, as well as identifying factors associated with it.

METHODS

This prospective, observational study included ten patients within twelve hours of ICU admission for suspected sepsis at Karolinska University Hospital Huddinge. Albumin, hematocrit, and hemoglobin levels were sampled at 0, 1, 2, 4, 8, and 24 h. NAL was estimated using mass balance calculations, comparing proportional changes in albumin and hemoglobin concentrations over time, adjusted for albumin and hemoglobin infusions and losses. A proportionally greater decrease or smaller increase in albumin compared to hemoglobin indicated NAL, representing the net leakage from the circulation to the interstitium minus lymphatic return.

RESULTS

Over 24 h, patients exhibited a net positive albumin leakage to the interstitium of 8 ± 10 g (p = 0.029). NAL showed no correlation with glycocalyx shedding products or fluid overload but had a weak correlation with interleukin-6 and interleukin-8 in the first 4 h. Albumin infusions appeared to increase net leakage.

CONCLUSION

This study demonstrated a net positive albumin leakage of 8 ± 10 g over 24 h in ICU patients with suspected sepsis, with a weak early correlation to pro-inflammatory cytokines but no significant link to fluid balance or glycocalyx shedding. Notably, albumin infusions were associated with increased net leakage.

Cracking the Code of AKI: Evaluating the Predictive Power of VExUS Scoring in Critically Ill Noncardiac Patients

Background

Numerous signs of venous congestion exist, but each has limitations. Previous studies have shown the utility of venous excess ultrasound (VExUS) scoring in predicting acute kidney injury (AKI) in patients postcardiac surgery. This study aimed to evaluate whether serial VExUS scoring could predict AKI in intensive care unit (ICU) patients without cardiac conditions.

Materials and methods

This single-center observational study was conducted in the main ICU of PGIMER, Chandigarh, India. Thirty patients with an inferior vena cava (IVC) diameter of ≥2 cm and a normal biventricular function were included. Serial VExUS scoring was performed on admission and daily for up to six days or until AKI developed, whichever occurred first.

Results

Among 30 participants, 22 (73.3%) developed AKI. In the AKI group, mean VExUS scores were 1.95 on day 2, 1.92 on day 3, and 3.0 on day 5 (p = 0.001, 0.003, and 0.002, respectively). A significant positive correlation was observed between VExUS scores and fluid balance on day 2 (ρ = 0.375, p = 0.041) and day 3 (ρ = 0.579, p = 0.006). Multivariate analysis showed no correlation between the VExUS score on day 2 and fluid balance, duration of mechanical ventilation, or ICU length of stay. No association was found between VExUS scores and 30-day mortality.

Conclusion

In critically ill noncardiac patients, VExUS scores do not predict AKI onset. However, higher daily fluid balance may moderately correlate with VExUS scores.

How to cite this article

Khan WA, Saini V, Goel A, Valiyaparambath A. Cracking the Code of AKI: Evaluating the Predictive Power of VExUS Scoring in Critically Ill Noncardiac Patients. Indian J Crit Care Med 2025;29(3):236-243.

Relevance of perioperative fluid dynamics in liver transplantation to acute kidney injury and patient outcomes: a cross-sectional survey

Background

Fluid administration is a critical component of perioperative management for liver transplant recipients, and excessive fluid infusion can lead to acute kidney injury (AKI) and poor patient outcomes.

Method

We conducted a cross-sectional survey on the fluid intake and output of adult liver transplant recipients over a 7-day period. The patients were divided into AKI and non-AKI groups. Multivariate logistic regression analyses were used to evaluate the association between fluid balance (FB) and AKI. A Kaplan-Meier survival analysis was performed to determine the survival of the recipient survival at 180 days.

Results

A total of 210 liver transplant recipients were included. The peak FB occurred on the second day after transplantation, which was higher than on the seventh day (0.3 [IQR, -0.2 to 0.8] L vs. -0.4 [IQR, -1.0 to 0.3] L, p < 0.001). The highest incidence of AKI was observed on the second day after transplantation and the lowest on the seventh day (52.4% vs. 15.4%, p < 0.001). Multivariate analysis showed that a cumulative FB > 1 L within the first 2 days postoperatively was an independent risk factor for AKI on the second day after liver transplantation (LT) (OR = 2.66, 95% CI, 1.31-5.41, p = 0.007). Survival analysis indicated significant differences in 180-day survival rates among patients with different grades of AKI [94.0% (grade 1) vs. 91.4% (grade 2) vs. 77.8% (grade 3), χ 2  = 12.93, p < 0.001].

Conclusion

There is a significant correlation between post-LT AKI and perioperative FB. Cumulative FB > 1 L in the first 2 days postoperatively is an independent risk factor for AKI on the second day after LT. AKI after LT is associated with a lower 180-day survival rate in patients.

Differences in the Evaluation of Malnutrition and Body Composition Using Bioelectrical Impedance Analysis, Nutritional Ultrasound, and Dual-Energy X-ray Absorptiometry in Patients with Heart Failure

BACKGROUND

Although malnutrition is frequently observed in patients with heart failure (HF), this diagnosis should be performed carefully since HF itself is associated with increased inflammatory activity, which affects body weight, functionality, and some nutritional parameters; thus, its isolated interpretation can erroneously identify surrogate markers of severity as markers of malnutrition. In this context, we aimed to evaluate the prevalence of malnutrition using different classification systems and perform a comprehensive nutritional evaluation to determine the reliability of different diagnostic techniques.

PATIENTS AND METHODS

Eighty-three patients with a recent hospital admission due to HF were evaluated. GLIM diagnosis criteria and subjective global assessment (SGA) were performed; a comprehensive anthropometric, functional, and biochemical nutritional evaluation was performed, in which bioelectrical impedance analysis (BIA), nutritional ultrasound, and dual-energy X-ray absorptiometry (DXA) were performed. Additionally, mortality and additional admissions due to HF were determined after a mean follow up of 18 months.

RESULTS

Malnutrition according to the GLIM criteria (54%) accurately distinguished patients with impaired functionality, lower lean mass, skeletal mass index, and appendicular muscle mass (BIA), as well as lower trunk fat mass, trunk lean mass, fat-free mass (DXA), and decreased albumin and increased C-reactive protein serum levels. According to SGA, there were significant changes in body composition parameters determined by BIA, muscle ultrasound, and functional tests between well-nourished patients and patients with risk of malnutrition (53.7%) or who had malnutrition (7.1%), but not when the last two groups were compared. BIA and DXA showed strong correlations when evaluating muscle and fat mass in HF patients, but correlations with nutritional ultrasound were limited, as well as functional tests. A multivariate analysis showed that no significant association was observed between body composition and mortality, but preperitoneal fat was associated with an increased risk of new hospital admissions (OR: 0.73).

CONCLUSIONS

GLIM criteria identified a lower percentage of patients with HF and malnutrition compared with SGA; thus, SGA could have a role in preventing malnutrition in HF patients. Nutritional evaluation with BIA and DXA in patients with HF showed reliable results of body composition parameters in HF, and both help with the diagnosis of malnutrition according to the GLIM or SGA criteria and could provide complementary information in some specific cases.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Unsupervised machine learning analysis to identify patterns of ICU medication use for fluid overload prediction

INTRODUCTION

Intravenous (IV) medications are a fundamental cause of fluid overload (FO) in the intensive care unit (ICU); however, the association between IV medication use (including volume), administration timing, and FO occurrence remains unclear.

METHODS

This retrospective cohort study included consecutive adults admitted to an ICU ≥72 hours with available fluid balance data. FO was defined as a positive fluid balance ≥7% of admission body weight within 72 hours of ICU admission. After reviewing medication administration record (MAR) data in three-hour periods, IV medication exposure was categorized into clusters using principal component analysis (PCA) and Restricted Boltzmann Machine (RBM). Medication regimens of patients with and without FO were compared within clusters to assess for temporal clusters associated with FO using the Wilcoxon rank sum test. Exploratory analyses of the medication cluster most associated with FO for medications frequently appearing and used in the first 24 hours was conducted.

RESULTS

FO occurred in 127/927 (13.7%) of the patients enrolled. Patients received a median (IQR) of 31 (13-65) discrete IV medication administrations over the 72-hour period. Across all 47,803 IV medication administrations, ten unique IV medication clusters were identified with 121-130 medications in each cluster. Among the ten clusters, cluster 7 had the greatest association with FO; the mean number of cluster 7 medications received was significantly greater in patients in the FO cohort compared to patients who did not experience FO (25.6 vs.10.9. p<0.0001). 51 of the 127 medications in cluster 7 (40.2%) appeared in > 5 separate 3-hour periods during the 72-hour study window. The most common cluster 7 medications included continuous infusions, antibiotics, and sedatives/analgesics. Addition of cluster 7 medications to a prediction model with APACHE II score and receipt of diuretics improved the ability for the model to predict fluid overload (AUROC 5.65, p =0.0004).

CONCLUSIONS

Using ML approaches, a unique IV medication cluster was strongly associated with FO. Incorporation of this cluster improved the ability to predict development of fluid overload in ICU patients compared with traditional prediction models. This method may be further developed into real-time clinical applications to improve early detection of adverse outcomes.

Delphi Process for Validation of Fluid Treatment Algorithm for Critically Ill Pediatric Trauma Patients

INTRODUCTION

While intravenous fluid therapy is essential to re-establishing volume status in children who have experienced trauma, aggressive resuscitation can lead to various complications. There remains a lack of consensus on whether pediatric trauma patients will benefit from a liberal or restrictive crystalloid resuscitation approach and how to optimally identify and transition between fluid phases.

METHODS

A panel was comprised of physicians with expertise in pediatric trauma, critical care, and emergency medicine. A three-round Delphi process was conducted via an online survey, with each round being followed by a live video conference. Experts agreed or disagreed with each aspect of the proposed fluid management algorithm on a five-level Likert scale. The group opinion level defined an algorithm parameter's acceptance or rejection with greater than 75% agreement resulting in acceptance and greater than 50% disagreement resulting in rejection. The remaining were discussed and re-presented in the next round.

RESULTS

Fourteen experts from five Level 1 pediatric trauma centers representing three subspecialties were included. Responses were received from 13/14 participants (93%). In round 1, 64% of the parameters were accepted, while the remaining 36% were discussed and re-presented. In round 2, 90% of the parameters were accepted. Following round 3, there was 100% acceptance by all the experts on the revised and final version of the algorithm.

CONCLUSIONS

We present a validated algorithm for intavenous fluid management in pediatric trauma patients that focuses on the de-escalation of fluids. Focusing on this time point of fluid therapy will help minimize iatrogenic complications of crystalloid fluids within this patient population.

Fluid Balance in Continuous Renal Replacement Therapy: Prescribing, Delivering, and Review

BACKGROUND

Historically IV and enteral fluids given during acute kidney injury (AKI) were restricted before the introduction of continuous renal replacement therapies (CRRTs) when more liberal fluids improved nutrition for the critically ill. However, fluid accumulation can occur when higher volumes each day are not considered in the fluid balance prescribing and the NET ultrafiltration (NUF) volume target.

KEY MESSAGES

The delivered hours of CRRT each day are vital for achievement of fluid balance and time off therapy makes the task more challenging. Clinicians inexperienced with CRRT make this aspect of AKI management a focus of rounding with senior oversight, clear communication, and "precision" a clinical target. Sepsis-associated AKI can be a complex patient where resuscitation and admission days are with a positive fluid load and replacement mind set. Subsequent days in ICU requires fluid regulation, removal, with a comprehensive multilayered assessment before prescribing the daily fluid balance target and the required hourly NET plasma water removal rate (NUF rate). Future machines may include advanced software, new alarms - display metrics, messages and association with machine learning and "AKI models" for setting, monitoring, and guaranteeing fluid removal. This could also link to current hardware such as on-line blood volume assessment with continuous haematocrit measurement.

SUMMARY

Fluid balance in the acutely ill is a challenge where forecasting and prediction are necessary. NUF rate and volume each hour should be tracked and adjusted to achieve the daily target. This requires human and machine connections.

[Application and control of intravenous fluids in German intensive care units : A national survey among critical care physicians]

BACKGROUND

The administration of intravenous fluids includes various indications, e.g., fluid replacement, nutritional therapy or as a solvent for drugs and is a common routine in the intensive care unit (ICU); however, overuse of intravenous fluids can lead to fluid overload, which can be associated with a poorer outcome in critically ill patients.

OBJECTIVE

The aim of this survey was to find out the current status of the use and management of intravenous fluids as well as the interprofessional cooperation involving clinical pharmacists on German ICUs.

METHODS

An online survey with 33 questions was developed. The answers of 62 participants from the Scientific Working Group on Intensive Care Medicine of the German Society for Anesthesiology and Intensive Care Medicine were evaluated.

RESULTS

Fluid overload occurs "frequently" in 62.9% (39/62) and "very frequently" in 9.7% (6/62) of the ICUs of respondents. An established standard for an infusion management system is unknown to 71.0% (44/62) of participants and 45.2% of the respondents stated that they did not have a patient data management system. In addition, the participants indicated how they define fluid overload. This was defined by the presence of edema by 50.9% (28/55) and by positive fluid balance by 30.9% (17/55). According to the participants septic patients (38/60; 63.3%) and cardiological/cardiac surgical patients (26/60; 43.3%) are most susceptible to the occurrence of fluid overload. Interprofessional collaboration among intensive care physicians, critical care nurses, and clinical pharmacists to optimize fluid therapy was described as "relevant" by 38.7% (24/62) and "very relevant" by 45.2% (28/62). Participants with clinical pharmacists on the wards (24/62; 38.7%) answered this question more often as "very relevant" with 62.5% (15/24).

CONCLUSION

Fluid overload is a frequent and relevant problem in German intensive care units. Yet there are few established standards in this area. There is also a lack of validated diagnostic parameters and a clear definition of fluid overload. These are required to ensure appropriate and effective treatment that is tailored to the patient and adapted to the respective situation. Intravenous fluids should be considered as drugs that may exert side effects or can be overdosed with severe adverse consequences for the patients. One approach to optimize fluid therapy could be achieved by a fluid stewardship corresponding to comparable established procedures of the antibiotic stewardship. In particular, fluid stewardship will contribute to drug safety of intravenous fluids profiting from joined expertise in a setting of interprofessional collaboration. An important principle of fluid stewardship is to consider intravenous fluids in the same way as medication in terms of their importance. Furthermore, more in-depth studies are needed to investigate the effects of interprofessional fluid stewardship in a prospective and controlled manner.

Fluid Status Assessment in Critically Ill Patients with COVID-19: A Retrospective Cohort Study

Fluid status (FS) is a diagnostic challenge in critically ill patients with COVID-19. Here, we compared parameters related to FS derived from cumulative fluid balance (CFB), bioelectrical impedance analysis (BIA) and venous congestion assessed by ultrasound (VExUS) to predict mortality. We retrospectively reviewed the medical records of individuals with severe pneumonia due to COVID-19 between July and November 2021 in a single center. Comorbidities, demographic, clinical and laboratory data as well as results from CFB, BIA and VExUS measurements were collected on admission and weekly afterwards for two consecutive evaluations. Seventy-nine patients were included, of which eighteen (14.2%) died. Abnormalities of FS were only identified by BIA. Extracellular water/total body water ratio (ECW/TBW) > 0.394 (overhydrated) by BIA was a good predictor of mortality (AUC = 0.78, 95% CI: 0.067-0.89). Mortality risk was higher in overhydrated patients (OR: 6.2, 95% CI: 1.2-32.6, p = 0.02) and in persistently overhydrated patients (OR: 9.57, 95% CI: 1.18-77.5, p = 0.03) even after adjustment to age, serum albumin and acute kidney injury (AKI) in stages 2-3. Time to death was shorter in overhydrated patients (HR: 2.82, 95% CI: 1.05-7.5, log-rank test p = 0.03). Abnormalities in FS associated with mortality were only identified by BIA in critically ill patients with COVID-19.

Improving mixed-integer temporal modeling by generating synthetic data using conditional generative adversarial networks: A case study of fluid overload prediction in the intensive care unit

OBJECTIVE

The challenge of mixed-integer temporal data, which is particularly prominent for medication use in the critically ill, limits the performance of predictive models. The purpose of this evaluation was to pilot test integrating synthetic data within an existing dataset of complex medication data to improve machine learning model prediction of fluid overload.

MATERIALS AND METHODS

This retrospective cohort study evaluated patients admitted to an ICU ≥ 72 h. Four machine learning algorithms to predict fluid overload after 48-72 h of ICU admission were developed using the original dataset. Then, two distinct synthetic data generation methodologies (synthetic minority over-sampling technique (SMOTE) and conditional tabular generative adversarial network (CTGAN)) were used to create synthetic data. Finally, a stacking ensemble technique designed to train a meta-learner was established. Models underwent training in three scenarios of varying qualities and quantities of datasets.

RESULTS

Training machine learning algorithms on the combined synthetic and original dataset overall increased the performance of the predictive models compared to training on the original dataset. The highest performing model was the meta-model trained on the combined dataset with 0.83 AUROC while it managed to significantly enhance the sensitivity across different training scenarios.

DISCUSSION

The integration of synthetically generated data is the first time such methods have been applied to ICU medication data and offers a promising solution to enhance the performance of machine learning models for fluid overload, which may be translated to other ICU outcomes. A meta-learner was able to make a trade-off between different performance metrics and improve the ability to identify the minority class.

Internal jugular vein collapsibility does not predict fluid responsiveness in spontaneously breathing patients after cardiac surgery

PURPOSE

The objective of our study was to evaluate the diagnostic accuracy of internal jugular vein (IJV) collapsibility as a predictor of fluid responsiveness in spontaneously breathing patients after cardiac surgery.

METHODS

In this prospective observational study, spontaneously breathing patients were enrolled on the first postoperative day after coronary artery bypass grafting. Hemodynamic data coupled with simultaneous ultrasound assessment of the IJV were collected at baseline and after passive leg raising test (PLR). Continuous cardiac index (CI), stroke volume (SV), and stroke volume variation (SVV) were assessed with FloTracTM/EV1000™. Fluid responsiveness was defined as an increase in CI ≥ 10% after PLR. We compared the differences in measured variables between fluid responders and non-responders and tested the ability of ultrasonographic IJV indices to predict fluid responsiveness.

RESULTS

Fifty-four patients were included in the study. Seventeen (31.5%) were fluid responders. The responders demonstrated significantly lower inspiratory and expiratory diameters of the IJV at baseline, but IJV collapsibility was comparable (P = 0.7). Using the cut-off point of 20%, IJV collapsibility predicted fluid responsiveness with a sensitivity of 76.5% and specificity of 38.9%, ROC AUC 0.55.

CONCLUSION

In spontaneously breathing patients after surgical coronary revascularisation, collapsibility of the internal jugular vein did not predict fluid responsiveness.

Machine learning vs. traditional regression analysis for fluid overload prediction in the ICU

Fluid overload, while common in the ICU and associated with serious sequelae, is hard to predict and may be influenced by ICU medication use. Machine learning (ML) approaches may offer advantages over traditional regression techniques to predict it. We compared the ability of traditional regression techniques and different ML-based modeling approaches to identify clinically meaningful fluid overload predictors. This was a retrospective, observational cohort study of adult patients admitted to an ICU ≥ 72 h between 10/1/2015 and 10/31/2020 with available fluid balance data. Models to predict fluid overload (a positive fluid balance ≥ 10% of the admission body weight) in the 48-72 h after ICU admission were created. Potential patient and medication fluid overload predictor variables (n = 28) were collected at either baseline or 24 h after ICU admission. The optimal traditional logistic regression model was created using backward selection. Supervised, classification-based ML models were trained and optimized, including a meta-modeling approach. Area under the receiver operating characteristic (AUROC), positive predictive value (PPV), and negative predictive value (NPV) were compared between the traditional and ML fluid prediction models. A total of 49 of the 391 (12.5%) patients developed fluid overload. Among the ML models, the XGBoost model had the highest performance (AUROC 0.78, PPV 0.27, NPV 0.94) for fluid overload prediction. The XGBoost model performed similarly to the final traditional logistic regression model (AUROC 0.70; PPV 0.20, NPV 0.94). Feature importance analysis revealed severity of illness scores and medication-related data were the most important predictors of fluid overload. In the context of our study, ML and traditional models appear to perform similarly to predict fluid overload in the ICU. Baseline severity of illness and ICU medication regimen complexity are important predictors of fluid overload.

Intraoperative hypotension and postoperative outcomes: a meta-analysis of randomised trials

INTRODUCTION

Intraoperative hypotension is associated with adverse postoperative outcomes; however these findings are supported only by observational studies. The aim of this meta-analysis of randomised trials was to compare the postoperative effects permissive management with targeted management of intraoperative blood pressure.

METHODS

We searched PubMed, Cochrane, and Embase up to June 2023 for studies comparing permissive (mean arterial pressure ≤60 mm Hg) with targeted (mean arterial pressure >60 mm Hg) intraoperative blood pressure management. Primary outcome was all-cause mortality at the longest follow-up available. Secondary outcomes were atrial fibrillation, myocardial infarction, acute kidney injury, delirium, stroke, number of patients requiring transfusion, time on mechanical ventilation, and length of hospital stay.

RESULTS

We included 10 randomised trials including a total of 9359 patients. Mortality was similar between permissive and targeted blood pressure management groups (89/4644 [1.9%] vs 99/4643 [2.1%], odds ratio 0.88, 95% confidence interval [CI], 0.65-1.18, P=0.38, I2=0% with nine studies included). Atrial fibrillation (102/3896 [2.6%] vs 130/3887 [3.3%] odds ratio 0.71, 95% CI 0.53-0.96, P=0.03, I2=0%), and length of hospital stay (mean difference -0.20 days, 95% CI -0.26 to -0.13, P<0.001, I2=0%) were reduced in the permissive management group. No significant differences were found in subgroup analysis for cardiac and noncardiac surgery.

CONCLUSION

Pooled randomised evidence shows that a target intraoperative mean arterial pressure ≤60 mm Hg is not associated with increased mortality; nevertheless it is surprisingly associated with a reduced rate of atrial fibrillation and of length of hospital stay.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO CRD42023393725.

The Importance of Optimal Hydration in Patients with Heart Failure-Not Always Too Much Fluid

Heart failure (HF) is a leading cause of morbidity and mortality and a major public health problem. Both overhydration and dehydration are non-physiological states of the body that can adversely affect human health. Congestion and residual congestion are common in patients hospitalized for HF and are associated with poor prognosis and high rates of rehospitalization. However, the clinical problem of dehydration is also prevalent in healthcare and community settings and is associated with increased morbidity and mortality. This article provides a comprehensive review of the issue of congestion and dehydration in HF, including HF guidelines, possible causes of dehydration in HF, confirmed and potential new diagnostic methods. In particular, a full database search on the relationship between dehydration and HF was performed and all available evidence in the literature was reviewed. The novel hypothesis of chronic subclinical hypohydration as a modifiable risk factor for HF is also discussed. It is concluded that maintaining euvolemia is the cornerstone of HF management. Physicians have to find a balance between decongestion therapy and the risk of dehydration.

Pulmonary oedema in the course of severe maternal outcome in South Africa: A cohort study combined with clinical audit

OBJECTIVES

To describe the incidence and outcomes of pulmonary oedema in women with severe maternal outcome during childbirth and identify possible modifiable factors through audit.

METHODS

All women with severe maternal outcome (maternal deaths or near misses) who were referred to Tygerberg referral hospital from health facilities in Metro East district, South Africa, during 2014-2015 were included. Women with severe maternal outcome and pulmonary oedema during pregnancy or childbirth were evaluated using three types of critical incident audit: criterion-based case review by one consultant gynaecologist, monodisciplinary critical incident audit by a team of gynaecologists, multidisciplinary audit with expert review from anaesthesiologists and cardiologists.

RESULTS

Of 32,161 pregnant women who gave birth in the study period, 399 (1.2%) women had severe maternal outcome and 72/399 (18.1%) had pulmonary oedema with a case fatality rate of 5.6% (4/72). Critical incident audit demonstrated that pre-eclampsia/HELLP-syndrome and chronic hypertension were the main conditions underlying pulmonary oedema (44/72, 61.1%). Administration of volumes of intravenous fluids in already sick women, undiagnosed underlying cardiac illness, administration of magnesium sulphate as part of pre-eclampsia management and oxytocin for augmentation of labour were identified as possible contributors to the pathophysiology of pulmonary oedema. Women-related factors (improved antenatal care attendance) and health care-related factors (earlier diagnosis and management) would potentially have improved maternal outcome.

CONCLUSIONS

Although pulmonary oedema in pregnancy is rare, among women with severe maternal outcome a considerable proportion had pulmonary oedema (18.1%). Audit identified options for prevention of pulmonary oedema and improved outcome. These included early detection and management of preeclampsia with close monitoring of fluid intake and cardiac evaluation in case of suspected pulmonary oedema. Therefore, a multidisciplinary clinical approach is recommended.

PASSIVE LEG RAISING-INDUCED CHANGES IN PEAK VELOCITY VARIATION OF LEFT VENTRICULAR OUTFLOW TRACT TO PREDICT FLUID RESPONSIVENESS IN POSTOPERATIVE CRITICALLY ILL ELDERLY PATIENTS

ABSTRACT

Background : Accurate prediction of fluid responsiveness is important for postoperative critically ill elderly patients. The objective of this study was to evaluate the predictive values of peak velocity variation (ΔVpeak) and passive leg raising (PLR)-induced changes in ΔVpeak (ΔVpeak PLR ) of the left ventricular outflow tract to predict fluid responsiveness in postoperative critically ill elderly patients. Method : Seventy-two postoperative elderly patients with acute circulatory failure who were mechanically ventilated with sinus rhythm were enrolled in our study. Pulse pressure variation (PPV), ΔVpeak, and stroke volume were collected at baseline and after PLR. An increase of >10% in stroke volume after PLR defined fluid responsiveness. Receiver operating characteristic curves and gray zones were constructed to assess the ability of ΔVpeak and ΔVpeak PLR to predict fluid responsiveness. Results : Thirty-two patients were fluid responders. The area under the receiver operating characteristic curves (AUC) for baseline PPV and ΔVpeak to predict fluid responsiveness was 0.768 (95% confidence interval [CI], 0.653-0.859; P < 0.001) and 0.899 (95% CI, 0.805-0.958; P < 0.001) with gray zones of 7.63% to 12.66% that included 41 patients (56.9%) and 9.92% to 13.46% that included 28 patients (38.9%). ΔPPV PLR predicted fluid responsiveness with an AUC of 0.909 (95% CI, 0.818-0.964; P < 0.001), and the gray zone was 1.49% to 2.93% and included 20 patients (27.8%). ΔVpeak PLR predicted fluid responsiveness with an AUC of 0.944 (95% CI, 0.863-0.984; P < 0.001), and the gray zone was 1.48% to 2.46% and included six patients (8.3%). Conclusions : Passive leg raising-induced changes in peak velocity variation of blood flow in the left ventricular outflow tract accurately predicted fluid responsiveness with a small gray zone in postoperative critically ill elderly patients.

RESPIRATORY VARIABILITY OF VALVULAR PEAK SYSTOLIC VELOCITY AS A NEW INDICATOR OF FLUID RESPONSIVENESS IN PATIENTS WITH SEPTIC SHOCK

ABSTRACT

Objective: The aim of this study was to evaluate the reliability and feasibility of pulse Doppler measurements of peak velocity respiratory variability of mitral and tricuspid valve rings during systole as new dynamic indicators of fluid responsiveness in patients with septic shock. Methods: Transthoracic echocardiography (TTE) was performed to measure the respiratory variability of aortic velocity-time integral (∆VTI), respiratory variability of tricuspid annulus systolic peak velocity (∆RVS), respiratory variability of mitral annulus systolic peak velocity (∆LVS), and other related indicators. Fluid responsiveness was defined as a 10% increase in cardiac output after fluid expansion, assessed by TTE. Results: A total of 33 patients with septic shock were enrolled in this study. First, there was no significant difference in the population characteristics between the fluid responsiveness positive group (n = 17) and the fluid responsiveness negative group (n = 16) ( P > 0.05). Second, Pearson correlation test showed that ∆RVS, ∆LVS, and TAPSE with the relative increase in cardiac output after fluid expansion ( R = 0.55, P = 0.001; R = 0.40, P = 0.02; R = 0.36, P = 0.041). Third, multiple logistic regression analysis demonstrated that ∆RVS, ∆LVS, and TAPSE were significantly correlated with fluid responsiveness in patients with septic shock. Fourth, receiver operating characteristic (ROC) curve analysis revealed that ∆VTI, ∆LVS, ∆RVS, and TAPSE had good predictive ability for fluid responsiveness in patients with septic shock. The area under the curve (AUC) of ∆VTI, ∆LVS, ∆RVS, and TAPSE for predicting fluid responsiveness was 0.952, 0.802, 0.822, and 0.713, respectively. The sensitivity (Se) values were 1.00, 0.73, 0.81, and 0.83, whereas the specificity (Sp) values were 0.84, 0.91, 0.76, and 0.67, respectively. The optimal thresholds were 0.128, 0.129, 0.130, and 13.9 mm, respectively. Conclusion: Tissue Doppler ultrasound evaluation of respiratory variability of mitral and tricuspid annular peak systolic velocity could be a feasible and reliable method for the simple assessment of fluid responsiveness in patients with septic shock.

Improving irregular temporal modeling by integrating synthetic data to the electronic medical record using conditional GANs: a case study of fluid overload prediction in the intensive care unit

Objective

The challenge of irregular temporal data, which is particularly prominent for medication use in the critically ill, limits the performance of predictive models. The purpose of this evaluation was to pilot test integrating synthetic data within an existing dataset of complex medication data to improve machine learning model prediction of fluid overload.

Materials and Methods

This retrospective cohort study evaluated patients admitted to an ICU ≥ 72 hours. Four machine learning algorithms to predict fluid overload after 48-72 hours of ICU admission were developed using the original dataset. Then, two distinct synthetic data generation methodologies (synthetic minority over-sampling technique (SMOTE) and conditional tabular generative adversarial network (CT-GAN)) were used to create synthetic data. Finally, a stacking ensemble technique designed to train a meta-learner was established. Models underwent training in three scenarios of varying qualities and quantities of datasets.

Results

Training machine learning algorithms on the combined synthetic and original dataset overall increased the performance of the predictive models compared to training on the original dataset. The highest performing model was the metamodel trained on the combined dataset with 0.83 AUROC while it managed to significantly enhance the sensitivity across different training scenarios.

Discussion

The integration of synthetically generated data is the first time such methods have been applied to ICU medication data and offers a promising solution to enhance the performance of machine learning models for fluid overload, which may be translated to other ICU outcomes. A meta-learner was able to make a trade-off between different performance metrics and improve the ability to identify the minority class.

Severe fluctuation in mean perfusion pressure is associated with increased risk of in-hospital mortality in critically ill patients with central venous pressure monitoring: A retrospective observational study

BACKGROUND

The mean perfusion pressure (MPP) was recently proposed to personalize tissue perfusion pressure management in critically ill patients. Severe fluctuation in MPP may be associated with adverse outcomes. We sought to determine if higher MPP variability was correlated with increased mortality in critically ill patients with CVP monitoring.

METHODS

We designed a retrospective observational study and analyzed data stored in the eICU Collaborative Research Database. Validation test was conducted in MIMIC-III database. The exposure was the coefficient of variation (CV) of MPP in the primary analyses, using the first 24 hours MPP data recorded within 72 hours in the first ICU stay. Primary endpoint was in-hospital mortality.

RESULTS

A total of 6,111 patients were included. The in-hospital mortality of 17.6% and the median MPP-CV was 12.3%. Non-survivors had significantly higher MPP-CV than survivors (13.0% vs 12.2%, p<0.001). After accounting for confounders, the highest MPP-CV in decile (CV > 19.2%) were associated with increased risk of hospital mortality compared with those in the fifth and sixth decile (adjusted OR: 1.38, 95% Cl: 1.07-1.78). These relationships remained remarkable in the multiple sensitivity analyses. The validation test with 4,153 individuals also confirmed the results when MPP-CV > 21.3% (adjusted OR: 1.46, 95% Cl: 1.05-2.03).

CONCLUSIONS

Severe fluctuation in MPP was associated with increased short-term mortality in critically ill patients with CVP monitoring.

Higher versus lower blood pressure targets after cardiac arrest: systematic review with individual patient data meta-analysis

PURPOSE

Guidelines recommend targeting mean arterial pressure (MAP) > 65 mmHg in patients after cardiac arrest (CA). Recent trials have studied the effects of targeting a higher MAP as compared to a lower MAP after CA. We performed a systematic review and individual patient data meta-analysis to investigate the effects of higher versus lower MAP targets on patient outcome.

METHOD

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, LILACS, BIOSIS, CINAHL, Scopus, the Web of Science Core Collection, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry, Google Scholar and the Turning Research into Practice database to identify trials randomizing patients to higher (≥ 71 mmHg) or lower (≤70 mmHg) MAP targets after CA and resuscitation. We used the Cochrane Risk of Bias tool, version 2 (RoB 2) to assess for risk of bias. The primary outcomes were 180-day all-cause mortality and poor neurologic recovery defined by a modified Rankin score of 4-6 or a cerebral performance category score of 3-5.

RESULTS

Four eligible clinical trials were identified, randomizing a total of 1,087 patients. All the included trials were assessed as having a low risk for bias. The risk ratio (RR) with 95% confidence interval for 180-day all-cause mortality for a higher versus a lower MAP target was 1.08 (0.92-1.26) and for poor neurologic recovery 1.01 (0.86-1.19). Trial sequential analysis showed that a 25% or higher treatment effect, i.e., RR<0.75, can be excluded. No difference in serious adverse events was found between the higher and lower MAP groups.

CONCLUSIONS

Targeting a higher MAP compared to a lower MAP is unlikely to reduce mortality or improve neurologic recovery after CA. Only a large treatment effect above 25% (RR<0.75) could be excluded, and future studies are needed to investigate if relevant but lower treatment effect exists. Targeting a higher MAP was not associated with any increase in adverse effects.

Volume Management with Kidney Replacement Therapy in the Critically Ill Patient

While the administration of intravenous fluids remains an important treatment, the negative consequences of subsequent fluid overload have raised questions about when and how clinicians should pursue avenues of fluid removal. Decisions regarding fluid removal during critical illness are complex even for patients with preserved kidney function. This article seeks to apply general concepts of fluid management to the care of patients who also require KRT. Because optimal fluid management for any specific patient is likely to change over the course of critical illness, conceptual models using phases of care have been developed. In this review, we will examine the implications of one such model on the use of ultrafiltration during KRT for volume removal in distributive shock. This will also provide a useful lens to re-examine published data of KRT during critical illness. We will highlight recent prospective trials of KRT as well as recent retrospective studies examining ultrafiltration rate and mortality, review the results, and discuss applications and shortcomings of these studies. We also emphasize that current data and techniques suggest that optimal guidelines will not consist of recommendations for or against absolute fluid removal rates but will instead require the development of dynamic protocols involving frequent cycles of reassessment and adjustment of net fluid removal goals. If optimal fluid management is dynamic, then frequent assessment of fluid responsiveness, fluid toxicity, and tolerance of fluid removal will be needed. Innovations in our ability to assess these parameters may improve our management of ultrafiltration in the future.

Fluid balance control in critically ill patients: results from POINCARE-2 stepped wedge cluster-randomized trial

BACKGROUND

In critically ill patients, positive fluid balance is associated with excessive mortality. The POINCARE-2 trial aimed to assess the effectiveness of a fluid balance control strategy on mortality in critically ill patients.

METHODS

POINCARE-2 was a stepped wedge cluster open-label randomized controlled trial. We recruited critically ill patients in twelve volunteering intensive care units from nine French hospitals. Eligible patients were ≥ 18 years old, under mechanical ventilation, admitted to one of the 12 recruiting units for > 48 and ≤ 72 h, and had an expected length of stay after inclusion > 24 h. Recruitment started on May 2016 and ended on May 2019. Of 10,272 patients screened, 1361 met the inclusion criteria and 1353 completed follow-up. The POINCARE-2 strategy consisted of a daily weight-driven restriction of fluid intake, diuretics administration, and ultrafiltration in case of renal replacement therapy between Day 2 and Day 14 after admission. The primary outcome was 60-day all-cause mortality. We considered intention-to-treat analyses in cluster-randomized analyses (CRA) and in randomized before-and-after analyses (RBAA).

RESULTS

A total of 433 (643) patients in the strategy group and 472 (718) in the control group were included in the CRA (RBAA). In the CRA, mean (SD) age was 63.7 (14.1) versus 65.7 (14.3) years, and mean (SD) weight at admission was 78.5 (20.0) versus 79.4 (23.5) kg. A total of 129 (160) patients died in the strategy (control) group. Sixty-day mortality did not differ between groups [30.5%, 95% confidence interval (CI) 26.2-34.8 vs. 33.9%, 95% CI 29.6-38.2, p = 0.26]. Among safety outcomes, only hypernatremia was more frequent in the strategy group (5.3% vs. 2.3%, p = 0.01). The RBAA led to similar results.

CONCLUSION

The POINCARE-2 conservative strategy did not reduce mortality in critically ill patients. However, due to open-label and stepped wedge design, intention-to-treat analyses might not reflect actual exposure to this strategy, and further analyses might be required before completely discarding it. Trial registration POINCARE-2 trial was registered at ClinicalTrials.gov (NCT02765009). Registered 29 April 2016.

Feasibility and Utility of the Venous Excess Ultrasound Score to Detect and Grade Central Venous Pressure Elevation in Critically Ill Children

OBJECTIVES

The Venous Excess Ultrasound (VExUS) score has been described as a useful tool to estimate the degree of venous congestion in adult patients. The present study aimed to analyze the feasibility and usefulness of the VExUS score to detect and grade central venous pressure (CVP) elevation in critically ill children.

METHODS

A cross-sectional pilot study was conducted in a tertiary-care pediatric intensive care unit between November 2020 and June 2021. All children in whom CVP was monitored, were enrolled. At the time of central venous catheter placement, CVP and VExUS score grade were determined, analyzing the inferior vena cava (IVC) diameter and the hepatic (HVD), portal (PVD), and intrarenal (IRVD) venous Doppler waveforms.

RESULTS

A total of 33 children were studied (median age 12.2 [interquartile range (IQR) 4.1-100.6] months old; median weight 8.5 [IQR 5.6-35] kg; 20 [60.6%] males). The VExUS score was successfully obtained in 100% of the patients and its severity was strongly associated with the CVP levels (P < .001). Analyzing the VExUS score components separately, IVC dilation (P < .001) and severe HVD (P = .026), mild IRVD (P = .005), and severe IRVD (P = .025) patterns were associated with elevated CVP. After adjustment for confounding factors, IRVD pattern remained the only independent variable associated with elevated CVP.

CONCLUSIONS

The VExUS score appears to be a feasible and potentially useful bedside noninvasive monitoring tool for the detection and grading of CVP elevation in critically ill children. Among all its components, IRVD assessment seems most associated with high CVP in this population.

Neonatal fluid overload-ignorance is no longer bliss

Excessive accumulation of fluid may result in interstitial edema and multiorgan dysfunction. Over the past few decades, the detrimental impact of fluid overload has been further defined in adult and pediatric populations. Growing evidence highlights the importance of monitoring, preventing, managing, and treating fluid overload appropriately. Translating this knowledge to neonates is difficult as they have different disease pathophysiologies, and because neonatal physiology changes rapidly postnatally in many of the organ systems (i.e., skin, kidneys, and cardiovascular, pulmonary, and gastrointestinal). Thus, evaluations of the optimal targets for fluid balance need to consider the disease state as well as the gestational and postmenstrual age of the infant. Integration of what is known about neonatal fluid overload with individual alterations in physiology is imperative in clinical management. This comprehensive review will address what is known about the epidemiology and pathophysiology of neonatal fluid overload and highlight the known knowledge gaps. Finally, we provide clinical recommendations for monitoring, prevention, and treatment of fluid overload.

Prognostic value of phase angle and bioelectrical impedance vector in critically ill patients: A systematic review and meta-analysis of observational studies

BACKGROUND AND AIMS

Assessment of the raw parameters derived from bioelectrical impedance analysis (BIA) has gained emphasis in critically ill patients. The phase angle (PhA) reflects the integrity of the cell membrane, and bioelectrical impedance vector analysis (BIVA) is indicative of patients' hydration status. The aim of this study was to investigate whether these parameters are associated with clinical outcomes in the intensive care unit (ICU) setting.

METHODS

We conducted a systematic review with meta-analysis. We searched PubMed, Embase, Scopus and Web of Science for all published observational studies without language restrictions up to April 2022. Two reviewers independently performed study selection and data extraction. We judged the risk of bias by the Newcastle-Ottawa Scale and the certainty of evidence by the GRADE approach. Mortality was the primary outcome. Secondary outcomes included ICU length of stay, hospital length of stay, duration of mechanical ventilation, nutritional risk, and malnutrition. A meta-analysis with a random-effect model was performed to combine data on R version 3.6.2.

RESULTS

Twenty-seven studies were included in the systematic review (4872 participants). Pooled analysis revealed that patients with low PhA had a higher risk of death (14 studies; RR = 1.82, 95% CI 1.46 to 2.26; I² = 42%) and spent more days in ICU (6 studies; MD = 1.79, 95% CI 0.33 to 3.24, I² = 69%) in comparison to patients with normal PhA. The pooled analysis also showed higher PhA values in survivors compared to non-survivor patients (12 studies; MD = 0.75°, 95% CI 0.60° to 0.91°, I² = 31%). Overhydration defined by BIVA was not a predictor of mortality (4 studies; RR = 1.01, 95% CI 0.70 to 1.46; I² = 0%). More than 40% of primary studies were classified with a high risk of bias, and the quality of evidence ranged from low to very low.

CONCLUSIONS

This meta-analysis revealed, with limited evidence, that low PhA was associated with higher mortality and ICU length of stay, while overhydration identified by BIVA was not a predictor of death in critically ill patients.

Perfusion-based deresuscitation during continuous renal replacement therapy: A before-after pilot study (The early dry Cohort)

BACKGROUND

Active fluid removal has been suggested to improve prognosis following the resolution of acute circulatory failure. We have implemented a routine care protocol to guide fluid removal during continuous renal replacement therapy (CRRT). We designed a before-after pilot study to evaluate the impact of this deresuscitation strategy on the fluid balance.

METHODS

Consecutive ICU patients suffering from fluid overload and undergoing CRRT for acute kidney injury underwent a perfusion-based deresuscitation protocol combining a restrictive intake, net ultrafiltration (UFnet) of 2 mL/kg/h, and monitoring of perfusion (early dry group, N = 42) and were compared to a historical group managed according to usual practices (control group, N = 45). The primary outcome was the cumulative fluid balance at day 5 or at discharge.

RESULTS

Adjusted cumulative fluid balance was significantly lower in the early dry group (median [IQR]: -7784 [-11,833 to -2933] mL) compared to the control group (-3492 [-9935 to -1736] mL; p = 0.04). The difference was mainly driven by a greater daily UFnet (31 [22-46] mL/kg/day vs. 24 [15-32] mL/kg/day; p = 0.01). There was no significant difference between both groups regarding hemodynamic tolerance.

CONCLUSION

Our perfusion-based deresuscitation protocol achieved a greater negative cumulative fluid balance compared to standard practices and was hemodynamically well tolerated.

Nordic survey on assessment and treatment of fluid overload in intensive care

Introduction

Fluid overload in patients in the intensive care unit (ICU) is associated with higher mortality. There are few randomized controlled trials to guide physicians in treating patients with fluid overload in the ICU, and no guidelines exist. We aimed to elucidate how ICU physicians from Nordic countries define, assess, and treat fluid overload in the ICU.

Materials and methods

We developed an online questionnaire with 18 questions. The questions were pre-tested and revised by specialists in intensive care medicine. Through a network of national coordinators. The survey was distributed to a wide range of Nordic ICU physicians. The distribution started on January 5th, 2022 and ended on May 6th, 2022.

Results

We received a total of 1,066 responses from Denmark, Norway, Finland, Sweden, and Iceland. When assessing fluid status, respondents applied clinical parameters such as clinical examination findings, cumulative fluid balance, body weight, and urine output more frequently than cardiac/lung ultrasound, radiological appearances, and cardiac output monitoring. A large proportion of the respondents agreed that a 5% increase or more in body weight from baseline supported the diagnosis of fluid overload. The preferred de-resuscitation strategy was diuretics (91%), followed by minimization of maintenance (76%) and resuscitation fluids (71%). The majority declared that despite mild hypotension, mild hypernatremia, and ongoing vasopressor, they would not withhold treatment of fluid overload and would continue diuretics. The respondents were divided when it came to treating fluid overload with loop diuretics in patients receiving noradrenaline. Around 1% would not administer noradrenaline and diuretics simultaneously and 35% did not have a fixed upper limit for the dosage. The remaining respondents 63% reported different upper limits of noradrenaline infusion (0.05-0.50 mcg/kg/min) when administering loop diuretics.

Conclusion

Self-reported practices among Nordic ICU physicians when assessing, diagnosing, and treating fluid overload reveals variability in the practice. A 5% increase in body weight was considered a minimum to support the diagnosis of fluid overload. Clinical examination findings were preferred for assessing, diagnosing and treating fluid overload, and diuretics were the preferred treatment modality.

Fluid overload and mortality in critically ill patients with severe heart failure and cardiogenic shock-An observational cohort study

OBJECTIVE

Patients with heart failure (HF) and cardiogenic shock are especially prone to the negative effects of fluid overload (FO); however, fluid resuscitation in respective patients is sometimes necessary resulting in FO. We aimed to study the association of FO at ICU discharge with 30-day mortality in patients admitted to the ICU due to severe heart failure and/or cardiogenic shock.

METHODS

Retrospective, single-center cohort study. Patients with admission diagnoses of severe HF and/or cardiogenic shock were eligible. The following exclusion criteria were applied: (I) patients younger than 16 years, (II) patients admitted to our intermediate care unit, and (III) patients with incomplete data to determine FO at ICU discharge. We used a cumulative weight-adjusted definition of fluid balance and defined more than 5% as FO. The data were analyzed by univariate and adjusted univariate logistic regression.

RESULTS

We included 2,158 patients in our analysis. 185 patients (8.6%) were fluid overloaded at ICU discharge. The mean FO in the FO group was 7.2% [interquartile range (IQR) 5.8-10%]. In patients with FO at ICU discharge, 30-day mortality was 22.7% compared to 11.7% in non-FO patients (p < 0.001). In adjusted univariate logistic regression, we did not observe any association of FO at discharge with 30-day mortality [odds ratio (OR) 1.48; 95% confidence interval (CI) 0.81-2.71, p = 0.2]. No association between FO and 30-day mortality was found in the subgroups with HF only or cardiogenic shock (all p > 0.05). Baseline lactate (adjusted OR 1.27; 95% CI 1.13-1.42; p < 0.001) and cardiac surgery at admission (adjusted OR 1.94; 95% CI 1.0-3.76; p = 0.05) were the main associated factors with FO at ICU discharge.

CONCLUSION

In patients admitted to the ICU due to severe HF and/or cardiogenic shock, FO at ICU discharge seems not to be associated with 30-day mortality.

Fluid Management, Intra-Abdominal Hypertension and the Abdominal Compartment Syndrome: A Narrative Review

BACKGROUND

General pathophysiological mechanisms regarding associations between fluid administration and intra-abdominal hypertension (IAH) are evident, but specific effects of type, amount, and timing of fluids are less clear.

OBJECTIVES

This review aims to summarize current knowledge on associations between fluid administration and intra-abdominal pressure (IAP) and fluid management in patients at risk of intra-abdominal hypertension and abdominal compartment syndrome (ACS).

METHODS

We performed a structured literature search from 1950 until May 2021 to identify evidence of associations between fluid management and intra-abdominal pressure not limited to any specific study or patient population. Findings were summarized based on the following information: general concepts of fluid management, physiology of fluid movement in patients with intra-abdominal hypertension, and data on associations between fluid administration and IAH.

RESULTS

We identified three randomized controlled trials (RCTs), 38 prospective observational studies, 29 retrospective studies, 18 case reports in adults, two observational studies and 10 case reports in children, and three animal studies that addressed associations between fluid administration and IAH. Associations between fluid resuscitation and IAH were confirmed in most studies. Fluid resuscitation contributes to the development of IAH. However, patients with IAH receive more fluids to manage the effect of IAH on other organ systems, thereby causing a vicious cycle. Timing and approach to de-resuscitation are of utmost importance, but clear indicators to guide this decision-making process are lacking. In selected cases, only surgical decompression of the abdomen can stop deterioration and prevent further morbidity and mortality.

CONCLUSIONS

Current evidence confirms an association between fluid resuscitation and secondary IAH, but optimal fluid management strategies for patients with IAH remain controversial.

Goal-Directed Intraoperative Fluid Therapy Benefits Patients Undergoing Major Gynecologic Oncology Surgery: A Controlled Before-and-After Study

Background

Fluid management during major gynecologic oncology surgeries faces great challenges due to the distinctive characteristics of patients with gynecologic malignancies as well as features of the surgical procedure. Intraoperative goal-directed fluid therapy (GDFT) has been proven to be effective in reducing postoperative complications among major colorectal surgeries; however, the efficacy of GDFT has not been fully studied in gynecologic malignancy surgeries. This study aimed to discuss the influence of GDFT practice in patients undergoing major gynecologic oncology surgery.

Methods

This study was a controlled before-and-after study. From June 2015 to June 2018 in Peking Union Medical College Hospital, a total of 300 patients scheduled for elective laparotomy of gynecological malignancies were enrolled and chronologically allocated into two groups, with the earlier 150 patients in the control group and the latter 150 patients in the GDFT group. The GDFT protocol was applied by Vigileo/FloTrac monitoring of stroke volume and fluid responsiveness to guide intraoperative fluid infusion and the use of vasoactive agents. The primary outcome was postoperative complications within 30 days after surgery. The secondary outcome included length of stay and time of functional recovery.

Results

A total of 249 patients undergoing major gynecologic oncology surgery were analyzed in the study, with 129 in the control group and 120 patients in the GDFT group. Patients in the GDFT group had higher ASA classifications and more baseline comorbidities. GDFT patients received significantly less fluid infusion than the control group (15.8 vs. 17.9 ml/kg/h), while fluid loss was similar (6.9 vs. 7.1 ml/kg/h). GDFT was associated with decreased risk of postoperative complications (OR = 0.572, 95% CI 0.343 to 0.953, P = 0.032), especially surgical site infections (OR = 0.127, 95% CI 0.003 to 0.971, P = 0.037). The postoperative bowel function recovery and length of hospital stay were not significantly different between the two groups.

Conclusion

Goal-directed intraoperative fluid therapy is associated with fewer postoperative complications in patients undergoing major gynecologic oncology surgery.

Expression and 7-day time course of circulating microRNAs in septic patients treated with nephrotoxic antibiotic agents

Background

Through regulation of signaling pathways, microRNAs (miRNAs) can be involved in sepsis and associated organ dysfunction. The aims of this study were to track the 7-day time course of blood miRNAs in patients with sepsis treated with vancomycin, gentamicin, or a non-nephrotoxic antibiotic and miRNA associations with neutrophil gelatinase-associated lipokalin (NGAL), creatinine, procalcitonin, interleukin-6, and acute kidney injury (AKI) stage.

Methods

Of 46 adult patients, 7 were on vancomycin, 20 on gentamicin, and 19 on another antibiotic. Blood samples were collected on days 1, 4, and 7 of treatment, and miRNAs were identified using quantitative reverse transcription PCR.

Results

The results showed no relationship between miRNA levels and biochemical variables on day 1. By day 7 of gentamicin treatment miR-15a-5p provided good discrimination between AKI and non-AKI (area under curve, 0.828). In patients taking vancomycin, miR-155-5p and miR-192-5p positively correlated with creatinine and NGAL values, and miR-192-5p and miR-423-5p positively correlated with procalcitonin and interleukin-6 in patients treated with a non-nephrotoxic antibiotic. In patients together we found positive correlation between miR-155-5p and miR-423-5p and all biochemical markers.

Conclusion

The results suggest that these four miRNAs may serve as diagnostic or therapeutic tool in sepsis, renal injury and nephrotoxic treatment.

Trial registration

ClinicalTrials.gov, ID: NCT04991376. Registered on 27 July 2021.

Novel Methods for Predicting Fluid Responsiveness in Critically Ill Patients—A Narrative Review

In patients with acute circulatory failure, fluid administration represents a first-line therapeutic intervention for improving cardiac output. However, only approximately 50% of patients respond to fluid infusion with a significant increase in cardiac output, defined as fluid responsiveness. Additionally, excessive volume expansion and associated hyperhydration have been shown to increase morbidity and mortality in critically ill patients. Thus, except for cases of obvious hypovolaemia, fluid responsiveness should be routinely tested prior to fluid administration. Static markers of cardiac preload, such as central venous pressure or pulmonary artery wedge pressure, have been shown to be poor predictors of fluid responsiveness despite their widespread use to guide fluid therapy. Dynamic tests including parameters of aortic blood flow or respiratory variability of inferior vena cava diameter provide much higher diagnostic accuracy. Nevertheless, they are also burdened with several significant limitations, reducing the reliability, or even precluding their use in many clinical scenarios. This non-systematic narrative review aims to provide an update on the novel, less employed dynamic tests of fluid responsiveness evaluation in critically ill patients.

Fluid Overload Phenotypes in Critical Illness-A Machine Learning Approach

BACKGROUND

The detrimental impact of fluid overload (FO) on intensive care unit (ICU) morbidity and mortality is well known. However, research to identify subgroups of patients particularly prone to fluid overload is scarce. The aim of this cohort study was to derive "FO phenotypes" in the critically ill by using machine learning techniques.

METHODS

Retrospective single center study including adult intensive care patients with a length of stay of ≥3 days and sufficient data to compute FO. Data was analyzed by multivariable logistic regression, fast and frugal trees (FFT), classification decision trees (DT), and a random forest (RF) model.

RESULTS

Out of 1772 included patients, 387 (21.8%) met the FO definition. The random forest model had the highest area under the curve (AUC) (0.84, 95% CI 0.79-0.86), followed by multivariable logistic regression (0.81, 95% CI 0.77-0.86), FFT (0.75, 95% CI 0.69-0.79) and DT (0.73, 95% CI 0.68-0.78) to predict FO. The most important predictors identified in all models were lactate and bicarbonate at admission and postsurgical ICU admission. Sepsis/septic shock was identified as a risk factor in the MV and RF analysis.

CONCLUSION

The FO phenotypes consist of patients admitted after surgery or with sepsis/septic shock with high lactate and low bicarbonate.

Fluid overload in children with pediatric acute respiratory distress syndrome: A retrospective cohort study

OBJECTIVES

To assess the association of cumulative fluid overload (FO) up to 14 days from the diagnosis of pediatric acute respiratory syndrome (PARDS) with pediatric intensive care unit (PICU) mortality, 28-day mechanical ventilation free days (VFD), and 28-day intensive care unit free days (IFD). We hypothesized that fluid overload, even beyond the acute period, would be associated with increased morbidity and mortality.

METHODS

We conducted a retrospective cohort study of PARDS patients admitted to PICU from 2009 to 2015. For repeated admissions, we considered the admission with the highest oxygenation index (OI). Daily FO (%) was calculated as (intake - output)/weight at PICU admission × 100. Peak cumulative FO (CFO) was the highest CFO from the diagnosis of PARDS to Day 14 or to PICU discharge or mortality, whichever was earliest. Rate to peak CFO was the peak CFO divided by the number of days to reach that highest CFO. The association of FO with mortality, VFD and IFD were analyzed with logistic and linear regression models, with the following covariates: Pediatric Index of Mortality 2 score, PARDS severity, and the presence of acute kidney injury (AKI).

RESULTS

There were 165 patients included in this study, with a mortality rate of 45.5% (75/165), median age 3.2 years (interquartile range [IQR] 0.7-9.9) and OI 15.8 (IQR 9.5-27.9). Seventy-three (44.2%) patients had severe PARDS and 64 (38.8%) had AKI. AKI (aOR [adjusted odds ratio] 3.19, 95% CI [confidence interval] 1.43-7.09, p = 0.004) and rate to peak cumulative FO (aOR 1.23, 95% CI 1.07-1.42, p = 0.004) were associated with mortality. AKI and peak cumulative FO were associated with decreased VFD and IFD.

CONCLUSION

The rate to peak CFO over the first 14 days of PARDS was associated with mortality and peak CFO was associated with decreased VFD and IFD.

Ten answers to key questions for fluid management in intensive care

This review focuses on fluid management of critically ill patients. The topic is addressed based on 10 single questions with simplified answers that provide clinicians with the basic information needed at the point of care in treating patients in the Intensive Care Unit. The review has didactic purposes and may serve both as an update on fluid management and as an introduction to the subject for novices in critical care. There is an urgent need to increase awareness regarding the potential risks associated with fluid overload. Clinicians should be mindful not only of the indications for administering fluid loads and of the type of fluids administered, but also of the importance to set safety limits. Lastly, it is important to implement proactive strategies seeking to establish negative fluid balance as soon as the clinical conditions are considered to be stable and the risk of deterioration is low.

Ultrasound Hepatic Vein Ratios Are Associated With the Development of Acute Kidney Injury After Cardiac Surgery

OBJECTIVE

The authors investigated the use of hepatic venous and right-heart ultrasound parameters in predicting cardiac surgery-associated acute kidney injury (AKI).

DESIGN

This was a prospective, contextual, descriptive two-center study. Blood tests,clinical and ultrasound data were obtained preoperatively, and postoperative day one, and day four. The hepatic vein, inferior vena cava, and right-heart Doppler ultrasound parameters were obtained and analyzed.

SETTING

The sites of the study were Johannesburg, South Africa, and Aarhus, Denmark.

PARTICIPANTS

Adult patients who satisfied inclusion criteria, between August 2019 and January 2020, were included, with a total of 152 participants.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The median (interquartile range) age of patients was 68 (55-73) years, predominantly male, and the majority were hypertensive. Of 152 patients analyzed, 54 (35%) patients developed AKI. Among these, 37 (69%) were classified as Kidney Disease: Improving Global Outcomes (KDIGO) stage I, 11 (20%) as stage II, while six (11%) were stage III. Age (adjusted odds ratio [AOR] 1.05, 95% confidence interval [CI] 1.00-1.10 p = 0.031), The European System for Cardiac Operative Risk Evaluation (EuroSCORE) II (AOR 1.43, 95% CI 1.14-1.80, p = 0.005], and preoperative serum creatinine (AOR 1.04, 95% CI 1.01-1.08, p = 0.013) were predictive of AKI. Those who developed AKI had experienced longer cardiopulmonary bypass (CPB) times (p < 0.001). Preoperatively, hepatic vein S-wave measurements were significantly higher in patients with AKI (p < 0.05). On postoperative day one (D1), the hepatic vein flow ratios of patients with AKI were significantly decreased, driven by low S waves and high D waves, and accompanied by significantly elevated central venous pressure (CVP) levels. CVP levels on D1 postoperatively were predictive of AKI (AOR 1.31, 95% CI 1.11-1.55, p = 0.001). Measurements of right ventricular (RV) base, tricuspid annular plane excursion (TAPSE), and inferior vena cava were not associated with the development of AKI (p > 0.05).

CONCLUSION

There was an association between the development of AKI and a decrease in hepatic flow ratios on D1, driven by low S-wave and high D-wave velocities. The presence of venous congestion was reflected by significantly elevated CVP values, which were independently associated with AKI on D1. RV base and TAPSE measurements were, however, not associated with AKI. These parameters may reflect perioperative circumstances, including prolonged CPB times and potential fluid management, which can be modified in this period.

Fluid Accumulation in Critically Ill Children

OBJECTIVES

To describe the characteristics of fluid accumulation in critically ill children and evaluate the association between the degree, timing, duration, and rate of fluid accumulation and patient outcomes.

DESIGN

Retrospective cohort study.

SETTING

PICUs in Alberta, Canada.

PATIENTS

All children admitted to PICU in Alberta, Canada, between January 1, 2015, and December 31, 2015.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 1,017 patients were included. Fluid overload % increased from median (interquartile range) 1.58% (0.23-3.56%; n = 1,017) on day 1 to 16.42% (7.53-27.34%; n = 111) on day 10 among those remaining in PICU. The proportion of patients (95% CI) with peak fluid overload % greater than 10% and greater than 20% was 32.7% (29.8-35.7%) and 9.1% (7.4-11.1%), respectively. Thirty-two children died (3.1%) in PICU. Peak fluid overload % was associated with greater PICU mortality (odds ratio, 1.05; 95% CI, 1.02-1.09; p = 0.001). Greater peak fluid overload % was associated with Major Adverse Kidney Events within 30 days (odds ratio, 1.05; 95% CI, 1.02-1.08; p = 0.001), length of mechanical ventilation (B coefficient, 0.66; 95% CI, 0.54-0.77; p < 0.001), and length of PICU stay (B coefficient, 0.52; 95% CI, 0.46-0.58; p < 0.001). The rate of fluid accumulation was associated with PICU mortality (odds ratio, 1.15; 95% CI, 1.01-1.31; p = 0.04), Major Adverse Kidney Events within 30 days (odds ratio, 1.16; 95% CI, 1.03-1.30; p = 0.02), length of mechanical ventilation (B coefficient, 0.80; 95% CI, 0.24-1.36; p = 0.005), and length of PICU stay (B coefficient, 0.38; 95% CI, 0.11-0.66; p = 0.007).

CONCLUSIONS

Fluid accumulation occurs commonly during PICU course and is associated with considerable mortality and morbidity. These findings highlight the need for the development and evaluation of interventional strategies to mitigate the potential harm associated with fluid accumulation.

Admission factors associated with nutritional status deterioration and prolonged pediatric intensive care unit stay in critically ill children: PICU-ScREEN multicenter study

BACKGROUND

Early identification of patients in the pediatric intensive care unit (PICU) at risk of nutritional status (NS) deterioration and poor outcomes is desirable. We aimed to identify factors associated with NS deterioration and prolonged PICU stay.

METHODS

Prospective cohort study in eight Brazilian PICUs with children <18 years with a PICU stay >72h. We used multivariable logistic regression to identify the clinical, laboratory, and nutrition variables at admission that were associated with outcomes. NS deterioration was defined as the reduction in weight-for-age, body mass index-for-age or mid-upper arm circumference-for-age z-score ≥1 during PICU stay. Prolonged PICU stay was defined as ≥13 days.

RESULTS

We enrolled 363 eligible patients, median age 11.3 months (interquartile range:3.1-45.6) and 46% had at least one complex chronic condition (CCC). NS deterioration was observed in 23% of participants and was associated with CCC (odds ratio [OR]:2.71; 95% confidence interval [CI]:1.44-5.09), after adjusting for severity risk score, leukocyte count, obesity, and PICU site. Prolonged PICU stay was associated with age <2 years (OR:1.95; 95%CI:1.03-3.66), fluid overload (>10%) over the first 72h (OR:2.66; 95%CI:1.50-4.73), and hypoalbuminemia (<3.0 g/dL) (OR:2.05; 95%CI:1.12-3.76), after adjusting for CCC, severity risk score, undernutrition, early nutrition therapy, and PICU site.

CONCLUSIONS

CCC at admission was associated with NS deterioration. Age <2 years, fluid overload, and hypoalbuminemia at PICU admission were associated with prolonged PICU stay. These factors must be further evaluated as part of an admission nutrition screening tool for critically ill children.

Kidney Replacement Therapy for Fluid Management

Emerging evidence from observational studies suggests that both slower and faster net ultrafiltration rates during kidney replacement therapy are associated with increased mortality in critically ill patients with acute kidney injury and fluid overload. Faster rates are associated with ischemic organ injury. The net ultrafiltration rate should be prescribed based on patient body weight in milliliters per kilogram per hour, with close monitoring of patient hemodynamics and fluid balance. Randomized trials are required to examine whether moderate net ultrafiltration rates compared with slower and faster rates are associated with reduced risk of hemodynamic instability, organ injury, and improved outcomes.

Fluid balance management during continuous renal replacement therapy

In critically ill patients, particularly in the setting of shock and sepsis volume management frequently results in a fluid overloaded state, requiring diuresis or intervention with renal replacement therapy. Achieving appropriate volume management requires knowledge of the underlying cardiovascular pathophysiology and careful evaluation of intravascular and extravascular volume status. In the presence of a failing kidney, fluid removal is often a challenge. Continuous renal replacement therapy (CRRT) techniques offer a significant advantage over intermittent dialysis for fluid control, however, any form of RRT in the critically ill patient requires careful attention to prescription and monitoring to avoid complications. In order to utilize these therapies for their maximum potential it is necessary to understand which factors influence fluid balance and have an understanding of the principles and kinetics of fluid removal with extra-corporeal techniques.

Targeted high volume hemofiltration could avoid extracorporeal membrane oxygenation in some patients with severe Hantavirus cardiopulmonary syndrome

Background

Hantavirus cardiopulmonary syndrome (HCPS) has a high lethality. Severe cases may be rescued by venoarterial extracorporeal membrane oxygenation (VA ECMO), alongside substantial complications. High volume hemofiltration (HVHF) is a depurative technique that provides homeostatic balance allowing hemodynamic stabilization in some critically ill patients.

Methods

We implemented HVHF before VA ECMO consideration in the last five severe HCPS patients requiring mechanical ventilation and vasoactive drugs admitted to our intensive care unit. Patients were considered HVHF‐responders if VA ECMO was avoided and HVHF‐nonresponders if VA ECMO support was needed despite HVHF. A targeted‐HVHF strategy compounded by aggressive hyperoncotic albumin, sodium bicarbonate, and calcium supplementation plus ultrafiltration to avoid fluid overload was implemented on three patients.

Results

Patients had maximum serum lactate of 8.8 (8.7–12.8) mmol/L and a lowest cardiac index of 1.8 (1.8–1.9) L/min/m². The first two required VA ECMO. They were connected later to HVHF, displayed progressive tachycardia and declining stroke volume. The opposite was true for HVHF‐responders who received targeted‐HVHF. All patients survived, but one of the VA ECMO patients suffered a vascular complication.

Conclusion

HVHF may contribute to support severe HCPS patients avoiding the need for VA ECMO in some. Early connection and targeted‐HVHF may increase the chance of success.

Inferior vena cava dilation predicts global cardiac dysfunction in acute respiratory distress syndrome: A strain echocardiographic study

PURPOSE

Limited data exist on the utility of ultrasonographic evaluation of inferior vena cava (IVC) in acute respiratory distress syndrome (ARDS). We studied the value of IVC diameter in assessing cardio-circulatory performance in ARDS using strain echocardiography.

MATERIALS AND METHODS

Retrospective cross-sectional analysis of Doppler echocardiograms of patients with moderate-severe ARDS was performed. Right ventricle (RV) parameters, IVC diameter, and left ventricle (LV) systolic and diastolic parameters were collected. RV free wall strain (RVFWS) and LV global longitudinal strain (LVGLS) were calculated.

RESULTS

Fifty-one patients were dichotomized into two groups: with IVC > 2.1 cm (dilated) and with IVC ≤ 2.1 cm (nondilated). The dilated IVC group presented worse hypoxemic profile, hypotension, and poor perfusion markers. No significant associations with positive end-expiratory pressure or lung mechanics were observed. Dilated IVC was associated with impaired RV function, high central venous pressure, elevated pulmonary artery pressure, and LV systolic and diastolic dysfunctions. Strongest predictors of a dilated IVC were RVFWS, LVGLS, and tissue Doppler mitral annular early diastolic velocity. Dilated IVC predicted a global cardiac dysfunction defined by strain echocardiography (GCDS) with high sensitivity and specificity.

CONCLUSIONS

In ARDS, strain echocardiography analyses demonstrated that a dilated IVC is associated with GCDS and impaired hemodynamics independent of lung mechanics. A dilated IVC should be considered a marker of circulatory distress, signaling the potential necessity for improved hemodynamic optimization.

Intra-abdominal hypertension, fluid balance, and adverse outcomes after orthotopic liver transplantation

BACKGROUND

Intra-abdominal hypertension (IAH) is frequently encountered in critically ill surgical patients. We aimed to evaluate the incidence of IAH after orthotopic liver transplant (OLT) and its impact on organ function, hospital length-of-stay (LOS), and death.

METHODS

This prospective, observational, cohort study evaluated consecutive adult patients admitted in the ICU after undergoing OLT. Intra-abdominal pressure (IAP) was measured every 4-6 h for 3 days. Worsening IAP was defined as a gradual increase in IAP over a period of time. Daily fluid balance was the daily sum of all intakes minus the output.

RESULTS

IAH was observed in 48% of the patients within the first 3 days after ICU admission, while ACS was diagnosed in 15%. Patients with IAH had a higher positive fluid balance at day 1 (1764 mL [812-2733 mL] vs. 1301 mL [241-1904 mL], p = 0.025). Worsening IAH was associated with fewer days free of organ dysfunction. IAH within 72 h after ICU admission was independently associated with a composite outcome of death or a longer ICU LOS (odds ratio 2.9; CI 95% 1.02-8.25, p = 0.043).

CONCLUSION

After OLT, nearly half of the patients presented IAH, that was associated with unfavorable outcomes.

Ten answers to key questions for fluid management in intensive care

This review focuses on fluid management of critically ill patients. The topic is addressed based on 10 single questions with simplified answers that provide clinicians with the basic information needed at the point of care in treating patients in the Intensive Care Unit. The review has didactic purposes and may serve both as an update on fluid management and as an introduction to the subject for novices in critical care. There is an urgent need to increase awareness regarding the potential risks associated with fluid overload. Clinicians should be mindful not only of the indications for administering fluid loads and of the type of fluids administered, but also of the importance to set safety limits. Lastly, it is important to implement proactive strategies seeking to establish negative fluid balance as soon as the clinical conditions are considered to be stable and the risk of deterioration is low.