Cumulative positive fluid balance is a risk factor for acute kidney injury and requirement for renal replacement therapy after liver transplantation

Postoperative fluid balance and outcomes in pediatric living-donor liver transplant recipients: a retrospective cohort study

PURPOSE

This study aimed to investigate the relationship between postoperative fluid balance (FB) and clinical outcomes in pediatric living-donor liver transplant (LDLT) recipients.

METHODS

This retrospective study was conducted at a tertiary care center. Patients aged ≤ 18 years who underwent LDLT between January 2010 and September 2023 were included. Postoperative FB was calculated as [(total fluid intake-total fluid output) / body weight] × 100 for 48 h. Patients were categorized into four groups: < 5%, 5-10%, 10-15%, and ≥ 15% FB. The primary outcome was ventilator-free days (VFD) within 30 days post-transplantation. Secondary outcomes included acute kidney injury (AKI), reintubation, hepatic arterial thrombosis, acute rejection, primary graft dysfunction, intensive care unit (ICU) length of stay (LOS), and mortality.

RESULTS

The study included 200 patients with a median weight of 9.0 (interquartile range [IQR]: 6.9-19.3) kg. Median VFD did not significantly differ across the FB groups: < 5% FB, 29.3 (IQR, 28.3-29.4) days; 5-10% FB, 29.3 (IQR, 28.3-29.4) days; 10-15% FB, 29.3 (IQR, 28.3-29.4) days; and ≥ 15% FB, 27.4 (IQR, 23.3-29.4) days (p = 0.27). However, multivariable analysis showed ≥ 15% FB was associated with 4.59 days shorter VFD (p = 0.004) and higher AKI incidence (odds ratio: 6.60, p = 0.012). Thrombosis occurred in 7 patients (3.5%) with no significant differences among groups (p = 0.61). Other secondary outcomes showed no significant differences.

CONCLUSION

Excessive postoperative FB (≥ 15%) in pediatric LDLT recipients was significantly associated with reduced VFD and increased AKI incidence, whereas other adverse outcomes were not significantly affected.

Fluid balance dynamics and early postoperative outcomes in orthotopic liver transplantation: a prospective cohort study

INTRODUCTION

This study evaluates the impact of Fluid Balance (FB) patterns on outcomes after Orthotopic Liver Transplantation (OLT). It hypothesizes that deviations from optimal FB increase morbidity.

METHODS

In a single-center cohort post hoc analysis of 73 post-OLT patients, FB was categorized into three groups based on cumulative FB at 72 hours: Lowest (negative FB), Intermediate (0-2000 mL), and Highest (> 2000 mL). We analyzed Sequential Organ Failure Assessment (SOFA) scores, mortality rates, and causes of death. Logistic regression identified mortality predictors.

RESULTS

The Highest FB group had the highest SOFA scores and mortality (Group "Lo": 18.2%, Group "In": 8.6%, Group "Hi": 40.5%, p = 0.009). A U-shaped relationship between FB and hospital mortality was observed, with extremes of FB associated with higher mortality. Cumulative FB independently predicted all-cause mortality with a 29.5% increase in the risk of death. FB on day 3 also predicted all-cause mortality, increasing the risk by 83.9%. Furthermore, FB on day 1 was linked to a 134.5% increase in the risk of death due to primary non-function of the liver. SOFALIVER score strongly predicted all-cause mortality, with a one-point increase associated with a 98.8% to 114.7% increase in mortality risk.

DISCUSSION

These findings suggest that both negative and positive extremes of FB are associated with worse outcomes after OLT, reinforcing the U-shaped relationship between FB and mortality. Our results underscore the importance of balanced fluid management, particularly in the early postoperative period. The study highlights the need for individualized FB strategies to optimize organ function and reduce mortality. The use of SOFALIVER scores as a predictor of mortality further emphasizes the importance of liver function monitoring in post-OLT patients. However, the single-centre design and convenience sample limit the generalizability of our findings, necessitating validation through multicenter studies.

CONCLUSION

Our study provides valuable insights into the relationship between FB patterns and mortality in OLT patients. Both negative and positive extremes of FB are associated with higher mortality, suggesting the need for a balanced and individualized fluid management approach. The strong predictive value of SOFALIVER scores for all-cause mortality highlights the importance of early and continuous monitoring of liver function. Future multicenter randomized controlled trials are needed to validate these findings and develop optimized fluid management protocols for OLT patients.

Latin American association for the study of the liver (ALEH) guidance on postoperative care after liver transplantation

Liver transplantation (LT) is a well-established therapy for patients with decompensated cirrhosis and early-stage hepatocellular carcinoma. Liver transplantation activity varies sharply across Latin American (LATAM) countries due to differences in resources, expertise, and funding and local attitudes toward organ donation and transplantation. This current guidance of postoperative care after LT is the first position paper of the Latin American Association for the Study of the Liver (ALEH) Special Interest Group (SIG), drawing evidence-based recommendations regarding immediate and long-term postoperative care of LT recipients, taking into consideration their applicability in Latin America.

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.

Risk factors and prediction score for new-onset diabetes mellitus after liver transplantation

AIM

New-onset diabetes mellitus is a frequent and severe complication arising after liver transplantation (LT). We aimed to identify the risk factors for new-onset diabetes mellitus after liver transplantation (NODALT) and to develop a risk prediction score system for relevant risks.

METHODS

We collected and analyzed data from all recipients who underwent liver transplantation at the First Affiliated Hospital of Xi'an Jiaotong University. The OR derived from a multiple logistic regression predicting the presence of NODALT was used to calculate the risk prediction score. The performance of the risk prediction score was externally validated in patients who were from the CLTR (China Liver Transplant Registry) database.

RESULTS

A total of 468 patients met the outlined criteria and finished the follow-up. Overall, NODALT was diagnosed in 115 (24.6%) patients. Age, preoperative impaired fasting glucose (IFG), postoperative fasting plasma glucose (FPG), and the length of hospital stay were significantly associated with the presence of NODALT. The risk prediction score includes age, preoperative IFG, postoperative FPG, and the length of hospital stay. The risk prediction score of the area under the receiver operating curve was 0.785 (95% CI: 0.724-0.846) in the experimental population and 0.782 (95% CI: 0.708-0.856) in the validation population.

CONCLUSIONS

Age at the time of transplantation, preoperative IFG, postoperative FPG, and length of hospital stay were independent predictive factors of NODALT. The use of a simple risk prediction score can identify the patients who have the highest risk of NODALT and interventions may start early.

Objective Methods of Assessing Fluid Status to Optimize Volume Management in Kidney Disease and Hypertension: The Importance of Ultrasound

Fluid overload, a prevalent complication in patients with renal disease and hypertension, significantly impacts patient morbidity and mortality. The daily clinical challenges that clinicians face include how to identify fluid overload early enough in the course of the disease to prevent adverse outcomes and to guide and potentially reduce the intensity of the diuresis. Traditional methods for evaluating fluid status, such as pitting edema, pulmonary crackles, or chest radiography primarily assess extracellular fluid and do not accurately reflect intravascular volume status or venous congestion. This review explores the rationale, mechanism, and evidence behind more recent methods used to assess volume status, namely, lung ultrasound, inferior vena cava (IVC) ultrasound, venous excess ultrasound score, and basic and advanced cardiac echocardiographic techniques. These methods offer a more accurate and objective assessment of fluid status, providing real-time, non-invasive measures of intravascular volume and venous congestion. The methods we discuss are primarily used in inpatient settings, but, given the increased pervasiveness of ultrasound technology, some could soon expand to the outpatient setting.

A system theory based digital model for predicting the cumulative fluid balance course in intensive care patients

Background: Surgical interventions can cause severe fluid imbalances in patients undergoing cardiac surgery, affecting length of hospital stay and survival. Therefore, appropriate management of daily fluid goals is a key element of postoperative intensive care in these patients. Because fluid balance is influenced by a complex interplay of patient-, surgery- and intensive care unit (ICU)-specific factors, fluid prediction is difficult and often inaccurate. Methods: A novel system theory based digital model for cumulative fluid balance (CFB) prediction is presented using recorded patient fluid data as the sole parameter source by applying the concept of a transfer function. Using a retrospective dataset of n = 618 cardiac intensive care patients, patient-individual models were created and evaluated. RMSE analyses and error calculations were performed for reasonable combinations of model estimation periods and clinically relevant prediction horizons for CFB. Results: Our models have shown that a clinically relevant time horizon for CFB prediction with the combination of 48 h estimation time and 8-16 h prediction time achieves high accuracy. With an 8-h prediction time, nearly 50% of CFB predictions are within ±0.5 L, and 77% are still within the clinically acceptable range of ±1.0 L. Conclusion: Our study has provided a promising proof of principle and may form the basis for further efforts in the development of computational models for fluid prediction that do not require large datasets for training and validation, as is the case with machine learning or AI-based models. The adaptive transfer function approach allows estimation of CFB course on a dynamically changing patient fluid balance system by simulating the response to the current fluid management regime, providing a useful digital tool for clinicians in daily intensive care.

Risk factors for acute kidney injury after liver transplantation in intensive care unit: a retrospective cohort study

BACKGROUND

Acute kidney injury (AKI) is a frequent complication during the postoperative period following liver transplantation. Occurrence of AKI in intensive care unit (ICU) patients is associated with increased mortality and higher costs.

OBJECTIVE

To evaluate occurrences of moderate or severe AKI among patients admitted to the ICU after liver transplantation and investigate characteristics associated with this complication.

DESIGN AND SETTING

Single-center retrospective cohort study in a public hospital, Belo Horizonte, Brazil.

METHODS

Forty-nine patients admitted to the ICU between January 2015 and April 2017 were included. AKI was defined from a modified Kidney Disease Improving Global Outcomes (KDIGO) score (i.e. based exclusively on serum creatinine levels).

RESULTS

Eighteen patients (36.7%) developed AKI KDIGO 2 or 3; mostly KDIGO 3 (16 out of the 18 patients). Lactate level within the first six hours after ICU admission (odds ratio, OR: 1.3; 95% confidence interval, CI: 1.021-1.717; P = 0.034) and blood transfusion requirement within the first week following transplantation (OR: 8.4; 95% CI: 1.687-41.824; P = 0.009) were independently associated with development of AKI. Patients with AKI KDIGO 2 or 3 underwent more renal replacement therapy (72.2% versus 3.2%; P < 0.01), had longer hospital stay (20 days versus 15 days; P = 0.001), higher in-hospital mortality (44.4% versus 6.5%; P < 0.01) and higher mortality rate after one year (44.4% versus 9.7%; P = 0.01).

CONCLUSION

Need for blood transfusion during ICU stay and hyperlactatemia within the first six postoperative hours after liver transplantation are independently associated with moderate or severe AKI. Developing AKI is apparently associated with poor outcomes.

Effect of post-operative goal-directed fluid therapy (GDFT) on organ function after orthotopic liver transplantation: Secondary outcome analysis of the COLT randomised control trial

BACKGROUND

Goal-directed fluid therapy (GDFT) has been shown to reduce the complications following a variety of major surgical procedures, possibly mediated by improved organ perfusion and function. We have shown that it is feasible to randomise patients to GDFT or standard fluid management following liver transplant in the cardiac-output optimisation following liver transplantation (COLT) trial. The current study compares end organ function in patients from the COLT trial who received GDFT in comparison to those receiving standard care (SC) following liver transplant.

METHODS

Adult patients with liver cirrhosis undergoing liver transplantation were randomised to GDFT or SC for the first 12 h following surgery as detailed in a published trial protocol. GDFT protocol was based on stroke volume (SV) optimisation using 250 ml crystalloid boluses. Total fluid administration and time to extubation were recorded. Hourly SV and cardiac output (CO) readings were recorded from the non-invasive cardiac output monitoring (NICOM) device in both groups. Pulmonary function was assessed by arterial blood gas (ABG) and ventilatory parameters. Lung injury was assessed using PaO₂:FiO₂ ratios and calculated pulmonary compliance. The KDIGO score was used for determining acute kidney injury. Renal and liver graft function were assessed during the post-operative period and at 3 months and 1-year.

RESULTS

60 patients were randomised to GDFT (n = 30) or SC (n = 30). All patients completed the 12 h intervention period. GDFT group received a significantly higher total volume of fluid during the 12 h trial intervention period (GDFT 5317 (2335) vs. SC 3807 (1345) ml, p = 0.003); in particular crystalloids (GDFT 3968 (2073) vs. SC 2510 (1027) ml, p = 0.002). There was no evidence of significant difference between the groups in SV or CO during the assessment periods. Time to extubation, PaO2: FIO₂ ratios, pulmonary compliance, ventilatory or blood gas measurements were similar in both groups. There was a significant rise in serum creatinine from baseline (77 μmol/L) compared to first (87 μmol/L, p = 0.039) and second (107 μmol/L, p = 0.001) post-operative days. There was no difference between GDFT and SC in the highest KDIGO scores for the first 7 days post-LT. At 1-year follow-up, there was no difference in need for renal replacement therapy or graft function.

CONCLUSIONS

In this randomised trial of fluid therapy post liver transplant, GDFT was associated with an increased volume of crystalloids administered but did not alter early post-operative pulmonary or renal function when compared with standard care.

Association between Latent Trajectories of Fluid Balance and Clinical Outcomes in Critically Ill Patients with Acute Kidney Injury: A Prospective Multicenter Observational Study

INTRODUCTION

We aimed to identify different trajectories of fluid balance (FB) and investigate the effect of FB trajectories on clinical outcomes in intensive care unit (ICU) patients with acute kidney injury (AKI) and the dose-response association between fluid overload (FO) and mortality.

METHODS

We derived data from the Beijing Acute Kidney Injury Trial (BAKIT). A total of 1,529 critically ill patients with AKI were included. The primary outcome was 28-day mortality, and hospital mortality, ICU mortality and AKI stage were the secondary outcomes. A group-based trajectory model was used to identify the trajectory of FB during the first 7 days. Multivariable logistic regression was performed to examine the relationship between FB trajectories and clinical outcomes. A logistic regression model with restricted cubic splines was used to examine the dose relationship between FO and 28-day mortality.

RESULTS

Three distinct trajectories of FB were identified: low FB (1,316, 86.1%), decreasing FB (120, 7.8%), and high FB (93, 6.1%). Compared with low FB, high FB was associated with increased 28-day mortality (odds ratio [OR] 1.94, 95% confidence interval [CI] 1.17-3.19) and AKI stage (OR 2.04, 95% CI 1.23-3.37), whereas decreasing FB was associated with a reduction in 28-day mortality by approximately half (OR 0.53, 95% CI 0.32-0.87). Similar results were found for the outcomes of ICU mortality and hospital mortality. We observed a J-shaped relationship between maximum FO and 28-day mortality, with the lowest risk at a maximum FO of 2.8% L/kg.

CONCLUSION

Different trajectories of FB in critically ill patients with AKI were associated with clinical outcomes. An FB above or below a certain range was associated with an increased risk of mortality. Further studies should explore this relationship and search for the optimal fluid management strategies for critically ill patients with AKI.

Association of fluid balance trajectories with clinical outcomes in patients with septic shock: a prospective multicenter cohort study

BACKGROUND

Septic shock has a high incidence and mortality rate in Intensive Care Units (ICUs). Earlier intravenous fluid resuscitation can significantly improve outcomes in septic patients but easily leads to fluid overload (FO), which is associated with poor clinical outcomes. A single point value of fluid cannot provide enough fluid information. The aim of this study was to investigate the impact of fluid balance (FB) latent trajectories on clinical outcomes in septic patients.

METHODS

Patients were diagnosed with septic shock during the first 48 h, and sequential fluid data for the first 3 days of ICU admission were included. A group-based trajectory model (GBTM) which is designed to identify groups of individuals following similar developmental trajectories was used to identify latent subgroups of individuals following a similar progression of FB. The primary outcomes were hospital mortality, organ dysfunction, major adverse kidney events (MAKE) and severe respiratory adverse events (SRAE). We used multivariable Cox or logistic regression analysis to assess the association between FB trajectories and clinical outcomes.

RESULTS

Nine hundred eighty-six patients met the inclusion criteria and were assigned to GBTM analysis, and three latent FB trajectories were detected. 64 (6.5%), 841 (85.3%), and 81 (8.2%) patients were identified to have decreased, low, and high FB, respectively. Compared with low FB, high FB was associated with increased hospital mortality [hazard ratio (HR) 1.63, 95% confidence interval (CI) 1.22-2.17], organ dysfunction [odds ratio (OR) 2.18, 95% CI 1.22-3.42], MAKE (OR 1.80, 95% CI 1.04-2.63) and SRAE (OR 2.33, 95% CI 1.46-3.71), and decreasing FB was significantly associated with decreased MAKE (OR 0.46, 95% CI 0.29-0.79) after adjustment for potential covariates.

CONCLUSION

Latent subgroups of septic patients followed a similar FB progression. These latent fluid trajectories were associated with clinical outcomes. The decreasing FB trajectory was associated with a decreased risk of hospital mortality and MAKE.

Effect of positive cumulative fluid balance on postoperative complications after living donor liver transplantation: A retrospective analysis

Background and Aims:

Fluid administration during liver transplant (LT) surgery is controversial. Although adverse outcomes following positive intraoperative fluid balance have been reported, studies presenting the influence of cumulative postoperative fluid balance (CFB) on complications following LT are sparse. Patients with chronic liver disease tend to receive more fluid during and after surgery due to their unique physiological disease state. The aim of this study was to evaluate the influence of 48-hour CFB on the development of acute kidney injury (AKI) and pulmonary complications on day 4 after live donor LT.

Methods:

This retrospective study included 230 patients undergoing live donor LT. The effect of CFB on day 2 on AKI and pulmonary complications was analysed. Chi-square test, Fisher's exact test, samples t-test, Mann-Whitney U-test were used.

Results:

Bivariate analysis showed a lower graft vs recipient weight ratio (GRWR), sepsis (P < 0.001) and a higher 48-hour CFB after surgery significantly increased the development of AKI. For pulmonary complications, higher Model for End- stage Liver Disease-Na(MELD-Na) score, higher peak arterial lactate, higher 48-hour CFB (P = 0.016) and sepsis (P = 0.003) were found to be statistically significant. Upon multivariate analysis, CFB at 48 hours was significantly higher in patients suffering from pulmonary complications, and GRWR and sepsis were significant for AKI. For every one litre increase in CFB on day 2, the odds of pulmonary complications increased by 37%.

Conclusion:

A more positive CFB on day 2 increased the development of pulmonary complications and lower GRWR and sepsis increased the development of AKI.

Modifiable risk factors of acute kidney injury after liver transplantation: a systematic review and meta-analysis

BACKGROUND

Acute kidney injury (AKI) is a common and critical complication of liver transplantation (LT), which is associated with increased morbidity, mortality and health care cost. We aimed to identify modifiable risk factors of AKI after LT.

METHODS

A literature search of Pubmed, EMBASE and Cochrane Databases was performed to identify studies investigating risk factors of AKI after LT. The Newcastle-Ottawa Scale was used to rate study quality. Effect size and 95% confidence interval were pooled using a random-effect model with inverse-variance method.

RESULTS

Sixty-seven articles with 28,844 patients were included in the meta-analysis. Seventeen modifiable risk factors were found, including overweight, preoperative use of diuretic, preoperative anemia, donation after cardiac death organ, donor BMI ≥ 30 kg/m2, ABO-incompatible LT, low graft to recipient body weight ratio, intraoperative hypotension, major bleeding, intraoperative use of vasopressor, large RBC transfusion, postreperfusion syndrome, postoperative use of vasopressors, overexposure to calcineurin inhibitor, calcineurin inhibitor without mycophenolate mofetil, graft dysfunction and infection. A total of 38 articles were included in the systematic review, in which 8 modifiable risk factors and 1 protective factor were additionally associated in single studies with the incidence of AKI after LT.

CONCLUSIONS

Effective interventions based on identified modifiable risk factors in the perioperative management and graft allocation and preservation may be promising to reduce the incidence of AKI after LT.

TRIAL REGISTRATION

The protocol for this systematic review is registered with PROSPERO (No. CRD42020166918 ).

Positive fluid balance as an early biomarker for acute kidney injury: a prospective study in critically ill adult patients

OBJECTIVES

Positive fluid balance is frequent in critically ill patients and has been considered a potential biomarker for acute kidney injury (AKI). This study aimed to evaluate positive fluid balance as a biomarker for the early detection of AKI in critically ill patients.

METHODS

This was a prospective cohort study. The sample was composed of patients ≥18 years old who stayed ≥3 days in an intensive care unit. Fluid balance, urinary output and serum creatinine were assessed daily. AKI was diagnosed by the Kidney Disease Improving Global Outcome criteria.

RESULTS

The final cohort was composed of 233 patients. AKI occurred in 92 patients (40%) after a median of 3 (2-6) days following ICU admission. When fluid balance was assessed as a continuous variable, a 100-ml increase in fluid balance was independently associated with a 4% increase in the odds of AKI (OR 1.04; 95% CI 1.01-1.08). Positive fluid balance categorized using different thresholds was always significantly associated with subsequent detection of AKI. The mixed effects model showed that increased fluid balance preceded AKI by 4 to 6 days.

CONCLUSION

These results suggest that a positive fluid balance might be an early biomarker for AKI development in critically ill patients.

Dose-response association between fluid overload and in-hospital mortality in critically ill patients: a multicentre, prospective, observational cohort study

OBJECTIVES

Fluid management is important in ensuring haemodynamic stability in critically ill patients, but can easily lead to fluid overload (FO). However, the optimal fluid balance plot or range for critically ill patients is unknown. This study aimed to explore the dose-response relationship between FO and in-hospital mortality in critically ill patients.

DESIGN

Multicentre, prospective, observational study.

SETTING

Eighteen intensive care units (ICUs) of 16 tertiary hospitals in China.

PARTICIPANTS

Critically ill patients in the ICU for more than 3 days.

PRIMARY OUTCOME MEASURES AND ANALYSES

FO was defined as the ratio of the cumulative fluid balance (L) and initial body weight (kg) on ICU admission, expressed as a percentage. Maximum FO was defined as the peak value of FO during the first 3 days of ICU admission. Logistic regression models with restricted cubic splines were used to explore the pattern and magnitude of the association between maximum FO and risk of in-hospital mortality. Age, sex, Acute Physiology and Chronic Health Evaluation II score, Sequential Organ Failure Assessment score on admission, main diagnosis on admission to ICU, comorbidities, time of maximum FO, mechanical ventilation, renal replacement therapy, use of vasopressors and centres were adjusted in multivariable analysis.

RESULTS

A total of 3850 patients were included in the study, 929 (24.1%) of whom died in the hospital. For each 1% L/kg increase in maximum FO, the risk of in-hospital mortality increased by 4% (adjusted HR (aHR) 1.04, 95% CI 1.03 to 1.05, p<0.001). A maximum FO greater than 10% was associated with a 44% increased HR of in-hospital mortality compared with an FO less than 5% (aHR 1.44, 95% CI 1.27 to 1.67). Notably, we found a non-linear dose-response association between maximum FO and in-hospital mortality.

CONCLUSIONS

Both higher and negative fluid balance levels were associated with an increased risk of in-hospital mortality in critically ill patients.

TRIAL REGISTRATION NUMBER

ChiCTR-ECH-13003934.

Microcirculation-guided protection strategy in hemodynamic therapy

Microcirculatory shock is a condition defined by the presence of tissue hypoperfusion despite the normalization of systemic and regional blood flow. Currently, more evidence shows that intrinsic septic shock is microcirculatory shock, which results in septic shock that is difficult to resuscitate. At present, treatments are aimed at recovering macro-circulation functions and include fluid resuscitation, vasoactive drugs, positive inotropic drugs, de-obstruction, and even mechanical assistance to improve oxygen delivery. However, the application of these treatments to more accurately improve microcirculation or avoid further microcirculatory damage is more important in clinics. In this article, we discuss the need for microcirculation protection and microcirculation-guided protection strategies in hemodynamic therapies.

Hydroxyethyl starch for perioperative goal-directed fluid therapy in 2020: a narrative review

BACKGROUND

Perioperative fluid management - including the type, dose, and timing of administration -directly affects patient outcome after major surgery. The objective of fluid administration is to optimize intravascular fluid status to maintain adequate tissue perfusion. There is continuing controversy around the perioperative use of crystalloid versus colloid fluids. Unfortunately, the importance of fluid volume, which significantly influences the benefit-to-risk ratio of each chosen solution, has often been overlooked in this debate.

MAIN TEXT

The volume of fluid administered during the perioperative period can influence the incidence and severity of postoperative complications. Regrettably, there is still huge variability in fluid administration practices, both intra-and inter-individual, among clinicians. Goal-directed fluid therapy (GDFT), aimed at optimizing flow-related variables, has been demonstrated to have some clinical benefit and has been recommended by multiple professional societies. However, this approach has failed to achieve widespread adoption. A closed-loop fluid administration system designed to assist anesthesia providers in consistently applying GDFT strategies has recently been developed and tested. Such an approach may change the crystalloid versus colloid debate. Because colloid solutions have a more profound effect on intravascular volume and longer plasma persistence, their use in this more "controlled" context could be associated with a lower fluid balance, and potentially improved patient outcome. Additionally, most studies that have assessed the impact of a GDFT strategy on the outcome of high-risk surgical patients have used hydroxyethyl starch (HES) solutions in their protocols. Some of these studies have demonstrated beneficial effects, while none of them has reported severe complications.

CONCLUSIONS

The type and volume of fluid used for perioperative management need to be individualized according to the patient's hemodynamic status and clinical condition. The amount of fluid given should be guided by well-defined physiologic targets. Compliance with a predefined hemodynamic protocol may be optimized by using a computerized system. The type of fluid should also be individualized, as should any drug therapy, with careful consideration of timing and dose. It is our perspective that HES solutions remain a valid option for fluid therapy in the perioperative context because of their effects on blood volume and their reasonable benefit/risk profile.

The cardiac output optimisation following liver transplant (COLT) trial: a feasibility randomised controlled trial

BACKGROUND

Perioperative goal directed fluid therapy (GDFT) has been shown to reduce postoperative complications following major surgery; this intervention has not been formally evaluated in the setting of liver transplantation.

METHODS

We conducted a prospective trial of GDFT following liver transplantation randomising patients with liver cirrhosis to either 12 h of GDFT using non-invasive cardiac output monitoring or standard care (SC). The primary outcome was feasibility. Secondary outcomes included survival, postoperative complications (Clavien-Dindo), quality of life (by EQ-5D-5L) and resource use. Trial specific follow up occurred at 90 and 180 days after surgery.

RESULTS

The study was feasible. Of 224 eligible patients, 122 were approached, 114 consented to participate and 60 were enrolled into the trial. The mean (SD) volume of IV crystalloid administered to the GDFT group during the 12-h study period was 3968 (2073) ml for the GDFT group and 2510 (1026) ml for the SC group. As regards secondary outcomes there was no difference in survival or overall complication rates. There was no significant difference in quality of life scores and resource use between the groups.

CONCLUSION

A randomised study of GDFT following liver transplantation is feasible. A post-trial stakeholder meeting supported proceeding with a full multi-centre trial.

Effect of cumulative fluid balance on acute kidney injury and patient outcomes after orthotopic liver transplantation: A retrospective cohort study

AIM

Acute kidney injury (AKI) is a serious complication following orthotopic liver transplantation (OLT) and it affects long-term patient survival. The aims of this study were to identify the effects of cumulative fluid balance (FB) on early post-OLT AKI and adverse outcomes and to construct a model to predict AKI.

METHODS

We retrospectively analysed 146 adult patients who underwent OLT. AKI severity was classified according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Univariate and multivariate logistic regression analyses were used to evaluate the association between cumulative FB and post-OLT AKI. The Kaplan-Meier method was used to estimate the survival rate.

RESULTS

Within the perioperative period of 72 hours, 50% (66/132) of patients developed AKI, with 36 (54%), 16 (24%) and 14 (21%) patients having AKI stages 1, 2 and 3, respectively. The cumulative FB was the risk factors for post-OLT AKI (odds ratio [OR], 1.011; 95% confidence interval [CI], 1.156~6.001; P = .021). Preoperative albumin was a protective factor for post-OLT AKI (OR, 0.309; 95% CI, 0.140~0.731; P = .007). The AKI group requires renal replacement therapy (RRT) more (15.2% vs 0%, P = .001) and associated with postoperative complications (56% vs 28.8%, P = .003). The complication-free survival was lower in the AKI group ([11.90 vs 18.74] months, χ² = 9.60, P = .002).

CONCLUSION

Cumulative FB within 72 hours is associated with post-OLT AKI and requires RRT. Cumulative FB impacts the long-term complication-free survival of the recipients.

Restrictive fluid management strategies and outcomes in liver transplantation: a systematic review

PURPOSE

Restrictive fluid management strategies have been proposed to reduce complications in liver transplant recipients. We conducted a systematic review to evaluate the effects of restrictive perioperative fluid management strategies, compared with liberal ones, on postoperative outcomes in adult liver transplant recipients. Our primary outcome was acute kidney injury (AKI). Our secondary outcomes were bleeding, mortality, and other postoperative complications.

SOURCE

We searched major databases (CINAHL, EMB Reviews, EMBASE, MEDLINE, and the grey literature) from their inception to 10 July 2018 for randomized-controlled trials (RCTs) and observational studies comparing two fluid management strategies (or observational studies reporting two outcomes with available data on fluid volume received) in adult liver transplant recipients. Study selection, data abstraction, and risk of bias assessment were performed by at least two investigators. Data from RCTs were pooled using risk ratios (RR) and mean differences (MD) with random-effect models.

PRINCIPAL FINDINGS

We found seven RCTs and 29 observational studies. Based on RCTs, fluid management strategies did not have any effect on AKI, mortality, or any other postoperative complications. Intraoperative RCTs suggested that a restrictive fluid management strategy reduced pulmonary complications (RR, 0.69; 95% confidence interval [CI], 0.47 to 0.99; n = 283; I² = 27%), duration of mechanical ventilation (MD, -13.04 hr; 95% CI, -22.2 to -3.88; n = 130; I² = 0%) and blood loss (MD, -1.14 L; 95% CI, -1.72 to -0.57; n = 151; I² = 0%).

CONCLUSION

Based on low or very low levels of evidence, we did not find any association between restrictive fluid management strategies and AKI, but we observed possible protective effects of intraoperative restrictive fluid management strategies on other outcomes.

TRIAL REGISTRATION

PROSPERO (CRD42017054970); registered 18 May, 2017.

Abdominal Organ Transplantation: Noteworthy Literature in 2018

A PubMed search revealed 1382 articles on pancreatic transplantation, 781 on intestinal transplantation, more than 7200 on kidney transplantation, and more than 5500 on liver transplantation published between January 1, 2018, and December 31, 2018. After narrowing the list down to human studies, 436 pancreatic, 302 intestinal, 1920 liver, and more than 2000 kidney transplantation studies were screened for inclusion in this review.

Association Between Perioperative Fluid Balance and 30-Day Unplanned Readmission After Major Abdominal Surgery

Perioperative positive fluid balance (FB) increases postoperative complication and length of hospital stay. We aimed to investigate 30-day unplanned readmission after major abdominal surgery based on perioperative FB (%) on postoperative days (POD) 0 to 3. This retrospective cohort study analyzed medical records of patients who underwent elective major abdominal surgery (surgery time >2 hours, estimated blood loss >500 mL) at a single tertiary academic hospital from January 2010 to December 2017. Cumulative FB was calculated by total input fluid - output fluid in liters × weight (kg)^-1 on admission × 100 during POD 0 (24 hours), 0 to 1 (48 hours), 0 to 2 (72 hours), and 0 to 3 (96 hours). Of the 3650 patients in the final analysis, 503 (13.8%) had unplanned readmission within 30 days. In the multivariable logistic regression analysis, FB on POD 0 (24 hours), 0 to 1 (48 hours), 0 to 2 (72 hours), and 0 to 3 (96 hours) showed no significant association with 30-day unplanned readmission (all P > .05). However, an increase of 10 000 points in the total relative value unit scores was associated with 5% increase in 30-day unplanned readmission (odds ratio = 1.05, 95% confidence interval = 1.02-1.07; P = .001), and 1-hour increase in surgery time was associated with 10% increase in 30-day unplanned readmission (odds ratio = 1.10, 95% confidence interval = 1.05-1.15; P < .001). This study showed that perioperative FB is not associated with 30-day unplanned readmission rate after a major abdominal surgery. Total relative value unit scores and duration of surgery were significantly associated with 30-day unplanned readmission rate after major abdominal surgery in a single tertiary academic hospital.