Effect of High-Volume Hemofiltration in Critically Ill Patients: A Systematic Review and Meta-Analysis

American Burn Association Clinical Practice Guidelines on Burn Shock Resuscitation

This Clinical Practice Guideline (CPG) addresses the topic of acute fluid resuscitation during the first 48 hours following a burn injury for adults with burns ≥20% of the total body surface area (%TBSA). The listed authors formed an investigation panel and developed clinically relevant PICO (Population, Intervention, Comparator, Outcome) questions. A systematic literature search returned 5978 titles related to this topic and after 3 levels of screening, 24 studies met criteria to address the PICO questions and were critically reviewed. We recommend that clinicians consider the use of human albumin solution, especially in patients with larger burns, to lower resuscitation volumes and improve urine output. We recommend initiating resuscitation based on providing 2 mL/kg/% TBSA burn in order to reduce resuscitation fluid volumes. We recommend selective monitoring of intra-abdominal and intraocular pressure during burn shock resuscitation. We make a weak recommendation for clinicians to consider the use of computer decision support software to guide fluid titration and lower resuscitation fluid volumes. We do not recommend the use of transpulmonary thermodilution-derived variables to guide burn shock resuscitation. We are unable to make any recommendations on the use of high-dose vitamin C (ascorbic acid), fresh frozen plasma (FFP), early continuous renal replacement therapy, or vasopressors as adjuncts during acute burn shock resuscitation. Mortality is an important outcome in burn shock resuscitation, but it was not formally included as a PICO outcome because the available scientific literature is missing studies of sufficient population size and quality to allow us to confidently make recommendations related to the outcome of survival at this time.

Extracorporeal blood purification strategies in sepsis and septic shock: An insight into recent advancements

BACKGROUND

Despite various therapies to treat sepsis, it is one of the leading causes of mortality in the intensive care unit patients globally. Knowledge about the pathophysiology of sepsis has sparked interest in extracorporeal therapies (ECT) which are intended to balance the dysregulation of the immune system by removing excessive levels of inflammatory mediators.

AIM

To review recent data on the use of ECT in sepsis and to assess their effects on various inflammatory and clinical outcomes.

METHODS

In this review, an extensive English literature search was conducted from the last two decades to identify the use of ECT in sepsis. A total of 68 articles from peer-reviewed and indexed journals were selected excluding publications with only abstracts.

RESULTS

Results showed that ECT techniques such as high-volume hemofiltration, coupled plasma adsorption/filtration, resin or polymer adsorbers, and CytoSorb^® are emerging as adjunct therapies to improve hemodynamic stability in sepsis. CytoSorb^® has the most published data in regard to the use in the field of septic shock with reports on improved survival rates and lowered sequential organ failure assessment scores, lactate levels, total leucocyte count, platelet count, interleukin- IL-6, IL-10, and TNF levels.

CONCLUSION

Clinical acceptance of ECT in sepsis and septic shock is currently still limited due to a lack of large random clinical trials. In addition to patient-tailored therapies, future research developments with therapies targeting the cellular level of the immune response are expected.

Early High-dose Continuous Veno-venous Hemofiltration Alleviates the Alterations of CD4+ T Lymphocyte Subsets in Septic Patients Combined with Acute Kidney Injury

BACKGROUND

This study aims to determine whether early high-dose continuous venous-venous hemofiltration (CVVH) alleviates the alterations in CD4⁺ T lymphocyte subsets in septic patients combined with acute kidney injury.

METHODS

Enrolled septic patients combined with acute kidney injury were randomized into CVVH (n = 50) and conventional treatment (non-CVVH, n = 53) groups. Healthy volunteers (n = 21) were enrolled. CVVH was initiated within 12 h of intensive care unit (ICU) admission with the doses of 35 ~ 60 mL/kg/h and maintained for at least 72 h. Th1, Th2, Th17 and T_reg were measured by flow cytometry on days 1, 3 and 7 of ICU admission. Sequential organ failure assessment (SOFA) scores were calculated.

RESULTS

Th1 percentages and Th1/Th2 ratios were lower, and Th2, Th17 and T_reg percentages and Th17/T_reg ratios were higher in septic patients compared to healthy volunteers. CVVH significantly increased Th1 percentages and Th1/Th2 ratios, and significantly decreased Th2, Th17 and T_reg percentages and Th17/T_reg ratios compared to non-CVVH. Th1 percentages and Th1/Th2 ratios were negatively correlated with SOFA scores, while Th2, Th17 and T_reg percentages and Th17/T_reg ratios were positively correlated with SOFA scores. Patients with CVVH had significantly lower SOFA scores on day 7 of ICU admission and a shorter ICU stay compared to those with non-CVVH.

CONCLUSIONS

Septic patients combined with acute kidney injury exhibit different alterations of CD4⁺ T lymphocyte subsets. Early high-dose CVVH alleviates the alterations, which may be one of factors associated with improved sepsis severity.

Sepsis-Pathophysiology and Therapeutic Concepts

Sepsis is a life-threatening condition and a global disease burden. Today, the heterogeneous syndrome is defined as severe organ dysfunction caused by a dysregulated host response to infection, with renewed emphasis on immune pathophysiology. Despite all efforts of experimental and clinical research during the last three decades, the ability to positively influence course and outcome of the syndrome remains limited. Evidence-based therapy still consists of basic causal and supportive measures, while adjuvant interventions such as blood purification or targeted immunotherapy largely remain without proof of effectiveness so far. With this review, we aim to provide an overview of sepsis immune pathophysiology, to update the choice of therapeutic approaches targeting different immunological mechanisms in the course of sepsis and septic shock, and to call for a paradigm shift from the pathogen to the host response as a potentially more promising angle.

Continuous Venovenous Hemofiltration is Associated with Improved Survival in Burn Patients with Shock: A Subset Analysis of a Multicenter Observational Study

INTRODUCTION

Acute kidney injury (AKI) is associated with high mortality in burn patients. Previously, we reported that timely initiation of renal replacement therapy (RRT) with an individualized preference toward continuous modes at relatively higher than recommended doses has become standard practice in critically ill burn patients with AKI and is associated with a historically low mortality. The purpose of this cohort analysis was to determine if modality choice impacted survival in burn patients.

METHODS

After Institutional Review Board approval, a subset analysis was performed on de-identified data collected during a multicenter, observational study. All patients (n = 170) were 18 years or older, admitted with severe burn injuries and started on RRT. Comparisons were made utilizing χ2 or Fisher's exact test. Kaplan-Meier plots were utilized to assess survival. Sample size determinations to aid future research were calculated utilizing χ2 test with a Yates Correction Factor.

RESULTS

Demographics and revised Baux were similar between groups. When continuous venovenous hemofiltration (CVVH) was compared to all other modalities, there was no statistically significant difference in survival (56 vs. 43%, p = 0.124). However, survival was significantly improved (54 vs. 37%, p = 0.032) in the subset of patients requiring vasopressors (n = 77). There was no statistically significant survival difference in patients with inhalation injury (38 vs. 29%, p = 0.638) or acute lung injury/acute respiratory distress syndrome (51 vs. 33%, p = 0.11).

DISCUSSION/CONCLUSION

Survival may be improved if CVVH is chosen as the preferred modality in burn patients with shock and requiring RRT. Differences in other subsets were promising, but analysis was underpowered. Further research should determine if modality choice provides survival benefit in any other subset of burn injury.