Extracorporeal Therapies in the Treatment of Sepsis: Experience and Promise

Venoarterial Extracorporeal Membrane Oxygenation Implementation in Septic Shock Rat Model

Septic shock, a global health concern, boasts high mortality rates. Research exploring the efficacy of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in septic shock remains limited. Our study aimed to establish a rodent model employing VA-ECMO in septic shock rats, assessing the therapeutic impact of VA-ECMO on septic shock. Nineteen Sprague-Dawley rats were randomly assigned to sham, septic shock, and (septic shock + VA-ECMO; SSE) groups. Septic shock was induced by intravenous lipopolysaccharides, confirmed by a mean arterial pressure drop to 25-30% of baseline. Rats in the SSE group received 2 hours of VA-ECMO support and 60 minutes of post-weaning ventilation. Sham and septic shock groups underwent mechanical ventilation for equivalent durations. Invasive mean arterial pressure monitoring, echocardiographic examinations, and blood gas analysis revealed the efficacy of VA-ECMO in restoring circulation and ensuring adequate tissue oxygenation in septic shock rats. Post-experiment pathology exhibited the potential of VA-ECMO in mitigating major organ injury. In summary, our study successfully established a stable septic shock rat model with the implementation of VA-ECMO, offering a valuable platform to explore molecular mechanisms underlying VA-ECMO's impact on septic shock.

Analysis of uroseptic shock after ureteroscopy for ureteral calculi during pregnancy: a case report

BACKGROUND

Uroseptic shock secondary to ureteral calculi during pregnancy is rare. It is characterized by rapid onset, rapid progression, aggressive disease, limited treatment, poor prognosis, and a mortality rate higher than 20% with improper or delayed management. A clear diagnosis is made based on typical clinical symptoms and abdominal ultrasound, often requiring combined multidisciplinary treatment and the simultaneous release of the obstruction. The high mortality rate is mainly related to inappropriate early treatment of stones and infections or failure to intervene in a timely manner.

CASE PRESENTATION

A 21-year-old first-time pregnant patient with uroseptic shock was admitted to our intensive care unit. The patient was successfully treated at our hospital with multidisciplinary cooperation, high-dose vasoactive drugs, IABP, CRRT, VA-ECMO, and termination of pregnancy.

CONCLUSIONS

Timely relief of obstructions, termination of pregnancy, and the provision of IABP, CRRT, and VA-ECMO when necessary in critically ill patients with uroseptic shock during pregnancy can improve the success rate of resuscitation.

Adjustments to pharmacologic therapies for hemophagocytic lymphohistiocytosis while on extracorporeal support

Hemophagocytic lymphohistiocytosis (HLH) is an immune dysregulatory syndrome characterized by severe inflammation and end-organ damage. Due to significant organ dysfunction, patients often require extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT). In this report, we describe consideration for adjusting treatment in the context of extracorporeal organ support. We describe agents commonly used and dosing adjustments made in light of extracorporeal organ support. We report six cases that illustrate the feasibility of initiating standard HLH therapies in patients requiring these modalities.

A Systematic Review of Preexisting Sepsis and Extracorporeal Membrane Oxygenation

We retrospectively reviewed all pertinent extracorporeal membrane oxygenation (ECMO) studies (January 1995 to September 2017) of adults with sepsis as a primary indication for intervention and its association with morbidity and mortality. Collected data included study type, ECMO configuration, outcomes, effect size, and other features. Advanced age was a risk factor for death. Compared with nonsurvivors, survivors had a lower median Sepsis-Related Organ Failure Assessment score on day 3 (15 vs. 18, p = 0.01). Biomarkers in survivors and nonsurvivors, respectively, were peak lactate (from two studies: 4.5 vs. 15.1 mmol/L, p = 0.03; 3.6 ± 3.7 vs. 3.3 ± 2.4 mmol/L, p = 0.850) and procalcitonin levels (41 vs. 164 ng/ml, p = 0.008). Bacteremia was associated with catheter colonization, and 90.5% of a group without bloodstream infections survived to discharge; ECMO weaning was possible for less than half the bloodstream infection group. Myocarditis portended favorable outcomes for patients with sepsis who received ECMO. Extracorporeal membrane oxygenation was used in immunosuppressed patients with refractory cardiopulmonary insufficiency from severe sepsis with successful weaning from ECMO for most patients. Overall survival varied substantially among studies (15.38-71.43%). Existing studies do not present well-defined patterns supporting use of ECMO in sepsis because of sample sizes and disparate study designs.

Extracorporeal Membrane Oxygenation for Group B Streptococcal Sepsis in Neonates: A Retrospective Study of the Extracorporeal Life Support Organization Registry

OBJECTIVES

Neonatal group B streptococcal sepsis remains a leading cause of neonatal sepsis globally and is characterized by unique epidemiologic features. Extracorporeal membrane oxygenation has been recommended for neonatal septic shock refractory to conventional management, but data on extracorporeal membrane oxygenation in group B streptococcal sepsis are scarce. We aimed to assess outcomes of extracorporeal membrane oxygenation in neonates with group B streptococcal sepsis.

DESIGN

Retrospective study of the international registry of the Extracorporeal Life Support Organization.

SETTING

Extracorporeal membrane oxygenation centers contributing to Extracorporeal Life Support Organization registry.

PATIENTS

Patients less than or equal to 30 days treated with extracorporeal membrane oxygenation and a diagnostic code of group B streptococcal sepsis between January 1, 2007, and December 31, 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

In-hospital mortality was the primary outcome. Univariable and multivariable logistic regression models to predict mortality were established. One hundred ninety-two runs in 191 neonates were identified meeting eligibility criteria, of which 55 of 191 (29%) died. One hundred thirty-seven (71%) were treated with venoarterial extracorporeal membrane oxygenation. One hundred sixty-nine runs (88%) occurred during the first week of life for early-onset sepsis and 23 (12%) after 7 days of life. The in-hospital mortality for extracorporeal membrane oxygenation used after 7 days of life was significantly higher compared with early-onset sepsis (65% vs 24%; p < 0.01). In addition, lower weight, lower pH, lower bicarbonate, and surfactant administration precannulation were significantly associated with mortality (p < 0.05). Adjusted analyses confirmed that age greater than 7 days, lower weight, and lower pH were associated with higher mortality (p < 0.05). One hundred fifty-one of 192 runs (79%) experienced a major complication. The number of major complications during extracorporeal membrane oxygenation was associated significantly with mortality (p < 0.001; adjusted odds ratio, 1.27 [1.08-1.49; p = 0.004]).

CONCLUSIONS

This large registry-based study indicates that treatment with extracorporeal membrane oxygenation for neonatal group B streptococcal sepsis is associated with survival in the majority of patients. Future quality improvement interventions should aim to reduce the burden of major extracorporeal membrane oxygenation-associated complications which affected four out of five neonatal group B streptococcal sepsis extracorporeal membrane oxygenation patients.

Extracorporeal Membrane Oxygenation in the Treatment of Severe Pulmonary and Cardiac Compromise in Coronavirus Disease 2019: Experience with 32 Patients

As coronavirus disease 2019 (COVID-19) cases surge worldwide, an urgent need exists to enhance our understanding of the role of extracorporeal membrane oxygenation (ECMO) in the management of severely ill patients with COVID-19 who develop acute respiratory and cardiac compromise refractory to conventional therapy. The purpose of this manuscript is to review our initial clinical experience in 32 patients with confirmed COVID-19 treated with ECMO. A multi-institutional registry and database was created and utilized to assess all patients who were supported with ECMO provided by SpecialtyCare. Data captured included patient characteristics, pre-COVID-19 risk factors and comorbidities, confirmation of COVID-19 diagnosis, features of ECMO support, specific medications utilized to treat COVID-19, and short-term outcomes through hospital discharge. This analysis includes all of our patients with COVID-19 supported with ECMO, with an analytic window starting March 17, 2020, when our first COVID-19 patient was placed on ECMO, and ending April 9, 2020. During the 24 days of this study, 32 consecutive patients with COVID-19 were placed on ECMO at nine different hospitals. As of the time of analysis, 17 remain on ECMO, 10 died before or shortly after decannulation, and five are alive and extubated after removal from ECMO, with one of these five discharged from the hospital. Adjunctive medication in the surviving patients while on ECMO was as follows: four of five survivors received intravenous steroids, three of five survivors received antiviral medications (Remdesivir), two of five survivors were treated with anti-interleukin-6-receptor monoclonal antibodies (Tocilizumab or Sarilumab), and one of five survivors received hydroxychloroquine. An analysis of 32 COVID-19 patients with severe pulmonary compromise supported with ECMO suggests that ECMO may play a useful role in salvaging select critically ill patients with COVID-19. Additional patient experience and associated clinical and laboratory data must be obtained to further define the optimal role of ECMO in patients with COVID-19 and acute respiratory distress syndrome (ARDS). These initial data may provide useful information to help define the best strategies to care for these challenging patients and may also provide a framework for much-needed future research about the use of ECMO to treat patients with COVID-19.

Defining benefit threshold for extracorporeal membrane oxygenation in children with sepsis-a binational multicenter cohort study

BACKGROUND

The surviving sepsis campaign recommends consideration for extracorporeal membrane oxygenation (ECMO) in refractory septic shock. We aimed to define the benefit threshold of ECMO in pediatric septic shock.

METHODS

Retrospective binational multicenter cohort study of all ICUs contributing to the Australian and New Zealand Paediatric Intensive Care Registry. We included patients < 16 years admitted to ICU with sepsis and septic shock between 2002 and 2016. Sepsis-specific risk-adjusted models to establish ECMO benefit thresholds with mortality as the primary outcome were performed. Models were based on clinical variables available early after admission to ICU. Multivariate analyses were performed to identify predictors of survival in children treated with ECMO.

RESULTS

Five thousand sixty-two children with sepsis and septic shock met eligibility criteria, of which 80 (1.6%) were treated with veno-arterial ECMO. A model based on 12 clinical variables predicted mortality with an AUROC of 0.879 (95% CI 0.864-0.895). The benefit threshold was calculated as 47.1% predicted risk of mortality. The observed mortality for children treated with ECMO below the threshold was 41.8% (23 deaths), compared to a predicted mortality of 30.0% as per the baseline model (16.5 deaths; standardized mortality rate 1.40, 95% CI 0.89-2.09). Among patients above the benefit threshold, the observed mortality was 52.0% (13 deaths) compared to 68.2% as per the baseline model (16.5 deaths; standardized mortality rate 0.61, 95% CI 0.39-0.92). Multivariable analyses identified lower lactate, the absence of cardiac arrest prior to ECMO, and the central cannulation (OR 0.31, 95% CI 0.10-0.98, p = 0.046) as significant predictors of survival for those treated with VA-ECMO.

CONCLUSIONS

This binational study demonstrates that a rapidly available sepsis mortality prediction model can define thresholds for survival benefit in children with septic shock considered for ECMO. Survival on ECMO was associated with central cannulation. Our findings suggest that a fully powered RCT on ECMO in sepsis is unlikely to be feasible.

ECMO with vasopressor use during early endotoxic shock: Can it improve circulatory support and regional microcirculatory blood flow?

Introduction

While extracorporeal membrane oxygenation (ECMO) is effective in preventing further hypoxemia and maintains blood flow in endotoxin-induced shock, ECMO alone does not reverse the hypotension. In this study, we tested whether concurrent vasopressor use with ECMO would provide increased circulatory support and blood flow, and characterized regional blood flow distribution to vital organs.

Methods

Endotoxic shock was induced in piglets to achieve a 30% decrease in mean arterial pressure (MAP). Measurements of untreated pigs were compared to pigs treated with ECMO alone or ECMO and vasopressors.

Results

ECMO provided cardiac support during vasodilatory endotoxic shock and improved oxygen delivery, but vasopressor therapy was required to return MAP to normotensive levels. Increased blood pressure with vasopressors did not alter oxygen consumption or extraction compared to ECMO alone. Regional microcirculatory blood flow (RBF) to the brain, kidney, and liver were maintained or increased during ECMO with and without vasopressors.

Conclusion

ECMO support and concurrent vasopressor use improve regional blood flow and oxygen delivery even in the absence of full blood pressure restoration. Vasopressor-induced selective distribution of blood flow to vital organs is retained when vasopressors are administered with ECMO.

ECMO Maintains Cerebral Blood Flow During Endotoxic Shock in Piglets

Cerebrovascular injury while on extracorporeal membrane oxygenation (ECMO) may be caused by excessive brain perfusion during hypoxemic reperfusion. Previous studies have postulated that the most vulnerable period of time for cerebrovascular injury is during the transfer period to ECMO. Therefore, our objective was to compare brain perfusion and hemodynamics in a piglet endotoxic shock ECMO model. The effect of ECMO flow on microcirculation of different brain regions was compared between 10 control pigs and six pigs (7–10 kg) administered IV endotoxin to achieve a drop in mean arterial blood pressure (MAP) of at least 30%. Cardiac output (CO), brain oxygen utilization, and microcirculatory blood flow (BF) were compared at baseline and 2 hours after ECMO stabilization. Matching ECMO delivery with baseline CO in control animals increased perfusion (p < 0.05) in all areas of the brain. In contrast, with endotoxin, ECMO returned perfusion closer to baseline levels in all regions of the brain and maintained brain tissue oxygen consumption. Both control and endotoxic pigs showed no evidence of acute neuronal necrosis in histologic cerebral cortical sections examined after 2 hours of ECMO. Results show that during endotoxic shock, transition to ECMO can maintain brain BF equally to all brain regions without causing overperfusion, and does not appear to cause brain tissue histopathologic changes (hemorrhage or necrosis) during the acute stabilization period after ECMO induction.

American College of Critical Care Medicine Clinical Practice Parameters for Hemodynamic Support of Pediatric and Neonatal Septic Shock

OBJECTIVES

The American College of Critical Care Medicine provided 2002 and 2007 guidelines for hemodynamic support of newborn and pediatric septic shock. Provide the 2014 update of the 2007 American College of Critical Care Medicine "Clinical Guidelines for Hemodynamic Support of Neonates and Children with Septic Shock."

DESIGN

Society of Critical Care Medicine members were identified from general solicitation at Society of Critical Care Medicine Educational and Scientific Symposia (2006-2014). The PubMed/Medline/Embase literature (2006-14) was searched by the Society of Critical Care Medicine librarian using the keywords: sepsis, septicemia, septic shock, endotoxemia, persistent pulmonary hypertension, nitric oxide, extracorporeal membrane oxygenation, and American College of Critical Care Medicine guidelines in the newborn and pediatric age groups.

MEASUREMENTS AND MAIN RESULTS

The 2002 and 2007 guidelines were widely disseminated, translated into Spanish and Portuguese, and incorporated into Society of Critical Care Medicine and American Heart Association/Pediatric Advanced Life Support sanctioned recommendations. The review of new literature highlights two tertiary pediatric centers that implemented quality improvement initiatives to improve early septic shock recognition and first-hour compliance to these guidelines. Improved compliance reduced hospital mortality from 4% to 2%. Analysis of Global Sepsis Initiative data in resource rich developed and developing nations further showed improved hospital mortality with compliance to first-hour and stabilization guideline recommendations.

CONCLUSIONS

The major new recommendation in the 2014 update is consideration of institution-specific use of 1) a "recognition bundle" containing a trigger tool for rapid identification of patients with septic shock, 2) a "resuscitation and stabilization bundle" to help adherence to best practice principles, and 3) a "performance bundle" to identify and overcome perceived barriers to the pursuit of best practice principles.

Extracorporeal Life Support: Four Decades and Counting

Extracorporeal membrane oxygenation (ECMO) or extracorporeal life support (ECLS) is a form of heart lung bypass that is used to support neonates, pediatrics, and adult patients with cardiorespiratory failure for days or weeks till organ recovery or transplantation. Venoarterial (VA) and venovenous (VV) ECLS are the most common modes of support. ECLS circuit components and monitoring have been evolving over the last 40 years. The technology is safer, simpler, and more durable with fewer complications. The use of neonatal respiratory ECLS use has been declining over the last two decades, while adult respiratory ECLS is growing especially since the H1N1 influenza pandemic in 2009. This review provides an overview of ECLS evolution over the last four decades, its use in neonatal, pediatric and adults, description of basic principles, circuit components, complications, and outcomes as well as a quick look into the future.

Pediatric Multiple Organ Dysfunction Syndrome: Promising Therapies

OBJECTIVE

To describe the state of the science, identify knowledge gaps, and offer potential future research questions regarding promising therapies for children with multiple organ dysfunction syndrome presented during the Eunice Kennedy Shriver National Institute of Child Health and Human Development Workshop on Pediatric Multiple Organ Dysfunction Syndrome (March 26-27, 2015).

DATA SOURCES

Literature review, research data, and expert opinion.

STUDY SELECTION

Not applicable.

DATA EXTRACTION

Moderated by an expert from the field, issues relevant to the association of multiple organ dysfunction syndrome with a variety of conditions were presented, discussed, and debated with a focus on identifying knowledge gaps and research priorities.

DATA SYNTHESIS

Summary of presentations and discussion supported and supplemented by relevant literature.

CONCLUSIONS

Among critically ill children, multiple organ dysfunction syndrome is relatively common and associated with significant morbidity and mortality. For outcomes to improve, effective therapies aimed at preventing and treating this condition must be discovered and rigorously evaluated. In this article, a number of potential opportunities to enhance current care are highlighted including the need for a better understanding of the pharmacokinetics and pharmacodynamics of medications, the effect of early and optimized nutrition, and the impact of effective glucose control in the setting of multiple organ dysfunction syndrome. Additionally, a handful of the promising therapies either currently being implemented or developed are described. These include extracorporeal therapies, anticytokine therapies, antitoxin treatments, antioxidant approaches, and multiple forms of exogenous steroids. For the field to advance, promising therapies and other therapies must be assessed in rigorous manner and implemented accordingly.

The efficacy and safety of plasma exchange in patients with sepsis and septic shock: a systematic review and meta-analysis

Introduction

Sepsis and septic shock are leading causes of intensive care unit (ICU) mortality. They are characterized by excessive inflammation, upregulation of procoagulant proteins and depletion of natural anticoagulants. Plasma exchange has the potential to improve survival in sepsis by removing inflammatory cytokines and restoring deficient plasma proteins. The objective of this study is to evaluate the efficacy and safety of plasma exchange in patients with sepsis.

Methods

We searched MEDLINE, EMBASE, CENTRAL, Scopus, reference lists of relevant articles, and grey literature for relevant citations. We included randomized controlled trials comparing plasma exchange or plasma filtration with usual care in critically ill patients with sepsis or septic shock. Two reviewers independently identified trials, extracted trial-level data and performed risk of bias assessments using the Cochrane Risk of Bias tool. The primary outcome was all-cause mortality reported at longest follow-up. Meta-analysis was performed using a random-effects model.

Results

Of 1,957 records identified, we included four unique trials enrolling a total of 194 patients (one enrolling adults only, two enrolling children only, one enrolling adults and children). The mean age of adult patients ranged from 38 to 53 years (n = 128) and the mean age of children ranged from 0.9 to 18 years (n = 66). All trials were at unclear to high risk of bias. The use of plasma exchange was not associated with a significant reduction in all-cause mortality (risk ratio (RR) 0.83, 95% confidence interval (CI) 0.45 to 1.52, I² 60%). In adults, plasma exchange was associated with reduced mortality (RR 0.63, 95% CI 0.42 to 0.96; I² 0%), but was not in children (RR 0.96, 95% CI 0.28 to 3.38; I² 60%). None of the trials reported ICU or hospital lengths of stay. Only one trial reported adverse events associated with plasma exchange including six episodes of hypotension and one allergic reaction to fresh frozen plasma.

Conclusions

Insufficient evidence exists to recommend plasma exchange as an adjunctive therapy for patients with sepsis or septic shock. Rigorous randomized controlled trials evaluating clinically relevant patient-centered outcomes are required to evaluate the impact of plasma exchange in this condition.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0699-2) contains supplementary material, which is available to authorized users.

Effects of continuous renal replacement therapy on intestinal mucosal barrier function during extracorporeal membrane oxygenation in a porcine model

Backgrounds

Extracorporeal membrane oxygenation (ECMO) has been recommended for treatment of acute, potentially reversible, life-threatening respiratory failure unresponsive to conventional therapy. Intestinal mucosal barrier dysfunction is one of the most critical pathophysiological disorders during ECMO. This study aimed to determine whether combination with CRRT could alleviate damage of intestinal mucosal barrier function during VV ECMO in a porcine model.

Methods

Twenty-four piglets were randomly divided into control(C), sham(S), ECMO(E) and ECMO + CRRT(EC) group. The animals were treated with ECMO or ECMO + CRRT for 24 hours. After the experiments, piglets were sacrificed. Jejunum, ileum and colon were harvested for morphologic examination of mucosal injury and ultrastructural distortion. Histological scoring was assessed according to Chiu’s scoring standard. Blood samples were taken from the animals at -1, 2, 6, 12 and 24 h during experiment. Blood, liver, spleen, kidney and mesenteric lymphnode were collected for bacterial culture. Serum concentrations of diamine oxidase (DAO) and intestinal fatty acid binding protein (I-FABP) were tested as markers to assess intestinal epithelial function and permeability. DAO levels were determined by spectrophotometry and I-FABP levels by enzyme linked immunosorbent assay.

Results

Microscopy findings showed that ECMO-induced intestinal microvillus shedding and edema, morphological distortion of tight junction between intestinal mucous epithelium and loose cell-cell junctions were significantly improved with combination of CRRT. No significance was detected on positive rate of serum bacterial culture. The elevated colonies of bacterial culture in liver and mesenteric lymphnode in E group reduced significantly in EC group (p < 0.05). Compared with E group, EC group showed significantly decreased level of serum DAO and I-FABP (p < 0.05).

Conclusions

CRRT can alleviate the intestinal mucosal dysfunction and bacterial translocation during VV ECMO, which may extenuate the ECMO-associated SIRS and raise the clinical effect and safety.

Acute kidney injury in children: an update on diagnosis and treatment

The concept and definition of acute kidney injury (AKI) in adults and children has undergone significant change in recent years. Biomarker assessment is aiding in description, defining and understanding timing of AKI. AKI demonstrates unique characteristics in association with sepsis and septic shock, organ dysfunction, and fluid overload. Treatment remains problematic, but growing experience with pediatric continuous renal replacement therapies has improved the delivery of care in children. Increasingly, continuous renal replacement therapy is provided in combination with other extracorporeal technologies, and approaches are advancing to improve combined therapy use.

A case series of the successful use of ECMO, continuous renal replacement therapy, and plasma exchange for thrombocytopenia-associated multiple organ failure

We present three cases of pediatric patients with thrombocytopenia-associated multiple organ failure and the evidence for providing extracorporeal organ support. All three patients had severe cardiac dysfunction, respiratory failure, and acute kidney injury treated with venoarterial extracorporeal membrane oxygenation, continuous renal replacement therapy, and plasma exchange. Despite the presence of multiple organ failure and high risk of mortality, all three patients survived with minimal long-term sequelae.

Pediatric sepsis: challenges and adjunctive therapies

Sepsis remains an important challenge in pediatric critical care medicine. This review provides an appraisal of adjunctive therapies for sepsis and highlights opportunities for meeting selected challenges in the field. Future clinical studies should address long-term and functional outcomes as well as acute outcomes. Potential adjunctive therapies such as corticosteroids, hemofiltration, hemoadsorption, and plasmapheresis may have important roles, but still require formal and more rigorous testing by way of clinical trials. Finally, the design of future clinical trials should consider novel approaches for stratifying outcome risks as a means of improving the risk-to-benefit ratio of experimental therapies.

Continuous renal replacement therapy to reduce inflammation in a piglet hemorrhage-reperfusion extracorporeal membrane oxygenation model

BACKGROUND

During extracorporeal membrane oxygenation (ECMO), circulation of blood across synthetic surfaces triggers an inflammatory response. Therefore, we evaluated the ability of continuous renal replacement therapy (CRRT) to remove cytokines and reduce the inflammatory response in a piglet hemorrhage-reperfusion ECMO model.

METHODS

Three groups were studied: (i) uninjured controls (n = 11); (ii) hemorrhage-reperfusion while on venoarterial ECMO (30% hemorrhage with subsequent blood volume replacement within 60 min) (n = 8); (iii) treatment with CRRT after hemorrhage-reperfusion while on ECMO (n = 7). Hemodynamic parameters, oxygen utilization, and plasma and broncho-alveolar lavage (BAL) cytokine levels were recorded and lung tissue samples collected for histologic comparison.

RESULTS

Whereas mean arterial pressures decreased among hemorrhage-reperfusion piglets, ECMO with CRRT did not significantly alter mean arterial pressures or systemic vascular resistance and was able to maintain blood flow as well as oxygen delivery after hemorrhage-reperfusion. Plasma interleukin (IL)-6 and IL-10, and BAL tumor necrosis factor (TNF)-α, IL-1β, IL-6, IL-8, and IL-10 increased as a result of hemorrhage-reperfusion while on ECMO. After a 6-h period of CRRT, plasma IL-6 and BAL TNF-α, IL-6, and IL-8 levels decreased.

CONCLUSION

Data suggest CRRT may decrease inflammatory cytokine levels during the initial phase of ECMO therapy following hemorrhage-reperfusion while maintaining cardiac output and oxygen utilization.

Panton-Valentine leukocidin-associated Staphylococcus aureus necrotizing pneumonia in infants: a report of four cases and review of the literature

Four children under 16 months of age presented within an 18-month period with severe, rapidly progressive Panton-Valentine leukocidin-associated ST93 Staphylococcus aureus necrotizing pneumonia. Two of the cases that required extracorporeal membranous oxygenation and proved fatal had poor prognostic features of leukopenia, rash and pulmonary haemorrhage. All four cases had recent contact with S. aureus infection in a family member. Reported cases of S. aureus necrotizing pneumonia in infants are reviewed, and approach to management is discussed.

World Federation of Pediatric Intensive Care and Critical Care Societies: Global Sepsis Initiative

BACKGROUND

According to World Health Organization estimates, sepsis accounts for 60%-80% of lost lives per year in childhood. Measures appropriate for resource-scarce and resource-abundant settings alike can reduce sepsis deaths. In this regard, the World Federation of Pediatric Intensive Care and Critical Care Societies Board of Directors announces the Global Pediatric Sepsis Initiative, a quality improvement program designed to improve quality of care for children with sepsis.

OBJECTIVES

To announce the global sepsis initiative; to justify some of the bundles that are included; and to show some preliminary data and encourage participation.

METHODS

The Global Pediatric Sepsis Initiative is developed as a Web-based education, demonstration, and pyramid bundles/checklist tool (http://www.pediatricsepsis.org or http://www.wfpiccs.org). Four health resource categories are included. Category A involves a nonindustrialized setting with mortality rate <5 yrs and >30 of 1,000 children. Category B involves a nonindustrialized setting with mortality rate <5 yrs and <30 of 1,000 children. Category C involves a developing industrialized nation. In category D, developed industrialized nation are determined and separate accompanying administrative and clinical parameters bundles or checklist quality improvement recommendations are provided, requiring greater resources and tasks as resource allocation increased from groups A to D, respectively.

RESULTS

In the vanguard phase, data for 361 children (category A, n = 34; category B, n = 12; category C, n = 84; category D, n = 231) were successfully entered, and quality-assurance reports were sent to the 23 participating international centers. Analysis of bundles for categories C and D showed that reduction in mortality was associated with compliance with the resuscitation (odds ratio, 0.369; 95% confidence interval, 0.188-0.724; p < .0004) and intensive care unit management (odds ratio, 0.277; 95% confidence interval, 0.096-0.80) bundles.

CONCLUSIONS

The World Federation of Pediatric Intensive Care and Critical Care Societies Global Pediatric Sepsis Initiative is online. Success in reducing pediatric mortality and morbidity, evaluated yearly as a measure of global child health care quality improvement, requires ongoing active recruitment of international participant centers. Please join us at http://www.pediatricsepsis.org or http://www.wfpiccs.org.

Use of therapeutic plasma exchange as a rescue therapy in 2009 pH1N1 influenza A--an associated respiratory failure and hemodynamic shock

OBJECTIVE

Acute pneumonitis with acute lung injury is a cause of significant mortality related to the 2009 pH1N1 influenza A virus. Widespread lung inflammation and increased pulmonary vascular permeability has been noted on autopsy. Also, many of these patients present with significant hemodynamic compromise suggesting systemic cytokine release. Therefore, attenuating circulating cytokines, and other mediators, by blood purification techniques is a theoretically attractive strategy. We report the use therapeutic plasma exchange in three children with 2009 H1N1 related acute lung injury with severe hemodynamic compromise that had failed conventional therapeutic interventions.

DESIGN

Case series.

SETTING

Pediatric intensive care unit in a university children's hospital.

PATIENTS

Three children, aged 8, 11, and 17 yrs, with acute respiratory distress syndrome and hemodynamic compromise related to the 2009 pH1N1 influenza A virus documented by polymerase chair reaction. All patients were on mechanical ventilation and inhaled nitric oxide, and one patient was on extracorporeal membrane oxygenation. Therapeutic plasma exchange was used as a rescue strategy.

INTERVENTIONS

Each patient received three exchanges of 35-40 mL/kg on consecutive days.

MEASUREMENTS

All three patients had dramatic reduction in pediatric logistic organ dysfunction scores, oxygen requirements, and vasopressor requirements after two exchanges. All survived with good functional recovery.

MAIN RESULTS

In this small series of patients with H1N1/acute respiratory distress syndrome and hemodynamic compromise, therapeutic plasma exchange appeared to benefit as a method of mitigating the associated cytokine storm. The procedure was well tolerated with no reported side effects. All three patients survived, defying the predicted mortality. Because these procedures used the filtration exchange method, it was performed in a timely fashion by intensive care unit personnel and on equipment already available in the intensive care unit for renal support.

CONCLUSIONS

This very limited case series suggest there may be a role for therapeutic plasma exchange as a rescue therapy in severe shock and acute lung injury related to pH1N1 that has not responded to traditional therapy.

Continuous renal replacement therapies: a brief primer for the neurointensivist

Continuous renal replacement therapy (CRRT) is a renal replacement modality that is often used in the ICU setting, including the neuro-ICU. This form of renal replacement therapy has been used classically for acute renal failure in patients with hemodynamic compromise, but is gaining acceptance as a method to control vascular and extra-vascular volume and mediate cytokines in non-renal diseases. Although these uses are briefly discussed, this review concentrates on the different forms of continuous renal replacement, mainly focusing on the technology of convective versus diffusive modalities and briefly on filter technology. There is also discussion on the various anticoagulation regimes used in CRRT including data on performing CRRT without anticoagulation. This review is not meant to be a discussion on the pros and cons of CRRT versus intermittent dialysis, but rather a primer on the technology of CRRT and how this therapy may affect general care of the ICU patient.

Plasma exchange therapy for thrombotic microangiopathies

Thrombotic microangiopathies (TMAs) are syndromes associated with thrombocytopenia and multiple organ failure. Plasma exchange is a proven therapy for primary TMA such as thrombotic thrombocytopenic purpura (TTP). There is growing evidence that plasma exchange therapy might also facilitate resolution of organ dysfunction and improve outcomes for secondary TMAs such as disseminated intravascular coagulation (DIC) and systemic inflammation-induced TTP. In this review, we survey the current available evidence and practice of plasma exchange therapy for TMAs.

Continuous renal replacement therapy results in respiratory and hemodynamic beneficial effects in pediatric patients with severe systemic inflammatory response syndrome and multiorgan system dysfunction

BACKGROUND

Proinflammatory mediators have been implicated in the pathogenesis of systemic inflammatory response syndrome and multiorgan system dysfunction. These mediators are of molecular weights that render them amenable to clearance by the hemodiafiltration mode of continuous renal replacement therapy.

OBJECTIVE

To determine whether a period of 48 hrs of continuous renal replacement therapy in patients with multiorgan system dysfunction secondary to systemic inflammatory response syndrome improves their degree of anasarca as well as their cardiovascular and respiratory systems performances.

DATA SOURCE

Retrospective chart review.

STUDY DESIGN

Charts of patients diagnosed with systemic inflammatory response syndrome, who were mechanically ventilated in the pediatric intensive care unit and at the same time were receiving continuous renal replacement therapy, from 2004 to 2008, were reviewed. Patients with preexisting renal failure and/or received extracorporeal membrane oxygenation were excluded. Changes in the patients' body weights, oxygenation indices, and vasopressor scores were used as markers for responsiveness to continuous renal replacement therapy. DATA ANALYSIS AND MAIN RESULTS: Data from twenty-two patients with systemic inflammatory response syndrome and with three to five concomitantly diagnosed organ system dysfunctions, at the time continuous renal replacement therapy was initiated, were analyzed. None of the six patients who had five organ system dysfunctions survived to be discharged from the pediatric intensive care unit. Of the remaining 16 patients with three or four organ system dysfunctions, eight (50%) survived and eight (50%) died. The patients' weight, oxygenation indices, and vasopressor scores did not significantly change with 48 hrs of continuous renal replacement therapy.

CONCLUSIONS

Mechanically ventilated patients with systemic inflammatory response syndrome and multiorgan system dysfunction demonstrated a precarious and insignificant response to 48 hrs of continuous renal replacement therapy in a hemodiafiltration mode. However, the patients' overall clinical status did not deteriorate during this therapy. More prospective studies are necessary to determine the effectiveness of continuous renal replacement therapy in patients with multiorgan system dysfunction.

Early introduction of peritoneal dialysis may improve survival in severe sepsis

OBJECTIVES

Acute renal failure is a serious complication of sepsis and is associated with a very high mortality. Recent evidence suggests that proinflammatory cytokines (interleukins 1 and 6 and tumor necrosis factor alpha) released into the circulation in response to sepsis can be removed from the blood via hemofiltration and appear in the dialysate in times of peritoneal dialysis as well.

METHODS

An infant who developed acute renal failure in full-blown sepsis is presented. Peritoneal dialysis was initiated on the fourth day after admission. Changes in clinical and laboratory parameters were monitored.

RESULTS

Urine output (1.13 mL/kg per hour) began to improve on the sixth day after admission (second day after the introduction of peritoneal dialysis); normalization of serum creatinine level was achieved on the 30th day after admission. Parallel with the serum creatinine level (255 micromol/L on day 5 after admission vs 208 micromol/L by day 9 after admission, fifth day of PD), serum procalcitonin, C-reactive protein, and lactate dehydrogenase levels decreased dramatically (procalcitonin >500 vs 261 microg/L; C-reactive protein, 203 vs 25.9 mg/L; and lactate dehydrogenase, 3092 vs 1744 U/L on days 5 and 9 after admission, respectively).

CONCLUSIONS

Considering that there are no guidelines defined for the management of acute renal failure with accompanying sepsis in children, authors point out that peritoneal dialysis is an easy-to-perform and effective renal replacement modality in low body weight, critically ill patients. Early initiation of peritoneal dialysis does not only improve fluid and electrolyte imbalance but also may significantly reduce the destructive effect of systemic cytokine storm in sepsis and contribute to a more favorable outcome, even in cases of critical cardiovascular and hemostaseological status.

Clinical practice parameters for hemodynamic support of pediatric and neonatal septic shock: 2007 update from the American College of Critical Care Medicine

BACKGROUND

The Institute of Medicine calls for the use of clinical guidelines and practice parameters to promote "best practices" and to improve patient outcomes.

OBJECTIVE

2007 update of the 2002 American College of Critical Care Medicine Clinical Guidelines for Hemodynamic Support of Neonates and Children with Septic Shock.

PARTICIPANTS

Society of Critical Care Medicine members with special interest in neonatal and pediatric septic shock were identified from general solicitation at the Society of Critical Care Medicine Educational and Scientific Symposia (2001-2006).

METHODS

The Pubmed/MEDLINE literature database (1966-2006) was searched using the keywords and phrases: sepsis, septicemia, septic shock, endotoxemia, persistent pulmonary hypertension, nitric oxide, extracorporeal membrane oxygenation (ECMO), and American College of Critical Care Medicine guidelines. Best practice centers that reported best outcomes were identified and their practices examined as models of care. Using a modified Delphi method, 30 experts graded new literature. Over 30 additional experts then reviewed the updated recommendations. The document was subsequently modified until there was greater than 90% expert consensus.

RESULTS

The 2002 guidelines were widely disseminated, translated into Spanish and Portuguese, and incorporated into Society of Critical Care Medicine and AHA sanctioned recommendations. Centers that implemented the 2002 guidelines reported best practice outcomes (hospital mortality 1%-3% in previously healthy, and 7%-10% in chronically ill children). Early use of 2002 guidelines was associated with improved outcome in the community hospital emergency department (number needed to treat = 3.3) and tertiary pediatric intensive care setting (number needed to treat = 3.6); every hour that went by without guideline adherence was associated with a 1.4-fold increased mortality risk. The updated 2007 guidelines continue to recognize an increased likelihood that children with septic shock, compared with adults, require 1) proportionally larger quantities of fluid, 2) inotrope and vasodilator therapies, 3) hydrocortisone for absolute adrenal insufficiency, and 4) ECMO for refractory shock. The major new recommendation in the 2007 update is earlier use of inotrope support through peripheral access until central access is attained.

CONCLUSION

The 2007 update continues to emphasize early use of age-specific therapies to attain time-sensitive goals, specifically recommending 1) first hour fluid resuscitation and inotrope therapy directed to goals of threshold heart rates, normal blood pressure, and capillary refill 70% and cardiac index 3.3-6.0 L/min/m.

[ECMO: experience in paediatrics]

INTRODUCTION

ECMO (Extracorporeal Membrane Oxygenation) provides a vital support to patients with supposed reversible respiratory and/or cardiac failure, in whom conventional support techniques have been previously unsuccessful.

OBJECTIVES

To determinate the criteria used in our hospital to put paediatric patients on ECMO, compare their clinical course depending on their pathology (respiratory failure, congenital heart disease or sepsis) and identify the sequelae attributable to this technique.

MATERIAL AND METHOD

A retrospective review of clinical records of all patients on ECMO support in our centre, excluding those presenting typically in neonatal period.

RESULTS

ECMO was used on 16 patients from June 2001 to January 2007, of which 50% were males. The median age was 7 months (from 21 days to 11 years). The reason for starting ECMO was respiratory failure in 11 cases (oxygenation index >40 and/or alveolar-arterial oxygen gradient >605), congenital heart disease in 2 and sepsis in 3 (due to shock unresponsive to adequate resuscitation). The median time to starting ECMO from PICU admission was 3.58 days (from 12h to 9 days). Venovenous cannulation was used initially in 8 patients, but 5 of them needed venoarterial ECMO later. The technique was used for a mean of 8 days (from 1 to 28 days). The main complication was the isolation of bacteria in different cultures (8 patients). The overall survival was 50% (6 patients with respiratory failure and both patients submitted to cardiac surgery). Extracorporeal support was withdrawn in 7 children because their clinical situation was irreversible. Another patient died seven days after successful decannulation. We have not found any serious sequel among survivors that could be attributable to this technique.

CONCLUSIONS

Survival among children supported with ECMO in our hospital is similar to that recorded by the ELSO in 2004, although the prognosis depends on the initial pathology. There are different criteria for starting this technique depending on the underlying diseases: respiratory index of poor prognosis in patients with respiratory failure, haemodynamic instability in those with sepsis or cardiac failure after cardiovascular surgery. We have not found any serious sequel among the survivors which could be attributable to this technique.

Pediatric critical care management of septic shock prior to acute kidney injury and renal replacement therapy

A high index of suspicion for bacterial sepsis and recognition of the potential for rapid deterioration is essential for impacting patient outcome. Meningococcemia produces a stereotypical clinical and biochemical constellation of profound septic shock and purpura fulminans with marked inflammatory disturbance and a complex disruption of coagulation. Meningococcal infections preferentially affect infants and young children, but adolescents are also at risk. Aggressive fluid resuscitation, hemodynamic management, and clinical monitoring are based on understanding of pathophysiologic disturbances typical of the pediatric cardiovascular response and guided by evidence-based guidelines. Appropriate antibiotic choice is important, and corticosteroid use may be beneficial. A variety of efforts to manipulate the coagulation abnormalities may be considered, although evidence is lacking. Extracorporeal support remains a consideration both for the failing cardiorespiratory systems but also potentially for the use of plasma exchange. A team approach between the intensivist and subspecialist is important in managing the frequent multiorgan complications seen with meningococcemia.

Renal replacement therapy in the critical care unit

Acute renal failure is common in critically ill patients. Many intensive care unit patients require renal replacement therapy (RRT). Hemodialysis can be performed as intermittent treatments or as continuous RRT, which can be customized to clinical goals by the use of carefully designed replacement fluids and hemodialysates. The available forms of RRT are reviewed, with emphasis on the clinical indications that contribute to the choice and design of therapy. Practical issues and troubleshooting are discussed, as are available options for anticoagulation during RRT. Consideration is given to modality choice, hemodynamic issues, costs, and physiologic outcomes.

Multiple organ system extracorporeal support in critically ill children

Multiple organ system extracorporeal support effectively supports brain, heart, lung, liver, kidney, coagulation, red blood cell, and immune cell function in the sickest infants and children who have multiple organ system failure. These therapies have optimum benefit if: (1) the underlying disease is reversible; (2) the therapies are performed expertly and are monitored to prevent and minimize systemic hemolysis; and (3) the therapies are provided in a goal-directed manner. These therapies represent a significant advance in pediatric critical care medicine. This article provides a framework for this multidisciplinary team approach for implementing these therapies.

Sepsis and septic shock: progress and future considerations

OBJECTIVE

To define sepsis and septic shock in children, to outline an approach to treatment in the emergency, critical care units and to outline a global sepsis initiative.

METHODS

A synopsis of the literature and adaptation of current treatment guidelines for sepsis in children.

RESULTS

Sepsis in children can be recognized early using clinical parameters. Prompt, aggressive treatment using ACCM guidelines has resulted in improved outcomes.

CONCLUSION

A collaborative approach to the diagnosis and treatment of sepsis by the Emergency Department and Pediatric Intensive Care Unit can lead to improved outcomes of children with sepsis. Treatment based on a model of escalating levels of care and organ support which takes into consideration the resources available in different settings is likely to improve sepsis outcomes globally. The World Federation Sepsis Initiative (www.wfpiccs.org) is intended to promote treatment based on this model.

Effect of plasmapheresis on the immune system in endotoxin-induced sepsis

BACKGROUND

It has been proposed that plasmapheresis is most effective when applied early in Gram-negative sepsis. We therefore studied the effect of early plasmapheresis on immunity in experimental Escherichia coli endotoxin-induced sepsis.

METHODS

20 pigs received 30 microg/kg of E. coli endotoxin. 40 min later, half of the pigs were treated with plasmapheresis which lasted 4 h. The adhesion molecules, the oxidative burst, the number of neutrophils in blood and lungs, and cytokines were measured.

RESULTS

Infusion of endotoxin was associated with activation of adhesion molecules increased oxidative burst, increased concentration of cytokine, and accumulation of granulocytes in lung tissue. Plasmapheresis reduced the oxidative burst, and there was a tendency towards a reduced accumulation of granulocytes in the lung.

CONCLUSION

Though plasmapheresis was initiated early after the endotoxin infusion, it only temporarily attenuated a part of the activated cell-mediated immunity.

Polymyxin B-immobilized fiber hemoperfusion with the PMX-05R column in elderly patients suffering from septic shock

BACKGROUND

Direct hemoperfusion with the polymyxin B-immobilized fiber (PMX-20R) column has a positive effect on outcome in patients with sepsis or septic shock. The PMX-05R column has a low priming volume and has been used in pediatric patients with septic shock. The aim of the present study was to determine whether PMX-F treatment with the PMX-05R column is effective in elderly patients with septic shock.

PATIENTS AND METHODS

We performed direct hemoperfusion twice with the PMX-05R column in 8 septic shock patients who were over 80 years of age. Five of the 8 patients survived. The 3 patients who died were undergoing hemodialysis for chronic renal failure, and methicillin-resistant Staphylococcus aureus was detected in all 3.

RESULTS

PMX-F treatment significantly increased systolic and diastolic blood pressures (P = 0.0004 for both) and significantly reduced heart rate (P < 0.0001), the blood endotoxin level (P = 0.0011), blood IL-6 level (P = 0.039), C-reactive protein level (P < 0.0001), and white blood cell count (P < 0.0001).

CONCLUSIONS

Direct hemoperfusion with the PMX-05R column is effective in ameliorating clinical and laboratory abnormalities in elderly septic shock patients.