Pathogens and outcomes in pediatric septic shock patients supported by extracorporeal membrane oxygenation

The International Society for Heart and Lung Transplantation (ISHLT): 2024 infection definitions for durable and acute mechanical circulatory support devices

Infections remain a significant concern in patients receiving mechanical circulatory support (MCS), encompassing both durable and acute devices. This consensus manuscript provides updated definitions for infections associated with durable MCS devices and new definitions for infections in acute MCS, integrating a comprehensive review of existing literature and collaborative discussions among multidisciplinary specialists. By establishing consensus definitions, we seek to enhance clinical care, facilitate consistent reporting in research studies, and ultimately improve outcomes for patients receiving MCS.

Outcomes of Pediatric Patients with Sepsis Managed on Extracorporeal Membrane Oxygenation: An Analysis of the Extracorporeal Life Support Organization Registry

Extracorporeal membrane oxygenation (ECMO) support is increasingly used for refractory septic shock. There is a lack of data on the outcomes of children requiring ECMO support for refractory septic shock. Our study objective was to describe the variables associated with survival, risk factors for mortality, and outcomes of children requiring ECMO support for refractory shock. This was retrospective registry study of 340 international centers contributing data to the ELSO Registry, analyzing children <18 years who received ECMO with septic shock, severe sepsis, sepsis, systemic inflammatory response syndrome, toxic shock syndrome, shock associated with infection, and septicemia from any organism from 1990 to 2015. Outcomes were analyzed by categorizing the data into survivors and nonsurvivors. Logistic regression models were used to describe the association of dependent variable and multiple independent variables. A total of 1,928 patients were identified who met the inclusion criteria. In total, 744 (38.5%) of the cohort survived. Survivors in this cohort tend to have a longer duration of ECMO (230 vs. 201 hours, p = 0.005) and shorter time from intubation to ECMO cannulation (87 vs. 116 hours, p = 0.0033) when compared to nonsurvivors. Survivors were also noted to have higher pH, higher serum bicarbonate, higher saturations, and higher systolic, diastolic, and mean arterial pressures compared to nonsurvivors. These results suggest that early initiation of ECMO therapy for refractory sepsis is associated with better patient outcomes. ECMO is unlikely to recover patients once circulatory and metabolic collapse has developed.

Comparison of the predictive ability of lactate and central venous blood gas in pediatric venoarterial mode extracorporeal membrane oxygenation outcome

BACKGROUND

This study aims to compare lactate and central venous blood gas in the prediction of outcome in pediatric venoarterial mode extracorporeal membrane oxygenation (V-A ECMO).

METHOD

This was a retrospective observational study conducted on patients undergoing V-A ECMO care in the pediatric intensive care unit of a tertiary medical center in Taiwan. Patients under 18 years of age undergoing V-A ECMO from January 2009 to April 2019 were included in this study.

RESULTS

This study consisted of 47 children who received V-A ECMO with an overall weaning rate of 66.0%. The mean age was 5.5 years and mean ECMO duration was 11.6 days. Successful weaning group had significantly lower lactate levels at initial (58.7 ± 47.0 mg/dL vs. 108.0 ± 55.3 mg/dL, p = 0.003), 0-12 h (37.8 ± 29.0 mg/dL vs. 83.5 ± 60.0 mg/dL, p Z 0.001), and 12-24 h (29.4 ± 26.9 mg/dL vs. 69.1 ± 59.1 mg/dL, p = 0.003) after ECMO initiation; however, the central venous blood gas including pH, HCO₃, CO₂, base excess (BE), and O₂ saturation showed no significant difference. The favorable outcome group had significantly lower lactate levels at 0-12 h (32.8 ± 26.3 mg/dL vs. 71.3 ± 53.3 mg/dL, p = 0.005), and 12-24 h (20.7 ± 10.2 mg/dL vs. 61.9 ± 53.5 mg/dL, p = 0.002); however, the HCO₃ levels (26.2 ± 4.5 mmol/L vs. 22.9 ± 6.8 mmol/L, p = 0.042) and BE (2.2 ± 5.4 vs. 2.2 ± 8.5, p = 0.047) were significantly higher at 12-24 h. In multivariate logistic regression, 12-24 h lactate value was an independent factor for unfavorable outcomes (p = 0.015, odds ratio [OR] = 1.1) with the best cut-off value of 48.6 mg/dL (sensitivity 48%, specificity 100%).

CONCLUSION

Lactate has better outcome prediction than central venous blood gas in pediatric V-A ECMO. The lactate value 12-24 h after ECMO initiation was an independent factor for unfavorable outcomes.

Role of Extracorporeal Membrane Oxygenation in Adults and Children With Refractory Septic Shock: A Systematic Review and Meta-Analysis

BACKGROUND

The benefits of extracorporeal membrane oxygenation in patients with refractory septic shock remain controversial. Current guidelines on the management of refractory septic shock recommend the consideration of extracorporeal membrane oxygenation as a salvage therapy. The difference between adults and children with septic refractory shock treated with extracorporeal membrane oxygenation has not been previously analyzed. We aimed to review peer-reviewed publications on the role of extracorporeal membrane oxygenation in adults and children with refractory septic shock.

METHODS

Studies reporting on mortality in both adults and children with refractory septic shock supported with extracorporeal membrane oxygenation published in PubMed, Cochrane Library, and Embase databases were included in the meta-analysis. Study eligibility was independently assessed by two authors, and disagreements were resolved by a third author. The outcome measure was survival at discharge. Subgroup analysis included the adult and pediatric groups.

RESULTS

Of the 293 articles screened, 14 original articles were identified for systematic review and meta-analysis. The cumulative estimate of survival (14 studies, 535 patients) in the cohort was 39% (95% confidence interval [CI]: 27-51%). During the subgroup analysis, the cumulative estimate of survival at discharge in the adult group (6 studies, 276 patients) in the cohort was 18% (95% CI: 10-27%), and that in the pediatric group (8 studies, 259 patients) was 53% (95% CI: 47-59%).

CONCLUSIONS

The survival rate of adults with refractory septic shock requiring extracorporeal membrane oxygenation was 18%, and children with refractory septic shock requiring extracorporeal membrane oxygenation had a higher survival rate (53%) than adults.

Risk Factors for Mortality in Refractory Pediatric Septic Shock Supported with Extracorporeal Life Support

Risk factors for mortality in children with refractory pediatric septic shock who are supported with extracorporeal life support (ECLS) are largely unknown. Therefore, we performed univariable and multivariable analyses to determine risk factors for mortality among children (<19 years) who underwent an ECLS run between January 2012 and September 2014 at eight tertiary pediatric hospitals, and who had septic shock based on 2005 International Consensus Criteria. Of the 514 children treated with ECLS during the study period, 70 were identified with septic shock. The mortality rate was similar between those with (54.3%) and without septic shock (43.7%). Among those with septic shock, significant risk factors for mortality included cardiac failure or extracorporeal cardiopulmonary resuscitation (ECPR) as indication for ECLS cannulation compared with respiratory failure (P = 0.003), having a new neurologic event following cannulation (P = 0.032), acquiring a new infection following cannulation (P = 0.005), inability to normalize pH in the 48 hours following ECLS cannulation (P = 0.010), and requiring higher daily volume of platelet transfusions (P = 0.005). These findings can be used to help guide clinical decision making for children with septic shock that is refractory to medical management.

Role of extracorporeal membrane oxygenation in children with sepsis: a systematic review and meta-analysis

BACKGROUND

The benefits of extracorporeal membrane oxygenation (ECMO) in children with sepsis remain controversial. Current guidelines on management of septic shock in children recommend consideration of ECMO as salvage therapy. We sought to review peer-reviewed publications on effectiveness of ECMO in children with sepsis.

METHODS

Studies reporting on mortality in children with sepsis supported with ECMO, published in PubMed, Scopus and Embase from 1972 till February 2020, were included in the review. This study was done in adherence to Preferred Reporting Items for Systematic Review and Meta-Analysis statement after registering the review protocol with PROSPERO. Study eligibility was independently assessed by two authors and disagreements resolved by a third author. Publications were reviewed for quality using Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Random-effects meta-analyses (DerSimonian and Laird) were conducted, and 95% confidence intervals were computed using the Clopper-Pearson method. Outliers were identified by the Baujat plot and leave-one-out analysis if there was considerable heterogeneity. The primary outcome measure was survival to discharge. Secondary outcome measures included hospital length of stay, subgroup analysis of neonatal and paediatric groups, types and duration of ECMO and complications .

RESULTS

Of the 2054 articles screened, we identified 23 original articles for systematic review and meta-analysis. Cumulative estimate of survival (13 studies, 2559 patients) in the cohort was 59% (95%CI: 51-67%). Patients had a median length of hospital stay of 28.8 days, median intensive care unit stay of 13.5 days, and median ECMO duration of 129 h. Children needing venoarterial ECMO (9 studies, 208 patients) showed overall pooled survival of 65% (95%CI: 50-80%). Neonates (< 4 weeks of age) with sepsis needing ECMO (7 studies, 85 neonates) had pooled survival of 73% (95%CI: 56- 87%). Gram positive organisms were the most common pathogens (47%) in septic children supported with ECMO.

CONCLUSION

Survival rates of children with sepsis needing ECMO was 59%. Neonates had higher survival rates (73%); gram positive organisms accounted for most common infections in children needing ECMO. Despite limitations, pooled survival data from this review indicates consideration of ECMO in refractory septic shock for all pediatric age groups.

Diagnostic accuracy of time to first positivity of blood cultures for predicting severe clinical outcomes in children with pneumonia-related bacteremia

Early recognition of severe clinical outcomes in children with pneumonia-related bacteremia is vitally important because of the high mortality. This study aims to explore risk factors for severe clinical outcomes in children with pneumonia-related bacteremia and evaluate the value of time to first positive blood cultures (TTFP) in predicting prognosis. Children with pneumonia-related bacteremia in Children’s Hospital of Chongqing Medical University were included (January 2013–May 2019), respectively. TTFP and clinical parameters were collected and analyzed. The area under the curve (AUC)-receiver operating characteristic was used to evaluate the discrimination ability of TTFP. Multivariate logistic regression tests were performed to evaluate the association between TTFP and severe clinical outcomes. A total of 242 children with pneumonia-related bacteremia were included. The least absolute shrinkage and selection operator (LASSO) regression analysis identified TTFP, serum albumin (ALB) and lactic dehydrogenase (LDH) as predictors of in-hospital mortality. Multivariate logistic regression analysis showed that shorter TTFP (OR 0.94; 95% CI 0.89 to 0.97; p<0.01), lower ALB level (OR 0.93; 95% CI 0.89 to 0.98; p<0.01) and higher LDH level (OR 1.001; 95% CI 1.000 to 1.001; p<0.01) were risk factors for in-hospital mortality in children with pneumonia-related bacteremia. AUC of TTFP for predicting in-hospital mortality was 0.748 (95% CI 0.668 to 0.829). Shorter TTFP (≤16 hours) was associated with in-hospital mortality and septic shock. TTFP plays an important role in predicting severe clinical outcomes in children with pneumonia-related bacteremia.

Extra-Corporeal Membrane Oxygenation for Neonatal Respiratory Support

To review our experience with Extra-Corporeal Membrane Oxygenation (ECMO) for respiratory support in neonates. From 1989 to 2018 2114 patients underwent respiratory ECMO support, with 764 (36%) neonates. Veno-Venous (V-V) cannulation was used in 428 (56%) neonates and Veno-Arterial (V-A) in 336 (44%). Historically V-V ECMO was our preferred modality, but due to lack of suitable cannula in the last 7 years V-A was used in 209/228 (92%) neonates. Mean and inter-quartile range of ECMO duration was 117 hours (inter-quartile range 90 to 164 hours). Overall 724 (95%) neonates survived to ECMO decannulation, with 640 (84%) hospital discharge. Survival varied with underlying diagnosis: meconium aspiration 98% (354/362), persistent pulmonary hypertension 80% (120/151), congenital diaphragmatic hernia 66% (82/124), sepsis 59% (35/59), pneumonia 86% (6/7), other 71% (43/61). Survival was 86% with V-V and 80% with V-A cannulation, better than ELSO Registry with 77% V-V and 63% V-A. Major complications: cerebral infarction/hemorrhage in 4.7% (31.1% survival to discharge), renal replacement therapy in 17.6% (58.1% survival to discharge), new infection in 2.9%, with negative impact on survival (30%). Following a circuit design modification and subsequent reduction in heparin requirement, intracerebral hemorrhage decreased to 9/299 (3.0%) radiologically proven cerebral infarction/hemorrhage. We concluded (1) outcomes from neonatal ECMO in our large case series were excellent, with better survival and lower complication rate than reported in ELSO registry. (2) These results highlight the benefits of ECMO service in high volume units. (3) The similar survival rate seen in neonates with V-A and V-V cannulation differs from the ELSO register; this may reflect the change in cannulation enforced by lack of suitable V-V cannula and all neonates undergoing V-A cannulation.

Applicability of an in-house saponin-based extraction method in Bruker Biotyper matrix-assisted laser desorption/ionization time-of-flight mass spectrometry system for identifying bacterial and fungal species in positively flagged pediatric VersaTREK blood cultures

BACKGROUND/PURPOSE

Early identification of pathogens causing bloodstream infection (BSI) is critical for prompt administration of appropriate antimicrobial therapy.

METHODS

We used an in-house saponin-based extraction method to evaluate the performance of Bruker Biotyper MALDI-TOF MS system (MALDI Biotyper) for bacterial and fungal identification in 2013 positively-flagged VersaTREK blood culture bottles.

RESULTS

A total of 180 monomicrobial and 23 polymicrobial positive blood cultures were investigated. Among monomicrobial positive blood cultures, the MALDI Biotyper recognized 90.6% and 81.7% of organisms directly from the flagged blood culture bottles to the genus and species levels, respectively. The MALDI Biotyper also correctly characterized one of the polymicrobial organisms to the species level in 20 (87%) bottles and to the genus level in 21 (91.3%) bottles. The overall identification rate using our protocol was 90.6% (184/203) and 82.3% (167/203) for genus and species levels, respectively. Identification accuracy was higher for Gram-positive than Gram-negative organisms and was the lowest for yeasts. Score values of identification were ≥1.500 for 200 (98.5%) bottles, ≥1.700 for 195 (96.1%) bottles and ≥2.000 for 182 (89.7%) bottles. Moreover, 83.5% and 92% of the isolates were identified precisely to species and genus level with the lower cutoff score of 1.500. Using our protocol also helped identifying BSI pathogens 18-24 h earlier compared to the sub-cultured colonies.

CONCLUSION

Using Bruker MALDI Biotyper for identification of isolates directly from positive VersaTREK blood culture bottles, our in-house saponin-based protocol provided a more rapid turn-around time for correct identification of BSI pathogens than the conventional methods.

ECMO for Neonatal Sepsis in 2019

Sepsis and septic shock in newborns causes mortality and morbidity depending on the organism and primary site. ECMO provides cardiorespiratory support to allow adequate organ perfusion during the time for antibiotics and source control surgery (if needed) to occur. ECMO mode and cannulation site vary depending on support required and local preference. Earlier and more aggressive use of ECMO can improve survival.

Effects of influenza vaccine and sun exposure time against laboratory-confirmed influenza hospitalizations among young children during the 2012-13 to 2015-16 influenza seasons

BACKGROUND

Influenza is a major cause of acute respiratory infection burden worldwide, leading to many hospitalizations. An annual influenza vaccine is believed to be the best way to prevent influenza-related illnesses. We focused on the efficacies of other possible preventive measures such as increasing sun exposure time and dietary supplements to prevent these illnesses.

METHODS

We conducted a matched-pair case-control study along with the Taiwan Pediatric Infectious Disease Alliance. We included influenza-related hospitalized patients with age ranging from 6 months to 5 years during the 2012-2013, 2013-2014, 2014-2015, and 2015-2016 influenza seasons. The controls were comparable to cases in age, sex, and residential area and had no influenza-related hospitalization records in the same season. We extracted data from vaccination histories and got the patients' guardians to complete questionnaires. Data were analyzed using conditional logistic regression.

RESULTS

We enrolled 1514 children (421 influenza-infected cases and 1093 controls) in the study. We found seasonal influenza vaccination to be an independent protective factor against hospitalizations owing to influenza [p < 0.01; odds ratio (OR), 0.427; 95% confidence interval (CI), 0.306-0.594]. Children with mean sun exposure time of >7 h/week had a significantly lower risk of influenza-related hospitalizations than those with the mean sun exposure time of ≤7 h/week (p < 0.05; OR, 0.667; 95% CI, 0.491-0.906).

CONCLUSIONS

Seasonal influenza vaccination effectively prevents influenza-related hospitalizations in children aged ≤5 years. Besides, >7 h of sun exposure/week may also be associated with lower risk of influenza-related hospitalizations in children.

Risk factors for refractory septic shock treated with VA ECMO

Background

Refractory septic shock is a serious disorder with high mortality. There is currently limited evidence to support the use of extracorporeal membrane oxygenation (ECMO) in adult septic shock. We describe the outcome of patients with refractory septic shock in our hospital and try to identify prognostic factors.

Methods

We studied a total of 23 (14 males and 9 females) refractory septic shock patients treated with venoarterial (VA) ECMO in our hospital. Clinical parameters of survival and death groups, laboratory parameters before and after ECMO placement were analyzed.

Results

Eight patients were successfully weaned off ECMO and five patients were discharged. The sepsis-related organ failure assessment (SOFA) score and shock-to-ECMO interval before ECMO placement in the survival group were significantly lower than those in the death group (12.0 vs. 15.0, P=0.007; 23.5 vs. 42.2 h, P=0.037). The number of cases who had the normal range of ScvO₂% between the survival group and the death group at 12 h (4 vs. 4, P=0.033), 18 h (5 vs. 7, P=0.016) and 24 h (5 vs. 9, P=0.043) during ECMO was significantly different. In univariate logistic regression analysis, the case of patients with normal central venous oxygen saturation (ScvO₂) % at 12 h during ECMO [odds ratio (OR) 14.0, 95% confidence interval (CI): 1.200-163.367, P=0.035] was significantly associated with risk of the prognosis of patients.

Conclusions

In adult refractory septic shock patients, ScvO₂% at 12 h during ECMO may be a risk factor for patient prognosis.

Use of extracorporeal membrane oxygenation and associated outcomes in children hospitalized for sepsis in the United States: A large population-based study

Objective

The American College of Critical Care Medicine recommends that children with persistent fluid, catecholamine, and hormone-resistant septic shock be considered for extracorporeal membrane oxygenation (ECMO) support. Current national estimates of ECMO use in hospitalized children with sepsis are unknown. We sought to examine the use of ECMO in these children and to examine the overall outcomes such as in-hospital mortality, length of stay (LOS), and hospitalization charges (HC).

Methods

A retrospective analysis of the National Inpatient Sample, which approximates a 20% stratified sample of all discharges from United States community hospitals, was performed. All children (≤ 17 years) who were hospitalized for sepsis between 2012 and 2014 were included. The associations between ECMO and outcomes were examined by multivariable linear and logistic regression models.

Results

A total of 62,310 children were included in the study. The mean age was 4.2 years. ECMO was provided to 415 of the children (0.67% of the cohort with sepsis). Comparative outcomes of sepsis in children who received ECMO versus those who did not included in-hospital mortality rate (41% vs 2.8%), mean HC ($749,370 vs $90,568) and mean LOS (28.8 vs 9.1 days). After adjusting for confounding factors, children receiving ECMO had higher odds of mortality (OR 11.15, 95% CI 6.57–18.92, p < 0.001), longer LOS (6.6 days longer, p = 0.0004), and higher HC ($510,523 higher, p < 0.0001).

Conclusions

Use of ECMO in children with sepsis is associated with considerable resource utilization but has 59% survival to discharge. Further studies are needed to examine the post discharge and neurocognitive outcomes in survivors.

Contribution of Malaria to Inhospital Mortality in Papua New Guinean Children from a Malaria-Endemic Area: A Prospective Observational Study

We aimed to identify clinical and laboratory predictors of mortality in children from a malaria-endemic area of Papua New Guinea hospitalized for severe illness. Children aged 0.5-10 years presenting with any WHO-defined feature of severe malarial illness were eligible for recruitment. Each child was assessed with a detailed clinical examination, blood film microscopy, malaria rapid diagnostic testing (RDT), a full blood examination, and blood glucose and lactate concentrations. Clinical care was coordinated by local medical staff in accordance with national guidelines. Daily study assessments were conducted until death or discharge. Other biochemical tests and malaria polymerase chain reaction (PCR) tests were performed subsequently. Logistic regression identified independent predictors of death. Of 787 evaluable children with severe illness, 336 had confirmed severe malaria (microscopy and PCR positive) and 58 (6.6%) died during hospitalization. The independent predictors of mortality were hyperlactatemia (adjusted odds ratio [95% CI]: 2.85 [1.24-6.41], P = 0.01), malnutrition (2.92 [1.36-6.23], P = 0.005), renal impairment (3.85 [1.53-9.24], P = 0.002), plasma albumin (0.93 [0.88-0.98] for a 1 g/L increase, P = 0.004), and Blantyre coma score (BCS) ≤ 2 (10.3 [4.77-23.0] versus a normal BCS, P < 0.0001). Confirmed severe malaria (0.11 [0.03-0.30] versus non-malarial severe illness, P < 0.0001) was independently associated with lower mortality. Although established risk factors were evident, malaria was inversely associated with mortality. This highlights the importance of accurate diagnosis through blood film microscopy, RDTs, and, if available, PCR to both guide management and provide valid epidemiological data.

Adenovirus replication and host innate response in primary human airway epithelial cells

BACKGROUND

Adenovirus infections are very common in children and sometimes fatal. Immune responses and hypercytokinemia are related to disease severity in patients with adenovirus infection. Understanding of viral replication and immune responses could help elucidate the immunopathogenesis of severe adenovirus infections.

METHODS

Polarized human airway epithelial cells (hAECs) were set up to mimic human airway, and we conducted high (1 the multiplicity of infection, MOI) and low dosage (0.5 MOI) of wild-type adenovirus serotype 3 infection in hAECs from both apical (AP) and basolateral (BL) compartments, compared the viral replication kinetics and measured 25 cytokine and 9 chemokine levels by multiplex immunoassay to evaluate the host immune response.

RESULTS

Virus titer was the highest in the apical compartment in low dose apical infection. BL infection showed a relative steady viral titer in different doses and infection sites. Responses of several cytokines such as IL-1RA, IL-21 and all of the chemokines were found after adenovirus infection. Besides, the responses detected in the BL compartment were generally higher than those in the apical compartment, especially IL-1RA, IL-21, GM-CSF, GRO-α, SDF-1α and IL-8.

CONCLUSION

During the infections of hAECs by adenovirus, higher viral replication was found in the apical compartment but cytokine and chemokine responses were higher in the basolateral compartment. This indicated viral entrance and replication occurred more in the apical part and major innate response took place in the basolateral part, which may make adenovirus infect human airway efficiently and cause different degree of severity.