Post-PICU Cognitive and Psychological Outcomes in Children Receiving Treatments for Acute Lymphoblastic Leukemia.

OBJECTIVES: To examine neurocognitive and psychological outcomes associated with post-PICU admissions in children treated for childhood acute lymphoblastic leukemia (ALL). DESIGN: Observational study from October 2007 to March 2017. SETTING: Pediatric onco-critical care unit. PATIENTS: All patients in this study (n = 296; ages 3-21) were treated for ALL on the St. Jude Total Therapy 16 clinical trial (NCT00549848) from 2007 to 2017. Of these, 104 patients were admitted to the PICU during protocol-directed therapy. All patients completed protocol-directed neurocognitive monitoring prospectively, at the end of cancer-directed therapy. Data on PICU stays were abstracted retrospectively from the medical record. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Demographic and critical illness variables were abstracted from institutional databases and medical records. Neurocognitive and psychosocial outcomes were prospectively obtained at the end of treatment. Children who had a PICU admission experienced significantly lower functioning compared to normative samples in several areas of cognitive functioning (working memory, processing speed, executive functions, inattention, math achievement, fine motor dexterity, and speed), daily living skills, and internalizing problems (all ps < 0.05). Compared with those without PICU admissions, patients with PICU admissions had worse performance on a measure of sustained attention (p = 0.017). The frequency of patients at risk for problems with learning and memory was significantly higher in the PICU group compared with the non-PICU group (25% vs 12%, p = 0.006). Critical illness symptom severity was not associated with neurocognitive or psychological outcomes. CONCLUSIONS: Children with ALL, with or without a PICU admission, experienced lower cognitive and psychological outcomes following treatment. Future research is needed to continue identifying risk factors for post-intensive care syndrome (PICS-p) and post-PICU cognitive and psychological impairments in pediatric patients.

Mortality Risk Factors in Pediatric Onco-Critical Care Patients and Machine Learning Derived Early Onco-Critical Care Phenotypes in a Retrospective Cohort.

OBJECTIVES: To use supervised and unsupervised statistical methodology to determine risk factors associated with mortality in critically ill pediatric oncology patients to identify patient phenotypes of interest for future prospective study. DESIGN: This retrospective cohort study included nonsurgical pediatric critical care admissions from January 2017 to December 2018. We determined the prevalence of multiple organ failure (MOF), ICU mortality, and associated factors. Consensus k-means clustering analysis was performed using 35 bedside admission variables for early, onco-critical care phenotype development. SETTING: Single critical care unit in a subspeciality pediatric hospital. INTERVENTION: None. PATIENTS: There were 364 critical care admissions in 324 patients with underlying malignancy, hematopoietic cell transplant, or immunodeficiency reviewed. MEASUREMENTS: Prevalence of multiple organ failure, ICU mortality, determination of early onco-critical care phenotypes. MAIN RESULTS: ICU mortality was 5.2% and was increased in those with MOF (18.4% MOF, 1.7% single organ failure [SOF], 0.6% no organ failure; p ≤ 0.0001). Prevalence of MOF was 23.9%. Significantly increased ICU mortality risk was associated with day 1 MOF (hazards ratio [HR] 2.27; 95% CI, 1.10-6.82; p = 0.03), MOF during ICU admission (HR 4.16; 95% CI, 1.09-15.86; p = 0.037), and with invasive mechanical ventilation requirement (IMV; HR 5.12; 95% CI, 1.31-19.94; p = 0.018). Four phenotypes were derived (PedOnc1-4). PedOnc1 and 2 represented patient groups with low mortality and SOF. PedOnc3 was enriched in patients with sepsis and MOF with mortality associated with liver and renal dysfunction. PedOnc4 had the highest frequency of ICU mortality and MOF characterized by acute respiratory failure requiring invasive mechanical ventilation at admission with neurologic dysfunction and/or severe sepsis. Notably, most of the mortality in PedOnc4 was early (i.e., within 72 hr of ICU admission). CONCLUSIONS: Mortality was lower than previously reported in critically ill pediatric oncology patients and was associated with MOF and IMV. These findings were further validated and expanded by the four derived nonsynonymous computable phenotypes. Of particular interest for future prospective validation and correlative biological study was the PedOnc4 phenotype, which was composed of patients with hypoxic respiratory failure requiring IMV with sepsis and/or neurologic dysfunction at ICU admission.

Beginning Restorative Activities Very Early: Implementation of an Early Mobility Initiative in a Pediatric Onco-Critical Care Unit.

INTRODUCTION: Children with underlying oncologic and hematologic diseases who require critical care services have unique risk factors for developing functional impairments from pediatric post-intensive care syndrome (PICS-p). Early mobilization and rehabilitation programs offer a promising approach for mitigating the effects of PICS-p in oncology patients but have not yet been studied in this high-risk population. METHODS: We describe the development and feasibility of implementing an early mobility quality improvement initiative in a dedicated pediatric onco-critical care unit. Our primary outcomes include the percentage of patients with consults for rehabilitation services within 72 h of admission, the percentage of patients who are mobilized within 72 h of admission, and the percentage of patients with a positive delirium screen after 48 h of admission. RESULTS: Between January 2019 and June 2020, we significantly increased the proportion of patients with consults ordered for rehabilitation services within 72 h of admission from 25 to 56% (p<0.001), increased the percentage of patients who were mobilized within 72 h of admission to the intensive care unit from 21 to 30% (p=0.02), and observed a decrease in patients with positive delirium screens from 43 to 37% (p=0.46). The early mobility initiative was not associated with an increase in unplanned extubations, unintentional removal of central venous catheters, or injury to patient or staff. CONCLUSIONS: Our experience supports the safety and feasibility of early mobility initiatives in pediatric onco-critical care. Additional evaluation is needed to determine the effects of early mobilization on patient outcomes.

Continuous Renal Replacement Therapy: A Review of Use and Application in Pediatric Hematopoietic Stem Cell Transplant Recipients.

Hematopoietic stem cell transplant (HSCT) is a curative therapy for malignant and non-malignant conditions. However, complications post-HSCT contribute to significant morbidity and mortality in this population. Acute kidney injury (AKI) is common in the post-allogeneic transplant phase and contributes to morbidity in this population. Continuous renal replacement therapy (CRRT) is used often in the setting of AKI or multiorgan dysfunction in critically ill children. In addition, CRRT can be useful in many disease processes related to transplant and can potentially improve outcomes in this population. This review will focus on the use of CRRT in critically ill children in the post-HSCT setting outside the realm of acute renal failure and highlight the benefits and applications of this modality in this high-risk population.

Diffuse Alveolar Hemorrhage After Pediatric Hematopoietic Stem Cell Transplantation.

Pulmonary complications are common following hematopoietic cell transplantation (HCT) and contribute significantly to its morbidity and mortality. Diffuse alveolar hemorrhage is a devastating non-infectious complication that occurs in up to 5% of patients post-HCT. Historically, it carries a high mortality burden of 60-100%. The etiology remains ill-defined but is thought to be due to lung injury from conditioning regimens, total body irradiation, occult infections, and other comorbidities such as graft vs. host disease, thrombotic microangiopathy, and subsequent cytokine release and inflammation. Clinically, patients present with hypoxemia, dyspnea, and diffuse opacities consistent with an alveolar disease process on chest radiography. Diagnosis is most commonly confirmed with bronchoscopy findings of progressively bloodier bronchoalveolar lavage or the presence of hemosiderin-laden macrophages on microscopy. Treatment with glucocorticoids is common though dosing and duration of therapy remains variable. Other agents, such as aminocaproic acid, tranexamic acid, and activated recombinant factor VIIa have also been tried with mixed results. We present a review of diffuse alveolar hemorrhage with a focus on its pathogenesis and treatment options.

Abnormal Vital Signs Predict Critical Deterioration in Hospitalized Pediatric Hematology-Oncology and Post-hematopoietic Cell Transplant Patients.

Introduction: Hospitalized pediatric hematology-oncology and post-hematopoietic cell transplant (HCT) patients have frequent deterioration requiring Pediatric Intensive Care Unit (PICU) care. Critical deterioration (CD), defined as unplanned PICU transfer requiring life-sustaining interventions within 12 h, is a pragmatic metric to evaluate emergency response systems (ERS) in pediatrics, however, it has not been investigated in these patients. The goal of this study was to evaluate if CD is an appropriate metric to assess effectiveness of ERS in pediatric hematology-oncology and post-HCT patients and if it is preceded by an actionable period of vital sign changes. Methods: A retrospective review of all unplanned PICU transfers and floor cardiopulmonary arrests in a dedicated pediatric hematology-oncology hospital between August 2014 and July 2016. Vital signs and physical exam findings 48 h prior to events were converted to Pediatric Early Warning System-Like Scores (PEWS-LS) using cardiovascular, respiratory, and neurologic criteria. Results: There were 220 deterioration events, with 107 (48.6%) meeting criteria for CD, representing a rate of 2.98 per 1,000-inpatient-days. Using the first event per hospitalization (n = 184), patients with CD had higher mortality (17.4 vs. 7.6%, p = 0.045), fewer median ICU-free-days (21 vs. 24, p = 0.011), ventilator-free-days (25 vs. 28, p < 0.001), and vasoactive-free-days (27 vs. 28, p < 0.001). Using vital sign data 48 h prior to deterioration events, those with CD had higher PEWS-LS on PICU admission (p < 0.001), spent more time with elevated PEWS-LS prior to PICU transfer (p = 0.008 to 0.023) and had a longer time from first abnormal PEWS-LS (p = 0.007 to 0.043). Significant difference between the two groups was observed as early as 4 h prior to the event (p = 0.047). Conclusion: Hospitalized pediatric hematology-oncology and post-HCT patients have frequent deterioration resulting in a high mortality. In these patients, CD is over 13 times more common than floor cardiopulmonary arrests and associated with higher mortality and fewer event-free days, making it a useful metric in these patients. CD is preceded by a long duration of abnormal vital signs, making it potentially preventable through earlier recognition.

Impact of Race and Ethnicity on End-of-Life Experiences for Children With Cancer.

BACKGROUND: Racial and ethnic disparities in the provision of end-of-life care are well described in the adult oncology literature. However, the impact of racial and ethnic disparities at end of life in the context of pediatric oncology remains poorly understood. OBJECTIVE: To investigate associations between end-of-life experiences and race/ethnicity for pediatric patients with cancer. METHODS: A retrospective cohort study was conducted on 321 children with cancer enrolled on a palliative care service at an urban pediatric cancer who died between 2011 and 2015. RESULTS: Compared to white patients, black patients were more likely to receive cardiopulmonary resuscitation (CPR; odds ratio [OR]: 4.109, confidence interval [CI]: 1.432-11.790, P = .009) and underwent 3.136 (CI: 1.433-6.869, P = .004) CPR events for every 1 white patient CPR event. The remainder of variables related to treatment and end-of-life care were not significantly correlated with race. Hispanic patients were less likely to receive cancer-directed therapy within 28 days prior to death (OR: 0.493, CI: 0.247-0.982, P = .044) as compared to non-Hispanic patients, yet they were more likely to report a goal of cure over comfort as compared to non-Hispanic patients (OR: 3.094, CI: 1.043-9.174, P = .042). The remainder of variables were not found to be significantly correlated with ethnicity. CONCLUSIONS: Race and ethnicity influenced select end-of-life variables for pediatric palliative oncology patients treated at a large urban pediatric cancer center. Further multicenter investigation is needed to ascertain the impact of racial/ethnic disparities on end-of-life experiences of children with cancer.

Predictors of Location of Death for Children with Cancer Enrolled on a Palliative Care Service.

BACKGROUND: In the U.S., more children die from cancer than from any other disease, and more than one third die in the hospital setting. These data have been replicated even in subpopulations of children with cancer enrolled on a palliative care service. Children with cancer who die in high-acuity inpatient settings often experience suffering at the end of life, with increased psychosocial morbidities seen in their bereaved parents. Strategies to preemptively identify children with cancer who are more likely to die in high-acuity inpatient settings have not been explored. MATERIALS AND METHODS: A standardized tool was used to gather demographic, disease, treatment, and end-of-life variables for 321 pediatric palliative oncology (PPO) patients treated at an academic pediatric cancer center who died between 2011 and 2015. Multinomial logistic regression was used to predict patient subgroups at increased risk for pediatric intensive care unit (PICU) death. RESULTS: Higher odds of dying in the PICU were found in patients with Hispanic ethnicity (odds ratio [OR], 4.02; p = .002), hematologic malignancy (OR, 7.42; p < .0001), history of hematopoietic stem cell transplant (OR, 4.52; p < .0001), total number of PICU hospitalizations (OR, 1.98; p < .0001), receipt of cancer-directed therapy during the last month of life (OR, 2.96; p = .002), and palliative care involvement occurring less than 30 days before death (OR, 4.7; p < .0001). Conversely, lower odds of dying in the PICU were found in patients with hospice involvement (OR, 0.02; p < .0001) and documentation of advance directives at the time of death (OR, 0.37; p = .033). CONCLUSION: Certain variables may predict PICU death for PPO patients, including delayed palliative care involvement. Preemptive identification of patients at risk for PICU death affords opportunities to study the effects of earlier palliative care integration and increased discussions around preferred location of death on end-of-life outcomes for children with cancer and their families. IMPLICATIONS FOR PRACTICE: Children with cancer who die in high-acuity inpatient settings often experience a high burden of intensive therapy at the end of life. Strategies to identify patients at higher risk of dying in the pediatric intensive care unit (PICU) have not been explored previously. This study finds that certain variables may predict PICU death for pediatric palliative oncology patients, including delayed palliative care involvement. Preemptive identification of patients at risk for PICU death affords opportunities to study the effects of earlier palliative care integration and increased discussions around preferred location of death on end-of-life outcomes for children with cancer and their families.

Predictors of Late Palliative Care Referral in Children With Cancer.

CONTEXT: Early integration of palliative care (PC) in the management of children with high-risk cancer is widely endorsed by patients, families, clinicians, and national organizations. However, optimal timing for PC consultation is not standardized, and variables that influence timing of PC integration for children with cancer remain unknown. OBJECTIVES: To investigate associations between demographic, disease, treatment, and end-of-life attributes and timing of PC consultation for children with high-risk cancer enrolled on a PC service. METHODS: A comprehensive standardized tool was used to abstract data from the medical records of 321 patients treated at a large academic pediatric cancer center, who died between 2011 and 2015. RESULTS: Gender, race, ethnicity, enrollment on a Phase I protocol, number of high-acuity hospitalizations, and receipt of cardiopulmonary resuscitation were not associated with timing of PC involvement. Patients with hematologic malignancy, those who received cancer-directed therapy during the last month of life, and those with advance directives documented one week or less before death had higher odds of late PC referral (malignancy: odds ratio [OR] 3.24, P = 0.001; therapy: OR 4.65, P < 0.001; directive: OR 4.81, P < 0.0001). Patients who received hospice services had lower odds of late PC referral <30 days before death (OR 0.31, P < 0.001). CONCLUSION: Hematologic malignancy, cancer-directed therapy at the end of life, and delayed documentation of advance directives are associated with late PC involvement in children who died of cancer. Identification of these variables affords opportunities to study targeted interventions to enhance access to earlier PC resources and services for children with high-risk cancer and their families.

Illness and end-of-life experiences of children with cancer who receive palliative care.

BACKGROUND: The field of pediatric palliative oncology is newly emerging. Little is known about the characteristics and illness experiences of children with cancer who receive palliative care (PC). METHODS: A retrospective cohort study of 321 pediatric oncology patients enrolled in PC who died between 2011 and 2015 was conducted at a large academic pediatric cancer center using a comprehensive standardized data extraction tool. RESULTS: The majority of pediatric palliative oncology patients received experimental therapy (79.4%), with 40.5% enrolled on a phase I trial. Approximately one-third received cancer-directed therapy during the last month of life (35.5%). More than half had at least one intensive care unit hospitalization (51.4%), with this subset demonstrating considerable exposure to mechanical ventilation (44.8%), invasive procedures (20%), and cardiopulmonary resuscitation (12.1%). Of the 122 patients who died in the hospital, 44.3% died in the intensive care unit. Patients with late PC involvement occurring less than 30 days before death had higher odds of dying in the intensive care unit over the home/hospice setting compared to those with earlier PC involvement (OR: 4.7, 95% CI: 2.47-8.97, P < 0.0001). CONCLUSIONS: Children with cancer who receive PC experience a high burden of intensive treatments and often die in inpatient intensive care settings. Delayed PC involvement is associated with increased odds of dying in the intensive care unit. Prospective investigation of early PC involvement in children with high-risk cancer is needed to better understand potential impacts on cost-effectiveness, quality of life, and delivery of goal concordant care.

Transcriptomic effects of adenosine 2A receptor deletion in healthy and endotoxemic murine myocardium.

Influences of adenosine 2A receptor (A2AR) activity on the cardiac transcriptome and genesis of endotoxemic myocarditis are unclear. We applied transcriptomic profiling (39 K Affymetrix arrays) to identify A2AR-sensitive molecules, revealed by receptor knockout (KO), in healthy and endotoxemic hearts. Baseline cardiac function was unaltered and only 37 A2AR-sensitive genes modified by A2AR KO (≥1.2-fold change, <5 % FDR); the five most induced are Mtr, Ppbp, Chac1, Ctsk and Cnpy2 and the five most repressed are Hp, Yipf4, Acta1, Cidec and Map3k2. Few canonical paths were impacted, with altered Gnb1, Prkar2b, Pde3b and Map3k2 (among others) implicating modified G protein/cAMP/PKA and cGMP/NOS signalling. Lipopolysaccharide (LPS; 20 mg/kg) challenge for 24 h modified >4100 transcripts in wild-type (WT) myocardium (≥1.5-fold change, FDR < 1 %); the most induced are Lcn2 (+590); Saa3 (+516); Serpina3n (+122); Cxcl9 (+101) and Cxcl1 (+89) and the most repressed are Car3 (-38); Adipoq (-17); Atgrl1/Aplnr (-14); H19 (-11) and Itga8 (-8). Canonical responses centred on inflammation, immunity, cell death and remodelling, with pronounced amplification of toll-like receptor (TLR) and underlying JAK-STAT, NFκB and MAPK pathways, and a 'cardio-depressant' profile encompassing suppressed ß-adrenergic, PKA and Ca2+ signalling, electromechanical and mitochondrial function (and major shifts in transcripts impacting function/injury including Lcn2, S100a8/S100a9, Icam1/Vcam and Nox2 induction, and Adipoq, Igf1 and Aplnr repression). Endotoxemic responses were selectively modified by A2AR KO, supporting inflammatory suppression via A2AR sensitive shifts in regulators of NFκB and JAK-STAT signalling (IκBζ, IκBα, STAT1, CDKN1a and RRAS2) without impacting the cardio-depressant gene profile. Data indicate A2ARs exert minor effects in un-stressed myocardium and selectively suppress NFκB and JAK-STAT signalling and cardiac injury without influencing cardiac depression in endotoxemia.

A Critical Care and Transplantation-Based Approach to Acute Respiratory Failure after Hematopoietic Stem Cell Transplantation in Children.

Acute respiratory failure contributes significantly to nonrelapse mortality after allogeneic hematopoietic stem cell transplantation. Although there is a trend of improved survival over time, mortality remains unacceptably high. An understanding of the pathophysiology of early respiratory failure, opportunities for targeted therapy, assessment of the patient at risk, optimal use of noninvasive positive pressure ventilation, strategies to improve alveolar recruitment, appropriate fluid management, care of the patient with chronic lung disease, and importantly, a team approach between critical care and transplantation services may improve outcomes.

A1 adenosine receptor deficiency or inhibition reduces atherosclerotic lesions in apolipoprotein E deficient mice.

AIMS: The goal of this study was to determine whether the A1 adenosine receptor (AR) plays a role in atherosclerosis development and to explore its potential mechanisms. METHODS AND RESULTS: Double knockout (DKO) mice, deficient in the genes encoding A1 AR and apolipoprotein E (apoE), demonstrated reduced atherosclerotic lesions in aortic arch (en face), aortic root, and innominate arteries when compared with apoE-deficient mice (APOE-KO) of the same age. Treating APOE-KO with an A1 AR antagonist (DPCPX) also led to a concentration-dependent reduction in lesions. The total plasma cholesterol and triglyceride levels were not different between DKO and APOE-KO; however, higher triglyceride was observed in DKO fed a high-fat diet. DKO also had higher body weights than APOE-KO. Plasma cytokine concentrations (IL-5, IL-6, and IL-13) were significantly lower in DKO. Proliferating cell nuclear antigen expression was also significantly reduced in the aorta from DKO. Despite smaller lesions in DKO, the composition of the innominate artery lesion and cholesterol loading and efflux from bone marrow-derived macrophages of DKO were not different from APOE-KO. CONCLUSION: The A1 AR may play a role in the development of atherosclerosis, possibly due to its pro-inflammatory and mitogenic properties.

Clinical outcomes of children receiving intensive cardiopulmonary support during hematopoietic stem cell transplant.

OBJECTIVE: We investigated the short-term and 1-year clinical outcomes of 129 children who received intensive cardiopulmonary support during hematopoietic stem cell transplant. Intensive cardiopulmonary support was defined as receiving at least one of the following interventions: continuous positive pressure ventilation, dopamine infusion greater than or equal to 10 mcg/kg/minute, or the use of any other vasoactive infusion. Duration of intensive cardiopulmonary support, survival to hospital discharge, and predictors of these outcome variables were compared with 387 hematopoietic stem cell transplant patients who did not receive intensive support during the same period. We also report the 1-year survival; presence of chronic graft-versus-host disease; and renal, cardiac, and pulmonary function for all patients. DESIGN: A multicenter retrospective cohort study. SETTING: The ICU and hematopoietic stem cell transplant unit of nine pediatric tertiary care centers. PATIENTS: Children undergoing hematopoietic stem cell transplant who required intensive cardiopulmonary support. INTERVENTIONS: None. RESULTS: Predictors of the need for intensive support included unrelated donor allogeneic transplant, glomerular filtration rate less than 85 mL/minute/1.73 m, and nonmalignant disease as the indication for transplant. The survival to discontinuation of intensive support for all patients was 62% and 58% for patients who received invasive mechanical ventilatory support. The duration of mechanical ventilation was not predictive of survival. Predictors of intensive support mortality included macroscopic bleeding, engraftment, and pediatric logistic organ dysfunction score greater than one in two domains. Survival to hospital discharge was 50% for the intensive support group and 99% for the nonintensive support group. Overall 1-year survival was 40% in the intensive support population and 65% in the nonintensive support group. There were no significant differences in the survival, rates of chronic graft-versus-host disease, creatinine, forced expiratory volume in 1-minute, cardiac shortening fraction, or performance status in intensive and nonintensive support patients who survived to hospital discharge. CONCLUSION: Intensive cardiopulmonary support plays an important and potentially life-saving role in the care of pediatric stem cell transplant patients. Survivors of intensive support do not have compromised 1-year survival or organ function compared with children who did not receive intensive support.

The adenosine A2A receptor - myocardial protectant and coronary target in endotoxemia.

BACKGROUND: Cardiac injury and dysfunction are contributors to disease progression and mortality in sepsis. This study evaluated the cardiovascular role of intrinsic A2A adenosine receptor (A2AAR) activity during lipopolysaccharide (LPS)-induced inflammation. METHODS: We assessed the impact of 24 h of LPS challenge (20 mg/kg, IP) on cardiac injury, coronary function and inflammatory mediator levels in Wild-Type (WT) mice and mice lacking functional A2AARs (A2AAR KO). RESULTS: Cardiac injury was evident in LPS-treated WTs, with ~7-fold elevation in serum cardiac troponin I (cTnI), and significant ventricular and coronary dysfunction. Absence of A2AARs increased LPS-provoked cTnI release at 24 h by 3-fold without additional demise of contraction function. Importantly, A2AAR deletion per se emulated detrimental effects of LPS on coronary function, and LPS was without effect in coronary vessels lacking A2AARs. Effects of A2AAR KO were independent of major shifts in circulating C-reactive protein (CRP) and haptoglobin. Cytokine responses were largely insensitive to A2AAR deletion; substantial LPS-induced elevations (up to 100-fold) in IFN-γ and IL-10 were unaltered in A2AAR KO mice, as were levels of IL-4 and TNF-α. However, late elevations in IL-2 and IL-5 were differentially modulated by A2AAR KO (IL-2 reduced, IL-5 increased). Data demonstrate that in the context of LPS-triggered cardiac and coronary injury, A2AAR activity protects myocardial viability without modifying contractile dysfunction, and selectively modulates cytokine (IL-2, IL-5) release. A2AARs also appear to be targeted by LPS in the coronary vasculature. CONCLUSIONS: These experimental data suggest that preservation of A2AAR functionality might provide therapeutic benefit in human sepsis.

Continuous renal replacement therapy in children post-hematopoietic stem cell transplantation: the present and the future.

Allogeneic hematopoietic stem cell transplantation (HSCT) use has expanded markedly to treat different disorders like hematologic malignancies, immunodeficiency, and inborn errors of metabolism. However, it is commonly associated with complications that limit the benefit of this therapy. Acute renal failure occurs commonly after HSCT and results in increased risk of mortality. In many instances, children post-HSCT develop acute renal insufficiency in the context of other organ failure, necessitating intensive care unit admission for management. Recently, continuous renal replacement therapy (CRRT) has emerged as the favored modality of renal replacement therapy in the care of critically ill children who are hemodynamically unstable. Currently, CRRT is being utilized more often in the care of critically ill post- HSCT children to treat renal failure or to prevent fluid overload (FO). FO > 20% has been shown in many studies to be an independent risk of mortality in critically ill children and therefore, many clinicians will initiate this therapy due to FO even without overt renal failure. CRRT may be beneficial in disease processes as acute lung injury due to removal of fluid. CRRT results in improved oxygenation in post-HSCT children with acute lung injury and this improvement is sustained for at least 48 hours after initiation of this therapy. Survival in post-HSCT children requiring this therapy ranges from 17% to 45%, however, long term survival is still poor. This review will discuss current practice of CRRT in children post-HSCT, as well as future directions.

Severe H1N1-associated acute respiratory failure in immunocompromised children.

BACKGROUND: Severe pandemic influenza A (H1N1) infection can lead to acute respiratory failure (ARF) with associated high mortality. Children with malignancy may be at higher risk of H1N1-associated ARF because of underlying primary disease or immunosuppression associated with chemotherapy. PROCEDURE: We describe the clinical course and outcome of critically ill pediatric oncology/hematology patients with H1N1-associated ARF. RESULTS: Five patients were admitted to the St. Jude Children's Research Hospital (SJCRH) ICU with H1N1 infection during the 2009-2010 influenza season. Underlying diagnoses included 2 patients with acute lymphoblastic leukemia and one each with neuroblastoma, brainstem glioma, and hemolytic anemia secondary to pyruvate kinase deficiency. All patients were mechanically ventilated secondary to ARF following unsuccessful trials of non-invasive ventilatory support. The majority of patients (4/5) required inotropic support, and none required dialysis. Further measures to support their ARF included high frequency oscillatory ventilation in 2 patients, nitric oxide in 3 patients, and surfactant in 1 patient. Three patients had bronchopleural air leak. All patients received oseltamivir; however, 2 were switched to intravenous zanamivir once resistance to oseltamivir was documented. Mean duration of mechanical ventilation was 24 ± 6.8 days and mean duration of ICU admission was 37 ± 12 days. All patients survived to hospital discharge. CONCLUSION: Our series suggests an overall favorable outcome in immunocompromised children with H1N1-related ARF. Our experience underscores the value of aggressive support during H1N1-related ARF, and early detection and management of oseltamivir-resistant H1N1 infection in this high-risk population.

Impact of continuous renal replacement therapy on oxygenation in children with acute lung injury after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Acute lung injury (ALI) continues to carry a high mortality rate in children after allogeneic hematopoietic stem cell transplant (HSCT). Continuous renal replacement therapy (CRRT) is often used for these patients for various indications including renal failure and fluid overload, and may have a beneficial effect on oxygenation and survival. Therefore, we sought to determine the effect of CRRT on oxygenation in mechanically ventilated pediatric allogeneic HSCT patients with ALI, and to document survival to intensive care unit discharge in this at-risk population receiving both mechanical ventilation and CRRT. PROCEDURE: Retrospective analysis of a pediatric allogeneic HSCT cohort admitted to intensive care unit of a single pediatric oncology center from 1994 to 2006 who received CRRT during a course of mechanical ventilation for ALI. RESULTS: Thirty post-HSCT mechanically ventilated children with ALI who underwent CRRT were included. There was a significant improvement in PaO(2)/FiO(2) with median increase of 31 and 43 in the 24 and 48 hr intervals after initiation of CRRT compared with the 24 hr interval before CRRT (P = 0.0008 and 0.0062, respectively). This improvement in PaO(2)/FiO(2) correlated significantly with reduction of fluid balance achieved after initiation of CRRT (P = 0.0001). There was a trend not reaching statistical significance in improvement in mean airway pressure 48 hr after CRRT in survivors compared to non-survivors. CONCLUSIONS: CRRT improved oxygenation in mechanically ventilated pediatric allogeneic HSCT patients with ALI.

Protection from doxorubicin-induced cardiomyopathy using the modified anthracycline N-benzyladriamycin-14-valerate (AD 198).

The anthracycline doxorubicin (Dox) is an effective antitumor agent. However, its use is limited because of its toxicity in the heart. N-Benzyladriamycin-14-valerate (AD 198) is a modified anthracycline with antitumor efficacy similar to that of Dox, but with significantly less cardiotoxicity and potentially cardioprotective elements. In the present study, we investigated the possibility of in vivo protective effects of low-dose AD 198 against Dox-induced cardiomyopathy. To do this, rats were divided into four groups: vehicle, Dox (20 mg/kg; single injection day 1), AD 198 (0.3 mg/kg per injection; injections on days 1, 2, and 3), or a combination treatment of Dox + AD 198. Seventy-two hours after beginning treatment, hearts from the Dox group had decreased phosphorylation of AMP kinase and troponin I and reduced poly(ADP-ribose) polymerase, ß-tubulin, and serum albumin expression. Dox also increased the phosphorylation of phospholamban and expression of inducible nitric-oxide synthase in hearts. Each of these Dox-induced molecular changes was attenuated in the Dox + AD 198 group. In addition, excised hearts from rats treated with Dox had a 25% decrease in left ventricular developed pressure (LVDP) and a higher than normal increase in LVDP when perfused with a high extracellular Ca(2+) solution. The Dox-induced decrease in baseline LVDP and hyper-responsiveness to [Ca(2+)] was not observed in hearts from the Dox + AD 198 group. Thus Dox, with well established and efficient antitumor protocols, in combination with low levels of AD 198, to counter anthracycline cardiotoxicity, may be a promising next step in chemotherapy.

Outcomes of hematopoietic stem cell transplant patients who received continuous renal replacement therapy in a pediatric oncology intensive care unit.

OBJECTIVES: To assess the long-term benefits of continuous renal replacement therapy (CRRT) in this patient population and to analyze factors associated with survival. Hematopoietic stem cell transplantation is being utilized as curative therapy for a variety of disorders. However, organ dysfunction is commonly associated with this therapy. Continuous renal replacement therapy (CRRT) is increasingly being used in the treatment of this multiorgan dysfunction. DESIGN: Retrospective cohort study. SETTING: A free-standing, tertiary care, pediatric oncology hospital. PATIENTS: Twenty-nine allogeneic hematopoietic stem cell transplantation patients who underwent 33 courses of CRRT in the intensive care unit between January 2003 and December 2007. INTERVENTIONS: Cox proportional hazards regressions models were used to examine the relationship between demographic and clinical variables and length of survival. MEASUREMENTS AND MAIN RESULTS: The median length of survival post CRRT initiation was 31 days; only one patient survived >6 mos. Factors associated with increased risk of death included: higher bilirubin and blood urea nitrogen levels before and at 48 hrs into CRRT, lower Pao2/Fio2 ratios at 48 hrs of CRRT, and higher C-reactive protein levels, as well as lower absolute neutrophil counts at CRRT end. CONCLUSION: In this single-center study, CRRT was not associated with long-term survival in pediatric allogeneic hematopoietic stem cell transplantation patients. Clinical data exist, both before and during CRRT, that may be associated with length of survival. Lower C-reactive protein levels at CRRT end were associated with longer survival, suggesting that the ability to attenuate inflammation during CRRT may afford a survival advantage. These findings require confirmation in a prospective study.