Mara Nitu

Invasive Mechanical Ventilation and Mortality in Pediatric Hematopoietic Stem Cell Transplantation: A Multicenter Study.

Objective: To establish the current respiratory practice patterns in pediatric hematopoietic stem cell transplant patients and investigate their associations with mortality across multiple centers. Design: Retrospective cohort between 2009 and 2014. Setting: Twelve children’s hospitals in the United States. Patients: Two hundred twenty-two pediatric allogeneic hematopoietic stem cell transplant recipients with acute respiratory failure using invasive mechanical ventilation. Interventions: None. Measurements and Main Results: PICU mortality of our cohort was 60.4%. Mortality at 180 days post PICU discharge was 74%. Length of PICU stay prior to initiation of invasive mechanical ventilation was significantly lower in survivors, and the odds of mortality increased for longer length of PICU stay prior to intubation. A total of 91 patients (41%) received noninvasive ventilation at some point during their PICU stay prior to intubation. Noninvasive ventilation use preintubation was associated with increased mortality (odds ratio, 2.1; 95% CI, 1.2–3.6; p = 0.010). Patients ventilated longer than 15 days had higher odds of death (odds ratio, 2.4; 95% CI, 1.3–4.2; p = 0.004). Almost 40% of patients (n = 85) were placed on high-frequency oscillatory ventilation with a mortality of 76.5% (odds ratio, 3.3; 95% CI, 1.7–6.5; p = 0.0004). Of the 20 patients who survived high-frequency oscillatory ventilation, 18 were placed on high-frequency oscillatory ventilation no later than the third day of invasive mechanical ventilation. In this subset of 85 patients, transition to high-frequency oscillatory ventilation within 2 days of the start of invasive mechanical ventilation resulted in a 76% decrease in the odds of death compared with those who transitioned to high-frequency oscillatory ventilation later in the invasive mechanical ventilation course. Conclusions: This study suggests that perhaps earlier more aggressive critical care interventions in the pediatric hematopoietic stem cell transplant patient with respiratory failure requiring invasive mechanical ventilation may offer an opportunity to improve outcomes.

Alteplase use for malfunctioning central venous catheters correlates with catheter-associated bloodstream infections.

Objectives: A catheter thrombosis and the presence of a catheter-associated bloodstream infection (CBSI) often occur simultaneously, but it is unclear if or to what degree the two complications relate. Several animal and adult studies indicate a relationship between fibrin sheaths and thrombi in the development of CBSIs. To date, there has been limited human investigation in the pediatric population to determine a clear link between the presence of a thrombus and bacteremia. The use of alteplase for malfunctioning central venous catheter may indicate the formation of intraluminal thrombus or fibrin sheath. A catheter that requires alteplase is at higher risk of a CBSI. Design: A retrospective chart review from July 2008 to December 2010. Setting: PICU. Patients: All patients with central catheters admitted to the PICU. Interventions: No interventions performed with the retrospective study. Measurements: Number of total central venous catheters, number of central venous catheters that received treatment with alteplase, and number of CBSIs. Main Results: Preliminary data during the study period identified 3,289 central venous catheters. Twelve percent of these catheters required at least one dose of alteplase. There were 40 CBSIs during this same time period of which 28% received alteplase during the 5 days preceding the positive blood culture. The odds ratio for getting a CBSI when alteplase is administered is 2.87 (confidence interval 1.42–5.80; p = 0.002). The average age of the central venous catheters at time of infection was not statistically different, 16.1 days in the alteplase catheters compared with 25.6 days for the catheters that did not receive alteplase (p = 0.6). Conclusions: There is a positive correlation between the use of alteplase for malfunctioning central venous catheters and the development of a CASBI. This is likely associated with the presence of an intraluminal fibrin sheath or thrombus. This study adds evidence linking thrombus formation to CBSI.

An Evaluation of Various Ventilator-Associated Infection Criteria in a PICU.

Objective: To describe characteristics and overlap associated with various ventilator-associated infection criteria in the PICU. Design: Retrospective observational study. Setting: A quaternary care children’s hospital PICU. Patients: Children ventilated more than 48 hours, excluding patients with tracheostomy. Interventions: None. Measurements and Main Results: Ventilator-associated infection, including pneumonia, infection-related ventilator-associated condition, tracheobronchitis, and lower respiratory tract infection were defined according to criteria from the Centers for Disease Control and Prevention or medical literature. Clinical data were abstracted to assign diagnoses of each ventilator-associated infection. In 300 episodes of mechanical ventilation, there were 30 individual episodes of ventilator-associated infection. Nine episodes met more than one definition. Rates per 1,000 ventilator days were 2.60 for ventilator-associated pneumonia, 2.16 for infection-related ventilator-associated condition, 5.19 for ventilator-associated tracheobronchitis, and 6.92 for lower respiratory tract infection. The rate of any ventilator-associated infection was 12.98 per 1,000 ventilator days. Individual criteria had similar risk factors and outcomes. Risk factors for development of any ventilator-associated infection included older age (p = 0.003) and trauma (p = 0.007), while less cardiac surgery patients developed ventilator-associated infection (p = 0.015). On multivariate analysis, trauma was the only independent risk factor (adjusted odds ratio, 3.10; 95% CI, 1.15–8.38). Developing any ventilator-associated infection was associated with longer duration of mechanical ventilation (p < 0.001) and longer PICU length of stay (p < 0.001) but not PICU mortality (p = 0.523). Conclusions: There is little overlap in diagnosis of various ventilator-associated infection. However, the risk factors and outcomes associated with individual criteria are similar, indicating that they may have validity in identifying true pathology. Ventilator-associated infection in general is likely a larger problem than indicated by low hospital-reported rates of ventilator-associated pneumonia. There is clinical confusion due to the presence of several diagnostic criteria for ventilator-associated infection. Developing a more inclusive and clinically relevant criterion for diagnosing ventilator-associated infection is warranted to accurately assess their impact and improve guidance for clinicians in evaluating and treating ventilator-associated infection.

Pediatric Acute Respiratory Distress Syndrome in Pediatric Allogeneic Hematopoietic Stem Cell Transplants: A Multicenter Study

Objective: Immunodeficiency is both a preexisting condition and a risk factor for mortality in pediatric acute respiratory distress syndrome. We describe a series of pediatric allogeneic hematopoietic stem cell transplant patients with pediatric acute respiratory distress syndrome based on the recent Pediatric Acute Lung Injury Consensus Conference guidelines with the objective to better define survival of this population. Design: Secondary analysis of a retrospective database. Setting: Twelve U.S. pediatric centers. Patients: Pediatric allogeneic hematopoietic stem cell transplant recipients requiring mechanical ventilation. Interventions: None. Measurements and Main Results: During the first week of mechanical ventilation, patients were categorized as: no pediatric acute respiratory distress syndrome or mild, moderate, or severe pediatric acute respiratory distress syndrome based on oxygenation index or oxygen saturation index. Univariable logistic regression evaluated the association between pediatric acute respiratory distress syndrome and PICU mortality. A total of 91.5% of the 211 patients met criteria for pediatric acute respiratory distress syndrome using the Pediatric Acute Lung Injury Consensus Conference definition: 61.1% were severe, 27.5% moderate, and 11.4% mild. Overall survival was 39.3%. Survival decreased with worsening pediatric acute respiratory distress syndrome: no pediatric acute respiratory distress syndrome 66.7%, mild 63.6%, odds ratio = 1.1 (95% CI, 0.3–4.2; p = 0.84), moderate 52.8%, odds ratio = 1.8 (95% CI, 0.6–5.5; p = 0.31), and severe 24.6%, odds ratio = 6.1 (95% CI, 2.1–17.8; p < 0.001). Nonsurvivors were more likely to have multiple consecutive days at moderate and severe pediatric acute respiratory distress syndrome (p < 0.001). Moderate and severe patients had longer PICU length of stay (p = 0.01) and longer mechanical ventilation course (p = 0.02) when compared with those with mild or no pediatric acute respiratory distress syndrome. Nonsurvivors had a higher median maximum oxygenation index than survivors at 28.6 (interquartile range, 15.5–49.9) versus 15.0 (interquartile range, 8.4–29.6) (p < 0.0001). Conclusion: In this multicenter cohort, the majority of pediatric allogeneic hematopoietic stem cell transplant patients with respiratory failure met oxygenation criteria for pediatric acute respiratory distress syndrome based on the Pediatric Acute Lung Injury Consensus Conference definition within the first week of invasive mechanical ventilation. Length of invasive mechanical ventilation, length of PICU stay, and mortality increased as the severity of pediatric acute respiratory distress syndrome worsened.

Vasovagal syncope and severe bradycardia following intranasal dexmedetomidine for pediatric procedural sedation

We report syncope and bradycardia in an 11‐year‐old girl following administration of intranasal dexmedetomidine for sedation for a voiding cystourethrogram. Following successful completion of VCUG and a 60‐min recovery period, the patients level of consciousness and vital signs returned to presedation levels. Upon leaving the sedation area, the patient collapsed, with no apparent inciting event. The patient quickly regained consciousness and no injury occurred. The primary abnormality found was persistent bradycardia, and she was admitted to the hospital for telemetric observation. The bradycardia lasted ~2 h, and further cardiac workup revealed no underlying abnormality. Unanticipated and previously unreported outcomes may be witnessed as we expand the use of certain sedatives to alternative routes of administration.

High-frequency oscillatory ventilators in burn patients: experience of Riley Hospital for Children.

The objective of the study is to review a single institution’s experience with high-frequency oscillatory ventilation (HFOV) and compare patient characteristics, outcomes, and complications with other reported studies of HFOV use in burn patients with acute respiratory distress syndrome and respiratory failure. This study is a retrospective chart review of the burn patients treated with HFOV in Pediatric Burn Unit at Riley Hospital for Children from October 1996 to April 2007. Patient data were collected, including demographics, percentage of TBSA burn, percentage of full-thickness burn, mechanisms of burn, settings on conventional mechanical ventilation and HFOV, and blood gas data before initiation of HFOV and at 1, 3, 6, 12, 24, 72 (3 days), 120 (5 days), 168 (7 days), 240 (10 days), and 336 hours (14 days). Length of stay, mortality, and complications were also included. HFOV was used 24 times in 21 patients between October 1996 and April 2007 with a mean age of 10 ± 11 years. At initiation of HFOV, the PaO2/FiO2 and oxygenation index values were 109 ± 26 and 36 ± 12, respectively. At stop, the PaO2/FiO2 improved to 166 ± 24 with an average increase from before HFOV of 57 ± 39 (P < .002). At 5 days of HFOV, oxygenation index improved to 14.1 ± 1.7 (P < .02) but did not significantly improve at discontinuation of HFOV at 28.8 ± 6.2 (P = .11). The mortality rate during admission to the burn unit was 29%. Barotrauma occurred in 38% of patients during HFOV. Severe hypercapnea was present briefly in 49% of patients, and this was refractory to standard treatment in 19%. In our experience, HFOV in severe burn patients has significant, early, and sustained improvement in oxygenation. Earlier institution of HFOV seems to significantly lower rates of barotraumas.

High dose dexmedetomidine: effective as a sole agent sedation for children undergoing MRI.

Objective. To determine the efficacy and safety of high dose dexmedetomidine as a sole sedative agent for MRI. We report our institutions experience. Design. A retrospective institutional review of dexmedetomidine usage for pediatric MRI over 5.5 years. Protocol included a dexmedetomidine bolus of 2 μg/kg intravenously over ten minutes followed by 1 μg/kg/hr infusion. 544 patients received high dose dexmedetomidine for MRI. A second bolus was used in 103 (18.9%) patients. 117 (21.5%) required additional medications. Efficacy, side effects, and use of additional medicines to complete the MRI were reviewed. Data was analyzed using Students t-test, Fishers exact test, and Analysis of Variance (ANOVA). Main Results. Dexmedetomidine infusion was associated with bradycardia (3.9%) and hypotension (18.4%). None of the patients required any intervention. Vital signs were not significantly different among the subgroup of patients receiving one or two boluses of dexmedetomidine or additional medications. Procedure time was significantly shorter in the group receiving only one dexmedetomidine bolus and increased with second bolus or additional medications (P < 0.0001). Discharge time was longer for children experiencing bradycardia (P = 0.0012). Conclusion. High dose Dexmedetomidine was effective in 78.5% of cases; 21.5% of patients required additional medications. Side effects occurred in approximately 25% of cases, resolving spontaneously.

Successful use of intravenous dexmedetomidine for magnetic resonance imaging sedation in autistic children.

Objectives Autism and autism spectrum disorders (A/ASD) represent a family of neurodevelopmental conditions that are associated with overactive, difficult-to-control behaviors. Sedating these patients for magnetic resonance imaging (MRI) poses challenges. Children with A/ASD were examined against clinical controls to determine the effectiveness and safety of intravenous (IV) dexmedetomidine for deep sedation. Methods The quality assurance data on all of the children who received IV dexmedetomidine sedation for MRI between July 2007 and December 2012 were reviewed. Patients in both groups were sedated by an intensivist-based team with a standard plan of 2 &mgr;g/kg IV dexmedetomidine administered for 10 minutes followed by an infusion of 1 &mgr;g · kg−1 · hour−1. The amount of IV dexmedetomidine was titrated to the deep level of sedation. A total of 56 patients in the A/ASD group and 107 in the control group were sedated with no reported sedation failures. Sedation parameters were compared between the A/ASD and control groups using analysis of covariance models, controlling for age, sex, and weight. Results Children in the A/ASD group were predominantly male (73%) and older (6.1 ± 0.3 years) than children in the control group (56%; 5.0 ± 0.2 years; P < 0.05 for both). Procedure time was significantly shorter for patients in the A/ASD group than in control patients (34.6 ± 2.4 vs 44.3 ± 1.6 minutes; P < 0.05). The A/ASD and control groups required a similar IV bolus of dexmedetomidine (2.6 &mgr;g/kg ± 0.1 vs 2.4 &mgr;g/kg ± 0.10; P = 0.29), with a significantly lower infusion dose in the A/ASD group (0.74 &mgr;g/kg ± 0.05 vs 0.89 &mgr;g/kg ± 0.03; P < 0.05). Heart rates were similar in the A/ASD group and the control group (67.0 beats per minute ± 1.6 vs 69.3 ± 1.1 beats per minute; P = 0.250). There were no complications. Recovery time was approximately 7 minutes longer in the A/ASD group than in the control group, but this was nonsignificant (101.2 ± 3.5 minutes vs 94.2 ± 2.4 minutes; P = 0.12). Analyses were performed using analysis of covariance methods and generalized linear models to control for age, sex, and weight. Conclusions Children with A/ASD can be successfully sedated for MRIs with IV dexmedetomidine without complications.

Inconsistencies in care of the pediatric hematopoietic stem cell transplant recipient with respiratory failure: Opportunity for standardization and improved outcome

There is variability in critical care outcome of the HSCT recipient. One potential reason may be due to the inconsistent ventilation approaches. To quantitate this variability, we conducted a survey to assess self‐reported use of ventilation and adjunctive strategies for the HSCT recipient. Electronic survey, open from June 2012 through January 201, distributed through the Pediatric Acute Lung Injury and Sepsis Investigators network electronic mailing list. Ninety‐four individual responses were from 36 different institutions. The majority indicated that HSCT recipients requiring critical care were admitted to the general PICU. The vast majority (89%) endorsed routine practice of low‐tidal‐volume ventilation strategies. More than half stated that pressure‐regulated volume control is the starting mode of choice. Eighty‐three percent felt their group practiced early initiation of lung protective strategies. Eleven percent encouraged “early transition” to HFOV. Inhaled nitric oxide and milrinone were reported at the highest frequencies, but the majority used these empirically. Opinions regarding variables that affect outcomes of the HSCT were diverse. The estimated mortality of HSCT patients with respiratory was highly variable. Strategies for ventilation and oxygenation, use of HFOV, and adjunctive therapies are variable among pediatric intensivists.

Intensive Care Management of Pediatric Acute Liver Failure.

ABSTRACT Pediatric acute liver failure is rare but life-threatening illness that occurs in children without preexisting liver disease. The rarity of the disease, along with its severity and heterogeneity, presents unique clinical challenges to the physicians providing care for pediatric patients with acute liver failure. In this review, practical clinical approaches to the care of critically ill children with acute liver failure are discussed with an organ system-specific approach. The underlying pathophysiological processes, major areas of uncertainty, and approaches to the critical care management of pediatric acute liver failure are also reviewed.