Academic Pediatric Intensive Care Unit Research Articles

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Background and aims: Neurally adjusted ventilatory assist (NAVA) is a new ventilator modality with an innovative synchronization technique. Aims: Our aim is to verify if NAVA is feasible and safe in terms of physiological and clinical variables in infants recovering from severe ARDS. Methods: Infants affected by severe ARDS requiring high frequency ventilation, weaned with NAVA during 2010. Controls (2:1 ratio) were ARDS infants weaned with pressure support (PSV) during 2008–2009, matched for age, gas exchange impairment and weight.Setting: 3rd level academic pediatric intensive care units. Main outcome measures were physiological and ventilator parameters, duration of ventilator supporto in PSV or NAVA. Results: 10 infants treated with NAVA and 20 with PSV were studied. Heart rate (p<0.001) and mean arterial pressure (p<0.001) increased less during NAVA than during PSV. Similarly, PaO2/FiO2 ratio decreased less in NAVA than in PSV (p<0.001). NAVA also resulted in lower PaCO2 (p<0.001) and peak pressure (p=0.001), as well as higher minute ventilation (p=0.013). COMFORT score (p=0.004) and duration of support were lower in NAVA than in PSV (p=0.011). Conclusions: NAVA is safe and suitable in infants recovering from severe ARDS requiring HFOV as a rescue mode of ventilation. NAVA could provide better results than PSV and is worth to be investigated in a multicentre randomised trial.

Using All Patient Refined Diagnosis Related Group to Identify Cost-Management Targets

Background: Evaluate patterns in existing cost data for patients with respiratory illness managed in a large academic Pediatric Intensive Care Unit (PICU), with the goal to identify targets for potential cost-management strategies. Methods: Retrospective, observational study of patients admitted to a 34-bed multidisciplinary PICU from October 2011 to September 2012. Study design: Variable direct costs (VDC) for each All Patient Refined Diagnosis Related Group (APR DRG) were obtained from the Decision Support Group and detailed analysis was performed for top respiratory APR DRGs. Results: During the study period, 1,999 patients were admitted to the PICU equating to 17,053 PICU days. Medical critical care patients accounted for 54% of all admissions and 46% PICU days. The top 5 respiratory-related APR DRGs accounted for almost 45% of all PICU medical admissions. Non-asthma respiratory-related APR DRGs accounted for 23% of medical admission and 18% of medical PICU days. Of the total VDC for this subgroup, 54% and 20% was attributed to nursing and respiratory care respectively, with a significant minority (<10% ) on pharmacy and laboratory services. Further analysis of the VDC for respiratory care indicated one-third of all costs are incurred for pulmonary hygiene care, another third for delivery of bronchodilator therapy, and just 16.4% for mechanical ventilation. Conclusion: Analysis of VDC in context of APR DRG can indicate areas for potential cost management strategies. A high percentage of respiratory care costs accounted for pulmonary clearance interventions. This type of cost analysis may identify potential targets for cost-management interventions in various PICU populations.

The Use of Family Conferences in the Pediatric Intensive Care Unit

Data about pediatric intensive care unit (PICU) family conferences (FCs) are needed to enhance our understanding of the role of FCs in patient care and build a foundation for future research on PICU communication and decision making. The study's objective was to describe the use and content of PICU FCs. The study design was a prospective chart review comparing patients who had conferences with those who did not, and a sub-analysis of patients with chronic care conditions (CCCs). The study setting was an academic PICU from January 2011 through June 2011. Medical events under consideration were placement of tracheostomy or gastrostomy tube; initiation of chronic ventilation; palliative care involvement; use of extracorporeal membrane oxygenation, continuous renal replacement, or cardiopulmonary resuscitation; care limitation orders; death; length of stay; and discharge to a new environment. From 661 admissions, we identified 74 conferences involving 49 patients. Sixty-four conferences (86%) were held about 40 patients with CCCs. Having a conference was associated with (p<0.05): length of PICU admission; palliative care involvement; initiation of chronic ventilation; extracorporeal membrane oxygenation; cardiopulmonary resuscitation; death; discharge to a new environment; and care limitation orders. Twenty-nine percent of patients who had a new tracheostomy or gastrostomy tube placed had a conference. We identified two categories of discussion topics: information exchange and future management. Most identified FCs involved complex patients or patients who faced decisions affecting the child's quality of life or dying. For many patients who faced life changing decisions we did not identify a FC. Further research is needed to understand how to best utilize FCs and less formal conversations.

Neurally adjusted ventilatory assist vs pressure support ventilation in infants recovering from severe acute respiratory distress syndrome: Nested study

ObjectiveNeurally adjusted ventilatory assist (NAVA) is a new ventilator modality with an innovative synchronization technique. Our aim is to verify if NAVA is feasible and safe in terms of physiological and clinical variables in infants recovering from severe acute respiratory distress syndrome (ARDS). DesignThis is a pilot nested study to help future trial design. SettingThe study was performed in third-level academic pediatric intensive care units. PatientsInfants affected by severe ARDS requiring high-frequency ventilation and weaned with NAVA during 2010 were included. Controls (2:1 ratio) were ARDS infants weaned with pressure support ventilation (PSV) during 2008-2009 matched for age, gas exchange impairment, and weight. Main outcome measuresThe main outcome measures were the physiological and ventilator parameters and the duration of ventilator support in PSV or NAVA. ResultsTen infants treated with NAVA and 20 with PSV were studied. Heart rate (P < .001) and mean arterial pressure (P < .001) increased less during NAVA than during PSV. Similarly, Pao2/Fio2 ratio decreased less in NAVA than in PSV (P < .001). Neurally adjusted ventilatory assist also resulted in lower Paco2 (P < .001) and peak pressure (P = .001), as well as higher minute ventilation (P = .013). COMFORT score (P = .004) and duration of support were lower in NAVA than in PSV (P = .011). ConclusionsNeurally adjusted ventilatory assist is safe and suitable in infants recovering from severe ARDS. It could provide better results than PSV and is worth to be investigated in a multicenter randomized trial.

Success Rates of Pediatric Orotracheal Intubation by Trainees

In a prospective observational study at 15 academic pediatric intensive care units (PICUs), investigators evaluated first-attempt and overall success

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Introduction: Focused bedside ultrasonography (BUS) has been shown to improve acute management of critically ill patients. Limited data are available supporting use of BUS in a tertiary pediatric intensive care unit (PICU) setting. Hypothesis: Implementation of a BUS education program in an academic PICU is feasible. Non-procedural BUS for intravascular fluid status and cardiac function (FC) evaluation would affect clinical management more frequently compared to other core applications. Methods: BUS education for PICU fellows and attending physicians was developed and implemented. The curriculum consisted of a 2 days hands-on course followed by BUS image review by peer practitioners and BUS experts (bi-weekly in PICU and weekly at adult Emergency Medicine BUS rounds). Participants are required to perform BUS studies in the following core applications: procedural (P), FC, thoracic (T), and abdominal (A). BUS clips with clinical scenarios were assessed by two reviewers to determine whether the BUS affected management (critical). Descriptive statistics of categorical variables are compared using Fisher’s exact test with p-value<0.05 as significant. Results: 13 critical care faculty and 3 fellows received BUS training. From January to June 2012, 201 BUS studies were performed: 57(28%) P, 76(38%) FC, 33(16%) A, and 35(17%) T. 24 studies (17% of all non-P) were identified as critical to lead patient care at the bedside. 46%(11/24) of those studies were FC, followed by other core indications (25% A and 29% T). The proportion of critical BUS studies were not significantly different across the indications (FC 11/76[15%] vs A+T 13/68[19%], p=0.51). Examples of critical studies include: diagnosis of cardiac tamponade, identification of pulmonary hypertension, hemodynamic assessment before tracheal intubation, determination of pneumothorax, location of the chest tube and urinary catheter, differentiation of pleural fluid from pulmonary consolidation and assessment of undifferentiated hypotension and hypoxia. Conclusions: Implementation of a BUS education program in an academic PICU is feasible. The utilization of all non-procedural core applications resulted in critical changes in diagnosis and management of PICU patients.

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Introduction: Red cell distribution width (RDW) has been associated with adverse outcomes related to invasive infections in critically ill adults; it is routinely measured as part of the complete blood count, and has potential as an inexpensive and readily available prognostic biomarker in critically ill children. Hypothesis: We hypothesized that RDW is associated with severity of illness and mortality in patients admitted to the pediatric intensive care unit (PICU) with sepsis. Methods: We performed a prospective cohort study of 90 consecutive pediatric patients with severe sepsis or septic shock admitted to an academic PICU from May 2009 to June 2010; 88 patients had a RDW collected within 24 hours of sepsis diagnosis and were included for analysis. We determined the association of RDW with hemoglobin using Spearman’s Rho. Using published data, we categorized RDW? 14.5 as normal, 14.6-16.0 as mildly elevated, and >16.0 as severely elevated. We compared PIM-2 score, ventilator-free days, vasoactive-free days, and PICU LOS as markers of illness severity in RDW groups using the Kruskal-Wallis test. We compared mortality between RDW groups using the?2 test. The area under the ROC curve was used to evaluate the role for initial RDW to determine vital status at PICU discharge. Results: The median (IQR) age was 9 years (1 mo-14 yrs), 43% were male, and 42% were White. The median (IQR) RDW was 15.2 (12.6-17.2). RDW was not correlated with hemoglobin (r=-0.08, p=0.44), supporting that RDW changes were not solely due to anemia. Across normal, mildly elevated, and severely elevated RDW groups, there was no significant difference in PIM-2 (p=0.24), ventilator-free days (p=0.81), vasoactive-free days (p=0.72), or PICU LOS (p=0.98). Mortality was 6/29 (31.6%) in normal, 4/27 (21.1%) in mildly elevated, and 9/32 (47.4%) in severely elevated RDW groups (p=0.46). The AUC for RDW to predict PICU mortality was 0.59 (95% CI, 0.43, 0.76). Conclusions: Unlike in adults, RDW was not associated with severity of illness or mortality in critically ill children with sepsis. More research is needed to determine the significance of RDW in a broader PICU population.

Comparison of the effectiveness and safety of two insulin infusion protocols in the management of hyperglycemia in critically ill children*

To compare the effectiveness and safety of a paper-based and a computerized algorithm used for tight glycemic control. Academic pediatric intensive care unit. Retrospective cohort study. Two groups of nondiabetic critically ill children with persistent hyperglycemia (blood glucose ≥140 mg/dL [ ≥7.8 mmol/L] for at least 2 hrs) were included. One group of patients' blood glucose was controlled at 90-119 mg/dL (5.0-6.6 mmol/L) using the Yale Insulin Infusion Protocol (YIIP), a paper-based protocol. Another group of patients' blood glucose was controlled at 80-110 mg/dL (4.4-6.1 mmol/L) with eProtocol insulin (ePi), a computerized decision support tool. The effectiveness of the protocols was compared using percentages of blood glucose values within target range and glucose variability index. A safety comparison was made using hypoglycemia rates at ≤40 mg/dL (≤2.2 mmol/L), ≤50 mg/dL (≤2.8 mmol/L), and ≤60 mg/dL (≤3.3 mmol/L). Forty-two patients and 12 patients were included in the YIIP and ePi groups, respectively. The percent of values in range was lower in the YIIP group (33%) compared with the ePi group (41%) (p < .001). Mean glucose variability index was comparable in the two groups (18.7 ± 8.9 mg/dL/hr [1.0 ± 0.5 mmol/L/hr] for the YIIP group and 14.4 ± 7.6 mg/dL/hr [0.8 ± 0.4 mmol/L/hr] for the ePi group; p = .111). Hypoglycemia rates were statistically similar in both groups. In the YIIP group, 10% of patients and in the ePi group, 25% of patients had blood glucose ≤40 mg/dL (≤2.2 mmol/L) (p = .168). YIIP is less effective but is as safe as ePi in achieving tight glycemic control. We are awaiting the results of two multicenter trials designed to determine the survival benefit of tight glycemic control in children. Further studies are needed to determine the clinical significance of the different glucose metrics in critically ill patients.

Defining acute lung disease in children with the oxygenation saturation index*

To evaluate whether a formula could be derived using oxygen saturation (Spo2) to replace Pao2 that would allow identification of children with acute lung injury and acute respiratory distress syndrome. Definitions of acute lung injury and acute respiratory distress syndrome require arterial blood gases to determine the Pao2/Fio2 ratio of 300 (acute lung injury) and 200 (acute respiratory distress syndrome). Post hoc data analysis of measurements abstracted from two prospective databases of randomized controlled trials. Academic pediatric intensive care units. A total of 255 children enrolled in two large prospective trials of therapeutic intervention for acute lung disease: calfactant and prone positioning. Data were abstracted including Pao2, Paco2, pH, Fio2, and mean airway pressure. Repeated-measures analyses, using linear mixed-effects models, were used to build separate prediction equations for the Spo2/Fio2 ratio, oxygenation index [(Fio2 x Mean Airway Pressure)/Pao2], and oxygen saturation index [(Fio2 x Mean Airway Pressure)/Spo2 ]. A generalization of R was used to measure goodness-of-fit. Generalized estimating equations with a logit link were used to calculate the sensitivity and specificity for the cutoffs of Pao2/Fio2 ratio of 200 and 300 and equivalent values of Spo2/Fio2 ratio, oxygenation index, and oxygen saturation index. An Spo2/Fio2 ratio of 253 and 212 would equal criteria for acute lung injury and acute respiratory distress syndrome, respectively. An oxygenation index of 5.3 would equal acute lung injury criteria, and an oxygenation index of 8.1 would qualify for acute respiratory distress syndrome. An oxygen saturation index, which includes the mean airway pressure and the noninvasive measure of oxygenation, of 6.5 would be equivalent to the acute lung injury criteria, and an oxygen saturation index of 7.8 would equal acute respiratory distress syndrome criteria. Noninvasive methods of assessing oxygenation may be utilized with reasonable sensitivity and specificity to define acute lung injury and acute respiratory distress syndrome, and, with prospective validation, have the potential to increase the number of children enrolled into clinical trials.