Vicki L. Montgomery

Impact of multiple organ system dysfunction and nosocomial infections on survival of children treated with extracorporeal membrane oxygenation after heart surgery

Objectives: To evaluate whether cardiac and noncardiac variables may be used to predict survival in children treated with extracorporeal membrane oxygenation (ECMO) after cardiopulmonary bypass and to determine when to discontinue ECMO support. Design: Retrospective review. Setting: Neonatal and pediatric intensive care units of Kosair Childrens Hospital. Patients: Fifty‐nine children treated with ECMO after cardiopulmonary bypass from 1987 through 1996. Interventions: None. Measurements and Main Results: Medical, nursing, operative, and perfusion records for each patient were reviewed. The primary outcome measure was survival to hospital discharge. Cardiac and noncardiac variables were recorded at serial times. Nineteen of 59 patients (32%) survived. No cardiac variable was a clinically useful predictor of survival or marker for when to discontinue ECMO. Among the noncardiac variables, progressive multiple organ system dysfunction and development of a nosocomial infection were significantly associated with nonsurvival. No patient with a positive blood culture (n = 3) within the first 24 hrs of ECMO survived, and 21 of 24 children with a positive culture from any site during ECMO died (p = .007). Despite their higher mortality, children with positive cultures were supported with ECMO significantly longer than those with negative cultures (275 ± 168 vs. 135 ± 108 hrs, respectively; p = .0004). For all patients, the longest duration of ECMO that resulted in survival was 256 hrs. For children with a positive culture, the longest duration of support that resulted in survival was 200 hrs. Conclusions: Support with ECMO beyond 256 hrs was not associated with survival. Progressive multiple organ system dysfunction and nosocomial infections have a negative impact on survival. Serious consideration should be given to discontinuing ECMO support whenever there is a progressive increase in the number of abnormally functioning organ systems, a nosocomial infection occurs, or native cardiac function has not improved significantly by 250 hrs of ECMO support.

Effect of fatigue, workload, and environment on patient safety in the pediatric intensive care unit.

Introduction: Pediatric intensive care unit patient care occurs in an unpredictable, technology-rich environment that is dependent on highly skilled providers who need constant communication—all features providing the setting for potential error. This review examines basic principles of human error and sleep physiology and evaluates the evidence for potential effects of fatigued healthcare workers and workload on medical error. Body: The pediatric intensive care unit setting, examined from a human factors engineering standpoint, is a highly complex environment in which fatigue and excessive workload can provide potential “holes” that may allow errors to occur. A large body of evidence is examined that suggests sleep deprivation can impair medical and surgical performance and can be improved with scheduling intervention. Nursing fatigue and workload have documented effects on increasing intensive care unit error, infections, and cost. Specific environmental factors such as distractions and communication barriers are also associated with greater error. Conclusion: Fatigue, excessive workload, and the pediatric intensive care unit environment can adversely affect the performance of physicians and nurses working in the pediatric intensive care unit. The weight of the evidence suggests that these factors have the potential to contribute to medical error in the pediatric intensive care unit.

Guidelines for the determination of brain death in infants and children: An update of the 1987 Task Force recommendations

Objective:To review and revise the 1987 pediatric brain death guidelines. Methods:Relevant literature was reviewed. Recommendations were developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. Conclusions and Recommendations:1) Determination of brain death in term newborns, infants, and children is a clinical diagnosis based on the absence of neurologic function with a known irreversible cause of coma. Because of insufficient data in the literature, recommendations for preterm infants <37 wks gestational age are not included in this guideline. 2) Hypotension, hypothermia, and metabolic disturbances should be treated and corrected and medications that can interfere with the neurologic examination and apnea testing should be discontinued allowing for adequate clearance before proceeding with these evaluations. 3) Two examinations, including apnea testing with each examination separated by an observation period, are required. Examinations should be performed by different attending physicians. Apnea testing may be performed by the same physician. An observation period of 24 hrs for term newborns (37 wks gestational age) to 30 days of age and 12 hrs for infants and children (>30 days to 18 yrs) is recommended. The first examination determines the child has met the accepted neurologic examination criteria for brain death. The second examination confirms brain death based on an unchanged and irreversible condition. Assessment of neurologic function after cardiopulmonary resuscitation or other severe acute brain injuries should be deferred for ≥24 hrs if there are concerns or inconsistencies in the examination. 4) Apnea testing to support the diagnosis of brain death must be performed safely and requires documentation of an arterial Paco2 20 mm Hg above the baseline and ≥60 mm Hg with no respiratory effort during the testing period. If the apnea test cannot be safely completed, an ancillary study should be performed. 5) Ancillary studies (electroencephalogram and radionuclide cerebral blood flow) are not required to establish brain death and are not a substitute for the neurologic examination. Ancillary studies may be used to assist the clinician in making the diagnosis of brain death a) when components of the examination or apnea testing cannot be completed safely as a result of the underlying medical condition of the patient; b) if there is uncertainty about the results of the neurologic examination; c) if a medication effect may be present; or d) to reduce the interexamination observation period. When ancillary studies are used, a second clinical examination and apnea test should be performed and components that can be completed must remain consistent with brain death. In this instance, the observation interval may be shortened and the second neurologic examination and apnea test (or all components that are able to be completed safely) can be performed at any time thereafter. 6) Death is declared when these criteria are fulfilled.

Critical care delivery: The importance of process of care and ICU structure to improved outcomes: An update from the American college of critical care medicine task force on models of critical care

In 2001, the Society of Critical Care Medicine published practice model guidelines that focused on the delivery of critical care and the roles of different ICU team members. An exhaustive review of the additional literature published since the last guideline has demonstrated that both the structure and process of care in the ICU are important for achieving optimal patient outcomes. Since the publication of the original guideline, several authorities have recognized that improvements in the processes of care, ICU structure, and the use of quality improvement science methodologies can beneficially impact patient outcomes and reduce costs. Herein, we summarize findings of the American College of Critical Care Medicine Task Force on Models of Critical Care: 1) An intensivist-led, high-performing, multidisciplinary team dedicated to the ICU is an integral part of effective care delivery; 2) Process improvement is the backbone of achieving high-quality ICU outcomes; 3) Standardized protocols including care bundles and order sets to facilitate measurable processes and outcomes should be used and further developed in the ICU setting; and 4) Institutional support for comprehensive quality improvement programs as well as tele-ICU programs should be provided.

Comparison of end-tidal CO2 and Paco2 in children receiving mechanical ventilation.

Objective To determine whether end-tidal CO2 (Petco2) measurement provides a reliable estimate of ventilation in critically ill children who are mechanically ventilated. Design Prospective, nonrandomized, consecutive enrollment study. Setting A university-affiliated children’s hospital pediatric intensive care unit. Patients All intubated, mechanically ventilated pediatric patients. Interventions All Petco2-Paco2 pairs were from patients ventilated with a Servo 300 Ventilator (Siemens-Elema AB, Stockholm, Sweden). When a blood gas sample was obtained, Petco2 as measured by a continuous mainstream Petco2 capnograph was recorded. Measurements The results of blood gas measurements and corresponding Petco2 measurements were recorded. Demographic data and primary diagnosis were noted. Petco2-Paco2 pairs obtained from patients with intracardiac shunts or obtained during high-frequency oscillation or extracorporeal membrane oxygenation at the time of measurement were excluded from analysis. Linear regression was used to analyze Petco2-Paco2 pairs. Repeated measure analysis of variance with the mixed-model algorithm in SAS software (SAS Institute, Carey, NC) was used to analyze the trend in the Petco2 and Paco2 relationship. Chi-square was used to analyze categorical data. Statistical significance was considered p < .05. Results A total of 129 children were enrolled, and 1708 paired Paco2 and Petco2 measurements were recorded. The mean age ± sd was 4.1 ± 5.6 yrs. Paco2 positively correlated with Petco2. The linear equation for the regression analysis was y = 0.71 x (95% confidence interval, 0.69–0.73) + 8.93 (95% confidence interval, 7.89–9.97), with r2 = .716 and p < .001. The Petco2-Paco2 difference was ≤5 mm Hg (0.67 kPa) in 54% and ≤10 mm Hg (1.33 kPa) in 80% of paired data. Increased lung disease had a negative effect on Petco2 correlation with Paco2. A total of 223 of 640 (35%) blood gases (defined by Pao2/Fio2 ratio of <200) had >10 mm Hg (1.33 kPa) difference between the Petco2 and Paco2. However, only 111 of 1068 (10%) Petco2-Paco2 pairs had a difference of >10 mm Hg (1.33 kPa) in patients with a Pao2/Fio2 ratio >200. Trend analysis showed the Petco2-Paco2 difference increased with increasing duration of mechanical ventilation. Conclusion In most intubated, mechanically ventilated infants and children, Petco2 reliably estimates ventilation.

Integrated In-situ Simulation Using Redirected Faculty Educational Time to Minimize Costs: A Feasibility Study

Introduction: Simulation is an effective teaching tool, but many hospitals do not possess the space or finances to support traditional simulation centers. Our objective is to describe the feasibility of an in situ simulation program model that uses minimal permanent space and “redirected” cost-neutral faculty educational time to address these issues. Methods: Two pediatric simulators and audiovisual equipment were purchased. Course faculty were derived from a group of physicians and nurses with a percentage work assignment apportioned to education. A portion of this was subsequently redirected toward simulation. After 2 years of operation, faculty were surveyed regarding time devoted to the program. Program growth and quality statistics were examined descriptively. Results: The program supported 786 learner encounters in 166 sessions over 2 years. Simulation hours per month increased over sixfold during that period (P < 0.001). Program initiation cost was

Site-level variance for adverse tracheal intubation-associated events across 15 North American PICUs: a report from the national emergency airway registry for children*.

128920.89, with subsequent yearly costs of

Prognostic value of pre- and postoperative cardiac troponin I measurement in children having cardiac surgery.

11,695. Mean program ratings ranged between 4.5/5 for Crisis Resource Management and 4.4/5 for communication skills training. Resident (2.6 h/y increase, P value <0.001) and nursing (2.2 h/y increase, P < 0.001) simulation hours increased significantly. Faculty involvement averaged between 3% and 32% of total work hours. Conclusion: This report demonstrates the feasibility of implementing an in situ simulation program using minimal permanent institutional space and cost-neutral redirected faculty time. This type of programmatic structure is conducive to short- and medium-term growth, is well received by participants, and allows for substantial cost savings. Future work will be needed to determine what growth limitations are inherent in this staffing and structural model.

Low-dose β-agonist continuous nebulization therapy for status asthmaticus in children

Objective: Tracheal intubation in PICUs is associated with adverse tracheal intubation–associated events. Patient, provider, and practice factors have been associated with tracheal intubation–associated events; however, site-level variance and the association of site-level characteristics on tracheal intubation–associated event outcomes are unknown. We hypothesize that site-level variance exists in the prevalence of tracheal intubation–associated events and that site characteristics may affect outcomes. Design: Prospective observational cohort study. Setting: Fifteen PICUs in North America. Subjects: Critically ill pediatric patients requiring tracheal intubation. Interventions: None. Measurement and Main Results: Tracheal intubation quality improvement data were collected in 15 PICUs from July 2010 to December 2011 using a National Emergency Airway Registry for Children with robust site-specific compliance. Tracheal intubation–associated events and severe tracheal intubation–associated events were explicitly defined a priori. We analyzed the association of site-level variance with tracheal intubation–associated events using univariate analysis and adjusted for previously identified patient- and provider-level risk factors. Analysis of 1,720 consecutive intubations revealed an overall prevalence of 20% tracheal intubation–associated events and 6.5% severe tracheal intubation–associated events, with considerable site variability ranging from 0% to 44% tracheal intubation–associated events and from 0% to 20% severe tracheal intubation–associated events. Larger PICU size (> 26 beds) was associated with fewer tracheal intubation–associated events (18% vs 23%, p = 0.006), but the presence of a fellowship program was not (20% vs 18%, p = 0.58). After adjusting for patient and provider characteristics, both PICU size and fellowship presence were not associated with tracheal intubation–associated events (p = 0.44 and p = 0.18, respectively). Presence of mixed ICU with cardiac surgery was independently associated with a higher prevalence of tracheal intubation–associated events (25% vs 15%; p < 0.001; adjusted odds ratio, 1.81; 95% CI, 1.29–2.53; p = 0.01). Substantial site-level variance was observed in medication use, which was not explained by patient characteristic differences. Conclusions: Substantial site-level variance exists in tracheal intubation practice, tracheal intubation–associated events, and severe tracheal intubation–associated events. Neither PICU size nor fellowship training program explained site-level variance. Interventions to reduce tracheal intubation–associated event prevalence and severity will likely need to be contextualized to variability in individual ICUs patients, providers, and practice.

Development of a Quality Improvement Bundle to Reduce Tracheal Intubation–Associated Events in Pediatric ICUs

ABSTRACT The objective of this study was to determine if perioperative elevation of cardiac troponin I (cTnI) predicts mortality in infants and children after surgical correction of congenital heart defects. One hundred infants and children having open heart surgery were studied. Blood samples for cTnI analysis were collected before cardiopulmonary bypass (CPB) and at 4, 8, 12, and 24 h after initiation of CPB. Demographic information, cardiac defect, repair performed, duration of CPB, complications, and outcome were recorded. Cardiac defects were categorized as atrial septal defect (ASD), ventricular septal defect (VSD), hypoplastic left heart syndrome (HLHS), complex, and “other.” Baseline cTnI was significantly lower in survivors (mean 0.42 ng/ml, median 0.35 ng/ml) than in nonsurvivors (mean 1.89, median 1.30), p= 0.0001. Baseline cTnI was significantly higher in the HLHS group (mean 1.47, median 1.10) than in all other subgroups (mean 0.62, median 0.35), p≤ 0.009. There were no significant differences between survivors and nonsurvivors at the remaining sampling times. Children who died from cardiac failure (n = 2) were more likely to have 4 h cTnI >125 ng/ml compared to survivors (2 of 90). Within cardiac defect subgroups, 4 h cTnI was significantly higher in the complex group (mean = 53.51, median = 32.30) than in the ASD (mean = 23.84, median = 19.85) and other (mean = 21.59, median 21.50) subgroups. Perioperative measurement of cTnI identifies children within specific cardiac defect subgroups at risk of mortality after cardiac surgery. We speculate that detection of myocardial injury may decrease mortality and morbidity in children with complicated congenital cardiac lesions by leading to improvements in perioperative management.