Neal Patel

Extubation failure in pediatric intensive care: A multiple-center study of risk factors and outcomes

ObjectiveTo determine a contemporary failed extubation rate, risk factors, and consequences of extubation failure in pediatric intensive care units (PICUs). Three hypotheses were investigated: a) Extubation failure is in part disease specific; b) preexisting respiratory conditions predispose to extubation failure; and c) admission acuity scoring does not affect extubation failure. DesignTwelve-month prospective, observational, clinical study. SettingSixteen diverse PICUs in the United States. PatientsPatients were 2,794 patients from the newborn period to 18 yrs of age experiencing a planned extubation trial. InterventionsNone. Measurements and Main ResultsA descriptive statistical analysis was performed, and outcome differences of the failed extubation population were determined. The extubation failure rate was 6.2% (174 of 2,794; 95% confidence interval, 5.3–7.1). Patient features associated with extubation failure (p < .05) included age ≤24 months; dysgenetic condition; syndromic condition; chronic respiratory disorder; chronic neurologic condition; medical or surgical airway condition; chronic noninvasive positive pressure ventilation; the need to replace the endotracheal tube on admission to the PICU; and the use of racemic epinephrine, steroids, helium-oxygen therapy (heliox), or noninvasive positive pressure ventilation within 24 hrs of extubation. Patients failing extubation had longer pre-extubation intubation time (failed, 148.7 hrs, sd ± 207.8 vs. success, 107.9 hrs, sd ± 171.3; p < .001), longer PICU length of stay (17.5 days, sd ± 15.6 vs. 7.6 days, sd ± 11.1; p < .001), and a higher mortality rate than patients not failing extubation (4.0% vs. 0.8%; p < .001). Failure was found to be in part disease specific, and preexisting respiratory conditions were found to predispose to failure whereas admission acuity did not. ConclusionA variety of patient features are associated with an increase in extubation failure rate, and serious outcome consequences characterize the extubation failure population in PICUs.

Genetic variants of GSNOR and ADRB2 influence response to albuterol in African-American children with severe asthma

African Americans are disproportionately affected by asthma. Social and economic factors play a role in this disparity, but there is evidence that genetic factors may also influence the development of asthma and response to therapy in African American children. Our hypothesis is that variations in asthma related genes contribute to the observed asthma disparities by influencing the response to asthma‐specific therapy. In order to test this hypothesis, we characterized the clinical response to asthma‐specific therapy in 107 African American children who presented to the emergency room in status asthmaticus, with a primary outcome indicator of length of time on continuous albuterol. Single locus analysis indicated that genotype variation in glutathione‐dependent S‐nitrosoglutathione reductase (GSNOR) is associated with a decreased response to asthma treatment in African American children. A post hoc multi‐locus analysis revealed that a combination of four single nucleotide polymorphisms (SNPs) within GSNOR, adrenergic receptor beta 2, and carbamoyl phosphate synthetase‐1 give a 70% predictive value for lack of response to therapy. This predictive model needs replication in other cohorts of patients with asthma, but suggests gene–gene interactions may have greater significance than that identified with single variants. Our findings also suggest that genetic variants may contribute to the observed population disparities in asthma. Pediatr Pulmonol. 2009; 44:649–654.

Effect of inhaled nitric oxide on respiratory mechanics in ventilated infants with RSV bronchiolitis

Objective: To evaluate the bronchodilator effect of inhaled nitric oxide (NO) in infants with respiratory failure caused by respiratory syncytial virus (RSV) bronchiolitis and to compare the effect with the one obtained by salbutamol. Design: Prospective study. Setting: Pediatric intensive care unit of a university childrens hospital. Patients: Twelve acutely ill, intubated infants (mean age 4.5 months, mean weight 4.9 kg) with respiratory failure due to documented RSV bronchiolitis. Interventions: Total respiratory system resistance (Rrs) was measured by single breath occlusion at the baseline and after inhaling NO at 20, 40 and 60 ppm for 1 h, and after inhalation of a standard β2-agonist, salbutamol. Arterial blood gas analysis was performed at each study level on 6 of the 12 patients. Results: The baseline mean Rrs (SE) was 0.29 (0.04) cm H2O/ml per s. At each dose of NO, the mean Rrs (SE) was 0.28 (0.04) cm H2O/ml per s. With salbutamol, the mean Rrs (SE) was 0.21 (0.03) cm H2O/ml per s. These values were not significantly different from each other (by ANOVA). Inhaled NO produced a significant decrease in Rrs of greater than 4 times the coefficient of variation of the baseline measurement in 3 of 12 patients. Seven of 12 patients had no significant change while two patients had a significant increase in Rrs. Inhaled salbutamol produced a significant decrease in Rrs in 5 of 11 patients, while 6 showed no change in Rrs. Conclusion: Inhaled NO has no apparent bronchodilator effect in the majority of acutely ill infants with RSV bronchiolitis and does not appear to provide any additional benefit over the use of salbutamol. The clinical benefit of inhaled NO as a bronchodilator is questionable under these conditions.

Effects of mental demands during dispensing on perceived medication safety and employee well being: A study of workload in pediatric hospital pharmacies

BACKGROUND Pharmacy workload is a modifiable work system factor believed to affect both medication safety outcomes and employee outcomes, such as job satisfaction. OBJECTIVES This study sought to measure the effect of workload on safety and employee outcomes in 2 pediatric hospitals and to do so using a novel approach to pharmacy workload measurement. METHODS Rather than measuring prescription volume or other similar indicators, this study measured the type and intensity of mental demands experienced during the medication dispensing tasks. The effects of external (interruptions, divided attention, and rushing) and internal (concentration and effort) task demands on perceived medication error likelihood, adverse drug event likelihood, job dissatisfaction, and burnout were statistically estimated using multiple linear and logistic regression. RESULTS Pharmacists and pharmacy technicians reported high levels of external and internal mental demands during dispensing. The study supported the hypothesis that external demands (interruptions, divided attention, and rushing) negatively impacted medication safety and employee well-being outcomes. However, as hypothesized, increasing levels of internal demands (concentration and effort) were not associated with greater perceived likelihood of error, adverse drug events, or burnout and even had a positive effect on job satisfaction. CONCLUSIONS Replicating a prior study in nursing, this study shows that new conceptualizations and measures of workload can generate important new findings about both detrimental and beneficial effects of workload on patient safety and employee well-being. This study discusses what those findings imply for policy, management, and design concerning automation, cognition, and staffing.

Modified Norwood operation for hypoplastic left heart syndrome

BACKGROUND We examined early results in infants with hypoplastic left heart syndrome undergoing the Norwood operation with perioperative use of inhaled nitric oxide and application of extracorporeal membrane oxygenation. METHODS Medical records were reviewed retrospectively. RESULTS Between April 1997 and March 2001, 50 infants underwent a modified Norwood operation for hypoplastic left heart syndrome. Mean age at operation was 7.5 +/- 5.7 days, and mean weight was 3.1 +/- 0.5 kg. Five infants had a delayed operation because of sepsis. The mean diameter of the ascending aorta by echocardiography was 3.6 +/- 1.8 mm. Ductal cannulation was used to establish cardiopulmonary bypass in all patients. Mean circulatory arrest time was 39.4 +/- 4.8 minutes. The size of the pulmonary-systemic shunt was 3.0 mm in 6 infants, 3.5 mm in 37, and 4.0 mm in 7. Infants with persistent hypoxia (partial pressure of oxygen < 30 mm Hg) received nitric oxide after they were weaned from cardiopulmonary bypass. Extracorporeal membrane oxygenation was initiated in 8 infants in the pediatric intensive care unit primarily for low cardiac output and in 8 in the operating room because of the inability to separate them from cardiopulmonary bypass. The 30-day mortality rate was 22% (11 of 50 patients), and the hospital mortality rate was 32% (16 of 50 patients). Mean follow-up was 17 months. Ten patients (20%) underwent stage-two repair, with one operative death. One survivor had a Fontan procedure, and 2 underwent heart transplantation, with one death. CONCLUSIONS Early application of extracorporeal membrane oxygenation for hemodynamic instability and selective use of nitric oxide for persistent hypoxia in the immediate postoperative period may improve survival of patients with hypoplastic left heart syndrome. Renal failure requiring hemofiltration during extracorporeal membrane oxygenation (p < 0.05) and cardiopulmonary arrest in the pediatric intensive care unit (p < 0.05) were predictors of hospital mortality.

Methemoglobinemia: Toxicity of inhaled nitric oxide therapy.

Elevation in methemoglobin is a known toxicity of inhaled nitric oxide (NO) therapy. This article describes two significant episodes of methemoglobinemia. These cases illustrate the probable cause and the treatment strategies for the potential for delivery of high concentrations of NO, resulting in methemoglobinemia with moderate and even low-dose delivered NO. We propose mechanisms for this occurrence and means of prevention.

Code status and resuscitation options in the electronic health record

AIM The advance discussion and documentation of code-status is important in preventing undesired cardiopulmonary resuscitation and related end of life interventions. Code-status documentation remains infrequent and paper-based, which limits its usefulness. This study evaluates a tool to document code-status in the electronic health records at a large teaching hospital, and analyzes the corresponding data. METHODS Encounter data for patients admitted to the Medical Center were collected over a period of 12 months (01-APR-2012-31-MAR-2013) and the code-status attribute was tracked for individual patients. The code-status data were analyzed separately for adult and pediatric patient populations. We considered 131,399 encounters for 83,248 adult patients and 80,778 encounters for 55,656 pediatric patients in this study. RESULTS 71% of the adult patients and 30% of the pediatric patients studied had a documented code-status. Age and severity of illness influenced the decision to document code-status. Demographics such as gender, race, ethnicity, and proximity of primary residence were also associated with the documentation of code-status. CONCLUSION Absence of a recorded code-status may result in unnecessary interventions. Code-status in paper charts may be difficult to access in cardiopulmonary arrest situations and may result in unnecessary and unwanted interventions and procedures. Documentation of code-status in electronic records creates a readily available reference for care providers.

PROTOCOL VIOLATIONS DURING MEDICATION ADMINISTRATION IN PEDIATRICS

The paper uses a new measure of protocol violations to explore the extent of violations in the medication administration process. 203 nurses in three units of a free-standing pediatric hospital were provided with a survey assessing violations in the medication administration process; 120 nurses responded for a response rate of 59%. Violation data were collected for three stages of the medication administration process: matching medications to the medication administration record, checking patient identification, and documenting administration. The percentage of nurses who reported violating protocol in the medication administration process ranged from 8.4% to 30.2% in routine situations, and from 32.2% to 53.0% in emergency situations. Violations in the medication administration process may lead to medication errors. To improve medication safety, efforts should be taken to discover the system deficiencies that produce such frequent violations. System redesign should then address these deficiencies.

Nursing Workload and its Effect on Patient and Employee Safety

A well accepted human factors concept is that poorly designed work systems can produce workload levels that pose a threat to safety and performance. The purpose of this study was to assess a systems model of workload and safety developed for nursing/healthcare. Using survey data from six nursing units in two pediatric hospitals, the study measured the relationship between self-reported workload at the unit, job, and task levels on the one hand and job dissatisfaction, burnout, and medication error likelihood on the other. Multiple linear and logistic regression revealed that staffing adequacy and medication administration workload strongly predicted the above patient and employee safety outcomes. Design priorities and strategies for future research are discussed, including the need for multiple-level approaches.

A Retrospective Characterization of African-and European American Asthmatic Children in a Pediatric Critical Care Unit

OBJECTIVE To determine if African American and European American children with asthma admitted to an intensive care unit (ICU) had different characteristics, we conducted a retrospective chart review of asthma admissions to the regions only pediatric ICU. PATIENTS AND METHODS A chart review was performed on 125 patients with asthma admitted to the pediatric critical care unit at Vanderbilt Childrens Hospital. Descriptive statistics, clinical characteristics, and disparities in care were compared using either Fishers exact tests or Wilcoxon ranksum tests. RESULTS Most of the children reported previous admissions to a pediatric ICU (63%) or a hospital (82%) for asthma. Despite this, only 48% of the children were taking inhaled corticosteroids before admission. Only 28% of the children reported being followed by an asthma specialist, but, of these, 97% were taking corticosteroids. There were no racial/ethnic disparities in medication use, treatment, or outcomes. CONCLUSION We found no racial/ethnic disparities in inpatient/outpatient medication usage, treatment, or outcomes between African American and European American children in our cohort. Recurrent admissions to the ICU among children with severe asthma are common, and inhaled corticosteroids usage is relatively low. Asthmatic children with ICU admissions should be followed and treated aggressively by an asthma specialist.