Lower-Dose, Intravenous Chlorothiazide Is an Effective Adjunct Diuretic to Furosemide Following Pediatric Cardiac Surgery.

OBJECTIVES: Postoperative fluid overload is ubiquitous in neonates and infants following operative intervention for congenital heart defects; ineffective diuresis is associated with poor outcomes. Diuresis with furosemide is widely used, yet there is often resistance at higher doses. In theory, furosemide resistance may be overcome with chlorothiazide; however, its efficacy is unclear, especially in lower doses and in this population. We hypothesized the addition of lower-dose, intravenous chlorothiazide following surgery in patients on high-dose furosemide would induce meaningful diuresis with minimal side effects. METHODS: This was a retrospective, cohort study. Postoperative infants younger than 6 months, receiving high-dose furosemide, and given lower-dose chlorothiazide (1-2 mg/kg every 6-12 hours) were identified. Diuretic doses, urine output, fluid balance, vasoactive-inotropic scores, total fluid intake, and electrolyte levels were recorded. RESULTS: There were 73 patients included. The addition of lower-dose chlorothiazide was associated with a significant increase in urine output (3.8 ± 0.18 vs 5.6 ± 0.27 mL/kg/hr, p < 0.001), more negative fluid balance (16.1 ± 4.2 vs -25.0 ± 6.3 mL/kg/day, p < 0.001), and marginal changes in electrolytes. Multivariate analysis was performed, demonstrating that increased urine output and more negative fluid balance were independently associated with addition of chlorothiazide. Subgroup analysis of 21 patients without a change in furosemide dose demonstrated the addition of chlorothiazide significantly increased urine output (p = 0.03) and reduced fluid balance (p < 0.01), further validating the adjunct effects of chlorothiazide. CONCLUSION: Lower-dose, intravenous chlorothiazide is an effective adjunct treatment in postoperative neonates and infants younger than 6 months following cardiothoracic surgery.

Safety, Efficacy, and Timeliness of Intravenous Potassium Chloride Replacement Protocols in a Pediatric Cardiothoracic Intensive Care Unit.

OBJECTIVE: Hypokalemia in children following cardiac surgery occurs frequently, placing them at risk of life-threatening arrhythmias. However, renal insufficiency after cardiopulmonary bypass warrants careful administration of potassium (K+). Two different nurse-driven protocols (high dose and tiered dosing) were implemented to identify an optimal K+ replacement regimen, compared to an historical low-dose protocol. Our objective was to evaluate the safety, efficacy, and timeliness of these protocols. DESIGN: A retrospective cohort review of pediatric patients placed on intravenous K+ replacement protocols over 1 year was used to determine efficacy and safety of the protocols. A prospective single-blinded review of K+ repletion was used to determine timeliness. PATIENTS: Pediatric patients with congenital or acquired cardiac disease. SETTING: Twenty-four-bed cardiothoracic intensive care unit in a tertiary children's hospital. INTERVENTIONS: Efficacy was defined as fewer supplemental potassium chloride (KCl) doses, as well as a higher protocol to total doses ratio per patient. Safety was defined as a lower percentage of serum K+ levels ≥4.8 mEq/L after a dose of KCl. Between-group differences were assessed by nonparametric univariate analysis. RESULTS: There were 138 patients with a median age of 3.0 (interquartile range: 0.23-10.0) months. The incidence of K+ levels ≥4.8 mEq/L after a protocol dose was higher in the high-dose protocol versus the tiered-dosing protocol but not different between the low-dose and tiered-dosing protocols (high dose = 2.2% vs tiered dosing = 0.5%, P = .05). The ratio of protocol doses to total doses per patient was lower in the low-dose protocol compared to the tiered-dosing protocol (P < .05). Protocol doses were administered 45 minutes faster (P < .001). CONCLUSION: The tiered-dosed, nurse-driven K+ replacement protocol was associated with decreased supplemental K+ doses without increased risk of hyperkalemia, administering doses faster than individually ordered doses; the protocol was effective, safe, and timely in the treatment of hypokalemia in pediatric patients after cardiac surgery.

An ensemble boosting model for predicting transfer to the pediatric intensive care unit.

BACKGROUND: Early deterioration indicators have the potential to alert hospital care staff in advance of adverse events, such as patients requiring an increased level of care, or the need for rapid response teams to be called. Our work focuses on the problem of predicting the transfer of pediatric patients from the general ward of a hospital to the pediatric intensive care unit. OBJECTIVES: The development of a data-driven pediatric early deterioration indicator for use by clinicians with the purpose of predicting encounters where transfer from the general ward to the PICU is likely. METHODS: Using data collected over 5.5 years from the electronic health records of two medical facilities, we develop machine learning classifiers based on adaptive boosting and gradient tree boosting. We further combine these learned classifiers into an ensemble model and compare its performance to a modified pediatric early warning score (PEWS) baseline that relies on expert defined guidelines. To gauge model generalizability, we perform an inter-facility evaluation where we train our algorithm on data from one facility and perform evaluation on a hidden test dataset from a separate facility. RESULTS: We show that improvements are witnessed over the modified PEWS baseline in accuracy (0.77 vs. 0.69), sensitivity (0.80 vs. 0.68), specificity (0.74 vs. 0.70) and AUROC (0.85 vs. 0.73). CONCLUSIONS: Data-driven, machine learning algorithms can improve PICU transfer prediction accuracy compared to expertly defined systems, such as a modified PEWS, but care must be taken in the training of such approaches to avoid inadvertently introducing bias into the outcomes of these systems.

Psychometric evaluation of a modified version of the family satisfaction in the ICU survey in parents/caregivers of critically ill children*.

OBJECTIVES: The Family Satisfaction in the Intensive Care Unit 24 (FS-ICU 24) survey consists of two domains (overall care and medical decision-making) and was validated only for family members of adult patients in the ICU. The purpose of this study was to evaluate the internal consistency and construct validity of the FS-ICU 24 survey modified for parents/caregivers of pediatric patients (Pediatric Family Satisfaction in the Intensive Care Unit 24 [pFS-ICU 24]) by comparing it to McPherson's PICU satisfaction survey, in a similar racial/ethnic population as the original Family Satisfaction in the Intensive Care Unit validation studies (English-speaking Caucasian adults). We hypothesized that the pFS-ICU 24 would be psychometrically sound to assess satisfaction of parents/caregivers with critically ill children. DESIGN: A prospective survey examination of the pFS-ICU 24 was performed (1/2011-12/2011). Participants completed the pFS-ICU 24 and McPherson's survey with the order of administration alternated with each consecutive participant to control for order effects (nonrandomized). Cronbach's alphas (α) were calculated to examine internal consistency reliability, and Pearson correlations were calculated to examine construct validity. SETTING: University-affiliated, children's hospital, cardiothoracic ICU. SUBJECTS: English-speaking Caucasian parents/caregivers of children less than 18 years old admitted to the ICU (on hospital day 3 or 4) were approached to participate if they were at the bedside for greater than or equal to 2 days. MEASUREMENTS AND MAIN RESULTS: Fifty parents/caregivers completed the surveys (mean age ± SD = 36.2±9.6 yr; 56% mothers). The α for the pFS-ICU 24 was 0.95 and 0.92 for McPherson's survey. Overall, responses for the pFS-ICU 24 and McPherson's survey were significantly correlated (r = 0.73; p < 0.01). The average overall pFS-ICU 24 satisfaction score was 92.6 ± 8.3. The average pFS-ICU 24 satisfaction with care domain and medical decision-making domain scores were 93.3 ± 8.8 and 91.2 ± 8.9, respectively. CONCLUSIONS: The pFS-ICU 24 is a psychometrically sound measure of satisfaction with care and medical decision-making of parents/caregivers with children in the ICU.

Race/Ethnicity is not associated with mortality in the PICU.

OBJECTIVE: To determine if a difference in survival exists between children of different racial/ethnic groups who were admitted to the PICU, after controlling for severity of illness (pediatric index of mortality 2). METHODS: We used the largest national clinical PICU database (Virtual PICU Performance System) with data from 31 hospitals, from 2005 to 2008. Children 18 years and younger were included. We collected demographic, pediatric index of mortality 2, diagnosis, and PICU mortality data. Logistic regression models were constructed to identify PICU mortality risk factors. RESULTS: The analysis of 80 739 patients revealed that, after controlling for severity of illness, being female (odds ratio [OR]: 1.12 [95% confidence interval (CI): 1.02-1.24] P = .019), 1 month or younger (OR: 1.39 [95% CI: 1.17-1.65] P < .001) or 12 years or older (OR: 1.34 [95% CI: 1.17-1.52] P < .001), or having an infectious diagnosis (OR: 2.22 [95% CI: 1.83-2.71] P < .001) or oncologic diagnosis (OR: 1.50 [95% CI: 1.14-1.99] P = .004) increased PICU mortality. Having "other" insurance type (OR: 1.58 [95% CI: 1.11-2.24] P = .010) or being Asian/Indian/Pacific Islander (OR: 1.35 [95% CI: 1.01-1.81] P = .042) seemed also to be mortality risk factors; however, because of heterogeneity and small group sizes (1.7% and 2.5% of the study population, respectively), these results are inconclusive. CONCLUSIONS: Although gender, age, and diagnosis showed an effect on severity of illness-adjusted PICU mortality, race/ethnicity did not. Additional investigation is warranted because the present results (ie, insurance type) may be proxy measurements for other influences not collected in this database, such as sociocultural and socioeconomic factors.

Recurrent delirium after surgery for congenital heart disease in an infant.

OBJECTIVE: The objective of this article is to describe a case of recurrent delirium after cardiac surgery in an infant. DESIGN: Case report. The institutional review board at Children's Hospital Los Angeles waived the need for informed consent. SETTING: Cardiothoracic intensive care unit in a freestanding children's hospital. PATIENT: A male infant with hypoplastic left heart syndrome who developed delirium on consecutive admissions to the cardiothoracic intensive care unit after cardiac surgery. INTERVENTION: Pharmacologic intervention using the atypical antipsychotic olanzapine. MEASUREMENTS AND MAIN RESULTS: The symptoms of delirium resolved with the initiation and continuation of olanzapine on both occasions. CONCLUSION: Delirium is a common, but often unrecognized, diagnosis in the intensive care unit. Its early recognition and treatment may prevent unnecessary use of narcotics and benzodiazepines, decrease length of stay and may improve long-term neurocognitive function. This case report describes an infant who developed discrete, consecutive episodes of delirium following surgery for congenital heart disease. Both episodes were treated effectively with olanzapine.

Children with corrected or palliated congenital heart disease on home mechanical ventilation.

Infants and children with surgically corrected or palliated congenital heart disease (CHD) are at risk for chronic respiratory failure, necessitating home mechanical ventilation (HMV) via tracheostomy. However, very little data exists on this population or their outcomes. We conducted a retrospective chart review of all children with CHD enrolled in the Childrens Hospital Los Angeles HMV program between 1994 and 2009. Data were collected on type of heart lesion, surgeries performed, number of failed extubations, timing of tracheostomy, mortality, length of time on HMV, weaning status, associated co-morbidities, and Risk Adjusted classification for Congenital Heart Surgery (RACHS-1) category. Thirty-five children were identified; six with single ventricle anatomy, who received palliative procedures. Twenty-three (66%) patients are alive; 8 (23%) living patients have been weaned off HMV. Twelve (34%) patients are deceased. The incidence of mortality for single ventricle patients was 50%, and only one of the surviving children has received final palliation and weaned off HMV. Eight of nine patients (89%) with a RACHS score > or =4 died, and none have been weaned off of HMV. The 5-year survival for all CHD HMV patients was 68%; 90% for patients with RACHS < or =3; and 12% for patients with score > or =4. Children with more complex lesions, as demonstrated by single ventricle physiology or greater RACHS scores, had higher mortality rates and less success weaning off HMV. This case series suggests that caregivers should give serious consideration to the type of heart defect as they advise families considering HMV in children with CHD.

Amiodarone versus procainamide for the acute treatment of recurrent supraventricular tachycardia in pediatric patients.

BACKGROUND: Intravenous amiodarone and procainamide are both used as therapies for refractory supraventricular tachycardia (SVT). However, no studies have compared the efficacy and safety of these agents in pediatric patients. METHODS AND RESULTS: All patients treated with intravenous amiodarone or procainamide during 25 consecutive months for the following mechanisms of SVT were included: orthodromic reciprocating tachycardia, intra-atrial reentrant tachycardia, and ectopic atrial tachycardia; junctional ectopic tachycardia was excluded. Treatment response was categorized as full success, partial success, or failure. Partial success was defined as clinical improvement and/or arrhythmia control but not meeting full success criteria. Adverse events were classified as major (requiring resuscitation) or minor (management changes). There were 40 episodes of SVT in 37 patients (median age, 34 days; 24 with congenital heart disease). Amiodarone was the initial therapy in 26 cases and procainamide in 14 cases. If partial and full success are combined, procainamide was successful in 71% of cases compared with 34% for amiodarone (P=0.046). If partial success is considered a treatment failure, procainamide was successful in 50% compared with 15% for amiodarone (P=0.029). Ten patients received the second medication after the first failed. Success was achieved in 5 of 8 amiodarone-to-procainamide crossovers compared with 1 of 2 procainamide-to-amiodarone crossovers. One major and 10 minor adverse events occurred in amiodarone patients versus 6 minor adverse events in procainamide patients (P=NS). CONCLUSIONS: In this cohort, procainamide achieved greater success compared with amiodarone in the management of recurrent SVT without statistically significant differences in adverse event frequency.

Reducing the incidence of necrotizing enterocolitis in neonates with hypoplastic left heart syndrome with the introduction of an enteral feed protocol.

OBJECTIVE: Neonates with hypoplastic left heart syndrome are prone to gastrointestinal complications, including necrotizing enterocolitis, during initiation or advancement of enteral feeds. A feeding protocol was developed to standardize practice across a multidisciplinary team. The purpose of this study was to examine the impact of a standardized feeding protocol on the incidence of necrotizing enterocolitis and overall postoperative gastrointestinal morbidity. DESIGN: Retrospective case-control study. SETTING: Cardiothoracic intensive care unit of a tertiary care children's hospital. PATIENTS: Ninety-eight neonates with hypoplastic left heart syndrome admitted to the cardiothoracic intensive care unit after first-stage palliation. INTERVENTION: A retrospective chart review was performed. Two groups were analyzed: the preprotocol group (n = 52) was examined from January 2000 through December 31, 2001, and the postprotocol group (n = 46) from February 2002 through December 31, 2003. MEASUREMENTS AND MAIN RESULTS: The incidence of suspected or diagnosed necrotizing enterocolitis as defined by the modified Bell staging criteria was recorded. Data were also collected regarding postoperative day of enteral feed initiation, postoperative day full feeds attained, and postoperative hospital length of stay. Necrotizing enterocolitis was detected in 14 preprotocol (27%) and three postprotocol (6.5%) patients (p < .01). Enteral feeds were initiated later in the postprotocol group (7.5 vs. 5.5 days, p < .001), and number of days to full feeds was also later in the postprotocol group (7 vs. 4 days, p = .02). Hospital length of stay tended to be shorter in the postprotocol group (21.5 vs. 28 days, p = .25). CONCLUSION: Measures directed at reducing the incidence of necrotizing enterocolitis may reduce morbidity in neonates with hypoplastic left heart syndrome and reduce cost by decreasing hospital length of stay. A standardized feeding protocol instituted to address these problems likely contributed to reducing the incidence of necrotizing enterocolitis in this high-risk population.

Hand hygiene adherence is influenced by the behavior of role models.

OBJECTIVE: Proper hand hygiene (HH) reduces nosocomial infections. Therefore, factors that influence HH behavior of healthcare workers are of great interest. We hypothesized that strict HH adherence by supervisor role models would improve the HH behavior of junior staff. DESIGN: Prospective observational study. SETTING: Pediatric and cardiac intensive care units of a tertiary care children's hospital. SUBJECTS: Two critical care fellows and four nurse orientees. INTERVENTIONS: First, we observed and recorded HH adherence of the fellows and nurse orientees and their respective supervising attending physician or nurse preceptor during daily patient care. Subsequently, we paired the same fellows and nurse orientees with a different supervisor who maintained strict HH adherence, and again noted HH adherence. We used measures of HH opportunities and HH adherence consistent with guidelines set by the Centers for Disease Control and Prevention and Association for Professionals in Infection Control and Epidemiology. MEASUREMENTS AND MAIN RESULTS: HH adherence by fellows and nurse orientees at baseline was 22% of 200 HH opportunities, and improved to 56% of 234 opportunities as a result of role modeling--an average increase of 34% points (95% confidence interval, 18.7-51; p < 0.01 by linear regression), representing a HH adherence rate greater than 1.5 times that of the baseline. The control senior practitioners' HH adherence rate was 20% of 180 opportunities compared with the study senior practitioners' HH adherence of 94% of 187 opportunities--an average difference of 72% points higher compared with the control senior practitioners (95% confidence interval, 56-88.3; p < 0.01 by linear regression). CONCLUSIONS: HH adherence of junior practitioners improved under the supervision of adherent role models. These results suggest that HH behavior of senior practitioners plays a crucial influence on other staff. Senior healthcare practitioners should consider the important role they may play in reinforcing or weakening a culture of patient safety and proper HH.

Mesenteric blood flow velocities in the newborn with single-ventricle physiology: modified Blalock-Taussig shunt versus right ventricle-pulmonary artery conduit.

BACKGROUND: Neonates with ductal-dependent single-ventricle congenital heart disease palliated with a modified Blalock-Taussig shunt (mBTS) commonly have retrograde diastolic flow in the aorta, which may place them at increased risk of mesenteric ischemia. Recently, palliation with a right ventricle-to-pulmonary artery conduit, known as the Sano procedure, has been shown to eliminate retrograde diastolic flow, theoretically leading to better systemic perfusion. OBJECTIVE: To compare the changes in superior mesenteric artery (SMA) and celiac artery velocities and flow after a bolus enteral feed in patients with single-ventricle congenital heart disease palliated with an mBTS vs. those palliated with the right ventricle-to-pulmonary artery conduit. DESIGN: Prospective clinical study. SETTING: Cardiothoracic intensive care unit and pediatric ward of a tertiary care children's hospital. PATIENTS: A total of 27 patients with single-ventricle congenital heart disease (15 with mBTS, 12 with Sano) after stage-1 palliation. INTERVENTION: Doppler ultrasound of the SMA and celiac artery was performed 30 mins before and after a bolus enteral feed. MEASUREMENTS AND MAIN RESULTS: SMA and celiac artery peak systolic flow velocity, mean flow velocity, and time-velocity integral were measured. After a bolus enteral feed, 8 of 15 infants palliated with an mBTS had retrograde diastolic flow through the SMA yet demonstrated significant increases in all variables of both the SMA and celiac artery flow velocities (SMA peak systolic flow velocity: 0.96 +/- 0.33 vs. 1.2 +/- 0.4 m/sec, p = .01). Those palliated with the Sano procedure did not demonstrate SMA retrograde diastolic flow but also did not have any significant changes in their mesenteric flow variables (SMA peak systolic flow velocity: 0.79 +/- 0.16 vs. 0.89 +/- 0.26 m/sec, p = .2). CONCLUSION: Postprandial retrograde diastolic flow was observed in the majority of patients palliated with an mBTS vs. none of the patients in the Sano group. However, contrary to expectations, postprandial mesenteric blood flow velocities in those palliated with an mBTS are significantly higher than in Sano patients, although the increase is not as high as that historically seen in normal neonates. This may place this population at risk for mesenteric ischemia and feeding intolerance in the postoperative period, and the risk may be even greater for those neonates palliated with a right ventricle-to-pulmonary artery conduit.

Gastrointestinal morbidity after Norwood palliation for hypoplastic left heart syndrome.

BACKGROUND: Neonates with hypoplastic left heart syndrome are at high risk for developing gastrointestinal complications after first stage palliation. These complications likely play a major role in their morbidity and mortality. The goal of this review was to examine the incidence and clinical impact of gastrointestinal morbidities in these newborns. METHODS: The charts of all neonates with hypoplastic left heart syndrome who underwent stage-one palliation between January 1997 and December 2001 were reviewed to determine the incidence of gastrointestinal complications. Demographic, perioperative, and procedural variables were collected and correlated with major gastrointestinal problems. RESULTS: There were 117 patients in our study population, and survival to discharge was 87% (102 of 117). Gastrointestinal complications occurred in 48 (41%), including 18% with necrotizing enterocolitis, 18% who required home feeding tubes, and 8% who required prolonged hospital length of stay for nutritional support. These infants had a longer length of stay (52 days versus 22 days; p < 0.0001). Multivariate logistic regression analysis revealed that weight less than 2.5 kg and development of necrotizing enterocolitis were each independently related to death. Neonates with a birth weight less than 2.5 kg had an odds ratio for death of 5.7 (95% confidence interval: 1.14 to 28.86), and the odds ratio for death with necrotizing enterocolitis was 5.6 (95% confidence interval: 1.55 to 20.67). CONCLUSIONS: Gastrointestinal complications in infants with hypoplastic left heart syndrome are common, and necrotizing enterocolitis increases the risk of death. Measures directed at reducing the incidence of gastrointestinal complications may improve outcomes and reduce costs in this population.