The Inadequate Oxygen Delivery Index and Low Cardiac Output Syndrome Score As Predictors of Adverse Events Associated With Low Cardiac Output Syndrome Early After Cardiac Bypass.

OBJECTIVES: To evaluate the effectiveness of two scoring systems, the inadequate oxygen delivery index, a risk analytics algorithm (Etiometry, Boston, MA) and the Low Cardiac Output Syndrome Score, in predicting adverse events recognized as indicative of low cardiac output syndrome within 72 hours of surgery. DESIGN: A retrospective observational pair-matched study. SETTING: Tertiary pediatric cardiac ICU. PATIENTS: Children undergoing cardiac bypass for congenital heart defects. Cases experienced an adverse event linked to low cardiac output syndrome in the 72 hours following surgery (extracorporeal membrane oxygenation, renal replacement therapy, cardiopulmonary resuscitation, and necrotizing enterocolitis) and were matched with a control patient on criteria of procedure, diagnosis, and age who experienced no such event. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of a total 536 bypass operations in the study period, 38 patients experienced one of the defined events. Twenty-eight cases were included in the study after removing patients who suffered an event after 72 hours or who had insufficient data. Clinical and laboratory data were collected to derive scores for the first 12 hours after surgery. The inadequate oxygen delivery index was calculated by Etiometry using vital signs and laboratory data. A modified Low Cardiac Output Syndrome Score was calculated from clinical and therapeutic markers. The mean inadequate oxygen delivery and modified Low Cardiac Output Syndrome Score were compared within each matched pair using the Wilcoxon signed-rank test. Inadequate oxygen delivery correctly differentiated adverse events in 13 of 28 matched pairs, with no evidence of inadequate oxygen delivery being higher in cases (p = 0.71). Modified Low Cardiac Output Syndrome Score correctly differentiated adverse events in 23 of 28 matched pairs, with strong evidence of a raised score in low cardiac output syndrome cases (p < 0.01). CONCLUSIONS: Although inadequate oxygen delivery is an Food and Drug Administration approved indicator of risk for low mixed venous oxygen saturation, early postoperative average values were not linked with medium-term adverse events. The indicators included in the modified Low Cardiac Output Syndrome Score had a much stronger association with the specified adverse events.

Global perspective on training and staffing for paediatric cardiac critical care.

This manuscript provides a global perspective on physician and nursing education and training in paediatric cardiac critical care, including available resources and delivery of care models with representatives from several regions of the world including Africa, Israel, Asia, Australasia, Europe, South America, and the United States of America.

Flecainide versus digoxin for fetal supraventricular tachycardia: Comparison of two drug treatment protocols.

BACKGROUND: The optimal treatment for fetal supraventricular tachycardia (SVT) with 1:1 atrioventricular relationship is unclear. OBJECTIVE: We compared the effectiveness of transplacental treatment protocols used in 2 centers. METHODS: Pharmacologic treatment was used in 84 fetuses. Maternal oral flecainide was the primary therapy in center 1 (n = 34) and intravenous maternal digoxin in center 2 (n = 50). SVT mechanism was classified by mechanical ventriculoatrial (VA) time intervals as short VA or long VA. Treatment success was defined as conversion to sinus rhythm (SR), or rate control, defined as >15% rate reduction. RESULTS: Short VA interval occurred in 67 fetuses (80%) and long VA in 17 (20%). Hydrops was present 28 of 84 (33%). For short VA SVT, conversion to SR was 29 of 42 (69%) for digoxin and 24 of 25 (96%) for flecainide (P = .01). For long VA SVT, conversion to SR and rate control was 4 of 8 (50%) and 0 of 8, respectively, for digoxin, and 6 of 9 (67%) and 2 of 9 (cumulative 89%) for flecainide (P = .13). In nonhydropic fetuses, digoxin was successful in 23 of 29 (79%) and flecainide in 26 of 27 (96%) (P = .10). In hydrops, digoxin was successful in 8 of 21 (38%), flecainide alone in 6 of 7 (86%, P = .07 vs digoxin), and flecainide ± amiodarone in 7 of 7 (100%) (P = .01). Intrauterine or neonatal death occurred in 9 of 21 hydropic fetuses treated with digoxin (43%), compared to 0 of 7 (P = .06) treated with flecainide. CONCLUSIONS: Flecainide was more effective than digoxin, especially when hydrops was present. No adverse fetal outcomes were attributed to flecainide.

Right ventricular dysfunction in children supported with pulsatile ventricular assist devices.

OBJECTIVES: To describe the incidence and severity of right ventricular dysfunction (RVD) in pediatric ventricular assist device (VAD) recipients and to identify the preoperative characteristics associated with RVD and their effect on outcomes. METHODS: Children bridged to transplantation from 2004 to 2011 were included. RVD was defined as the use of a left VAD (LVAD) with an elevated central venous pressure of >16 mm Hg with inotropic therapy and/or inhaled nitric oxide for >96 hours or biventricular assist (BiVAD). RESULTS: A total of 57 children (median age, 2.97 years; range 35 days to 15.8 years) were supported. Of the 57, 43 (75%) had an LVAD, and of those, 10 developed RVD. The remaining 14 (25%) required BiVAD. Thus, RVD occurred in 24 of 57 patients (42%). Preoperative variables such as younger age (P = .01), use of extracorporeal mechanical support (P = .006), and elevated urea (P = .03), creatinine (P = .02), and bilirubin (P = .001) were associated with RVD. Multiple logistic regression analysis indicated that elevated urea and extracorporeal mechanical support (odds ratio, 26.4; 95% confidence interval, 2.3-307.3; and odds ratio, 27.8; 95% confidence interval, 2.5-312.3, respectively) were risk factors for BiVAD. The patients who developed RVD on LVAD had a complicated postoperative course but excellent survival (100%), comparable to those with preserved right ventricular function (91%). The survival for those requiring BiVAD was reduced (71%). CONCLUSIONS: RVD occurred in approximately 40% of pediatric VAD recipients and affects their peri-implantation morbidity and bridging outcomes. Preoperative extracorporeal membrane oxygenation and elevated urea were risk factors for BiVAD. Additional studies of the management of RVD in children after VAD implantation are warranted.

Regionalization in neonatal congenital heart surgery: the impact of distance on outcome after discharge.

Studies have shown improved perioperative outcomes after neonatal heart surgery at centers with greater surgical volumes. The impact of increasing distance from such centers on outcome after discharge has not yet been reported. Chart review and cross-sectional survey were performed on children discharged or transferred after undergoing neonatal congenital heart surgery as neonates (<30 days of age) from January 2005 to June 2006. The association of distance from center with mortality and adverse events was analyzed by univariate and multivariate regression and stratified by the Risk Adjustment for Congenital Heart Surgery-1 for complexity. Among 217 patients, those living further from the surgical center were smaller and older at surgery and more likely to be RACHS-1 class 6. Overall mortality was 8% (16 of 202) and was not associated with distance. Surveys were completed by 109 (54%) families with mean follow-up of 24 (± 3) months. Unplanned admissions after discharge and unplanned interventions occurred in 45% and 40% of patients, respectively. After adjusting for case complexity, living 90-300 min away from the surgical center was associated with fewer unplanned admissions compared with those living <90 min away. After neonatal cardiac surgery, adverse events were common. Distance from the surgical center was not associated with mortality, but it was associated with morbidity in a nonlinear fashion. This relation, its mediators, and its possible impact on mortality and later outcomes warrant further study to aid in planning appropriate patient follow-up.

Early systemic-to-pulmonary artery shunt intervention in neonates with congenital heart disease.

OBJECTIVE: To determine the incidence, risk factors, and outcomes after early, unplanned intervention on systemic-to-pulmonary artery shunts in neonates. METHODS: We retrospectively studied all neonates undergoing systemic-to-pulmonary artery shunt placement at The Children's Hospital of Philadelphia between September 1, 2002, and May 1, 2005. Patients requiring transcatheter or surgical systemic-to-pulmonary artery shunt intervention before discharge were compared with those not undergoing shunt intervention. RESULTS: A total of 206 patients underwent shunt placement. Diagnoses included hypoplastic left heart syndrome (62.1%), pulmonary atresia (15%), tricuspid atresia (4.9%), tetralogy of Fallot (2.4%), and other lesions with obstruction to systemic (10.7%) or pulmonary blood flow (4.9%). Twenty-one interventions occurred in 20 patients (9.7%). Risk factors for intervention included heterotaxy syndrome (P = .04), congenital abnormality (P = .04), and a trend toward lower birthweight. In patients with a modified Blalock-Taussig shunt, similar risk factors were identified and the incidence of intervention decreased with increasing shunt size. In-hospital mortality was 30% (6/20) for the cases and 8.1% (15/186) for the nonintervention group (P = .02). Long-term survival was significantly lower in patients requiring intervention (P = .002). This group also had a higher incidence of infections (P < .001) and extracorporeal membrane oxygenation (P < .001), and longer hospital stay (P = .001). CONCLUSIONS: In neonates undergoing systemic-to-pulmonary artery shunt placement, approximately 10% underwent shunt intervention before discharge. Some factors, such as low birthweight, shunt size, noncardiac congenital abnormalities, and heterotaxy syndrome, may help identify patients at risk. Patients undergoing intervention experienced increased morbidity and mortality.

Risk factors for catheter-associated bloodstream infections in a Pediatric Cardiac Intensive Care Unit.

BACKGROUND: Catheter-associated bloodstream infections (CA-BSIs) are an important complication of care in children hospitalized with complex congenital heart disease; however, little is known about risk factors for CA-BSI in these patients. METHODS: We conducted a retrospective nested case-control study in the 26-bed Cardiac Intensive Care Unit (CICU) at the Children's Hospital of Philadelphia.We identified all primary CA-BSIs in the CICU between January 1, 2004 and June 30, 2005. Controls were selected from rosters of CICU patients that were admitted during the same time period. Incidence density sampling was used to match cases and controls on time at risk. Data on demographic features and clinical characteristics were abstracted from the medical record. In addition, detailed data on exposures to medical devices, interventions, and therapeutic agents were gathered during a 4-day period immediately before the onset of infection (cases) or study entry (controls). RESULTS: We identified 59 children who developed a CA-BSI. The median time from catheter insertion to onset of infection was 9 days. Over half of infections were caused by gram positive organisms. On multivariable analysis, only tunneled catheters emerged as an independent risk factor for infection. CONCLUSION: In this study population, tunneled catheters were associated with a higher risk of CA-BSI, possibly because of the catheter material. Additionally, we did not find that the burden of catheters and medical devices was associated with an increased risk of infection. Because most CA-BSIs in our study population occurred > or =7 days after catheter insertion, strict attention to aseptic technique when using or dressing a catheter might reduce CA-BSI rates in the pediatric CICU.

A contemporary comparison of the effect of shunt type in hypoplastic left heart syndrome on the hemodynamics and outcome at Fontan completion.

OBJECTIVE: We previously reported no difference in morbidity or mortality in a cohort of infants undergoing stage 1 and 2 reconstructions for hypoplastic left heart syndrome with either a modified Blalock-Taussig shunt or a right ventricular to pulmonary artery conduit. This article compares the hemodynamics and perioperative course at the time of the Fontan completion and reports longer-term survival for this cohort. METHODS: We retrospectively reviewed the hospital records of all patients who underwent stage 1 reconstruction between January 2002 and May 2005 and subsequent surgical procedures, as well as cross-sectional analysis of hospital survivors. RESULTS: A total of 176 patients with hypoplastic left heart syndrome or a variant underwent stage 1 reconstruction with either modified Blalock-Taussig shunt (n = 114) or right ventricular to pulmonary artery conduit (n = 62). Shunt selection was at the discretion of the surgeon. The median duration of follow-up was 58 months (range 1-87 months). By Kaplan-Meier analysis, shunt type did not influence survival or freedom from transplant at 5 years (right ventricular to pulmonary artery conduit 61%; 95% confidence limit, 47-72 vs modified Blalock-Taussig shunt 70%; 95% confidence limit, 60-77; P = .55). A total of 107 patients underwent Fontan (69 modified Blalock-Taussig shunts and 38 right ventricular to pulmonary artery conduits) with 98% (105/107) early survival. Patients with a right ventricular to pulmonary artery conduit shunt pre-Fontan had higher pulmonary artery (13 +/- 8 mm Hg vs 11 +/- 3 mm Hg, P = .026) and common atrial (8 +/- 2.3 mm Hg vs 6.8 +/- 2.7 mm Hg, P = .039) pressures. By echocardiography evaluation, there was more qualitative moderate to severe ventricular dysfunction (right ventricular to pulmonary artery conduit 31% [12/36] vs modified Blalock-Taussig shunt 17% [11/67], P = .05) and moderate to severe atrioventricular valve regurgitation (right ventricular to pulmonary artery conduit 40% [14/35] vs modified Blalock-Taussig shunt 16% [11/67], P = .01) in the right ventricular to pulmonary artery conduit group. Use of diuretic therapy, angiotensin-converting enzyme inhibition, reflux medications, and tube feedings were not different between groups. Overall, 5 patients underwent heart transplantation (right ventricular to pulmonary artery conduit 4 vs modified Blalock-Taussig shunt 1, P = .1) before Fontan. There was no difference in age or weight at Fontan, bypass time, intensive care unit or hospital length of stay, postoperative pleural effusions, or need for reoperation between groups. CONCLUSIONS: Interim analyses continue to suggest there is no survival advantage of one shunt type compared with the other. Longer-term follow-up of a randomized patient population remains of utmost importance.

Reintervention for arch obstruction after stage 1 reconstruction does not adversely affect survival or outcome at Fontan completion.

OBJECTIVE: To determine the effect of reintervention for coarctation after stage 1 reconstruction for hypoplastic left heart syndrome and variants on survival, suitability for Fontan, and morbidity at Fontan. METHODS: A retrospective review of echocardiograms, catheterizations, hospital records of patients who underwent stage 1 reconstruction from January 2002 to May 2005, with a cross-sectional analysis of hospital survivors, was performed. Kaplan-Meier curves were derived for patients alive more than 30 days after stage 1 reconstruction. RESULTS: A total of 176 patients underwent stage 1 reconstruction. Forty-three patients (23%) underwent balloon angioplasty (n = 43) or surgical intervention (n = 4) for re-coarctation. Median time to intervention was 123 (1-316) days. Seven of 43 patients (16%) underwent more than 1 balloon angioplasty. Thirty-nine patients underwent intervention before stage 2 reconstruction, and 4 patients had intervention between stage 2 reconstruction and Fontan. Kaplan-Meier curves showed no difference in freedom from death or transplant between patients who did and did not undergo intervention for re-coarctation. Fontan completion was performed in 107 patients. By echocardiogram, the prevalence of moderate to severe ventricular dysfunction between groups was similar at Fontan; however, significant atrioventricular valve regurgitation was more common in patients who required intervention (28/33 vs 40/65, P = .02). Overall Fontan mortality was 2% and not different between groups. Length of stay was not different between patients with and without re-coarctation. CONCLUSIONS: Reintervention for coarctation after stage 1 reconstruction is common. Hemodynamic differences between groups did not affect Fontan completion, mortality, or hospital length of stay. Follow-up is necessary to determine the impact of re-coarctation on longer-term mortality and morbidity.

Morbidity and mortality after surgery for congenital cardiac disease in the infant born with low weight.

OBJECTIVE: Low weight at birth is a risk factor for increased mortality in infants undergoing surgery for congenitally malformed hearts. There has been a trend towards performing surgery in patients early, and for amenable lesions, in a single stage rather than following initial palliative procedures. Our goal was to report on the current incidences of morbidities and mortality in infants born with low weight and undergoing surgery for congenital cardiac disease. METHODS: We made a retrospective review of the data from patients meeting our criterions for entry from July, 2000, through July, 2004. The criterions for inclusion were weight at birth less than or equal to 2500 grams, and congenital cardiac malformations requiring surgery during the initial hospitalization. A criterion for exclusion was isolated persistent patency of the arterial duct. We assessed preoperative, intraoperative, and postoperative variables. RESULTS: We found a total of 105 patients meeting the criterions for inclusion. The median weight at birth was 2130 grams, and median gestational age was 36 weeks. The most common morbidity identified was infections of the blood stream. Infections, and chronic lung disease, were associated with increased length of stay. Survival overall was 76%. Patients with hypoplastic left heart syndrome, or a variant thereof, had the lowest survival, of 62%. The needs for cardiopulmonary resuscitation, or extracorporeal membrane oxygenation, post-operatively were the only factors identified as independent risk factors for mortality. CONCLUSION: Patients undergoing surgery during infancy for congenital cardiac disease who are born with low weight have a higher mortality and morbidity than those born with normal weight.