Janet M. Simsic

Nesiritide in infants and children with congestive heart failure.

Objectives: Nesiritide (synthetic B-type natriuretic peptide) has been shown to be effective in the management of acute decompensated heart failure in adults. The role of nesiritide in pediatric heart failure has not been examined. In the present study, we reviewed our initial experience with nesiritide in children with primary heart failure or low cardiac output after heart surgery. Methods: Nesiritide was administered in an open-label fashion to patients with heart failure who were already receiving inotropic and diuretic therapy. Between July 2003 and August 2004, 30 patients aged 5 days to 16.7 yrs (median age, 4.6 months) received nesiritide therapy. Diagnoses included single-ventricle congenital defect (n = 5), two-ventricle congenital defect (n = 13), heart transplant (n = 5), and dilated cardiomyopathy (n = 7). Sixteen patients were started on nesiritide within 2 wks of corrective or palliative heart surgery. The majority of subjects (n = 24) received an initial bolus dose. Continuous infusion dosage ranged between 0.005 and 0.02 &mgr;g·kg−1·min−1. Nesiritide was discontinued for possible side effects in two patients (arrhythmia and hypotension). Duration of therapy ranged from 1 to 24 days (median, 4 days). Results: Administration of nesiritide was associated with improvement in fluid balance from positive 0.8 ± 1.9 mL·kg−1·hr−1 at baseline to negative 0.3 ± 1.8 mL·kg−1·hr−1 after 24 hrs of therapy (p = .02). There was a nonsignificant trend toward a reduction in right atrial pressure (9.2 ± 3.9 vs. 11.2 ± 4.1, p = .08). Conclusions: Nesiritide is well tolerated in children with heart failure and is associated with improved diuresis. Further prospective studies will be needed to compare nesiritide with other vasoactive agents and examine the cost-efficacy of this therapy.

Recombinant Factor VIIa to Control Excessive Bleeding Following Surgery for Congenital Heart Disease in Pediatric Patients

The purpose of this article is to evaluate the efficacy of recombinant factor VII (rFVIIa) in the treatment of bleeding following cardiac surgery in a pediatric population. The study included a case series of postcardiac surgical patients with chest tube output of= 4 mL/kg/h for the initial 3 postoperative hours who received rFVIIa. Chest tube output for the 3 hours before and the 3 hours after rFVIIa was compared using a pairedt test. In addition, chest tube output for the initial 3 postoperative hours and the 3 hours following rFVIIa was compared to 8 control patients who did not require rFVIIa. Recombinant factor VIIa was administered to 9 children (age = 9 ± 4 years) following repair of tetralogy of Fallot (6), closure of ventricular septal defect (1), closure of sinus venosus atrial septal defect (1), and mitral valve repair (1). Chest tube output for the initial 3 postoperative hours prior to the administration of rFVIIa was 5.8 ± 2.8 mL/kg/h and decreased to 2.0 ± 1.3 mL/kg/h for the 3 hours following the administration of rFVIIa (P= .002). In the patients that did not receive rFVIIa, chest tube output for the first 3 postoperative hours was 1.6 ± 0.9 mL/kg/h and 1.2 ± 0.6 mL/kg/h for the next 3 hours (P= nonsignificant when compared to chest tube output for the 3 hours following rFVIIa in patients who received rFVIIa). No adverse effects were noted. Recombinant factor VIIa decreased chest tubing bleeding following cardiac surgery in children. Given its potential therapeutic impact, rFVIIa warrants further investigation in the pediatric cardiac population.

Postoperative Cerebral Oxygenation in Hypoplastic Left Heart Syndrome After the Norwood Procedure

BACKGROUND Cerebral near-infrared spectroscopy (NIRS) is being used with increasing frequency in the care of pediatric patients after surgery for congenital heart disease. Near-infrared spectroscopy provides a means of evaluating regional cerebral oxygen saturation (cSaO(2)) noninvasively, with correlations to cardiac output and central venous saturation. Prior studies have demonstrated that systemic venous saturation can predict outcome after the Norwood procedure. With this in mind, we sought to determine whether regional cSaO(2) by NIRS technology could predict risk of adverse outcome after the Norwood procedure. METHODS We reviewed the first 48 hours of postoperative hemodynamic data on 50 patients with hypoplastic left heart syndrome at our institution who underwent the Norwood procedure. Cerebral oxygen saturation data within 48 hours of surgery were analyzed for association with subsequent adverse outcome, which was defined as intensive care unit length of stay greater than 30 days, need for extracorporeal membrane oxygenation, or hospital death after 48 hours. RESULTS There were 18 adverse events among the 50 subjects. The mean cSaO(2) for the entire cohort at 1 hour, 4 hours, and 48 hours after surgery was 51% +/- 7.5%, 50% +/- 9.4%, and 59% +/- 8.1%, respectively. Mean cSaO(2) for the first 48 postoperative hours of less than 56% was a risk factor for subsequent adverse outcome (odds ratio 11.9, 95% confidence interval: 2.5 to 55.8). Mean cerebral NIRs of less than 56% over the first 48 hours after surgery yielded a sensitivity of 75.0% and a specificity of 79.4% to predict those at risk for subsequent adverse events. CONCLUSIONS Low regional cerebral oxygen saturation by NIRS in the first 48 hours after the Norwood procedure has a strong association with subsequent adverse outcome. Monitoring of cerebral saturation can serve as a valuable monitoring tool and can identify patients at risk for poor outcome.

The bidirectional Glenn operation: a risk factor analysis for morbidity and mortality.

OBJECTIVE Patients with single ventricle heart defects often undergo a palliative bidirectional Glenn operation. For this operation, we analyzed potential risk factors for morbidity and mortality. We also evaluated the effects of a persistent left superior vena cava by comparing the outcomes of unilateral and bilateral operations. METHODS We reviewed the clinical records of 270 consecutive patients who underwent a bidirectional Glenn operation between 2001 and 2007. A total of 226 patients underwent unilateral operations and 44 patients underwent bilateral operations. Patient characteristics included weight and age, single ventricle morphology, vena caval anatomy, and previous surgery. Operative details included cardiopulmonary bypass technique and duration, pulmonary artery management, hemi-Fontan construction, concomitant procedures, and hemodynamics. Outcome data included duration of chest tube drainage, lengths of intensive care unit and hospital stay, morbidity, and mortality (<30 days). RESULTS The median length of chest tube drainage was 2.4 days (range 1-20 days). Risk factors for prolonged drainage were elevated central venous pressure (P = .015) and transpulmonary gradient (P = .011). The median lengths of stay in the intensive care unit and hospital were 50 hours (range 20-1628 hours) and 5 days (range 2-83 days), respectively. Risk factors for both included prolonged cardiopulmonary bypass time, elevated central venous pressure and transpulmonary gradient, and right ventricular morphology. Overall, 72 of 270 patients (27%) had 116 postoperative complications. Risk factors included prolonged cardiopulmonary bypass time (P = .002) and elevated central venous pressure (P = .029). Mortality was 2 of 270 patients (0.7%). No risk factors for death were identified. Weight (median 6.8 kg vs 6.2 kg, P = .038) and age (median 186 days vs 159 days, P = .001) at the time of surgery were significantly greater in the bilateral bidirectional Glenn group compared with the unilateral group. However, there was no difference in any of the outcome variables. CONCLUSION Outcomes were adversely affected primarily by prolonged cardiopulmonary bypass time, elevated central venous pressure and transpulmonary gradient, and right ventricular morphology. Specifically, outcomes were unaffected by the presence of a left superior vena cava, cannulation strategy, or antegrade pulmonary blood flow. There were few differences between the unilateral and bilateral groups, none of which were postoperative outcomes.

One Thousand Repeat Sternotomies for Congenital Cardiac Surgery: Risk Factors for Reentry Injury

BACKGROUND Reentry injury is a risk associated with repeat sternotomy for cardiac surgery. This risk has been well defined for adults, but there is less information available for patients with congenital heart disease. The goal of this review was to identify the incidence, risk factors, and outcomes for reentry injury in patients with congenital heart disease. METHODS Eight hundred two patients with congenital heart disease had 1,000 consecutive repeat sternotomies between August 2000 and November 2007. Records were reviewed for demographics, history, operative techniques, and outcomes. Univariate risk factors for reentry injury and operative mortality were assessed. RESULTS Median age and weight were 2.1 years (range, 0.1 to 34.6 years) and 11 kg (range, 2.5 to 123 kg). There were 639 second, 287 third, and 74 fourth or higher sternotomies. There were 13 reentry injuries (1.3%) involving right ventricle-pulmonary artery conduits (n = 4), aorta or aortic conduits (n = 3), right ventricular outflow tract patches or pseudoaneurysms (n = 3), and others (n = 3). Risk factors for injury were presence of a right ventricle-pulmonary artery conduit (6 of 115 with conduit [5.2%] versus 7 of 885 without [0.8%]; p < 0.001) and sternotomy number (relative risk, 2.28; p < 0.001). Reentry injury was associated with longer procedure times (median, 420 minutes with injury versus 248 without; p < 0.001). Operative mortality occurred in 18 patients and was associated with sternotomy number and procedure time (p < 0.001), but not reentry injury (p = 0.2). CONCLUSIONS Risk of reentry injury during repeat sternotomy for congenital heart disease is low. Increasing sternotomy number and the presence of a right ventricle-pulmonary artery conduit are risk factors for reentry injury. However, reentry injury is not associated with increased risk of operative mortality.

Feeding Difficulty in Newborns Following Congenital Heart Surgery

OBJECTIVE Following neonatal congenital heart surgery, one of the factors impacting patient recovery is feeding difficulty. The aim of this study is to identify the risk factors. METHODS Patients who underwent surgery for congenital heart defects within the first 15 days of life were reviewed. Endpoints for feeding difficulty included: (1) a prolonged time to reach goal feeds; (2) a prolonged transition to oral feeds requiring tube feeds at discharge; and (3) additional procedures to facilitate feeding. Preoperative, operative, and postoperative data were examined to identify risk factors for feeding difficulty. RESULTS A total of 83 records were reviewed and showed the following feeding difficulties: 9 patients (10.8%) had a prolonged time to reach goal feeds, 37 (44.6%) had a prolonged time to transition to oral feeds, and 8 (9.6%) required subsequent procedures to facilitate feeding. Significant risk factors for all endpoints included an increased risk adjusted congenital heart surgery (RACHS) score and prolonged intubation. Significant risk factors for individual endpoints included return to the intensive care unit with an open chest for endpoint 1, and a single functional ventricle and the presence of a shunt for endpoint 3. The remaining factors (gestational age, weight at the time of surgery, being intubated at the time of surgery, underlying disease, utilization and time of cardiopulmonary bypass, utilization of trans-esophageal echocardiography, and surgical proximity to the aortic arch) had no significant effect on postoperative feeding. CONCLUSIONS Feeding difficulties are not uncommon following surgery for the correction of congenital heart defects, especially in the neonate. The most important risk factors appear to be an increased RACHS score and prolonged postoperative intubation. Hopefully, by defining the risk factors, proactive management strategies can be developed to minimize these problems following neonatal congenital heart surgery.

Do neonates with genetic abnormalities have an increased morbidity and mortality following cardiac surgery

INTRODUCTION Genetic abnormalities occur in approximately 20% of children with congenital heart disease. The purpose of this study was to evaluate the effect of genetic abnormalities on short-term outcomes following neonatal cardiac surgery. METHODS Retrospective review of all neonates (n = 609) undergoing cardiac surgery from January 2003 to December 2006. Genetic abnormalities were identified in 93 neonates (15%). Genetic abnormalities identified were 22q11.2 deletion (23), chromosomal abnormalities including various monosomies, trisomies, deletions, duplications, and inversions (17), dysmorphic undefined syndrome without recognized chromosomal abnormality (27), Down syndrome (9), laterality sequences (9), recognixed syndromes and genetic etiology including Mendelian (i.e. Alagille, CHARGE) (8). RESULTS Neonates with genetic abnormalities had lower birth weights and were older at time of surgery. There was no difference in operative variables, duration of mechanical ventilation or ICU length of stay between the two groups. There was an increase in total hospital length of stay and postoperative complications in the neonates with genetic abnormalities. Importantly, in hospital mortality was not different. CONCLUSION Neonates with genetic abnormalities have a higher risk of postoperative complications and a longer hospital length of stay. However, there is no increase in hospital mortality. This information may aid in patient management decisions and parental counseling. Longer-term studies are needed for understanding the total impact of genetic abnormalities on neonates with congenital heart disease.

Perioperative Effects and Safety of Nesiritide Following Cardiac Surgery in Children

Nesiritide (Natrecor, Scios Inc), human B-type natriuretic peptide, has hemodynamic effects that may be beneficial in pediatric patients after cardiac surgery. Experience with nesiritide and pediatrics is limited. The purpose of this study was to evaluate perioperative effects and safety of nesiritide in pediatric cardiothoracic surgery. Seventeen patients with congenital heart disease undergoing cardiac surgery were given a loading dose (1 µg/kg) while on cardiopulmonary bypass (constant flow) followed by continuous infusion for 24 hours (0.01 µg/kg/min × 6 hours, then 0.02 µg/kg/min × 18 hours). A 7% decrease in mean blood pressure was seen following nesiritide loading dose on cardiopulmonary bypass. No patient required intervention for hypotension while receiving nesiritide load or infusion. Nesiritide load during surgery and continuous infusion after cardiac surgery in pediatric patients resulted in no significant hemodynamic compromise.

Bloodstream Infections Increased After Delayed Sternal Closure: Cause or Coincidence

BACKGROUND Infants who undergo major cardiac operations are at risk for developing bloodstream infections which contribute to the morbidity, mortality, and cost of treatment. Determining what factors are associated with this increased risk of infection may aid in prevention. We sought to evaluate the practice of delayed sternal closure after neonatal cardiac surgery to determine its role as a risk factor for postoperative bloodstream infection. METHODS We reviewed 110 consecutive patients with hypoplastic left heart syndrome after stage 1 Norwood procedure at Childrens Healthcare of Atlanta. The rates of bloodstream infections were determined and risks analyzed with regard to postoperative status of sternal closure; primary versus delayed. RESULTS Delayed sternal closure was utilized in 67 of 110 patients (61%), while 43 patients had primary sternal closure in the operating room. Overall rate of bloodstream infection was 22% (24 of 110), with 83% (20 of 24) of infections occurring in the delayed closure group. Among infants with delayed closure, 30% developed bloodstream infection, as compared with 9% of patients with primary closure (p = 0.017). Patients with delayed closure had a fourfold increased risk (odds ratio 3.9, p = 0.03) of developing bloodstream infection in-hospital. Predominant organisms were coagulase negative Staphylococcus species; there was one case of mediastinitis. CONCLUSIONS Delayed sternal closure is associated with an increased likelihood of bloodstream infection and should be recognized as a risk factor after neonatal cardiac operations.

Association of feeding modality with interstage mortality after single-ventricle palliation.

OBJECTIVE Interstage mortality has been reported in 10% to 25% of hospital survivors after single-ventricle palliation. The purpose of this study was to examine the impact of feeding modality at discharge after single-ventricle palliation on interstage mortality. METHODS We conducted a retrospective review of all neonates undergoing single-ventricle palliation from January 2003 to January 2010. A total of 334 patients (90%) survived to hospital discharge, comprising the study group. Preoperative, operative, and postoperative variables were examined, including feeding method at discharge. Multivariate Poisson regression models were constructed to estimate the relative risk of interstage mortality. RESULTS Of 334 patients, 56 (17%) underwent gastrostomy tube ± Nissen. There was a statistically significant increase in interstage mortality for patients who underwent gastrostomy tube ± Nissen compared with patients who did not (relative risk, 2.38; 95% confidence interval, 1.05-5.40; P = .04]). Of the 278 patients who were not fed via a gastrostomy tube ± Nissen, 190 (68%) were fed with nasogastric feedings and 88 (32%) were fed entirely by mouth. There was no difference in interstage mortality between these 2 groups (relative risk, 0.92; 95% confidence interval, 0.31-2.73; P = .89). CONCLUSIONS Neonates undergoing single-ventricle palliation who require gastrostomy tube ± Nissen are at an increased risk of interstage mortality. The need for gastrostomy tube ± Nissen in this population may be a marker for other unmeasured comorbidities that place them at an increased risk of interstage mortality. Discharge with nasogastric feeds does not increase the risk of interstage mortality.