Variation and comparative effectiveness of patent ductus arteriosus pharmacotherapy in extremely low birth weight infants.

BACKGROUND: Patent ductus arteriosus (PDA) occurs in 70% of extremely low birth weight (ELBW, birth weight <1000 g) infants. Approximately 34% of ELBW infants with a PDA have spontaneous closure. Failure of the ductus arteriosus to close has been associated with multiple morbidities. OBJECTIVE: To examine variability over time and across hospitals in early therapeutic (2-7 day) use of indomethacin (INDO) vs ibuprofen (IBU) for PDA treatment in outborn ELBW infants and examine the outcomes and side effects of both pharmacological agents in this population. METHODS: Data were extracted from the Pediatric Health Information System. ELBW infants born between January 1, 2007 and December 31, 2010 and admitted on day of life 0 were eligible for inclusion. 732 infants had a PDA diagnosis and met inclusion criteria. We explored the variability in PDA pharmacotherapy over time and across hospitals. We compared outcomes of both agents for in-hospital mortality, need for surgical ligation, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, periventricular leukomalacia, renal failure, and persistent pulmonary hypertension. Statistical methods included chi square and multivariable regression analysis. Instrumental variable analysis was used to control for selection bias and omitted variables. RESULTS: There was large variability in PDA pharmacotherapy over time and across hospitals. INDO use declined as IBU use grew from 12.8 to 38.9%. There was no difference in hospital or NICU characteristics between high and low IBU using NICUs. Renal failure was more common in infants receiving INDO compared to IBU. CONCLUSION: We noted large variability in PDA pharmacotherapy. Renal failure was more common with INDO use. Until further studies to compare the long-term effects of both drugs, our data support IBU as the preferred medication for PDA pharmacotherapy in ELBW infants.

Extracorporeal membrane oxygenation support for intractable primary arrhythmias and complete congenital heart block in newborns and infants: short-term and medium-term outcomes.

OBJECTIVES: To describe the experience with extracorporeal membrane oxygenation support for intractable primary arrhythmias in newborns and infants. DESIGN: Retrospective study. SETTING: A tertiary care pediatric hospital. PATIENTS: Patients younger than 1 yr supported with extracorporeal membrane oxygenation for primary cardiac arrhythmias were identified from the institutional extracorporeal membrane oxygenation registry. INTERVENTIONS: Extracorporeal membrane oxygenation support. MEASUREMENTS AND MAIN RESULTS: Clinical characteristics and outcomes were investigated for patients with primary cardiac arrhythmia supported with extracorporeal membrane oxygenation. Outcomes investigated were time from initiation of extracorporeal membrane oxygenation support to arrhythmia control, duration of extracorporeal membrane oxygenation support, and results of interventions performed while supported with extracorporeal membrane oxygenation. We summarized the independent categorical and continuous variables using frequencies, percentages, and medians and ranges, respectively. Extracorporeal membrane oxygenation support was used in nine patients for rescue therapy for primary tachyarrhythmia and bradycardia. The primary arrhythmias were: focal atrial tachycardia (n = 2); reentrant supraventricular tachycardia (n = 3); junctional ectopic tachycardia (n = 2); and congenital complete atrioventricular block (n = 2) patients. Seven patients presented with severe hemodynamic compromise, with six patients requiring extracorporeal cardiopulmonary resuscitation. All patients required extracorporeal membrane oxygenation within 24 hrs of initial presentation. Balloon atrial septostomy was performed in three patients and ablation was performed in two patients. Sinus rhythm was achieved in all reentrant supraventricular tachycardia and rate control was established in both patients with focal atrial tachycardia and in one patient with junctional ectopic tachycardia while using extracorporeal membrane oxygenation support. All patients survived to hospital discharge, and median follow-up for the cohort was 5 yrs. There was one late death; all survivors had good overall and neurologic outcomes. CONCLUSIONS: The requirement of extracorporeal membrane oxygenation support in newborns and infants with intractable arrhythmia is rare. Extracorporeal membrane oxygenation support does potentially carry morbidity; however, to prevent arrhythmia-related mortality, extracorporeal membrane oxygenation support and/or extracorporeal cardiopulmonary resuscitation should be considered in the management of hemodynamically unstable primary arrhythmias as an emergent lifesaving procedure.

Implantation of a Berlin Heart ventricular assist device.

Until recently the only mode of mechanical circulatory support available in North America for use as bridge to cardiac transplantation in small children was extra-corporeal membrane oxygenation. However, since 2005 the Berlin Heart pediatric ventricular assist device has been increasingly widely used for both biventricular and left ventricular support. The device is available in a wide range of sizes, allowing its use in children as small as 5 kg and as large as 60 kg. It has been applied in end-stage heart failure of both structural/congenital and myopathic etiology (including myocarditis). In the article the technique for implantation of the device will be described, with focus on certain details that facilitate safe implantation and subsequent explantation, whether in the setting of a heart transplant operation or in the setting of recovery of native heart function.

The virtual crossmatch--a screening tool for sensitized pediatric heart transplant recipients.

Heart transplantation in the setting of human leukocyte antigen (HLA) sensitization is challenging, as a time-consuming prospective crossmatch (XM) may be required, severely limiting the number of potential donors. We evaluated a 'virtual XM', defining a positive virtual XM as the presence of recipient pre-formed anti-HLA antibodies to the prospective donor HLA type, and compared the virtual XM to a standard direct XM. Bead-based flow cytometric analysis was used to identify anti-HLA antibody (Ab) present in a child listed for heart transplantation. Using recipient serum, direct-flow cytometric T- and B-cell XM were run for potential donors against whose HLA type the recipient had specific antibodies (group 1, n = 7) and for potential donors with predicted compatible HLA types by virtual XM (group 2, n = 7). Results were expressed as median channel difference (MCD) between the control and recipient serum. A positive T-cell XM was defined as MCD > 50, whereas MCD > 100 constituted a positive B-cell result. The rate of T-cell reactivity was significantly less in group 2 than in group 1 (29% vs. 100%, p = 0.02); similarly, B-cell reactivity was also less for group 2 (14% vs. 100%, p = 0.005). The virtual XM was 100% sensitive in detecting positive flow cytometric XM results for T and B cells. Although only 72% specific in predicting a negative T-cell XM, and 86% specific for negative B-cell XM, the false negatives were weakly positive and would probably have been clinically acceptable. Currently, potentially suitable donor organs are often declined for lack of a prospective XM; these organs may ultimately be allocated to more distant recipients or perhaps not used at all. While further studies are needed, virtual XM has the potential to improve availability of organs for sensitized patients and improve the overall allocation process.

Home surveillance program prevents interstage mortality after the Norwood procedure.

OBJECTIVE: To determine whether early identification of physiologic variances associated with interstage death would reduce mortality, we developed a home surveillance program. METHODS: Patients discharged before initiation of home surveillance (group A, n = 63) were compared with patients discharged with an infant scale and pulse oximeter (group B, n = 24). Parents maintained a daily log of weight and arterial oxygen saturation according to pulse oximetry and were instructed to contact their physician in case of an arterial oxygen saturation less than 70% according to pulse oximetry, an acute weight loss of more than 30 g in 24 hours, or failure to gain at least 20 g during a 3-day period. RESULTS: Interstage mortality among infants surviving to discharge was 15.8% (n = 9/57) in group A and 0% (n = 0/24) in group B (P =.039). Surveillance criteria were breached for 13 of 24 group B patients: 12 patients with decreased arterial oxygen saturation according to pulse oximetry with or without poor weight gain and 1 patient with poor weight gain alone. These 13 patients underwent bidirectional superior cavopulmonary connection (stage 2 palliation) at an earlier age, 3.7 +/- 1.1 months of age versus 5.2 +/- 2.0 months for patients with an uncomplicated interstage course (P =.028). A growth curve was generated and showed reduced growth velocity between 4 and 5 months of age, with a plateau in growth beyond 5 months of age. CONCLUSION: Daily home surveillance of arterial oxygen saturation according to pulse oximetry and weight selected patients at increased risk of interstage death, permitting timely intervention, primarily with early stage 2 palliation, and was associated with improved interstage survival. Diminished growth identified 4 to 5 months after the Norwood procedure brings into question the value of delaying stage 2 palliation beyond 5 months of age.

Atrially based pericardial tunnel for central pulmonary artery construction.

Discontinuity of central intrapericardial pulmonary arteries requires reconstruction of a pulmonary artery confluence before cavopulmonary connection, whether this connection be by bidirectional Glenn or Fontan procedure. Reconstruction of the central pulmonary arteries has previously been described using material of poor or no growth potential. A method is described for central pulmonary artery reconstruction that provides growth potential and is based on previous experience with Fontan lateral tunnel construction.

Rapid safe central venous access in children and adults undergoing open cardiac operations.

A technique is described for percutaneous placement of central venous catheters under direct vision in children and adults undergoing open heart operations. The method is reliable, rapid, and safe, and avoids blind attempts at obtaining vascular access.

Repair of long-segment tracheal stenosis in infancy.

Long-segment stenosis of the trachea in infancy is a considerable surgical challenge because the infants are generally extremely ill and the airway is small. The optimal type of repair is not clearly defined. This report summarizes our experience with rib cartilage tracheoplasty done with cardiopulmonary bypass. Six patients underwent repair of long-segment tracheal stenosis between September 1987 and September 1994. The mean age was 14 weeks (range 1 to 58 weeks). Patients had stenosis of at least 70% of the tracheal length, typically with complete cartilaginous rings. In all patients stenosis was repaired by placement of a section of rib cartilage as an augmentation patch into the anterior surface of the trachea, which had been incised through the entire length of the stenosis. To avoid distal airway intubation, we used cardiopulmonary bypass for all procedures, with a mean bypass duration of 110 minutes (range 54 to 175 minutes). Mechanical ventilation was required for a median of 11 days after the operation (range 7 to 81 days), and the median postoperative hospital stay was 17 days (range 12 to 180 days). All patients are long-term survivors. Complications included the need for extracorporeal membrane oxygenation to treat ventricular dysfunction in one patient and graft dehiscence requiring revision of the distal graft in another. The latter patient has required several treatments with a bronchoscope for removal of granulation tissue. All other patients are free of symptoms and have normal growth with a mean follow-up of 4.7 years (range 5 months to 7.6 years). We conclude that rib cartilage tracheoplasty for long-segment tracheal stenosis provides excellent results in short and intermediate follow-up. In addition, the use of cardiopulmonary bypass allows an unobstructed view of the tiny infant airway and thus permits a precise repair.

Modification of the maze procedure for atrial flutter and atrial fibrillation. I. Rationale and surgical results.

The original maze procedure that was described for the treatment of patients with atrial fibrillation was followed by an unacceptable incidence of two problems: (1) the frequent inability to generate an appropriate sinus tachycardia in response to maximal exercise and (2) occasional left atrial dysfunction. In an effort to overcome these problems, we modified the original technique (maze I) twice. The results of these modifications culminated in the maze III procedure, which is associated with a higher incidence of postoperative sinus rhythm, improved long-term sinus node function, fewer pacemaker requirements, less arrhythmia recurrence, and improved long-term atrial transport function. In addition, the maze III procedure is technically less demanding than either the maze I or maze II procedure. Therefore, the maze III procedure is now the technique of choice for the management of medically refractory atrial fibrillation.

Modification of the maze procedure for atrial flutter and atrial fibrillation. II. Surgical technique of the maze III procedure.

The operative technique of the maze III procedure for the treatment of patients with medically refractory atrial flutter and atrial fibrillation is described in a sequential fashion. The accompanying diagrams of the procedure are illustrated from the view of the operating surgeon.

Use of aprotinin in pediatric lung transplantation.

BACKGROUND: Aprotinin has been shown to decrease perioperative bleeding in adults undergoing cardiac surgery. We evaluated its efficacy in reducing blood loss in pediatric lung transplantation. METHODS: Aprotinin was given to a group of pediatric lung transplant recipients (n = 24) identified as being at high risk for bleeding by virtue of preoperative diagnosis of cystic fibrosis or previous cardiothoracic operation (group 1). Comparison was made to a group of pediatric recipients (n = 19) believed to be at low risk for bleeding who did not receive aprotinin (group 2). All transplantations were accomplished with the use of cardiopulmonary bypass. RESULTS: No difference in intraoperative blood requirement was identified between groups (18 +/- 3 cc/kg [group 1] versus 30 +/- 8 cc/kg [group 2], p = 0.16). Neither postoperative blood transfusion requirement (12 +/- 5 cc/kg [group 1] versus 16 +/- 6 cc/kg [group 2], p = 0.55) nor chest tube output in the first 24 postoperative hours (43 +/- 9 cc/kg [group 1] versus 53 +/- 13 cc/kg [group 2], p = 0.55) was significantly different between groups. Reexploration for bleeding was required in 8% (2 of 25) in group 1 and 16% (3 of 19) in group 2 (p = 0.64). CONCLUSIONS: Aprotinin reduced the amount of perioperative hemorrhage in a group of pediatric patients at high risk for bleeding after lung transplantation. The magnitude of the effect could not be quantified but was sufficient to normalize the transfusion requirement to that of a low risk group of patients.