Low-dose prostaglandin E1 is safe and effective for critical congenital heart disease: is it time to revisit the dosing guidelines?

INTRODUCTION: Prostaglandin E1 is used to maintain ductal patency in critical congenital heart disease (CHD). The standard starting dose of prostaglandin E1 is 0.05 µg/kg/minute. Lower doses are frequently used, but the efficacy and safety of a low-dose regimen of prostaglandin E1 has not been established. METHODS: We investigated neonates with critical CHD who were started on prostaglandin E1 at 0.01 µg/kg/minute. We reviewed 154 consecutive patients who were separated into three anatomical groups: obstruction to systemic circulation, obstruction to pulmonary circulation, and inadequate mixing (d-transposition of the great arteries). Treatment failure rates and two commonly reported side effects, respiratory depression and seizure, were studied. RESULTS: A total of 26 patients (17%) required a dose increase in prostaglandin E1. Patients with pulmonary obstruction were more likely to require higher doses than patients with systemic obstruction (15/49, 31% versus 9/88, 10%, p = 0.003). Twenty-eight per cent of patients developed respiratory depression and 8% of patients needed mechanical ventilation. Prematurity (<37 week gestation) was the primary risk factor for respiratory depression. No patient required dose escalation or tracheal intubation while on transport. No patient had a seizure attributed to prostaglandin E1. CONCLUSIONS: Prostaglandin E1 at an initial and maintenance dose of 0.01 µg/kg/minute was sufficient to maintain ductal patency in 83% of our cohort. The incidence of respiratory depression requiring mechanical ventilation was low and was mostly seen in premature infants. Starting low-dose prostaglandin E1 at 0.01 µg/kg/minute is a safe and effective therapy for critical CHD.

Lymphatic Management in Single-Ventricle Patients.

Lymphatic complications in patients with single ventricle include plastic bronchitis, protein-losing enteropathy, and chylous pleural effusion are a source of significant morbidity and mortality with historically limited therapeutic options. Novel lymphatic imaging techniques such as intranodal lymphangiography, dynamic contrast enhanced magnetic resonance lymphangiography and liver lymphangiography have allowed visualization of the lymphatic system and discovery of the pathophysiological mechanism of these conditions. This mechanism includes the combination of 2 factors: increased lymphatic flow in patients with elevated central venous pressure and presence of the lymphatic anatomical variant that allows the lymph to flow in close proximity to the serous (pleural space in chylothorax) or mucosal (plastic bronchitis and protein losing enteropathy) surfaces. Novel minimally invasive lymphatic interventional techniques, such as thoracic duct embolization, interstitial embolization and liver lymphatic embolization have allowed the obliteration of these abnormal lymphatic networks, resulting in resolution of the symptoms. Further refinement of the imaging techniques and interventional methods have subsequently allowed better patient selection and improved long term outcome of these procedures.

Emergent Interhospital Transport of Pediatric Patient With a Berlin Heart Device.

Ventricular assist devices (VADs) for the mechanical support of cardiac failure are being used more frequently in children of increasingly younger age. These children have significant and multiple medical comorbidities, and their length of hospital stay has been increasing. As this population of hospitalized VAD-supported children increases, so does the possibility of their need for interfacility transport for specialized diagnostic or therapeutic procedures. Reports on such transports are limited to 3 children who underwent scheduled elective transfers. We report our experience with a child with a Berlin Heart EXCOR left ventricular assist device (Berlin Heart, Berlin, Germany) who required emergent interfacility transport between our hospital and an affiliated institution.

Relationship between alveolar functional fraction and clinical outcomes in children during postoperative care after surgery for single-ventricular heart.

Background: Optimization of pulmonary to systemic blood flow (Qp: Qs) is the key to postoperative care of children with a single-ventricular heart. The ratio of end-tidal CO2 to partial pressure of CO2 called alveolar functional fraction (AFF) has shown a strong relationship with Qp: Qs in the catheterization lab in this population (with Qp: Qs of 1 correlating with AFF of 0.7). As there are no studies to understand the relationship between AFF and clinical outcomes in the postoperative care of these children, this study was carried out. Methodology and Results: This retrospective cohort study included 29 postoperative periods of children who underwent surgery for a single-ventricular heart. The average AFF was calculated for each early postoperative period. The primary clinical outcome was time in hours to normalize lactate. Other clinical outcomes included duration of mechanical ventilation, duration of milrinone infusion; presence of acute kidney injury (AKI), seizures and necrotizing enterocolitis (NEC); need for tracheostomy, need for extra-corporeal support, and mortality in the first 60 days postoperatively. The study population was divided into Group 1 with AFF ≤0.7 and Group 2 with AFF >0.7, to compare the outcome differences between the groups. Time to normalize the lactate had a modest negative correlation with the AFF, with Pearson's r = -0.49 (P = 0.007) for the entire cohort. The clinical outcomes were not statistically different for groups with AFF ≤0.7 and with AFF >0.7, although the group with AFF ≤0.7 had a higher incidence of NEC and higher mortality, whereas the group with AFF >0.7 had a higher incidence of AKI. Conclusions: In this small study, the AFF showed a modest negative correlation with the time to normalize lactate in postoperative care after surgery for a single-ventricle heart. There were the trends with some other important clinical outcomes but not statistically significant. A larger, multi-center study is needed to delineate these relationships further.

Surgical Reconstruction for Severe Tracheal Obstruction in Morquio A Syndrome.

Progressive tracheal obstruction is commonly seen in Morquio A syndrome and can lead to life-threatening complications. Although tracheostomy can address severe upper airway obstruction, lower airway obstruction, commonly associated with a narrow thoracic inlet and vascular compression, requires an alternative approach. We describe the case of a 16-year-old patient with Morquio A syndrome whose near-fatal tracheal obstruction was relieved by timely surgical tracheal vascular reconstruction with dramatic resolution of his respiratory symptoms.

Scoliosis surgery in children with congenital heart disease.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To describe preoperative evaluation, anesthetic and perioperative management, and complications in patients with congenital heart disease (CHD) who underwent surgery to correct a spine deformity. SUMMARY OF BACKGROUND DATA: Patients with surgically palliated or repaired CHD may have nearly normal circulation or may have important residual abnormalities that affect the planning and conduct of surgery to correct a spine deformity. METHODS: We examined the records of 21 patients with spine deformity who had previous surgical intervention for CHD. Three types of spine surgery and instrumentation were examined, posterior spinal fusion with instrumentation (PSFI), growing rod (GR) instrumentation, and vertical expandable prosthetic titanium rib instrumentation (VEPTR). To objectify the degree of preoperative cardiac physiological derangement, patients were classified into 3 groups: single ventricle physiology and Fontan circulation (S), two ventricles with no residual abnormal cardiac physiology condition (2N), and two ventricles with residual cardiac physiology problem (2R). RESULTS: Subjects were 8 boys and 13 girls with mean age of 11.1 ± 5.2 years. Sixteen patients underwent surgery to correct scoliosis, 1 to correct kyphosis, and 4 did not undergo surgery. Total number of surgical procedures was 23 (16 PSFI, 5 GR, and 2 VEPTR). On the basis of cardiac physiology, 2 patients belonged 2N, 11 were 2R, and 8 were group S. Mean estimated blood loss was 1685 mL during PSFI, 515 mL during GR, and 150 mL during VEPTR. Mean volume of blood transfusion was 44 mL/kg for PSFI, 19 mL/kg for GR, whereas no transfusion was administered during VEPTR. Median intensive care unit stay was 2 days ranging from hours to 78 days. Median hospital length of stay was 7 days ranging from 3 to 93 days. There were no deaths. CONCLUSION: Given meticulous multidisciplinary planning and execution, major spine surgery can be safely and successfully performed in patients with significant residua of CHD. LEVEL OF EVIDENCE: 4.

Risk factors for hospital morbidity and mortality after the Norwood procedure: A report from the Pediatric Heart Network Single Ventricle Reconstruction trial.

OBJECTIVES: We sought to identify risk factors for mortality and morbidity during the Norwood hospitalization in newborn infants with hypoplastic left heart syndrome and other single right ventricle anomalies enrolled in the Single Ventricle Reconstruction trial. METHODS: Potential predictors for outcome included patient- and procedure-related variables and center volume and surgeon volume. Outcome variables occurring during the Norwood procedure and before hospital discharge or stage II procedure included mortality, end-organ complications, length of ventilation, and hospital length of stay. Univariate and multivariable Cox regression analyses were performed with bootstrapping to estimate reliability for mortality. RESULTS: Analysis included 549 subjects prospectively enrolled from 15 centers; 30-day and hospital mortality were 11.5% (63/549) and 16.0% (88/549), respectively. Independent risk factors for both 30-day and hospital mortality included lower birth weight, genetic abnormality, extracorporeal membrane oxygenation (ECMO) and open sternum on the day of the Norwood procedure. In addition, longer duration of deep hypothermic circulatory arrest was a risk factor for 30-day mortality. Shunt type at the end of the Norwood procedure was not a significant risk factor for 30-day or hospital mortality. Independent risk factors for postoperative renal failure (n = 46), sepsis (n = 93), increased length of ventilation, and hospital length of stay among survivors included genetic abnormality, lower center/surgeon volume, open sternum, and post-Norwood operations. CONCLUSIONS: Innate patient factors, ECMO, open sternum, and lower center/surgeon volume are important risk factors for postoperative mortality and/or morbidity during the Norwood hospitalization.