Publications by authors named "Robert Hannan"

This manuscript details the development of an asymmetric variant for the Ni-photoredox α-arylation of tetrahydrofuran (THF), which was originally reported in a racemic fashion by Doyle and Molander. Leveraging the enantioselectivity data that we obtained, a complex mechanistic scenario different from those originally proposed is uncovered. Specifically, an unexpected dependence of the product enantiomeric ratio was observed on both the halide identity (aryl chloride vs bromide substrates) and the Ni source.

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Osteosarcomas arising within the pterygomaxillary/infratemporal fossa region are rare among the pediatric population. Survival rates are most influenced by tumor resection with negative margins, which can be dependent on surgical accessibility of the tumor site. The pterygomaxillary/infratemporal fossa location poses several challenges to safe and adequate tumor resection, including proximity of the facial nerve and great vessels and scarring associated with traditional transfacial approaches.

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  • The study aimed to assess if human fibrinogen concentrate could lower blood loss and the need for blood component therapy in neonate and infant patients undergoing cardiac surgery.
  • In a randomized trial with 30 pediatric patients, those receiving fibrinogen concentrate required significantly less cryoprecipitate than the placebo group.
  • While the treatment reduced cryoprecipitate use, it did not significantly affect overall blood loss or other measures of hemostasis and safety compared to the placebo.
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Introduction: Rotational thromboelastometry (ROTEM) has been shown to reduce the need for transfused blood products in adult and pediatric cardiac surgery patients. However, similar evidence in newborns, neonates, and young infants is lacking. We quantified ROTEM value changes in pediatric patients on cardiopulmonary bypass (CPB) before, during and after blood product transfusion.

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This study evaluated whether rotational thromboelastometry (ROTEM; Tem International GmbH, Munich, Germany) FIBTEM maximum clot firmness (MCF) can be used to predict plasma fibrinogen level in pediatric patients undergoing cardiac surgery. Linear regression was conducted to predict plasma fibrinogen level using FIBTEM MCF (0.05 level of significance).

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Background: The aim of this study was to compare three different blood washing techniques and describe the differences for the composition of the washed red blood cells (RBC).

Methods: Stored RBCs less than 5 days old were washed using three different techniques. 1) Washing with normal saline with the COBE Model 2991 blood processor in the blood bank (BB-S).

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Study Objective: To validate a non-invasive cardiac output monitor in pediatric cardiac surgery patients.

Design: Prospective trial.

Setting: Operating room.

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In infants with a single right ventricle (RV), stage I palliation involves aortic reconstruction, systemic-to-pulmonary shunt placement, and atrial septectomy. Many require re-intervention for residual coarctation of the aorta (CoA). Doppler echocardiography can detect residual CoA in most infants, but its ability to predict severity has not been studied.

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Mortality for the arterial switch operation (ASO) has diminished significantly over the past few decades. Some patients do, however, continue to have protracted and complicated courses after surgery. We attempted to determine which preoperative factors were best associated with prolonged hospital stay after ASO.

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Objective: Determine the accuracy of echocardiography to diagnose coronary anatomy in transposition of the great arteries and to evaluate the effect of accuracy on surgical outcomes and changes in accuracy over time.

Design: Retrospective chart review of neonates admitted February 1999 to March 2013 with transposition. Coronary pattern from the preoperative echocardiogram and operative reports were collected and compared with determine diagnostic accuracy.

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  • This study examined risk factors for prolonged hospital stays in children undergoing the Fontan operation for a functional single ventricle over a 15-year period.
  • Preoperative indicators such as higher hemoglobin levels, increased pulmonary artery pressure, and lower aortic saturation were linked to longer hospital stays, with hemoglobin and saturation remaining significant even after excluding certain patient groups.
  • Ultimately, the findings suggest that while most patients had stays under two weeks, specific preoperative and operative factors can lead to increased complications and extended recovery times.
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The PediBooster external cardiac compression device is a minimally invasive, non-blood contacting Biventricular Assist Device (BiVAD) intended for pediatric use. It is being developed as a palliative therapy for acute Postcardiotomy Shock (PCS). The PediBooster extracardiac wrap is pneumatically actuated to circumferentially compress the heart, providing co-pulsation support.

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This study compares four different activated clotting time (ACT) point-of-care (POC) testing systems used at our institution for the management of patients undergoing heparin therapy. We evaluated these systems under identical conditions to determine their accuracy, reproducibility, ease of use, and cost. Two separate testing stations containing four ACT systems were used.

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Our programmatic approach to the Fontan operation has evolved to include using an extracardiac conduit with aggressive presumptive treatment of associated lesions either in the catheterization laboratory or the operating room. Fenestration is used selectively based on hemodynamics, anatomy, and presence of associated lesions. We reviewed our experience to determine the effectiveness and outcome of this strategy and to assess the cumulative trauma to the patients.

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Objective: We describe a hybrid approach to the treatment of aortic obstruction after stage 1 palliation (S1P) of hypoplastic left heart syndrome.

Background: Recurrent aortic obstruction is a common problem after S1P of hypoplastic left heart syndrome. Even mild aortic obstruction is poorly tolerated so early and definitive therapy is desirable.

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Background: Tetralogy of Fallot with pulmonary atresia and diminutive or absent intrapericardial pulmonary arteries is a rare congenital abnormality, with high morbidity and mortality. Despite great advances in surgical- and catheter-based therapies, management remains challenging and controversial. We describe the surgical methods and the results from our institution.

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The management of complete heart block in premature low birth-weight infants, particularly those with hydrops fetalis, is challenging. We report emergent implantation of permanent epicardial pacemakers in the first 48 hours of life in two premature infants (one with hydrops fetalis) with birth weights of 1,400 grams and 1,000 grams.

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Objective: The purpose of this study was to evaluate the utilisation of a web-based multimedia patient-accessible electronic health record, for patients with congenital cardiac disease.

Patients And Methods: This was a prospective analysis of patients undergoing congenital cardiac surgery at a single institution from 1 September, 2006 to 1 February, 2009. After meetings with hospital administration, physicians, nurses, and patients, we configured a subset of the cardiac program's web-based clinical electronic health record for patient and family access.

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Aim: To determine the efficacy and safety of a continuous subcutaneous local anesthetic (LA) infusion in pediatric patients following open heart surgery.

Background: The use of a continuous LA infusion has been shown to be beneficial following adult cardiac surgery. To date there are no studies in the pediatric population.

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Initial palliation for pulmonary atresia with intact ventricular septum continues to evolve in the face of significant early and late morbidity. In patients with suitable anatomy, decompression of the right ventricle may be the first step in treatment. A hybrid approach to right ventricular decompression, combining surgery and interventional catheterization techniques is described.

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A 10-year-old boy with a history of renal failure and hemodialysis by indwelling superior vena cava (SVC) catheters was diagnosed with SVC obstruction and clinically severe SVC syndrome. During attempted recanalization of the SVC in the cardiac catheterization laboratory, he suffered a perforation of his SVC with pericardial tamponade. After treatment of the perforation and relief of tamponade, he underwent a hybrid procedure to recanalize his SVC.

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Intravenous administration of amiodarone has recently been recommended for use during pediatric resuscitation of pediatric patients with ventricular fibrillation or pulseless ventricular tachycardia. We present two pediatric patients who received amiodarone for polymorphic ventricular tachycardia, although they were ultimately determined to have congenital long QT syndrome. Amiodarone is contraindicated in this setting and may have exacerbated the ventricular arrhythmia.

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Background: We report a single-institution experience using a collaborative surgical and catheter-based approach to the initial treatment of pulmonary atresia with intact ventricular septum.

Methods: A retrospective review was conducted of all neonates admitted with pulmonary atresia with intact ventricular septum from 1996 to March 2007.

Results: We identified 24 patients with a mean age at first intervention of 4.

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Article Synopsis
  • Patients undergoing congenital heart surgery sometimes require additional procedures like tracheostomy and gastrostomy to reduce hospital complications and length of stay.
  • A review of medical records from Miami Children’s Hospital (2002-2007) showed that out of 1660 surgeries, tracheostomies were performed in 0.2% and gastrostomies in 0.4% of cases.
  • The low rates of these additional procedures indicate that their avoidance did not lead to more complications or longer hospital stays, suggesting good management of patients' conditions.
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