Redmond P. Burke

Perioperative effects of alpha-stat versus pH-stat strategies for deep hypothermic cardiopulmonary bypass in infants.

OBJECTIVES In a randomized, single-center trial, we compared perioperative outcomes in infants undergoing cardiac operations after use of the alpha-stat versus pH-stat strategy during deep hypothermic cardiopulmonary bypass. METHODS Admission criteria included reparative cardiac surgery, age less than 9 months, birth weight 2.25 kg or more, and absence of associated congenital or acquired extracardiac disorders. RESULTS Among the 182 infants in the study, diagnoses included D-transposition of the great arteries (n = 92), tetralogy of Fallot (n = 50), tetralogy of Fallot with pulmonary atresia (n = 6), ventricular septal defect (n = 20), truncus arteriosus (n = 8), complete atrioventricular canal (n = 4), and total anomalous pulmonary venous return (n = 2). Ninety patients were assigned to alpha-stat and 92 to pH-stat strategy. Early death occurred in four infants (2%), all in the alpha-stat group (p = 0.058). Postoperative electroencephalographic seizures occurred in five of 57 patients (9%) assigned to alpha-stat and one of 59 patients (2%) assigned to pH-stat strategy (p = 0.11). Clinical seizures occurred in four infants in the alpha-stat group (4%) and two infants in the pH-stat group (2%) (p = 0.44). First electroencephalographic activity returned sooner among infants randomized to pH-stat strategy (p = 0.03). Within the homogeneous D-transposition subgroup, those assigned to pH-stat tended to have a higher cardiac index despite a lower requirement for inotropic agents; less frequent postoperative acidosis (p = 0.02) and hypotension (p = 0.05); and shorter duration of mechanical ventilation (p = 0.01) and intensive care unit stay (p = 0.01). CONCLUSIONS Use of the pH-stat strategy in infants undergoing deep hypothermic cardiopulmonary bypass was associated with lower postoperative morbidity, shorter recovery time to first electroencephalographic activity, and, in patients with D-transposition, shorter duration of intubation and intensive care unit stay. These data challenge the notion that alpha-stat management is a superior strategy for organ protection during reparative operations in infants using deep hypothermic cardiopulmonary bypass.

Surgical treatment of adult atrial septal defect: Early and long-term results

OBJECTIVES The purpose of this study is to determine the early and late results of the surgical repair of atrial septal defect in adults. BACKGROUND Progressively limiting, untreated atrial septal defect can lead to the early death of middle-aged adults. Recently it has been suggested that the closure of atrial septal defects might be accomplished with interventional cardiac techniques. Although the long-term results of the transcatheter closure are as yet unknown, the outcome of surgical therapy has been shown to be beneficial for almost 40 years. METHODS Between 1971 and 1991, 166 consecutive patients underwent surgical repair of a secundum or sinus venosus atrial septal defect, or both, at the Brigham and Womens Hospital, Boston. There were 120 women and 46 men in this group; the mean age was 44 years and 58 (35%) of the patients were > or = 50 years old. The average pulmonary to systemic flow ratio was 3.0, and 57 patients had a peak systolic pulmonary artery pressure > 30 mm Hg. RESULTS There were two operative deaths (early mortality rate 1.2%), and 13% of the patients had a perioperative complication. One hundred fifty-three of the 164 survivors were followed up for a mean of 90 months (range 2 to 247). There were eight late deaths (late mortality rate 4.9%) and a late morbidity rate of 12.4% (in most cases due to arrhythmias). The 5- and 10-year survival rates are 98% and 94%, respectively, and the probability of event-free survival (with no morbidity or mortality) at 5 years is 97% and at 10 years is 92%. CONCLUSIONS The results indicate that the surgical correction of atrial septal defect in adults is safe and efficacious as confirmed by 20 years of follow-up.

Outcome of cardiopulmonary resuscitation in a pediatric cardiac intensive care unit.

ObjectiveTo determine the eventual outcome of children with heart disease who had cardiopulmonary resuscitation (CPR) in a specialized pediatric cardiac intensive care unit (CICU), and to define the influence of any prearrest variables on the outcome. DesignA retrospective review of patients’ medical records. SettingA pediatric CICU of a tertiary pediatric teaching hospital. Patients and MethodsPatients were all children who presented with cardiopulmonary arrest and who were administered CPR in the pediatric CICU between June 1995 and June 1997. Prearrest variables such as age, diagnosis, prior cardiac surgery, and inotropic support with epinephrine, as well as cause of arrest, were evaluated. Measurements and Main ResultsThirty-two patients, ranging in age from 1 day to 21 yrs (median, 1 month), satisfied criteria for inclusion in the study group. These 32 patients had a total of 38 episodes of cardiopulmonary arrest. Twenty-five of these patients (78%) had cardiac surgery before arrest. Inotropic support with continuous infusion of epinephrine was being administered at the time of arrest in 18 of 38 (47%) arrests. These prearrest variables did not influence outcome of CPR.Of the 38 episodes of CPR, 24 episodes (63%) were successful, with 20 episodes resulting in return of spontaneous circulation and four patients being successfully placed on mechanical cardiopulmonary support. Fourteen children, including all four patients who were rescued with mechanical cardiopulmonary support, survived to discharge. At 6-month follow-up, 11 patients were still alive, with three having neurologic impairment. ConclusionsAfter cardiopulmonary resuscitation in this pediatric CICU, the rate of success was 63% and the rate of survival was 42%. Prior cardiac surgery and use of epinephrine before arrest did not influence the outcome of CPR. The availability of effective mechanical cardiopulmonary support can improve the outcome of CPR.

Video-assisted thoracoscopic surgery for congenital heart disease

Video-assisted endoscopic techniques have reduced operative trauma in adult thoracic and general surgery, but applications in children with congenital heart disease have been limited. We report the development of video-assisted thoracic surgery procedures for neonates and infants with cardiovascular disease. Endoscopic instruments and techniques for pediatric cardiovascular procedures were designed and tested in the animal laboratory. Forty-eight operations were subsequently performed in 46 pediatric patients ranging in age from 2 hours to 14 years (median 9 months), weighing from 575 grams to 54 kg (median 8.5 kg). Clinical applications included seven different surgical procedures: patent ductus arteriosus interruption in infants (n = 26) and premature neonates (n = 5), vascular ring division (n = 8), pericardial drainage and resection (n = 3), arterial and venous collateral interruption (n = 2), thoracic duct ligation (n = 2), epicardial pacemaker lead insertion (n = 1), and diagnostic thoracoscopy (n = 1). There was no operative mortality. Technical success, defined as a video-assisted procedure completed without incising chest wall muscle or spreading the ribs, was achieved in 39 of 48 procedures (82%), with thoracotomy required to complete nine procedures. Most patients (22/25, 88%) undergoing elective ductus ligation were extubated in the operating room and discharged from the hospital within 48 hours of the operation. Eight of the last 10 patients having ductus ligation were discharged on the first postoperative day. Residual ductal flow was assessed by (1) transesophageal echocardiography in the operating room (incidence: 0/25, 0%, 70% CL 0% to 7.3%); (2) discharge auscultation (incidence: 1/30, 3%, 70% CL 0.5% to 10.8%); and (3) follow-up Doppler echocardiography (incidence: 3/25, 12%, 70% CL 5.4% to 22.6%). Video-assisted thoracoscopic techniques can be safely applied to pediatric patients with patent ductus arteriosus and vascular rings and may become an effective addition to the staged management of more complex forms of congenital heart disease.

Coronary artery abnormalities detected at cardiac catheterization following the arterial switch operation for transposition of the great arteries

Because the arterial switch operation has become the routine surgical approach for transposition of the great arteries, there is increasing awareness of adverse sequelae in some survivors. For the arterial switch to be considered the procedure of choice for transposition of the great arteries, long-term patency and normal function of the translocated coronary arteries must be achieved. We reviewed the cineangiograms and hemodynamic data in 366 patients who underwent postoperative catheterization after arterial switch operation. Of these, 13 patients (3%) had previously unsuspected coronary abnormalities diagnosed angiographically. No patient had noninvasive evidence of resting systolic dysfunction. Findings included left main coronary artery stenosis (n = 3) or occlusion (n = 2), anterior descending coronary artery stenosis (n = 1) or occlusion (n = 2), right coronary artery stenosis (n = 1) or occlusion (n = 1), and small coronary artery fistulas (n = 3). One patient died suddenly 3.3 years after surgery, 1 patient is lost to follow-up, and the remaining 10 patients are alive and asymptomatic up to 11 years after surgery.

Congenital Heart Surgery Nomenclature and Database Project: ventricular septal defect

The extant nomenclature for ventricular septal defect (VSD) is reviewed for the purpose of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include all relevant nomenclature categories using synonyms where appropriate. Four basic VSD types are described: Subarterial, Perimembranous, Inlet, and Muscular. A comprehensive database set is presented which is based on a hierarchical scheme. Data are entered at various levels of complexity and detail which can be determined by the clinician. These data can lay the foundation for comprehensive risk stratification analysis. A minimum database set is also presented which will allow for data sharing and would lend itself to basic interpretation of trends. Outcome tables relating diagnoses, procedures, and various risk factors are presented.

Tracheal allograft reconstruction: the total North American and worldwide pediatric experiences

BACKGROUND We reviewed both the North American and the total worldwide pediatric experience with tracheal allograft reconstruction as treatment for patients with long segment and recurrent tracheal stenosis. METHODS The stenosed tracheal segment is opened to widely patent segments. The anterior cartilage is resected and the posterior trachealis muscle or tracheal wall remains. A temporary silastic intraluminal stent is placed and absorbable sutures secure the chemically preserved cadaveric trachea. After initial success with this technique in Europe, several North American centers have now performed the procedure. The cumulative North American experience includes 6 patients (3 adults and 3 children). Worldwide, more than 100 adults and 31 children, aged 5 months to 18 years, with severe long segment tracheal stenosis have undergone tracheal allograft reconstruction. RESULTS In North America, 5 of 6 patients have survived, with one early death due to bleeding from a tracheal-innominate artery fistula in a previously irradiated neck. Worldwide, 26 children survived (26 of 31 = 84%) with follow-up from 5 months to 14 years. Only 1 of 26 pediatric survivors (1 of 26 = 3.8%) had a tracheostomy. CONCLUSIONS Tracheal allograft reconstruction demonstrates encouraging short- to medium-term results for patients with complex tracheal stenosis. Allograft luminal epithelialization supports the expectation of good long-term results.

Congenital Heart Surgery Nomenclature and Database Project: aortopulmonary window

The extant nomenclature for aortopulmonary window (AP window) and pulmonary artery origin from ascending aorta (hemitruncus) is reviewed for the purpose of establishing a unified reporting system. The subject was debated and reviewed by members of the STS-Congenital Heart Surgery Database Committee and representatives from the European Association for Cardiothoracic Surgery. All efforts were made to include all relevant nomenclature categories using synonyms where appropriate. A comprehensive database set is presented that is based on a hierarchical scheme. Data are entered at various levels of complexity and detail that can be determined by the clinician. These data can lay the foundation for comprehensive risk stratification analyses. A minimum database set is also presented that will allow for data sharing and would lend itself to basic interpretation of trends. Outcome tables relating diagnoses, procedures, and various risk factors are presented.

Rapid cardiopulmonary support for children with complex congenital heart disease

BACKGROUND Extracorporeal membrane oxygenation has limitations in children with congenital heart disease (prolonged setup times, increased postoperative blood loss, and difficulty during transport). We developed a miniaturized cardiopulmonary support circuit to address these limitations. PATIENTS AND METHODS The cardiopulmonary support system includes a preassembled, completely heparin-coated circuit, a BP-50 Bio-Medicus centrifugal pump, a Minimax plus membrane oxygenator, a Bio-Medicus flow probe, and a Bio-trend hematocrit/oxygen saturation monitor. Short tubing length permits a 250-mL bloodless prime in less than 5 minutes. From 1995 to 1997, 23 children with congenital heart disease were supported with this technique. RESULTS Overall survival to discharge was 48% (11 of 23 patients). Survival to discharge was 80% (4 of 5) in the preoperative support group, 20% (1 of 5) in the postoperative failure to wean from cardiopulmonary bypass group, 44% (4 of 9) in the group placed on support postoperatively after transfer to the intensive care unit, and 50% (2 of 4 patients) in the nonoperative group. Neonatal cardiopulmonary support survival to discharge was 46% (6 of 13 patients). CONCLUSIONS This pediatric cardiopulmonary support system is safe and effective. Advantages over conventional extracorporeal membrane oxygenation include rapid setup time, decreased postoperative blood loss, and simplified transport.

Video-assisted thoracoscopic surgery for patent ductus arteriosus in low birth weight neonates and infants.

Background. Video-assisted thoracoscopic surgery (VATS) has been assuming an expanded role in the management of cardiothoracic disease. As instrumentation and experience increase, VATS is being applied to treat smaller patients. We report our experience with 34 low birth weight infants undergoing VATS interruption of patent ductus arteriosus (PDA). Methods. VATS allows PDA interruption without the muscle cutting or rib spreading of a standard thoracotomy. Four small, 3-mm incisions are made along the line of a potential thoracotomy incision. Ports placed through these incisions admit endoscopic instruments, a camera, and a vascular clip applier. Results. Median age at surgery was 15.5 days (range: 1–44 days). Median weight at surgery was 930 g (range: 575-2500 g). Twenty patients weighed <1 kg, and 13 weighed <750 g. All patients had congestive heart failure and had either failed indomethacin therapy or had contraindications to indomethacin. Median surgical time was 60 minutes (range: 31–171 minutes). Echocardiography documented elimination of ductal flow in all patients. Operative mortality was zero. Four patients (4/34 = 12%) required conversion to open thoracotomy: 1 because of difficult exposure, 1 because of pulmonary dysfunction and anasarca, 1 because of a large 1-cm duct, and 1 because of coagulopathy and poor pulmonary compliance. Two patients died before discharge: 1 patient (surgical weight: 605 g) died on postoperative day 2 because of intracranial hemorrhage, and 1 patient (surgical weight: 1725 g) died on postoperative day 88 because of multiple system organ failure. Follow-up has demonstrated no PDA murmur in any patient, but echocardiography revealed trace ductal flow in 2 patients. Conclusions. VATS offers a minimally traumatic, safe, and effective technique for PDA interruption in low birth weight neonates and infants.