Kenneth R.T. Tyson

Management of patent ductus arteriosus: a comparison of operative v pharmacologic treatment.

Over a 5-year period ending June 1986, 183 premature infants with evidence of a hemodynamically significant patent ductus arteriosus (PDA) associated with cardiopulmonary compromise underwent pharmacologic and/or surgical ductal manipulation. One hundred seven infants underwent surgical ligation and 76 initially received indomethacin. The average birth weight was 10% less and 1 week less for the surgically treated v the indomethacin-treated infants. Among the infants undergoing ligation, there were no failures of therapy and one surgically related complication. Among the infants receiving indomethacin, 42% failed to improve, and 84% of these infants required surgical intervention. Those infants who failed indomethacin therapy in general weighed less, had a shorter gestation and required prolonged ventilatory support. In no instance was death directly attributable to either therapeutic modality. Our data suggest that surgical ligation of hemodynamically significant PDA yields a more predictable result with low morbidity and no mortality. We believe it is the preferred treatment for premature infants less than 800 g.

A prospective evaluation of intestinal stenosis following necrotizing enterocolitis

In a retrospective study, we noted a 25% incidence of colonic stenosis following medical management of necrotizing enterocolitis (NEC). From March, 1980 to March, 1982, we performed routine contrast enemas to prospectively identify the incidence of colonic stenosis following medical management for NEC. Three to four weeks following recovery from the acute phase of NEC 28 infants were prospectively evaluated by contrast enema for post-NEC stenosis. Ten of the 28 infants had one or more sites of colonic stenosis (36%). Four infants were symptomatic when the contrast enema was performed and underwent colonic resection. Three of the six asymptomatic infants developed symptoms requiring surgery within 33 days following hospital discharge. Therefore, seven of the ten infants with post-NEC stenosis required segmental colectomy. Three patients with colonic stenosis have remained asymptomatic and are being followed on an outpatient basis. The weight gain in these three infants has been steady and has paralleled a normal growth curve. The data from this study demonstrate that: (1) the incidence of post-NEC colonic stenosis is 36%; (2) patients with colonic stenosis initially may not have symptoms but may become symptomatic after hospital discharge; (3) the sites of stenosis frequently are located in the left colon; and (4) normal weight gain can occur despite the presence of colonic stenosis. Because of the above findings, we recommend routine contrast enemas in all patients with NEC who have had successful medical management.

Intestinal stenosis following successful medical management of necrotizing enterocolitis

In the past decade, increased clinical awareness and better medical and surgical management of necrotizing enterocolitis (NEC) has resulted in improved survival. With an increase in the number of infants surviving the acute stages of NEC the sequelae, including intestinal stenosis, have become more apparent. In the past 5.5 yr, 62 patients with NEC have been treated at our institution. Of the 28 survivors of medical management for NEC seven patients developed intestinal stenosis. An average of 23 days elapsed between the recovery from NEC and the diagnosis of colonic stenosis. Only three patients manifested symptoms of intestinal obstruction. Two patients had blood in their stools and two patients were asymptomatic. Five infants were managed by primary or staged resection of the intestinal stenosis. The remaining two patients were treated nonoperatively. Our data suggests a high incidence of intestinal stenosis (25%) following medical management of NEC. There is a marked preference for the stenosis to occur on the left side of the colon. Colon stenoses can exist without symptoms and radiographically proven areas of stenosis can resolve. We recommend that all infants following medical management of NEC have a barium enema prior to hospital discharge. In selected cases asymptomatic patients with colonic stenosis may not require operative intervention.

Outpatient inguinal herniorrhaphy in premature infants: is it safe?

Because postoperative apnea and bradycardia in premature infants following inguinal herniorrhaphy remains a concern, outpatient repair has not been recommended. We have been performing outpatient inguinal herniorrhaphy in premature infants and the present study reviews our experience. Between 1985 and 1990, 1,294 outpatient inguinal herniorrhaphies were performed. Of this group 124 patients (9.6%) were identified as being premature (less than or equal to 36 weeks gestational age). Average ages were: gestational age 32.7 weeks (range, 24 to 36 weeks); postnatal age 12.6 weeks (range, 3 to 24 weeks); and postconceptional age (gestational plus postnatal) 45.3 weeks (range, 34 to 59 weeks). Twenty-two infants previously required ventilatory support, 11 patients had apnea/bradycardia, and 9 patients developed bronchopulmonary dysplasia. General anesthesia (usually nitrous oxide and fluothane) was used in all patients and 75% underwent endotracheal intubation. The average operating room time was 40 minutes (range, 20 to 115 minutes) and the average recovery room time was 94 minutes (range, 30 to 240 minutes). There were no perioperative deaths. One patient became apneic immediately after extubation in the operating room. No further episodes were noted after 4 hours of observation. Another patient following discharge had a brief apneic episode at home while on an apnea monitor, which was relieved with gentle stimulation. Both patients had no further sequelae. Bradycardia to 80 beats/min was noted in two patients, and resolved spontaneously in the recovery room. Laryngospasm after extubation in the operating room occurred in two patients, one of whom required brief reintubation and the other resolved spontaneously. Two patients required postoperative ventilation: one was extubated in the recovery room and the other was hospitalized for 24 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary repair of esophageal atresia without staging or preliminary gastrostomy.

Twenty-two neonates with esophageal atresia and a distal tracheoesophageal fistula were treated by primary repair. Only if an anastomotic leak was demonstrated was a tube gastrostomy for decompression with trangastric placement of a duodenal tube for feeding performed. Twelve newborns were classified as high-risk by the presence of prematurity with low birth weight (less than 2,250 gm), significant pneumonia, or obvious significant associated anomalies. There was one operative death and 1 late death. Three babies required a tube gastrotomy and duodenal tube for anastomotic leaks. All 20 survivors are symptom free and thriving. Progress in perioperative management of neonates with esophageal atresia may obviate the need for routine gastrostomy and for staging of high-risk newborns.

The Surgical Significance of Aberrant Renal Arteries in Relation to Systemic Hypertension

Three cases of hypertension associated with vascular insufficiency of aberrant renal arteries are presented. Two patients were subjected to revascularization procedures. The types of pathologic processes associated with aberrant renal arteries in production of segmental renal ischemia are discussed. Considerations of diagnosis and therapy of such lesions are reviewed.

Effect of blood viscosity on pulmonary vascular resistance

Abstract In the treatment of congenital cyanotic heart disease, the effectiveness of palliative shunts between the systemic arterial or systemic venous circulation and the pulmonary arterial circulation is dependent in no small part upon resistance to pulmonary blood flow. Factors that increase pulmonary vascular resistance tend to decrease the volume flow to the lungs by way of these shunts, and hence, to decrease their effectiveness. It has long been known that increased blood viscosity increases systemic vascular resistance and, secondarily, decreases total cardiac output in the intact circulation. 1 Similar changes of increased pulmonary vascular resistance have been seen when blood viscosity is increased; but since increased pulmonary vascular resistance occurs in the face of diminished cardiac output for whatever cause, it is not known whether increased blood viscosity is a primary factor in increasing resistance in the pulmonary circulation or if the increased pulmonary vascular resistance observed is a consequence only of diminished cardiac output. Since the functional effectiveness of systemic arterial or venous-pulmonary artery shunts is dependent primarily upon pulmonary vascular resistance, it seems important to determine what effect changes in blood viscosity have on pulmonary vascular resistance independent of changes in cardiac output.

Coarctation of the abdominal aorta: Etiologic considerations in surgical management

Summary Three cases of segmental coarctation of the abdominal aorta with involvement of the renal arteries treated by prosthetic revascularization are presented. Two of the patients are normotensive one and seven years postoperatively. The third is asymptomatic although moderately hypertensive without antihypertensive therapy. Histologic examination of involved vessels in two of the cases show no indication of an inflammatory origin for the lesions. It is suggested that most abdominal coarctations seen in children and young adults in the United States are of a developmental origin and may be treated successfully by revascularization.

The Blalock-Taussig Shunt in the First Two Years of Life: A Safe and Effective Procedure

Many surgeons have been reluctant to perform Blalock shunts in patients who are in infancy or early childhood (less than 24 months old) and have done instead direct aortopulmonary anastomoses. Recently, others have advocated complete repair of tetralogy of Fallot in early infancy because of the high mortality of direct aortopulmonary shunts. We believe the Blalock-Taussig anastomosis is a safe and effective palliative procedure for all infants with inadequate pulmonary blood flow regardless of size. During the past nine years, 24 babies less than 2 years old who were followed had construction of Blalock-Taussig anastomosis for inadequate pulmonary blood flow. There were no operative deaths and no shunt-related late deaths. Of the 24 babies, 12 were less than 12 months old. Eighteen of the 24 had tetralogy of Fallot. The remaining 6 had a variety of lesions with inadequate pulmonary blood flow. The mean weight of the entire group was 7.3 +/- 1.6 kg. Of those infants less than 12 months old, the mean weight was 6.8 +/- 2.0 kg. More than 6 months following construction of the shunt, 2 babies died from sepsis unrelated to cardiovascular status. All infants had adequate but not excessive pulmonary blood flow after shunting. There were no late shunt failures.

Congenital idiopathic hypertrophic subaortic stenosis associated with a phenotypic Turner's syndrome☆

Abstract A case of idiopathic hypertrophic subaortic stenosis in a girl with phenotypic Turners syndrome is reported. The coincidence of these rare anomalies, reported only once before, is unlikely to occur by chance. Essential clinical features leading to early diagnosis of idiopathic hypertrophic subaortic stenosis in infancy are presented. Surgical treatment when the child weighed 15.9 kg gave satisfactory results at 18-month follow-up study.