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Biomedical subjects

J S Simpson

Publications and source records attributed to J S Simpson.

At least 55 records · Page 3Linked to original sources
PubMed1981

Automated two-site immunoradiometric assay of human alpha-fetoprotein in maternal serum.

Immunoassays of alpha 1-fetoprotein in maternal serum are now in widespread use as a means of antenatal detection of neural tube defects. For population screening to be effective the initial test must be capable of promptly producing reliable results. We describe an automated two-site immunoradiometric assay based on 125I-labeled antibodies and cellulose-coupled antibody, with which up to 100 patients' samples can be assayed in 3 h. The assay is precise, and results obtained agree closely with those produced by conventional radioimmunoassay procedures.

Autoanalysis↗
PubMed1981

Wide gap esophageal atresia with inaccessible upper pouch.

Circular myotomy of the proximal esophageal pouch has allowed end-to-end esophagoesophagostomy in infants with wide gap esophageal atresia. Occasionally, the proximal pouch ends so high in the thorax that the circular myotomy is technically impossible under conventional means. Exteriorization, mobilization, and myotomy of the proximal esophageal pouch via a separate cervical incision has allowed us to overcome this limitation of an inaccessible upper pouch and has permitted esophagoesophagostomy. This technique has been performed successfully in two infants with good results and no morbidity over a follow-up period of 1 1/2 to 3 1/2 years.

Esophageal Atresia↗
PubMed1980

Long-term follow-up circular myotomy for esophageal atresia.

Between January 1976 and March 1979, esophageal atresia was successfully repaired in six infants with circular myotomy (Livaditis technique) and end-to-end anastomosis. Children were 1 day-6 mo in age and weighed 2.4 to 8.0 kg at the time of repair. Four children required one and two children required two circular myotomies in the proximal esophagus to bridge gaps between esophageal ends, which varied from 1.2-3.0 cm. Follow-up has been 1-4 yr (mean-3 yr). Operative complications included: opening of the mucosa at myotomy (2) and anastomotic leak (2). Subsequently, three children developed anastomotic stricture which required dilatation. Current x-rays show ballooning of the esophagus at the myotomy site during swallowing in all. However, the esophageal diameter at the myotomy site was never more than 2 cm greater than that of the distal esophagus. In the three children with anastomotic stricture, mucosal ballooning was not greater than in the others. During follow-up, weights have ranged from the 3rd to the 50th percentile for age. Swallowing has been good in 4, fair in 1 (dilatation still required), and poor in 1 (oropalatal deformities necessitate gastrostomy feedings). Circular myotomy offers a safe means of esophageal lengthening. Complications directly related to the myotomy are minimal (mucosal tear) and should be recognized at operation. Ballooning of the mucosa at the myotomy site is a common late finding but diverticulum formation has not occurred. Swallowing and esophageal motility are similar to other children who have had esophageal atresia repair.

Esophageal Atresia↗
PubMed1980

The pharmacologic treatment of newborn diaphragmatic hernia--a 2-year evaluation.

From 1968 to 1976 inclusive, 69 neonates with diaphragmatic hernias had corrective surgery within 18 hr of birth and the survival rate was 41%. During the same time, all babies with similar hernias who were operated on later than 18 hr from the time of birth survived. Our present interest has been focused on the pulmonary artery and its hypertension with the subsequent development of right to left shunting through the patent ductus arteriosus. During 1977 and 1978, we attempted to enter 19 consecutive newborns 18 hr of age or less with symptomatic Bochdalek diaphragmatic hernias into a "Collins protocol" for treatment. This included four stages: newborn nursery initial resuscitation, operation, cardiac catheterization, and ICU monitoring and pharmacological therapy. There was a total of seven survivors (36%), however for a number of reasons only eight babies really had a complete entry into this protocol and of these eight, five survived. Although this study is far from complete, some initial information and concepts are forthcoming. It is now apparent to us that there are three distinct groups into which these very early newborns fall: minimal pulmonary hypoplasia, unilateral hypoplasia and bilateral hypoplasia. The first group probably does not need pharmacologic support, while in the last it probably does not help. Further interest in other more specific pulmonary pharmacologic agents is now being considered as well as some way of early recognition of which baby is going to fit into which group, so that only the ones that need this treatment will get it.

Acetylcholine↗
PubMed1980

Nonsurgical management of appendiceal mass in late presenting children.

Thirty-seven late presenting children with appendiceal mass were treated between 1965 and 1975 with i.v. fluids, alimentation according to the state of gastrointestinal function, and no antibiotics. They ranged in age from 18 mo to 16 yr and all had had symptoms for at least 5 days (mean 8.7), an abnormal WBC (mean 19.9), and a fixed palpable mass without rebound tenderness. Children were discharged when clinical findings resolved. All returned for interval appendectomy. Eighty-one percent (31 children) had clinical improvement within 5-22 days (mean 10.9). Nineteen percent (7 children) had recurrence or worsening of symptoms and required abscess drainage within 2-10 days after observation began. No child in either group received antibiotics nor did any die. Only one recurrence of symptoms after discharge was recorded before interval appendectomy. Pathologic specimens revealed fibrosis in 46%, subacute inflammation in 35%, and acute inflammation in 19%. Nonoperative management of the appendiceal mass without antibiotics in children is safe as long as diligent observation is maintained. Interval appendectomy can be performed as late as 20 wk after symptom resolution or drainage, however, over 50% of the interval appendectomy specimens reveal acute and subacute inflammation.

Adolescent↗
PubMed1979

The value of emergency open lung biopsy in infants and children.

The records of 36 infants and children who underwent emergency open lung biopsy at the Hospital for Sick Children, Toronto, between 1969 and 1976 were studied in order to assess the safety and value of performing this procedure in patients with failing respiratory function. Prior to their respiratory illness, 14 of these patients were receiving steroids, chemotherapy, and radiotherapy singly or in combination as treatment for various sytemic diseases of which leukemia was the most prominent. In all cases the biopsy was performed under general anesthesia and lasted about 1 hour. The biopsy was diagnostic in all but one of these children, permitting the institution of appropriate therapy. Six preventible postoperative complications required treatment but there were no deaths attributable to operation in this series. Emergency open lung biopsy is strongly recommended even in patients in severe respiratory failure when all routine investigations fail to yield a diagnosis.

Adolescent↗
PubMed1979

Partial gastric wrap-around as an alternative procedure in the treatment of hiatal hernia.

The Allison, Belsey, and Nissen antireflux operations have been widely used over the last 15 yr. A number of problems have followed from these procedures that have prompted us under certain circumstances to seek alternative operations. In the last 2 yr, in selected patients, we have done a partial gastric wrap-around (Dor-Nissen) operation on 16 children from age 2 wk to 13 yr for the following reasons: failed Allison and Nissen repairs, two infants with such a small stomach that only a partial stomach wrap-around was possible, with a Heller cardiomyotomy, and for reflux with or without an accompanying hiatal hernia. All of these Dor-Nissen partial wrap-around operations were technically easy to do and all the postoperative patients have been problem-free both clinically and radiologically. Moreover, the gass bloat syndrome seen with the Nissen fundoplication has not been encountered. We recommended this partial wrap-around antireflux operation as a primary procedure, an alterative to one of the more widely used operations, or when re-operating for recurrence of gastroesophageal reflux.

Adolescent↗
PubMed1979

Perforated stress ulcer in infants: a silent threat.

Stress ulcer has become an important clinical entity and its two major complications--bleeding and perforation--are among the most baffling problems, in terms of management, in clinical practice. Perforation, though the less common of the two, is perhaps the most formidable particularly when this occurs in a very sick infant. Four such infants (cyanotic heart disease, gastroenteritis and two severe pneumonias) all developed this severe complication of their illness and after surgery two survived. Two of these infants presented with bleeding prior to perforation of their stress ulcer. The perforation diagnosis was initially not apparent and was first made after radiological examination. Clinical signs of peritonitis were absent as these infants were too sick for such signs to be elicited. All four ulcers were situated in the posterior wall of the duodenum. Two of these infants developed cardiac complications on the operating table, the cause of which was not very clear. It may have been due to the debilitation of these babies with the additional effect of anesthesia perhaps leading to myocardial toxicity. It is therefore recommended that: all sick infants on steroid therapy be placed on prophylactic antacids; abdominal girth measurements be taken frequently in sick infants to appreciate any unexplained increase in girth; such increase in abdominal girth must be evaluated with an upright abdominal x-ray; operative closure of the perforation must be simple and expedient.

Duodenal Ulcer↗
PubMed1978

Assessment of the cardiovascular system in conjoined thoracopagus twins.

The thoracoomphalopagus conjoined twins comprise 75% of all conjoined twins. In the assessment of the organ systems of the twins, the cardiovascular system is important since union of this system in the twins has occurred in 75% of the cases. Of the five cases reported here, two had separate hearts and vessels with a common pericardium only. Two twins were joined at the right atrial level. The fifth pair were connected at both atrial and ventricular levels. It has been suggested that the presence of two separate QRS complexes in the ECG indicates complete separation of the two hearts. Case 4 shows that even in the presence of atrial union, the existence of an atrioventricular block in one twin may produce a very slow heart rate, while the other twin may have a normal rate that will not influence the ventricular rate of the other. In our experience, angiocardiography has been the most useful diagnostic procedure.

Angiocardiography↗
PubMed1978

Nonoperative management of traumatized spleen in children: how and why.

In the absence of the apleen, overwhelming infection is a real threat. Therefore, there is a trend to try to preserve all spleens. Recognizing this, and realizing that not every damaged spleen must be removed, a nonoperative approach has been advocated and practiced for 35 yr at the Hospital for Sick Children in Toronto. This experience is recorded herein, providing indications and methods of management. The results are considered to be very satisfactory.

Blood Transfusion↗
PubMed1978

Fourteen years of gastric tubes.

Since 1964 gastric tube replacement of the esophagus has been done in 30 infants and children. This report reviews and brings up to date our entire series, which includes follow-up of 15 children over 5 yr, 7 of whom have been followed for more than 10 yr. The two-stage proximally based reversed antiperistaltic gastric tube placed retrosternally is still our procedure of choice, although since our last report in 1973 several other methods (one-stage, transthoracic, subcutaneous) have been used, and the spleen has not been removed in our more recent operations. Whether the esophagogastric tube anastomosis is primary or secondary or is in the chest or neck, leakage is still the most common complication (63%), with all but three closing spontenously. A continuing problem may be an anastomotic stricture (43%) that will require some dilatations. Mild sacculation or tortuosity of the gastric tube has been encountered only once. Despite the above problems, the eventual outcome in the growing child with a gastric tube replacement continues to be a satsifying one. We continue to use the gastric tube operation when replacement of the esophagus is required.

Adolescent↗