Biomedical subjects

C L Snyder

Publications and source records attributed to C L Snyder.

At least 19 recordsLinked to original sources

PubMed2003

Carrier risk status changes resulting from mutation testing in hereditary non-polyposis colorectal cancer and hereditary breast-ovarian cancer.

CONTEXT: In hereditary cancer syndrome families with an identified cancer associated mutation, mutation testing changes the carrier risk status of the tested person and may change the carrier risk status of relatives. OBJECTIVE: This study aimed to describe the change in the distribution of carrier risk status resulting from testing in hereditary breast-ovarian cancer (HBOC) and hereditary non-polyposis colorectal cancer (HNPCC) families. DESIGN: This was an observational cohort study. PATIENTS: The cohort included members of 75 HBOC and 47 HNPCC families. Of the 10 910 cohort members, 1408 were tested for a mutation and learned their test results. OUTCOME MEASURE: Carrier risk for all cohort members was assessed before and after mutation testing. RESULTS: There was a change in carrier risk status in 2906 subjects after testing of 1408 family members. The most common type of carrier risk change, from at risk to non-carrier status, accounted for 77% of the risk changes; 12% were a change to known carrier status from a lower risk. Sixty percent of persons with a carrier risk status change were not themselves tested; their risk status changed because of a relative's test result. CONCLUSIONS: Carrier risk status changes from uncertainty to certainty (that is, to carrier or to non-carrier) account for 89% of risk changes resulting from testing. These risk changes affect cancer prevention recommendations, most commonly reducing their burden. Current practices do not ensure that untested family members are informed about changes in their carrier risk status which result from mutation testing of their relatives.

Adaptor Proteins, Signal Transducing↗

PubMed2002

Minimally invasive bar repair for 'redo' correction of pectus excavatum.

BACKGROUND/PURPOSE: A small percentage of patients who have undergone traditional, "Ravitch-type" pectus excavatum repair present with unsatisfactory results and require a second procedure for correction. Reoperative open surgery for pectus excavatum has been associated with extensive dissection and substantial blood loss. The minimally invasive (MIS) bar repair for the correction of pectus excavatum has been gaining acceptance. This study evaluates the authors results with patients who have undergone the MIS bar repair for redo correction of their pectus excavatum. METHODS: A retrospective chart review of all patients undergoing MIS bar repair between December 1997 and August 2001 was performed. Information about demographics, deformity, operative course, complications, and early outcome was recorded. RESULTS: Ninety-two patients underwent MIS repair during this period. Ten patients had redo MIS bar repair for unsatisfactory prior open correction. Operating time was 52 minutes for standard patients and 70 minutes for the redo patients (P <.001). Blood loss and postoperative hospitalization were similar between groups. CONCLUSION: The minimally invasive pectus repair can be performed safely with minimal blood loss and short operating time in patients who have undergone prior unsatisfactory open repair of pectus excavatum and can be an alternative approach to reoperative open repair in these patients.

Child↗

PubMed2001

Vascular anomalies and tracheoesophageal compression: a single institution's 25-year experience.

BACKGROUND: Vascular rings are uncommon anomalies in which preferred strategies for diagnosis and treatment may vary among institutions. In this report, we offer a description of our approach and a review of our 25-year experience. METHODS: A retrospective review was conducted of all pediatric patients with symptomatic tracheoesophageal compression secondary to anomalies of the aortic arch and great vessels diagnosed from 1974 to 2000. RESULTS: Thirty-one patients (38%) of eighty-two patients (mean age, 1.7 years), were identified with double aortic arch, 22 patients (27%) with right arch left ligamentum, and 20 patients (24%) with innominate artery compression. Our diagnostic approach emphasized barium esophagram, along with echocardiography. This regimen was found to be reliable for all cases except those with innominate artery compression for which bronchoscopy was preferred, and except those with pulmonary artery sling for which computed tomography or magnetic resonance imaging, in addition to bronchoscopy, were preferred. Left thoracotomy was the most common operative approach (70 of 82; 85%). Ten patients (12%) had associated heart anomalies, and 6 (7%) patients underwent repair. Complications occurred in 9 (11%) patients and led to death in 3 (4%) patients. CONCLUSIONS: In our practice, barium swallow and echocardiography are sufficient in diagnosing and planning the operative strategy in the majority of cases, with notable exceptions. Definitive intraoperative delineation of arch anatomy minimizes the risk of misdiagnosis or inadequate treatment.

Aorta, Thoracic↗

PubMed2001

Management of intestinal atresia in patients with gastroschisis.

BACKGROUND/PURPOSE: Intestinal atresia occurs in approximately 10% to 20% of children with gastroschisis and may be missed at the initial closure if a thick peel obscures the bowel. Some investigators have identified intestinal atresia as a significant contributor to morbidity and mortality. The authors reviewed their experience with gastroschisis and intestinal atresia in an attempt to answer the following questions. What is the incidence of this association? How often is the intestinal atresia unrecognized as a result of the peel? What is the optimal management for infants with atresia and gastroschisis, and does the atresia affect morbidity or mortality? METHODS: The hospital charts and medical records of all patients with gastroschisis treated at our institution from 1969 to present were reviewed thoroughly. Parameters analyzed included gestational age (GA), birth weight (BW), antenatal diagnosis, mode of delivery, type of closure, era of repair, presence of other major anomalies, and development of necrotizing enterocolitis. Morbidity and mortality rates were examined. Characteristics of patients with and without atresia were compared. Chi-squared was used for crosstabular analysis. Sample parameters were compared with Student's t test. P values of less than.05 were considered significant. RESULTS: A total of 199 babies had gastroschisis and 25 (12.6%) had intestinal atresia. Intestinal atresia was initially unrecognized in 3 patients. Most patients (80%) underwent primary closure of the abdominal wall. Initial stoma formation and delayed anastomosis was performed in 12 (48%) patients, none of whom required prosthetic material for abdominal wall closure. Initial stomas were avoided in 5 patients who required SILASTIC (Dow Corning, Midland, MI) silos. Skin closure alone was used in 2 babies. The level of the atresia was most commonly jejunoileal (20 of 25, 80%). Mean hospital stay was increased in babies with intestinal atresia, 36.2 versus 63.1 days (P <.001). CONCLUSIONS: Although patients with intestinal atresia did have feeding delays, an increased incidence of adhesive intestinal obstruction, and prolonged hospitalization, neither chi(2) nor logistic regression analysis showed any correlation with mortality. Intestinal repair at the first operation is sometimes possible and depends on the severity of the peel. Delayed repair of the atresia after a period of bowel decompression and parenteral nutrition is preferred, but in certain situations (colonic atresia, necrotic intestine, complicated atresia) may not be possible. The combination of stomas and prosthetic material can be avoided in almost all patients. A management algorithm for patients with atresia and gastroschisis is discussed.

Female↗

PubMed2001

Semiquantitative polymerase chain reaction in RNase-producing tissues: Analysis of the developing pancreas.

BACKGROUND/PURPOSE: Many studies in pediatric surgical research use a quantitative analysis of gene expression in microscopic quantities of tissue. The authors describe an analysis of the beta-tubulin mRNA content of the embryonic pancreas, which contains abundant endogenous RNases. A detailed analysis of this RNase-containing system will provide a good template for analysis of other potentially simpler systems. METHODS: Embryonic mouse pancreases were harvested at serial gestational ages. DAPI nuclear staining allowed for counting of cells. cDNA was amplified using a fluoresceinated primer and the normalized fluorescence determined. Known numbers of molecules were amplified in parallel as a standard control. RESULTS: The number of cells increased from 38,000 to 2,700,000 between embryonic day 10.5 (E10.5) and E18.5. mRNA for beta-tubulin did not increase proportionately. Assuming a yield of 100% at E10.5 when no RNases are present, the yield of expected mRNA was 65.3% at E12.5, 13.8% at E15.5, and 0.9% at E18.5, presumably because of the appearance of RNases. CONCLUSIONS: Several parameters must be considered in performing semiquantitative reverse transcription polymerase chain reaction: (1) the yield of RNA based on the projected amount of mRNA, (2) the number of cells in the tissue, and (3) a known number of template molecules amplified in parallel.

Animals↗

PubMed2001

Minimally invasive repair of pectus excavatum: a single institution's experience.

BACKGROUND: The Nuss repair of pectus excavatum is a relatively new, minimally invasive surgical (MIS) alternative to the traditional open "Ravitch-type" operation. We have one of the larger single-center experiences to date, and we conducted this clinical study to evaluate our early experience, emphasizing initial outcome and technical modifications designed to minimize complications. METHODS: A retrospective chart review was performed on 112 patients who underwent 116 pectus excavatum repairs between January 1995 and January 2001. The Nuss procedure was performed in 80 patients, and open repair was performed in 32 patients. Information about demographics, deformity, operative course, complications, and early outcome was recorded. RESULTS: Operative duration was 143 minutes for the open group and 53 minutes for the Nuss MIS group (P <.001). Blood loss was 6 mL/kg for the open group and 0.5 mL/kg for the MIS group (P <.001). Postoperative hospitalization was 3.2 days for the open group versus 3.7 days for the MIS group (P<.05). CONCLUSIONS: The MIS pectus repair can be performed safely with minimal blood loss and reduced operative time. Short-term analysis of the quality of repair, including absence of preoperative symptoms, patient satisfaction, and cosmetic appearance are encouraging.

Adolescent↗

PubMed2001

Effect of pediatric surgical practice on the treatment of children with appendicitis.

OBJECTIVE: Acute appendicitis in children is managed by both general surgeons (GSs) and pediatric surgeons (PSs). Our objective was to investigate the economics of surgical care provided by either GSs or PSs for appendicitis. METHODS: The outcome of children within our state who underwent operative treatment for appendicitis (January 1994 to June 1997) by board-certified GSs were compared with the results of PSs. Data were sorted according to patient age and diagnosis according to the International Classification of Diseases, Ninth Revision. Analysis of variance was performed on continuous data, and chi(2) analysis was performed on nominal data; data are depicted as mean +/- standard error of the mean. RESULTS: GSs (n = 2178) managed older children when compared with PSs (n = 1018; 11.0 +/- 0.1 vs 9.1 +/- 0.1 years) and less frequently treated perforated appendicitis (18.8% vs 31.9%). Independent of diagnosis (simple or perforated appendicitis), younger children (0-4 years, 5-8 years, and 9-12 years) who were treated by PSs had a significantly shorter hospital stay and/or decreased hospital charge when compared with those who were treated by GSs. However, older children (13-15 years) seemed to have comparable outcomes. CONCLUSIONS: Younger children with appendicitis have reduced hospital days and charges when they are treated by PSs.

Adolescent↗

PubMed2000

Multiple gastrointestinal atresias with cystic dilatation of the biliary duct.

A term newborn developed signs and symptoms of an upper-intestinal obstruction. A palpable transverse upper-abdominal mass was identified. An ultrasound examination demonstrated a cystic mass with massive dilatation of the biliary tree. At laparotomy, dozens of segmental intestinal atresias (IA) from the jejunum to the rectum were identified. The cystic mass was the duodenum, obstructed distally from the atresias and proximally from an antral web. The biliary dilatation was due to normal drainage into a closed-loop duodenal obstruction, and was relieved by division of the web. The multiple atresias were explored, but establishment of intestinal continuity was impossible. The entity of multiple segmental IAs in association with cystic biliary dilation has been previously described, but there are no recorded survivors; 35 patients have been reported in the world literature. Our patient was the longest survivor; she finally died after 2 years of gastrostomy-tube drainage and total parenteral nutrition while awaiting intestinal transplantation. Only 5 patients other than ours had documented immune-system abnormalities. We review the findings and management of this rare syndrome.

Bile Duct Diseases↗

PubMed2000

Nonoperative management of newborn splenic injury: a case report.

Traumatic injury of the spleen is rare in newborns. Nonoperative management of pediatric splenic injuries is now recognized as the treatment of choice, but there is scant experience with the problem in neonates. The authors report their experience with a neonatal splenic rupture, managed nonoperatively.

Birth Injuries↗

PubMed1999

Outcome analysis for gastroschisis.

BACKGROUND/PURPOSE: Several factors are reportedly associated with an adverse outcome in gastroschisis, including mode of delivery, in utero diagnosis, type of closure, concurrent anomalies, intestinal atresia, and necrotizing enterocolitis (NEC). Since 1969, the authors have treated 185 patients who had gastroschisis. The authors analyzed their database to identify variables associated with increased morbidity and mortality. METHODS: A retrospective study of all patients with gastroschisis treated at our institution in the last 30 years was performed. The characteristics of survivors and nonsurvivors were compared. A logistic regression analysis was performed, with survival as the dependent variable, and the following parameters as independent variables: in utero diagnosis, mode of delivery, gestational age and birth weight, era of repair, type of closure, presence of other associated anomalies, intestinal atresia, and development of necrotizing enterocolitis. Further logistic regression analysis was performed, with various indicators of morbidity as dependent variables. These included development of sepsis, bowel obstruction, and complications related to the closure or to the silo. No attempt at long-term follow-up was made. RESULTS: A total of 185 infants with gastroschisis were treated at our institution from 1969 to 1999. Mean gestational age was 36.6 weeks, and the mean birth weight was 2,501 g. A total of 21 infants had intestinal atresia. NEC developed in 8 infants. Six infants had other serious anomalies. The overall survival rate was 91%. Survival improved in last 2 decades (94%). There were no differences in gestational age, birth weight and mode of delivery, method of closure, or presence of intestinal atresia between survivors and nonsurvivors. Only the era of repair (P = .002), presence of necrotizing enterocolitis (P = .044), and presence of other major anomalies (P < .001) correlated with mortality in the logistic regression analysis. Sepsis, bowel obstruction, and closure complications accounted for most of the morbidity. Analysis of these three morbidity factors identified low gestational age (P = .038) and development of necrotizing enterocolitis (P = .020) as independent predictors of sepsis. Closure complications were only associated with lower birth weight (P = .006). No predictors of bowel obstruction were identified. CONCLUSIONS: Mode of delivery, method of closure, birth weight and gestational age, and the presence of intestinal atresia do not appear to correlate with survival in infants with gastroschisis. Only the presence of another major anomaly, the era of repair, and the development of necrotizing enterocolitis were associated with increased mortality. Degree of prematurity and development of enterocolitis were associated with an increased incidence of septic complications. Low birth weight was a marker for closure complications. Type of delivery (vaginal or cesarean section) had no influence on either morbidity or mortality.

Birth Weight↗

PubMed1999

Survival of patients with esophageal atresia: influence of birth weight, cardiac anomaly, and late respiratory complications.

PURPOSE: The aim of this study was to determine the influence of various prognostic factors on the outcome of esophageal atresia patients. METHODS: The authors reviewed 240 charts of patients admitted with esophageal atresia or tracheoesophageal fistula (EA-TEF) in a single institution. A logistic regression model was used with survival as the dependent variable and era of repair, birth weight, and cardiac anomaly as independent variables. RESULTS: Era was statistically significant (P = .011); 87% (117 of 134) of patients survived in the era from 1980 through 1997 compared with 78% (83 of 106) from 1960 through 1979. Cardiac anomaly (CHD) was a significant risk factor (P = .001); 88% (176 of 199) survived without cardiac anomaly, whereas only 59% (24 of 41) survived with cardiac disease. Eighty-four percent (185 of 219) of infants with a birth weight (BW) of more than 1,500 g survived, compared with 71% (15 of 21) of infants with a birth weight of less than 1,500 g. This was not statistically significant (P = .59). Early hospital deaths were primarily cardiac and chromosomal (61%). Late deaths were primarily respiratory (59%; two-tailed Fisher's Exact test, P = .004). CONCLUSIONS: (1) Survival of patients with esophageal atresia has significantly improved in the recent years. (2) Low birth weight (<1,500 g) does not seem to affect survival. (3) Associated cardiac and chromosomal anomalies are significant causes of death, particularly for early demise. (4) Late death from respiratory disease (tracheomalacia, reactive airway disease, reflux, and aspiration) warrants attention, and a close follow-up of postoperative patients is suggested.

Abnormalities, Multiple↗

PubMed1998

Inferior vena caval obstruction from a horseshoe kidney: report of a case with operative decompression.

Horseshoe kidney is a common anomaly with frequent associated anomalies. The confluence of the lower poles of the kidneys lies anterior to the inferior vena cava. The authors were unable to find any reports in the world's literature of a vena caval obstruction caused by the presence of a horseshoe kidney. The authors report such a case presenting as bilateral lower leg swelling.

Cellulitis↗

PubMed1998

Comparison of muscle-sparing thoracotomy and thoracoscopic ligation for the treatment of patent ductus arteriosus.

PURPOSE: We reviewed our experience with the treatment of patent ductus arteriosus (PDA), and compared two therapeutic techniques; muscle-sparing thoracotomy (MST) and thoracoscopic PDA ligation (TPDAL). METHODS: We reviewed the clinical records and operative reports of 19 nonnewborn patients who were treated at our institution for PDA. Eleven patients underwent TPDAL and eight patients MST. The TPDAL patients underwent thoracoscopic clipping (ligation) of the PDA, whereas the MST group had a complete division of the ductus. A two-tailed Student's t test was used to calculate the 95% confidence intervals for length of operation, number of doses of intravenous narcotics and hospital stay. Costs were also compared. RESULTS: All patients underwent diagnostic echocardiography in the evaluation of an asymptomatic murmur. Both groups were similar in age (average, 4 years) and gender. All procedures were performed electively. Two thoracoscopic attempts were aborted, one for bleeding and the other for inadequate clip size. The length of the procedure averaged 1.3 hours +/- 0.330 SD for TPDAL versus 1.4 hours +/- 0.335 SD for MST. Five of the nine successful TPDAL patients were admitted to the Pediatric Intensive Care Unit (PICU) with an average length of stay of 20 hours, and two of eight MST patients stayed in the PICU for average of 18 hours. All patients were extubated after the procedure. Chest tubes were placed in two TPDAL patients and three MST patients. However, two patients who underwent TPDAL required tube thoracostomy for persistent postoperative pneumothorax. Average number of intravenous narcotics administered for the TPDAL was 1.2 doses per patient and for MST, 1.75 doses per patient. Mean hospital stay for TPDAL was 1.33 +/- 0.71 SD days and for MST 1.8 +/- 0.83 SD days. Ninety-five percent (95%) confidence intervals for the difference in means demonstrated no difference between the two groups for length of operation, hospital stay, or number of doses of intravenous narcotics administered. CONCLUSIONS: The authors were unable to identify any benefit to thoracoscopic patent ductus arteriosus ligation versus muscle-sparing thoracotomy in terms of hospital stay, length of operation, or morbidity. Additionally, with MST there is a complete division of the PDA theoretically decreasing the risk of recurrence in comparison with clip ligation.

Case-Control Studies↗

PubMed1998

Balloon extraction of esophageal foreign bodies in children.

BACKGROUND: Whereas esophageal foreign bodies are commonly removed with rigid esophagoscopy under general anesthesia, selected foreign bodies also can be removed using a Foley catheter balloon under fluoroscopic control without anesthesia. The authors prefer to initially attempt removal of smooth, radiopaque esophageal foreign bodies using the balloon technique and then proceed to rigid esophagoscopy if unsuccessful. METHODS: The authors reviewed their 7-year experience with this approach in 276 children with esophageal foreign bodies. RESULTS: One hundred seventy-three children underwent attempted balloon extraction, and 146 of these underwent successful removal with this method. Fifteen remained lodged in the esophagus and were subsequently removed by esophagoscopy, and 12 passed into the stomach and were observed. The only complication was one episode of epistaxis that resolved. Success of the balloon method was not related to patient age, foreign body duration, location, or presenting symptoms. The use of more than 5 minutes of fluoroscopy time was associated with a low likelihood of successful extraction. CONCLUSION: The balloon extraction technique is a safe and effective alternative to rigid esophagoscopy for the removal of selected esophageal foreign bodies in children.

Catheterization↗

PubMed1998

Glans approximation procedure urethroplasty for the wide, deep meatus.

OBJECTIVES: To assess the reliability, cosmesis, and complication rate of the glans approximation procedure (GAP). METHODS: We reviewed 37 consecutive GAP urethroplasties performed at the Children's Mercy Hospital in Kansas City, Missouri over a 5-year period, performed by three different pediatric surgeons. All patients selected had a large, deep ventral groove, typically with a wide open urethral meatus. RESULTS: The mean age was 18 months, with a mean follow-up of 28 months. Of the 37, there was one urethrocutaneous fistula that has since been easily repaired with good results. The parents have been very pleased with the results in all cases, with a straight and strong urinary stream. There was one episode of transient erythema, possibly representing an infection, which resolved after 3 days of oral antibiotics. CONCLUSIONS: The GAP is technically easy, reliable, and offers a relatively low complication rate for the repair of a very select group of patients with hypospadias with a deep ventral glanular groove and wide-mouthed meatus.

Follow-Up Studies↗

PubMed1997

The 're-do' chest wall deformity correction.

BACKGROUND: A small percentage of patients who undergo surgical correction of a chest wall deformity will have results so unsatisfactory that a second procedure, the so-called "re-do," will be required. CONCLUSIONS: The literature contains very little information regarding the technique and results of these procedures. Based on experience with 18 "re-do" procedures, the authors believe that recurrent deformities should be surgically corrected. Although this is a somewhat diverse group based on age at the first and second procedure, type of original operative procedure, and interval between the procedures, the operative approach is standard, and the results are predictable.

Adolescent↗

PubMed1997

Efficacy of partial wrap fundoplication for gastroesophageal reflux after repair of esophageal atresia.

Gastroesophageal reflux (GER) often develops in children who have undergone prior repair of esophageal atresia/tracheoesophageal fistula (EA/TEF). Fundoplication is necessary in many of these children. The complete wrap (Nissen) fundoplication is often used in this setting. However, poor results have been noted, with a mean failure rate of 30% reported in four recent studies. A partial wrap fundoplication for GER associated with EA/TEF is theoretically attractive, because the poor esophageal motility and diminished acid clearance (already physiologically present) is exacerbated by a complete wrap fundoplication. The authors reviewed their extensive experience with partial wrap (Thal) fundoplication in EA/TEF to determine if the failure rate was better than that reported for the Nissen fundoplication. In the past 18 years, the authors performed 1,467 fundoplication procedures. During the same period, 143 children underwent repair of EA/TEF. Fifty-nine children underwent fundoplication after a previous EA/TEF repair. Most of the fundoplications (58 of 59, 98%) were Thal procedures. Defining failure strictly as a need for reoperation, the failure rate in our series was 15% (9 of 59 children). Compared with the failure rate in the 1,408 non-EA/TEF patients (61 of 1408, 4.3%), results were significantly worse for the EA/TEF group (P > .001). The failure rate of Thal fundoplication performed for GER in the EA/TEF population is substantially higher than the non-EA/TEF patients. The same factors responsible for the development of reflux in these children (poor acid clearance, altered motility, esophageal shortening) may contribute to the higher failure rate. Although partial wrap fundoplication frequently failed (15%), the results were still substantially better than those reported for Nissen fundoplication in these children (30% failure rate).

Adolescent↗

PubMed1997

Survival after necrotizing enterocolitis in infants weighing less than 1,000 g: 25 years' experience at a single institution.

Necrotizing enterocolitis (NEC) primarily affects premature newborns. Regional and national decreases in the mean birthweight and gestational age of neonatal intensive care unit (NICU) admissions prompted a review of NEC in VLBW (very low birth weight, defined as < 1,000 g) infants in our institution over a 25-year period. There were 266 patients treated for NEC during the study interval. We compared 71 VLBW with 195 non-VLBW infants and found that VLBW infants were: fed later (6.4 days v 4.1 days, P = .009), developed NEC later (20.8 days v 13.1 days, P = .002), had significantly lower 1- and 5-minute Apgar scores, were more likely to require surgery (51% v 34%, P = .016), more often had panintestinal (defined as > 75% of intestinal length) involvement (10% v 4%, P = .043), and had poorer survival (56% v 72%, P = .013). Overall survival after NEC has improved over the study interval, both in our series and in other reports. However, the increasing number of VLBW infants who have NEC represent a subgroup who appear to be generally more ill, develop NEC later, require surgery with greater frequency than their non-VLBW counterparts, and are less likely to survive.

Age of Onset↗