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Biomedical subjects

E Y Cheng

Publications and source records attributed to E Y Cheng.

At least 73 records · Page 4Linked to original sources

Use of bladder stimulation in high risk patients.

PURPOSE: We evaluated whether intravesical bladder stimulation therapy is effective in improving bladder compliance in patients with myelomeningocele, neurogenic bladder and high risk urodynamic parameters. MATERIALS AND METHODS: We reviewed the charts of all patients treated with bladder stimulation therapy at our institution since 1984, and identified 7 with pretreatment high risk urodynamic findings (percent expected bladder capacity 60% or less and bladder capacity pressure 50 cm. water or greater). Urodynamic and clinical data were reviewed before and after therapy. RESULTS: Following bladder stimulation in 4 of the 7 patients percent expected bladder capacity substantially increased and bladder capacity pressure decreased to safe levels. Two patients had minimal increases in percent expected bladder capacity but bladder capacity pressure decreased to 50 cm. water or less. Overall percent expected bladder capacity increased from an average pretreatment value of 44% before to 65% after bladder stimulation (p < 0.05). Average bladder capacity pressure improved from 63.9 cm. water before to 32.3 cm. water after treatment (p < 0.05). Also, bladder compliance improved in all 7 patients to the point that bladder augmentation was not performed. CONCLUSIONS: Bladder stimulation is effective in improving bladder compliance in high risk patients and it may be a viable alternative to enterocystoplasty. Further long-term followup will be necessary to establish the longevity of this response.

Adolescent↗

Bladder stimulation therapy improves bladder compliance: results from a multi-institutional trial.

PURPOSE: We examined data from multiple institutions to determine whether intravesical bladder stimulation therapy is effective in improving bladder compliance by increasing bladder capacity and lowering bladder storage pressures. MATERIALS AND METHODS: The charts of 568 patients from 11 institutions were evaluated. Of the 568 patients 335 had adequate and accurate pretreatment and posttreatment urodynamic studies, and were included in this study. A total of 155 patients was from Children's Memorial Hospital, while the remaining 180 were from 10 other institutions. Bladder capacity and bladder capacity pressure were determined for each patient before and after therapy. RESULTS: Overall, 53% of patients had increased bladder capacity of 20% or greater after treatment (average increase 105 cc), which represents a 63% increase from pretreatment values. This increase occurred in an average of 1.9 years. Further analysis of this subset of patients revealed that in 90% intravesical storage pressures were decreased or maintained within a safe range (less than 40 cm. water). Evaluation of patients who did not respond to bladder stimulation with a 20% or greater increase in bladder capacity revealed that they had nearly normal bladder capacity before therapy. When the data on bladder capacity and bladder capacity pressure from Children's Memorial Hospital were compared to results from the 10 other institutions, there were no appreciable differences. CONCLUSIONS: Bladder stimulation is effective in increasing bladder capacity without significantly elevating storage pressure in a majority of patients. We conclude that this technique is safe and effective in improving bladder compliance, and that it is reproducible elsewhere.

Adolescent↗

Frequent incidence of extrapulmonary sites of initial metastasis in patients with liposarcoma.

BACKGROUND: The vast majority of soft tissue sarcomas spread initially to the lungs and then to other sites. The lung has been the most carefully monitored organ system during routine surveillance for a metastasis. Liposarcoma is one of the most common soft tissue sarcomas and has been noted to have extrapulmonary sites of initial metastasis. This study was undertaken to investigate both the frequency and distinguishing features of initial extrapulmonary metastasis in patients with liposarcoma. METHODS: A review of 60 patients with liposarcoma treated at the Massachusetts General Hospital (MGH) from 1971 to 1990 was performed. Survival and regression analyses were used to analyze disease free intervals and prognostic factors. RESULTS: Metastatic disease occurred in 37% of patients and local failure in 17%. Among the subset of patients who underwent primary definitive surgery at the MGH, the incidence of local failure was 3%. An unusually high incidence of extrapulmonary site of first metastasis was found. Isolated extrapulmonary disease was the site of initial metastasis in 59% of patients. In contrast to patients with an initial pulmonary metastasis, patients with an initial extrapulmonary metastasis had a statistically significant (P = 0.001) longer disease free interval from diagnosis to first metastasis. CONCLUSIONS: Liposarcoma, in comparison with other soft tissue sarcomas, has a different pattern of metastatic spread, with a tendency toward extrapulmonary sites. In addition, patients with extrapulmonary metastases have a longer disease free interval compared with patients with pulmonary metastasis.

Adolescent↗

Is the 15-in situ clone protocol necessary to detect amniotic fluid mosaicism?

OBJECTIVE: Our purpose was to evaluate the 15-clone analysis for detecting amniotic fluid mosaicism by the in situ method. STUDY DESIGN: A 10-year review was performed of all amniotic fluid mosaicism cases at two institutions using the in situ method exclusively, with sequential clonal analysis to determine the first and second clone in which the abnormal cell line occurred. RESULTS: Of the 28,497 amniotic fluid samples, 73 met criteria for amniotic fluid mosaicism by in situ method (0.26%). There were 54 cases (0.19%) with potential clinical significance (23 autosome and 31 sex chromosome mosaicism); 49 of the 54 cases (89%) were detected in the first six clones, including 22 of 23 involving autosomes and 27 of 31 involving sex chromosomes. In one of the six cases detected after clone 6 (46,XX/47,XX,+21) the mosaic cell line was present in 20% of the clones analyzed and was followed by a voluntary termination of the pregnancy. In the other five cases amniotic fluid mosaicism was present in < 20% of the clones; these included one case of 46,XX/47,XX+mar (15% amniotic fluid mosaicism, voluntary termination of pregnancy), two cases of 45,X/46,XY (10% to 12% amniotic fluid mosaicism, both normal at birth), and two cases of 45,X/46,XX (8% amniotic fluid mosaicism, lost to follow-up; 12% amniotic fluid mosaicism, voluntary termination of pregnancy). By limiting the analysis to six clones, approximately 20% of analysis time could be saved per case, but one autosomal amniotic fluid mosaicism case per 10,000 samples could potentially be missed. CONCLUSION: Reducing the number of clones analyzed by in situ method could result in increased efficiency, decreased costs, and minimal loss of sensitivity.

Amniotic Fluid↗

Role of prenatal ultrasonography in women with positive screen for Down syndrome on the basis of maternal serum markers.

OBJECTIVE: Our purpose was to evaluate the usefulness of prenatal ultrasonography among women with a positive screen for fetal Down syndrome on the basis of three biochemical markers--maternal serum alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol. STUDY DESIGN: A total of 395 women underwent prenatal ultrasonography at a single institution after being identified as screen positive (midtrimester risk > or = 1:195) on the basis of triple-marker screening between 15 and 18 weeks. Ultrasonographic findings were compared with the biochemical markers and the eventual fetal outcome for these patients. Ultrasonographic abnormalities that were evaluated included structural defects, nuchal thickening or cystic hygroma, echogenic bowel, cerebral ventricular dilatation, pyelectasis, and shortened femur. RESULTS: Among 395 patients, 374 (94.7%) had normal karyotype by genetic amniocentesis (n = 232) or postnatal follow-up (n = 142), 18 (4.5%) proved to have Down syndrome, and three had other karyotypic abnormalities. One or more ultrasonographic abnormalities were found in nine of 18 (50%) with Down syndrome compared to 27 of 377 (7.2%) other fetuses (p < 0.001). Fetuses with abnormal ultrasonography results included three with other chromosome abnormalities and five with nonchromosomal anomalies. An abnormal ultrasonography result increased the risk of Down syndrome by 5.6-fold (25% from 4.5%) and a negative result reduced the risk by 45% (2.5% from 4.5%). The value of ultrasonography is further enhanced when all chromosome abnormalities and nonchromosomal anomalies are considered. CONCLUSION: Abnormal ultrasonographic findings increase the risk for Down syndrome, whereas normal findings are less predictive of normalcy. After correction for inaccurate menstrual dates, genetic amniocentesis should be offered in spite of a normal ultrasonography result among women with positive triple screen.

Adult↗

Antibiotic therapy and the anesthesiologist.

The anesthesiologist is frequently responsible for administering antibiotics in the immediate preoperative and intraoperative periods. Anesthesiologists often are not trained in the administration of antibiotics, which can be associated with both acute and long-term complications including potentiation of neuromuscular blocking agents, allergic reactions, and end-organ toxicity. The indications for perioperative antibiotics, proper method of administration, and occurrence and treatment of major side effects of the more commonly recommended prophylactic antibiotics are discussed.

Anesthesia↗

Chromosome painting analysis of early oogenesis in human trisomy 18.

We have used chromosome 18-specific painting probes to analyze early stages of oogenesis in two human trisomy 18 fetuses. At leptotene, a diffuse, nonlinear chromosomal fluorescence was detected as one (27%), two (42%), or three (31%) signals in 534 cells. The variation in size of these signals implies the possibility of associations between homologs prior to zygotene. At pachytene, about 75% (339/453) of the cells had a trivalent configuration, and almost half of these cells exhibited almost complete triple synapses. Approximately 24% of the pachytene cells demonstrated a bivalent:univalent configuration, and 1% exhibited complete asynapsis. Our data imply that triple synapses may be a regular feature of meiosis involving multivalents.

Abortion, Induced↗

Total hip arthroplasty with cement after renal transplantation. Long-term results.

Fifty patients with osteonecrosis following a renal transplantation were managed with a total of seventy-six total hip arthroplasties with cement between 1972 and 1982 at the University of Minnesota. The minimum duration of follow-up was ten years. With use of Kaplan-Meier survivorship analysis, with revision for any reason as the end point, the over-all rate of survival of the implants in all patients was 91 +/- 7 per cent (mean and two standard errors of the mean, 95 per cent confidence interval) at five years and 78 +/- 11 per cent at ten years. The prostheses in the patients who were more than forty years old had a rate of survival of 87 +/- 18 per cent and 72 +/- 30 per cent at five and ten years, respectively, compared with 92 +/- 7 per cent and 80 +/- 12 per cent for the patients who were less than forty years old. The acetabular components had a 94 +/- 6 per cent rate of survival at five years and an 86 +/- 9 per cent rate at ten years. The femoral components had a 97 +/- 4 per cent rate at five years and an 87 +/- 9 per cent rate at ten years. We concluded that the results of total hip arthroplasty with cement after renal transplantation are satisfactory and are comparable with those for patients of similar age who have not had a renal transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetabulum↗

The cost of sedating and paralyzing the critically ill patient.

The cost of health care is consuming an ever-increasing amount of United State's gross domestic product. It is estimated that 15% of health care dollars are spent in the ICU. Drugs used in the ICU account for approximately 10 to 15% of costs. Many of the sedatives, analgesics, and neuromuscular blocking agents have high acquisition and indirect costs. Educating ICU practitioners on cost issues and key indications for these drugs not only may help with cost containment in the ICU but also can improve patient care.

Adult↗

Early response to pulse oximetry alarms with telemetry.

Twenty ICU patients were monitored for an average of 45 hr each, with both bedside and nursing station monitors, which were set to alarm audibly if the patient's oxygen saturation dropped below 90%. Bedside alarms alerted caregivers to 51 of the 74 hypoxemic events; central alarms alerted personnel to the other 23 events. The alarms led to a change in treatment in 35 of the 48 (73%) true desaturation episodes. We conclude that central oximetric monitoring may help with detection of arterial desaturation events even in a well-staffed ICU.

Adult↗

Topographical differences in the direct effects of isoflurane on airway smooth muscle.

Volatile anesthetics have a direct relaxant effect on airway smooth muscle, but it is not known whether this effect is similar throughout the bronchial tree. We studied the direct relaxation effect of isoflurane on isolated proximal (outer diameter [OD] 4-6 mm) and distal (OD 0.7-1.5 mm) canine airways precontracted with acetylcholine. Proximal and distal airway rings were suspended in tissue baths and stretched to their optimum length. A dose-response curve was obtained for each airway ring with log increments of acetylcholine. Maximum contraction was reached with 10(-2) mol/L of acetylcholine for the proximal airway smooth muscle (7.0 +/- 0.3 g of tension) and 10(-3) mol/L of acetylcholine for the distal airway smooth muscle (2.3 +/- 0.1 g of tension). Based on the dose-response curve, the ED50 of acetylcholine was calculated (1.26 +/- 0.37 x 10(-4) mol/L for proximal airway smooth muscle; 2.12 +/- 1.14 x 10(-5) mol/L for distal airway smooth muscle) and administered to each tissue bath, after which the stabilized response was recorded. A randomly selected dose of isoflurane (1, 2, or 2.6 dog minimum alveolar anesthetic concentration [MAC] was then administered to each bath and the relaxant responses were recorded. The proximal and distal airways relaxed with increased doses of isoflurane in a dose-related manner.

Animals↗

An association between elevated levels of human chorionic gonadotropin in the midtrimester and adverse pregnancy outcome.

OBJECTIVE: Unexplained elevations in maternal serum alpha-fetoprotein in the midtrimester are associated with adverse pregnancy outcome. Recently it has also been suggested that elevations of maternal serum human chorionic gonadotropin in the second trimester may be associated with adverse pregnancy outcome. STUDY DESIGN: We conducted a cohort study of 460 women at Swedish Medical Center, Seattle, Washington, between Jan. 1, 1990, and Aug. 15, 1991, inclusive. Entry criteria for the cohort included (1) triple screen analysis (maternal serum alpha-fetoprotein, human chorionic gonadotropin, unconjugated estriol) between 15 and 18 weeks' gestation, (2) a risk for Down syndrome of more than one in 195 on the basis of triple screen analysis, (3) study group human chorionic gonadotropin > or = 2 multiples of the median and referent group < or = 2 multiples of the median, alpha-fetoprotein < or = 2 multiples of the median, unconjugated estriol > or = 0.5 multiples of the median, and (4) chromosomally normal single gestation without anomalies. Cumulative incidence risk ratios were estimated for each pregnancy outcome as a measure of the relative association with elevated human chorionic gonadotropin (> or = 2.0 multiples of the median) and adverse pregnancy outcome: low birth weight, < or = 2500 gm; preterm delivery, < 37 weeks' gestation; and small for gestational age, < or = 10th percentile. The Mantel extension test was used to evaluate any apparent linear trend in risk between level of human chorionic gonadotropin and adverse pregnancy outcome. RESULTS: Elevated human chorionic gonadotropin levels were associated with an increased risk for low birth weight (relative risk = 4.0), preterm delivery (relative risk = 2.8), and small for gestational age (relative risk = 1.8). The risk for each adverse outcome increased with increasing levels of human chorionic gonadotropin. CONCLUSIONS: Elevations of human chorionic gonadotropin in the midtrimester appear to be associated with adverse pregnancy outcome. The magnitude of the risk correlates with the level of human chorionic gonadotropin. This risk appears to be independent of the risk for adverse pregnancy outcome associated with unexplained elevations of maternal serum alpha-fetoprotein.

Chorionic Gonadotropin↗

Response of the newborn ureteropelvic junction complex to induced and later reversed partial ureteral obstruction in the rabbit model.

The clinical controversy regarding the timing of surgery for asymptomatic newborns with obstructed hydronephrosis was addressed using a model of reversible partial ureteral obstruction in the newborn rabbit. The histomorphometric changes in the ureteropelvic junction complex (for example, pelvis, ureteropelvic junction and upper ureter) and kidney in 44 normal cases were determined and compared with the effects of 47 cases of ongoing partial obstruction and timed reversal of partial obstruction at 1 week in 9 cases, at 2 weeks in 10 or at 4 weeks in 10 (end of the study at age 8 weeks). After partial obstruction hydronephrosis appeared by 1 week postoperatively. There were progressive increases in the thickness of the lamina muscularis and mass index of smooth muscle and collagen (all p < 0.001). However, since the per cent surface area of smooth muscle did not change significantly in comparison to normal, there was disproportionately more collagen. For reversals at 1 week the muscle and collagen in the lamina muscularis were not significantly different from normal. For reversals at 2 weeks the mass index of collagen was greater than normal (p < 0.05) and reversal at 1 week (p < 0.05). For reversals at 4 weeks the lamina muscularis was thicker, and the mass index of collagen and muscle was greater than the earlier reversal groups and normal (all p < 0.05). In conclusion, partial ureteral obstruction causes progressive thickening of the lamina muscularis by collagen and muscle with a disproportionately greater increase in collagen than muscle. The earlier the obstruction can be reversed, the more normal is the ureteropelvic junction complex histology. The functional significance of these changes needs to be determined.

Animals↗