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Ruey-Kang R Chang

Publications and source records attributed to Ruey-Kang R Chang.

15 recordsLinked to original sources
PubMed2006

Risk factors for deaths occurring within 30 days and 1 year after hospital discharge for cardiac surgery among pediatric patients.

BACKGROUND: Little is known regarding the risk factors for early and late death after hospital discharge among pediatric patients undergoing cardiac surgery. METHODS: Statewide hospital discharge data from California in 1989 to 1999 were used to study outcomes of children <18 years old who had a procedure code (by International Classification of Diseases, Ninth Revision, Clinical Modification) indicating cardiac surgery. The outcome variable was death occurring after hospital discharge. Postdischarge deaths were identified by linking hospital discharge data to statewide death registry data. Cardiac surgical procedures were grouped into 23 categories to adjust for risk involved with the procedures. We used logistic regression to evaluate risk factors for postdischarge mortality, including variables age, sex, race and ethnicity, type of insurance, home income, date and month of surgery, type of admission, hospitals case volume, and the various types of procedures. RESULTS: There were 25,402 cardiac surgery cases with 1505 inhospital deaths. Of 23,897 hospital discharges, 148 deaths (0.62%) occurred within 365 days after discharge, including 37 deaths within 30 days; 44 deaths at 31 to 90 days; and 67 deaths at 91 to 365 days. Logistic regression showed young age was an important risk factor for postdischarge death with an odds ratio of 4.8 for neonates and 3.5 for infants, compared with children >1 year old. Another significant risk factor was the type of procedure. For death <30 days after discharge, Norwood operation (odds ratio 8.4 compared with closure of ventricular septal defect) was a risk factor. For death that occurred between 31 and 365 days, significant risk factors were truncus arteriosus repair, total anomalous pulmonary vein repair, aortopulmonary shunt, and open valvotomy. Sex, race/ethnicity, home income, and hospital case volume were not significant predictors of postdischarge deaths. CONCLUSIONS: Many demographic and socioeconomic variables affecting inhospital death were not significant predictors for postdischarge death. Important risk factors for postdischarge death were young age and the type of surgery performed.

Adolescent↗
PubMed2005

Changes in the newborn delivery practice and neonatal outcomes as financing changed in Los Angeles County and Orange County, California.

The objective of this investigation was to study changes in newborn delivery during a period of extensive changes in financing mechanisms in Los Angeles County (LAC) and Orange County (OC), California. California hospital discharge data (1990-1999) were used for the analyses. The Herfindahl-Hirschman Index (HHI) was calculated to measure the distribution of newborn deliveries among hospitals. Birth outcomes, including cesarean section rates, in-hospital deaths, interhospital transfers, and selected neonatal morbidities, were assessed. A total of 2,351,209 newborn deliveries in 124 hospitals were recorded. The number of newborn babies delivered per year decreased by 21% during the study period. A dramatic decline in the number of deliveries (up to 80%) was seen in all four LAC county hospitals. The cesarean section rate increased for Medi-Cal patients during the study period, compared with no change in the rate for privately insured patients. The newborn interhospital transfer rate for patients in LAC remained unchanged. The newborn in-hospital mortality rates for both LAC and OC decreased during the study period.

California↗
PubMed2004

B-type natriuretic peptide in children after cardiac transplantation.

BACKGROUND: The normal B-type natriuretic peptide (BNP) concentration and the significance of increased BNP concentration in children after orthotopic heart transplant (OHT) remain unknown. We sought to determine plasma BNP concentrations in relation to post-transplant time and to explore factors associated with increased BNP in pediatric OHT recipients. METHODS: We obtained plasma BNP concentrations in 44 pediatric patients at 1 to 171 months after OHT. All patients underwent endomyocardial biopsies and echocardiography. We analyzed the association between BNP and post-transplant time, as well as the association between BNP concentration and left ventricular end-diastolic dimension (LVEDD) after transplantation. RESULTS: The age of study patients ranged from 0.9 to 21.2 years (mean, 11.4 +/- 6.2 years; median, 10.5 years). We evaluated BNP concentrations immediately after transplantation. The mean BNP concentration decreased exponentially to 100 pg/ml by 14 weeks after OHT. Although BNP concentration relative to time after OHT varied among individuals, all patients with multiple measurements showed predictable rates of decrease. This decrease in BNP concentration was not associated with changes in LVEDD. CONCLUSIONS: Plasma BNP concentration was elevated in children after OHT and decreased exponentially in time to 100 pg/ml by 14 weeks after OHT. The decrease in BNP concentration was unrelated to left ventricular dimension.

Adolescent↗
PubMed2004

Echocardiographic assessment of the right ventricular stress-velocity relationship under normal and chronic overload conditions.

UNLABELLED: The effects of chronic volume or pressure overload on the velocity of right ventricular ejection have not been previously well defined. We hypothesized that, as formerly shown for the left ventricle, there would be a direct relationship between the velocity of ejection and an estimate of systolic wall stress. METHODS: Echocardiograms of asymptomatic patients, not on cardiac medications, with either an isolated secundum atrial septal defect > or = 5 mm in diameter or isolated pulmonic stenosis with a peak instantaneous pressure gradient > or = 20 mmHg, were reviewed. Forty-one patients with an atrial septal defect and 34 with pulmonary stenosis met criteria, and were compared to age-matched normal controls. Total subjects were 127 with ages ranging from 1 day to 54 years. Right ventricular monoplane ejection fraction, ejection time corrected for heart rate (ETc), mean normalized systolic ejection rate (MNSERc) and meridianal peak-systolic wall stress (WSps) were measured. RESULTS: Compared to controls, ejection fractions were not significantly different, but WSps averaged 81% and 110% higher, ETc 8% and 9% longer, and MNSERc 5% and 9% slower in the atrial septal defect and pulmonary stenosis groups, respectively. Among all subjects WSps had a significant linear correlation with ETc (r = 0.61, P < 0.01), MNSERc (r =-0.46, P < 0.01), and ejection fraction (r =-0.19, P < 0.05). CONCLUSIONS: Increases in WSps cause an incremental slowing of MNSERc in the right ventricle, with a relationship that is linear over a wide range of normal and abnormal loading conditions.

Adolescent↗
PubMed2004

Parental preference regarding hospitals for children undergoing surgery: a trade-off between travel distance and potential outcome improvement.

OBJECTIVE: To explore parental preference in the choice between a local and a referral hospital for children undergoing heart surgery. METHODS: One hundred three parents or adult primary caregivers of children referred to a pediatric cardiology clinic were interviewed. Participants were presented with hypothetical scenarios in which they or their children had a heart condition requiring elective surgery. The surgery could be performed at either a local hospital or a regional referral hospital. The travel time to the referral hospital was initially presented as 2 h, and the mortality rate was set at 3% for both the local and the referral hospitals. The parents were then presented with scenarios that sequentially increased the mortality of the local hospital and the distance to the referral hospital, and were asked to choose between the local and regional referral hospitals. RESULTS: When the regional referral hospital was 2 h away and the mortality rates for the referral hospital and the local hospital were equal at 3%, 82.5% of participants chose the local hospital for their children. The percentage of participants choosing the local hospital decreased progressively as the mortality rate of the local hospital increased (to 9.7% at 18% mortality). Between 5% and 10% more participants chose the local hospital when the distance to the referral hospital was increased from 2 h to 4 h. There was no difference in age, sex, ethnicity, language, type of insurance, level of education and availability of personal transportation between participants who chose the regional referral hospital and those who chose the local hospital. Participants who lived closer to the hospital at which the survey was conducted were more likely to choose the local hospital. CONCLUSION: The present study defines a relation between potential outcome improvement and increasing travel distance from a patient or parent's perspective. This trade-off is an important consideration when planning for regionalization.

Adolescent↗
PubMed2003

Parental preference for one-stage versus two-stage surgical repair for children with congenital heart disease.

BACKGROUND: Little is known regarding parental preference for a one-stage complete repair versus a two-staged approach with initial palliation, followed by repair, of the congenital cardiac malformation. METHODS: We interviewed 103 parents of healthy children referred to a clinic for pediatric cardiology. Participants were presented with a hypothetical scenario in which their children had a cardiac lesion requiring surgery. The surgery could be performed either by means of one-stage complete repair, or using a two-stage approach, with palliation first followed by complete repair a year later. The mortality rate for the one-stage repair was set at 5%. Participants were asked to choose between the one- and two-stage approaches, with differing mortality rates for the two-stage approach. The scenarios included options when the two-stage combined mortality rate was lower than the one-stage mortality, and the first stage mortality rate was at 1% and 3%, and when the two-stage combined mortality rate was the same as that for one-stage mortality, these being set at 1% and 3%. RESULTS: When the two-stage combined mortality rate was lower than that of the one-stage repair, participants were more likely to choose the two-stage approach if the first stage mortality rate was 1% as compared to 3% (57% and 44%, respectively, p = 0.04). When the two-stage combined mortality rate was the same as the one-stage approach, participants choosing the two-stage approach when the mortality rate was set at 1%, and when it was raised to 3%, were not significantly different (42% and 34%, respectively, p = 0.24). When the combined two-stage mortality was the same as that set for one-stage repair, participants with no insurance were less likely to choose the two-stage approach than those covered by insurance (p = 0.03). CONCLUSIONS: In the chosen scenarios, when the mortality for a two-stage combined approach is the same as that for one-staged repair, more parents choose the one-staged repair. If the two-stage combined mortality is lower than that for one-staged repair, parents are more likely to choose the two-stage repair if the mortality for the first stage is lower. When the mortality rates for the one-stage and two-stage approaches are the same, people without insurance are more likely to choose one-staged repair.

Adult↗
PubMed2003

Resources, use, and regionalization of pediatric cardiac services.

Care for children with congenital heart disease requires specialized services and various healthcare resources. The purpose of this article is to provide an updated overview of healthcare resources for infants and children with heart disease. In 2001, there were 1609 certified pediatric cardiologists in the United States. The ratio was approximately 45,000 children younger than 18 years per pediatric cardiologist. It is estimated that more than 19,000 cardiac surgeries are performed in children younger than 18 years in the United States each year. This article also reviews the effect of patient characteristics on access to healthcare and use of pediatric cardiac services, and discusses issues related to optimal use of these resources and the development of an organized approach toward service management by regionalization. The authors believe that improved access to high-quality facilities and providers coupled with thoughtful changes in the healthcare delivery system represent an excellent opportunity for optimizing outcomes for children with heart disease.

Cardiac Surgical Procedures↗
PubMed2002

Female sex as a risk factor for in-hospital mortality among children undergoing cardiac surgery.

BACKGROUND: The purpose of this study was to investigate whether sex disparity in cardiovascular outcomes exists in children who undergo cardiac surgery. METHODS AND RESULTS: Statewide hospital discharge data from California from 1995 to 1997 were used. Children <21 years old who had a procedure code (by ICD9-CM) that indicated cardiac surgery were selected. The outcome variable was binary, in-hospital death versus alive at discharge. Twenty-three surgical procedures were selected and adjusted for risk by procedure type. We used logistic regression analysis to evaluate the effect of sex on in-hospital mortality, controlling for age, race and ethnicity, type of insurance, home income, type of admission, date and month of surgery, hospital case volume, and type of procedure. There were 6593 cases of cardiac surgery, with 345 in-hospital deaths (mortality rate 5.23%). Crude mortality rates for males (4.98%) and females (5.54%) were not significantly different. However, fewer females were neonates, and females had more low-risk procedures than males. Multivariate logistic regression showed that females had a higher odds ratio (OR) for mortality than males (OR 1.51, P<0.01). The OR for mortality was 3.86 for neonates and 2.98 for infants compared with children aged > or =1 year. Low-volume hospitals had higher mortality rates than high-volume hospitals (OR 1.67, P<0.01). The risk-adjusted length of hospital stay and charges were similar between females and males. CONCLUSIONS: For children undergoing cardiac surgery, female sex was associated with 51% higher odds of death than male sex. The mechanism by which female sex acts as a risk factor requires further investigation.

Adolescent↗
PubMed2002

Epidemiologic characteristics of children hospitalized for Kawasaki disease in California.

OBJECTIVE: To evaluate the epidemiologic pattern of Kawasaki disease (KD) in California. METHODS: Statewide hospital discharge data from California from 1995 through 1999 were used. Children 0 through 17 years old who had a discharge diagnosis of KD (by ICD9-CM code 446.1) were identified. Precipitation and temperature data of climate divisions of the state were used to determine their possible association with incidences of KD. Multiple regression analysis was performed to evaluate factors related to the KD incidence of the counties. RESULTS: There were 2,325 patients admitted to 194 California hospitals during the 5-year study period. The male-to-female ratio was 1.62. Median age was 30 months; peak incidence by year of age was in the second year of life. Overall annual incidence was 15.3 cases per 100,000 children <5 years old and 3.2 cases per 100,000 children 5 through 9 years old. Compared with 1995 and 1996, the incidence for children <5 years old increased by 30% in 1997 and 1998 (P < 0.01). In contrast the incidence for children 5 through 9 years old remained relatively unchanged. Asians had the highest incidence of 35.3 cases per 100,000 children <5 years old, followed by blacks (24.6) and whites (14.7) (P < 0.01). The number of cases peaked in March and had its nadir in September. In a multiple regression analysis, no association was found between KD incidence and temperature or precipitation. KD incidence was not related to average family size, proportion of Asians in the population, population density or whether the county is in northern or southern California. There was no in hospital death. The median length of hospital stay was 2 days. CONCLUSIONS: The incidence of Kawasaki disease in patients <5 years old increased in 1997 and 1998. Asians had the highest KD incidence compared with other races. Peak incidence was in March, and the lowest incidence was in September. KD incidence was not associated with temperature, precipitation, family size or population density.

Adolescent↗
PubMed2002

Can regionalization decrease the number of deaths for children who undergo cardiac surgery? A theoretical analysis.

OBJECTIVE: The association between high case volumes and better patient outcomes has been demonstrated for many surgical procedures and medical treatments, including surgery for children with congenital heart disease. To simulate the effects of regionalization of pediatric cardiac surgery, we assessed the impact of reducing the number of pediatric cardiac centers on surgical mortality and patient's travel distance. METHODS: This study used abstracted statewide hospital discharge data from California from 1995 to 1997. Case volume and in-hospital mortality for pediatric cardiac surgeries at each hospital were calculated. All hospitals that performed > or =10 pediatric cardiac surgeries in 1995 to 1997 were included in the analysis. To simulate regionalization, we "closed" the hospital with the lowest case volume and redistributed patients from this hospital to the nearest remaining hospitals. The number of in-hospital deaths was then recalculated using the original mortality rate of each remaining hospital multiplied by its new case volume. A multivariate logistic regression was conducted to determine the odds ratios of mortality of various types of surgery compared with closure of ventricular septal defect. This result was used for adjusting for the case-mix of the hospitals. Regionalization simulation analysis was repeated, and the number of deaths was recalculated using this adjustment of hospital case-mix. We also examined the increase in travel distance of patients to the hospitals as a result of the regionalization simulation. RESULTS: In California, 6592 children underwent cardiac surgeries in 1995 to 1997 with 352 in-hospital deaths (overall mortality rate: 5.34%). A quadratic regression model demonstrated that a high surgical volume was associated with a low mortality rate. We found demarcations between low- and medium-volume hospitals at 70 cases per year and medium- and high-volume hospitals at 170 cases per year. With adjustment for hospital case-mix, we found that 41 deaths could be avoided when all patients from low-volume hospitals were referred, and 83 deaths could be avoided when all patients from low- and medium-volume hospitals were referred to high-volume hospitals (overall mortality rate decreased to 4.08%). The average travel distance for pediatric cardiac surgery was 45.4 miles, which increased by 12.7 miles when all surgeries were referred to high-volume hospitals. When only the 733 high-risk patients were referred from low- and medium-volume hospitals to high-volume hospitals, 49 deaths could be avoided, yielding an overall mortality rate of 4.60%. CONCLUSIONS: Theoretical regionalization of pediatric cardiac surgery is associated with a reduction in surgical mortality from 5.34% to 4.08% when all cases were referred to high-volume hospitals, or decrease to 4.60% when high-risk cases were referred. Although regionalization is associated with an important decrease in the number of deaths, it also increases the travel distance for patients. Additional studies on the costs and benefits of regionalization are needed to determine the best strategies to improve outcomes for children who undergo cardiac surgery.

California↗
PubMed2002

Factors associated with prescription drug expenditures among children: an analysis of the Medical Expenditure Panel survey.

OBJECTIVE: Pharmaceutical costs have reached 14% of total health care costs in the United States and continue to rise. Many studies have looked at factors that influence utilization of hospital and ambulatory care services in the pediatric population. This study examines the factors that influence utilization of prescription drugs in the pediatric population. METHODS: Data from the 1996 Medical Expenditure Panel Survey (MEPS) were used in the analysis. A 2-part multivariate regression analysis was conducted using pediatric (ages 0-17) prescription drug expenditures as the dependent variable. Independent variables were constructed using demographic variables, socioeconomic variables, health status, and medical conditions. RESULTS: Black children are less likely than white children to use any prescription drug (odds ratio: 0.67). Similarly, uninsured children are less likely than privately insured children to use any prescription drug (odds ratio: 0.62). Among children who had any prescription drug expenditure in 1996, children who are black, Asian, and Hispanic had lower prescription drug expenditures than children who are white. Children who are uninsured had lower expenditures than children who are privately insured. Children in near-poor families had lower prescription drug expenditures than those in high-income families, even after controlling for insurance status. Children who are covered by Medicaid had comparable prescription drug expenditures to children who are covered by private insurance. CONCLUSION: Socioeconomic characteristics such as race, insurance status, and family income levels had significant impact on pediatric prescription drug expenditures, even after controlling for the influences of health status and medical conditions.

Adolescent↗
PubMed2002

Hospitalizations for Kawasaki disease among children in the United States, 1988-1997.

OBJECTIVE: To evaluate the epidemiologic pattern of Kawasaki disease (KD) in the United States over 10 years. METHODS: The National Inpatient Sample, a stratified national sample of >900 hospitals in 22 states of the United States, was used. Data on hospital discharges from 1988-1997 were analyzed. Patients <18 years of age with a discharge diagnosis of KD were identified. RESULTS: There were 6442 patients with KD admitted to 651 hospitals. Median age at hospital admission was 2 years. Peak incidence by year of age was 1 year old. Children <2 years old accounted for 36.6% of all cases; <5 years old, 75.6%; and <10 years old, 95.6%. The age distribution seems to be wider than reported from Japan. The incidence for children <5 years old was 8.1 per 100 000 people in 1988, and increased to 18.5 in 1997. There were 3905 males (60.6%) and 2537 females (39.4%), for a male-to-female ratio of 1.54. The incidences were higher in winter and spring (December to May) and dropped to a nadir between July and September. No apparent change in seasonal pattern was noted over 10 years. The South census region showed a seasonal change 2 to 3 months ahead of other regions. The overall in-hospital mortality rate was 0.17%. The mortality rate in children > or =10 years (1.4%) was significantly higher in than children <10 years (0.11%). CONCLUSIONS: KD affects mainly children under 5 years of age, with a peak incidence in children 1 to 2 years of age. The incidence of KD was rising over the study period. There is a male predominance. Although KD occurs year-round, the lowest incidence is seen from July through September. Such seasonal variation did not change over the 10 years. Seasonal pattern may vary in different geographic regions. Mortality from KD is rare, although children > or =10 years are at higher risk.

Age Distribution↗
PubMed2002

Clinical management of infants with hypoplastic left heart syndrome in the United States, 1988-1997.

OBJECTIVES: To evaluate changes in the clinical management of infants with hypoplastic left heart syndrome (HLHS) over a 10-year period. BACKGROUND: Orthotopic heart transplantation (OHT) and the Norwood procedure have emerged as the treatment options for HLHS over the last 2 decades. METHODS: We used 1988-1997 hospital discharge data from the National Inpatient Sample dataset. Patients < or =30 days of age with a principal diagnosis of HLHS were identified. Clinical management included the Norwood procedure, OHT, in-hospital death without surgery, discharge home without surgery, and transfer to another hospital. Multivariate logistic regression was used to evaluate variables associated with the choice of management. RESULTS: There were 1986 cases of HLHS with 812 in-hospital deaths, yielding a mortality rate 40.9%. The in-hospital mortality rate decreased from 54.4% in 1988 to 38.1% in 1997. The proportion of patients treated with the Norwood procedure increased from 8% in 1988 to 34% in 1997. The proportion of patients who died in the hospital without surgery decreased over time while the percentage discharged from the hospital without surgery or transferred to another hospital remained relatively unchanged. The in-hospital mortality rate was significantly lower in the OHT group compared with the Norwood group (26.2% vs 46.0%). We found no differences in gender, race, type of insurance, or home income between patients treated with the Norwood procedure compared with those who received comfort care. Patients from a later era, in the South, and in teaching hospitals were more likely to undergo the Norwood procedure. CONCLUSIONS: Between 1988 and 1997, the proportion of infants with HLHS treated with the Norwood procedure increased while the use of comfort care decreased. Gender, race/ethnicity, type of medical insurance, and home income did not correlate with treatment choices.

Cardiac Surgical Procedures↗