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Biomedical subjects

K I Yau

Publications and source records attributed to K I Yau.

At least 19 recordsLinked to original sources

Paraplegia: complication of percutaneous central venous line malposition.

Percutaneously inserted central venous lines are usually a safe and effective means of securing prolonged central venous access but can have serious complications. One patient who experienced clinically important morbidity related to inadvertent malpositioning of a central venous catheter is described. It was inserted via the left saphenous vein into the lumbar venous plexus and resulted in milky cerebrospinal fluid, urine retention, and paraplegia. Reviewing the literature, only 11 patients with the same malposition were reported, three of them with percutaneously inserted central venous lines. In these three patients and our patient the left saphenous vein was used. Neurologic sequelae of paraplegia and urine retention were recorded in 25% (3/12) of patients. The mortality rate approached 42% (5/12) but only two patients were related to catheter misplacement. Although the complication rate is extremely low and difficult to recognize, catheter malposition into the ascending lumbar vein can lead to lethal complications.

Catheterization, Central Venous↗

Prognostic indicators of survival in infants with congenital diaphragmatic hernia.

PURPOSE: This study sought to identify the factors predictive of the short-term outcome in infants with congenital diaphragmatic hernia (CDH). METHODS: We retrospectively reviewed medical records from September 1985 to December 1998 for all infants born with CDH and managed at National Taiwan University Hospital (NTUH). Coexisting pathology and measures of respiratory function were analyzed to determine the prognostic factors. RESULTS: A total of 32 infants with CDH were managed at NTUH over the past 13 years. The investigated factors associated with poor prognosis in CDH included congenital heart disease, chromosomal abnormality, pneumothorax, and preoperative parameters including arterial partial carbon dioxide pressure greater than 40 mmHg, arterial partial oxygen pressure less than 100 mmHg, alveolo-arterial partial oxygen pressure greater than 610 mmHg, and oxygen index (OI) greater than 0.4. Multiple logistic regression analyses indicated that only an OI greater than 0.4 and pneumothorax were significant indicators of poor prognosis. When the incidence of pneumothorax was compared between patients who received ventilation using a conventional mechanical ventilator or high-frequency oscillatory ventilator (HFOV), a trend toward a lower incidence of pneumothorax in those using HFOV for initial stabilization was found (p = 0.08). CONCLUSIONS: An OI greater than 0.4 before surgery and pneumothorax are poor prognostic indicators in infants with CDH. A high OI is reflective of the severity of pulmonary dysfunction in infants. Pneumothorax further compromises the dysfunction of a hypoplastic lung in infants with CDH. The results of this study show the importance of avoiding iatrogenic pneumothorax during management of infants with CDH.

Female↗

Prognostic factors for walking attainment in very low-birthweight preterm infants.

The purpose of this study was to compare the age of walking attainment between very low-birthweight (VLBW) preterm infants and normal term infants, and to determine the variables that affect the walking attainment in VLBW infants. Ninety-six VLBW preterm infants and 82 normal term infants were prospectively followed to determine their age of walking attainment and to monitor gross motor development with sequential clinic visits at 6, 9, 12 and 18 months corrected age. Perinatal and sociodemographic data were collected through review of medical records. The VLBW infants were significantly older at attainment of walking (median 14 months) than the term infants (median 12 months) after correction for prematurity. By the age of 18 months, all term infants had attained walking ability; while 11% of VLBW infants were still unable to walk. Multivariate proportional hazards regression analysis revealed that low gestational age was significantly associated with late attainment of walking in VLBW infants. With the adjustment for gestational age, prolonged ventilation (or oxygen therapy) and severe retinopathy of prematurity were significant predictors of late walking attainment. Our findings indicate that VLBW preterm infants have an increased risk of delayed attainment of walking. Furthermore, the contribution of low gestational age to the delayed walking attainment in VLBW infants may occur via the plausible pathways of neonatal respiratory distress and severe retinopathy of prematurity.

Aging↗

Congenital intracranial teratoma.

Congenital intracranial teratoma is a rare disease. A fetus with a congenital intracranial teratoma presenting with a disproportionately enlarged head at 27 weeks gestation is presented. Prenatal ultrasonography and fetal magnetic resonance imaging demonstrate a huge, heterogenous intracranial mass in the left supratentorial region, with the left cerebral hemisphere being compressed and flattened. The infant died of respiratory failure within 24 hours of birth at 28 weeks gestation. On postmortem examination the histologic report revealed an immature teratoma. Fetal MRI is helpful in the prenatal diagnosis and evaluation of intracranial tumor.

Brain Neoplasms↗

Alberta infant motor scale: reliability and validity when used on preterm infants in Taiwan.

BACKGROUND AND PURPOSE: The goal of this study was to examine the reliability and validity of measurements obtained with the Alberta Infant Motor Scale (AIMS) for evaluation of preterm infants in Taiwan. SUBJECTS: Two independent groups of preterm infants were used to investigate the reliability (n=45) and validity (n=41) for the AIMS. METHODS: In the reliability study, the AIMS was administered to the infants by a physical therapist, and infant performance was videotaped. The performance was then rescored by the same therapist and by 2 other therapists to examine the intrarater and interrater reliability. In the validity study, the AIMS and the Bayley Motor Scale were administered to the infants at 6 and 12 months of age to examine criterion-related validity. RESULTS: Intraclass correlation coefficients (ICCs) for intrarater and interrater reliability of measurements obtained with the AIMS were high (ICC=.97-.99). The AIMS scores correlated with the Bayley Motor Scale scores at 6 and 12 months (r=.78 and.90), although the AIMS scores at 6 months were only moderately predictive of the motor function at 12 months (r=.56). CONCLUSION AND DISCUSSION: The results suggest that measurements obtained with the AIMS have acceptable reliability and concurrent validity but limited predictive value for evaluating preterm Taiwanese infants.

Child Development↗

Urinary uric acid/creatinine ratio as an additional marker of perinatal asphyxia.

PURPOSE: To study the validity of urinary uric acid (UA) as a marker of perinatal asphyxia in term and premature infants. METHODS: The urinary ratio of UA to creatinine (Cr) was obtained within 24 hours after birth in four groups of infants: 17 term infants and 18 premature infants with perinatal asphyxia, and 22 healthy term infants and 20 premature infants without perinatal asphyxia. Perinatal asphyxia was defined as an Apgar score of 3 or less at 1 minute or 5 or less at 5 minutes, and/or a first blood gas pH of less than 7.25 and a base deficit of at least 12 mmol/L. RESULTS: The urinary ratio of UA to Cr was significantly higher in term infants with perinatal asphyxia than in term infants without asphyxia (1.53 +/- 0.71 vs 0.73 +/- 0.45; p < 0.005). The same result was found between premature infants with and without perinatal asphyxia (3.89 +/- 1.84 vs 2.45 +/- 0.88; p < 0.01). The urinary ratio of UA to Cr in premature infants was significantly higher than in term infants. When the urinary ratio of UA to Cr was greater than 0.95, perinatal asphyxia was identified with a sensitivity of 80% and a specificity of 71% in term infants. In premature infants, a cut-off value of UA/Cr for perinatal asphyxia of 2.9 had a sensitivity of 71% and a specificity of 70%. CONCLUSIONS: The results of this study indicate that the urinary ratio of UA to Cr may be used as an additional marker of perinatal asphyxia in term and premature infants. In comparison with other markers such as xanthine, hypoxanthine, and ascorbic acid, it is a simple, quick, and inexpensive way to detect hypoxic episodes in a neonatal intensive care unit within 24 hours after birth.

Asphyxia Neonatorum↗

Granulocyte colony-stimulating factor in the cord blood of premature neonates born to mothers with pregnancy-induced hypertension.

OBJECTIVES: To estimate the cord blood levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in preterm infants and to study the relationship of these levels to pregnancy-induced hypertension (PIH) and absolute neutrophil counts. STUDY DESIGN: G-CSF and GM-CSF levels in the cord blood of preterm neonates (n = 74) either with or without maternal PIH were estimated by enzyme-linked immunosorbent assay. RESULTS: Infants in the PIH group had lower white blood cell, absolute neutrophil, absolute lymphocyte, and monocyte counts. The levels of G-CSF in cord blood were significantly lower in infants whose mothers had PIH (P =.04) and in infants with neutropenia (P =. 01). G-CSF levels were positively correlated with both absolute neutrophil count (P =.02) and total white blood cell count (P =.01). GM-CSF was undetectable in all subjects. According to logistic regression with neutropenia as the dependent variable, only maternal PIH (P <.001), gestational age (P <.001), and G-CSF (P =.01) were independently related. CONCLUSION: In this study maternal PIH and low gestational age were significantly associated with neutropenia in premature infants. Low G-CSF levels may contribute to the neutropenia that is commonly seen in infants born to mothers with PIH.

Case-Control Studies↗

Power Doppler ultrasound imaging in neonatal cerebral venous sinus thrombosis.

Neonatal sinus thrombosis is a rare occurrence in sick neonates. Because of its nonspecific manifestations, the incidence is underestimated. This disease may not be demonstrated by conventional color Doppler and is diagnosed by computed tomography or magnetic resonance imaging. The authors report a neonate with neonatal sinus thrombosis diagnosed by power Doppler and suggest that the technique may be used as a less expensive and more available screening and follow-up method in high-risk neonates.

Female↗

Factors predisposing infants to lower respiratory infection with wheezing in the first two years of life.

BACKGROUND: Acute lower respiratory illness (LRI) early in life has been implicated as a factor for adverse respiratory outcomes later in life. Factors that predispose infants to LRI with wheezing have not been conclusively defined. OBJECTIVES: This prospective study assessed factors that might contribute to LRI with wheezing in the first 2 years of life. METHODS: Seventy-one healthy full-term infants (44 boys, 27 girls) completed the 2-year follow-up. Demographic and environmental factors were evaluated by questionnaire. Respiratory function was assessed by single occlusion technique and rapid thoracic compression technique. Both techniques were performed successfully in 40 infants at 2.6 (+/- 1.4) months old before they developed any episode of LRI. RESULTS: Eighteen infants (25%) developed LRI with wheezing. The first episode of LRI with wheezing occurred in the first year of life in 8 infants, and in the second year of life in 10 infants. There were no significant differences in the demographic or environmental features between infants with or without wheezing LRI, or between infants who acquired LRI with wheezing in the second year of life and those who did not acquire or acquired in the first year of life. Infants from different groups did not differ in airway resistance or maximal flow at functional residual capacity. Infants who developed LRI with wheezing had higher incidence of low values for total respiratory system compliance corrected for body weight compared with those who did not (5/30 versus 6/10, odds ratio = 7.5, 95% confidence interval: 1.53 to 36.7, P = .013). None of the variables of the pulmonary function test could differentiate infants who subsequently developed LRI with wheezing in the first year of life or did not develop any episode of LRI with wheezing from those who developed LRI with wheezing in the second year of life. CONCLUSIONS: Differences in lung function in early life may predispose infants to LRI with wheezing in the first 2 years of life.

Acute Disease↗

Effects of prokinetic agents on contractile responses to electrical field stimulation of isolated guinea pig trachea.

We investigated the effects of two prokinetic agents, metoclopramide and cisapride, on the contractile response of isolated guinea pig tracheal segments exposed to electrical field stimulation (EFS). Tracheal segments were suspended between two platinum electrodes in organ baths. Frequency-response curves were obtained by increasing the frequency of the stimuli on equilibrated tracheal segments, in a stepwise manner. Metoclopramide potentialed the EFS-induced contraction of the tracheal; the potentiation was more prominent at lower stimulation frequencies (< or = 10 Hz). Cisapride significantly inhibited the electrically stimulated contraction in trachea strips when the frequency of the stimulus was higher than 10 Hz. In the presence of both metoclopramide and cisapride, there was a potentiation of the contractile response at lower frequencies, and this potentiation was reduced when the frequency was higher than 10 Hz. These results demonstrate that metoclopramide enhances and cisapride reduces the airway tonicity elicited by EFS in isolated guinea pig trachea segments. Further studies are needed to verify the effects of these prokinetic agents on EFS-induced contraction of isolated guinea pig trachea and to determine the mechanisms involved.

Animals↗

Neurobehavioral development at term in very low-birthweight infants and normal term infants in Taiwan.

We compared the neurobehavioral performance at term between very low-birthweight (VLBW) infants and term infants in Taiwan, and investigated the relationships between neonatal factors and neurobehavioral performance in VLBW infants. Sixty VLBW infants and 58 healthy term infants were examined using the Neonatal Neurobehavioral Examination-Chinese version (NNE-C) at 40 weeks postmenstrual age. Medical records of the VLBW infants were reviewed to assess neonatal factors. The mean total score of the preterm infants (67.4+/-5.0) was significantly lower than that of the term infants (73.8+/-3.0) (t = 8.51, P < 0.0001). Furthermore, respiratory illness had a marginal effect on the rate of low neurobehavioral score (defined as 2SD below the mean score of term infants) in the preterm infants after adjustment for gestational age (odds ratio = 7.67, chi2 = 3.36, P = 0.067). Our findings indicate that preterm infants have lower neurobehavioral scores at term than their healthy term counterparts. Furthermore, respiratory illness may be a potential risk factor for low neurobehavioral score at term in preterm infants when gestational age is adjusted for.

Apgar Score↗

The controversy regarding diagnostic criteria for early myoclonic encephalopathy.

To re-evaluate the diagnostic criteria for early myoclonic encephalopathy (EME), the following study was done. During the past 2 years, five patients with erratic, fragmentary myoclonus of neonatal onset, in association with other types of seizures, were analyzed with regard to etiologies, electroclinical features and their evolution, using a series of examinations including electroencephalographies (EEGs) and metabolic investigations. Of these five patients, three were diagnosed to have non-ketotic hyperglycinemia (NKH); one was pyridoxine-dependent; the other was cryptogenic. Only two cases (one NKH and one cryptogenic) had initial typical suppression-burst (S-B) EEG pattern, which subsequently evolved into multiple paroxysmal abnormalities with random asynchronous attenuation (MP-AA) pattern. The other two cases with NKH had MP-AA EEG pattern throughout both awake and sleep recordings in two consecutive EEG studies. All three cases with NKH survived with increasing microcephaly, muscle tonicity; all developed infantile spasm with hypsarrhythmia on EEGs. The patient with pyridoxine-dependency had an initial MP-AA EEG pattern, which converted into S-B pattern after the first use of pyridoxine, eventually becoming normal after a supplement with the second-dose of pyridoxine. In conclusion, either S-B or MP-AA pattern may reflect the severity of the underlying pathologies or the disease stages. These results suggest that, from both etiological and electroclinical viewpoints, EME may represent a broader spectrum than previously recognized. The still ongoing controversy regarding whether the S-B pattern should be recognized as the sole EEG criteria for the diagnosis of EME needs further experience to clarify.

Age of Onset↗

The human tail.

The human tail is a congenital anomaly with a protruding lesion from the lumbosacrococcygeal region. A newborn with a tail-like structure over the coccygeal area observed since birth is presented. Lipoma accompanied by tethered spinal cord were found. In reviewing the literature from 1960 to 1997, 59 cases were described. Higher incidences of spinal dysraphism (49.15%) and tethered spinal cord (20.34%) compared with previous reports were evident. This fact plays an important role in understanding the disturbance of development and regression of human tails. A new classification according to whether the anomaly appears in combination with spinal dysraphism is proposed for clinical usage. Preoperative detailed image studies are needed to clarify the possibility of tethered spinal cord syndrome developing in the future and thus prevent it. Magnetic resonance imaging is the modality of choice if available. Long-term follow-up for possible sequelae after operation, especially in cases with spinal dysraphism, is necessary.

Animals↗

The use of prophylactic intravenous immunoglobulin therapy in very low birthweight infants.

BACKGROUND: Nosocomial infections are a major cause of death in premature infants, especially in very low birthweight (VLBW) infants. The VLBW infants have low serum immunoglobulin G levels, which may have an effect on infections in early infancy. Thus, prophylactic administration of intravenous immunoglobulin (IVIG) is proposed to maintain higher immunoglobulin G and reduce the rate of hospital-acquired infection. MATERIALS AND METHODS: A study for the effects of prophylactic IVIG therapy in VLBW infants was performed. A total of 61 VLBW infants were enrolled, and divided into the IVIG group (n = 31) and the control group (n = 30). The dose for each infant was 750-1000 mg/kg for those whose birthweight was less than 1000 g, and 500-750 mg/kg for infants whose birthweight was between 1001 and 1500 g. The control group received saline infusion. The infusions were given every 2 weeks until the infant weighed 1800 g, or was discharged. RESULTS: The results showed: there were no major differences in the perinatal and neonatal characteristics between the two groups, consistently higher IgG levels were found in the IVIG group, and the age of first documented sepsis was earlier in the control group. CONCLUSION: In this study, the prophylactic IVIG therapy may give substantially higher IgG levels, which may last for 2 months. However, a prophylactic effect for hospital-acquired infections was not observed.

Cross Infection↗

Etiology and outcome of hydrops fetalis.

Hydrops fetalis is a morbid condition caused by a wide variety of diseases. Although treatment for some underlying pathologies is becoming available, the prognosis remains poor. To analyze the etiology and outcome of hydrops fetalis, we reviewed the records of 79 fetuses encountered at the National Taiwan University Hospital between January 1993 and October 1996. The mean +/- standard deviation gestational age at presentation was 24.9 +/- 6.3 weeks. One case was due to RhE incompatibility. Seventy-eight fetuses were diagnosed as having nonimmune hydrops fetalis; this was idiopathic in 20 fetuses. In the other 58, the causes and associated conditions were classified into eight groups: hematologic (25), cardiovascular (15), chromosomal (5), gastrointestinal (4), cystic hygroma (3), pulmonary (2), infection (2), and miscellaneous (3). One fetus with cystic hygroma also had a chromosomal abnormality (Turner's syndrome). The most common cause of nonimmune hydrops fetalis was homozygous alpha-thalassemia (31%). Twenty-nine fetuses were lost to follow-up after initial evaluation and 50 fetuses were delivered at our hospital. Of these, there were eight cases of antepartum death, 24 cases of intrapartum death, and 18 live births. Seventeen of the live-born infants were treated at our neonatal intensive care unit, of whom only seven survived.

Adult↗

Early outcome of extremely low birth weight infants in Taiwan.

We retrospectively evaluated the outcome and the risk factors for mortality among extremely low birth weight (ELBW) infants born at National Taiwan University Hospital. The records of all live-born infants with body birth weight of less than 1,000 g from January 1, 1993, to December 31, 1996, were evaluated. Infants with major anomalies or whose parents refused resuscitation were excluded from the analysis. There were 81 ELBW infants (0.59%) among a total of 13,835 live births during the study period, and 73 cases were enrolled for study. The mean gestational age (GA) was 27.2 (range, 24-34) weeks. Sixty-six percent of the ELBW infants were born by cesarean delivery. Respiratory distress syndrome occurred in 64% of infants and exogenous surfactant therapy was given to 47%, while intermittent mandatory ventilation was given to 85%. Symptomatic patent ductus arteriosus occurred in 34% of infants, septicemia in 30%, chronic lung disease in 48%, grade III to IV intraventricular hemorrhage in 27%, stage III to V retinopathy of prematurity in 33%, and necrotizing enterocolitis in 8%. Neonatal survival was 74%, survival to discharge was 60%, and intact survival was 50%. The survival rate was 40% for infants with a birth body of weight less than or equal to 750 g, and 68% for those with a birth body weight of greater than 750 g. While survival was 27% for infants with a GA of less than 26 weeks, it was 75% for those with a GA of greater than or equal to 26 weeks. The survival rate improved year by year for those with a GA less than 28 weeks. Cox regression analysis of survival showed that Apgar score at 1 minute (p = 0.0063), pulmonary hypertension (p = 0.012), and severe intraventricular hemorrhage (p = 0.0031) were the most important factors associated with mortality. Though the outcome of ELBW infants in our institute seems poorer than in some more developed countries, it is improving. The prognosis for ELBW infants of 24 to 25 weeks' GA remains guarded under our present care.

Female↗

Mature teratoma arising from an intra-abdominal undescended testis presenting as a fetal abdominal mass.

Teratoma of the intra-abdominal testis is a rare finding in infants. We describe the case of a full-term newborn treated for a calcified abdominal mass which was observed unexpectedly on prenatal sonography. An undescended right testis was also noted. During laparotomy, a twisted retroperitoneal tumor was found just above the right deep inguinal ring. Histological analysis revealed a mature teratoma of the intra-abdominal right testis. The tumor was removed and there was no recurrence at follow-up 1 year later. A teratoma should be considered in cases of fetal abdominal mass, especially when the testes cannot be detected in the scrotum by the 8th month. Prenatal sonographic diagnosis might be possible.

Adult↗