Superior vena cava diameters in normal Thai fetuses.

OBJECTIVE: Establish the normative data of fetal superior vena cava (SVC) diameters from 20 to 38 weeks' gestation in Thai fetuses. MATERIAL AND METHOD: Thai pregnant women with normal fetuses were enrolled for 2-dimensional echocardiographic measurements of SVC diameters. All women had good menstrual history and a confirmed gestational age with first or second trimester ultrasound. The SVC diameters were obtained in caval long-axis view in both systolic and diastolic periods. The measurements were plotted against gestational age. The best-fit regression equations were obtained. The 5th, 50th, and 95th percentile were then calculated for each gestational age. RESULTS: Three hundred three measurements were obtained. Regression analysis demonstrated a linear correlation between SVC diameter and gestational age in both early ventricular systolic and end ventricular diastolic periods. The best-fit equations were SVC maximum diameter (mm) = -1.379 + 0.183GA (week), r = 0.889 (p < 0.001), SVC minimum diameter (mm) = -1.194 + 0.134GA (week), r = 0.826 (p < 0.001) at early systolic and end diastolic periods respectively. The calculated values of the SVC diameters across gestational age were presented as 5th, 50th, and 95th percentile. CONCLUSION: SVC diameter increases linearly across gestational age in both ventricular systolic and diastolic periods. These could be a basis for assessment of fetuses with abnormal cardiovascular physiology such as hydrops fetalis and intrauterine growth restriction.

Cord blood collection for the National Cord Blood Bank in Thailand.

Umbilical cord blood is an effective alternative source of hematopoietic stem cells transplantation in children and adolescents. However, the efficacy and safety of cord blood transplantation correlates with the quantity and quality of cord blood. To evaluate the collection systems and processing of cord blood donations, a pilot research program to optimize recruitment, collection and processing of cord blood donations was developed. The present results showed that the quality of the cord blood (volume, total white blood cells (WBC) count, CD34+ and sterility control) collected was satisfactory and discard rate of collecting units (24.2%) were comparable with data reported from other cord blood banks. To find the optimal mode of collection, comparison of 3 cord blood collection methods (Method 1 = Hanging method after delivering the placenta, Method 2 = Aspiration from in utero placenta, Method 3 = Aspiration from in utero placenta and Syringe-assisted aspiration) using the closed system showed that method 3 was the best method but it required more trained personnel and involved a complicated procedure. The National Cord Blood Bank started its activity in 2002 after several years of pre-clinical studies. To date, a number of transplants using cord blood from related and unrelated cord blood (first report in Thailand) donors have been successfully performed.