小体重先天性心脏病患儿的体外循环管理

目的：回顾我院16例小体重先天性心脏病患儿的体外循环(CPB)状况,总结其灌注技术。方法：对我院1995-1996年的16例小体重先天性心脏病患儿临床资料及CPB情况(人工心肺机类型、预充液组成、CPB操作步骤、CPB时间、升主动脉阻断时间、心肌保护等)做一回顾性总结。结果：16例患儿。年龄5个月。2岁,平均1．2岁;体重4.5-9.5kg,平均8．2kg。CPB时间32-284min(平均92min),升主动脉阻断时间14-121min(平均64min)。冷晶体高钾停搏液经滚压泵自主动脉根部间断灌注较好的保护了心肌。结论：适宜的血液稀释,根据不同疾病选择正确的灌注方法,良好的术中管理及心肌保护,可有效的使小体重先天性心脏病患儿在CPB中平稳过渡,减少术后的并发症和死亡率。     

低分子肝素治疗老年人不稳定型心绞痛的疗效分析

目的 观察低分子肝素治疗老年人不稳定型心绞痛的疗效。方法 将１０１例不稳定型心绞痛患者随机分为Ａ、Ｂ两组。在常规治疗基础上Ａ组给予低分子肝素腹部皮下注射;Ｂ组给予等量生理盐水皮下注射。结果 Ａ组心绞痛发作频率比Ｂ组明显减少（Ｐ〈０．０１）。心电图ＳＴ段及Ｔ波较对照组明显改善。Ａ组总有效率９０％,Ｂ组总有效率５４％（Ｐ〈０．０１）。Ａ、Ｂ组治疗期间均未见出血等副作用。结论 低分子肝素治疗老年人不稳定     

Receipt of Recommended Prenatal Interventions and Birth Weight Among African-American Women: Analysis of Data from the 1988 National Maternal and Infant Health Survey

Objectives: While the importance of exploring and better measuring elements of prenatal care have been noted in the public health literature, the components and timing of such services have been poorly examined for the overall pregnant population and specifically for African-Americans, who traditionally have had higher rates of low birth weight and premature delivery. This study explores the association between patient receipt of selected recommended prenatal care interventions and infant birth weight in a nationally representative sample of African-American women, while controlling for the influence of low birth weight risk indicators. Method: This is a retrospective case-control analysis using survey data of women who delivered normal birth weight, moderate low birth weight, and very low birth weight newborns in 1988. A sample of 3905 African-American women who responded to the 1988 National Maternal and Infant Health Survey is examined based on maternal recall of receipt of six clinical screening procedures and seven health-promotion recommendations. Birth weight measures were obtained from linked 1988 birth certificate data. Results: The initial results indicated that women who do not receive all of the recommended health-promotion advice are more likely to deliver very low birth weight infants than women who receive all of the advice in the content of their prenatal care, after controlling for low birth weight risks (OR = 1.28; 95% CI = 1.01, 1.7). However, when breast-feeding advice is removed from the aggregation of health-promotion advice, the significant effect of advice on very low birth weight is negated. No other significant group variations in the receipt of clinical screening procedures or health-promotion advice for women who gave birth in the remaining birth weight categories are observed. Conclusions: Nationally recommended initial clinical screening procedures and health-promotion advice in prenatal care content do not appear to be associated with a reduction in low birth weight for African-American women. More research is needed to better assess the impact of other antenatal interventions, particularly those given to women with a higher prevalence of poor birth outcomes.     

A comparison of perinatal mortality between ethnic Chinese and ethnic whites: Why the Chinese rate was lower

Objectives. To confirm the observation that has been occasionally reported in the literature that perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and to assess the reasons for this lower perinatal mortality rate.

Methods. Secondary‐analysis based on published data.

Results. This exercise demonstrates that the perinatal mortality rate was lower in ethnic Chinese than in ethnic whites. The birth weight distribution in ethnic Chinese was more favourable with reduced births at two extremes of the distribution, and the exposure to risk factors for perinatal death by their mothers was also lower.

Conclusion: Perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and the lower perinatal mortality rate in ethnic Chinese is probably caused by their favourable birth weight distribution and lower exposure to risk factors of perinatal death by their mothers.     

Deciduous enamel defects in low-birth-weight children: correlated X-ray microtomographic and backscattered electron imaging study of hypoplasia and hypomineralization

Enamel does not remodel, and disturbances occurring during development may remain in the tooth as a permanent record of the upset. Mineralization in prenatal and postnatal deciduous enamel was studied in the shed deciduous incisors of low-birth-weight (LBW: < 2kg) children. The specific objective was to gain further insight into the mechanism of formation of developmental defects of enamel. Sections at a resolution of 22–40 m were reconstructed using X-ray microtomography (CT) giving absolute measurements of linear absorption coefficient for AgK radiation. Detail to ca. 1 m resolution was obtained using automated, digital backscattered electron (BSE) imaging of PMMA-embedded material. Matching the histograms of BSE and CT images made possible the calibration of the mean atomic number-dependent signal in the BSE images. The comparison of abnormal, affected enamel regions and post-recovery, normal, unaffected regions could be made in the same teeth, since these zones were easily recognized from the distribution of hypoplasia and hypomineralization. The CT values, converted to calculated mineral densities, ranged from 2.3 g cm^-3 to 2.6 g cm^-3 in LBW hypoplastic, and between 2.65 and 2.78 g cm^-3 in control primary enamel and post-defect, post-natal LBW enamel. Hypoplasia with or without minimal hypomineralization indicated recovery of the ameloblasts in the maturation phase. Disturbance during late matrix formation and early maturation resulted in hypoplasia and hypomineralization.     

Prospective randomized clinical study in general surgery comparing a new low molecular weight heparin with unfractionated heparin in the prevention of thrombosis

A prospective, randomized, controlled clinical trial was performed comparing the antithrombotic efficacy of the low molecular weight heparin LMWH 21–23, (Braun) with an unfractionated heparin in elective general surgical patients over an observation period of 7 postoperative days. A total of 230 patients were admitted: 103 (group I) received low molecular weight heparin and 100 (group II) low-dose unfractionated heparin treatment given subcutaneously. In group I 41 patients (46%) were operated on for malignant disease and in group II 54 patients (54%). Due to the large amount of great abdominal procedures the intra- and perioperative application of hydroxyethyl starch was allowed for volume substitution. None of the patients died due to fatal pulmonary embolism. In group I four patients revealed positive ¹²⁵I-labeled fibrinogen uptake (3.9%); two patients belonged to the hydroxyethyl starch subgroup. In group II five patients displayed a positive fibrinogen uptake (5%); two belonged to the hydroxyethyl starch subgroup. The results of the hemostaseological investigations (e.g., prothrombin time, activated partial thromboplastin time, thrombin clotting time, fibrinogen, antithrombin III, protein C, plasminogen, ₂-antiplasmin , tissue-type plasminogen activator, plasminogen activator inhibitor) revealed no statistically significant differences between groups I and II or their subgroups, although a tendency to prolonged clotting times was observed. The antifactor Xa activity values, however, displayed a statistically significant difference between the two groups (P < 0.05). The antifactor Xa activity measured up to 0.16 U/ml for the low molecular weight heparin (group I) and 0.05 U/ml for the unfractionated heparin (group II) in the postoperative period. Major bleeding complications were not encountered in this study. Fundamental for the low incidence of thrombosis, the additive administration of hydroxyethyl starch appeared in almost one-third of the patients in both study groups.Abbreviations APTT activated partial thromboplastin time - aXa anti-factor Xa - DVT deep venous thrombosis - FUT ¹²⁵I-labeled fibrinogen uptake test - HES hydroxyethyl starch - LMWH low molecular weight heparin - PE pulmonary embolism - UFH unfractioned heparin     

Comparison of autonomic function using Valsalva ratio and 30:15 postural ratio prior to and after haemodialysis treatment

In published studies of chronic haemodialysis patients, the frequency of autonomic dysfunction varies widely. One reason for the variation may be the time of testing with respect to time of dialysis. The current study tests the hypothesis that autonomic function — as measured by heart rate responses to the Valsalva manoeuvre (Valsalva ratio) and 30:15 electrocardiogram (ECG) R—R interval to upright posture (postural ratio) — is different when patients are above dry weight (predialysis) than when they are at or below dry weight (postdialysis). The study also reviews available literature to analyze other factors that may affect the results of autonomic testing in this population. A total of 25 chronic haemodialysis patients underwent standard Valsalva and 30:15 R—R interval postural autonomic testing prior to and after haemodialysis. In addition, pre- and postdialysis orthostatic responses were measured and compared with a control population. The 30:15 ratio increased after dialysis (p = 0.001). The Valsalva ratio did not change with dialysis. Out of 25 subjects, seven had an abnormal 30:15 ratio prior to dialysis decreasing to two out of 25 patients postdialysis (p < 0.03). Orthostatic responses predialysis did not differ from those in the control group. Review of the literature shows great variability in definition of normal Valsalva and postural (30:15 R—R interval) ratios. Diabetic patients in the current and prior studies were more likely to have abnormal responses. In conclusion, the prevalence of autonomic dysfunction in chronic dialysis patients as determined by Valsalva and 30:15 ECG postural ratios may be influenced by the following factors: when subjects are studied with respect to their dialysis treatment; the number of subjects with diabetes; and the cut-off point used to define abnormal test results. Abnormal Valsalva ratios are less frequent when measured postdialysis.     

Solute Absorption from the Airways of the Isolated Rat Lung. IV. Mechanisms of Absorption of Fluorophore-Labeled Poly-α,β-[N(2-Hydroxyethyl)-DL-Aspartamide]

The pulmonary absorption kinetics of a single molecular weight distribution (MWD) of fluorophore-labeled poly-,-[N(2-hydroxyethyl)-DL-aspartamide] (F-PHEA), a hydrophilic and biocompatible synthetic polypeptide, were studied in the isolated, perfused rat lung (iprl) as functions of administered polymer concentration, dose, vehicle, and presence and absence of fluorophore. The MWD was characterized before and after absorption by measurement of weight- and number-averaged molecular weights (M _wand M _n, respectively) using high-performance gel-permeation chromatography. Values for M _w and M _n were 8.6 and 5.3 kD before, and 6.7 and 4.7 kD after, absorption into the perfusate; there was no significant metabolism and the MWD of the absorbed polymer was independent of both dose and sampling time over a 3-hr period. F-PHEA failed to show any evidence of aggregation in solution or changes in dose distribution within the airways as functions of increasing polymer concentration and dose. A concentration ranging study indicated the presence of a saturable, carrier-mediated transport process for F-PHEA with a maximum absorption rate, V _max, of approximately 180 µg or 0.027 µmol/hr. Coadministration of fluorophore-free PHEA was capable of depressing the absorption of F-PHEA. The transport process for F-PHEA appeared to have a molecular weight limit of about 7 kD for this hydrophilic polymer.     

Nutrient Intake following Vertical Banded Gastroplasty or Gastric Bypass

Background: This study explored eating habits, nutrient intake, and blood vitamin and mineral levels to determine whether severely obese subjects (BMI 40-50 kg m⁻²) post-vertical banded gastroplasty (VBG) or gastric bypass Roux-en-Y (GBR) are at risk of developing compounded under-nutrition. Methods: A dietary follow-up of 36 VBG and 19 GBR was maintained for 18 months via 7-day food intake diaries and 24-h recalls. Food intake was analysed for energy and nutrient composition and for its relative amount to recommended dietary allowances (RDA). Results: Weight loss was greatest during the first 6 months, continued at a slower rate for the next 6 months, nearly ceasing thereafter. The results following GBR were not substantially different from those following VBG 18 months postoperatively. The median weight loss at 1 year postoperatively was 48, 46, 48 and 36 kg; expressed as residual excess body weight: 0.2, 16, 13 and 22% for GBR Men, Women, VBG Men, Women, respectively. According to the classification proposed by Reinhold, all subjects achieved excellent treatment outcomes 18 months postoperatively. Despite the relatively low reported energy intake (20-50% below RDA), no correlation was found between rate of weight loss and energy intake at 6 months postoperatively. The intake of most vitamins and minerals was below 50% of RDA during the 18 months follow-up. The increase in energy intake did not improve the level of the nonenergy-contributing nutrients. Compliance to multivitamin and mineral supplement intake deteriorated with time. Conclusion: The low to within-normal range of blood vitamin and mineral levels 12 months postoperatively suggests the slow development of subclinical nutritional deficiency which could jeopardize the subjects' long-term health status.