The best strategy for red blood cell transfusion in severe burn patients,restrictive or liberal: A randomized controlled trial

IntroductionAlthough blood transfusion is common in burns, data are lacking in appropriate transfusion thresholds. It has been reported that a restrictive blood transfusion policy decreases blood utilization and improves outcomes in critically ill adults, but the impact of a restrictive blood transfusion policy in burn patients is unclear. We decided to investigate the outcome of decreasing the blood transfusion threshold.Material and methodsEighty patients with TBSA > 20% who met our inclusion criteria were included. They were randomly divided into control and intervention groups. The intervention group received packed cells only when Hemoglobin declined to less than 8 g/dL at routine laboratory evaluations. While the control group received packed-cell when hemoglobin was declined to less than 10 g/dl. The total number of the received packed cell before, during and after any surgical procedure was recorded. The outcome was measured by the evaluation of the infection rate and other complications.ResultThe mean hemoglobin level before transfusion was 7.7 ± 0.4 g/dL in the restrictive group and 8.8 ± 0.7 g/dL in the liberal group. The mean number of RBC unit transfusion per patient in the restrictive group was significantly lower than the traditional group (3.28 ± 2.2 units vs. 5.9 ± 3.7 units) (p-value = 0.006). The total number of RBC transfused units varied significantly between the two groups (p-value = 0.014). The number of transfused RBC units outside the operation room showed a significant difference between groups (restrictive: 2.8 ± 1.4 units vs. liberal: 4.4 ± 2.6 units) (p = 0.004). We did not find any significant difference in mortality rate or other outcome measures between groups.ConclusionApplying the restrictive transfusion strategy in thermal burn patients who are highly prone to all kinds of infection, does not adversely impact the patient outcome, and results in significant cost savings to the institution and lower rate of infection. We conclude that the restrictive transfusion practice during burn excision and grafting is well tolerated and effective in reducing the number of transfusions without increasing complications.Clinical Trial Registration ReferenceIRCT20190209042660N1.     

Long-term results in the treatment of menorrhagia and hypermenorrhea with a thermal balloon endometrial ablation technique.

BACKGROUND AND OBJECTIVES: Evaluation of long-term results using a thermal balloon endometrial ablation technique to treat menorrhagia and hypermenorrhea, considered dysfunctional uterine bleedings. METHODS: A single-arm, prospective study with long-term follow-up of 48 months at the department of obstetrics and gynecology, University of Kiel, Germany. Following hysteroscopic evaluation of the uterine cavity and fractionated curettage, the Cavaterm endometrial thermal ablation technique was performed on 70 patients over the age of 40 with menorrhagia and hypermenorrhea in whom medical treatment had previously failed. The study included a group of 10 patients with adenomyosis and uterine fibroids. RESULTS: In 65 patients, a complete 48-month follow-up evaluation was possible: 58% of patients reported amenorrhea and 33% hypomenorrhea. Nine percent of patients remained eumenorrheic. Fifty percent of the small group with failed indications for the procedure had to undergo a hysterectomy. CONCLUSIONS: The Cavaterm thermal coagulation system in the earlier mode of application (15 minutes at a temperature of 70 degrees C and a pressure of 200 mm Hg) is a safe and highly effective method of endometrial ablation resulting in a minimal amount of posttreatment menstrual bleeding.     

Transfer of 45Ca and 36Cl at the blood-nerve barrier of the sciatic nerve in rats fed low or high calcium diets

Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.     

与铁稳态有关的生物分子

根据近几年来发表的与铁稳态有关的生物分子的研究文献 ,将这些生物分子根据其与铁的吸收、转运、储存以及对铁稳态的监控调节等方面的关系 ,对这些生物分子进行了分类。特别是对细胞膜载体、运铁蛋白受体、铁调蛋白及铁反应元件等作了较为详细地论述     

妇科腹腔镜手术几种激光对兔子宫壁损伤的实验研究

为掌握妇科腹腔镜手术所应用的激光器的治疗剂量，对几种激光引起的兔子宫壁热损伤进行观察。实验研究证实：所有激光产生的损伤程度与所用的剂量呈正相关。术后４８ｈ与即刻损伤程度相比，半导体激光的损伤程度明显加深、加宽；但ＣＯ２激光和ＮｄＹＡＧ激光接触式光刀无显著变化。说明应用激光行妇科腹腔镜手术治疗时，所产生的损伤与应用的功率密度有关，为临床合理选用腹腔镜下的激光治疗提供依据     

International round robin tests on the measurement of carbon in diesel exhaust particulates

Object: Diesel soot has been recognized as probably carcinogenic to humans. Elemental carbon (also called black carbon) in soot is considered at the moment as the most significant surrogate to be measured for assessing the exposure to this pollutant. Its analysis is done by combustion in an oven and determination of the CO₂ formed, after elimination of the organic fraction of the soot by heating and/or by solvent extraction. The analysis allows determination of both fractions of the soot: “elemental carbon” (EC) and organic carbon␣(OC). The sum of EC and OC is called TC (total carbon). Method: An informal European coordination group organized two round robin tests on filter samples collected from diluted diesel emissions. The first round (RRT1) was performed on 13 different samples analyzed by ten laboratories. The range of loading was 2.5 to 150 μg/cm² of EC. No evaluation of the precision within laboratories could be made since each laboratory gave only one result per sample. Therefore a second round (RRT2) was organized with two samples and a blank filter sent in several portions to 11 laboratories. It should be stressed that each laboratory used its own method and that no standardization was planned at this stage. Results: Results of RRT1 showed that the coefficient of variation between laboratories decreased with higher loading and was around 10% to 15% for EC above about 20 μg/cm². Dispersion of the results varied and it appeared that the way OC is removed from the soot is probably the most important factor of influence. The correlation between the laboratories was good as a whole but some systematic differences could be detected. Besides the different techniques to remove the organic carbon, the pretreatment of the filter by HCl (either as a vapor or as a solution) to remove the inorganic carbonates (potential interference sources), is probably also a significant factor of influence in the dispersion of the results between laboratories. It is not yet clear from these results whether the “environmental” laboratories give different results from the “occupational” laboratories, but it is clear that their objectives differ since for the “environmentalists”, EC is not a specific marker of diesel immissions, in contrast to the “occupationalists”. Conclusion: It can be concluded that, although significant differences exist between laboratories they can be attributed mainly to the narrow distribution of the results within a single laboratory, and that the overall agreement of the results for EC and TC is fairly good. These results obtained with pure diesel engine emissions, should be complemented by field samples, but they have already achieved relevant findings in the performance of the procedures used to assess exposure to diesel soot. Received: 30 December 1996 / Accepted: 21 February 1997     

Inward rectifying potassium channels in human malignant glioma cells

Human glioma cells obtained from established cell lines (Tp-276MG, Tp-301MG, Tp-378MG, Tp-483MG and U-251MG) were analyzed for the presence of ion channels with the tight-seal voltage clamp technique. The current-voltage relation revealed a marked inward rectification at hyperpolarizing voltages, due to the presence of inward rectifying K-channels in cells from all studied cell lines. These channels were conducting when the membrane potential was more negative than the K-equilibrium potential. The slope conductance for the inward K-currents (g_Ki) was affected both by [K⁺]_i and [K⁺]₀. g_Ki was proportional to [K⁺]₀ raised to 0.35 or 0.50, of which the larger value was measured in the presence of low [K⁺]_i (25mM). The rectification was not significantly different in cells perfused with Mg-free EDTA-buffered internal solution. Tl⁺ was 3.5 times more permaant than K⁺. g_ki was blocked by Cs⁺ (1 mM) in a voltage-dependent way (more effective in the hyperpolarized membrane), and by Na⁺ (154 mM) depending on voltage and time. From measurements of unitary current events in membrane patches (outside out or cell attached) the conductance of the single inward rectifying channel was estimated to be 27 ± 7 pS. This type of ion channel may be important for K-uptake by glial cells and hence for the K-homeostasis in the brain.