Economic considerations at the threshold of viability

Neonatal intensive care for infants born at 22–24 weeks has become more prevalent in the past three decades, but outcomes remain highly variable between centers, in part due to different approaches in management. With this increased frequency of intervention, there has been concern for a concurrent increase in costs of care for survivors. This article reviews the direct medical, direct non-medical, and indirect costs of care for periviable infants and their families, as well as the current limitations of published data. In addition, we highlight the cost-effectiveness of neonatal intensive care and various therapies offered to extremely preterm infants, while also considering the ethical dilemmas inherently tied to periviable decision-making. Strategies to improve the gaps in knowledge on the economic impact of the smallest infants are discussed.     

改良头位分娩评分法识别头位难产临床应用价值的研究

目的:探讨改良头位分娩评分法用于识别头位难产的可行性及临床应用价值。方法:应用改良头位分娩评分法对625例足月分娩的初孕产妇适时评分,采取相应措施,选择正确分娩方式。结果:改良头位分娩评分法与头位分娩评分法比较,其识别头位难产的敏感性和特异性较高,误诊和漏诊较少。影响头位分娩的诸因素中先露下降、宫口扩张、胎位、宫缩强度、活跃期长短与难产相关性较大;改良法临产评分≤50分者, 69. 5%需行剖宫产术, >50分者, 94. 82%经阴道分娩,与头位分娩评分法比较,改良法与分娩结局更吻合;不同分娩方式处理后,改良法评分均有不同程度地提高,提高越明显,自然分娩几率越高。结论:改良头位分娩评分法将影响分娩的诸因素进行量化评分,能更及时、准确地判断头位顺产或难产,正确选择分娩方式,减少了产科并发症。     

脐血乳酸水平、产时胎心监护不良图形和新生儿结局关系的研究

目的:研究脐动脉血乳酸水平与产时胎心监护不良图形及新生儿结局之间的关系。方法:229例足月妊娠、单胎、头位产妇根据产时胎心宫缩图(cardiotocography,CTG)分为两组,观察组:轻度变异减速(variable deceleration,VD)68例、不良CTG包括中、重度VD、不典型VD、胎心基线变异减弱或消失、延长减速、重度晚期减速及心动过缓84例。对照组:产时CTG无VD及不良图形、新生儿脐动脉血pH≥7.20的产妇77例,检测新生儿脐动脉血乳酸浓度及生后20项行为神经评分(neonatal behavioral neudogioal as-sessment,NBNA)。结果:对照组脐动脉血乳酸99%参考值范围为1.31~4.05mmol/L,不良CTG脐血乳酸水平明显高于对照组(P<0.01);pH、BE值显著低于对照组与轻度VD组(P<0.01,P<0.05),脐血乳酸水平与pH、BE呈显著负相关(P<0.01)。以对照组x-±2.58s为界值,观察组脐血乳酸超过界值者不良CTG占73.33%,其中不良结局儿占68.18%。结论:脐动脉乳酸水平与pH、BE值有较好的相关性。产时重度VD或VD并存其它异常CTG,胎心基线变异减弱,尤其伴发羊水粪染、脐带异常时与围生儿脐血高乳酸水平、不良结局有关。     

口服米索前列醇混悬液用于足月妊娠引产70例分析

目的 探讨小剂量口服米索前列醇混悬液用于足月妊娠引产的有效性和安全性。方法 １４０例有引产指征的足月孕妇分为两组。Ａ组７０例口服米索混悬液,每２ｈ１次,初起每次２０ｍｌ,连续３次后若无规律宫缩出现,第４次起改为每次４０ｍｌ,若出现有效宫缩即停药,否则直至服守２００ｍｌ;Ｂ组７０例静滴催产素引产作为对照组。结果 两组引产成功率分别为８８．５７％和８２．８６％（Ｐ〉０．０５）。Ａ组从开始用药至监产的平     

蛛网膜下腔-硬膜外联合阻滞麻醉用于分娩镇痛效果观察

目的 探讨两种分娩镇痛方法的效果．方法 采用蛛网膜下腔及硬膜外腔联合给予低质量浓度麻醉药及镇痛药和单纯硬膜外腔阻滞的方法分别对３０例实产妇进行分娩镇痛,比较组的镇痛效果,不良反应及对产程,分娩方式,产后出血量,胎儿及新生儿等的影响,并与５０例正常未干预组产妇比较。结果 联合组效果较好,单纯组镇痛作用欠佳且增加阴道分娩的助产率。     

Whom are we seeking to protect? Extremely preterm babies and moral distress

Advances in perinatal care bring with them ethical challenges and difficult questions. When should we provide life-sustaining interventions, and who should decide? Particularly at the edges of viability, some clinicians may feel required to provide a level of care that they believe is not in the patient's interests, resulting in moral distress.This article will discuss the complex nature of moral distress arising during the care of extremely preterm babies. It will describe the challenges and cognitive biases present when contemplating potential harms to the baby and recognize the possible costs to both healthcare provider and baby when moral distress arises. Both clinicians caring for extremely preterm babies and the families themselves can experience moral distress. This article argues that for clinicians, recognizing the range of possible sources of moral distress is vital in order to appropriately address moral distress. Moral distress may arise from a desire to protect the baby, but also from an impulse to protect oneself from the emotional burdens of care. Addressing moral distress requires reflection on the factual beliefs, experiences and personal values which lie behind the distress, both within oneself and in discussion with colleagues. Moral distress indicates that a situation is ethically challenging, but it does not necessarily mean that a wrong decision has been made.     

SLC11A1 is expressed in the human placenta across multiple gestational ages

The human placenta functions as an innate immune barrier to prevent fetal infection. However, the molecular mechanisms accounting for placental resistance to pathogens are currently poorly understood. The solute carrier family 11 member 1 (SLC11A1) is a divalent cation transporter expressed primarily by macrophages and neutrophils that is essential for controlling infections by intracellular pathogens such as Salmonella, Leishmania and Mycobacteria. This report demonstrates that SLC11A1 is expressed in the syncytiotrophoblast of the human placenta at multiple gestational ages. These results suggest that SLC11A1 may play a role in blocking productive placental infections by certain intracellular pathogens.     

腹腔镜术中不同时期气腹压力对循环呼吸及血气参数的影响

对３０例腹腔镜妇科手术病人分别观察在正常腹压、气腹压１３～１９ｋＰａ、气腹压２０～２７ｋＰａ三个不同时期腹压下循环、呼吸、血气参数的变化。结果显示：潮气量（ＴＶ）、气道峰压（Ｐｐｅａｋ）、呼气末ＣＯ２浓度（ＰｅｔＣＯ２）、二氧化碳分压（ＰａＣＯ２）、动脉血氧分压（ＰａＯ２）变化明显，比较在不同腹压下的参数相差显著或非常显著（Ｐ＜００５或００１）。提示：气腹压力超过２ｋＰａ对循环、呼吸影响较严重，尤其是妇科手术所致的特殊体位改变。因此，控制适当的气腹压对病人在术中的安全是至关重要的。     

La somnolence chez les adolescents: étiologie et conséquences multiples

Over the past century a dramatic decline in sleep duration among adolescents, such as more than one hour of sleep loss per night, has been reported. A debt in sleep duration could lead to sleep deprivation, a major risk factor associated with daytime sleepiness. Sleepiness refers to the inability to maintain an adequate level of alertness during the day which may result in more or less being able to control falling asleep at inappropriate times. This literature review updates on sleepiness regarding its characteristics, etiology and consequences on adolescents. Studies revealed that from 25 % to 78 % of adolescents had reported sleepiness. Its manifestations may include heavy lids, yawns, difficulties to concentrate and emotional irritability. In addition, while it is recommended that adolescents under 18 years-old should sleep from eight to ten hours a night, only 63 % of them actually do so. The etiology of sleep deprivation and sleepiness in this population can be explained by various biological and societal factors. First, the sleep-wake cycle of adolescents shows a biological shift from the beginning of pubertal maturation, described as a perfect storm. It refers to a social jetlag by going to sleep and waking up later and accumulating a sleep debt during weekdays which they try to reimburse during weekends. This phenomenon can be explained by physiological changes such as a slower accumulation of sleep pressure. In addition to this perfect storm, environmental and societal factors contribute to the social jetlag and reduce sleep duration in adolescents. Screen exposure before bedtime can delay sleep and wake onset, which is a risk factor for sleeping debt. Substance use such as caffeine, cigarettes or electronic vaporizer, ADHD or freely available medication, alcohol, cannabis use or drug consumption could further disrupt sleep-wake cycle by stimulating, depressing or otherwise disrupting the central nervous system. Early, before 8:30 am, class start times have been associated with chronic sleep deprivation, higher level of sleepiness and delayed melatonin peak secretion. Adolescents working or doing extracurricular occupations for more than 20 hours a week are more at risk for reduced sleep duration and sleepiness. Parental supervision about sleep during the weekdays were associated with more appropriate bedtime. Adolescents from low socio-demographic characteristics and from minority ethnic groups have reported displaying a shorter sleep duration. Finally, sleep disorders of a physiological origin such as narcolepsy, sleep apnea or restless legs syndrome, may explain the sleep deprivation and sleepiness. Sleep deprivation and sleepiness in adolescents have consequences on their health. Cognitive functioning, such as problem solving, attention or memory, as well as school performance, can be compromised by sleep deprivation and sleepiness. At the psychological level, adolescents reporting sleepiness are more prone to display mental health problems: associations were found between sleepiness and subjective perception of depression, anxiety, somatic complaints as well as with antisocial behaviors. Finally, 68 % of 16 year-old adolescents reported they drove a car, and the reported sleepiness could lead to road accidents due to reduced attentional functioning, reaction time and decision-making abilities. In the United-States, from 7 % to 16.5 % of deadly accidents were related to driving while drowsy. Highlighting etiology and problems associated with sleep deprivation and sleepiness in adolescents could guide researchers and clinicians towards the development of possible interventions. Public health measures and knowledge transfer programs regarding modifiable psychosocial and societal factors associated with sleep-wake bioregulation could increase awareness in parents as well as in political and societal decision makers.     

Genetic recombination as a major cause of mutagenesis in the human globin gene clusters

ObjectivesHomologous recombination is a frequent phenomenon in multigene families and as such it occurs several times in both the α- and β-like globin gene families. In numerous occasions, genetic recombination has been previously implicated as a major mechanism that drives mutagenesis in the human globin gene clusters, either in the form of unequal crossover or gene conversion. Unequal crossover results in the increase or decrease of the human globin gene copies, accompanied in the majority of cases with minor phenotypic consequences, while gene conversion contributes either to maintaining sequence homogeneity or generating sequence diversity. The role of genetic recombination, particularly gene conversion in the evolution of the human globin gene families has been discussed elsewhere.ConclusionHere, we summarize our current knowledge and review existing experimental evidence outlining the role of genetic recombination in the mutagenic process in the human globin gene families.