Extracorporeal Life Support Bridge to Ventricular Assist Device: The Double Bridge Strategy

In patients requiring left ventricular assist device (LVAD) support, it can be difficult to ascertain suitability for long‐term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support (ECLS) as a bridge‐to‐bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end‐organ dysfunction and reduce ventricular assist device (VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous‐flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty‐three patients required ECLS support pre‐LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end‐organ function pre‐VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end‐organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these “crash and burn” patients.     

Non‐Newtonian Blood Flow Simulation of Diastolic Phase in Bileaflet Mechanical Heart Valve Implanted in a Realistic Aortic Root Containing Coronary Arteries

Coronary arteries, which are branched from the sinuses, have tangible effects on the hemodynamic performance of the bileaflet mechanical heart valve (BMHV), especially in the diastolic phase. To better understand this issue, a computer model of ascending aorta including realistic sinus shapes and coronary arteries has been generated in this study in order to investigate the BMHV performance during diastole. Three‐dimensional transient numerical analysis is conducted to simulate the diastolic blood flow through the hinges and in coronary arteries under the assumption of non‐Newtonian behavior. Results indicate that as blood flows to the coronary arteries mainly during diastole, leakage flow from the hinge and other gaps will change considering the influence of coronary arteries. In addition, BMHV in the case of aortic replacement will increase blood flow rate into the coronary arteries about 100% as the mechanical valve resistance is higher than a native heart valve. Also, it will change the wall shear stress (WSS) distribution and increase coronary artery disease (CAD) potential. It is found out that although less leakage flow reduces the velocity magnitudes through the gaps, the shear stress acting on blood elements with non‐Newtonian assumption will be detrimental in the hinge corner at the ventricular side. High WSS of 1800 Pa is observed at beginning of diastole at this region.     

YAP and ERK mediated mechanical strain‐induced cell cycle progression through RhoA and cytoskeletal dynamics in rat growth plate chondrocytes

Yes‐associated protein (YAP) and extracellular signal‐regulated kinase (ERK) have been considered as key regulators in tissue homeostasis, organ development, and tumor formation. However, the roles of YAP and ERK in the mediating strain mechanosensing in the growth plate cartilage have not been determined. In this study, chondrocytes obtained from the growth plate cartilage of 2‐week‐old Sprague–Dawley rats were subjected to the mechanical strain with different magnitudes and durations at a frequency of 0.5 Hz. We found that YAP and ERK activation in response to mechanical strain was time and magnitude dependent. Pretreatment with a RhoA inhibitor (C3 toxin) or a microfilament cytoskeleton disrupting reagent (cytochalasin D) could suppress their activation. In addition, activated YAP and ERK were able to induce cell cycle progression by up‐regulating the expression of cell cycle‐related genes. These results shed new light on the function of YAP and ERK in mechanical strain‐promoted growth plate development. Our results also provided evidence that RhoA and cytoskeletal dynamics are required for this mechanotransduction. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1121–1129, 2016.     

脓毒症儿童的营养风险与营养支持研究进展

儿童脓毒症是危重病医学所面临的主要课题。有关研究表明,营养风险可能是间接影响脓毒症发生率及病死率的危险因素之一。通过营养风险筛查与评估,为评定脓毒症患儿是否具有营养风险、是否需要营养支持以及营养支持对患儿预后的影响提供参考依据。目前国内有关脓毒症儿童营养风险及营养支持的研究报道较少。本文主要对脓毒症儿童的营养风险与营养支持的研究进展作一综述。     

Fathers’ parenting self-efficacy during the transition to parenthood

Background: Little is known about the development of fathers’ parenting self-efficacy during the transition to parenthood.

Objectives: To analyse (1) fathers’ parenting self-efficacy developmental path and (2) the effects of anxious and depressive symptoms and coparenting support on fathers’ parenting self-efficacy developmental path, from the first trimester of pregnancy to 6 months postpartum.

Methods: Eighty-six fathers recruited at the first trimester of pregnancy completed self-report measures of anxious and depressive symptoms, coparenting support and parenting self-efficacy at the first and third trimesters of pregnancy, and at 1 and 6 months postpartum. Growth curve models were performed.

Results: An increase in fathers’ parenting self-efficacy was found from the first trimester of pregnancy to 6 months postpartum. The main effects of anxious symptoms and interaction effects of anxious symptoms and time were found on fathers’ parenting self-efficacy. Fathers with higher anxious symptoms revealed lower levels of parenting self-efficacy at the first trimester of pregnancy and a lower increase of parenting self-efficacy from this time to 6 months postpartum. The main effects of coparenting support were found in fathers’ parenting self-efficacy. At the first trimester of pregnancy, fathers who perceived more coparenting support revealed higher levels of parenting self-efficacy.

Conclusion: The present study may contribute to the literature by describing fathers’ parenting self-efficacy developmental path and the effects of anxious symptoms and coparenting support on fathers’ parenting self-efficacy developmental path during the transition to parenthood.     

A comparative study of dydrogesterone and micronized progesterone for luteal phase support during in vitro fertilization (IVF) cycles

The aim of the present study was to compare the efficacy, tolerability and patients’ satisfaction after the use of oral dydrogesterone with vaginal micronized progesterone for luteal-phase support (LPS) among infertile women undergoing in vitro fertilization (IVF). A total of 210 women (aged 20–40 years old) with a history of infertility, who underwent controlled ovarian stimulation for fresh intra-cytoplasmic sperm injection-embryo transfer cycles, were included in the study. Consequently, they were randomized to receive LPS with dydrogesterone 20?mg twice daily (n?=?96) or micronized progesterone 400?mg twice daily at the day of oocyte retrieval (n?=?114). The clinical success rate (31% versus 33%; p?=?0.888), miscarriage rate (5.0% versus 3.0%; p?=?0.721), ongoing pregnancy rate (30.0% versus 30.0%; p?=?1.000), implantation (22.0% versus 24.0%; p?=?0.254) and multiple pregnancy rate (5.30% versus 7.20%; p?=?0.394) were comparable among the two groups. Serum progesterone levels were significantly lower among the patients receiving dydrogesterone than the control group (13.62?±?13.83?ng/ml versus 20.66?±?18.09?ng/ml; p?=?0.001). However, there was no statistically significant difference regarding the patients’ satisfaction (p?=?0.825) and tolerability (0.790) between the two groups. Our results showed that oral dydrogesterone (40?mg/day) is as effective as vaginal micronized progesterone considering its clinical outcomes and patients’ satisfaction and tolerability, for LPS among women undergoing IVF.     

早产儿支气管肺发育不良防治环节中早期呼吸支持的策略

虽然呼吸窘迫综合征( RDS)仍然是导致极早和超早早产儿呼吸衰竭最常见疾病,但由于NICU呼吸技术的进步,其已经不再是死亡的主要病因。伴随着 RDS的发生,支气管肺发育不良( BPD)这一成熟依赖性肺疾病的发生和发展成为现代NICU防治的核心疾病之一。在早期呼吸支持策略环节中有以下共识与建议：(1)最大可能的使具有高风险RDS或RDS的极早和超早早产儿期避免气管插管,接受无创通气(nCPAP);(2)早期选择合适的方式接受肺表面活性物质(PS)治疗;(3)个体化的制定nCPAP或其他无创通气失败的标准,尽早接受PS救治和适宜的有创通气模式;(4)缩短通气时间,应用无创通气方式辅以咖啡因治疗降低拔管失败率。这些临床研究成果仍需要不断在实践中改进与完善,BPD的发生是多因素作用的结果,需要多维度的管理的进步才能真正实现有效的防治。