Intrapartum fetal surveillance: a physiological approach

Continuous utero-placental circulation, and patent umbilical blood vessels ensure an uninterrupted transfer of oxygen and nutrients to the fetus as well as clearance of metabolic waste products. The onset of labour characterized by progressive and strong uterine contractions poses a threat to fetal oxygenation as a result of collapsing the spiral arterioles traversing the myometrium to supply the placental bed, and repetitive compression of the blood vessels within the umbilical cord. Human fetuses are equipped with compensatory mechanisms to cope with transient interruptions of blood supply during labour. The ability to compensate may be blunted in cases of poor fetal reserves, increased metabolic demand (macrosomia or maternal fever), and due to non-hypoxic pathways (e.g. chorioamniontis or fetal hypovolumia-hypotension syndrome). Intrapartum fetal surveillance involves prompt recognition of the features that signal the onset of fetal decompensation on the cardiotocograph (CTG) to ensure a timely intervention to avoid hypoxic-ischaemic encephalopathy (HIE) or perinatal deaths. This article summarises a ‘physiological approach’ to the interpretation of the CTG which, in places, conflicts with other current UK guidance.     

Delineating the geographic context of physical activities: A systematic search and scoping review of the methodological approaches used in social ecological research over two decades

BackgroundThe social ecological approach suggests that the spatial context among other factors influence physical activity behavior. Ample research documents physical environmental effects on physical activity. Yet, to date inconsistent associations remain, which might be explained by conceptual and methodological challenges in measuring the spatial dimensions of health behavior. We review methods applied to measure the spatial contexts in the social ecological physical activity literature.MethodsOnline databases and selected reviews were used to identify papers published between 1990 and 2020. A total of 2167 records were retrieved, from which 412 studies that used physical activity as a primary outcome variable, included measures of the physical environment and applied the main principles of the social ecological approach, were included.ResultsSubjective approaches were the dominant method to capture the spatial context of physical activities. These approaches were applied in 67% (n=279) of the studies. From the objective approaches an administrative unit was most prevalent and was applied in 29% (n=118) of the studies. The most comprehensive objective spatial methods that capture the true environmental exposure, were used only in 2% (n=10) of the studies.ConclusionsCurrent social ecological physical activity research applies simple conceptualizations and methods of the spatial context. While conceptual and methodological concerns have been repeatedly expressed, no substantive progress has been made in the use of spatial approaches. To further our understanding on place effects on health, future studies should carefully consider the choice of spatial approaches, and their effect on study results.     

长臂单轴椎弓根螺钉在单纯性胸腰椎压缩性骨折复位固定中的应用及对肌肉损伤的影响

目的分析长臂单轴椎弓根螺钉经 Wiltse入路在单纯性胸腰椎压缩性骨折中的应用效果及对肌肉损伤的影响。方法选取自 2018年 1月至 2020年 8月周口市中心医院收治的单纯性胸腰椎压缩性骨折病人 87例，根据复位固定术式不同，分为观察组 38例、对照组 49例，其中观察组采取长臂单轴椎弓根螺钉经 Wiltse入路，对照组采取 AF系统经传统后正中入路。记录两组病人围术期指标、手术前后血清肌肉损伤指标［肌酸激酶( CK)、肌红蛋白( Mb)］变化；采用疼痛视觉模拟评分( VAS)评价病人不同时间节点疼痛水平；经胸腰椎正侧位片检查获取伤椎原始高度( H0)、术前及术后 1周伤椎椎体前缘高度( H1H2)，计算术前、术后 1周伤椎相对高度( H1/H0、H2/H0)及伤椎复位率，并测量矢状位 Cobb角变化；随访 3个月，采用 Oswestry功能障、碍指数( ODI)评价功能障碍情况，并统计手术相关并发症。结果观察组手术时长、术中失血量、术后引流量及首次下床活动时间均明显短于或低于对照组( P<0.05)。术后 3d，两组血清 CK、Mb水平均较术前升高( P<0.05)，且观察组血清 CK、Mb水平     

Method’s corner: Allergist’s guide to network meta-analysis

Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care.     

Retroperitoneal-first laparoscopic approach (Retlap)-assisted distal pancreatectomy with celiac axis resection (DP-CAR): A novel minimally invasive approach for achieving adequate dorsal surgical margin

BackgroundDistal pancreatectomy with celiac axis resection (DP-CAR) is a procedure to secure a surgical margin for a locally advanced pancreatic body cancer that invades the celiac axis. However, in patients with cancer close to the root of the celiac axis, obtaining adequate surgical margins can be difficult because the tumor obstructs the field of vision to the root of the celiac axis. Previously, we described the retroperitoneal-first laparoscopic approach (Retlap) to achieve both accurate evaluation of resectability for locally advanced pancreatic cancer requiring DP-CAR [1] and adequate surgical margin for laparoscopic distal pancreatectomy [2]. In this video, we introduce Retlap-assisted DP-CAR as a minimally invasive approach for performing an artery-first pancreatectomy [3, 4] and achieving sufficient dorsal surgical margin (Fig. 1).MethodsOur patient is a 67-year-old man with a 55 × 29-mm pancreatic body tumor after chemotherapy. Preoperative computed tomography revealed a tumor close to the root of the celiac axis. Because the area of tumor invasion on preoperative images was near the root of the celiac artery, Retlap-assisted DP-CAR was performed to determine whether the celiac axis can be secured and obtain an adequate dorsal surgical margin (Fig. 2).ResultsThe operative time and estimated blood loss was 715 min and 449 mL, respectively. In spite of the advanced tumor's location and size, R0 resection was achieved in a minimally invasive way.ConclusionRetlap-assisted DP-CAR is not only technically feasible and useful for achieving accurate evaluation of resectability but also facilitates obtaining an adequate surgical margin.     

Cranio-caudal approach to hepatic veins in laparoscopic central bisectionectomy (with Video)

BackgroundLaparoscopic central bisectionectomy (Couinaud's segment IV, V, and VIII) needs exposure of the RHV and MHV on the surface of the remnant and the resecting side, respectively. Avoiding venous injury is mandatory and laparoscopy-specific cranio-caudal approach to hepatic veins might be helpful [1]. We present this procedure in performing laparoscopic central bisectionectomy.PatientA 45-year-old female was admitted to our hospital with a 6 cm HCC in the segment VIII and IV. Her comorbid disease was non-cirrhotic HBV hepatitis (Child-Pugh grade A) and diabetes (untreated).MethodAfter cholecystectomy, G₄ branches were dissected and cut by extra- or intra-hepatic approach. Hilar plate was dissected and the G_ant was encircled and occluded by a vascular clip. Afterwards, exposure of the MHV was started at its root on IVC [2,3] and extended in cranio-caudal direction [1]. After sufficient space was obtained around the G_ant, the G_ant and the MHV were cut. Parenchymal transection between right anterior and right posterior sections was also started form the root of the RHV to its cranio-caudal direction. Liver resection was finished with full exposure of the RHV.ResultsThe operating time was 380 minutes, and the blood loss volume was 30 ml. Postoperative CT image showed exposure of the RHV and umbilical portion of Glissonean branch, and no fluid retention.ConclusionLaparoscopy-specific cranio-caudal approach to hepatic veins may be useful to avoid split injury of venous branches [4], especially if the hepatectomy requires complete exposure of hepatic vein, such as central bisectionectomy.