偏头痛与隐源性脑卒中患者卵圆孔未闭的声像图特征分析

目的 探讨存在卵圆孔未闭（PFO）的偏头痛和隐源性脑卒中（CS）患者经食管超声心动图和右心声学造影的声像图特征。方法 选取合并PFO的偏头痛患者162例（偏头痛组）、CS患者113例（CS组）,以经食管超声心动图观察PFO的形态、血流特点,以经食管右心声学造影观察PFO的造影特点及分流模式,比较2组间的差异。结果 偏头痛组与CS组间卵圆瓣长度、PFO入口和出口宽度、过隔血流所占比例、左心房内微气泡数量差异均无统计学意义（P均>0.05）。偏头痛组瓦氏动作时右心房内微气泡呈簇状通过PFO的比例（28/162,17.28%）明显小于CS组（36/113,31.86%）,差异有统计学意义（χ²=7.919,P=0.006）。偏头痛组患者平均年龄小于CS组,且以女性患者为多,而CS以男性患者居多,差异均有统计学意义（P均<0.001）。结论 偏头痛和CS患者的PFO形态学无明显差异。右心声学造影时,偏头痛和CS患者微气泡通过PFO进入左心房的模式存在差异,有望为临床预测CS提供新的指标。     

右心声学造影在不明原因短暂性脑缺血发作中的应用

目的 探讨右心声学造影在不明原因短暂性缺血发作（TIA）患者的应用价值。方法 收集我院收治的不明原因TIA患者120例（TIA组）及同期健康志愿者60名（正常组）。两组均接受右心声学造影观察是否存在卵圆孔未闭（PFO）。以左心室在3个心动周期出现来自右心房的微气泡信号≥5个诊断为卵圆孔未闭、右向左分流。结果 TIA组与正常组少量、中量右向左分流例数差异无统计学意义,大量右向左分流例数差异有统计学意义（P<0.01）。结论 右心声学造影能有效诊断PFO;PFO右向左分流量的大小与不明原因的TIA有关。     

胸椎正位片用于经外周置入中心静脉导管术后定位导管尖端

目的 评估胸椎X线正位片用于经外周置入中心静脉导管（PICC）术后定位导管尖端的价值。方法 回顾性分析114例接受PICC患者,术后接受1次以上胸部X线正位摄影、胸椎X线正位摄影及胸部CT,其中胸椎正位片183例次（A组）,胸部正位片334例次（B组）。对胸部CT纵隔窗图像进行重建联动轴位、冠状位、矢状位多平面重组,以多切面观察确定上腔静脉与右心房连接处（CAJ）位置及对应的轴位CT层面,确定CAJ位置,并于定位像上标记辅助线,测量并比较CAJ至右侧第6、7后肋、第6/7后肋间隙、气管隆嵴及心右缘上下段交界点的距离。结果 A组136例次（136/183,74.32%）导管尖端清楚显示,43例次（43/183,23.50%）隐约可见,4例次（4/183,2.19%）未显示;B组依次为131例次（131/334,39.22%）、169例次（169/334,50.60%）及34例次（34/334,10.18%）。A组导管尖端清楚显示率高于B组,未显示率低于B组（χ²=59.65,P<0.01）。CAJ至右侧第6后肋、右侧第6/7后肋间隙、右侧第7后肋、气管隆嵴及心右缘上下段交界点的距离分别为-1.95~7.51 cm、-2.82~6.44 cm、-3.91~5.00 cm、1.19~6.58 cm及-1.12~1.43 cm,平均（3.50±1.78）cm、（2.38±1.76）cm、（1.18±1.75）cm、（3.84±1.01）cm及（0.11±0.05）cm,总体差异有统计学意义（F=75.54,P<0.01）;两两比较,CAJ至右侧第6后肋距离与至气管隆嵴距离差异无统计学意义（P>0.05）,其余距离间差异均有统计学意义（P均<0.05）。CAJ与心右缘上下段交界点距离最短,以通过该交界点的水平线上垂直2 cm范围内为PICC导管尖端的理想位置。结论 胸椎正位片能清晰显示PICC导管尖端。心右缘上下段交界点水平线上垂直2 cm范围内为PICC导管尖端的理想位置。     

心源性休克患者静脉-动脉体外膜肺氧合脱机结局影响因素

目的 探讨心源性休克患者静脉-动脉体外膜肺氧合（V-A ECMO）脱机结局的影响因素。方法 回顾性观察37例接受V-A ECMO辅助心源性休克患者，根据是否耐受脱机试验分为可耐受组及不耐受组；再据最终是否成功脱机将可耐受组患者分为成功脱机亚组（脱机且30天内存活）及脱机失败亚组，比较2亚组患者相关资料，以及脱机试验过程中最低流量水平下2亚组超声测得血流动力学参数。结果 37例中，32例可耐受脱机试验（可耐受组），5例无法耐受（不耐受组）。可耐受组患者年龄（P=0.04）及ECMO辅助中出血率（P<0.01）均低于不耐受组，2组患者性别、原发疾病等差异均无统计学意义（P均>0.05）。可耐受组32例中，22例成功脱机，7例脱机失败，3例死亡。脱机试验中最低流量水平下，脱机成功亚组静脉血氧饱和度（SvO₂）、左心室流出道速度-时间积分（LVOT-VTI）、左心室射血分数（LVEF）及二尖瓣环侧壁收缩期运动速度（Sa）均高于脱机失败亚组（P均<0.05）。结论 SvO₂、LVOT-VTI、LVEF及Sa均为V-A ECMO辅助心源性休克患者脱机结局的影响因素。     

对比分析屏气三维梯度-自旋回波与呼吸门控触发三维快速自旋回波MR胰胆管成像

目的 对比屏气三维梯度-自旋回波MR胰胆管造影（3D-Grase-MRCP）与呼吸门控触发三维快速自旋回波MR胰胆管造影（3D-Tse-MRCP）图像质量。方法 对96例疑诊胰腺或胆道疾病患者行屏气3D-Grase-MRCP和呼吸门控触发3D-TSE-MRCP序列扫描，比较2种序列图像质量评分、显示病变情况及胆总管对比噪声比（CNR）。将3D-Grase-MRCP图像分为屏气组和屏气配合不佳组，对比2组图像质量评分。结果 3D-Tse-MRCP图像胆总管CNR值[357.08（209.73，594.38）]高于3D-Grase-MRCP[256.14（141.54，417.87），Z=-3.01，P<0.05]。3D-Grase-MRCP图像胆囊、胆囊管、胆总管及肝内胆管主要分支评分均高于3D-Tse-MRCP（P均<0.01），显示胆囊结石（n=42）和胆囊管结石（n=7）更清晰（P均<0.05）；屏气组（n=68）3D-Grase-MRCP图像胆囊、胆囊管、胆总管、胰管及肝内胆管主要分支质量评分均高于屏气配合不佳组（n=28，P均<0.01）。结论 屏气3D-Grase-MRCP图像质量及显示病变优于呼吸门控触发3D-Tse-MRCP，且扫描时间明显缩短。     

超声在急性呼吸窘迫综合征围静脉-静脉体外膜氧合期中的应用价值

目的探讨经胸超声心动图、血管超声及腹部超声在急性呼吸窘迫综合征(ARDS)患者围静脉-静脉体外膜氧合(V-V ECMO)期的临床应用价值。方法选取我院拟行V-V ECMO支持治疗的ARDS患者13例,分析超声在插管前对患者基本情况的评估结果,以及在插管过程中、V-V ECMO支持治疗期间和脱机后对心脏及血管相关并发症监测情况。结果行V-V ECMO支持治疗的13例ARDS患者中,12例存活至脱机,8例存活至康复出院。V-V ECMO插管过程中,7例在超声引导下调整套管末端位置;V-V ECMO支持治疗期间,2例在超声引导下调整套管末端位置。并发症发生情况:V-V ECMO支持治疗期间血管超声提示2例套管周围血栓形成,腹部超声提示1例腹腔出血;脱机后超声心动图提示1例下腔静脉附壁血栓形成,血管超声提示1例插管同侧下肢深静脉血栓形成。围V-V ECMO期无严重不良事件发生。结论超声在V-V ECMO插管过程中、支持治疗期间及监测并发症方面均具有重要价值。     

经颅多普勒发泡试验、经胸超声心动图右心造影及颈胸联合超声造影诊断卵圆孔未闭右向左分流

目的 对比观察经颅多普勒（TCD）发泡试验、经胸超声心动图（TTE）右心造影及颈胸联合超声造影诊断卵圆孔未闭（PFO）右向左分流（RLS）的价值。方法 对39例PFO-RLS患者先后行TCD发泡试验、TTE右心造影、颈胸联合超声造影和经食管超声心动图（TEE）检查,以TEE为金标准,观察前三者诊断PFO-RLS的能力。结果 TTE右心造影和颈胸联合超声造影诊断PFO-RLS的特异度均为100%,TTE右心造影的敏感度（53.49%）及准确率（54.85%）均低于TCD发泡试验（敏感度93.02%,准确率95.35%）和颈胸联合超声造影（敏感度90.69%,准确率95.23%）（P均<0.05）;TCD发泡试验与颈胸联合超声造影的诊断敏感度、准确率及检出不同分流量PFO-RLS能力差异均无统计学意义（P均>0.05）,且诊断一致性极高（Kappa=0.852）。TCD发泡试验和颈胸联合超声造影检出少量PFO-RLS的能力均高于TTE右心造影（P均<0.05）,与后二者诊断结果的一致性分别为中等和一般（Kappa=0.429、0.311）。结论 TCD发泡试验诊断PFO-RLS敏感度和准确率较高,但难以判断RLS位置;TTE右心造影诊断PFO-RLS特异度极高,但敏感度和准确率欠佳,尤其对少量PFO-RLS;颈胸联合超声造影有较高诊断特异度、敏感度和准确率,可检出少量PFO-RLS,并有助于判断RLS位置。     

定量型声辐射力脉冲弹性成像评价慢性心力衰竭患者肝脏弹性

目的 探讨定量型声辐射力脉冲弹性成像（ARFI）评估慢性心力衰竭（简称心衰）患者肝脏弹性的应用价值。方法 对30例左心衰患者（左心衰组）、30例右心衰患者（右心衰组）及30名健康志愿者（对照组）行常规超声检查及血液生化指标检测,并以定量型ARFI检测肝脏杨氏模量值。分析慢性心衰患者肝脏杨氏模量值与生化指标、下腔静脉内径、肝静脉内径及肝右叶最大斜径的相关性。结果 左心衰组、右心衰组肝脏杨氏模量值均高于对照组（P均<0.05）,且右心衰组高于左心衰组（P<0.05）。心衰患者肝脏杨氏模量值与脑钠肽、总胆红素、γ-谷氨酰基转移酶、碱性磷酸酶、下腔静脉内径、肝左静脉内径、肝中静脉内径及肝右静脉内径均呈正相关（r=0.325、0.382、0.355、0.379、0.451、0.445、0.395、0.645,P均<0.05）,与左心室射血分数、肝右叶最大斜径无明显相关（P均>0.05）。结论 定量型ARFI可用于评估慢性心衰患者肝脏弹性,且肝脏弹性与心衰严重程度相关。     

能谱CT定量参数鉴别诊断原发性胃淋巴瘤和胃癌

目的 探讨能谱CT（GSI）定量参数鉴别诊断原发性胃淋巴瘤（PGL）和胃癌（GC）的价值。方法 收集PGL患者16例（PGL组）、GC患者24例（GC组）,行平扫和GSI双期增强扫描。测量两组肿瘤病灶的单能量CT值、碘（水）基物质浓度和有效原子序数（Z_eff）,计算标化碘浓度（NIC）、能谱曲线斜率（λ_HU）、标化原子序数（Z_eff-c）。采用独立样本t检验对各定量参数进行比较分析,运用ROC曲线评估其诊断效能。结果 PGL组增强双期40~90 keV图像λ_HU均低于GC组（t=2.90、3.69,P=0.008、0.001）。PGL组动脉期40 keV、静脉期40~120 keV单能量CT值均低于GC组（P均<0.05）;PGL组70 keV增强双期NIC、动脉期标化水浓度均低于GC组,PGL组静脉期Z_eff-c高于GC组（P均<0.05）;静脉期70 keV单能量图像以λ_HU=2.63 mg/cm³为阈值鉴别诊断PGL和PC的敏感度和特异度分别为62.5%和100%。结论 GSI定量参数对PGL和GC的鉴别诊断有一定实用价值。     

不同类型冠心病患者股动脉斑块超声特征

目的 探讨股动脉斑块声像特征诊断非ST段抬高型急性冠状动脉综合征（NSTE-ACS）的价值。方法 选取冠心病伴颈动脉及股动脉斑块患者72例,分为NSTE-ACS组（n=42）和慢性心肌缺血综合征（CIS）组（n=30）,行CEUS、三维超声及灰阶强度定量分析,检测斑块造影增强强度（EI）、斑块体积、形态特征及回声灰阶强度（EL）等参数并进行对比分析。结果 NSTE-ACS组斑块EI、形态不规则斑块比例高于CIS组,EL低于CIS组（P均<0.05）。颈动脉和股动脉斑块EI、EL和形态分类均与NSTE-ACS具有相关性（P均< 0.05）。股动脉斑块EI、EL为NSTE-ACS的危险因素（OR=1.222、1.177,P<0.05）。颈动脉斑块EI、EL诊断NSTE-ACS的曲线下面积（AUC）分别为0.801、0.757（P均< 0.001）,股动脉斑块EI、EL的AUC分别为0.814、0.774（P均< 0.001）。结论 股动脉斑块内新生血管、形态特征和内部回声均与NSTE-ACS存在相关性,且较颈动脉更强;多种超声技术联合评价股动脉斑块声像图特征有望成为预测冠状动脉斑块稳定性、筛查冠心病高危患者的参考指标。     

Superior vena cava drainage improves upper body oxygenation during veno-arterial extracorporeal membrane oxygenation in sheep

IntroductionDifferential hypoxia is a pivotal problem in patients with femoral veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) support. Despite recognition of differential hypoxia and attempts to deliver more oxygenated blood to the upper body, the mechanism of differential hypoxia as well as prevention strategies have not been well investigated.MethodsWe used a sheep model of acute respiratory failure that was supported with femoral VA ECMO from the inferior vena cava to the femoral artery (IVC-FA), ECMO from the superior vena cava to the FA (SVC-FA), ECMO from the IVC to the carotid artery (IVC-CA) and ECMO with an additional return cannula to the internal jugular vein based on the femoral VA ECMO (FA-IJV). Angiography and blood gas analyses were performed.ResultsWith IVC-FA, blood oxygen saturation (SO₂) of the IVC (83.6 ± 0.8%) was higher than that of the SVC (40.3 ± 1.0%). Oxygen-rich blood was drained back to the ECMO circuit and poorly oxygenated blood in the SVC entered the right atrium (RA). SVC-FA achieved oxygen-rich blood return from the IVC to the RA without shifting the arterial cannulation. Subsequently, SO₂ of the SVC and the pulmonary artery increased (70.4 ± 1.0% and 73.4 ± 1.1%, respectively). Compared with IVC-FA, a lesser difference in venous oxygen return and attenuated differential hypoxia were observed with IVC-CA and FA-IJV.ConclusionsDifferential venous oxygen return is a key factor in the etiology of differential hypoxia in VA ECMO. With knowledge of this mechanism, we can apply better cannula configurations in clinical practice.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-015-0791-2) contains supplementary material, which is available to authorized users.     

超声心动图评价肺动脉高压大鼠右心结构和功能的动态变化

目的 通过超声心动图无创性定量评价肺动脉高压大鼠右心结构和功能的变化,探讨早期评价右心功能的指标。方法 选取SD大鼠40只,随机分为5组,每组8只,分别标记为对照组和实验组(3周、4周、5周、6周亚组),对实验组大鼠腹部皮下注射野百合碱,分别于给药后3周、4周、5周、6周进行超声心动图检查,再进行右心导管测压。采用ECHOPAC工作站脱机分析,测量超声心动图数据,比较各组数据的差异。结果 实验组较对照组肺动脉压力升高,差异有统计学意义(P均<0.05)。4周亚组右心室中间段内径、右心室面积变化率、右心室侧壁厚度、偏心指数、肺动脉瓣加速时间与射血时间比值以及5周亚组三尖瓣瓣环位移、右心房横径、右心房长径、右心房面积与对照组相比,差异有统计学意义(P均<0.05)。结论 右心室中间段内径、右心室面积变化率、右心室侧壁厚度,偏心指数、肺动脉瓣加速时间与射血时间比值能较早反映大鼠肺动脉压力升高时右心室结构及功能的改变。     

Anesthesia and perioperative management for giant adrenal Ewing’s sarcoma with inferior vena cava and right atrium tumor thrombus: A case report

BACKGROUNDEwing’s sarcoma of the adrenal gland with inferior vena cava (IVC) and right atrium thrombus is extremely rare. Here, we report a case of giant adrenal Ewing’s sarcoma with IVC and right atrium tumor thrombus and summarize the anesthesia and perioperative management.CASE SUMMARYA young female was admitted to the Department of Urology with intermittent pain under the right costal arch for four months. Enhanced abdominal computed tomography revealed a large retroperitoneal mass (22 cm in diameter), which may have originated from the right adrenal gland and was closely related to the liver. Transthoracic echocardiography showed a strong echogenic filling measuring 70 mm extended from the IVC into the right atrium and ventricle. After preoperative preparation with cardiopulmonary bypass, sufficient blood products, transesophageal echocardiography and multiple monitoring, tumor and thrombus resection by IVC exploration and right atriotomy were successfully performed by a multidisciplinary team. Intraoperative hemodynamic stability was the major concern of anesthesiologists and the status of tumor thrombus and pulmonary embolism were monitored continuously. During transfer of the patient to the intensive care unit (ICU), cardiac arrest occurred without external stimulus. Cardiopulmonary resuscitation was performed immediately and cardiac function was restored after 1 min. In the ICU, extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT) were provided to maintain cardiac, liver and kidney function. Histopathologic examination confirmed the diagnosis of Ewing’s sarcoma. After postoperative treatments and rehabilitation, the patient was discharged from the urology ward.CONCLUSIONAn adrenal Ewing’s sarcoma with IVC and right atrium thrombus is extremely rare, and its anesthesia and perioperative management have not been reported. Thus, this report provides significant insights in the perioperative management of patients with adrenal Ewing’s sarcoma and IVC tumor thrombus. Intraoperative circulation fluctuations and sudden cardiovascular events are the major challenges during surgery. In addition, postoperative treatments including ECMO and CRRT provide essential support in critically ill patients. Moreover, this case report also highlights the importance of multidisciplinary cooperation during treatment of the disease.     

Disrupting differential hypoxia in peripheral veno-arterial extracorporeal membrane oxygenation

Patients receiving circulatory support with peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) are at risk of developing differential hypoxia. This phenomenon occurs in patients with concomitant respiratory failure. Poorly oxygenated blood, ejected into the ascending aorta from the left ventricle, competes with retrograde flow from the ECMO circuit, potentially causing myocardial and cerebral ischaemia. In a recent Critical Care article, Hou et al. use an animal model of peripheral VA-ECMO to study the physiology of differential hypoxia. Their findings support a dual circuit hypothesis, and show how different cannulation strategies can disrupt the two circuits. In particular, strategies that increase venous oxygen saturations in the pulmonary artery can have a large effect on oxygenation saturation in the ascending aorta. The authors provide evidence supporting the use of veno-arterial-venous ECMO in patients who require peripheral VA-ECMO but have simultaneous respiratory failure.Using peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) for circulatory support, in patients with concomitant respiratory failure, may cause differential hypoxia [1]. Differential hypoxia occurs because patients receiving peripheral VA-ECMO are dependent on retrograde flow, classically from a femoral artery cannula, to deliver oxygenated blood to the upper body. In patients with respiratory failure, however, the left ventricle will eject poorly oxygenated blood into the ascending aorta, which increasingly competes with retrograde flow from the ECMO circuit as cardiac function recovers. If cardiac function is sufficient, poorly oxygenated blood may be preferentially delivered to the myocardium and brain, risking hypoxic injury [2]. Whilst the clinical significance of this phenomenon is not well described, most physicians monitor for differential hypoxia and choose alternative cannulation strategies when it occurs [3].Differential hypoxia is one of the many reasons why peripheral VA-ECMO should be avoided in patients receiving ECMO for respiratory failure [4], and is also why we should measure arterial haemoglobin oxygen saturation (SO₂) in both hands of patients receiving peripheral VA-ECMO. Lower saturation readings in the right hand, compared with the left, indicate that this phenomenon is developing. Understanding the physiology of differential hypoxia, and its clinical implications, is important, not least because ECMO use is increasing. According to the Extracorporeal Life Support Organisation (ELSO) January 2015 summary, the reported number of patients receiving ECMO for respiratory failure has more than tripled since 2009, and nearly 15 % of these received some form of VA-ECMO [5].In a recent Critical Care article, Hou et al. [6] added to our understanding of differential hypoxia physiology. By applying peripheral VA-ECMO to an animal model of respiratory failure, with normal cardiac function, Hou et al. created differential hypoxia. Their findings support a dual circuit hypothesis, which magnifies the degree of differential hypoxia. A dual circuit is established when the upper body receives poorly oxygenated blood from the failing native lungs, via the left ventricle, and the lower body receives oxygenated blood from the ECMO circuit. The two circuits are independently sustained because poorly oxygenated blood from the left ventricle supplies only the upper body, drains into the superior vena cava (SVC), and then returns to the left ventricle without being adequately oxygenated. The blood then recycles through the upper body, creating an upper body circuit in which SVC blood is severely deoxygenated. Simultaneously, oxygenated blood from the ECMO circuit perfuses only the lower body and drains into the inferior vena cava (IVC), resulting in a relatively high IVC SO₂. A separate, well-oxygenated, lower body circuit is maintained because IVC blood returns to the ECMO circuit, via the IVC drainage cannula, and has no opportunity to mix with severely deoxygenated blood from the SVC. The findings of Hou et al. support a dual circuit hypothesis for two reasons. Firstly, contrast introduced into the ECMO circuit does not travel above the level of the diaphragm in the descending aorta, demonstrating that retrograde flow from the ECMO circuit supplies only the lower body. Secondly, they confirm that the two circuits do not mix in the venous circulation, because SO2 in the SVC, pulmonary artery, and ascending aorta is equally poor at 33–40 %, whilst in the IVC it is 84 %.An important observation in this study was disruption of the two circuits by advancing the IVC cannula into the SVC. As a consequence of this manoeuvre, poorly oxygenated SVC blood preferentially drained into the ECMO circuit, and well-oxygenated venous blood from the IVC returned to the right heart, ultimately reaching the ascending aorta. In Hou et al.’s model, this simple manoeuvre increased SO₂ in the ascending aorta from 34 to 75 %. Aortic SO₂ in this range may be sufficient [7]; lower levels are commonly tolerated in climbers, albeit with a long adaptation time [8], and in veno-venous ECMO (VV-ECMO) it is common to target arterial SO₂ ≧80 %, with no obvious detrimental affects [4]. The authors also show that an additional return cannula, delivering oxygenated blood directly to the internal carotid artery or SVC, further improved SO₂ in the ascending aorta.As always, we need to be cautious translating animal findings directly into clinical practice. Firstly, these animals had normal cardiac function at the start of the study. In clinical practice we would not consider VA-ECMO in a patient with normal cardiac function, and normal cardiac function undoubtedly exaggerated differential hypoxia in Hou et al.’s animal model. Whilst this makes the physiology easier to study, it may also exaggerate the potential benefits of modifying cannulation strategies. Secondly, although carotid cannulation has been commonly used in paediatric ECMO, the potential neurological sequelae could be considerable in adults with existing carotid artery disease. Finally, the safety of advancing a cannula from the IVC to the SVC is not established, although modern double lumen catheters, advanced from the SVC to the IVC, are in clinical use with VV-ECMO [9].Despite these concerns, the findings from this animal study can still be applied to clinical practice. Demonstrating improved SO₂ in the ascending aorta, simply by adding an additional cannula returning oxygenated blood to the SVC, supports the use of veno-arterial-venous ECMO (VAV-ECMO) in patients who require VA-ECMO but have concomitant respiratory failure. VAV-ECMO describes an ECMO cannulation strategy where oxygenated blood is returned to both the arterial system and the venous system, typically via the femoral artery and the SVC (right internal jugular vein cannula), respectively [10].In conclusion, Hou et al. have elegantly demonstrated that a dual circuit mechanism may be responsible for sustaining differential hypoxia in patients receiving peripheral VA-ECMO. They have also shown that simply draining blood from the SVC, or returning oxygenated blood to the SVC and proximal arterial circulation, disrupts the two circuits and delivers adequately oxygenated blood into the ascending aorta. Therefore, when faced with a patient requiring mechanical circulatory support, who also has severe respiratory failure, VAV-ECMO would seem a logical approach—certainly based on the animal model presented by Hou et al.     

One hundred ECMO retrivals before and during the Covid-19 pandemic: an observational study

ObjectivesPatients with severe acute respiratory distress syndrome may require veno-venous extracorporeal membrane oxygenation (V-V ECMO) support. For patients in peripheral hospitals, retrieval by mobile ECMO teams and transport to high-volume centers is associated with improved outcomes, including the recent COVID-19 pandemic. To enable a safe transport of patients, a specialised ECMO-retrieval program needs to be implemented. However, there is insufficient evidence on how to safely and efficiently perform ECMO retrievals. We report single-centre data from out-of-centre initiations of VV-ECMO before and during the COVID-19 pandemic.Design & settingSingle-centre retrospective study. We include all the retrievals performed by our ECMO centre between January 1st, 2014, and April 30th, 2021.ResultsOne hundred ECMO missions were performed in the study period, for a median retrieval volume of 13 (IQR: 9–16) missions per year. the cause of the acute respiratory distress syndrome was COVID-19 in 10 patients (10 %). 98 (98 %) patients were retrieved and transported to our ECMO centre. To allow safe transport, 91 of them were cannulated on-site and transported on V-V ECMO. The remaining seven patients were centralised without ECMO, but they were all connected to V-V ECMO in the first 24 hours. No complications occurred during patient transport. The median duration of the ECMO mission was 7 hours (IQR: 6–9, range: 2 – 17). Median duration of ECMO support was 14 days (IQR: 9–24), whereas the ICU stay was 24 days (IQR:18–44). Overall, 73 patients were alive at hospital discharge (74 %). Survival rate was similar in non-COVID-19 and COVID-19 group (73 % vs 80 %, p = 0.549).ConclusionIn this single-centre experience, before and during COVID-19 era, retrieval and ground transportation of ECMO patients was feasible and was not associated with complications. Key factors of an ECMO retrieval program include a careful selection of the transport ambulance, training of a dedicated ECMO mobile team and preparation of specific checklists and standard operating procedures.     

实时三维超声心动图评估射血分数减低的左心力衰竭患者的右心室重构

目的 采用单心动周期实时三维超声心动图(sRT-3DE)结合传统二维超声心动图探讨左心室射血分数(LVEF)减低的左心力衰竭患者肺高压(PH)对右心室重构的影响。方法 对sRT-3DE检查LVEF<50%的60例患者(病例组)根据肺动脉收缩压(PASP)及肺血管阻力(PVR)不同分为3个亚组:HF-NPH亚组15例,HF-PPH亚组15例,HF-RPH亚组30例,正常健康人35名为对照组。对两组行常规二维超声及sRT-3DE检查,分析获得三维、二维及多普勒超声参数,进行组间对比分析和相关性分析。结果 与对照组比较:病例组右心室舒张末期容积指数(EDVI)、收缩末期容积指数(ESVI)、基底部横径(D1)、长径(LD)、D1/中间横部径(D2)、射血分数(EF)减小。与HF-NPH亚组比较,HF-PPH亚组右心室ESVI、D1/D2、LD/D2增大。与HF-PPH亚组比较,HF-RPH亚组右心室EDVI、ESVI、D2增大,右心室EF、LD/D2减低。PVR与PASP、右心室EF与左心室EF、右心室LD与左心室LD呈正相关性(r=0.765、0.628、0.725;P均<0.01),PVR与右心室EF呈负相关(r=-0.715,P<0.01),且高于与PASP的相关性(r=-0.623,P<0.01)。结论 sRT-3DE结合传统二维及多普勒超声可准确评估左心力衰竭患者的右心室重构,有助于判断右心室结构和功能状态。     

CT IVC venogram: normalized quantitative criteria for patency and thrombosis

Purpose

Establish normal attenuation ratios for vein to artery on CT IVC venogram and determine a vascular attenuation ratio diagnostic of thrombus.

Methods

This retrospective, HIPAA-compliant study included 56 CT IVC venograms. Images were reviewed for the presence of femoral vein or IVC thrombus. Attenuation ratios for each vein and its corresponding artery were calculated by two observers and averaged in four venous stations (right and left femoral veins, and IVC at the confluence of the iliac veins and at the left renal vein). The reference standard for the absence of thrombus was clinical follow-up and for the presence of thrombus it was thrombectomy or catheter venogram. Receiver operating characteristic (ROC) analysis was performed using ratios from one venous station and threshold for thrombus was determined using the Youden’s index.

Results

36 of 56 CTs demonstrated no thrombus. 20 CTs demonstrated thrombus, confirmed in eight patients. For CTs with no thrombus, median ratios among the venous stations ranged from 0.89 (IQR 0.83–0.93) to 0.91 (IQR 0.86–0.94). ROC analysis of ratios from a single representative station (left femoral vein, n = 4 confirmed clots) demonstrated an area under the curve (AUC) of 0.994 (p = 0.001) and a threshold of 0.67 for diagnosing thrombus [sensitivity 100% (95% CI 39.76–100%), specificity 97.5% (86.84–99.94%)].

Conclusion

The normal attenuation ratio of vein to artery in the absence of venous thrombus on a 3-min delay CT IVC venogram is approximately 0.91. A ratio less than 0.67 is highly suggestive of thrombus.

     

Central venous pressure,global end-diastolic index,and the inferior vena cava collapsibility/distensibility indices to estimate intravascular volume status in critically ill children: A pilot study

BackgroundThe assessment of the volume status in critically ill paediatric patients in intensive care units is vitally important for fluid therapy management. The most commonly used parameter for detecting volume status is still central venous pressure (CVP); however, in recent years, various kinds of methods and devices are being used for volume assessment in intensive care units.ObjectivesWe aimed to evaluate the relationship between CVP, the global end-diastolic index (GEDI), and ultrasound measurements of the collapsibility and distensibility indices of the inferior vena cava (IVC) in paediatric patients undergoing Pulse index Contour Cardiac Output (PiCCO) monitoring.MethodsFifteen patients receiving PiCCO monitoring were prospectively included in the study. Forty-nine PiCCO measurements were evaluated, and simultaneous CVP values were noted. After each measurement, IVC collapsibility (in spontaneously breathing patients) and distensibility (in mechanically ventilated patients) indices were measured with bedside ultrasound.ResultsThe mean age was 93.2 ± 61.3 months. Significant and negative correlations of the GEDI were found with the IVC collapsibility index (in spontaneously breathing patients) and the IVC distensibility index (in mechanically ventilated patients) (r = ?0.502, p < 0.001; r = ?0.522, p = 0.001, respectively). A significant and weakly positive correlation was found between the GEDI and CVP (r = 0.346, p = 0.015), and a significant and negative correlation was found between the IVC collapsibility index and CVP (r = ?0.482, p = 0.03). The correlation between the IVC distensibility index and CVP was significant and negative (r = ?0.412, p = 0.04).ConclusionThe use of PiCCO as an advanced haemodynamic monitoring method and the use of bedside ultrasound as a noninvasive method are useful to evaluate the volume status in critically ill paediatric patients in intensive care. These methods will gradually come to the fore in paediatric intensive care.