Inferior vena cava collapsibility loses correlation with internal jugular vein collapsibility during increased thoracic or intra-abdominal pressure

Purpose

Point-of-care ultrasound evaluates inferior vena cava (IVC) and internal jugular vein (IJV) measurements to estimate intravascular volume status. The reliability of the IVC and IJV collapsibility index during increased thoracic or intra-abdominal pressure remains unclear.

Methods

Three phases of sonographic scanning were performed: spontaneous breathing phase, increased thoracic pressure phase via positive pressure ventilation (PPV) phase, and increased intra-abdominal pressure (IAP) phase via laparoscopic insufflation to 15 mmHg. IVC measurements were done at 1–2 cm below the diaphragm and IJV measurements were done at the level of the cricoid cartilage during a complete respiratory cycle. Collapsibility index was calculated by (max diameter − min diameter)/max diameter × 100 %. Chi square, t test, correlation procedure (CORR) and Fisher’s exact analyses were completed.

Results

A total of 144 scans of the IVC and IJV were completed in 16 patients who underwent laparoscopic surgery. Mean age was 46 ± 15 years, with 75 % female and 69 % African-American. IVC and IJV collapsibility correlated in the setting of spontaneous breathing (r² = 0.86, p < 0.01). IVC collapsibility had no correlation with the IJV in the setting of PPV (r² = 0.21, p = 0.52) or IAP (r² = 0.26, p = 0.42). Maximal IVC diameter was significantly smaller during increased IAP (16.5 mm ± 4.9) compared to spontaneous breathing (20.6 mm ± 4.8, p = 0.04) and PPV (21.8 mm ± 5.6, p = 0.01).

Conclusion

IJV and IVC collapsibility correlated during spontaneous breathing but there was no statistically significant correlation during increased thoracic or intra-abdominal pressure. Increased intra-abdominal pressure was associated with a significant smaller maximal IVC diameter and cautions the reliability of IVC diameter in clinical settings that are associated with intra-abdominal hypertension or abdominal compartment syndrome.     

Resolution of brainstem edema after treatment of a dural tentorial arteriovenous fistula

We report a patient with a petrosal arterio-venous dural fistula draining into the ponto-mesencephalic and medullary venous systems presenting with edema of the brain stem and complete reversal of magnetic resonance imaging (MRI) abnormalities after combined endovascular and surgical treatments. The venous anatomy of the posterior fossa and the significance of the venous involvement as the cause of clinical symptoms and imaging abnormalities in cerebro-medullary vascular lesions are discussed.     

Neural underpinnings of superior action prediction abilities in soccer players

The ability to form anticipatory representations of ongoing actions is crucial for effective interactions in dynamic environments. In sports, elite athletes exhibit greater ability than novices in predicting other players’ actions, mainly based on reading their body kinematics. This superior perceptual ability has been associated with a modulation of visual and motor areas by visual and motor expertise. Here, we investigated the causative role of visual and motor action representations in experts’ ability to predict the outcome of soccer actions. We asked expert soccer players (outfield players and goalkeepers) and novices to predict the direction of the ball after perceiving the initial phases of penalty kicks that contained or not incongruent body kinematics. During the task, we applied repetitive transcranial magnetic stimulation (rTMS) over the superior temporal sulcus (STS) and the dorsal premotor cortex (PMd). Results showed that STS-rTMS disrupted performance in both experts and novices, especially in those with greater visual expertise (i.e. goalkeepers). Conversely, PMd-rTMS impaired performance only in expert players (i.e. outfield players and goalkeepers), who exhibit strong motor expertise into facing domain-specific actions in soccer games. These results provide causative evidence of the complimentary functional role of visual and motor action representations in experts’ action prediction.     

产后上矢状窦血栓形成12例报告及其预防措施的探讨

目的：探讨产后上矢状窦血栓形成的发病机制、诱发因素及预防发病的措施。方法：回顾12例产后上矢状窦血栓形成患者临床资料，特别是围产期并发症、合并症、分娩方式及产后生活起居等，分析诸因素与上矢状窦血栓形成的可能关系。结果：产褥期凝血机能增强，并发妊娠高血压综合征，产时、产后失血过多，产后多汗、不正确发汗，产后卧床较久、饮水不足、高脂饮食，产褥感染及剖宫产等是产后上矢状窦血栓形成的诱发因素。结论：注意围产期相关并发症、合并症的防治、严格剖宫产指征，避免盲目剖宫产及普及产褥期卫生知识，避免产后卧床较久、合理饮食，可减少产后上矢状窦血栓形成的发生。     

A case report of an intracaval extrathoracic solitary fibrous tumour

Solitary fibrous tumours are infrequent neoplasms based in the pleura that are predominantly benign with malignant pathology and behaviour described in 10–36% of cases. Extrathoracic solitary fibrous tumours (ESFTs) have been considered separately to their intrathoracic counterparts and comprise a third of all solitary fibrous tumours. The extrathoracic location was identified as an adverse prognostic factor for local recurrence but not for metastatic disease. So far, there have not been any reports of solitary fibrous tumours demonstrating caval infiltration. We present a case of a benign ESFT infiltrating into the perirenal inferior vena cava. Together with extrauterine leiomyomas, ESFTs should also be considered as a differential diagnosis for the rare benign lesions invading the inferior vena cava.     

When an unidentified foreign object appears in the inferior vena cava: recognizing the presence of TIPS stent on transthoracic echocardiographic imaging

We describe the case of 65-year-old female with a history of hypertension, diabetes, and cirrhosis. In the subcostal view on a routine transthoracic echocardiogram (TTE), she is found to have an unidentified round prosthetic appearing object in the inferior vena cava (IVC). Upon further investigation, the object was identified as a transjugular intrahepatic portosystemic shunt (TIPS) stent, which was seen in cross section in a hepatic vein draining into the IVC. Most echocardiographers are unfamiliar with the appearance of a TIPS on TTE. Being able to recognize this will help avoid misdiagnosis and unnecessary further imaging.     

Technique for transjugular placement of an umbrella filter in a left inferior vena cava

Transjugular placement of a Mobin-Uddin umbrella filter in an anomalous left inferior vena cava to prevent recurrent pulmonary embolization may present technical difficulties. Preforming a slight curve in the applicator wire a short distance from its tip allowed catheterization and proper position of a filter in two cases.     

Superior vena cava syndrome after implantation of a transvenous cardioverter defibrillator

Superior vena cava syndrome is a rare, but nevertheless wellknown complication of permanent pacemaker implantation. Nowadayscardioverter defibrillators are also routinely implanted transvenously. A superior vena cava syndrome occurred in a 48-year-old female2 years after implantation of cardioverter defibrillator. Theclinical problem, in the presence of a predisposing thrombophiliccondition (circulating lupus anticoagulant), resolved only partiallyafter treatment with thrombolytics and oral anticoagulation.This syndrome should be recognized as a possible important complicationof defibrillator therapy and requires lifelong anticoagulation.     

Successful Treatment of Malignant Superior Vena Cava Syndrome Using a Stent-Graft

We report successful outcomes after endovascular placement of a stent graft in a 74- and a 77-year-old men, both of whom had malignant superior vena cava syndrome caused by squamous cell carcinoma. In each patient, successful palliation of the malignant superior vena cava syndrome was achieved by placement of a stent graft. No procedure-related complications were observed. The patients were asymptomatic until their deaths, seven and 14 months after stent graft placement, respectively.