Midline skull tumors

2015 ◽  
Vol 42 (S1) ◽  
pp. S44-S45
Author(s):  
M Maleki
Keyword(s):  
Rare Case ◽  
Venous Return ◽  
Venous Blood ◽  
Subtotal Resection ◽  
Venous Blood Flow ◽  
Venous Flow ◽  
Posterior Portion ◽  
Sagittal Sinus ◽  
Skull Tumors ◽  
Visual Blurring

Introduction: Variety of tumors could involve the skull; however, very few may occur over the midline. Some may affect venous blood flow of superior sagittal sinus. Few challenging cases are presented Material: 1-Rare case of osteoblastoma over the torcula, (headache, visual symptoms, papilledema, VI nerve palsy). 2- Rare case of metastatic liposarcoma involving midsagital sinus, partially occluding it (headache and visual blurring). 3- A huge atypical (grade2) meningioma over the vertex Method: Case #1, the tumor over the venous confluences (torcula) was removed easily, without any complications. Complete resolution of symptoms Case #2, complete en-block resection of tumor, with sacrifice of mid-sagittal portion of sinus, without any neurological sequellae. Case #3, subtotal resection, followed by radiotherapy.Discussion &Conclusion: Anterior 3rd of sagital sinus could be sacrificed (if necessary), without major consequences. However, whenever mid or posterior portion of the sinus is involved, interruption of venous flow could pose very serious complications. Occasionally, chronic compression of sinus may force increasing collateral venous return, in which case one may attempt a complete resection of the lesion, with sacrifice of part of the sinus, as in our second case. In the region of torcula, however, one should be very careful not to damage it

Superior sagittal sinus thrombosis induced by thyrotoxicosis

2001 ◽  
Vol 94 (1) ◽  
pp. 130-132 ◽  
Author(s):  
Cheng-Shyuan Rau ◽  
Chun-Chung Lui ◽  
Cheng-Loong Liang ◽  
Han-Jung Chen ◽  
Yeh-Lin Kuo ◽  
...  
Keyword(s):  
Intracranial Hemorrhage ◽  
Superior Sagittal Sinus ◽  
Sinus Thrombosis ◽  
Venous Blood ◽  
Fibrinogen Concentration ◽  
Venous Blood Flow ◽  
Content Type ◽  
Sagittal Sinus ◽  
Low Protein ◽  
Diffuse Goiter

✓ There is a wide variety of disorders associated with thrombosis of the superior sagittal sinus (SSS), including infectious disease, noninfectious conditions such as vasculitis and hypercoagulable states, and complications arising from pregnancy or use of oral contraceptive medications. Despite these well-defined associations, approximately 25% of the cases remain idiopathic. In this article the authors describe a patient who was found to have SSS thrombosis while experiencing a thyrotoxic phase of Graves disease. The patient presented with intracerebral hemorrhage, subarachnoid hemorrhage, seizure, coma, a raised fibrinogen concentration, low protein C activity, and atrial fibrillations. Thrombolysis was successfully performed despite the coexistence of thrombosis and intracranial hemorrhage. Patients with thyrotoxicosis and a diffuse goiter may be predisposed to the development of SSS thrombosis, as a result of hypercoagulation and stasis of local venous blood flow. In the present case, a patient in whom thrombosis coexisted with intracranial hemorrhage was successfully treated using thrombolytic therapy.

scholarly journals Effect of spontaneous breathing on umbilical venous blood flow and placental transfusion during delayed cord clamping in preterm lambs

2019 ◽  
Vol 105 (1) ◽  
pp. 26-32 ◽  
Author(s):  
Emma Brouwer ◽  
Arjan B te Pas ◽  
Graeme R Polglase ◽  
Erin V McGillick ◽  
Stefan Böhringer ◽  
...  
Keyword(s):  
Blood Flow ◽  
Body Weight ◽  
Spontaneous Breathing ◽  
Venous Blood ◽  
Vena Cava ◽  
Venous Blood Flow ◽  
Delayed Cord Clamping ◽  
Venous Flow ◽  
Cord Clamping ◽  
Pregnant Sheep

IntroductionDuring delayed umbilical cord clamping, the factors underpinning placental transfusion remain unknown. We hypothesised that reductions in thoracic pressure during inspiration would enhance placental transfusion in spontaneously breathing preterm lambs.ObjectiveInvestigate the effect of spontaneous breathing on umbilical venous flow and body weight in preterm lambs.MethodsPregnant sheep were instrumented at 132–133 days gestational age to measure fetal common umbilical venous, pulmonary and cerebral blood flows as well as arterial and intrapleural (IP) pressures. At delivery, doxapram and caffeine were administered to promote breathing. Lamb body weights were measured continuously and breathing was assessed by IP pressure changes.ResultsIn 6 lambs, 491 out of 1117 breaths were analysed for change in body weight. Weight increased in 46.6% and decreased in 47.5% of breaths. An overall mean increase of 0.02±2.5 g per breath was calculated, and no net placental transfusion was observed prior to cord clamping (median difference in body weight 52.3 [−54.9–166.1] g, p=0.418). Umbilical venous (UV) flow transiently decreased with each inspiration, and in some cases ceased, before UV flow normalised during expiration. The reduction in UV flow was positively correlated with the standardised reduction in (IP) pressure, increasing by 109 mL/min for every SD reduction in IP pressure. Thus, the reduction in UV flow was closely related to inspiratory depth.ConclusionsSpontaneous breathing had no net effect on body weight in preterm lambs at birth. UV blood flow decreased as inspiratory effort increased, possibly due to constriction of the inferior vena cava caused by diaphragmatic contraction, as previously observed in human fetuses.

scholarly journals Fetal brain venous return in complicated pregnancy

2002 ◽  
Vol 51 (1) ◽  
pp. 10-14
Author(s):  
Eduard K. Ailamazyan ◽  
Albert A. Polyanin ◽  
Igor Y. Kogan
Keyword(s):  
Blood Flow ◽  
Venous Return ◽  
Peak Velocity ◽  
Venous Blood ◽  
Fetal Brain ◽  
Venous Blood Flow ◽  
Mean Velocity ◽  
Complicated Pregnancy ◽  
S Peak ◽  
Ventricular Filling

Objective. To estimate the fetal brain venous return in the complicated pregnancy. Methods. Blood flow waveforms (BFW) in jugular vein (JV) were recorded in 162 fetuses from 13 to 40 weeks of normal gestation and in 63 growth restricted fetuses. Peak velocity in ventricular systole (S), peak velocity in early diastole which corresponds to passive ventricular filling (D), peak velocity in atria contraction with active ventricular filling (A), mean velocity (TAV) were measured and pulsatility index (PIV=S-A/TAV), systolic to diastolic ratio (S/D) were calculated. Results. S, D, A, TAV in growth restricted fetuses were significantly greater and PIV, S/D were significantly lower than in normal fetuses after 36 weeks of gestation. Conclusions. The results demonstrate that there are neuroprotective reactions of fetal cerebral venous blood flow after 36 weeks of gestation.

Assessment Of Venous Function After Major Gynecological Surgery With Heparin-Dihydroergotamine In The Prophylaxis Of DVT

1981 ◽  
Author(s):  
S Kunz ◽  
O M Burth ◽  
E Zimmerer
Keyword(s):  
Doppler Ultrasonography ◽  
Varicose Veins ◽  
Synergistic Effects ◽  
Venous Blood ◽  
Haemodynamic Effect ◽  
Venous Blood Flow ◽  
Venous Flow ◽  
Venous Function ◽  
The Right ◽  
Clinical Conditions

Dihydroergotamine (DHE) has been shown to have synergistic effects with heparin in the prophylaxis of DVT. To assess the hemodynamic efficacy of DHE in clinical conditions, 72 patients undergoing hysterectomy were randomly allocated to three groups receiving heparin/DHE, heparin or acenocoumarol. Venous function was measured by occlusion plethysmography and doppler ultrasonography. Diagnosis of DVT by 125-I-fibrinogen test.Results: Doppler Ultrasonography: The velocity of venous flow in the left V. femoralis was lower than at the right side in all groups before hysterectomy. After surgery, a significant increase from 11.2 to 15.5 cm/sec in the heparin/DHE group could be demonstrated. Heparin and acenocoumarol patients showed a tendency to lower venous return. The differences were more marked in women with vaginal hysterectomy.Occlusion plethysmography: No differences in venous capacity before and after operation could be found in the heparin and acenocoumarol group. A significant reduction (16%) was measured in heparin/DHE treated patients. The maximal venous outflow also was significantly reduced in this group (18%). This difference also was found in patients with varicose veins.Conclusions: The data confirm that DHE increases the velocity of venous blood flow in the legs by constricting the capacitance vessels. This haemodynamic effect could be demonstrated in clinical conditions.

Do we still need compression bandages? Haemodynamic effects of compression stockings and bandages

2006 ◽  
Vol 21 (3) ◽  
pp. 132-138 ◽  
Author(s):  
H Partsch
Keyword(s):  
Flow Velocity ◽  
Venous Blood ◽  
Haemodynamic Effects ◽  
Venous Blood Flow ◽  
Compression Stockings ◽  
Venous Flow ◽  
Elastic Compression ◽  
Compression Bandages ◽  
Interface Pressures ◽  
Pumping Function

Objective: To compare haemodynamic data obtained with elastic compression stockings and inelastic compression material applied with different pressure ranges on the lower extremities. Methods: Haemodynamic effects of compression therapy were demonstrated by measuring venous flow velocity, venous volume, venous reflux and venous pumping function using radioisotopes, phlebography, water displacement volumetry, duplex, air plethysmography, foot volumetry and phlebodynamometry. Results: Light-compression stockings are able to increase venous blood flow velocity in the supine position and to prevent leg swelling after prolonged sitting and standing. In the upright position an interface pressure of more than 50 mmHg is needed for an intermittent occlusion of incompetent veins and for a reduction of ambulatory venous hypertension during walking. Such high interface pressures may rather be achieved by short-stretch, multilayer bandages than by an elastic stocking. Conclusion: Elastic compression stockings exerting interface pressures up to 40 mmHg are effective in preventing or reducing oedema. Multilayer compression bandages with a pressure over 40 mmHg additionally improve severely disturbed venous pumping function.

scholarly journals КОМПРЕСІЙНА АСФІКСІЯ

2019 ◽  
Vol 1 (11(41)) ◽  
pp. 26-31
Author(s):  
Хоботова Наталія Володимирівна ◽  
Єхалов Василій Вталійович
Keyword(s):  
Venous Blood ◽  
Intrathoracic Pressure ◽  
Shoulder Girdle ◽  
External Pressure ◽  
The Body ◽  
Whole Body ◽  
Venous Blood Flow ◽  
Venous Flow ◽  
Septic Complications ◽  
The Face

Compression asphyxia is a type of mechanical asphyxia when breathing stops with external pressure on the body, which leads to the absence of respiratory movements and disrupts venous return from the head. With a strong compression of the chest, a reflex spasm of the glottis occurs, which contributes to an increase in intrathoracic pressure, reverse venous blood flow and an obstruction of venous flow to the heart occur. A sharp increase in intracranial pressure and venous congestive congestion / hemorrhage deepen central respiratory failure. Mild degree: mental agitation; puffy face, slight cyanosis; individual conjunctival petechiae; tachypnea. Medium degree: light or heavy stunning, lost orientation; the face is puffy, cyanotic; swelling of the cervical veins, acrocyanosis; multiple petechiae that spread across the face, neck, conjunctiva of the eyes, inspiratory dyspnea, visual impairment. Severe degree: stupor or coma, sharp cyanosis of the whole body, exophthalmos; swelling of the face, neck and shoulder girdle, arms, multiple petechiae of the face, neck, arms, legs, conjunctiva of the eyes, swelling of the cervical veins, cyanosis and edema of the upper half of the body; superficial breathing, frequent, in the absence of treatment passes to agonal and apnea. Intensive care includes analgesia, oxygenation or mechanical ventilation, anticonvulsant, dehydration and decongestant therapy, prevention of acute kidney damage, DIC, septic complications, and treatment of posthypoxic encephalopathy.

scholarly journals Arterio-Venous Branchial Blood Flow in the Atlantic Cod Gadus Morhua

1992 ◽  
Vol 165 (1) ◽  
pp. 73-84 ◽  
Author(s):  
LENA SUNDIN ◽  
STEFAN NILSSON
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
Atlantic Cod ◽  
Vascular System ◽  
Venous Blood ◽  
Venous Blood Flow ◽  
Venous Flow ◽  
Flow Measurements ◽  
Vasomotor Function

We have estimated the branchial venous blood flow in the Atlantic cod by direct single-crystal Doppler blood flow measurements in vivo. In the undisturbed animal, this flow amounts to 1.7 ml min−1 kg−1, which corresponds to about 8 % of the cardiac output. Studies of both an isolated perfused gill apparatus in situ and simultaneous measurements of cardiac output and branchial venous flow in vivo were made to assess the effects of some putative vasoregulatory substances. Adrenaline dilates the arterio-arterial pathway and constricts the arterio-venous pathway, thus decreasing branchial venous drainage. 5-Hydroxytryptamine (5-HT), in contrast, produced marked vasoconstriction in the arterio-arterial pathway of the branchial vasculature, increasing the branchial venous blood flow. Cholecystokinin-8 (CCK-8) and caerulein produced similar cardiovascular effects, with marked constriction of both arterio-arterial and arterio-venous pathways. The study demonstrates the ability of the vascular system of the gills to regulate the distribution of branchial blood flow, and summarizes the vasomotor effects of some substances with possible vasomotor function in the cod gills.

Determining an Appropriate To-Keep-Vein-Open (TKVO) Infusion Rate for Peripheral Intravenous Catheter Usage

2021 ◽  
Author(s):  
Barry Doyle ◽  
Lachlan Kelsey ◽  
Peter J. Carr ◽  
Andrew Bulmer ◽  
Samantha Keogh
Keyword(s):  
Shear Stress ◽  
Infusion Rate ◽  
Venous Blood ◽  
Blood Stasis ◽  
Venous Blood Flow ◽  
Venous Flow ◽  
Flow Rates ◽  
Fluid Load ◽  
Peripheral Intravenous Catheter ◽  
Intravenous Catheters

Highlights Abstract Background: Evidence to support an optimum continuous to-keep-vein-open (TKVO) infusion rate for peripheral intravenous catheters (PIVCs) is lacking. The aim of this study was to simulate typical TKVO rates, in combination with flushing, to better understand TKVO in relation to PIVC patency. Methods: We simulated saline infusion through a 20-gauge PIVC in 2 forearm veins (3.3 and 2.2 mm) using computational fluid dynamics under various venous flow rates (velocities 3.7–22.1 cm/s), with a saline flush rate of 1 mL/s and TKVO infusion rates of 10, 20, and 40 mL/h. We determined TKVO efficacy using the stream of saline clearing the stasis region at the device tip and the shear stress acting on the vein. Results: At 10 mL/h TKVO rate, blood stasis occurs around the PIVC tip as saline is pulled into the faster-moving venous blood flow, creating the blood recirculation (stasis) zone at the device tip. When TKVO increases >20 mL/h, this stasis diminishes, and the likelihood of patency increases. Shear stress on the vein is negligible during TKVO but increases 10- to 19-fold when flushing the small and large veins investigated here. Conclusions: Low TKVO rates (10 mL/h) may not clear the PIVC tip and keep the device patent. Based on our simulations, we propose a TKVO rate of at least 20 mL/h could be used in practice; however, 30–40 mL/h appears most effective across different venous flow rates and peripheral vein sizes. However, this additional fluid load must be carefully considered based on the needs of each patient.

scholarly journals Transjugular Intrahepatic Portosystemic Shunt for Maintenance of Portal Venous Patency in Liver Transplant Candidates

2013 ◽  
Vol 3 ◽  
pp. 29 ◽  
Author(s):  
Ron Charles Gaba ◽  
Ahmad Parvinian
Keyword(s):  
Liver Transplant ◽  
Transjugular Intrahepatic Portosystemic Shunt ◽  
Venous Blood ◽  
Portosystemic Shunt ◽  
Venous Blood Flow ◽  
Venous Flow ◽  
Vein Thrombosis ◽  
Surgical Complexity ◽  
Intrahepatic Portosystemic Shunt ◽  
Transplant Candidates

Maintenance of portal venous patency is vital to liver transplant candidates, as the presence of portal vein thrombosis (PVT) adversely impacts clinical outcomes by increasing surgical complexity and decreasing postoperative survival. By enhancing portal venous blood flow, transjugular intrahepatic portosystemic shunt (TIPS) creation may enable clearance of PVT and preservation of portal venous patency in cirrhotic patients. Herein, we describe four cases in which TIPS produced and sustained an open portal venous system in liver transplant candidates with partial PVT. All patients demonstrated rapid and effective flow-enabled clearance of clot and intermediate to long-term preservation of portal venous flow. On this basis, we propose that maintenance of portal venous patency in liver transplant candidates with partial PVT represents a developing indication for TIPS.

Influence of lung volume and alveolar pressure on reverse pulmonary venous blood flow

1992 ◽  
Vol 73 (1) ◽  
pp. 195-199 ◽  
Author(s):  
T. Obermiller ◽  
S. Lakshminarayan ◽  
S. Willoughby ◽  
J. Mendenhall ◽  
J. Butler
Keyword(s):  
Lung Volume ◽  
Left Atrial ◽  
Venous Blood ◽  
Pulmonary Veins ◽  
Left Lung ◽  
Blood Gases ◽  
Venous Blood Flow ◽  
Alveolar Pressure ◽  
Artery Ligation ◽  
Venous Flow

We have reported that left atrial blood refluxes through the pulmonary veins to gas-exchanging tissue after pulmonary artery ligation. This reverse pulmonary venous flow (Qrpv) was observed only when lung volume was changed by ventilation. This was believed to drive Qrpv by alternately distending and compressing the alveolar and extra-alveolar vessels. Because lung and pulmonary vascular compliances change with lung volume, we studied the effect of positive end-expiratory pressure (PEEP) on the magnitude of Qrpv during constant-volume ventilation. In prone anesthetized goats (n = 8), using the right lung to maintain normal blood gases, we ligated the pulmonary and bronchial arterial inflow to the left lung and ventilated each lung separately. A solution of SF6, an inert gas, was infused into the left atrium. SF6 clearance from the left lung was determined by the Fick principle at 0, 5, 10, and 15 and again at 0 cmH2O PEEP and was used to measure Qrpv. Left atrial pressure remained nearly constant at 20 cmH2O because the increasing levels of PEEP were applied to the left lung only. Qrpv was three- to fourfold greater at 10 and 15 than at 0 cmH2O PEEP. At these higher levels of PEEP, there were greater excursions in alveolar pressure for the same ventilatory volume. We believe that larger excursions in transpulmonary pressure during tidal ventilation at higher levels of PEEP, which compressed alveolar vessels, resulted in the reflux of greater volumes of left atrial blood, through relatively noncompliant extra-alveolar veins into alveolar corner vessels, and more compliant extra-alveolar arteries.

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