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Facial Plastic Surgery Clinics of North... May 2023Local tissue flaps are a fundamental technique in cutaneous reconstruction. Reducing the risk of flap failure is of critical importance. The intrinsic vascularity of a... (Review)
Review
Local tissue flaps are a fundamental technique in cutaneous reconstruction. Reducing the risk of flap failure is of critical importance. The intrinsic vascularity of a flap is the most important determinant of success. Good surgical techniques, including flap design, delicate tissue handling, and tension-less closure, help reduce the risk of flap compromise. Determining the etiology of compromise, including arterial, venous, hematologic, or infectious, is the first step in salvaging a failing flap. Common causes include pedicle kinking, hematoma, pressure/tension, systemic patient factors, and poor surgical technique. Swift action to restore perfusion or venous outflow through numerous strategies is required.
Topics: Humans; Plastic Surgery Procedures; Surgical Flaps; Postoperative Complications; Veins; Hematoma
PubMed: 37001930
DOI: 10.1016/j.fsc.2023.01.006 -
Computed tomography and magnetic resonance imaging of congenital thoracic systemic venous anomalies.Pediatric Radiology May 2023We present the imaging findings of thoracic systemic venous anomalies diagnosed by computed tomography and magnetic resonance imaging. Persistent left superior vena cava...
We present the imaging findings of thoracic systemic venous anomalies diagnosed by computed tomography and magnetic resonance imaging. Persistent left superior vena cava is the commonest anomaly of the thoracic systemic veins encountered either incidentally as an isolated finding or associated with congenital heart disease. Inferior vena cava (IVC) interruption with azygos continuation is the second most common anomaly, which may also be isolated or be associated with left isomerism syndrome. The article will also discuss other rarer systemic venous anomalies including retroaortic brachiocephalic vein and IVC drainage into the left atrium. Finally, the impact of pre-procedure reporting of thoracic systemic venous anomalies on the choice of intervention and patient outcome will be addressed.
Topics: Humans; Vena Cava, Superior; Vena Cava, Inferior; Magnetic Resonance Imaging; Tomography, X-Ray Computed; Heterotaxy Syndrome; Vascular Malformations
PubMed: 36600100
DOI: 10.1007/s00247-022-05570-w -
Folia Morphologica 2022Abnormal systemic vein development produces anomalous veins, which - in the case of persistent left superior vena cava and/or left brachiocephalic vein - exhibit...
Double superior vena cava and left brachiocephalic vein agenesis: a rare systemic vein anomaly and potential source of cardiac implantable electronic device and central venous catheter placement complications.
Abnormal systemic vein development produces anomalous veins, which - in the case of persistent left superior vena cava and/or left brachiocephalic vein - exhibit considerable topographic and morphometric differences in comparison with their usual anatomy. The nature and extent of those developmental anomalies - detected during intravenous procedures, such as cardiac implantable electronic device (CIED) lead insertion or central venous catheter placement - may hinder the procedure itself and/or adversely affect its outcome, both at the stage of cardiac lead advancement through an abnormally shaped vessel and lead positioning within the heart. This may lead to problems in achieving optimal sensing and pacing parameters and in ensuring that the patient cannot feel the pacing impulses. These events accompanied a de novo CIED implantation procedure in the patient with a double superior vena cava and left brachiocephalic vein agenesis, who ultimately required reoperation.
Topics: Humans; Vena Cava, Superior; Brachiocephalic Veins; Central Venous Catheters; Vascular Malformations; Heart
PubMed: 34699053
DOI: 10.5603/FM.a2021.0108 -
British Journal of Clinical Pharmacology Sep 19941. Venous resistance contributes very little to total peripheral resistance; more than half of the total blood volume, however, is contained in the extrathoracic veins.... (Review)
Review
1. Venous resistance contributes very little to total peripheral resistance; more than half of the total blood volume, however, is contained in the extrathoracic veins. Owing to marked differences between venous and arterial anatomy and physiology, studies on veins and arteries usually require different methodological approaches. Whereas for arteries the most relevant parameters are resistance, pressure and flow, for veins volume and compliance are most important. For studies of general aspects of the peripheral circulatory system, venous occlusion plethysmography is probably the most useful method. The determination of both the rate of rise in limb volume and the total volume rise after inflating a proximally applied occlusion cuff to a subdiastolic pressure permits the concomitant estimation of both arterial flow and venous compliance. 2. Studies of direct pharmacological or physiological effects on veins, interactions of various pharmacological or physiological stimuli, or pathophysiological changes in venous responsiveness have been facilitated by the development of investigational techniques relying on direct measurements of the compliance of single human veins in vivo. One of these, relying on the use of a linear variable differential transformer (LVDT) for determining changes in the compliance of superficial veins at a standardized congestion pressure, has been found very suitable for the practical application in both patients and healthy subjects. 3. Physiological studies were carried out on the effect of age, exercise, temperature, and the menstrual cycle on venous compliance and venous responsiveness to various stimuli. In addition, interindividual variability in venous responsiveness in monozygotic and dizygotic twins and in unrelated subjects was investigated, and studies on the function of the endothelium were carried out in man in vivo. 4. Pathophysiological studies using this technique were reported from patients with hypertension, orthostatic hypotension, myocardial infarction, varicosis, cystic fibrosis, asthma, diabetes, systemic sclerosis, and cluster headache. 5. Clinical pharmacological studies represent a most important field for the use of this method. Studies were carried out on the effects of a large number of constrictor and dilator agents, and also on drug interactions on human veins in vivo. Venoconstriction was observed after local administration of alpha-adrenoceptor and 5-HT-receptor agonists, ergot derivatives, angiotensinogen, angiotensin I and II, and several prostaglandins. 6. Owing to the low venous tone present under effects can usually be quantified only on veins e.g. noradrenaline or 5-hydroxytryptamine. Under these conditions dilatation was observed after the administration of beta-adrenoceptor agonists, cholinergic (muscarinic) agonists, nitrates, calcium antagonists, bradykinin, substance P and several prostaglandins.
Topics: Aging; Animals; Blood Pressure; Cardiovascular Diseases; Compliance; Diabetes Complications; Diabetes Mellitus; Endothelium, Vascular; Exercise; Female; Humans; Hypertension; Hypotension, Orthostatic; Plethysmography; Raynaud Disease; Vascular Resistance; Veins
PubMed: 7826819
DOI: 10.1111/j.1365-2125.1994.tb04341.x -
United European Gastroenterology Journal Jun 2020Type-C hepatic encephalopathy is a complex neurological syndrome, characteristic of patients with liver disease, causing a wide and complex spectrum of nonspecific... (Review)
Review
Type-C hepatic encephalopathy is a complex neurological syndrome, characteristic of patients with liver disease, causing a wide and complex spectrum of nonspecific neurological and psychiatric manifestations, ranging from a subclinical entity, minimal hepatic encephalopathy, to a deep form in which a complete alteration of consciousness can be observed: overt hepatic encephalopathy. Overt hepatic encephalopathy occurs in 30-40% of patients. According to the time course, hepatic encephalopathy is subdivided into episodic, recurrent and persistent. Diagnostic strategies range from simple clinical scales to more complex psychometric and neurophysiological tools. Therapeutic options may vary between episodic hepatic encephalopathy, in which it is important to define and treat the precipitating factor and hepatic encephalopathy and secondary prophylaxis, where the standard of care is non-absorbable disaccharides and rifaximin. Grey areas and future needs remain the therapeutic approach to minimal hepatic encephalopathy and issues in the design of therapeutic studies for hepatic encephalopathy.
Topics: Administration, Oral; Anti-Bacterial Agents; Drug Therapy, Combination; Endovascular Procedures; Enema; Hepatic Encephalopathy; Hepatic Veins; Humans; Imaging, Three-Dimensional; Lactulose; Liver Cirrhosis; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Portal Vein; Prevalence; Psychometrics; Rifaximin; Severity of Illness Index; Stents; Tomography, X-Ray Computed; Urinary Tract Infections
PubMed: 32213035
DOI: 10.1177/2050640620909675 -
European Journal of Vascular and... Aug 2007The aim of this article is to review the published English literature on aetiology, pathology, clinical presentation, diagnostic methods and treatment of renal vein... (Review)
Review
OBJECTIVE
The aim of this article is to review the published English literature on aetiology, pathology, clinical presentation, diagnostic methods and treatment of renal vein thrombosis.
MATERIALS AND METHODS
We searched the published literature from Medline & Pubmed using keywords renal vein thrombosis, anti-phospholipid syndrome and nephrotic syndrome. Data was extracted from individual case reports, case series, articles on pathology, diagnostic tests, treatment modalities, and previous reviews. Case reports which did not add any new information were excluded.
RESULTS
We selected 60 references based on the above criteria. Renal vein thrombosis is relatively rare. CT angiography is considered the investigation of choice. Alternatives include MR angiography or renal venography in highly selected patients. As the condition is relatively uncommon, consensus on the best form of therapy for this condition has been slow to evolve. The trend in management has shifted to non-surgical therapies particularly systemic anticoagulation except in highly selected group of patients.
Topics: Anticoagulants; Humans; Magnetic Resonance Angiography; Patient Selection; Phlebography; Practice Guidelines as Topic; Renal Veins; Tomography, X-Ray Computed; Treatment Outcome; Vascular Surgical Procedures; Venous Thrombosis
PubMed: 17543556
DOI: 10.1016/j.ejvs.2007.02.017 -
Medicine Jan 2019An in-utero re-classification of umbilical-portal-systemic venous shunt (UPSVS) has recently been proposed. We retrospectively reviewed the sonograms of a large cohort... (Observational Study)
Observational Study
An in-utero re-classification of umbilical-portal-systemic venous shunt (UPSVS) has recently been proposed. We retrospectively reviewed the sonograms of a large cohort of fetuses, identified and analyzed UPSVS cases, and presented the prenatal sonographic characteristics, birth outcomes, and follow-up results following the new classification system.Sonograms and clinical data of all participants who visited our departments from April 2016 to July 2018 were retrospectively reviewed. Identified cases of UPSVS were analyzed according to the new classification: Type I: umbilical-systemic shunt (USS); Type II: ductus venosus-systemic shunt (DVSS); Type IIIa: intrahepatic portal-systemic shunt (IHPSS) and Type IIIb: extrahepatic portal-systemic shunt (EHPSS). Postnatal follow-ups ranged from 3 months to 1 year.A total of 10 UPSVS cases were identified in 61,082 fetuses: 4 with Type I, 3 with Type II and 3 with Type IIIa. All 4 cases of USS had complete agenesis of the portal venous system, and had the umbilical vein drained into the inferior vena cava. Two USS cases also had trisomy 21. Pregnancy was terminated in all cases with a Type I shunt. Two fetuses with DVSS had normal portal venous system and were born full term. The pregnancy of 1 DVSS case was terminated due to the detection of trisomy 21. Three cases were IHPSS with full-term birth. One had chromosomal abnormality and 1 had surgery to repair the shunt 12-days post birth. In the 2 cases that did not receive repair surgery, sonographic examination revealed the portal-hepatic venous shunt was not closed at the 6-month follow-up period. However, the 1 case that had repair surgery appeared healthy at the 3-month follow-up period.UPSVS is extremely rare. Type I shunts have the poorest prognosis, and the presence of the intrahepatic portal venous system is key to live birth in UPSVS regardless of types. Chromosomal abnormalities and other organ anomalies can occur in any types of UPSVS. Therefore, karyotyping and examination of other organs should be performed once UPSVS is detected.
Topics: Disease Progression; Female; Follow-Up Studies; Humans; Infant, Newborn; Male; Portal Vein; Pregnancy; Prognosis; Retrospective Studies; Ultrasonography, Prenatal; Vascular Malformations
PubMed: 30633228
DOI: 10.1097/MD.0000000000014125 -
BMC Pulmonary Medicine Jul 2020Plasma levels of cell-free DNA (cf-DNA) are known to be elevated in sepsis and high levels are associated with a poor prognosis. Mechanical ventilation affects systemic...
BACKGROUND
Plasma levels of cell-free DNA (cf-DNA) are known to be elevated in sepsis and high levels are associated with a poor prognosis. Mechanical ventilation affects systemic inflammation in which lung-protective ventilation attenuates the inflammatory response. The aim was to study the effect of a lung protective ventilator regime on arterial and organ-specific venous blood as well as on trans-organ differences in cf-DNA levels in a porcine post-operative sepsis model.
METHOD
One group of anaesthetised, domestic-breed, 9-12 weeks old, pigs were ventilated with protective ventilation (V 6 mL x kg, PEEP 10 cmHO) n = 20. Another group, ventilated with a medium high tidal volume and lower PEEP, served as a control group (V 10 mL x kg, PEEP 5 cm HO) n = 10. Blood samples were taken from four sources: artery, hepatic vein, portal vein and, jugular bulb. A continuous endotoxin infusion at 0.25 μg x kg x h for 5 h was started following 2 h of laparotomy, which simulated a surgical procedure. Inflammatory cytokines and cf-DNA in plasma were analysed and trans-organ differences calculated.
RESULTS
The protective ventilation group had lower levels of cf-DNA in arterial (p = 0.02) and hepatic venous blood (p = 0.03) compared with the controls. Transhepatic differences in cf-DNA were lower in the protective group, compared with the controls (p = 0.03). No differences between the groups were noted as regards the transcerebral, transsplanchnic or the transpulmonary cf-DNA differences.
CONCLUSIONS
Protective ventilation suppresses arterial levels of cf-DNA. The liver seems to be a net contributor to the systemic cf-DNA levels, but this effect is attenuated by protective ventilation.
Topics: Animals; Cell-Free Nucleic Acids; Cytokines; Disease Models, Animal; Female; Hepatic Veins; Inflammation; Male; Peak Expiratory Flow Rate; Portal Vein; Postoperative Complications; Respiration, Artificial; Sepsis; Swine; Tidal Volume
PubMed: 32736620
DOI: 10.1186/s12890-020-01239-y -
BMC Pregnancy and Childbirth Apr 2023To investigate the ultrasonographic classification of fetal umbilical-portal-systemic venous shunts (UPSVS) and the correlations with fetal chromosomal abnormalities.
OBJECTIVE
To investigate the ultrasonographic classification of fetal umbilical-portal-systemic venous shunts (UPSVS) and the correlations with fetal chromosomal abnormalities.
METHODS
We retrospectively analyzed the ultrasound characteristics and the corresponding chromosomal abnormalities of 26 cases of fetal UPSVS prenatally diagnosed.
RESULTS
A total of 26 fetuses diagnosed as UPSVS were included, including four cases of type I UPSVS, ten of type II, three of type IIIA, and nine of type IIIB. Four cases of type I were all complicated by fetal heart enlargement and heart insufficiency, of which one case had multiple malformations, and all four cases terminated pregnancies. Six of ten cases of type II terminated pregnancies, including four of Down's syndrome, one of twin reversed arterial perfusion sequence, one of fetal edema but with normal copy number variation (CNV) by chorionic villus sampling. The other four of ten cases were isolated type II with normal chromosomes, which were delivered at full term and were normal in growth and development when followed up 34 months after birth. Three cases of type IIIA all terminated pregnancies, of which one had multiple malformations, one had right multicystic dysplastic kidney, and one had fetal heart enlargement and heart failure. Among nine of type IIIB, seven with chromosomal abnormalities and/ or complicated malformations terminated pregnancies, and two with isolated type IIIB and normal chromosomes were delivered at full term, and were normal in growth and development (one was followed up to 33 months after birth and the other 20 months after birth).
CONCLUSION
Fetal UPSVS can be clearly diagnosed and typed by prenatal ultrasonography. Fetal prognosis is determined by the types of UPSVS and complicated malformations and/ or chromosomal abnormalities. The probability of fetal chromosomal abnormalities in UPSVS fetuses is related to the ultrasonographic classification.
Topics: Female; Humans; Pregnancy; Abnormalities, Multiple; Cardiomegaly; Chromosome Aberrations; DNA Copy Number Variations; Fetal Heart; Retrospective Studies; Ultrasonography, Prenatal; Umbilical Veins
PubMed: 37038108
DOI: 10.1186/s12884-023-05525-5 -
BMJ Case Reports Jul 2021Abnormal communications between the systemic and pulmonary venous systems are rare but can present as a opacity on chest radiograph. A solitary vessel communicating as a... (Review)
Review
Abnormal communications between the systemic and pulmonary venous systems are rare but can present as a opacity on chest radiograph. A solitary vessel communicating as a fistula directly between the systemic arterial circulation and the pulmonary venous system is not widely described. These may have significant implications in the long-term cardiovascular health of an individual acting as a left to right shunt. There is no clear consensus as to the management, but surgical management and endovascular embolisation have been successfully used. We present a case where a systemic arteriaopulmonary fistula originating from the abdominal aorta and connecting to the right inferior pulmonary vein manifested as an incidental finding on a chest radiograph and was further evaluated on cross-sectional imaging in a young patient. Chest radiographs are non-specific and it is important to be aware of the less frequent but important pathologies that can be picked up on plain chest radiographs, which inturn should warrant further investigation. This is presented in conjunction with a review of the available literature along with a discussion regarding the differential diagnosis and management applicable to the general clinician.
Topics: Aorta, Abdominal; Fistula; Humans; Lung; Pulmonary Veins
PubMed: 34326108
DOI: 10.1136/bcr-2021-241644