extravascular


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Related to extravascular: extravascular fluid

extravascular

 [ek″strah-vas´ku-ler]
situated or occurring outside a vessel or the vessels.

ex·tra·vas·cu·lar

(eks'tră-vas'kyū-lăr),
Outside the blood vessels or lymphatics or of any special blood vessel.

extravascular

(ĕk′strə-văs′kyə-lər)
adj.
1. Located or occurring outside a blood or lymph vessel.
2. Lacking vessels; nonvascular.

hemoglobinuria

Hematology The presence of Hb in the urine which, if of sufficient quantity, colors urine, the intensity of which directly correlates with the quantity of Hb. See Paroxysmal cold hemoglobinuria, Paroxysmal nocturnal hemoglobinuria.
hemolysis Destruction or lysis of RBCs
Hemolysis
Intracorpuscular hemolysis
•  Membrane defects, eg hereditary elliptocytosis, spherocytosis, stomatocytosis and paroxysmal nocturnal hemoglobinuria
•  Metabolic defects, eg G6PD, pyruvate kinase deficiency
•  Abnormal Hbs see Hemoglobin.
Extracorpuscular hemolysis
1º immune reactions, eg autoimmune hemolytic anemia
2º immune reactions, due to
• Infections, eg Bartonella, Clostridia, malaria, sepsis
• Neoplasia, eg lymphoma, leukemias
• Drug reactions due to the 'Innocent bystander' phenomenon (drug-antibody complex activates complement, causing intravascular hemolysis, eg quinidine), hapten-mediated —a protein-bound drug attaches to the red cell membrane, eliciting an immune response when the hapten-protein complex is recognized as foreign, evoking an immune response, eg penicillin acting as a hapten
• Induction of autoimmunity by RBC antigen alterations, eg Rh antigen
Physical, eg thermal, concentrated glycerol due to inadequate washing of frozen blood, bladder irrigation, cardiac valves
Extravascular Less severe, IgG-mediated and does not activate complement, eg Rh, Kell, Duffy Laboratory ↓ haptoglobin, ↓ T1/2 of circulating RBCs, ↑ indirect BR as liver capacity to conjugate BR–ergo direct BR is overwhelmed by massive hemolysis, ↑ LDH, Hb in blood and urine, hemosiderinuria, MetHb and metalbumin, ↑ urobilinogen in urine and feces, ↑ in acid phosphatase, K+, and prostatic acid phosphatase Clin Chem 1992; 38:575; peripheral smears demonstrate anisocytosis, polychromatophilia, nucleated RBCs, basophilic stippling; immune hemolysis is suggested by spherocytes NEJM 2000; 342:722cpc
Intravascular More severe, IgM-mediated and requires complement activation, eg ABO blood groups Laboratory ↑ free Hb  Note: Clinically significant hemolysis is usually detected by hemagglutination, less commonly by hemolysis per se, which detects anti-P,
-P1, -PP1Pk, -Jka, -Lea, occasionally also anti-Leb and -Vel

extravascular

Outside a blood vessel or the circulatory system.
References in periodicals archive ?
The extravascular stent was shown to be safe postoperatively without migration, collapse, or erosion.
Mannitol acts as an immediate plasma expander by drawing fluid from extravascular to intravascular space, as a result improving cerebral blood flow which in turn causes cerebral vasoconstriction.
DCE-MRI relies on the fact that a bolus of contrast agent passing through the capillary bed is transiently confined within the vascular space before passing rapidly into the extravascular extracellular space at a rate determined by the permeability of the microvessels, their surface area, and blood flow [17,18].
HAPE severity according to HULTGREN grades Grade 1 (mild) 3 Grade 2 (moderate) 21 Grade 3 (serious) 93 Grade 4 (severe) 9 Patients of non-HAPE (number %) 22 (14.9) Bronchitis 1 (0.7) Acute upper respiratory infection 4 (2.7) Acute mild high-altitude disease 17 (11.5) Radiologic score of extravascular lung water of HAPE (before treatment) Median (IQR) * 39 (29-48) Range 0-83 * Interquartile range (IQR) expressed as the 25th and 75th percentiles.
Assessment of cardiac preload and extravascular lung water by single transpulmonary thermodilution.
Neutrophils may therefore be needed to phagocytize sulphonamide antibodies-coated red blood cells leading to their ultimate extravascular destruction.
The literature mentions three mechanisms by which the nervous system may be affected, proposed by Drachman: 1) necrotizing vasculitis involving brain, spinal and radicular vessels; 2) contiguity extravascular granulomas in the paranasal sinuses, nasal cavities or orbits; 3) primary necrotizing granulomas in the skull, meninges, cranial nerves or brain (3,11,5).
[10], a study conducted in healthy volunteers reported the presence of higher extravascular haemolysis after older RBC transfusion (storage of 40-42 days) compared with fresh blood (storage of 3-7 days) illustrating the possible harmful effect of iron delivery.
The degree of contrast medium enhancement is the result of a combination of complex factors including the rate, amount, concentration of contrast material administered; the speed of injection; the timing of the scans; cardiac output; extravascular redistribution; and renal filtration and excretion of contrast material.
The transpulmonary thermodilution provided the following: (1) preload parameters: global end-diastolic volume index (GEDVI), intrathoracic blood volume index (ITBVI), and stroke volume variation (SVV); (2) cardiac parameters: CO, cardiac index (CI), and global ejection fraction (GEF); (3) afterload parameters: systemic vascular resistance index (SVRI); and (4) lung parameters: extravascular lung water index (EVLWI) and pulmonary vascular permeability index (PVPI).