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Autonomic Nerve Block
Interruption of sympathetic pathways, by local injection of an anesthetic agent, at any of four levels: peripheral nerve block, sympathetic ganglion block, extradural block, and subarachnoid block.
Heart Block
Impaired conduction of cardiac impulse that can occur anywhere along the conduction pathway, such as between the SINOATRIAL NODE and the right atrium (SA block) or between atria and ventricles (AV block). Heart blocks can be classified by the duration, frequency, or completeness of conduction block. Reversibility depends on the degree of structural or functional defects.
Interatrial Block
Impaired or delayed impulse conduction between the right and left HEART ATRIA. Advanced interatrial blocks are often associated with arrhythmias (e.g., ATRIAL FLUTTER; and ATRIAL FIBRILLATION), direct conduction block via the Bachmann's bundle and concomitant left atrial enlargement. Syndrome of advanced interatrial block associated with SUPRAVENTRICULAR TACHYCARDIA is referred to as Bayes syndrome.
Year introduced: 2018
Atrioventricular Block
Impaired impulse conduction from HEART ATRIA to HEART VENTRICLES. AV block can mean delayed or completely blocked impulse conduction.
Year introduced: 2008 (1975)
Bundle-Branch Block
A form of heart block in which the electrical stimulation of HEART VENTRICLES is interrupted at either one of the branches of BUNDLE OF HIS thus preventing the simultaneous depolarization of the two ventricles.
Cervical Plexus Block
A blocking of NEURAL CONDUCTION in the network of nerve fibers innervating the neck and shoulder.
Year introduced: 2015
Brachial Plexus Block
A blocking of NEURAL CONDUCTION in the network of nerve fibers innervating the UPPER EXTREMITY.
Sphenopalatine Ganglion Block
Method of treating pain associated with the sphenopalatine ganglion located in the PTERYGOPALATINE FOSSA, posterior to the middle nasal turbinate. The transnasal approach involves application of suitable local anesthetic to the mucous membrane overlying the ganglion.
Year introduced: 2012
Sinoatrial Block
Disturbance in the atrial activation that is caused by transient failure of impulse conduction from the SINOATRIAL NODE to the HEART ATRIA. It is characterized by a delayed in heartbeat and pauses between P waves in an ELECTROCARDIOGRAM.
Year introduced: 1991(1975)
Nerve Block
Interruption of NEURAL CONDUCTION in peripheral nerves or nerve trunks by the injection of a local anesthetic agent (e.g., LIDOCAINE; PHENOL; BOTULINUM TOXINS) to manage or treat pain.
Year introduced: 1974
Congenital heart block [Supplementary Concept]
A congenital condition of unknown etiology. It may be associated with maternal AUTOIMMUNE DISEASE or viral infection during pregnancy. OMIM: 234700
Date introduced: August 25, 2010
Hereditary bundle branch system defect [Supplementary Concept]
A form of heart block caused by dominant mutations in the SCN5A gene and characterized by RIGHT BUNDLE-BRANCH BLOCK. OMIM: 113900
Date introduced: November 5, 2012
Volume Electron Microscopy
Electron microscopy techniques designed to reconstruct 3-D images at micrometer volume scales at nanometer (nm) level resolutions. Volume electron microscopy uses various techniques to render, segment and reconstruct 3-D images from stacked sequential 2-D images of incremental z-planes.
Year introduced: 2023
Delayed Emergence from Anesthesia
Abnormally slow pace of regaining CONSCIOUSNESS after general anesthesia (ANESTHESIA, GENERAL) usually given during surgical procedures. This condition is characterized by persistent somnolence.
Year introduced: 2009
oligo(trimethylene carbonate)-block-poly(ethylene glycol)-block-oligo(trimethylene carbonate) diacrylate [Supplementary Concept]
a photo-polymerizable precursor for the encapsulation of primary articular chondrocytes; structure in first source
Date introduced: February 18, 2012
polyethylene glycol-block-poly(lactic-co-glycolic-co-hydroxymethylglycolic acid) [Supplementary Concept]
used to form nanoparticles for protein delivery; structure in first source
Date introduced: June 16, 2015
Neuromuscular Blockade
The intentional interruption of transmission at the NEUROMUSCULAR JUNCTION by external agents, usually neuromuscular blocking agents. It is distinguished from NERVE BLOCK in which nerve conduction (NEURAL CONDUCTION) is interrupted rather than neuromuscular transmission. Neuromuscular blockade is commonly used to produce MUSCLE RELAXATION as an adjunct to anesthesia during surgery and other medical procedures. It is also often used as an experimental manipulation in basic research. It is not strictly speaking anesthesia but is grouped here with anesthetic techniques. The failure of neuromuscular transmission as a result of pathological processes is not included here.
Year introduced: 1997
PLC(20)-b-PEO(44) [Supplementary Concept]
block copolymer micelles
Date introduced: November 26, 1999
polyethylene oxide-polylactic acid block copolymer [Supplementary Concept]
structure given in first source
Date introduced: March 15, 1989
Brugada Syndrome
An autosomal dominant defect of cardiac conduction that is characterized by an abnormal ST-segment in leads V1-V3 on the ELECTROCARDIOGRAM resembling a right BUNDLE-BRANCH BLOCK; high risk of VENTRICULAR TACHYCARDIA; or VENTRICULAR FIBRILLATION; SYNCOPAL EPISODE; and possible sudden death. This syndrome is linked to mutations of gene encoding the cardiac SODIUM CHANNEL alpha subunit.
Year introduced: 2007