#circulation

• ABC (Airway, Breathing, Circulation) — A fundamental medical acronym used in cardiopulmonary resuscitation (CPR) and first aid protocols, standing for the critical steps of primary assessment and intervention: A (Airway), B (Breathing), and C (Circulation). While modern cardiac arrest guidelines often use the CAB sequence, ABC remains the cornerstone for primary trauma assessment.
• Acrocyanosis — A chronic, painless peripheral circulatory disorder characterized by a persistent bluish or livid discoloration of the body's extremities, accompanied by cold sweat and local hypothermia.
• Acroerythrosis — A peripheral circulatory disorder characterized by a persistent, intense, and often symmetrical reddish or purplish discoloration of the extremities (hands, feet, digits), caused by capillary dilation.
• Ventilation — The act of airing out a space and its result; a controlled or natural process through which stale air from an enclosure is replaced with fresh outdoor air. In a technical sense, it represents a structural opening, a channel, or a specially designed device (grille, valve) that allows gas circulation, component ventilation, or the bleeding of air bubbles from a hydraulic circuit.
• An-Nafis — The name of the famous Arab scientist, physician, and polymath Ibn an-Nafis (1213–1288), historically known as the first person to correctly describe the pulmonary circulation of blood. His pioneering works in anatomy and physiology anticipated the discoveries of modern European medicine by several centuries, representing a central figure of the Islamic Golden Age.
• Angiocheiloscope — A specialized optical device or medical apparatus used in stomatology, dermatology, and microcirculation for the direct, magnified, and structural examination of the capillary vessels within the lips. This niche instrument integrates advanced cold lighting systems and microscopic lenses, allowing clinicians to analyze circulatory flow, vascular wall modifications, and capillary architecture in various systemic pathologies.
• Angiocheiloscopy — A non-invasive clinical investigation method consisting of the microscopic examination and structural recording of the capillary network within the lips. This specialized procedure allows physicians to analyze in real time microvascular blood flow velocity, lumen diameter, and potential structural architectural deformations associated with systemic pathologies such as scleroderma, vasculitis, or diabetes mellitus.
• Angiomicrocinematography — A highly specialized medical investigation method consisting of high-speed cinematographic or video recording, through a microscope, of blood circulation within capillary vessels and arterioles. This structural process allows the well-defined analysis of microvascular flow dynamics, red blood cell deformability, and leukocyte-endothelium interactions in various experimental models or systemic clinical pathologies.
• Angiotrophoneurosis — A complex structural pathological state from the group of acroanesthesias and peripheral vasomotor disorders, characterized by the well-defined association of chronic spasms or vasodilations of small blood vessels with severe trophic changes in the innervated tissues. This process, caused by an abnormal excitability or functional degeneration of the neurovegetative nervous system, manifests clinically through paroxysmal painful episodes, cutaneous ulcerations, circumscribed edemas, and marked changes in the skin color of the extremities, as observed in Raynaud's disease or acrocyanosis.
• Anisoscillometry — A clinical medical investigation method consisting of measuring and comparatively analyzing the oscillometric index or arterial pulsation amplitude between two symmetrical regions of the body (typically between the left and right limbs). This diagnostic technique is used to detect circulatory asymmetries, segmental vascular obstructions, or obliterating arteriopathies by highlighting discrepancies in pulsatile volume.
• Arteriole — A microscopic blood vessel, with a diameter under 100 micrometers, structurally located between the terminal ends of large arteries and the capillary network. Due to the well-developed smooth muscle layer within their walls, arterioles act as the primary resistance vessels of the circulatory system, playing a fundamental role in regulating blood pressure and regional blood flow distribution through vasoconstriction and vasodilation.
• Arteriolar — Belonging to the arterioles, relating to the arterioles, or occurring at the level of these microscopic blood vessels that structurally connect arteries to the capillary network; describes microvascular elements directly involved in regulating total peripheral resistance and systemic arterial pressure through vasoconstriction and vasodilation processes.