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(ā″spĕr″mat″ŏ-jen′ĕ-sĭs) [1an- + spermatogenesis] Absence of spermatogenesis.


(ā″spĕr′mē-ă) [1an- + sperm + -ia] Failure to form semen or to ejaculate. aspermic (-mik), adj.

aspheric, aspherical

(ā″sfēr′ik, ā″sfēr′ĭ-kăl) [1an- + spherical] In optometry, pert. to a lens that is not exactly spherical. Such lenses are used in eyeglasses because they are thinner and usually provide better vision than standard lenses.


(ăs-fik′sē-ă) [1an- + Gr. sphyxis, pulse] An insufficient intake of oxygen. asphyxial (-sē-ăl), adj.

 ETIOLOGY: Extrinsic causes include choking, toxic gases, exhaust gas (principally carbon monoxide), electric shock, drugs, anesthesia, trauma, crushing injuries of the chest, compression of the chest, injury of the respiratory nerves or centers, diminished environmental oxygenation, and drowning.

 Intrinsic causes include hemorrhage into the lungs or pleural cavity, foreign bodies in the throat, swelling of the airways, diseases of the airways, ruptured aneurysm or abscess, edema of the lung, cardiac deficiency, tumors such as goiter, and pharyngeal and retropharyngeal abscesses. Other causes include paralysis of the respiratory center or of respiratory muscles, anesthesia, pneumothorax, narcotic drugs, electrocution, and child abuse.

 SYMPTOMS: In general, symptoms range in severity from dyspnea, palpitations, and impairment of consciousness, to coma, seizures, permanent brain injury, and death.

autoerotic a. Autoerotic hypoxia.

fetal a. Asphyxia occurring in a fetus. It results from interference in placental circulation, umbilical cord compression, or premature separation of the placenta, as in abruptio placentae.

local a. Asphyxia affecting a limited portion of the body, e.g., fingers, hands, toes, or feet, due to insufficient blood supply. It is a symptom usually associated with Raynaud’s disease.

sexual a. Autoerotic hypoxia.


(ăs-fik′sē-ănt) An agent, esp. a gas, that produces asphyxia.

chemical a. An agent that prevents the delivery of oxygen from the bloodstream to cells, or that disables the biochemistry of cellular respiration even in the presence of adequate oxygen levels in the blood. Chemical asphyxiants include agents such as carbon monoxide and cyanide. Initial treatment consists of the administration of 100% oxygen along with an antidote (such as hydroxocobalamin, sodium nitrite, or sodium thiosulfate).

simple a. A gas that displaces oxygen from the atmosphere, thereby reducing the amount of oxygen available during inhalation.


(ăs-fik′sē-āt″) To cause asphyxiation or asphyxia. asphyxiation (-fik″sē-ā′shŏn), n. asphyxiator (-fik′sē-āt″ŏr), n.


(as′pĭ-rāt″) [L. aspirare, to blow, breathe upon] 1. To draw air or other matter in or out by suction. 2. To remove matter, e.g., ...

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