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position statement

(stāt′mĕnt) The official, published editorial taken by a professional organization regarding best practices, standard care, or inconclusive evidence-based research. Position statements are typically updated regularly. SEE: consensus statement.


(poz′ĭt-iv) [L. positivus, settled by ruling or agreement] 1. Definite; affirmative. 2. Indicating an abnormal condition in examination and diagnosis. 3. Having a value greater than zero. In laboratory findings and mathematical expressions, positive is indicated by a plus (+) sign.

positive predictive value

SEE: under predictive value.


(pŏz′ĭ-trŏn) A particle having the same mass as a negative electron but possessing a positive charge.


(pō-sol′ŏ-jē) [Gr. posos, how much + -logy] In pharmacology, the determination of proper dosages, esp. of the beneficial or adverse effects of drugs administered at specific doses. It includes the study of errors made in calculating the doses of medications given to patients. posologic, posological (pō″sŏ-loj′ik, pō″sŏ-loj′ĭ-kăl), adj.


In dentistry, a cast restoration that extends into the root of a tooth to anchor a dental crown or prosthesis.


[L. post, after, behind] A prefix meaning behind, after, posterior.


(pōst″ă-bor′tăl) [L. post, behind, after, + abortus, abortion] Happening subsequent to abortion.


(pōst″ad-ŏ-les′ĕnt) [post- + adolescent] Pert. to the period between adolescence and adulthood. One who is passing between adolescence and adulthood. postadolescence (pōst″ad-ŏ-les′ĕns), n.

post-anesthesia care unit

ABBR: PACU. A unit to which patients are admitted after surgery for the monitoring of signs and symptoms that suggest that they may have poorly tolerated their anesthesia or operation. The typical PACU is staffed by nurses who evaluate patients for symptoms of instability (such as bleeding, chest pain, or labored breathing), or unstable vital signs (such as, excessive pain, low blood pressure, poor oxygenation, or tachycardia). Anesthesiologists, hospitalists, and/or surgeons may be available for consultation or the management of emergencies.


(pōst″an-ĕs-thet′ik) [post- + anesthetic] Pert. to the period following anesthesia.


(pōst″bī-ot′ik) [post- + biotic ] 1. Pert. to an extract of probiotic bacteria (or their metabolic byproducts). 2. A postbiotic substance. SEE: probiotic.

postcardiac arrest syndrome

Neurological impairment, myocardial stunning, internal organ injury, and systemic inflammation resulting from inadequate blood flow to vital organs during cardiac arrest. The syndrome may be attenuated by targeted lowering of body temperature, mechanical ventilation, circulatory support, and keeping ...

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