PRIMIGRAVID LABOR - A GRAPHICOSTATISTICAL ANALYSIS
PRIMIGRAVID LABOR - A GRAPHICOSTATISTICAL ANALYSIS
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DOI:
10.1097/00006250-195512000-00001
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发表时间:
1955-01-01
影响因子:
7.2
通讯作者:
FRIEDMAN, EA
中科院分区:
文献类型:
--
作者:
FRIEDMAN, EA
This article describes the graphic portrayal of the course of first-stage labor, in which cervical dilatation is plotted against elapsed time from the onset of regular contractions. The study population included 500 primigravid parturients with detailed, accurate, and complete records, from the Sloane Hospital for Women of Columbia-Presbyterian Medical Center in New York City. Cervical dilatation estimated on rectal or vaginal examination was plotted on the ordinate and hours of elapsed time on the abscissa of square-ruled graph paper, producing an asymmetric sigmoid curve composed of two main phases, latent (from labor onset to the point at which the rate of dilatation begins to change) and active (from that point until complete dilatation). The calculated means were 8.6 and 4.9 hours for latent and active phases, respectively, with the “statistical maximums”(mean plus two standard deviations) 20.6 and 11.7 hours. The active phase consisted of three subdivisions, of which the most important, the maximum slope, averaged 3 cm per hour, with a normal minimum (95th percentile) of 1.2 cm per hour. The most common associations with prolongation of the latent and active phases were an unripe cervix and fetopelvic disproportion, respectively; excessive doses of sedative or analgesic medication appeared to prolong both phases, but the latent phase was particularly sensitive to the effect. Caudal anesthesia, administered after the active phase is clearly established, did not seem to alter normal labor. The effect of membrane rupture on the course of labor depended on timing; amniotomy during latent phase led to its lengthening (11.5 versus 10.5 hours,“borderline significance”). Friedman may not have really discovered anything new about the course of labor, for midwives and accoucheurs had undoubtedly long appreciated that cervical dilatation begins slowly and then at some point proceeds more rapidly. What Friedman did was define labor in a way that lent itself to quantitation and thus to standardization. It would prove enormously influential in several separate but related ways. First of all, it introduced terminology that was descriptive and understandable in place of that reflecting the presumed mechanism (“primary and secondary uterine inertia”). Second, it defined the components of labor and facilitated precise mathematical derivation of normative data for each phase. Third, it led to recognition that aberrations of different phases have different causes and widely varying prognoses, as Friedman would show in a series of reports over the next decade or two, most of them published in the Green Journal. Finally, the graphic approach proved to be a superb teaching device simply because it permits the course of labor to be comprehended literally at a glance. The “Friedman curve” or some variation thereof would be incorporated into labor room records, and generations of American medical students would find it invaluable in demystifying labor’s arcana. Elsewhere in the world, especially in Britain and its Commonwealth, it would be called the “partogram” and the starting point might be modified, but the basic idea was that put forth by Friedman in this 1955 article. Emmanuel Friedman was born, reared, and educated in New York. He took the MD (1951) and ScD (1959) degrees from Columbia University and was a house officer and junior faculty member there as well. In 1963 he was appointed department chair at Chicago Medical School, moving in 1969 to Boston, where he was chief of the service at Beth Israel Hospital and a professor in Harvard Medical School. Retiring in 1990 to New York City, he continues to indulge a lifelong devotion to opera, especially …