. An American text-book of obstetrics. For practitioners and students. nds ; the interval is about thirtyminutes at first, whereas at the end of labor it is but two to three minutes, andnearly disappears as the head emerges. Symmetrical pains often occur ingroups, followed by shorter or almost abortive pains. As to the force exerted,the pressure during the height of a pain never exceeds 100 millimeters (4inches) of mercury, the average being 60 millimeters (2f inches; Schatz).Leaman measured the force with which the head advanced (not the force withwhich it was propelled), and found a high pre
. An American text-book of obstetrics. For practitioners and students. nds ; the interval is about thirtyminutes at first, whereas at the end of labor it is but two to three minutes, andnearly disappears as the head emerges. Symmetrical pains often occur ingroups, followed by shorter or almost abortive pains. As to the force exerted,the pressure during the height of a pain never exceeds 100 millimeters (4inches) of mercury, the average being 60 millimeters (2f inches; Schatz).Leaman measured the force with which the head advanced (not the force withwhich it was propelled), and found a high pressure to be five pounds. Forcepswas required where it did not exceed two and a half The force ofthe pain remains about the same during the entire labor, or it may increase bya fourth, and this with no regard to weariness on the part of the patient. Theforce does not increase with the resistance offered, but the pains simply becomemore frequent and last longer. The type of the pains is nearly constant in thesame patient (Schatz). THE PHYSIOLOGY OF LABOR. 323. Fig. 166.—Palpation of the cervix before la-bor. The two rings are shown, with the finger-tiptouching what may be called clinically the in-ternal os (one-half natural size). The amount of force exerted by the pains is supposed to range between seven-teen and eighty pounds. Our methods of measuring, however, are and Poppel, who studied theforce required -to rupture the mem-branes, found that in easy cases it washardly more than the weight of thechild, and only in severe cases did itrise to fifty pounds. Sehatz7 passed arubber bag into the uterus during laborand connected it with a gauge, register-ing fifty-five pounds as the obstetrician knows that all the mus-cular power he possesses is sometimesinsufficient to prevent rapid expulsionof the head. The changes in shape in the uterusduring contraction are marked. In thequiescent state it rests against the spinalcolumn, ovoid in shape, the
Size: 1424px × 1754px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectobstetrics, bookyear1
