A synoptical guide to the study of obstetrics : being an aid to the student in the class-room, in private study and in preparing for examinations / by Robert Barnes.

Date:
1883
Catalogue details

Licence: Public Domain Mark

Credit: A synoptical guide to the study of obstetrics : being an aid to the student in the class-room, in private study and in preparing for examinations / by Robert Barnes. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    26/140 (page 14)
    Rotation-movements to one-quarter of a circle take place to right or left on atloi'do-axial articulation. Rotation to extent that face looks directly back may be produced without lesion (Tarnier). Doubtful (Ramsbotham; R. B.). Dimensions of trunk.—Diameters: (1) Bis-acromial, or transverse ; (2) antero-posterior, or sterno-dorsal. Transverse, capable of great reduction under pressure. General rule : Where the head can pass, the shoulders and trunk rarely fail to pass easily. Three diameters of pelvis: (1) Transverse, bis-iliac; (2) antero-posterior pubio-sacral •, (3) bi-trochanteric. Pelvic diameters of foetus may be increased by legs flexed upon body, but the cone so formed may be decomposed by bringing down legs in extension. The diameters of the trunk are all smaller and more re- ducible than those of head. The antero-posterior diameters of the trunk are shorter than the transverse, the opposite to what obtains in the head Hence the rotation-movement of trunk during expulsion. (The measurements of head given under Labour, see p. 49.) FUNCTION'S OF THE FOETUS. Circulation ; Respiration ; Nutrition ; Secretions ; Innervation. A. Circulation.—First circulation, circulation of the umbilical vesicle, or omphalo-mesenteric circulation; second circulation, or placental; third, at birth the placental circulation is transformed into pulmonary. 1. In embryo, heart forms two ventricles, two auricles, these communicating by foramen Botallii. Arterial system : aorta formed later, external iliacs give off umbilical arteries; other arteries, systemic, are developed. Venous system : from allantoid vesicle run two veins, the umbilical allantoid or placental veins. One vein atrophies, the other becomes