We will now proceed to define the limitations of the different procedures called for in pelvic narrowing, bases upon comparative degrees of deformity expressed in inches at the conjugate of the superior strait.
It is obviously impossible to construct rigid absolute rules for the guidance of the surgeon in cases of this kind. Other factors besides that of pelvic contraction have to be taken into consideration, and herein the personal equation, i.e., the skill and experience of the operator are of great value in deciding in favor of one procedure or another.
The variety of the deformity, as well as the degree of contraction in both transverse and conjugate diameters, the depth of the symphysis and angle of inclination, the size of the foetal head, the condition of the child, and duration of labor are all factors of such great importance that neither one can be neglected in the estimate of the procedure which it is desirable to adopt to effect delivery. In a Society discussion, or in a formal essay, we can venture to split hairs, and declare that this or that operation is the suitable one in a certain variety of deformity, with contraction not exceeding a certain degree. But at the beside all this is changed. It is results that we are anxious to obtain-to save both lives, if possible, which, considering the means at our command at the present day, we are not to be excused if we fail in securing.
The only hope we have of ever being able to accomplish such results is to study our cases in advance. Since it is practically impossible for two men to agree regarding the exact length of the true conjugate, how are we to be guided by a difference of 1/4 of an inch, as to whether we shall elect forceps, version, craniotomy, symphyseotomy, or the Caesarean section. These are the most difficult problems that can ever be placed before any man, and only the highest judgment, based on the most through examination, under the most favorable conditions, can hope for a satisfactory answer to these questions.
4. Can we define, with any degree of certainty, the limitations of the different operations procedures by an approximate estimate of the external of the narrowing?.
Under this head we have, as elective operations, forceps, version, symphyseotomy, craniotomy, and celiotomy of Caesarean section. The answer to the above questions may be stated in five propositions.
1. These cases in which the deformity is limited to a shortening of the conjugate at the brim, and does not exceed 3 1/2 inches. In simple flat pelvis contraction of the conjugate to this extent may terminate in normal labor, or forceps or version may be the operations of election. When all the diameters are reduced to the length of the conjugate, as in the justo-minor pelvis, four inches at the latter point may give rise to considerable delay in delivery and require forceps, though a natural birth of a living child at term is probable. A conjugate of four inches in the generally contracted flat pelvis may also cause difficulty in the birth and require forceps or version.
2. Those cases in which the diminution of the conjugate is reduced from 3 3/4 inches to 3 1/4 inches, though a normal labor is not impossible with a conjugate of 3 3/4 inches. In the simple flat pelvis version is likely to be required. Playfair says forceps are applicable in all degrees of contraction down to 3 1/4 inches conjugate of brim, though version is preferable when contraction is chiefly in the anterior-posterior diameter, with abundance of room at the sides of the pelvis for the occiput to occupy after the version.
Many obstetricians believe that it is possible to deliver a living child by turning in a pelvis contracted to the extent of 2 3/4 inches in the conjugate diameter. Playfair inclines to this belief. Barnes maintains that, although an usually compressible head may be drawn through a pelvis contracted to 3 inches, the chance of the child being born alive under such circumstances must necessarily be small, and that from 3 1/4 inches to the normal size must be taken as the proper limits of the operation of version.
A justo minor pelvis with a conjugate of 3 3/4 inches may be terminated by forceps. Version is absolutely contraindicated in pronounced cases of this variety (3 1/2 inches to 3 inches). If such a case is seen in time, the induction of premature labor, after viability, is preferable to forceps or version at full term. Should labor have begun, the case may be allowed to progress until nature has shown her inability to cope with the emergency. Then forceps, or, later, symphyseotomy, or, if the child be dead, craniotomy, may be necessary.
3. In all cases, without regard to the kind of deformity, if the birth canal is not obstructed by tumors, cicatrices or other insurmountable obstacles to delivery, when the conjugate of the inlet is reduced from 3 1/2 inches (8 c.m.) to 2 5/8 inches (6 6/10 cm.), symphyseotomy seems, according to the latest reports, to be the operation which offers the best chances to mother and child. The object of separating the pubic symphysis (pubiotomy or symphyseotomy) is to increase, by the artificial separation of this joint, the dimensions of the birth canal.
Quoting form a recent article by Dr. H.J. Garrigues, he says, [Medical Record, May 20, 1893, p. 611.] “If the symphysis pubis is cut in a woman lying on her back, with outstretched legs, the ends of the bones separate very little-only about half an inch;l but if the joints of the hips and knees are bent, the distance is 1 1/4 to 1 1/2 inches, and by pulling on the iliac bones this is easily increased to 2 1/4 inches, and without injury to the sacro-iliac articulations; but if the separation is carried as far as 3 1/2 to 4 inches, one or both of these joints are torn open.
“In consequence of the separation of the public bones, a considerable change takes place in all directions of the pelvis, whereby it is rendered much more spacious in all directions or planes supposed to be laid at right angles through the axis”.
As a result of the advantage gained by the increase in the dimensions of the pelvis by the performance of symphyseotomy, the prospect is that craniotomy on the living child will be banished from obstetrical practice. If certainly will be so in hospital practice, and it should and will be so in private practice if obstetricians make themselves familiar with the rationale of the procedure and recognize the advantages to be derived from its adoption.
4. In a contraction of the pelvis less than 2 3/4 inches (2 5/8 inches, or 6 6/10 c.m.) and not exceeding 2 1/2 inches (6 4/10 c.m.), the operation for the induction of premature labor soon after the thirtieth week is the operation which may be considered, and, like the operation for the induction of abortion in the highest degree of pelvic contraction, is to be compared and comes into competition with the modern operation of Caesarean section. Until recently, contractions less than 2 3/4 inches in the justo-minor pelvis and of less than 2 1/2 inches in the simple flat pelvis, placed these cases under the ban of that sacrificial procedure-abortion.
At the present time the new Caesarean section, by means of a more perfect technique, asepsis, and the more perfect diagnosis of the conditions demanding operation, offers to the patient a procedure which is greatly to be preferred, in view of its life-saving features to both mother and child. Abortion may be avoided and premature labor is unnecessary. Caesarean section seems absolutely indicated in any pelvis whose diameters are below 2 5/8 inches conjugate vera, with a living child; also in cancer of the cervix, in oblique deformities of the pelvis, and when tumors obstruct the vagina, so as to render the birth of a living child impossible.
5. Craniotomy, since the revival of the operation of symphyseotomy, has a very much more limited field of applicability than formerly, if recent impressions prove to be reliable.
Upon the dead foetus it is certainly justifiable in moderate degrees of pelvic contraction, in malpresentations and positions, deformities of the foetus, and in cases when the conjugate vera is under 2 3/4 inches.
Whether craniotomy upon the living foetus is ever justifiable is a question which men of large experience are not agreed upon. There with probably always be cases in which it is the only practicable resource left open to the operator. As, for instance, in a case of impacted occipito-posterior presentation, or a mento-posterior face presentation when the mother’s condition, as indicated by the temperature, pulse, loss of strength from the fruitless and prolonged efforts at delivery, associated with dangerous thinning of the lower uterine segment, is such as to make any operative procedure dangerous except that which enables us to deliver by the speediest and safest means possible-viz., craniotomy.
