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position of the child's head must govern us in their application, whether it offers at the brim or has descended into the pelvic cavity, or when it has reached the inferior strait; that is, they must be placed on the sides of the head, and the only deviation from the arbitrary rule is when the sagittal suture lies in the transverse position.
I must confess that I cannot see the logic of such reasoning, for when the head is lying in either of the oblique diameters of the pelvis, and the forceps are applied so as to lie in the opposite diameter, the convex edges of the blades do not correspond to the curve of the sacrum. When applied in the right oblique or first position, we will find, on examination, that the convexity of the posterior blade will point towards the right quarter of the sacrum, whilst the anterior one will be in relation to that portion of the ilium midway between the posterior border of the obturator foramen and the anterior aspect of the great sciatic notch. In other words, the convex edges of the blades will look towards the right posterior quarter of the pelvis, and not directly towards the sacrum.
Let me not be misunderstood. I do not for a moment assert that the addition of the sacral curve is superfluous, but I do hold that it simply allows of their more perfect adjustment at or above the brim.
Let me ask the question : “When delivery is to be effected by instrumental aid, is direct traction the only object to be attained ?” I shall endeavor to prove that another and a most important factor must be used as an auxiliary in order to intelligently direct the force under our command.
Dr. Barnes, in his work on operative midwifery, positively asserts that direct traction is almost impossible, and advises traction combined with the lateral swaying leverage, or what has been termed the pendulum motion. The latter method of delivery has been recommended by very high authority, whilst it has been rejected by others as worthless and positively injurious.
In an excellent monograph by Professor Landis, of Starling College, Ohio, on “How to Use the Forceps,” the propriety of using this lateral leverage is fully discussed and absolutely condemned.
We should lay it down as a cardinal principle that in artificial delivery the more closely we follow the process of natural labor the more successful will be our efforts, and the less danger will be incurred by the mother and child. The mechanism of labor is a complex movement, and in vertex presentations is usually divided into five stages : Flexion, descent, rotation, extension, and restitution. There is another and a very important motion imparted to the head, which, although recognized by authors in their description of labor, is strangely overlooked when laying down rules for the proper application of the forceps.
After the stage of flexion takes place, the head is usually described as descending into the pelvic cavity, rotation following as it passes into the pelvic excavation.
As the pelvis is a curved canal with the greater curvature posteriorly, the head in its descent travels, as it were, on a pivot, the symphysis pubis being the point around which it moves, producing what may be termed sacro-coccygeal rotation. In order to explain my meaning more clearly, I shall take the liberty of quoting from Cazeaux's description of the mechanism of labor in the presentation of the vertex in the first position :
“The descent of the head is not completed until the occipitobregmatic circumference is nearly parallel to the plane of the inferior strait. Now, it is evident that to reach this point the left parietal boss (which is found behind) must traverse the whole anterior face of the sacrum, whilst the anterior one has only to clear a much shorter space. Perhaps a more exact idea of the actual movement of the head will be found by imagining the anterior extremity of the bi-parietal diameter to remain almost stationary in front and to the right, whilst its posterior extremity descends rapidly, and traverses the whole posterior plane of the excavation.”
We can now perceive that with the long double-curved forceps, even though we were enabled from their construction to make traction in the axis of the superior strait, our exertions would be entirely directed toward bringing the head down into the pelvic cavity at the original plane it held after the commencement of labor-a most unscientific and unnatural operation to say the least. How much injurious pressure is thrown against the symphysis pubis and bladder in a difficult case of forceps delivery from failing to take advantage of the lesson taught us by nature, how much misery is entailed on the mother as a legacy by the powerful and misguided efforts of the operator, will never be revealed. There are few of us who have had much experience in midwifery who cannot recall many instances of permanent injury inflicted by the ignorant, and I may add almost criminal, use of the forceps.
Have we any means within our power of using the forceps so as to cause the head to move in a manner similar to that produced by uterine contraction ?
I answer, yes.
Among the many plans proposed, I may mention that of Dr. A. H. Smith, of Philadelphia, who directs the palmar surface of the left hand to be placed over the lock of the instrument; the fingers are then passed as high as possible until they touch the head, when pressure is directed backwards and downwards, the handles at the same time are pulled forward and upward. Dr. Landis recommends a somewhat similar maneuvre, by carrying the index finger of the left hand along the upper arm of one blade and the middle finger upon the other; a most excellent method in cases where the delay is caused by uterine inertia, but in cases of dystocia from a contracted pelvis would, I am confident, prove entirely inadequate.
The instrument I present before you is the ordinary Elliott forceps. On the upper arm of right-hand blade is attached a grooved piece of steel, a little over two inches in length, terminating in a countersunk extremity. Into this I have fitted a slightly curved rod, with a rounded end very much flattened on the sides. The blades of the forceps are three-sixteenths of an inch narrower across the concave edges than from similar points posteriorly.
The manner of using them may be described in a few words. After the forceps are locked, the end of the rod is held edgewise and passed along the groove prepared for it, until the countersunk cup at the extremity is reached. The rod is then given a quarter turn, when it immediately forms a ball and socket joint, and cannot be withdrawn without reversing the motion. The handles of the forceps are now carried down, so as to press slightly against the perineum, and the rod elevated to an angle of about ninety degrees; the elevation, of course, varying according to the situation of the head.
Press downwards and backwards with the rod at the same moment you make counter force upwards and forwards on the handles of the forceps. As the head is found to descend into the excavation, the line of pressure on the rod must be changed to downwards and slightly backwards until the inferior strait is reached, when the rod may be detached and the delivery completed as with the ordinary forceps.
The object of the operation, you may observe, is to depress the distal ends of the blades, and with them that portion of the head which lies posteriorly, sweeping it rapidly over the face of the sacrum, whilst the anterior part is held almost stationary at the symphysis pubis, producing what I have already described as sacro-coccygeal rotation.
When the instrument is used as a fulcrum forceps, it is absolutely necessary to apply them as nearly as possible to the sides of the pelvis. The reason becomes evident on reflection. If applied in relation to the child's head in either of the first two positions, there is great danger of causing forced extension and converting a vertex into a face presentation. If you bear in mind that when the occiput presents anteriorly in the oblique diameter, the forehead will be found at the opposite ilio synchondrosis, and from the peculiar action of the instrument the position of the occiput would remain unchanged whilst the forehead underwent forcible depression.
This fact, indeed, might be taken advantage of in mento-posterior presentations of the face by placing the woman with her chest and abdomen on the bed, then introducing the blades on the sides of the child's face with their concave edges locking posteriorly. If we now lift the face above the superior strait, making pressure on the blades in the manner already described, the tendency will be to cause forcible flexion of the chin on the chest, whilst the forehead is at first depressed and if the leverage is persisted in, the occiput will be found to descend, thus converting a mento-posterior into an occipito-anterior position. This is, however, only theoretical, and would need practical experience in order to prove its feasibility. It is a suggestion I think worthy of trial for the purpose of remedying one of the most difficult presentations of the fætus.
In a case which I was recently called to deliver, I had an excellent opportunity of testing its powers. The woman, a multipara, had been in labor about thirty-six hours. The membranes having ruptured early, the first stage was protracted, owing to a rigid condition of the os. I administered morphine followed by twenty gr. doses of chloral, repeated several times without much effect in producing dilatation. I then followed a plan I have many times resorted to in cases of tedious labor from partial inertia and rigidity of the os. I ordered an ounce of castor oil. This, in my opinion, has a threefold action. It produces nausea, followed by relaxation of the muscular tension of the cervix, empties the rectum, and by its effects on the latter causes reflex contraction of the abdominal muscles, which I am inclined to think is also participated in by the uterus. I have so many times seen labor induced by a large dose of castor oil in women who have almost completed the period of gestation that I cannot help ascribing these properties to it.
The head having failed to pass the brim, owing to a conjugate contraction, I applied the forceps, and with but slight exertion compared to what I would have had to use with the ordinary instrument, I succeeded in delivering a living child. That no injury was inflicted on the mother was evident from the fact that she passed water without pain, whilst after her previous continement, when instruments were employed, the catheter had to be used for a number of days.
One objection has been raised against the use of the rod, —that sufficient power cannot be brought to bear with one hand only on the handles of the forceps. This, indeed, would constitute a very serious drawback if we were compelled to use such powerful traction as we sometimes see mentioned by medical writers, when two physicians are described as pulling on the forceps at the same time, and bracing their feet against the bedstead in order to obtain a firmer purchase. We should not forget, however, that much of this great force is lost, as it is directed in an improper direction. A far less expenditure of strength, judiciously exerted and scientifically employed, would prove much more effectual. I can assert, from practical experience, that in cases where the contraction is not too great, owing to the action cf the instrument as a lever and the rod as a fulcrum, that sufficient force can be produced to accomplish delivery with safety and ease.