It is not necessary here to give directions for using the forceps in every variety of presentation and position, but simply to show the mode of applying them as they are most frequently required. The two blades are adjusted separately, one to each side of the head, and then locked together, so that the head is firmly inclosed between them, but not crushed. Dr. Denman gives perhaps the best and simplest directions on this point, and I therefore quote from his work.
"The first part of the operation consists in passing the forefinger of the right hand behind the ossa pubis and the head of the child to the ear; then taking the part of the forceps to be first introduced by the handle in the left hand, the point of the blade is to be slowly conducted between the head of the child and the finger till the instrument touches the ear: there can be no difficulty or hazard in carrying the instrument thus far, because it will be guided, and in some measure shielded, by the finger. But the further introduction must be made with a slow semi-rotatory motion, keeping the point of the blade not rigidly, yet closely, to the head of the child, by raising the handle toward the pubes. In this manner the blade must be carried gently along the head till the lock reaches the external parts near the anterior angle of the pudendum. The point of the blade, while introducing, sometimes hitches upon the ear of the child, and it then requires a little elevation. But when it has passed the ear, and is beyond the guidance of the finger, should there be any check to the introduction either of this or the other blade, it should be withdrawn a little, to give us an opportunity of discovering the cause of the obstacle, which we must never strive to overcome by violence, though we must proceed with firmness. When the first blade is properly introduced, it must be held steadily in its place by pressing the handle towards the pubes, and it will be a guide in the introduction and application of the second blade. Let the second blade be introduced in this manner. Keep the blade first introduced in its place with the two lesser fingers of the left hand, and carry the fore-finger of the same hand between the perineum and head of the child as high as you can reach. Then take the second blade of the forceps by the handle in the right hand, and, conveying the point between the finger placed within the perineum and the head of the child, conduct the instrument, with the precautions before mentioned, so far that the lock shall touch the interior part of the perineum, or even press it a little backwards. In order to fix the two blades thus introduced, that which was placed towards the pubes must be slowly withdrawn, and carried so far backwards that it can be locked with the second blade retained in its first position; and care must be taken that nothing be entangled in the lock, by passing the finger round it. When the forceps are locked, it will be convenient to tie the handles together with sufficient firmness to prevent them from sliding or changing their position when they are not held in the hand, but not in such a manner as to increase the compression upon the head of the child. Should the blades of the forceps be introduced so as not to be opposite each other, they could not be locked; or if, when applied, the handles should come close together, or be at a great distance from each other, they would probably slip, or there would be a failure of some kind in the operation, as the bulk of the head would not be included, or they would be fixed on some improper part of the head; though allowance is to be made for the difference in the size of the heads of children. But if a case be proper for the forceps, if they be well applied, and we were to act slowly with them, there would not be much risk of failure or disappointment. The difficulty of applying the forceps is most frequently occasioned by attempting to apply them too soon, or by passing them in a wrong direction, or by entangling the soft parts of the mother between the instrument and the head of the child, against all which accidents we are to be on our guard.
"When the forceps are first locked, they are placed backwards, with the lock close to, or just within, the internal surface of the perineum; and they can have no support backwards, except the little which is afforded by the soft parts. The first action with them should therefore be made by bringing the handles, grasped firmly in one or both hands, to prevent the instrument from playing upon the head of the child, slowly towards the pubes till they come to a full rest. Having waited a short interval with them in that situation, the handles must be carried back in the same slow but steady manner to the perineum, exerting, as they are carried in the different situations, a certain degree of extracting force; and after waiting another interval, they are again to be carried towards the pubes, according to the direction of the handles. Throughout the operation, especially the first part, the action of that blade of the forceps originally applied towards the pubes must be stronger and more extensive than the action with the other blade, this having no fulcrum to support it, and chiefly answering the purpose of regulating the action of the other blade. If there were any labor pains when the operation was begun, or should they come on in the course of it, the forceps should only be acted with during the continuance of the pains; the intention being, not only to supply the want or insufficiency of the pains, but to follow them, and imitate also the manner in which they return. By a few repetitions of this alternate action and rest before described, we shall soon be sensible of the descent of the head; and it will be proper to examine very frequently, to know the progress made, that we may not use more force than needful, nor go on with more haste than may be expedient or safe. In every case we ought to proceed slowly and circumspectly, not forgetting that a small degree of force, continued for a long time, will in general be equivalent to a greater force hastily exerted, and with infinitely less detriment to the mother or child. But after some time, should we not perceive the head to descend, the force hitherto used must be gradually increased, till it be sufficient to overcome the obstacles to the delivery of the patient. It was before observed, as the head of the child descended, that the face would be accordingly turned towards the hollow of the sacrum, without any aim or assistance on our part. Of course the position of the handles of the forceps, and the direction in which we ought to act with them, should alter; for they becoming first more diagonal or oblique with respect to the pelvis, and then more and more lateral, every change in their position will require a differently directed action, because the handles should ever be antagonists to each other. In proportion also to the descent of the head the handles of the forceps should approach nearer to the pubes; so that, in the beginning of the operation, though we acted in the direction of the cavity of the pelvis, towards the conclusion we should act in that of the vagina. When we feel that we have the command of the head, by its being cleared of the pelvis, and the external parts begin to be distended, we ought to act yet more slowly, especially in the case of a first child, or there would be great danger of a laceration of the soft parts; and this can only be prevented by acting very deliberately in the direction of the vagina—by giving the parts time to distend—by duly supporting the perineum, which is the part chiefly in danger, with the palm of the hand—by soothing and moderating the hurry and efforts of the patient—and, in some cases, by absolutely resisting for a certain time the passage of the head through the external parts."
PLATE LI.
The head being drawn through a narrow Pelvis by the Forceps.
The manner in which the forceps draw the head is well shown in the above plate, and also the compression of the head itself, which is seen to be squeezed almost to a point at its presenting part. This compression, however, is not likely to do serious injury, unless it be excessive. The child may be convulsed a little from it, but usually recovers, and suffers nothing afterwards.
It is merely necessary to remark, in conclusion, that the forceps should never be used till it is manifestly impossible for the child to be born without them; and it should be remembered that nature alone frequently effects delivery under the most unfavorable circumstances, by giving her time. We should wait therefore as long as the safety of the mother will allow, but never delay a moment when that safety is compromised.