Original Contribution

SOME POINTS ON THE CAUSES AND MANAGEMENT OF DIFFICULT LABOR*

J. A. KINNEAR, M.D., TORONTO.

As "Difficult Labor" is a large and important subject and the causes very numerous, the time at my disposal for this paper compels me simply to touch on some points that have impressed me as being instrumental in causing difficult and delayed labor.

The most common cause of this condition is some degree of pelvic contraction at the brim. This pelvic contraction prevents the head engaging in the brim and hence the many malpresentations of the child, all of which cause more or less difficulty.

The first malpresentation I wish to mention is that of the occipito posterior. This is the most common cause of delayed labor. I have noticed in the cases where I have had to do a manual rotation of the occiput to the front that the promontory of the sacrum projected farther forward than normal, and I am satisfied that this projection of the promontory is the usual cause of this presentation. This projection interferes with the proper flexion of the head. As the head does not fit accurately into the brim of the pelvis, the membranes rupture early, and so with early rupture of the membranes and imperfect flexion of the head, the head does not mould into the pelvis the same as when well flexed, the result is very slow dilatation of the cervix, and hence the first stage of labor is unduly prolonged. If the promontory of the sacrum projects too far forward the head will not engage in the brim, the membranes will rupture early and there will be nothing to dilate the cervix and these patients go for days in labor, with a partially dilated cervix.

I saw a patient last week who had been in labor a week, R.O.P. position, membranes ruptured several days and still *Read before Section of Obstetrics and Gynecology, Academy of Medicine, Nov. 1, 1923.

the cervical dilatation only the size of a twenty-five cent piece. The child was dead, so I did a manual dilatation and delivered the child with difficulty. The more of this type of case I see, the more convinced am I that the proper treatment is early Cesarean section. I refer to the type where the head sticks at the brim and the cervix will not dilate. I would advise Cesarean section even when the membranes had been ruptured and the patient some time in labor so long as the child was all right and no attempts had been made at delivery. Of course the longer a patient has been in labor with ruptured membranes, the greater is the maternal risk.

When the head does engage in the pelvis, occipito posterior and the membranes have ruptured early, a caput succedaneum forms in the scalp and this dilates the cervix, although it may be slow.

As the first stage of labor is slow, the patient soon becomes. tired of these nagging pains that are accomplishing very little, and in this type of case I get the greatest benefit from morphine and hyoscine. Give morphine gr. 1/4, hyoscine hydrobromide B & W. 1/130 gr. (ampoule). This takes about one hour to take full effect. This relaxes the cervix and it dilates more readily. She sleeps deeply between the pains, during a pain she talks incoherently, is restless so that she requires a nurse to watch her, but she remembers nothing about it afterwards. If in three or four hours the cervix is not fully dilated and the drug is losing its effect, I would give 1/260 gr. hyoscine. In this way you control the patient until the cervix is fully dilated.

The second stage of labor is likely to be prolonged, owing to the long internal rotation of the occiput to the front on the pelvic floor. The fetal mortality is high, owing to the disturbance to the fetal circulation by the long second stage of labor. Watch the condition of the child during labor, although this is not easy because the back is posterior and it is not easy to hear the fetal heart sounds for that reason. If meconium appears in the show that is an indication of fetal asphyxia and the child should be delivered as soon as possible.

The mother should be watched for signs of exhaustion, as is shown by the temperature and pulse going up. If she is not making progress in the second stage, give her an anesthetic to the surgical degree, place her across the bed in the lithotomy position, insert the hand up past the head under the posterior shoulder, and with this hand under the shoulder and the

other hand on the abdomen, rotate the back of the child to the front, hold it there with the outer hand while you seize the head with the internal hand and rotate the occiput to the front, then apply the forceps with the hand still holding the head, otherwise it may go back to its old posterior position. The longer the patent is in the second stage the more difficult it is to do this rotation. If the head is low down on the perineum persistently, occipito posterior, and you cannot rotate it, apply the forceps with the occiput posterior and deliver in that position, although you may have to pull hard and get a nasty laceration. I have noticed that where a woman has had an occipito posterior in one labor she usually has the same condition in subsequent labors.

The next malpresentation I would like to mention is the face presentation. Before labor commenced it was probably a vertex presentation, but something, usually a small pelvic brim, interfered with the flexion of the head with the result that it gradually extended into a face. I had recently a good example of this. At the beginning of labor it was a L.O.A. position, but head not engaged. I examined her a little later and found the cervix dilated the size of a fifty-cent piece and the brow presenting. A few hours later the cervix was fully dilated and it was now a R.M.P. position. This presentation then is usually due to the pelvic contraction at the brim. Fortunately the majority of these cases deliver themselves if left to nature. The head engaging when the head is well extended and when the chin reaches the pelvic floor it rotates to the front and then the head is born by flexion. The labor, however, is likely to be slow, both in the first stage and second stage, as in the occipito posterior position and for the same reasons and the treatment should be the same. If the face will not descend into the pelvis after extension of the head, we must do either an internal version or Cesarean section. If she is a primiparous patient I would advise a Cesarean section. If she is a multiparous patient, so that the pelvic floor has been previously stretched and there seems to be sufficient room at the brim to deliver the head, I would advise an internal version. If the head sinks down into the pelvis mento posterior and sticks there, the chin remaining posterior, the treatment is the same as for a persistent occipito posterior, viz.: rotate the chin to the front by seizing the head between the fingers and thumb and twisting the chin to the front through three-eighths of a circle, then apply the forceps and deliver. It is useless to apply the for

ceps with the chin posterior, as you cannot deliver the head in that position. If you cannot rotate the chin to the front, it may be due to the fact that the head is not low enough in the pelvis, but is still in the pelvic brim, then I would try shoving up the head out of the pelvis and doing an internal version. If you cannot do either a rotation or version, because the head is jammed down so tight into the pelvis, I would do a craniotomy. As you are likely to get a nasty tear, probably into the rectum, if she is a primipara, I would advise doing a double episiotomy, that is, incise the vulva on each side, that will enlarge the vulvar orifice and prevent a rectal tear.

Next, the breech presentation-The management of the breech presentation, as in the previous malpresentations, may be quite easy, the patient making good progress throughout labor and eventually delivering herself without difficulty, but, on the other hand, it may be most tedious and difficult and end in disaster especially for the child. The place of greatest difficulty is where the breech will not engage in the brim of the pelvis. In this case the membranes are likely to rupture early and the cervix will only partially dilate. If a primipara with large child and perhaps small pelvis, I would advise Cesarean section. If a multipara, and I think sufficient room in the pelvis to deliver the child, I would bring down the legs and complete the delivery. I have not had much success with bringing down a leg and leaving the case to nature.

If it is an impacted breech, that is, the breech has engaged in the pelvis and sunk down to the pelvic floor but sticks there making no further progress, this is usually due to a Frank breech, that is, the legs are straight up on the abdomen of the child with feet at the shoulders instead of being flexed in tailor fashion on lower part of the abdomen. These straight legs act as splints, thus preventing lateri-flexion of the back, and if the back cannot flex laterally the breech cannot be born. The treatment here is to pass the hand along each leg to the knee, press out and back on the knee, thus flexing the hamstring muscles, seize the foot with the forefinger and bring it down and out. Do the same with the other leg. Now deliver as an ordinary breech, namely: See that the cord is pulsating and not pressed on, keep her across the bed in the lithotomy position, let her come out of the anesthetic, when pains have returned and breech about to be born, give pituitary ext. 1/2 C.C. to cause frequent and strong uterine contractions, place a warm towel around the buttocks to prevent respirations commencing, have

the anesthetist press on the uterus when the buttocks are born and during a pain he should shove the child out as far as the head. This will prevent the arms becoming extended past the head. Now with two fingers in the mouth to flex the head and two fingers of the other hand around the neck and over the shoulder, you make traction upward and forward and extract the after-coming head.

The last cause of difficult labor I would like to mention, is the contracted pelvis. Pelvic contraction is a condition more common than generally supposed, and usually not recognized until the patient is in labor, or has been in labor some time, and because of this tardy recognition of this condition I feel we are not doing our duty to our patients, who have engaged us months previous to the labor and expect us to do our best for them. This condition has caused me more worry than any other obstetrical complication, and I wish to give you the treatment that I have found gives the best results.

The average practitioner is careful to examine the urine at regular intervals, looks after the general health, etc., but does not make a preliminary examination before labor, noting the position and presentation of the child and the presence or absence of pelvic contraction.

When a woman comes to engage me to look after her pregnancy and labor I enquire whether she is, a primipara or multi

para.

If she is a primipara I want to examine her thoroughly three weeks before the expected date of labor, noting the position and presentation of the child and whether or not the head is fixed in the brim of the pelvis at this time.

If she is a multipara I enquire regarding her previous labors, because if she has had more than one child her labors will be much the same, in so far as the passage of the head into the pelvis is concerned.

First then, supposing that she is primipara and I call on her three weeks before the expected date of labor, I first make an abdominal examination noting the position and presentation of the child. If it is a breech or transverse usually a little external manipulation will change the presentation to a veriex, and it is much easier to do this external version now than at full term. If the position and presentation is normal and the head well fixed in the brim of the pelvis, I do not take the pelvic measurements, because I know that everything will be all right, as it is usually the brim of the pelvis that causes the