7. DILATING THE CERVIX - Now the cervix is fixed in a single toothed tenaculum forceps by placing one tooth in the ostium and the other tooth on the upper lip. A goodly mass of tissue should be taken in the forceps to prevent it tearing out during dilation.

Dilation of the cervix is described in some detail since it is the most difficult part of the procedure with the greatest incidence of complications. Conditions of the cervix which complicate dilation are described in Chapter 11. . Perforations occur mostly during dilation, see Chapter 12 .

In practically all cases the cervix must be dilated to admit the aspiration canula and other instruments. Many doctors prefer to sound the canal to get an impression of its direction. Others condemn this with the argument that it does not give any information which can not be obtained by introducing a dilator and that it has a risk of perforation. Our experience is that in cases where dilation is difficult or where the dilator meets a sudden resistance the uterine probe can clarify this problem. It needs much less force to enter the cervical canal with a probe than with a dilator so that it can check the resistance by gentle handling. The dilator needs rather much force even it is rightly in the cervical canal so that the difference between a normal canal and a mechanical resistance can not easily be distinguished. In certain difficult cases, like duplicate uterus, sounding is necessary because of the unpredictable course of the canal.

Dilation is done by forcing dilators through the canal. Another method forms the use of prostaglandins e.g. 400 mg of misoprostol given buccal two hours before treatment.

As a guide maximum dilation should be so many millimetres as weeks pregnancy, with a minimum of six and a maximum of twelve mm. Generally dilation is easier in a more advanced pregnancy, but this is by no means always so. Too little dilation leads to difficulty in removing the tissues. Either the canula can not remove the placenta from its implantation site or the products repeatedly get stuck in the cervical canal or in the canula, in which case they must be carefully removed with a sterile slender forceps. Too much forceful dilation eventually may cause cervical incompetence leading to spontaneous abortion in later pregnancies.

To prevent damage to the cervix dilation should be done gradually, so that little force is necessary. Application of too much force causes the cervix to tear out of the tenaculum. This is especially the case in the long slender cervix. Gradual dilation is done by using numerous Hegar dilators, but much simpler is the use of tapering dilators. Pratt dilators (ranging from 4.5 till 14 mm), and Hank dilators (4.5 till 10 mm) have the disadvantage that they are double ended. Jolly dilators range from 3/7 to 18/24 mm, they are available as a complete set or as a limited set (3/7 to 12/18 mm). The Hawkin Ambler dilators, ranging from 3/6 till 18/21 mm, are highly recommended. Each dilator is identified by two figures which indicate the minimum and maximum dilation in mm. The recommended set is five dilators sizes 3/6 till 7/10 for pregnancies up till 12 weeks, and four dilators 8/11 till 11/14 for more advanced pregnancies. Their advantage over the Jolly dilators is that they admit more gradual dilation. They cover the range 3 till 14 mm in nine dilators, the Jolly's cover 3 till 15 mm in only four dilators.

Occasionally it is very difficult to find the external ostium and the cervical canal, especially after some form of cervical surgery. It may be necessary to dilate with very tiny dilators, for which purpose a set of Hegars 2 till 5 should be available. Very gradual dilation can be obtained with laminaria or Dilapam ® but this takes a few hours. In practise the use is limited to those cases where dilation is impossible without using excessive force risking cervical damage. Application of prostaglandin tablets like misoprostol in the vagina may lead to softening of a rigid cervix so that dilation is easier. The use of these methods to obtain a termination of pregnancy is described in Chapter I and Chapter 6. Their use to aid dilation is described in Chapter 11.

Sometimes it is difficult to find the internal ostium of the cervix. The point of the dilator gets lost in the weak wall of the canal. If this is not understood the doctor may think that he reached the fundus of a small uterus and then he does a cervical curettage leaving the pregnancy undisturbed. If in this condition force is applied the dilator will cause a perforation of the cervix wall which may eventually disrupt the uterine vessels.

8. ASPIRATION OF SOFT TISSUE - Now the canula is brought into the uterus. It may be already connected to the pump but during introduction no vacuum should be applied. It is very convenient if the connection with the pump has an opening to admit air from outside to cancel the vacuum. The simplest way to achieve this is an opening in the connecting tube which can be closed with a thumb. In the young pregnancy the canula can be gently pressed against the fundus as a check that it is actually inside the uterus and not through a perforation in the abdomen. In the advanced pregnancy the uterus is generally too deep to reach the fundus with the canula. If there is no evidence of a perforation the vacuum is applied by switching on the pump or by closing the opening. The canula is gently moved up and down and at the same time rotated. Contrary to classical curettage, where the curette is pressed against the uterine wall, in suction curettage the wall is sucked against the opening in the canula.

In the young pregnancy the uterus is completely evacuated. In the advanced pregnancy first the amniotic fluid is sucked away. This causes the uterus to shrink which diminishes blood loss considerably. The placenta is removed.

In second trimester procedure the doctor should try to do this at the end of the procedure to prevent amniotic fluid or fetal tissue to enter the maternal circulation in the relatively great wound at the uterine wall left after removal of the placenta. Occasionally a condition like accrete placenta is encountered (Chapter 11.). The complications which can arise from this situation are discussed in Chapter 12. . During aspiration placental tissue may block the canula. The moving of the canula in the uterus has then no resistance as if you arc moving in butter. In that case the vacuum must be discontinued and the canula taken out. Mostly the tissue will remain in the cervical canal because it is still fixed to the uterine wall. It can be grabbed with a slender forceps and carefully torn loose with jerky movements. If the canula is blocked by tissue that can not be aspirated it should be pulled out of the canula with a forceps. Do not employ the disgusting habit of beating the canula on the sterile field to shake the tissue out. You make a mess of the table and spray blood droplets which may contain aids virus over yourself and your assistant.

If the uterus is empty this can be felt by the rasping sensation of the canula. This is much more marked when using a rigid canula than a soft Karman type. Bleeding after total evacuation is rare. If bleeding occurs there is most likely retention of a peace of placenta or fetal parts, there is a laceration of the uterine wall or a perforation. The only cause of abundant bleeding in an empty uterus, which can be fatal, occurs in the case of cervical implantation of the placenta. This very rare event is discussed in Chapter 12. .

Shortly after evacuation of the uterus the patient may feel more or less painful contractions of the uterus. They diminish in about ten minutes. Occasionally the pains return in a very severe form after some time. This may even look alarming. Mostly the cause is trivial. The cervix has closed itself or it is blocked by a blood clot. Slight internal bleeding from an small artery fills and distends the uterus which is very painful. The therapy is very simple. The patient is brought back to the theatre where a narrow canula is brought into the uterus. Most blood streams out giving instant relieve. It is wise to aspirate the uterus again with a narrow canula to remove possible small pieces of retained placenta.

9. USING THE FORCEPS - A pregnancy till about 13 weeks can be terminated by aspiration only. In more advanced pregnancies, generally over 13 till 14 weeks, it is generally not possible to remove the fetal parts with the canula alone. Occasionally large parts are stuck in the canula and removed, but often certain parts, notably the caput and the vertebral column can not be removed. After aspiration the uterus is contracted, especially if ergometrine is used as premedication. This prevents or at least diminishes blood loss, but it tends to trap the foetal parts. The forceps should always be brought closed into the uterus and opened when it is inside. This is to prevent damaging the wall of the cervix. The forceps should not be brought till the fundus to search for foetal parts to prevent perforation. For non experienced doctors it is not always clear if the forceps holds a foetal part of a part of the uterine wall. Instead the canula must be brought into the uterus so that the foetal parts can be mobilised by suction. For less experienced doctors it is good practice to touch the fundus gently to check that the forceps is inside the uterus and that it did not enter the abdominal cavity through a perforation.

In difficult cases the procedure can be done under continuous monitoring with ultrasound scan. While the doctor searches for foetal parts an assistant keeps the transducer on the abdomen so that the movements of the forceps can be seen on the screen. Always bring parts in line with the cervical canal before extraction.

Difficulties with aspiration and D&E are discussed in Chapter 11. Complications which may arise in Chapter 12.

10. BLUNT CURETTAGE - Most doctors feel better if they check the fact that the uterus is empty by trying it with a blunt curette. If it is done carefully there is little chance of perforation. A better way to find out if all parts are removed is by means of ultrasound and by checking the removed tissues. A real sharp curettage after the aspiration has no advantages and should not be done. Every lesion of the uterine wall may lead to adhesions (Asherman's syndrome), infertility and dysmenorrhoea. Lesions of the uterine wall may be the site of placenta accreta or increta in further pregnancies.

11. CHECK OF TISSUES - After the procedure the removed tissues must be checked to make sure that the pregnancy is completely terminated and to find out if the pregnancy was normal. This is particularly necessary in the young pregnancy. In the advanced pregnancy the emptiness of the uterus can be more adequately checked by means of ultrasound scan. The easiest way to check the tissues is as follows. After the procedure the contents of the bottle which receives the products is shed in a large household sieve and washed under a running tap to remove blood. The contents of the sieve is then shed into a flat glass tray, for instance a refrigerator tray and examined with a light source under it. Ideally the table near the zinc has a window of white glass with a lamp under it for this purpose. The following tissues can be distinguished:

1. decidua

2. placental tissue

3. chorion membranes

4. amnion membranes

5. umbilical cord (after about 9 weeks, not always found)

6. foetal parts (after about 9 weeks)

If nearly nothing is found, or only some bloody scraps, the woman was not pregnant or the pregnancy is not reached. Most likely is that only the cervix is curetted, mistaken for a very small uterus. Ultrasound will give the solution. Lacking a scanner, a proper repeated examination combined with test should give the solution. For this reason it is recommended to keep a urine sample of every patient till the termination is finished and the results are checked. If a test is required this can then be done without waiting till the patient can pass urine.

If only decidua is found, a white homogenous mass without structures, the diagnosis ectopic pregnancy is practically certain, or the non pregnant half of a duplicate uterus is emptied. Ultrasound scan will give the right diagnosis, which of course should have been found before starting the procedure.

If little vesicles are seen in the placental tissue this is a sign of molar pregnancy. Since this may develop into a chorion epithelioma it is necessary to do a thorough sharp curettage, and to instruct the patient to come back after three weeks. Than a pregnancy test should be done. If positive a fractional test may be done to estimate the hCG level. Generally the clinic will refer the patient to a hospital for further investigation.

If membranes are found the diagnosis intrauterine pregnancy is certain. If there is only very little tissue with fragments of membranes it is either a very young pregnancy or the termination is not complete: part of the placenta is still inside the uterus. This is often the case if the procedure is done with inadequate dilation and a narrow canula. If the patient is allowed to go home in the best case she will have a lengthy period of blood loss before eventually shedding the remaining tissues. Infection is a real danger. Often she must be hospitalised for a D&C. Therefore in the case of too little tissue the procedure must be continued with a new set of instruments, carefully dilating a bit further and checking for tissues in the uterus. Occasionally a sharp curettage will be necessary.

To prevent the difficulties related to the very young pregnancy patients should be appointed so that their pregnancy is as close as possible to 8 weeks. This is the pregnancy age in which the procedure is easiest with least complications. In the very young pregnancy there is a risk of retention of placental tissue or the pregnancy may develop undisturbed. See Chapter 13.

12. CHECKING WITH ULTRASOUND SCAN - Particularly in the advanced pregnancy the check with a scanner is useful to detect retained products. It is not always easy to be sure that the uterus is empty. A check with a curette may be misleading because the foetal parts which are close to the uterine wall may not be detected. However, if the uterus is empty the scan may give false information because the internal lining of the uterus is disturbed. Perforations have been caused by fervently trying to remove suspected retained tissues which in reality are artifacts.

As discussed before, if in the young pregnancy little or no tissue or only decidua is removed, a scan should be made to find the proper diagnosis.

13. FINISHING THE PROCEDURE - The last act with the canula should be the removal of blood and tissue rests from the vagina. The tenaculum and speculum are removed. The patient is cleaned and a sterile hygienic pad is applied. To keep this in place the patient is provided with a disposable slip.

She is then helped from the table and into a bed. In most cases she is well able to walk. In general anaesthesia or heavy sedation that may be difficult or even impossible, so that she has to be replaced with a trolley. Because some blood loss may occur she should be placed on a impermeable tissue to keep the bed clean. Occasionally a patient vomits, so a kidney dish or similar should be available at her bedside. After some fifteen minutes a check for blood loss should be done. By that time the patient will be able to drink something. Try tea first and if that does not lead to vomiting something else can be given. If blood loss is more than occurs in a normal period the pad should be changed and waited another half hour. If bleeding continues an ultrasound scan should be done to check retention.

Occasionally the patient has no blood loss but increasing abdominal pain. In that case the uterus is filled with blood which is trapped, causing extension of the uterus. The cure, repeated aspiration, is already mentioned.

If blood loss continues at a steady pace no risks must be taken. Never wait more than an hour, or shorter in heavy blood loss, to send her to a hospital. If bleeding does not stop within an hour it will not stop at all.

If the patient has a Rhesus negative blood group the administration of Rh anti-D- immunoglobuline may now be considered (Chapter 14 ).

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