HEART DISEASE

GENERAL MEASURES. Try to ensure that a mother has as much rest as possible and avoids undue weight gain, fluid retention, infection, and anaemia. Keep her haemoglobin above 100 g/l. If necessary, transfuse her with packed red cells, and give her furosemide.

GROUPS ONE AND TWO. Allow her to go through pregnancy; see her regularly in the antenatal clinic: she is unlikely to go into failure.

GROUPS THREE AND FOUR. If possible, try to prevent her from becoming pregnant.

If pregnancy has not progressed beyond 12 weeks, opinions vary. (1) If she is well cared for, death from heart failure in pregnancy or labour is rare, so avoid termination. Some obstetricians working under ideal conditions never terminate a pregnancy for heart disease. (2) If care is less good, a therapeutic abortion might be indicated.

If she goes into failure during pregnancy, admit her for bed-rest and control it. Give her frusemide (furosemide). If possible restrict the sodium in her diet. Digoxin is indicated if she has auricular fibrillation, otherwise its value is disputed. If failure is controlled, she can go home, provided you can keep in touch with her, and she and her family realize that she must rest.

Figure 17.5: A CARDIAC PATIENT IN LABOUR. A, during the first stage deliver her sitting up. B, during the second stage avoid the lithotomy position. Sit her up with her buttocks over the end of the bed. Ask two assistants (not shown) to support her with her legs resting on chairs. Discourage her from bearing down as much as you can.

DELIVERING A MOTHER IN HEART FAILURE

Admit a mother with heart disease at 34 weeks, or earlier, if she goes into failure before then. For all degrees of heart disease vaginal delivery is likely to be safer than Caesarean section. Avoid section late in labour. If you expect complications, do it electively under general anaesthesia. Beware of cardiac failure developing after delivery as oedema fluid returns to her circulation.

If she has valvular disease, prevent endocarditis. Give her 3 doses at 8-hour intervals of: (1) ampicillin 500 mg orally or intramuscularly; and (2) gentamicin 80 mg intramuscularly. Or give her any other broad-spectrum antibiotic which is safe in pregnancy. Give the first dose when her membranes rupture, or you will encourage the growth of resistant organisms.

EQUIPMENT. Prepare for a cardiac emergency, and have digoxin, frusemide, aminophylline, and morphine ready. Also, a venesection set (M 13.4), tracheal tubes, a laryngoscope, and oxygen.

FIRST STAGE. Deliver her sitting up. Adequate analgesia is essential. Epidural anaesthesia is ideal, if you are skilled, because it decreases cardiac output. If this is impractical, give her morphine rather than pethidine.

Count her pulse and respiration rate every 30 minutes. If her pulse rises above 100 and her respirations above 24, and she is obviously dyspnoeic, she is in failure.

SECOND STAGE. Avoid the lithotomy position. Sit her up with her buttocks over the end of the bed. Ask two assistants to support her with her legs resting on chairs. Discourage her from bearing down as much as you can.

If she progresses quickly, allow her to deliver spontaneously. If her progress is slow, shorten this stage with outlet forceps or a vacuum extractor, or a generous episiotomy. Use enough local anaesthetic to prevent her feeling pain, and sit her up when you suture it.

Give her frusemide 40 mg intravenously, as soon as she is delivered.

THIRD STAGE. A small bleed is likely to benefit cardiac failure. So only give her ergometrine with oxytocin (’Syntometrine’), if she has lost more than 500 ml. If you give it when she has not bled, the sudden return of blood to her circulation from her contracting uterus may precipitate failure.

Watch her carefully for the next 24 hours, because this is the time when she is most likely to go into failure.

CAUTION! (1) Don’t overload her circulation, and avoid transfusion, especially after delivery. (2) Don’t use local anaesthetics with adrenalin in them.

If you have used morphine, have nalorphine or naloxone ready for the baby. After delivery watch her pulse, temperature, and respiration carefully, and watch for puerperal infection. Advise her not to become pregnant again, and give her family-planning advice—preferably tie her tubes.

DIFFICULTIES DELIVERING A PATIENT WITH CARDIAC DISEASE

If she goes into CARDIAC FAILURE which was not previously diagnosed or treated, give her intravenous morphine 10 to 15 mg, intravenous frusemide 40 to 80 mg, and if necessary apply rotating tourniquets (M 13.4). Give her oxygen through a nasal tube, and aminophylline 250 mg during 10 minutes timed by the clock. If she is fibrillating give her intravenous digoxin.

If her cervix is partly dilated and she is NOT IN SEVERE FAILURE, allow delivery to proceed vaginally. Interference of any kind is likely to make her worse.

If she is in SEVERE FAILURE AFTER FULL DILATATION, and you don’t expect delivery in the next few minutes, deliver her with the vacuum extractor, or outlet forceps.