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Management of labor/ delivery with pre existing hypertension 4 страница
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Cesarean section is followed by radiation therapy.
4. If cancer is inoperable and if the presenting part is through the cervix:
Labor is followed by radiation therapy (as soon as involution permits).
Local Diseases with Pregnancy
Deformities of the Parturient Canal
Embryologically, the uterus and vagina are formed by the fusion of the two mullerian ducts, the union taking place from below upward. Lack of fusion at any point or throughout the length of the two canals explains almost all of the anomalies that are observed, and rudimentary development of one duct will account for the rest. It is not rare to find the uterine fundus indented in the middle — the " uterus arcuatus" — which is the upper end of the line effusion of the two ducts. The two sides of the uterus and vagina are not always equally developed and gradations from complete development of the two halves to almost entire absence of one mullerian duct are observed. The rudimentary side lies as an appendage to the well-developed uterus but since its canal, four times out of five, does not communicate with the vagina complications sometimes ensue, such as hematosalpinx, hematometra and pregnancy in the closed horn. Malformations of the urinary tract often accompany genital deformities.
Duplex Uterus and Vagina
Coitus is rarely interfered with as the larger vagina is used. Menstruation issues from both uteri simultaneously, but sometimes only from one at a time. Pregnancy may occur in one or both horns. If each horn contains an ovum the two children may theoretically have been conceived at different impregnations and be delivered at intervals, thus suggesting superfetation. When pregnancy occurs in one horn it is ordinarily undisturbed; the side not involved grows and forms a decidua similar to that in ectopic gestation. The decidua of the empty side may be cast out while the pregnancy continues on the other side. The course of the case resembles an abortion and unless the existence of a double uterus is known the physician will curet and unwittingly destroy a living ovum. Usually the decidua sloughs away in the puerperium with the lochia. Abortion occurs more frequently than usual. It may be difficult to clean out the uterus, especially if there is only one cervix. It is doubly important to insert the finger for the curettage. Labor is often normal but the following complications have been observed: weak pains, atony with postpartum hemorrhage in the third stage and adherent placenta. The nonpregnant portion of the uterus may prolapse under the other and act like a tumor incarcerated in the pelvis. The nonpregnant cervix may be forced down to the vulva with the head. The uterus may rupture because of poor musculature and the septum in the vagina may act as an obstruction. Septate uteri may have the following complications: breech and transverse presentation, weak pains, postpartum atony, rigidity of the cervix, an adherent placenta on the septum and, if the septum is in the cervix, obstruction to delivery. In two of our cases the child straddled the septum in the cervix.
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Management of Pregnancy and Labor in Cases of Double Uterus
Women with double uteri have a high degree of fertility but the incidence of spontaneous abortion is also high. If women have repeated abortions but no living baby it is advisable to operate in the hope of making a single uterine cavity. This may be accomplished by removing an accessory horn or the septum.
During pregnancy, because of frequency of abortions, the patient's activities must be restricted especially around the time the menses would have appeared. Perhaps progesterone (10 mg) administered hypodermically every day at this time will help. Bed rest may be necessary.
During labor the patient must be watched very closely. Malpresentations, such as breech and transverse, are common and may be the deciding factor for the performance of a cesarean section. Likewise the possibility of a weakened uterine musculature must be remembered; therefore all patients with a double uterus should be delivered in a hospital. In most cases delivery can be accomplished safely from below either spontaneously or with aid. At the time of labor a cervical or vaginal septum should be removed. This may usually be done when the presenting part pushes the septum almost into view or it may be done after the baby is delivered. Certainly if the septum is a hindrance to the exit of the baby it should be incised or excised. The third stage is usually normal but one must be prepared for hemorrhage from the weak musculature and from the retained placenta.
Rudimentary Uterine Horn
Pregnancy in a rudimentary horn resembles ectopic gestation very closely. There are many complications in this group of patients and a few near deaths. An extremely rudimentary accessory horn may be closed at both ends, making pregnancy impossible, but an accumulation of menstrual blood is probable. Should the fertilized ovum be inserted in the small horn there is no hope of its finding a way into the uterine cavity of the other, because the connecting bridge of tissue is usually imperforate. Even if the two halves are broadly apposed the two cavities usually do not communicate. Hypertrophy of the muscular wall of the horn may occur and permit the ovum to grow to term, but more commonly rupture of the gestational sac occurs during the middle of pregnancy and profuse internal hemorrhage ensues. Since there is no communication with the vagina the spermatozoa must cross over from the open tube to the closed side, to fertilize the ovum from the ovary on the side of the pregnancy, or the ovum from the open side wanders over to the closed horn before or after fertilization.
The diagnosis of pregnancy in a rudimentary horn is occasionally made but usually the abdomen is opened for rupture of a supposed extrauterine pregnancy. On the specimen it is easy to find the connecting band between the rudimentary and the spindle-shaped larger horn and to determine that the round ligament and the tube come off from the outside of the gestational sac. Septate vagina or cervix may be indicative of the presence of some other anomaly and palpation of the pedicle or connecting cord will confirm the diagnosis. If the fetus dies identical changes in the ovum may follow, as in ectopic ova and later, owing to adhesions and shrinkage of the sac, the preoperative diagnosis is usually a fibroma or an ovarian cyst. Contractions occurring in the sac of the tumor may suggest the clue to a correct diagnosis.
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Treatment is the same as that of extrauterine pregnancy, and even more active intervention is indicated as soon as the diagnosis is made. At laparotomy it is best to remove the whole sac if possible.
Diverticula of the Uterus
These are rare. In one of our cases the placenta was developed in an accessory uterine cavity connected with the main portion by a passage. It is probable that these are cases of septate uterus with an incomplete septum. Incarceration of the placenta in a horn of the uterus is not rare.
Local Inflammations
Vulvitis
Owing to edema and congestion of the vulva and to the pronounced projection of the pelvic floor which exposes the organ to injury, vulvitis is not rare in gestation. Lack of cleanliness, obesity, difficulty in keeping the vulva clear of mucus and smegma and purulent discharges, together with the exposure of the introitus, invite infection and eczema. Mycotic infections, resembling thrush of the mouth, which may cover the whole of the hyperemic and moist vulva, and purulent infections, including gonorrhea, occur. Vegetations or condylomas may be seen on the labia minora or in the raphe and occasionally they may attain enormous size. The pudendal region is the habitat of Escherichia coli, staphylococcus and streptococcus, with hosts of others.
Bartholinitis
This is often but not always due to the gonococcus. Because of danger of puerperal infection an abscess should be cured before labor, preferably by the electric cautery. Cysts of the labia, if not infected, are best left alone until after the puerperium. If they obstruct delivery, puncture and aspiration of their contents will remove the obstacle, or the cysts may be opened and their lining destroyed by means of electric cautery.
Vaginitis
It is not rare to find a reddened granular, thickened mucosa in the fornices, vaginitis granulosa, but occasionally colpitis emphysematosa is present. In this condition the vaginal wall is full of large and small cysts and the epithelium is congested. This abnormality disappears spontaneously after delivery. All discharges must be studied by fresh hanging drops and stained smears to detect the causative organism which may be Trichomonas vaginalis, monilia or gonococcus. The trichomonas is readily observed in a hanging drop because of its motility. The treatment we recommend is washing the vagina with tincture of green soap, drying and instilling an acid-glucose powder. In cases of trichomonas and gonorrhea, after the organisms have disappeared, vaginal douches containing approximately 60 g of white vinegar to a full douche bag 1. 4-1. 5 l or lactic acid douches are helpful.
Gonorrhea
Acute gonorrhea is more common in primiparas, being conveyed at the time of impregnation. Unlike ordinary cases of acute gonorrhea, in which the inflammation is limited to or most pronounced in the urethra, the vulvar glands and the cervix, in the pregnant patient the gonococcus, favored by the succulency of the tissues, attacks the vaginal and vulvar epithelium in addition to the areas just mentioned. Profuse secretion of greenish-yellow pus results; the vulva is red and sometimes covered with grayish exudate, sometimes ulcerated or covered with pointed condylomas; the vagina is thick and granular, like a nutmeg grater, and bleeds even on light touch; the cervix is swollen, vascular, eroded, easily vulnerable and emits a foul mucopus in which the gonococci are readily found. Chronic infection is the form usually encountered and it has left the surfaces, covered by squamous epithelium, to localize in the urethra, Skene's tubules, the crypts around the hymen, the bartholin ducts and glands and the cervix, in which it is recognizable by the usual signs. Acute as well as chronic gonorrhea may affect the uterine decidua and cause abortion but as a rule the gonorrheal infection remains latent until after delivery. Many women having a slight mucopurulent leukorrhea are delivered without the physician being aware of the existence of infection until the baby's eyes show gonorrheal ophthalmia. Through the traumatism of labor the gonococci are pressed out of the deep cervical glands and by virtue of the open cervix and the puerperal processes unlimited opportunities are afforded to them for further virulent development. As a result gonorrheal endometritis, salpingitis, ovaritis and pelvic peritonitis ensue. Acute infections are likely to show the exacerbation in the first days of the puerperium, because of the associated streptococci and staphylococci. Chronic gonorrhea causes the " late fevers" of the tenth to the thirteenth day; that is, an ascending inflammation which results in pus tubes or adhesive obliterating peritonitis, often leaving permanent sterility and gynecologic invalidism. Acute gonorrhea in gestation can cause rheumatism with disorganization of the joints (wrist, knee and hip) or even endocarditis and general septicemia.
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Diagnosis. Repeated bacteriologic examination of secretions is often required for the detection of gonococcus. In the acute cases smears are dependable but in chronic cases smears alone are of little value. The diagnosis must usually be made following cultures and fixation tests. However, a combination of smears and cultures may be used to great advantage. One negative smear and culture do not rule out gonorrhea. The history is valuable. An obstinately inflamed single joint is strongly suggestive. Ophthalmia in the infant does not prove the existence of gonorrhea in the mother unless the gonococcus is found in the pus and other sources of infection of the child's eyes are eliminated.
Treatment. Gonorrheal infections appear more persistent and resistant to treatment during pregnancy. In acute cases rest in bed is important. The diet should be bland and alcohol and spices avoided. Sexual intercourse must be forbidden. At present cures are readily obtained by administering sulfonamide derivatives and penicillin. Some authors recommend local therapy to the vulva, vagina and cervix in addition to the antibiotics by mouth. For example, applying an ointment containing 2 per cent of allantoin, 15 per cent of sulfanilamide and 5 per cent of lactose in a special greaseless base buffered to a pH of 4. 5 with lactic acid. Sodium penicillin produces dramatic results in gonorrheal infections. Smears and cultures should be taken at intervals of twenty-eight days to be certain that a cure persists. If gonococci return the treatment must be repeated. Should abortion occur curettage is not to be undertaken if it is at all avoidable.
During labor in cases of known gonorrhea a 1: 1000 solution of metaphen should be instilled into the vagina every six hours. Vaginal explorations and operations are limited to an irreducible minimum, the bag of waters is saved, if possible, until the child's head is fully delivered and every precaution is taken to prevent the entrance of vaginal mucus into the conjunctival sacs. Immediately after the baby is born silver nitrate or silver acetate must be instilled into its eyes. This should be repeated on the second and third days. During the puerperium the patient should be kept in bed fully ten days to prevent the ascension of the infection through the uterus to the tubes.
Erosions and Hypertrophy of the Cervix
Erosions and hypertrpohy of the cervix are frequent and since the softened vascular structure bleeds readily the flow may suggest abortion. Erosions need not be treated during pregnancy unless they bleed. If they are friable the electric cautery may be applied safely to correct the condition, but care must be exercised not to place the cautery needle too near the internal os nor too deeply into the cervical tissue. Often applications of silver nitrate will suffice.
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Self Test
1. A pregnant woman with anemia of the 2nd degree is at high risk of
A. hemorrhages during labor.
B. postmaturity.
C. prematurity.
D. big fetus.
2. Which of the following is a sign of heart disease in pregnancy?
A. edema of lower extremities
B. systolic murmur
C. increased respiratory effort
D. arrhythmia
3. The diagnosis of diabetes in pregnant can be presumptive if
A. the fasting blood sugar exceeds 180 mg.
B. a 2-hour value exceeds 140 mg% in glucose tolerance test.
4. The infant of a diabetic mother is not at risk of
A. increased perinatal death rate.
B. hypocalcemia.
C. hyperglycemia.
D. neural tube defects.
E. macrosomia.
5. Which of the following does not contribute to the development of acute urinary tract infection during pregnancy, delivery, and in the puerperium?
A. compression of the ureter by a large uterus at the pelvic brim
B. increased tone and peristalsis of ureters
C. symptomatic bacteriuria
D. bladder catheterization following delivery
6. An optimum term of delivery for the patient with diabetes is:
A. 36-37 weeks of gestation
B. 34-35 weeks of gestation
C. 37-38 weeks of gestation
7. Pregnancy and delivery are not contraindicated for patients with:
A. active rheumatic carditis, recurrent rheumatic carditis, bacterial rheumatic carditis
B. circulatory insufficiency
C. mitral stenosis of 1 stage (according to A. Bakulev’s classification)
D. combined valvular disease with stenosis prevalence
E. tricuspid incompetence
8. Every patient with cardiovascular disease should be hospitalized thrice during pregnancy:
A. at term of 12, 26-32 and 36-37 weeks of gestation
B. at term of 16, 20-22, 39-40 weeks of geatstions
9. Pregnancy is contraindicated for patients with:
A. pyelonephritis complicated by azotemia or hypertension
B. chronic pyelonephritis
C. acute pyelonephritis at term of 28 weeks of gestation
10. What can be performed at pregnancy complicated by cancer if the latter is operable and the child is viable?
A. radium therapy is followed by delivery by abdominal hysterotomy
B. cesarean section is followed by Wertheim's operation
C. radical excision (Wertheim) of the uterus
D. radium therapy is preceded or followed by cesarean section
Chapter 27. Isoimmunization in pregnancy
Definition.
Isoimmunization, or maternal blood group immunization, is the development of circulating antibodies by the mother directed against an antigen of fetal origin. Isoimmunization is also referred to as maternal sensitization. The presence of maternal red blood cell antibodies during pregnancy is a rather common problem in clinical practice and is accompanied by the development of obstetric complications that lead to increased rate of maternal morbidity and perinatal morbidity and mortality. Isoimmunization in pregnancy most often involves the Rh system of red-blood-cell antigens, but it can also involve ABO antigens, and other blood group incompatibilities.
Types of isoimmunisation:
· Rhesus (C, D, E)
· ABO
· Kell
· Duffey
· c (know as 'little c')
· Platelets
Rh-factor is present in blood of 85% of population (Rh-positive blood), in about 15% of population this factor is absent (Rh-negative blood). There are more than 288 types of Rh-factor, but the most famous and important are C, D, E.
The antibodies, which are directed against fetal red cell antigens, can cross the placenta and cause fetal hemolytic disease.
Etiology and Pathogenesis
Rh-incompatibility develops when an Rh-negative woman is pregnant with Rh-positive fetus. It is unknown, why the sensibility to Rh-positive antigen is different in different patients, but only 15-25 % of Rh-negative pregnant women with Rh-positive fetus have incompatibility during pregnancies.
Rh-isoimmunization develops since 8-9 weeks of pregnancy, when the differentiation of Rh-factor begins. As a rule, the first (and even second pregnancy) does not lead to Rh-incompatibility. Throughout the pregnancy, small amounts of fetal blood can enter the maternal circulation (feto-maternal hemorrhage), with the greatest transfer occurring at the time of delivery or during the third trimester. This transfer stimulates maternal antibody production against the Rh factor, which is called isoimmunization. The process of sensitization has no adverse health effects for the mother. During the time of first Rh- positive pregnancy, the production of maternal anti-Rh antibodies is relatively slow and usually does not affect that pregnancy. Rh- incompatibility is not a factor in a first pregnancy, because few fetal blood cells reach the mother’s bloodstream until delivery. But every subsequent pregnancy is followed by increased development of incompatibility by Rh-factor because fetal RBCs move across the placenta to the maternal circulation. The main reasons of introduction of fetus antigens to the maternal blood vessels are the following:
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· Rupture of the vessels of the placenta (placental abruption, placenta previa, spontaneous abortion, threatened abortion).
· Capillary hyperpermeability (preeclampsia and eclampsia syndrome, diabetes, obesity).
· Manual removing of the afterbirth.
· Cesarean section.
· Therapeutic abortion.
· Chorionic villus sampling
· Amniocentesis
· External cephalic version
· Other causes of maternal anti-Rh antibody production include injection with needles contaminated with Rh-positive blood and inadvertent transfusion of Rh-positive blood.
Movement is greatest at delivery or termination of pregnancy. Movement of large volumes (eg, 10 to 150 mL) is considered significant fetomaternal hemorrhage; fetal RBCs stimulate maternal antibody production against the Rh antigens. The larger the fetomaternal hemorrhage, the more antibodies produced. Rh-isoimmunization is caused by maternal antibody production in response to exposure to fetal RBCs antigens of the Rh-positive group, including Cc, Dd, Ee. When the antigen is introduced into the circulation of a rhesus negative mother, it stimulates the production of an antibody in the form of agglutinin. No complications develop during the initial sensitizing pregnancy. The antibodies that form after delivery cannot affect the first child. However, if the mother is exposed to the Rh- D antigens during subsequent pregnancies, the immune response is quicker and much greater. The anti-D antibodies produced by the mother can cross the placenta and bind to Rh- D antigen on the surface of fetal red blood cells, causing lysis of the fetal RBCs, resulting in development of hemolytic anemia of the fetus. Hemolysis of RBCs causes anemia, hypoalbuminemia, and possibly high-output heart failure or fetal death.
There are 3 types of antibodies: complete, incomplete agglutinative, incomplete blocking. Complete antibodies can agglutinate red cells in saline medium; they have a large molecule, and do not pass through the placenta. Complete antibodies are immunoglobulins of M class (IgM). Incomplete agglutinative and incomplete blocking antibodies are immunoglobulins of G and A classes (IgA and IgG), they agglutinate red cells in colloid medium (blood, albumin, plasma). They have a small molecule, easily penetrating through the placenta to the maternal blood circulation and having the primary significance for patients.
The primary response causes a production of IgM that does not cross the placenta. The fetus is therefore not affected by this process. But, if the mother is subsequently exposed to the same red blood antigen, the production of IgA and IgG antibodies quickly occurs. Maternal IgA and IgG antibodies are actively transported across the placenta, and bind to the fetal red cell antigen causing erythrocyte destruction and hemolysis.
Anemia stimulates fetal bone marrow, spleen and liver to produce and release immature RBCs (erythroblasts) into fetal peripheral circulation (erythroblastosis fetalis develops). Hemolysis results in elevated indirect bilirubin levels in neonates. Non-bound (indirect, free) bilirubin, which is released due to hemolysis is very toxic for the fetus. Indirect bilirubin is not water-soluble; it cannot be removed from the organism by kidneys.
In the liver of the fetus free bilirubin is bound with 2 molecules of glucuron-acid, and this form is named bound (direct, combined) bilirubin which is water-soluble, and the kidneys are responsible for its removing from the organism. In this way fetal hemolytic icterus develops.
Disturbances of the function of the fetus liver may lead to the development of a severe form of hemolytic disease, such as nuclear icterus (kernicterus). When levels of total serum bilirubin exceed 25 mg/dL, unconjugated bilirubin can enter brain tissue and cause apoptosis and necrosis. This leads to acute bilirubin encephalopathy that may result in permanent neurologic damage (kernicterus).
On the other hand, the disturbances of the liver lead to hypoproteinemia, causing the increase of capillary permeability and development of edema of the fetus. There are 3 types of hemolytic disease of the fetus: hemolytic anemia, hemolytic anemia with icterus, hemolytic anemia with icterus and edema.
Rh-isoimmunization can also develop after transfusion of Rh-positive blood to Rh-negative patient, and in this case isoimmunization will be of great significance even in primipara.
Antepartum hemorrhage, hypertensive disorders in pregnancy, prophylactic external version of the fetus, invasive diagnostic procedures( eg., amniocentesis are all associated with larger volumes of blood than in transplacental hemorrhage, which leads to the progress of Rh sensitization and increasing of risks for the fetus.
Thus, mains steps of pathogenesis are:
1. Maternal sensitization against a fetal blood-group antigen
2. Maternal production of IgG antibodies
3. Transplacental antibody passage to the fetus
4. Antibody-mediated hemolysis in the fetal circulation, resulting in fetal anemia. (Fig. 176)
Fig. 176 Development of Rh-isoimmunization.
Clinical presentation of a hemolytic disease in a new born varies from mild jaundice and anemia to hydrops fetalis (with ascites, pleural and pericardial effusions). Because the placenta clears bilirubin, the chief risk to the fetus is anemia. Extramedullary hematopoiesis (due to anemia) results in hepatosplenomegaly.
Risks during labor and delivery include asphyxia and splenic rupture. Postnatal problems include:
Asphyxia Pulmonary hypertension
Pallor (due to anemia)
Edema (hydrops, due to low serum albumin)
Respiratory distress
Coagulopathies (↓ platelets & clotting factors)
Jaundice
Kernicterus (from hyperbilirubinemia)
Hypoglycemia (due to hyperinsulinemnia from islet cell hyperplasia)
Evaluation of immunized patient
The history taking and special examination can help to predict the severity of Rh-incompatibility and hemolytic disease of the fetus.
A detailed evaluation should include:
· Every patient should have her ABO blood group, Rh type, and antibody screen (indirect Coombs test) checked at the first prenatal visit of each pregnancy.
· If the mother is Rh-negative, the blood type of the father must be determined. If both the mother and the father are Rh-negative, there is no need to obtain further antibody screens for Rh-disease. If the Rh-negative mother has an Rh-positive partner the situation should be identified.
· Previous episodes of possible sensitization, such as:
§ - ectopic pregnancy;
§ - spontaneous or elective abortion;
§ - previous blood transfusion with Rh-positive blood;
§ - previous delivery of an Rh-positive infant by an Rh-negative mother.
· Previously affected fetus:
§ - severity of hemolytic disease;
§ - the type of delivery and events surrounding delivery that may increase the risk of Rh-isoimmunization, such as cesarean section, placental abruption, preeclampsia, manual placental removing, external version, amniocentesis, etc.
· knowledge of previous titers.
Maternal antibody screening, which helps in detecting the presence of anti-D antibodies, must be performed in all pregnant women who turn up to be Rh-negative. In this test the maternal serum is incubated with Rh positive erythrocytes and Coomb’s serum (antiglobulin antibodies, aka indirect antiglobulin test). The red cells will agglutinate if Rh antibodies are present in the maternal plasma.
Kleihauer-Betke Test - this is a blood test usually performed in Rh negative mothers, for measuring the amount of fetal hemoglobin transferred from a fetus to mother’s bloodstream as a result of fetomaternal hemorrhage. It is usually performed on Rhesus-negative mothers to determine the required dose of Rho(D) immune globulin (Rh0(D)IgG) to inhibit formation of Rh antibodies in the mother and prevent Rh disease in future Rh-positive children. It is based on the principle that fetal hemoglobin is resistant to acid. In this test maternal blood smear is exposed to an acidic solution (citric acid phosphate buffer). The acid is able to elute adult hemoglobin, but not fetal hemoglobin, from the red blood cells. As a result, on subsequent staining the fetal cells (containing fetal hemoglobin) appear rose-pink in color, while adult red blood cells appear as “ghosts. ” The current recommendation is that every Rh-negative nonimmunized woman who presents to the ED with antepartum bleeding or potential fetomaternal hemorrhage should receive 300 mcg of Rh IgG IM. For every 30 mL of fetal whole blood exposed to maternal circulation, 300 mcg of Rh IgG should be administered. A lower 50-mcg dose preparation of Rh IgG is available and recommended for Rh-negative females who have termination of pregnancy in the first trimester when fetomaternal hemorrhage is believed to be minimal. The dose 300 µg usually used when termination of pregnancy at term 12-19th week gestation. If pregnancy interrupted after 19th week of gestation, the dose should be increased to 500 µg.
Ultrasound examination in the first trimester helps in an accurate estimation of the gestational age. Following that, serial ultrasounds and amniotic fluid analysis help in determining fetal progress. The ultrasound may reveal the evidence of hydrops fetalis and fetal anemia. There could be presence of polyhydramnios and increased placental thickness (greater than 4 cm). The fetus may show pericardial effusion, ascites or pleural effusion and/or echogenic bowel. There could be spenomegaly and hepatomegaly along with the dilatation of cardiac chambers.
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