SECTION II: MANAGEMENT OF DISORDERS AND SPECIAL SITUATIONS
Sickle Cell Disease
Sickle cell disease (SCD) is the most common inherited condition worldwide. Haemoglobin (Hb) transports oxygen from the lungs to the tissues and carbon dioxide back to the lungs for expiration.
Variations of haemoglobin (HbS and HbC), when exposed to low oxygen levels, tend to stick together to form long fibers which may distort the red cell from a round free flowing shape into a sickle shape. These abnormal cells block and sludge the vessels where they are rapidly destroyed, leading to a myriad of complications.
In patients with HbSS, red cell destruction results in haemolytic anaemia and together with occlusion in the small blood vessels, causes most of the clinical features of SCD, including acute painful crises, stroke, pulmonary hypertension, renal dysfunction, retinal disease, leg ulcers, cholelithiasis and avascular bone necrosis.
Women with HbSC experience fewer adverse outcomes, but there is still evidence of an increased incidence of painful crises during pregnancy and fetal growth restriction.
Haemoglobin S, when combined with normal haemoglobin (A), is known as sickle trait (HbAS). It is asymptomatic except for a possible increased risk of urinary tract infections and microscopic haematuria. Although outcomes among women with HbSC are better than in women with HbSS, some do have serious, unpredictable complications, and women with HbSC should therefore be monitored in the same way as those with HbSS.
- Haemoglobin Status of Partner - Women and men with SCD should be encouraged to have the status of their partner tested by haemoglobin electrophoresis before they embark on pregnancy. This information is useful in counseling couples and advising them of the reproductive risks.
- Folic Acid Supplementation - Folic acid (4 mg) should be given once daily both preconceptually and throughout pregnancy.
- Hospital based antenatal care – Care should be hospital based and with facilities for multidisciplinary consultation.
- Screening for end organ damage - Women with SCD should undergo medical review by the haematologist and be screened for end organ damage – e.g. assess renal function, pulmonary hypertension (echocardiography), iron stores with ferretin levels, and the eyes for proliferative retinopathy etc.
- Hydration - Women with SCD should aim to avoid precipitating factors of sickle cell crises such as exposure to extreme temperatures, dehydration, over-exertion, stress and hypoxia. Persistent vomiting can lead to dehydration and precipitation of a sickle cell crisis.
- Early intervention - Women with SCD who become unwell should have sickle cell crisis excluded as a matter of urgency. Pregnant women presenting with acute painful crisis should be rapidly assessed by the multidisciplinary team and appropriate management instituted.
- Caution with iron supplementation – Anemia associated with SCD should not routinely be treated with iron supplementation. Iron supplementation should be given only if there is laboratory evidence of iron deficiency (low ferritin levels)
- Blood pressure and urinalysis - Women with SCD should be evaluated carefully for the onset of pregnancy-induced hypertension. Monitoring for an increase in blood pressure and the presence of proteinuria are essential at each visit. Women with SCD often have a low blood pressure, so an upward trend in blood pressure, even if modest, should be carefully considered.
- Low-dose aspirin - Women with SCD should be considered for low-dose aspirin 75 mg once daily from 12 weeks of gestation in an effort to reduce the risk of developing preeclampsia.
- Midstream urine (MSU) for culture should be performed monthly.
Sonography - risk of fetal growth restriction:
- Routine first-trimester scan (11–14 weeks gestation) to confirm dates and viability.
- Detailed anomaly scan at 20 weeks of gestation.
- In addition, serial fetal biometry scans (growth scans) every 4 weeks from 24 weeks gestation to allow early detection of fetal growth restriction and hence aid appropriate timing of delivery to reduce perinatal mortality and morbidity.
Admission to Hospital and Delivery
- Women with SCD should be advised to give birth in hospitals that are able to manage both the complications of SCD and high-risk pregnancies. SCD should not in itself be considered a contraindication to vaginal delivery.
- Thromboprophylaxis - Should be given to women admitted to hospital. Women with SCD should be advised to receive prophylactic low-molecular-weight heparin during antenatal hospital admissions. The use of graduated compression stockings is also appropriate.
- Fluids and Oxygen - The requirement for fluids and oxygen should be assessed and should be administered if required. Fluids can be given orally and this is the preferred route when strict fluid balance is not ensured.
- Elective Delivery - Women with SCD who have a normally growing fetus should be offered elective birth through induction of labour, or by elective caesarean section if indicated, after 38 weeks’ gestation.
- Pain relief in labour – Women in labour should have the benefit of effective and adequate pain relief. Regional analgesia is recommended for caesarean section.
- IV Access should be maintained and blood cross-matched for delivery.
- Relevant Multidisciplinary Team - senior midwife in charge, senior obstetrician, anaesthetist and haematologist should be informed as soon as labour is confirmed.
- Temperature Regulation and Hydration – Particularly if the room is air-conditioned, the woman should be kept warm and given adequate fluids (by I.V. route if necessary) during labour.
- Intrapartum Fetal Monitoring - Continuous intrapartum electronic fetal heart rate monitoring is recommended owing to the increased risk of fetal distress because of placental insufficiency.
- Early testing for SCD in the infant - where the baby is at high risk of SCD (i.e. the partner is a carrier or affected), early testing for SCD should be performed.
- Maintain maternal oxygen saturation above 94%
- Adequate hydration
- Thromboprophylaxis - Low-molecular-weight heparin should be administered while in hospital and 7 days post-discharge following vaginal delivery or for a period of 6 weeks following caesarean section.
- Care and Vigilance - The same level of care and vigilance should be maintained as has been described for antenatal care, since acute crisis and other complications of SCD remain a risk during the puerperium.
- Discuss contraception especially if the risk of an affected fetus is high, as in the case of the male partner also HbSS or HbSC since in these cases, the risk is 100%. All common options are available, including barrier methods, hormonal methods, the intrauterine contraceptive device and surgical methods (tubal ligation and vasectomy).
Because of the threat which Acquired Immune Deficiency Syndrome (AIDS) poses to the health of women and children, health care workers must be vigilant, so as to identify women and children who may possibly be infected with HIV and implement prevention and/or supportive measures.
Provider initiated testing and conselling (PITC) is practiced in the Caribbean and all pregnant women are offered HIV testing.
Women should be encouraged to disclose their HIV status to their partner and should be given appropriate support. It is also recommended that HIV infected women with existing children of unknown HIV status should have them tested for HIV. The partners of HIV positive women should also be offered HIV testing.
All women testing HIV negative at booking should have access to information about safe sex and high risk scenarios for HIV transmission. Repeat testing should be available at any time during pregnancy. Nurses and doctors managing women during antenatal care should ensure that the HIV result is clearly documented.
While pregnancy is not significantly affected by HIV, there are some adverse pregnancy outcomes that appear to be associated with HIV infection, including:
- Spontaneous miscarriage
- Perinatal mortality
- IUGR (intrauterine growth retardation)
- Low birth weight
- Preterm delivery
Potential routes of vertical transmission from mother to child include:
In utero (high risk period)
- Transplacental passage in utero
- Invasive procedures done during pregnancy
- Infections such as chorioamnionitis
- Ascending infection
- Breaks in the skin of the baby and thus the direct exposure to infected blood
- Ingesting maternal blood
- Breast milk (depends on the presence and duration of breastfeeding and antiretroviral treatment).
All pregnant women who are HIV positive should be referred promptly for assessment and for their pregnancy to be managed by a multidisciplary team including (as a minimum) an HIV physician, obstetrician, specialist midwife, health advisor and paediatrician.
Women who are HIV positive should be screened for genital infections at booking (or after multidisciplinary team referral, if diagnosed HIV positive in pregnancy) and those taking Highly Active Antiretroviral Therapy (HAART) at the time of booking should be screened for gestational diabetes.
Women should also be counseled on condom use during the pregnancy to prevent re-infection and increased viral load.
Persons living with HIV (PLHIV) have higher nutrient requirements than HIV negative individuals. It is important to increase energy intake by 10-100 % based on the physiological need and health status of the individual. Pregnant PLHIV should ingest an additional 6g protein per day as well as a multi-vitamin/mineral supplement daily, in addition to calcium and iron supplements, as needed.
Highly Active Antiretroviral Therapy (HAART)
The WHO (2013) recommendation is that all pregnant HIV-infected women receive a combination triple antiretroviral (ART) drug regimen, regardless of CD4 T count, to prevent perinatal transmission. ART prophylaxis should be started from as early as 14 weeks of gestation or as soon as possible thereafter if women present later in pregnancy, in labour or at delivery.
Women who are HIV positive should be counseled about the increased risk of preterm delivery associated with HAART. Invasive procedures such as fetal blood sampling and fetal scalp electrodes are contraindicated. If labour progress is normal, amniotomy should be avoided unless delivery is imminent. For augmentation of labour, amniotomy and use of oxytocin may be considered. Rupture of membranes should not exceed 4 hours and should be done when the cervix is 6 cms dilated for augmentation of labour. If instrumental delivery is indicated, do lower segment Caesarean section (LSCS). The baby’s nose and mouth should be suctioned at the perineum and the baby washed as soon as possible with soap and water to remove maternal blood and secretions.
Women who are HIV positive were advised to avoid breastfeeding. However, current WHO guidelines enable HIV-infected mothers to exclusively breast feed for 6 months and continue during complementary feeding at least until 12 months with very little risk of HIV transmission. This is the case when antiretroviral treatment is given either to breastfeeding mothers, or as prophylaxis given to infants until 6 weeks after breastfeeding has been discontinued.
WHO (2013) guidelines also recommend that the ART treatment should continue postpartum. Three prophylactic options are offered Option A (through 7 days postpartum), Option B (until one week after cessation of all breastfeeding) and Option B+ (treatment continued for life).
The women should also receive guidance about contraception in the immediate postpartum period. Yearly cervical cytology screening is recommended for all women with HIV, because of the association of HIV, immune-suppression and cervical neoplasia.
Anti-retroviral therapy for the baby should be commenced as soon as possible after birth and certainly within 4 hours. Treatment should continue daily for 4 weeks if the mother had received ART for 4 or more weekes; or for 6 weeks if she recived ART for less than 4 weeks. Infants of mothers on ART who are breastfeeding should receive ART for 6 weeks. These children should be tested at 4-6 weeks and 4-5 months of age. If all these tests are negative and the baby is not being breastfed, the parents can be informed that the child is not HIV-infected.
A confirmatory ELISA test is recommended at 12-18 months of age.