Pregnant women admitted with respiratory complications should be managed jointly between the obstetric and medical teams. An assessment needs to be made with respect to the best place to manage the woman. There should be early involvement of obstetric anaesthetists, respiratory physicians and haematologists and a clear management plan needs to be set out from the outset.
Women requiring more respiratory support may be best managed in the Respiratory Unit with close input by the obstetric and midwifery teams. If a woman is in labour, she would be best managed in the Delivery Unit with input from the Respiratory team and the Obstetric Anaesthetic team. Following delivery, she may need to be transferred to the clinical area that would be best to provide expert care for her.
It is important to bear in mind that pregnancy related pathologies such as chorioamnionitis, severe urinary tract infections, group A and B streptococcus infections and even malaria may present with similar symptoms. Careful clinical assessment is of vital importance in order not to miss an important infection. The patient needs to be carefully monitored with the modified early warning scores, taking into account the pregnancy. Complications of obstetric problems such as pre-eclampsia, venous thromboembolism and pulmonary embolism have also to be excluded.
The most common complication of A H1N1 influenza is pneumonia. The plan of management in such cases has been summarized in Table .
Clinical management of women admitted with pneumonia secondary to H1N1 infection
Complications must be recognized and treated appropriately. In order to treat pneumonia effectively, the antimicrobial therapy should be based on bacteriological sensitivities. However, pending bacteriological confirmation, co-amoxiclav (Augmentin) is the recommended empiric antibiotic. In penicillin sensitive patients, Clarithromycin is a suggested alternative. Co-amoxiclav is not contraindicated in pregnancy. In situations where there is preterm prelabour rupture of membranes concomitant with pneumonia, the use of co-amoxiclav is not recommended because of the increased risk of necrotizing enterocolitis observed in the ORACLE study. An alternative antibiotic such as piperacillin is recommended and the microbiologist should be involved in management discussions. In addition, antiviral treatment should be started on clinical grounds whilst awaiting test results. It is also important to treat maternal pyrexia with paracetamol and not Non Steroidal Anti Inflammatory Drugs (NSAID). Epidemiological studies have linked uncontrolled maternal pyrexia to miscarriage and fetal abnormalities such as neural tube and cardiac defects. Maternal pyrexia is also a recognised risk factor for preterm delivery. The importance of control of maternal pyrexia with regular and effective doses of paracetamol and hydration should be emphasised.
Current obstetric practice is to administer corticosteroids e.g. 2 doses of betamethasone or dexamethasone 12 or 24 h apart to promote fetal lung maturity in situations of threatened pre-term labour or where a decision is made to deliver the fetus prematurely for maternal or fetal reasons. The effects on the maternal immune system from a single course of corticosteroids are unclear but the evidence does not suggest that it results in sufficient immuno-suppression to cause maternal harm or exacerbation of infection.
The administration of corticosteroids is important for the promotion of fetal lung maturity, and the benefits outweigh the risks. Recent evidence suggests that repeated (rescue) doses of corticosteroids may be beneficial for fetal reasons, but studies have also shown that these may lead to maternal secondary adrenal insufficiency and fetal complications. The practice of repeated (rescue) doses of corticosteroids is not recommended.
The use of high dose steroids for the treatment of pulmonary complications is not recommended by ICU specialists for fear of immune suppression and prolonged viral shedding.
Decision for Delivery
Most mothers with symptoms of influenza in labour will be able to tolerate labour with adequate pain relief and hydration. In most cases, the decision to deliver will be made for an obstetric indication. In the event of a critically ill woman close to term, it is not unusual to deliver her baby, usually by caesarean section, to help with mechanical ventilation of the lungs to improve her recovery. This should be done once her clinical condition is stabilised and other potential complications such as coagulopathy have been excluded or corrected.
As indicated above, most of the respiratory complications have been shown to occur in the second and third trimesters. There may be situations where a preterm baby needs to be delivered in order to improve the outcome for ventilation of a very ill mother. The decision is made in conjunction with the obstetric, critical care and neonatal teams. The pregnant woman should be informed but if unable to participate in clinical decision making, the partner or close relatives should usually be involved in discussions. In order to improve the outcome for the premature infant, corticosteroids (in accordance with the guidance above) should ideally be administered at least 24 h prior to delivery. It is unlikely that pregnancies in the 1st or early second trimesters will need to be terminated unless it is felt that continuation of the pregnancy will be detrimental to the woman’s condition. There may be occasions where a woman who is booked for elective caesarean section becomes symptomatic at the time of the planned procedure. If possible, it would be advisable to commence her on antivirals and to delay the procedure by about 5 days, to allow her to recover, in order not to increase her risks of respiratory complications, and also to reduce the risk of spread to other patients and staff. In severe cases of respiratory complications where the woman has developed Adult Respiratory Distress Syndrome (ARDS) and where she is not responding to mechanical ventilation, she may have to be considered for Extra Corporeal Membrane Oxygenation (ECMO). This is highly specialized treatment and the decision is made by the Intensive Care specialists. As above, it may not always be necessary to terminate a pregnancy in the first or early second trimesters as there is no benefit in doing so for maternal ventilation. It is of vital importance to maintain the maternal physiology in the best possible state in order to allow the satisfactory progress of the pregnancy. There is now more capacity for ECMO treatment in the UK and more pregnant women are being referred to ECMO units for treatment. It is vitally important that the obstetric teams in the ECMO units are jointly involved in the mother’s care and good communication is essential.
Post Natal Period
Women in the postnatal period are probably at lower risk of respiratory complications because the effects of the gravid uterus on the lungs have been removed. However, they may still experience similar complications if they are infected and there is a risk of transmission to the newborn infant. They should observe the same strict hygiene measures and be offered antiviral medication i.e. oseltamivir if clinically indicated. Mothers should be encouraged to breastfeed. Breast feeding is important and should be continued as long as possible.
The benefits of breastfeeding are significant and are two-fold: (i) it gives babies the most appropriate nutrition for health and promotes attachment between mother and baby and (ii) colostrum is rich in antibodies which will help to protect the baby from many infections. Women who are breastfeeding and have symptoms of influenza should be treated with an antiviral medicine. The preferred medicine is oseltamivir, as for other adults. However, if a baby is born and breastfeeding is started while the woman is taking zanamivir, she should complete the course of zanamivir; it is not necessary to switch to oseltamivir.
If the woman is too tired to breastfeed, she should be encouraged to express her breast milk in order to feed her baby. She should get help with breastfeeding and her baby should be with her as much as possible. She should observe strict hygiene measures to avoid spread of the virus to her baby.