In pregnancy, steroids are used for the same inflammatory conditions as in the nonpregnant state, such as sarcoidosis and rheumatoid arthritis. They may also be used for obstetric medical conditions, for example recurrent miscarriages or antiphospholipid syndrome. Finally, maternal administration of glucocorticoids (usually dexamethasone or betamethasone) has been shown to reduce the incidence of respiratory distress syndrome and related complications in premature babies; the drugs are usually given as two doses 12-24 hours apart. The benefit is greatest at 30-32 weeks’ gestation and when delivery occurs within 1-7 days after the administration of steroids.
Problems and special considerations
Anaesthetic concerns are related to the underlying reason for steroid therapy, the presence of side effects of steroids and the requirement for supplementary steroids to cover the stress of delivery.
Side effects
These are well known and no different in the pregnant state to those in the non-pregnant state, and they may be of relevance to the anaesthetist (e.g. electrolyte disturbance, osteoporosis). In general, hydrocortisone and prednisolone are about 90% metabolised by the placenta and therefore little reaches the fetus. However, maternal dosage above 10 mg prednisolone per day has been associated with neonatal adrenal suppression, and similar effects are theoretically possible in breastfed neonates, although reported measured concentrations of steroids in breast milk have been extremely low. There are unlikely to be adverse maternal effects of short-term administration of steroids given for premature delivery, although a raised white cell count is common and this may potentially complicate the diagnosis if infection is suspected. Transient reductions in fetal heart rate variability have been reported.
Steroid supplementation
Severe hypotension characterises the acute adrenocortical insufficiency of Addison’s disease, and hypotension may also occur following surgery or trauma in chronic takers of steroids who do not receive supplementation, presumably as a result of suppression of the adrenals’ ability to mount a stress response. This has led to the recommendation that all patients on steroid therapy should receive supplementation perioperatively. However, the population at risk is uncertain, although most authorities would include all those with more than a week’s steroid therapy within the last 3-6 months. If too much supplementary steroid is given, there is at least a theoretical risk of increased susceptibility to infection; in addition, many patients dislike taking increased doses because depression and other mood changes may be apparent even after a short time, although other side effects typically take longer to occur. Finally, the amount of steroid reaching the neonate through breast milk, even though it is small, should be kept to a minimum.
Management options
In general, the management plan for these women should be made in collaboration with an endocrinologist, and adapted according to the particular circumstances of the case.
For general surgery, a more logical approach than the traditional ‘200 mg hydrocortisone 6-hourly’ is to consider the normal endogenous response to surgery and to ensure that the equivalent amount of steroid is provided: for example, 25-50 mg hydrocortisone for minor surgery, 75-100 mg for intermediate surgery and 100-150 mg for major surgery (note that 1 mg prednisolone is equivalent to 4 mg hydrocortisone). This daily amount is required for 1-3 days depending on the extent of surgery and should include any therapy the patient is already taking, such as a maintenance dose.
Labour and delivery (including caesarean section) should generally be considered major surgical stress, although the stress of a prolonged and difficult labour is likely to be greater than that of a simple and rapid one. If the patient is already taking adequate steroid to cover the daily requirement, no extra steroid should be required so long as the usual dose can be taken orally. If supplementation is necessary, it can be given as intravenous hydrocortisone or oral prednisolone, each tapered after the required period. It is recommended that parturients with Addison’s disease be commenced on hydrocortisone at the start of active labour or before a planned caesarean section, at a dose of 50-100 mg 6-8-hourly or on a continuous infusion of 200-300 mg per 24 hours, until delivery. This dose should be doubled post-delivery then tailed off to the pre-pregnancy dose after 24-48 hours, as clinically appropriate.
Key points
• Steroids may be given for medical or obstetric purposes.
• Side effects may be important to the anaesthetist just as in the general population, although they are usually not a problem after administration for premature delivery.
• Steroid cover should be given according to the particular circumstances of the case, but most patients require less than is traditionally given.
Further reading
Kemp MW, Newnham JP, Challis JG, Jobe AH, Stock SJ. The clinical use of corticosteroids in pregnancy. Hum Reprod Update 2016; 22: 240-59.
Lebbe M, Arlt W. What is the best diagnostic and therapeutic management strategy for an Addison patient during pregnancy? Clin Endocrinol 2013; 78: 497-502.
McDonald SD. Antenatal corticosteroids for women at risk of preterm delivery. BMJ 2017; 356: j1467.