On balance and not knowing: the example of obstetric cholestasis

small_589169284There is a real need for balance in maternity care.  Very occasionally, things can go horribly wrong, which means that vigilance is a vital midwifery skill and we can be very grateful for the array of tools, tests, interventions and pharmaceuticals that are occasionally life-saving.  But on the other side of the seesaw, the vast majority of births will – especially if allowed to unfold physiologically and without undue interference of all the kinds described in the last sentence – progress well to a happy, healthy conclusion for all concerned.  If we apply too little vigilance and/or eschew intervention where it is truly warranted, we may end up with high rates of unecessary intervention, iatrogenic morbidity, unhappy mums, unsettled babies and all manner of unwanted and perhaps sometimes unknown knock-on effects, which can be emotional and social as well as physical.

The concept of balance can also be considered in relation to the knowledge that we use to underpin decision-making and practice, and the enormous difficulty with achieving the balance described above is that this is not an exact science.  It’s not really, of course, a science at all.  It’s an art which involves juggling different kinds of partial knowledge and bits of information which are often taken out of context and then trying to work out how to deal with the huge gaps of what we don’t know.  Some of this knowledge might come from research and then some will come from other sources, such as expert opinion.  Both, and every other kind of knowledge we generate or use, have advantages and disadvantages.

A good example of a situation which requires balance in both of the dimensions described above is that of obstetric cholestasis, also known as intrahepatic cholestasis of pregnancy (ICP), and I have recently uploaded a couple of related articles which explore this a bit further.  As the RCOG Green Top Guideline on this shows, there is very little research evidence available to underpin recommendations, and so, as I discussed in my ReView of the obstetric cholestasis guideline, there is a significant reliance on expert opinion as a form of knowledge.  In Exploring Expert Opinion, I have pondered just a few of the issues raised by this.  I absolutely acknowledge the concerns that exist about this condition, yet I also see an increasing tendency to intervene in the pregnancies of women who may be affected by this without perhaps having as much knowledge as might be ideal.  This intervention, as I noted near the beginning of this post, can increase the likelihood of other problems, which then necessitates consideration of which way the seesaw is moving.

crafty_penguinI have spent years researching and writing about areas in which practice recommendations have become almost cemented in place without us really having done enough research to know if they are the right recommendations, or to know whether other possibilities exist.  It only takes a few years after such foundations are cemented before the idea of carrying out additional research (which, in the case of the kind of trial that is deemed necessary in some circles to provide adequate evidence, necessitates removing the now-accepted intervention from those in the control group) is deemed unethical.  I see, in this example, potential danger in applying the results of the recent study into obstetric cholestasis by Geenes et al (2013) without some ongoing clear thinking.  This prospective population-based case-control study published earlier this year found that,

“Women with severe ICP and a singleton pregnancy (n=669) had increased risks of preterm delivery (164/664; 25% vs. 144/2200; 6.5%; adjusted OR 5.39, 95% CI 4.17 to 6.98), neonatal unit admission (80/654; 12% vs. 123/2192; 5.6%; adjusted OR 2.68, 95% CI 1.97 to 3.65) and stillbirth (10/664; 1.5% vs. 11/2205; 0.5%; adjusted OR 2.58, 95% CI 1.03 to 6.49) compared to controls. Seven of 10 stillbirths in ICP cases were associated with co-existing pregnancy complications.” (Geenes et al 2013).

surgeon_penguinThis may well reflect the fact that obstetric cholestasis is a serious condition which leads directly to poor outcomes and thus needs to be the focus of our attention.  The finding that severe ICP leads to greater neonatal unit admission is arguably not as useful as the knowledge that it is more likely asssociated with stillbirth, because neonatal unit admission is a human-generated outcome that occurs because someone makes a decision.  Of course there will be many cases where any professional who met the baby in question would make the same decision, but not all cases are clear cut.  It may be that one or more babies appeared to be within normal limits physically but their paediatrician had foreknowledge that their mothers had ICP and thus felt (quite justifiably; please understand that I am not critisicing my imaginary paediatrician) that it would not hurt to spend a few hours being more thoroughly checked in the neonatal care unit.

The finding that stillbirth was more common in babies born to mothers with ICP is more significant.  But it is important to consider the related finding that, in 7 out of 10 instances, there were co-existing pregnancy complications.  We clearly have much more to learn about this situation and it may be better that we try and learn more before we start applying widespread monitoring and/or intervention that may not be helpful and that may impede our ability to learn in the future.  In the meantime, we may need to take care to remember to be honest with women about the extent of our knowledge which, as the articles above demonstrate, isn’t yet all that great.

So often, I end up thinking that this all comes down to humility.  Within a society that puts a high value on expertise, it is very difficult for professionals in any field to admit that they don’t know something, and yet, if we were all truthful, ‘we don’t know’ would be the most commonly uttered phrase in maternity care encounters.

 

Geenes V, Chappell LC, Seed PT et al (2013). Association of severe intrahepatic cholestasis of pregnancy with adverse pregnancy outcomes: A prospective population-based case-control study. Hepatology, 15 July 2013. Online ahead of print.

 

photo credit: rachaelvoorhees  via photopin cc