Predictors of perioperative complications in paediatric cranial vault reconstruction surgery: a multicentre observational study from the Pediatric Craniofacial Collaborative Group

Cranial vault reconstruction is performed in children with craniosynostosis in order to increase the cranial volume and thus prevent complications associated with raised intracranial pressure.   Procedures are normally performed in infancy, the period of rapid brain growth.  Different centres perform different operations in patients of different ages, making comparison of risk and benefit of different approaches challenging.

In this paper, the latest in a series of papers arising from this database, Goobie and colleagues performed a univariate analysis to identify variables associated with major complications in children undergoing cranial vault surgery.  Complex cranial vault reconstruction was defined as fronto- orbital advancement (FOA), middle/posterior cranial vault reconstruction, or total cranial vault reconstruction (CVR). The procedures identified as neuro-endoscopic procedures, spring-mediated cranioplasties and modified Pi procedures were excluded.   The authors report that preoperative predictors of complications included ASA physical status 3 or 4, patient with a craniofacial syndrome, antifibrinolytic not administered, blood product transfusion >50 ml kg, and surgery duration over 5 h.

Take Home Message / Commentary

This is a great paper if you love statistics.  Susan Goobie is a first class researcher and a brilliantly clear thinker, so I feel confident that the analysis has been performed as well as can be.  In particular, there is now such a strong argument for antifibrinolytic use that it could be considered routine best practice, with the burden moving from advocates needing to justify its use to non-advocates justifying their non-use.

For the humble worker bee, however, there aren’t that many other take home points from such a large body of work, demonstrating the limitations of pooling data.  Particularly disappointing was that the paper did not reveal what the complications actually were (they were in an appendix that was not attached to the pdf copy of the paper) and that complications were not broken down by operation.

In particular:

  • FOA and CVR are quite different operations, and I’m not convinced that pooling their results is all that useful. In the Australian cranioplasty audit of 2008 that many SPANZA members contributed to (1), the median blood loss for these operations was quite different, but the incidence of unexpected major haemorrhage was similar.
  • Duration > 5 hours’ and ‘intraoperative transfusion >50ml/kg’ were also associated with a higher risk of complications – but without the information about different operations, this might be another way of demonstrating that some operations take longer and involve more bleeding than others.
  • Knowing details of the complications would help us to learn from the data presented. Knowing the median duration and blood loss data for a particular operation might help me evaluate what happens in my home hospital.  Furthermore, I would be interested to know if a certain operations or therapy was associated with an increased risk of seizures, but less interested if an operation that is known to involve a large blood loss is associated with an increased risk of large blood loss.

The authors claim that they have presented a clinically relevant tool to predict which craniosynostosis patients are at risk of a major post-operative event.  Other than the point about antifibrinolytics, I am not convinced that their paper supports this claim.  The authors admit as much in their sensible and well written conclusion:

“Whilst neither age nor patient weight was predictive of major complications in our cohort, published reports show that age <9 months or weight <10 kg is related to increased perioperative complications in these children…. Therefore, expert consensus would recommend that the age at time of CCVR should be considered when feasible with elective operations planned for >10 kg and age >9 months when possible and safe.’

  1. Howe PW, Cooper MG. Blood loss and replacement for paediatric cranioplasty in Australia–a prospective national audit.  Anaesthesia and intensive care, 2012

Reviewed by: Dr Peter Howe