Ketamine anaesthesia in a child with phenylketonuria: a case report and brief review

There is no clarity regarding the anaesthetic management of patients with phenylketonuria (PKU). The mechanism of permanent intellectual disability in PKU is still not understood. The association of phenylalanine with N-methyl-D-aspartate (NMDA) receptor inhibition is among the proposed mechanisms to explain the pathophysiology. Data on the use of ketamine, an NMDA receptor antagonist, in PKU patients are insufficient. Therefore, we present our experience with short-acting anesthesia using ketamine in a 7-year-old patient with PKU in whom no neurocognitive or systemic adverse effects were observed during the postoperative follow-up period. No significant systemic or overt behavioral side effects were reported. This single observation cannot prove cognitive safety or mechanistic compatibility. Further controlled studies involving pre- and post-operative biochemical and objective neurocognitive assessments are needed.