Methylene Tetrahydrofolate Reductase Deficiency: the Hidden Risk in Paediatric Anaesthesia

takeaway:

• the fed med recommends MDs avoid nitrous oxide with MTHFR patients

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5656162/

Methylene Tetrahydrofolate Reductase Deficiency: the Hidden Risk in Paediatric Anaesthesia

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Because of the common use of N2O, the probability of patients with MTHFR deficiency being exposed to N2O increases. Therefore, it is essential to avoid N2O use in patients with the MTHFR deficiency during anaesthesia management. Moreover, it is noteworthy that N2O may lead to an increase in homocysteine levels in normal patients who do not have an MTHFR deficiency (6). On the other hand, N2O used in anaesthesia for patients with the MTHFR deficiency causes more deleterious effects than in normal patients.   

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Homocysteine levels must be under 7 μmol L−1 for patients with an MTHFR deficiency in the preoperative period to minimise complications. However, one of our patients had a 9.20 μmol L−1 homocysteine value; the peri- and postoperative course was uneventful in that single patient. 

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Conclusion

The common use of N2O should be reviewed because of the existence of undiagnosed patients with an MTHFR deficiency in society.