Remember nephrogenic diabetes insipidus in acute surgical patients taking lithium

doi:10.1136/bmj.323.7304.0/d

Remember nephrogenic diabetes insipidus in acute surgical patients taking lithium

Patients taking long term lithium who are admitted as acute surgical emergency cases are at high risk of developing an acuteexacerbation of underlying nephrogenic diabetes insipidus. Intheir lesson of the week, Waise and Fisken (p 96) describe twocases which highlight the importance of being aware that patientswho are taking lithium long term and who present acutely withsurgical problems could have an underlying renal tubular defect.This makes them vulnerable to the effect of preoperative preparationwhen oral intake is withheld. It is therefore crucial to monitorthese patients and calculate any water deficit, which must besupplementedintravenously.