Children with diabetes insipidus associated with the lack of thirst (adipsia) may experience severe oscillations in their serum sodium levels requiring frequent and prolonged hospitalizations. On one hand, they are at risk of hyponatraemia resulting from excessive fluid intake due to absolute or relative overdosage of desmopressin. On the other hand, due to the absence of thirst, they are also at risk of hypernatraemia due to fluid deprivation if lost fluids are not properly replenished.1,2

We present the cases of 3 children with panhypopituitarism with antidiuretic hormone deficiency (central diabetes insipidus) and adipsia as immediate complications of surgical removal of large hypothalamic tumours. After a protracted postoperative hospital stay due to countless episodes of hyponatraemia and hypernatraemia, patients could be discharged home and managed at the outpatient level by providing parents with a portable system for measuring capillary blood sodium levels at home.

The patients were 2 girls and 1 boy aged 5.5, 15 and 9 years, respectively, that had undergone surgery for treatment of craniopharyngioma, optic nerve glioma and mixed germ cell tumour and were hospitalised for 96, 105 and 53 days (42, 9 and 23 of these days in the intensive care unit). The complications from abnormal sodium levels in these patients included status epilepticus and cerebral oedema secondary to hyponatraemia in the 2 younger patients and thromboembolic disease secondary to hypernatraemia in the adolescent patient.

We provided parents with a portable blood analysis device (EPOC point-of-care blood analysis system; Epocal Inc, Ottawa, Canada) that has been validated for measurement of capillary blood sodium concentrations on account of the good correlation of these measurements with those obtained by benchtop methods.3 The system requires 92μL of capillary blood per test and provides results in 3.5min, with an approximate cost of 5 euro per measurement. The device is portable, as it weighs only 680g, and can perform 50 measurements on one battery charge. We held a training session for parents and primary care providers (paediatricians and nurses) on the use of this system, and during the hospital stay we trained parents on how to collect capillary blood samples, on the management protocol and how to respond to abnormal sodium levels. Table 1 presents the contents of the printout of recommendations given at discharge. Families were informed that they could contact the clinic by telephone between 13:30 and 15:00 pm on weekdays.

The 3 families assumed the responsibility to monitor serum sodium levels at home, which they preferred over visiting a health care centre or laboratory. The patients have returned to school and leisure activities, and parents have returned to work. At the time of this writing, the duration of at-home follow-up in the 3 patients has been of 20, 10 and 7 months, with a follow-up visit at our clinic every 3 months. In this interval, they have needed to visit the emergency department 6 times for reasons related to their sodium levels (Table 2), leading to short hospitalizations (<48h), except in one case in which hypernatraemia triggered acute kidney injury, which prolonged the hospital stay to 14 days.

Home monitoring of capillary blood sodium levels is a rare practice, with barely half a dozen of children using this approach reported in the current international literature, but this measure is completely accepted by its users.4–6 With its implementation, we are taking another step to increase patient safety, family quality of life and, ultimately, to make paediatrics practice more humane. The use of home serum sodium monitoring could facilitate patient discharge, reduce the frequency of readmissions and the associated lengths of stay, reduce the number of visits to health care centres, allow an earlier return to school, work and leisure activities and open more time for children to enjoy their childhoods. A structured educational programme is essential in this approach to facilitate adherence to treatment by the family and good communication between health professionals (nurse-paediatrician) and between levels of care (primary care-hospital-based care).