Background The majority of hospital hyponatraemias (serum sodium <135 meq/L) are the outcome of hypotonic fluids infusions in patients with high ADH levels (potently induced by surgery), increasing the risk of cerebral oedema and hyponatraemic encephalopathy.

Purpose To analyse the prescribing practices in perioperative paediatric fluid therapy (POF) in a private clinic.

To elaborate a proposal of intraoperative (IF) and immediate postoperative fluid therapy (PF) (first 24 hours post-surgical), which provides safe standardised recommendations for the paediatric patient (under 18 years).

Material and methods Retrospective observational study. Reviewing a clinic’s own development software, we collected the POF administered to paediatric patients from September 2015 to March 2017. Data were analysed elaborating an Excel database. Then, a bibliographic search was conducted in: MICROMEDEX, UPTODATE and PUBMED using the terms: ‘fluid therapy’, ‘anaesthesia’, ‘perioperative fluid management’, ‘hyponathremy’, ‘hyponatraemic encephalopathy’ AND: ‘newborn’ and ‘paediatrics’. According to recommendations, osmolarity and the contribution of sodium, potassium, chloride and dextrose (D) were evaluated in: D5%, NaCl0. 33%+D5%, NaCl0. 45%+D5% (hypotonics) and NaCl0. 9%, NaCl0. 9%+D5%, lactated Ringer’s (LR) and LR +D5% (isotonics). The volume of fluid was calculated by Holliday–Segar’s formula. An unifying proposal was designed.

Results IF (n=22): LR: 22.7%, NaCl0. 9%: 36.4%, D5%: 9.1%, NaCl0. 9%+D5%: 31.8%.

PF (n=12): 0.9%NaCl: 33.3%, 0.9%NaCl alternating D5%: 41.7%, NaCl 0.9%+D5%: 8.3%. ClK was added in one IF and two PF cases. No formula was used to determine the volume perfused.

Fluids by medical specialty:

• Otorhinolaryngology (n=12): FI: 0.9%NaCl: 41.7%. NaCl0. 9%+D5%: 41.7%. LR: 16.7%. PF (six patients): 0.9%NaCl: 66.7% and 0.9% NaCl+G5%: 33.3%.

• General surgery (n=8): FI: 0.9%NaCl: 25%, G5%: 25%, NaCl0. 9%+D5%: 37.5%, RL: 12.5%. FP (five patients): NaCl0. 9%+D5%: 100%.

• Urology (n=1): IF: NaCl0. 9%+D5%

• Traumatology (n=1): NaCl0. 9%

Recommendations according to current literature (except exceptional clinical conditions):

• Intraoperative: LR.

• PF first 6–12 hours: start tolerance. If it is not possible: LR+D5% or NaCl 0.9%+D5%.

• Add potassium after the first urination or if required.

• If fluid therapy is requered more than 24 hours, monitoring fluids and blood electrolitic status.

• Calculate volume using Holliday–Segar’s formula.

Conclusion

• Despite numerous studies that contraindicate hypotonic fluids in the POF, they are still routinely infused.

• The pharmacy proposal was accepted in daily practice, standardising and avoiding hypotonics POF.

References and/or Acknowledgements E. Bermúdez, clinic’s administrator.

No conflict of interest