title: Postoperative decrease in plasma sodium concentration after infusion of hypotonic intravenous solutions in neonatal surgery.
abstract: BACKGROUND
  Hypotonic i.v. solutions can cause hyponatraemia in the context of paediatric surgery. However, this has not been demonstrated in neonatal surgery. The goal of this study was to define the relationship between infused perioperative free water and plasma sodium in neonates.
  
  
  METHODS
  Newborns up to 7 days old undergoing abdominal or thoracic surgery were included in this prospective, observational study. Collected data included type and duration of surgery, calculated i.v. free water intake, and pre- and postoperative plasma sodium. Statistical analyses were performed using the Pearson correlation, Mann-Whitney test, and receiver operating characteristic analysis with a 1000 time bootstrap procedure.
  
  
  RESULTS
  Thirty-four subjects were included. Postoperative hyponatraemia occurred in four subjects (11.9%). The difference between preoperative and postoperative plasma sodium measurements (ΔNaP) correlated with calculated free water intake during surgery (r=0.37, P=0.03), but not with preoperative free water intake. Calculated operative free water intake exceeding 6.5 ml kg(-1) h(-1) was associated with ΔNaP≥4 mM with a sensitivity and specificity [median (95% confidence interval)] of 0.7 (0.9-1) and 0.5 (0.3-0.7), respectively.
  
  
  CONCLUSIONS
  Hypotonic solutions and i.v. free water intake of more than 6.5 ml kg(-1) h(-1) are associated with reductions in postoperative plasma sodium measurements ≥4 mM. In the context of neonatal surgery, close monitoring of plasma sodium is mandatory. Routine use of hypotonic i.v. solutions during neonatal surgery should be questioned as they are likely to reduce plasma sodium.
authors.affiliation: Department of Anaesthesia, Intensive Care and Pain Management.
authors.forename: G
authors.initials: G
authors.lastname: Edjo Nkilly
authors.forename: D
authors.initials: D
authors.lastname: Michelet
authors.forename: J
authors.initials: J
authors.lastname: Hilly
authors.forename: T
authors.initials: T
authors.lastname: Diallo
authors.forename: B
authors.initials: B
authors.lastname: Greff
authors.forename: N
authors.initials: N
authors.lastname: Mangalsuren
authors.forename: E
authors.initials: E
authors.lastname: Lira
authors.forename: I
authors.initials: I
authors.lastname: Bounadja
authors.forename: C
authors.initials: C
authors.lastname: Brasher
authors.forename: A
authors.initials: A
authors.lastname: Bonnard
authors.forename: S
authors.initials: S
authors.lastname: Malbezin
authors.forename: Y
authors.initials: Y
authors.lastname: Nivoche
authors.forename: S
authors.initials: S
authors.lastname: Dahmani
mesh_terms: D000005:Abdomen / Q000601:surgery; D000758:Anesthesia; D019540:Area Under Curve; D003627:Data Interpretation, Statistical; D005260:Female; D006801:Humans; D007010:Hyponatremia / Q000097:blood / Q000209:etiology*; D007038:Hypotonic Solutions / Q000008:administration & dosage / Q000494:pharmacology*; D007231:Infant, Newborn; D007262:Infusions, Intravenous; D007432:Intraoperative Period; D016014:Linear Models; D008297:Male; D011183:Postoperative Complications / Q000097:blood / Q000209:etiology*; D057234:Preoperative Period; D011446:Prospective Studies; D012372:ROC Curve; D012964:Sodium / Q000097:blood*; D013514:Surgical Procedures, Operative; D019616:Thoracic Surgical Procedures
chemical_list: D007038:Hypotonic Solutions; D012964:Sodium
keywords: fluids; hypotonic; i.v.; neonatal surgery; neonates; postoperative hyponatraemia