Comparison of two maintenance electrolyte solutions in children in the postoperative appendectomy period: a randomized, controlled trial.
OBJECTIVE
To compare two electrolyte maintenance solutions in the postoperative period in children undergoing appendectomy, in relation to the occurrence of hyponatremia and water retention.


METHODS
A randomized clinical study involving 50 pediatric patients undergoing appendectomy, who were randomized to receive 2,000mL/m(2)/day of isotonic (Na 150 mEq/L or 0.9% NaCl) or hypotonic (Na 30 mEq/L NaCl or 0.18%) solution. Electrolytes, glucose, urea, and creatinine were measured at baseline, 24h, and 48h after surgery. Volume infused, diuresis, weight, and water balance were analyzed.


RESULTS
Twenty-four patients had initial hyponatremia; in this group, 13 received hypotonic solution. Seventeen patients remained hyponatremic 48h after surgery, of whom ten had received hypotonic solution. In both groups, sodium levels increased at 24h (137.4±2.2 and 137.0±2.7mmol/L), with no significant difference between them (p=0.593). Sodium levels 48h after surgery were 136.6±2.7 and 136.2±2.3mmol/L in isotonic and hypotonic groups, respectively, with no significant difference. The infused volume and urine output did not differ between groups during the study. The water balance was higher in the period before surgery in patients who received hypotonic solution (p=0.021).


CONCLUSIONS
In the post-appendectomy period, the use of hypotonic solution (30 mEq/L, 0.18%) did not increase the risk of hyponatremia when compared to isotonic saline. The use of isotonic solution (150 mEq/L, 0.9%) did not favor hypernatremia in these patients. Children who received hypotonic solution showed higher cumulative fluid balance in the preoperative period.
Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil; Hospital Universitário de Santa Maria (HUSM), Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, Brazil. Electronic address: mclaravaladao@yahoo.com.br.
Maria Clara da Silva
MC
Valadão
Faculdade de Medicina, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil; Emergency and Pediatric Intensive Medicine Service, Hospital de Clínicas de Porto Alegre (HCPA), Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Jefferson Pedro
JP
Piva
Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil; Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil; Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil.
João Carlos Batista
JC
Santana
Universidade de São Paulo (USP), São Paulo, SP, Brazil; Pediatric Service, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, RS, Brazil.
Pedro Celiny Ramos
PC
Garcia
D000293:Adolescent; D001062:Appendectomy / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D004231:Diuresis / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D005947:Glucose / Q000008:administration & dosage; D006801:Humans; D007010:Hyponatremia / Q000097:blood / Q000517:prevention & control*; D007038:Hypotonic Solutions / Q000008:administration & dosage; D007223:Infant; D007262:Infusions, Intravenous; D007552:Isotonic Solutions / Q000008:administration & dosage; D008297:Male; D011183:Postoperative Complications / Q000517:prevention & control*; D011184:Postoperative Period; D011189:Potassium Chloride / Q000008:administration & dosage; D057234:Preoperative Period; D011446:Prospective Studies; D012964:Sodium / Q000097:blood; D012965:Sodium Chloride / Q000008:administration & dosage
D007038:Hypotonic Solutions; D007552:Isotonic Solutions; D012965:Sodium Chloride; D011189:Potassium Chloride; D012964:Sodium; D005947:Glucose
Fluid therapy; Hidratação; Hipernatremia; Hiponatremia; Hypernatremia; Hyponatremia; Hypotonic solutions; Isotonic solutions; Postoperative period; Pós-operatório; Soluções hipotônicas; Soluções isotônicas